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EXISTENCE,UNIQUENESS AND MULTIPLICITY OF ROTATING FLUXON W A VES IN ANNULAR JOSEPHSON JUNCTIONS GUY KATRIEL Abstract.We prove that the equation modelling an annular Joseph-son junction has a rotating ?uxon wave solution for all values of the parameters.We also obtain results on uniqueness of the rotating ?uxon wave in some parameter regimes,and on multiplicity of rotating ?uxon waves in other parameter regimes.1.Introduction The equation modelling a long Josephson junction is [7](1)φtt +αφt +sin(φ)=φxx +βφxxt +γ,where α>0,β>0,γ>0(α,βdescribe dissipative e?ects,while γdescribes the applied bias current).In the case of annular geometry the periodicity condition (2)φ(x +L,t )=φ(x,t )+2π,is imposed,where L is the circumference of the junction.De?nition 1.A rotating ?uxon wave is a solution of (1),(2)of the form (3)φ(x,t )=θ(kx +ωt ),where the function θ(z )satis?es (4)θ(z +2π)=θ(z )+2π?z ∈R .Clearly the assumption that (3)satis?es (2)implies that (5)k =2π
ω.
2GUY KATRIEL
Substituting(3)into(1)we obtain
(6)βωk2θ′′′(z)+(k2?ω2)θ′′(z)?αωθ′(z)?sin(θ(z))+γ=0,
so that rotating?uxon waves are given by solutions(ω,θ(z))of(6),withθ(z) satisfying(4).
Our aim in this paper is to study the questions of existence and unique-ness/multiplicity of rotating?uxon waves.We shall obtain existence of a ro-tating?uxon wave for all values of the parameters:
Theorem2.For any L>0,α>0,β>0,γ>0,(1),(2)has a rotating ?uxon wave solution(3),withω>0.
To prove Theorem2and our other results,we use methods of nonlinear functional analysis,reducing the problem to a?xed-point equation depending on a parameter(ω),to be solved by means of Leray-Schauder theory,coupled with an auxilliary scalar-valued equation,which we analyze.We have used a similar technique to prove existence of travelling waves of the discrete damped and dc-driven sine-Gordon equation[5].The details of the analysis di?er,and in the discrete sine-Gordon case we could not prove existence for all parameter values(which re?ects the phenomenon of‘pinning’in the discrete case)-while here we are able to do so.
Several researchers have studied long Josephson junctions,and annular ones in particular,experimentally,[2,8,9],numerically[1,6]and analytically [3,4,6,7].
Note that in the caseβ=0(known as the damped dc-driven sine-Gordon equation),(6)reduces to the damped dc-driven pendulum equation which is amenable to phase-plane analysis and is thus well understood,and the existence of rotating?uxon waves for allα>0,γ>0is known(see[10], Section2.2).The situation forβ>0is di?erent.Most existing analytical studies assume that eitherα,βandγare small,so that the equation is treated as a(singular)perturbation of the sine-Gordon equation(the case α=0,β=0,γ=0of(1)),or thatβis small so that the equation is a perturbation of the damped dc-driven sine-Gordon equation.An exception is [6],which studies travelling?uxon waves of kink type on an in?nite line,that is,solutions of(1)of the form(3)with(4)replaced byθ(+∞)?θ(?∞)=2π. Existence results for such waves are proved by a geometric analysis of the corresponding three-dimensional phase-space,and a very intricate structure of solutions is revealed.Here,as we noted,our approach is functional-analytic rather than geometric,leading to the general existence result of Theorem2.
Our method also allows us to derive some further information about the set of rotating?uxon waves.In the physical literature,a common and useful way to describe the behavior of a system is the‘I-V characteristic’-in this case theγ?ω(bias current-frequency)characteristic:
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS3 De?nition3.The bias-frequency characterstic is the setχ?(0,∞)×(0,∞) of all pairs(ω,γ)for which(1),(2)has a rotating?uxon wave(3),with fre-quencyω.
The setχdepends,of course,on the parameters L,α,β.The following theorem shows that the setχis‘large’.
Theorem4.For any L>0,α>0,β>0,the bias-frequency characteristic χhas a subsetχ0?χwhich has the following properties:
(i)χ0is connected.
(ii)For anyω>0there existsγ>0with(ω,γ)∈χ0.
(iii)For anyγ>0there existsω>0with(ω,γ)∈χ0.
(iv)(0,0)∈
α≤ω≤γ
L
>1
and
(9)α+βk2≥√
γ(ω))|ω>0}
4GUY KATRIEL
where
γ(0)=0,
(12)lim
ω→+∞
γ(ω)=γ.
Let us note that in the caseβ=0,part of the above theorem is not true:whileχis connected and can be parameterized as in(10)(for any k>0,α>0;see[10],sec.2.2),the function
2.
Then there exists a valueγ0>0such that given any0
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS 5
An important issue which we do not address here is the question of stability.For example:is it true that for any value of α>0
,β>0,γ>0there exists at least one rotating ?uxon wave of (1)which is at least locally asymptotically stable?
2.Existence of rotating fluxon waves
In this section we prove Theorem 4,which in particular implies Theorem
2.To do so we ?rst recast our problem into a functional-analytic form,so that we can apply Leray-Schauder theory.
Multiplying both sides of (6)by θ′(z )and integrating over [0,2π],taking
(4)into account,we obtain
ω βk 2 2π0(θ′′(z ))2dz +α
2π0
(θ′(z ))2dz =2πγ.By our assumption that α>0,β>0,γ>0this implies that ω>0,as stated in Proposition 5,and thus we may set
(15)λ=1
λ
u ′′(z )?αu ′(z )?λsin(z +u (z ))+λγ?α=0.
Rotating ?uxon solutions of (1),(2)thus correspond to pairs (λ,u (z ))with λ>0and u (z )satisfying (17),(18).
By integrating (18)over [0,2π],taking (17)into account,we obtain
(19)1
λ,so that we can rewrite (18)as
βk 2u ′′′(z )+ λk 2?
12π 2π0
sin(s +u (s ))ds =0.
(20)We note that if (λ,u (z ))is a solution to our problem then so is (λ,u (z +c )+c )for any constant c (this of course corresponds to the time-invariance of (1)),
6GUY KATRIEL
hence by adjusting c we may assume that
(21) 2π0u(s)ds=0.
We thus seek pairs(λ,u(z)),satisfying(17),(19),(20)and(21).
Multiplying(20)by1+u′(z)and integrating over[0,2π]we obtain Lemma9.Any solution(λ,u)of(17),(20)and(21)satis?es (22)λ 2π0sin(s+u(s))ds=βk2 2π0(u′′(s))2ds+α 2π0(u′(s))2ds.
In particular,together with(19),(22)implies that
λγ≥α,
which gives the upper bound of(7).Also,noting that the value of the integral on the left-hand side of(19)is at most1,we have
(23)γ?1≤
α
2π 2π0(u′′′(s))2ds 1
2π 2π0(u′(s))2ds 1
2π 2π0(u(s))2ds
1
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS7 We de?ne a family of linear mappings Lλ:X→Z(λ=0)by (25)Lλ(u)=βk2u′′′(z)+ λk2?1
2π 2π0sin(s+u(s))ds.
Solving(17),(20),(21)is equivalent to solving
(27)Lλ(u)=λN(u),u∈X,
so that our problem reduces to:?nd(λ,u)∈(0,∞)×X such that(27)and (19)hold(we note that,by a simple bootstrap argument,any solution u∈X of(27)is in fact C∞).In other words,de?ning the nonlinear functionalΦ: (0,∞)×Z→R by
(28)Φ(λ,u)=α
2π 2π0sin(s+u(s))ds,
we need to solve the pair of equations(27)and
(29)Φ(λ,u)=γ,
for the unknowns(λ,u)∈(0,∞)×X.
We derive some estimates on Lλwhich will be useful.Let u∈X and write u as a Fourier series
u(z)= l=0a l e ilz.
Noting that
Lλ(e ilz)=? (lα+βk2l3)i+l2(λk2?λ?1) e ilz,
so that
L?1
λ
(e ilz)=? (lα+βk2l3)i+l2(λk2?λ?1) ?1e ilz,
8GUY KATRIEL
we obtain
L?1λ(u) Y= l=0a l (lα+βk2l3)i+l2(λk2?λ?1) ?1e ilz Y
= l=0l2|a l|2 (lα+βk2l3)2+l4(λk2?λ?1)2 ?1 1
2
≤ (α+βk2)2+(λk2?λ?1)2 ?12
= (α+βk2)2+(λk2?λ?1)2 ?1
2
.
In particular(dropping the?rst term on the right-hand side of(30))
(31) L?1
λ Z,Y≤
λ
2
≤λ2=λ
|λ2k2?1|.
De?ning F:(0,∞)×Z→Z by
(33)F(λ,u)=λL?1
λ?N(u),
we may rewrite(27)as
(34)u=F(λ,u),u∈Z.
We note that since L?1
λmaps Z onto X,any solution u∈Z of(34)is in fact
in X.
Since sin(z+u(z)) L2≤1and N(u)is the orthogonal projection of sin(z+u(z))∈L2[0,2π]into Z,we have
(35) N(u) Z≤1?u∈Z.
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS9 Using(35)and(30),we have the bound:
(36)
F(λ,u) Z≤ F(λ,u) Y≤λ (α+βk2)2+(λk2?λ?1)2 ?1
Σ0.
Since the mapping F that we have de?ned satis?es the hypotheses of Theorem10,we have a setΣ0as in the Theorem.
We de?neχ0?χby
(39)χ0={(ω,Φ(ω?1,u))|ω>0,(ω?1,u)∈Σ0},
and we will show thatχ0has all the properties claimed in Theorem4.
SinceΦis continuous andΣ0is connected,χ0is connected,so we have (i)of Theorem4.
Part(ii)of Theorem4follows from the following
Lemma11.LetΣ0be as in Theorem10.For anyλ>0there exists u∈Z such that(λ,u)∈Σ0.
10GUY KATRIEL
proof:Since from(34)and(36)we have
(40)(λ,u)∈Σ? u Z≤λ1
Σ0,Λalso contains arbitrary small positive values.SinceΣ0,henceΛ,is connected,we conclude thatΛ=(0,∞).
To prove thatχ0satis?es property(iii)of Theorem4(and hence also Theorem2),we need to show that
(41)(0,∞)?Φ(Σ0).
SinceΣ0is connected andΦis continuous,Φ(Σ0)is also connected,so that to prove(41)it su?ces to show thatΦtakes arbitrarily large and arbitrarily small positive values onΣ0.Since the integral in the de?nition(28)ofΦis bounded by1,it is immediate that
(42)lim
λ→0+,(λ,u)∈Σ
Φ(λ,u)=+∞,
so thatΦtakes arbitrarily large values onΣ0.We shall prove
Lemma12.
(43)lim
λ→+∞,(λ,u)∈Σ
Φ(λ,u)=0.
This implies thatΦtakes arbitrarily small positive values onΣ0,com-pleting the proof of(41),and thus of part(iii)of Theorem4holds.
proof of Lemma12:Applying Wirtinger’s inequality(24)with v=u′, Lemma9implies
(44)
(λ,u)∈Σ?λ1
2π 2π0(u′(s))2ds.
From(34)and(31)we obtain
(45)(λ,u)∈Σ? u Y≤λ2
2π 2π0sin(s+u(s))ds
≤(βk2+α)λ3
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS11 which implies that
(46)lim
λ→+∞,(λ,u)∈Σ
1
n (n≥1),and note that by
part(ii)of the Theorem,there exists,for each n,γn>0such that(ωn,γn)∈χ0.By the de?nition ofχ0there exists u n∈Σ0such thatγn=Φ(ω?1n,u n). But by Lemma12we haveγn→0as n→∞.Hence we have(ωn,γn)→(0,0), so we have(0,0)∈
2
<1
then F(λ,.):Z→Y(hence also F(λ,.):Z→Z)is a contraction.
proof:Computing the Frech′e t derivative of N:Z→Z we have
N′(u)(v)=cos(z+u(z))v(z)?
1
2
?u∈Z, which,by(47),completes the proof.
Lemma14.Fixingα≥0,β>0,there existsλ0>0such that for any λ∈[0,λ0)the equation(34)has a unique solution,which we denote by uλ. The mappingλ→uλfrom[0,λ0)into Z is continuous and is real-analytic forλ∈(0,λ0).
proof:It is easy to see that we can?ndλ0>0such that(47)holds for λ∈[0,λ0),and thus by Lemma13,for anyλ∈[0,λ0)the mapping F(λ,.): Z→Z is a contraction,so that,by Banach’s?xed-point Theorem,equation (34)has a unique solution,which we denote by uλ.Real-analyticity of the mappingλ→uλfollows from the real-analytic implicit function Theorem.
12GUY KATRIEL
Returning to the proof of part(v)of Theorem4,we note that since, by Lemma11,for eachλthere exists u such that(λ,u)∈Σ0,and since the uniqueness in Lemma14implies that whenλ<λ0such a u is unique inΣ, we must have
(50)0<λ<λ0,(λ,u)∈Σ?(λ,u)∈Σ0.
Thus if we setω0=1
2π 2π0sin(s+u(s))ds>0.
The strictness in the above inequality follows from the fact that,by (22),if we had equality this would imply u=0,but it is easy to check that (λ,0)∈Σforλ>0.
3.More on the bias-frequency characteristic
In this section we prove Theorem6,which shows that for a certain open subset of the space of parameters L,α,β,the bias-frequency characteristicχis a connected,real analytic curve,and can be represented as the graph of a function:γ=
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS13 The condition k>1ensures that the quadratic function p(μ)has a minimum, and we have p(0)=1>0.Moreover the condition(9)ensures that p′(0)≥0, which implies p is increasing on[0,∞),so that(54)holds.We thus obtain a unique solution uλto(34).The fact that it is real-analytic inλ∈(0,∞) follows from the analytic implicit function Theorem and the fact that the
functionλ→L?1
λfrom(0,∞)to the space B(Z)of bounded linear operators
from Z to itself is real-analytic.
Let us note here that it is precisely the last statement in the above proof
-the fact thatλ→L?1
λis real-analytic,that breaks down whenβ=0,and
is responsible for the fact that in that case(i.e.the case of the damped,dc-forced sine-Gordon equation)the curveχis not smooth(see[10],?g.2).The
reason that,whenβ=0,λ→L?1
λis not real-analytic can be gleaned by
recalling the de?nition(25):ifβ=0then atλ=1γ(ω)=Ψ(ω?1)we have(10).The fact that
14GUY KATRIEL
To prove claim(57)we note that,
since
Ψ(λ)=α
2π 2π0sin(s+uλ(s))ds,
we have
Ψ′(λ)=?α
2π 2π0cos(s+uλ(s))Dλuλ(s)ds,
and using Cauchy’s inequality (58)Ψ′(λ)≤?
α
λ2)asλ→0+.In fact
we shall prove a much stronger statement:
Lemma17.We have
(59) Dλuλ Z=O(λ)asλ→0+.
proof:We di?erentiate the identity
Lλ(uλ)=λN(uλ)
with respect toλ,obtaining
(60)(DλLλ)(uλ)+Lλ(Dλuλ)=N(uλ)+λN′(uλ)(Dλuλ).
We note that,because we assumeλ∈(0,λ0),whereλ0is de?ned as in
Lemma14,λL?1
λN′(uλ)is a contraction from Z to itself so the inverse of
I?λL?1
λN′(uλ)is well de?ned as a mapping from Z to itself.Moreover we
have,using(49),
(61)
[I?λL?1λN′(uλ)]?1 Z,Z≤1
2π 2π0cos2(s+uλ(s))(1+u′λ(s))2ds 1
2π 2π0(1+u′λ(s))2ds
12≤ 1+ λ22,
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS15
so that
(63) N(uλ) Y=O(1)asλ→0+.
From(32)and(63)we have
(64)
L?1λN(uλ) Z≤ L?1λN(uλ) X≤ L?1λ Y,X N(uλ) Y=O(λ)asλ→0+.
From the de?nition(25)of Lλwe have,for all u∈X
(DλLλ)(u)= k2+1
λ2 u X?u∈X.
From(64)we have
(66) uλ X=λ L?1λN(uλ) X=O(λ2)asλ→0+,
so using(65),(66)
(67) (DλLλ)(uλ) Y=O(1)asλ→0+,
and together with(32)
(DλLλ)(uλ) Z≤ L?1λ(DλLλ)(uλ) X=O(λ)asλ→0+.
(68) L?1
λ
Using(61),(62),(64)and(68)we obtain(59).
5.multiplicity of rotating fluxon waves
In this section we prove Theorem8,which shows that for some values of the parameters L,β,ifα>0is su?ciently small then there exists an interval ofγ’s for which there exist at least three rotating?uxon waves.
Lemma18.Assume thatβ>0and(8),(14)hold.Then for anyα≥0,λ≥0,the equation(34)has a unique solution,which we denote by uα,λ. The mapping(α,λ)→uα,λfrom[0,∞)×[0,∞)into Z is continuous.
As in the proof of Lemma16,this follows from the Banach?xed point Theorem applied to(34).Note that(14)implies that(9)holds for allα≥0.
Since in the following argument the dependence onαis important,we display it in the notation(of course uα,λalso depends on the parameters k and β,but since we shall regard these as?xed we can suppress this dependence). proof of Theorem8:Under the conditions of Lemma18we can de?ne Ψα(λ)as in(55),now de?ned for allλ∈[0,∞),so that rotating?uxon waves correspond to solutions of
(69)Ψα(λ)=γ,λ>0.
16GUY KATRIEL
We write Ψα(λ)in the form (see (28))(70)Ψα(
λ)
=α2
π 2π
sin(s +u α,λ(s ))ds.We note some properties of the function Υα(λ)(valid for any α≥0).Since u α,0=0we have
(71)
Υα(0)=0.From (46)we obtain:
(72)
lim λ→+∞Υα(λ)=0.Lemma 15implies
(73)Υα(λ)>0?λ>0.
(71),(72),(73),imply that Υα(λ)attains a positive global maximum at some λ>0.In particular this is true for α=0,and we denote the global maximum of Υ0(λ)by γ0,and assume that it is attained at λ0>0:
(74)Υ0(λ0)=γ0=max λ>0
Υ0(λ).We now ?x an arbitrary 0
14,Υ0(λ2)
2
?α∈[0,α0],λ∈[0,λ2].From (74),(75)and (76)we obtain,for all α∈[0,α0],
(77)Υα(λ0)>γ0?
?4?,Υα(λ2)<
3
λ1<
?2?α∈[0,α0],λ≥λ1.
FLUXON WA VES IN ANNULAR JOSEPHSON JUNCTIONS17
Together with(77),(78)this gives,for all0<α<α0,
(80)Ψα(λ0)>γ0??,
(81)Ψα(λ1)
(82)Ψα(λ2)
and by(70)we also have
(83)lim
Ψα(λ)=+∞.
λ→0+
Thus by continuity ofΨαon(0,∞),if we takeγ∈(?,γ0??)then by(83)and (81)the equation(69)has a solutionλ∈(0,λ1),by(81)and(80)the equation (69)has a solutionλ∈(λ1,λ0),and by(80)and(82)the equation(69)has a solutionλ∈(λ1,λ2).We have thus found,under the stated assumptions,three solutions of(69),corresponding to three rotating?uxon waves with di?erent frequencies.
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Einstein Institute of Mathematics,The Hebrew University of Jerusalem, Jerusalem,91904,Israel
E-mail address:haggaik@https://www.doczj.com/doc/7912662230.html,
中文： 共同保密协议 ABC公司（以下称为ABC），其总部设于—，与XYZ（以下称为XYZ），其总部设于—，鉴于本协议的共同契约条款，谨达成如下协议： 1.在协议双方有关策略性联盟（此后称为“主题事项事项”）的磋商问题上，本协议一方可以在保密的基础上向另一方披露其专有资讯（此后称为“资讯”），披露方可以认为该等资讯具有专有性，因为披露方是在协议双方内部披露了该资讯，或因为披露方在接受“资讯”的同时已经承担了为“资讯”继续保密的义务，或由于其它的原因。 2.当被视为专有的“资讯”以载体的形式被提供时，披露方须以对“资讯”进行标记的方式，指出该资讯的专有性或机密性，或者把该资讯的传布局限在协议所规定的范围里。当“资讯”被口头提供时，提供方在披露的同时，应明确声明其专有性或机密性，或者把该资讯的传布限制在协议规定范围里，或者，事后立即书面确认该资讯的专有性和机密性。此外，该协议之实体和条款，双方就“主题事项事项”所进行磋商的事实和内容以及相关“主题事项事项”的通信都被将认为具有专有性。 3.关于该协议所披露的“资讯”，获披露“资讯”的一方，其职员及其附属公司的职员应该做到： a.对该资讯保密，其采取的谨慎程度不少于披露方为保护其不愿披露的专有机密资讯所采取的谨慎程度，并且，在任何情况下，以合理的谨慎程度进行保密。 b.把资讯的披露范围仅仅局限于董事会、公司高级职员、职员和/或有必要知道的代理/顾问，不得将资讯披露给其他任何人。 c.建议获披露该“资讯”之人士履行对该资讯的保密义务。 d.仅仅将该资讯用于有关“主题事项事项”的通信和磋商上，除此以外使用该资讯必须经双方书面同意。 4.获披露“资讯”一方想要将“资讯”披露给非附属的顾问和代理，必须首先经由“资讯”原本披露方的书面认可，并且与该顾问和代理签署有关保密协议，其形式必须为“资讯”原本披露方所满意。 5.“资讯”应被视为资讯披露方的财产，一旦该方要求，另一方应以载体的形式把所有“资讯”归还给披露方，或者按照资讯披露方的指示销毁该资讯。如另一方丢失了“资讯”或者在未经授权的情况下披露了“资讯”，应立即通知对方并作合理的努力来追回丢失或错误地泄露了的资讯。 6.在下述情况下，获披露“资讯”的一方没有任何义务来保持该资讯的专有性： a.此前已为不受保密性义务约束的一方获知，或 b.即便不存在未经授权的披露该资讯也可以或者将可以逐渐为公众所悉，或
脐带间充质干细胞的研究进展 间充质干细胞（mesenchymal stem cells,MSC S ）是来源于发育早期中胚层 的一类多能干细胞[1-5]，MSC S 由于它的自我更新和多项分化潜能，而具有巨大的 治疗价值 ,日益受到关注。MSC S 有以下特点：(1)多向分化潜能，在适当的诱导条件下可分化为肌细胞[2]、成骨细胞[3、4]、脂肪细胞、神经细胞[9]、肝细胞[6]、心肌细胞[10]和表皮细胞[11, 12]；(2)通过分泌可溶性因子和转分化促进创面愈合；(3) 免疫调控功能，骨髓源（bone marrow ）MSC S 表达MHC-I类分子，不表达MHC-II 类分子，不表达CD80、CD86、CD40等协同刺激分子，体外抑制混合淋巴细胞反应，体内诱导免疫耐受[11, 15]，在预防和治疗移植物抗宿主病、诱导器官移植免疫耐受等领域有较好的应用前景；(4)连续传代培养和冷冻保存后仍具有多向分化潜能，可作为理想的种子细胞用于组织工程和细胞替代治疗。1974年Friedenstein [16] 首先证明了骨髓中存在MSC S ，以后的研究证明MSC S 不仅存在于骨髓中，也存在 于其他一些组织与器官的间质中：如外周血[17]，脐血[5]，松质骨[1, 18]，脂肪组织[1]，滑膜[18]和脐带。在所有这些来源中，脐血(umbilical cord blood)和脐带(umbilical cord)是MSC S 最理想的来源，因为它们可以通过非侵入性手段容易获 得，并且病毒污染的风险低，还可冷冻保存后行自体移植。然而，脐血MSC的培养成功率不高[19, 23-24]，Shetty 的研究认为只有6%，而脐带MSC的培养成功率可 达100%[25]。另外从脐血中分离MSC S ，就浪费了其中的造血干/祖细胞(hematopoietic stem cells/hematopoietic progenitor cells,HSCs/HPCs) [26, 27]，因此，脐带MSC S (umbilical cord mesenchymal stem cells, UC-MSC S )就成 为重要来源。 一．概述 人脐带约40 g, 它的长度约60–65 cm, 足月脐带的平均直径约1.5 cm[28, 29]。脐带被覆着鳞状上皮，叫脐带上皮，是单层或复层结构，这层上皮由羊膜延续过来[30, 31]。脐带的内部是两根动脉和一根静脉，血管之间是粘液样的结缔组织，叫做沃顿胶质，充当血管外膜的功能。脐带中无毛细血管和淋巴系统。沃顿胶质的网状系统是糖蛋白微纤维和胶原纤维。沃顿胶质中最多的葡萄糖胺聚糖是透明质酸，它是包绕在成纤维样细胞和胶原纤维周围的并维持脐带形状的水合凝胶，使脐带免受挤压。沃顿胶质的基质细胞是成纤维样细胞[32]，这种中间丝蛋白表达于间充质来源的细胞如成纤维细胞的，而不表达于平滑肌细胞。共表达波形蛋白和索蛋白提示这些细胞本质上肌纤维母细胞。 脐带基质细胞也是一种具有多能干细胞特点的细胞，具有多项分化潜能，其 形态和生物学特点与骨髓源性MSC S 相似[5, 20, 21, 38, 46]，但脐带MSC S 更原始，是介 于成体干细胞和胚胎干细胞之间的一种干细胞，表达Oct-4, Sox-2和Nanog等多
外阴白色病变考试试题 一、A1型题（本大题11小题．每题1.0分，共11.0分。每一道考试题下面有A、 B、C、D、E五个备选答案。请从中选择一个最佳答案，并在答题卡上将相应题号的相应字母所属的方框涂黑。） 第1题 外阴硬化性苔癣的早期病理改变是 A 表层细胞过度角化 B 表层细胞增生 C 真皮乳头层水肿 D 毛囊角质栓塞 E 底层细胞增生 【正确答案】：C 【本题分数】：1.0分 第2题 女，50岁。因外阴瘙痒而就医，组织病理为增生型，营养不良，下列治疗中哪项是正确的 A 因有恶变趋向，应及早手术治疗 B 全身治疗 C 补充多量维生素 D 活检有非典型增生时手术治疗 E 全身+局部治疗 【正确答案】：D 【本题分数】：1.0分 第3题 关于外阴瘙痒下列哪项是正确的 A 外阴瘙痒是外阴癌的早期表现 B 外阴瘙痒最常见的原因是蛲虫病
C 外阴瘙痒严重时用肥皂液清洗会有所好转 D 外阴瘙痒经治疗无效应作单纯性外阴切除术 E 外阴瘙痒不是一种疾病而是多种疾病可引起的一种症状 【正确答案】：E 【本题分数】：1.0分 第4题 女，37岁。外阴奇痒，分泌物不多。妇检：两侧小阴唇增厚，外阴粘膜不红，阴道畅，皱襞正常，无异常分泌物，宫颈柱状，光滑，I°肥大，子宫前位，常大，双附件(-)，为确诊应选用 A 外阴活检 B 阴道分泌物涂片 C 宫颈涂片(CG D 阴道镜 E 盆腔B超 【正确答案】：A 【本题分数】：1.0分 第5题 属于癌前病变的外阴白色病变是 A 增生型营养不良 B 硬化苔癣型营养不良 C 混合型营养不良 D 营养不良伴有上皮不典型增生 E 白癜风 【正确答案】：D 【本题分数】：1.0分 第6题
精神分裂症的病因及发病机理 精神分裂症病因：尚未明，近百年来的研究结果也仅发现一些可能的致病因素。（一）生物学因素1．遗传遗传因素是精神分裂症最可能的一种素质因素。国内家系调查资料表明：精神分裂症患者亲属中的患病率比一般居民高6.2倍，血缘关系愈近，患病率也愈高。双生子研究表明：遗传信息几乎相同的单卵双生子的同病率远较遗传信息不完全相同 的双卵双生子为高，综合近年来11项研究资料：单卵双生子同病率（56.7%），是双卵双生子同病率（12.7%）的4.5倍，是一般人口患难与共病率的35-60倍。说明遗传因素在本病发生中具有重要作用，寄养子研究也证明遗传因素是本症发病的主要因素，而环境因素的重要性较小。以往的研究证明疾病并不按类型进行遗传，目前认为多基因遗传方式的可能性最大，也有人认为是常染色体单基因遗传或多源性遗传。Shields发现病情愈轻，病因愈复杂，愈属多源性遗传。高发家系的前瞻性研究与分子遗传的研究相结合，可能阐明一些问题。国内有报道用人类原癌基因Ha-ras-1为探针，对精神病患者基因组进行限止性片段长度多态性的分析，结果提示11号染色体上可能存在着精神分裂症与双相情感性精神病有关的DNA序列。2．性格特征：约40%患者的病前性格具有孤僻、冷淡、敏感、多疑、富于幻想等特征，即内向
型性格。3．其它：精神分裂症发病与年龄有一定关系，多发生于青壮年，约1/2患者于20～30岁发病。发病年龄与临床类型有关，偏执型发病较晚，有资料提示偏执型平均发病年龄为35岁，其它型为23岁。80年代国内12地区调查资料：女性总患病率（7.07%。）与时点患病率（5.91%。）明显高于男性（4.33%。与3.68%。）。Kretschmer在描述性格与精神分裂症关系时指出：61%患者为瘦长型和运动家型，12.8%为肥胖型，11.3%发育不良型。在躯体疾病或分娩之后发生精神分裂症是很常见的现象，可能是心理性生理性应激的非特异性影响。部分患者在脑外伤后或感染性疾病后发病；有报告在精神分裂症患者的脑脊液中发现病毒性物质；月经期内病情加重等躯体因素都可能是诱发因素，但在精神分裂症发病机理中的价值有待进一步证实。（二）心理社会因素1．环境因素①家庭中父母的性格，言行、举止和教育方式（如放纵、溺爱、过严）等都会影响子女的心身健康或导致个性偏离常态。②家庭成员间的关系及其精神交流的紊乱。③生活不安定、居住拥挤、职业不固定、人际关系不良、噪音干扰、环境污染等均对发病有一定作用。农村精神分裂症发病率明显低于城市。2．心理因素一般认为生活事件可发诱发精神分裂症。诸如失学、失恋、学习紧张、家庭纠纷、夫妻不和、意处事故等均对发病有一定影响，但这些事件的性质均无特殊性。因此，心理因素也仅属诱发因
外阴疾病 外阴：阴道口外边的外露部分肛门、阴道口及尿道邻近，经常受阴道分泌物及尿液的浸渍，容易发炎。 常见病症：外因瘙痒、外阴炎、外阴白色病变、外因溃疡、外阴癌 外阴疾病 外阴：阴道口外边的外露部分肛门、阴道口及尿道邻近，经常受阴道分泌物及尿液的浸渍，容易发炎。 常见病症：外因瘙痒、外阴炎、外阴白色病变、外因溃疡、外阴癌 外因瘙痒 外阴瘙痒是妇科疾病中很常见的一种症状，外阴是特别敏感的部位，妇科多种病变及外来刺激均可引起瘙痒，使人寝食难安、坐卧不宁。外阴瘙痒多发生于阴蒂、小阴唇，也可波及大阴唇、会阴和肛周 病因：1.慢性局部刺激，外阴、阴道、宫颈炎症的异常分泌物的刺激； 2.外阴不清洁及紧身化纤内裤、卫生巾等致通透不良； 3.外阴寄生虫病，如阴虱、蛲虫、疥疮等； 4.各种外阴皮肤病和外阴肿瘤等； 5.全身性疾病的外阴局部症状，如糖尿病、尿毒症、维生素缺乏等。 症状：外因皮肤瘙痒、烧灼感和疼痛瘙痒部位多生与阴帝、小阴唇、也可波及大阴、会阴、甚至肛周围 危害：(1)性外阴部瘙痒严重时，不但使人坐卧不宁，影响工作、学习、生活和睡眠。 (2)由于女性外阴瘙痒，会影响夫妻生活，所以极有导致夫妻感情不和，严重的 甚至造成感情破裂，婚姻走向终点。 (3)诱发生殖器感染，盆腔炎、肾周炎、性交痛等，日久不愈还可导致多种疾病 同时发生，疾病的危害严重的会危害女性健康，甚至还会造成女性不孕等严重后果。 (4)女性外阴瘙痒严重时，不易根治，易反复，引发早产、胎儿感染畸形等，造 成终身遗憾。 治疗1.外阴涂药
使用有止痒作用的洗剂、膏霜等，如炉甘石洗剂、苯海拉明软膏、皮质醇类软膏等。 2.局部封闭或穴位注药 如皮质醇激素、维生素B12、非那根等。 3.针对病因治疗。 4.预防1. 注意经期卫生，勤清洗。 2.不要冲洗阴道，因为阴道有自清的功能，如果刻意冲洗反而不利 3.忌乱用、烂用药物，忌抓搔及局部摩擦。 4.忌酒及辛辣食物，不吃海鲜等及易引起过敏的药物 6 .久治不愈者应作血糖检查。少吃糖类可避免常常感染霉菌，如少吃淀粉类、糖类以及刺激性的食物(例如酒、辛辣物、油炸类)，多吃蔬菜水果类，水份要充足。 5、不穿紧身兜裆裤，内裤更须宽松、透气，并以棉制品为宜。 6.就医检查是否有霉菌或滴虫，如有应及时治疗，而不要自己应用“止痒水”治疗。 8.保持外阴清洁干燥，尤其在经期、孕期、产褥期，每天用女性护理液清洗外阴更换内裤。 9.不穿化纤内裤、紧身裤，着棉织内衣裤。局部坐浴时注意溶液浓度、温度及时间、注意事项。 10.外阴瘙痒者应勤剪指甲、勤洗手，不要搔抓皮肤，以防破溃感染从而继发细菌性感染。 11.上完厕所请记得由前往后擦，因为肛门可能会带来不少细菌，所以如厕后请不要由肛门擦到阴部，才能减少感染的机会。 12.内裤要和其他的衣物分开洗，最好暴晒，可以减少细菌的滋生。如果患有霉菌性阴道炎的话，最好内裤都有热水煮 外阴溃疡外阴溃疡是发生于外阴部的皮肤黏膜发炎、溃烂、缺损。病灶多发生于小阴唇和大阴唇内侧，其次为前庭黏膜及阴道口周围。病程有急性及慢性。 大小阴唇、阴道口周围、阴蒂等处（外阴疾病发展中出现的一个过程，不是一个独立的疾病，有急性和慢性）急性外阴溃疡：非特异性外阴炎病情较轻，多在搔抓之后出现一般比较表浅，但疼痛比较厉害 慢性外阴溃疡：持续时间较长，或者反复发作 癌症引起的溃疡，与结核性溃疡很难鉴别，需做确诊
Three months later FFCC had suddenly been dissolved with no reasons given. One could assume that Withers and his associates were now in disgrace, but there had been no report of the matter in the Press or on the telescreen. That was to be expected, since it was unusual for political offenders to be put on trial or even publicly denounced. The great purges involving thousands of people, with public trials of traitors and thought-criminals who made abject confession of their crimes and were afterwards executed, were special show-pieces not occurring oftener than once in a couple of years. More commonly, people who had incurred the displeasure of the Party simply disappeared and were never heard of again. One never had the smallest clue as to what had happened to them. In some cases they might not even be dead. Perhaps thirty people personally known to Winston, not counting his parents, had disappeared at one time or another. Winston stroked his nose gently with a paper-clip. In the cubicle across the way Comrade Tillotson was still crouching secretively over his speakwrite. He raised his head for a moment: again the hostile spectacle-flash. Winston wondered whether Comrade Tillotson was engaged on the same job as himself. It was perfectly possible. So tricky a piece of work would never be entrusted to a single person: on the other hand, to turn it over to a committee would be to admit openly that an act of fabrication was taking place. V ery likely as many as a dozen people were now working away on rival versions of what Big Brother had actually said. And presently some master brain in the Inner Party would select this version or that, would re-edit it and set in motion the complex processes of cross-referencing that would be required, and then the chosen lie would pass into the permanent records and become truth. Winston did not know why Withers had been disgraced. Perhaps it was for corruption or incompetence. Perhaps Big Brother was merely getting rid of a too-popular subordinate. Perhaps Withers or someone close to him had been suspected of heretical tendencies. Or perhaps -- what was likeliest of all -- the thing had simply happened because purges and vaporizations were a necessary part of the mechanics of government. The only real clue lay in the words 'refs unpersons', which indicated that Withers was already dead. You could not invariably assume this to be the case when people were arrested. Sometimes they were released and allowed to remain at liberty for as much as a year or two years before being executed. Very occasionally some person whom you had believed dead long since would make a ghostly reappearance at some public trial where he would implicate hundreds of others by his testimony before vanishing, this time for ever. Withers, however, was already an unperson. He did not exist: he had never existed. Winston decided that it would not be enough simply to reverse the tendency of Big Brother's speech. It was better to make it deal with something totally unconnected with its original subject. He might turn the speech into the usual denunciation of traitors and thought-criminals, but that was a little too obvious, while to invent a victory at the front, or some triumph of over-production in the Ninth Three-Year Plan, might complicate the records too much. What was needed was a piece of pure fantasy. Suddenly there sprang into his mind, ready made as it were, the image of a certain Comrade Ogilvy, who had recently died in battle, in heroic circumstances. There were occasions when Big Brother devoted his Order for the Day to commemorating some humble, rank-and-file Party member whose life and death he held up as an example worthy to be followed. Today he should commemorate Comrade Ogilvy. It was true that there was no such person as
脐带血造血干细胞库管理办法（试行） 第一章总则 第一条为合理利用我国脐带血造血干细胞资源，促进脐带血造血干细胞移植高新技术的发展，确保脐带血 造血干细胞应用的安全性和有效性，特制定本管理办法。 第二条脐带血造血干细胞库是指以人体造血干细胞移植为目的，具有采集、处理、保存和提供造血干细胞 的能力，并具有相当研究实力的特殊血站。 任何单位和个人不得以营利为目的进行脐带血采供活动。 第三条本办法所指脐带血为与孕妇和新生儿血容量和血循环无关的，由新生儿脐带扎断后的远端所采集的 胎盘血。 第四条对脐带血造血干细胞库实行全国统一规划，统一布局，统一标准，统一规范和统一管理制度。 第二章设置审批 第五条国务院卫生行政部门根据我国人口分布、卫生资源、临床造血干细胞移植需要等实际情况，制订我 国脐带血造血干细胞库设置的总体布局和发展规划。 第六条脐带血造血干细胞库的设置必须经国务院卫生行政部门批准。 第七条国务院卫生行政部门成立由有关方面专家组成的脐带血造血干细胞库专家委员会（以下简称专家委
员会），负责对脐带血造血干细胞库设置的申请、验收和考评提出论证意见。专家委员会负责制订脐带血 造血干细胞库建设、操作、运行等技术标准。 第八条脐带血造血干细胞库设置的申请者除符合国家规划和布局要求，具备设置一般血站基本条件之外， 还需具备下列条件： （一）具有基本的血液学研究基础和造血干细胞研究能力； （二）具有符合储存不低于1 万份脐带血的高清洁度的空间和冷冻设备的设计规划； （三）具有血细胞生物学、HLA 配型、相关病原体检测、遗传学和冷冻生物学、专供脐带血处理等符合GMP、 GLP 标准的实验室、资料保存室； （四）具有流式细胞仪、程控冷冻仪、PCR 仪和细胞冷冻及相关检测及计算机网络管理等仪器设备； （五）具有独立开展实验血液学、免疫学、造血细胞培养、检测、HLA 配型、病原体检测、冷冻生物学、 管理、质量控制和监测、仪器操作、资料保管和共享等方面的技术、管理和服务人员； （六）具有安全可靠的脐带血来源保证； （七）具备多渠道筹集建设资金运转经费的能力。 第九条设置脐带血造血干细胞库应向所在地省级卫生行政部门提交设置可行性研究报告，内容包括：
Epic史诗 An epic is a long narrative poem in a formal and elevated style about the achievements of a central hero who usually embodies national ideals. Alliteration 头韵 In alliterative verse, certain accented words in a line begin with the same consonant sound. Heroic couplet英雄双韵体 Lines of iambic pentameter rhymed in pairs: aa, bb, cc, and so on. （英雄双韵体：以五步抑扬格为基本节奏，每两行押韵，铿锵有力。） Iambic Pentameter 五音步抑扬格 A poetic line consisting of five verse feet (音步) with each foot an iamb (抑扬格). Iambic: a pattern of alternating unstressed and stressed syllables, an unstressed syllable followed by a stressed syllable. Folk/Popular Ballad 民谣 A ballad is a story told in song, usually in 4-line stanzas, with the second and fourth lines rhymed. Legend 民间传说 A song or narrative handed down from the past. Arthurian legend 亚瑟王王传奇 It is a group of tales developed in the Middle Ages concerning King Arthur and his knights. Canto 长诗的篇章，诗章 A section or division of a long poem. Romance 传奇故事 It was a long composition, sometimes in verse, sometimes in prose, describing the life and adventures of a noble hero. Ballad 大众民谣 A ballad is a long song or poem which tells a story in simple language. Humanism人文主义 Humanism is defined as a moral and political view based on the worldly existence of man, his all-round development, his worldly life and happiness. Spenserian Stanza斯宾塞诗体 Each stanza has nine lines, eight of iambic pentameter followed by one of iambic hexameter(六音步), with the rhyme scheme ababbcbcc. Blank verse 无韵诗 verse written in rhymeless iambic pentameter. Sonnet 十四行诗 A sonnet is a poem of 14-lines, usually in iambic pentameter with various rhyming schemes. Essay 随笔 A piece of prose writing, usually short, that deals with a subject in a limited way and expresses a particular point of view. An essay can be formal, with thorough, serious, and highly organized content; or informal, with a humorous or personal tone and less rigid structure. Elegy 挽歌 An elaborately formal lyric poem lamenting the death of a friend or public figure, or reflecting seriously on a solemn subject.
外阴白色病变的症状表现有哪些 外阴白色病变是慢性外阴的营养不良。属于营养不良的一种。而这也有分为好几个类型，混合型、增生型和硬化苔藓型等等都是外阴白色病变的类型。 外阴奇痒为主要症状，搔痒时间从发病到治疗有2～3月之内，也有达20 年之久，搔痒剧烈程度不分季节与昼夜，如伴有滴虫性或霉菌性阴道炎，分泌物会更多，局部烧灼感，刺痛与搔痒所致的皮肤粘膜破损或感染有关，局部有不同程度的皮肤粘膜色素减退，常有水肿，皲裂及散在的表浅溃疡。 一、增生型营养不良 一般发生在30～60岁的妇女，主要症状为外阴奇痒难忍，抓伤后疼痛加剧，病变范围不一，主要波及大阴唇，阴唇间沟，阴蒂包皮和后联合处，多呈对称性，病变皮肤增厚似皮革，隆起有皱襞，或有鳞屑，湿疹样改变，表面颜色多暗红或粉红，夹杂有界限清晰的白色斑块，一般无萎缩或粘连。 二、硬化苔藓型营养不良 可见于任何年龄，多见于40岁左右妇女，主要症状为病变区发痒，但一般远较增生型病变为轻，晚期出现性交困难，病变累及外阴皮肤，粘膜和肛周围皮肤，除皮肤或粘膜变白，变薄，干燥易皲裂外，并失去弹性，阴蒂多萎缩，且与包皮粘连，小阴唇平坦消失，晚期皮肤菲薄皱缩似卷烟纸，阴道口挛缩狭窄，仅容指尖。 幼女患此病多在小便或大便后感外阴及肛周不适，外阴及肛周区出现锁孔状珠黄色花斑样或白色病损，一般至青春期时，病变多自行消失。 三、混合型营养不良 主要表现为菲薄的外阴发白区的邻近部位，或在其范围内伴有局灶性皮肤增厚或隆起。 四、增生型或混合型伴上皮非典型增生 一般认为在增生型及混合型病变中，仅5、10例可出现非典型增生，且此非典型增生仅限于增生的上皮细胞部分。非典型增生多无特殊临床表现，局部组织活体组织检查为唯一的诊断方法。但如外阴局部出现溃疡。或界限清楚的白色隆起时，在该处活检发现非典型增生，其癌变的可能性较大。
精神分裂症的发病原因是什么 精神分裂症是一种精神病，对于我们的影响是很大的，如果不幸患上就要及时做好治疗，不然后果会很严重，无法进行正常的工作和生活，是一件很尴尬的事情。因此为了避免患上这样的疾病，我们就要做好预防，今天我们就请广州协佳的专家张可斌来介绍一下精神分裂症的发病原因。 精神分裂症是严重影响人们身体健康的一种疾病，这种疾病会让我们整体看起来不正常，会出现胡言乱语的情况，甚至还会出现幻想幻听，可见精神分裂症这种病的危害程度。 (1)精神刺激：人的心理与社会因素密切相关，个人与社会环境不相适应，就产生了精神刺激，精神刺激导致大脑功能紊乱，出现精神障碍。不管是令人愉快的良性刺激，还是使人痛苦的恶性刺激，超过一定的限度都会对人的心理造成影响。 (2)遗传因素：精神病中如精神分裂症、情感性精神障碍，家族中精神病的患病率明显高于一般普通人群，而且血缘关系愈近，发病机会愈高。此外，精神发育迟滞、癫痫性精神障碍的遗传性在发病因素中也占相当的比重。这也是精神病的病因之一。 (3)自身：在同样的环境中，承受同样的精神刺激，那些心理素质差、对精神刺激耐受力低的人易发病。通常情况下，性格内向、心胸狭窄、过分自尊的人，不与人交往、孤僻懒散的人受挫折后容易出现精神异常。 (4)躯体因素：感染、中毒、颅脑外伤、肿瘤、内分泌、代谢及营养障碍等均可导致精神障碍，。但应注意，精神障碍伴有的躯体因素，并不完全与精神症状直接相关，有些是由躯体因素直接引起的，有些则是以躯体因素只作为一种诱因而存在。 孕期感染。如果在怀孕期间，孕妇感染了某种病毒，病毒也传染给了胎儿的话，那么，胎儿出生长大后患上精神分裂症的可能性是极其的大。所以怀孕中的女性朋友要注意卫生，尽量不要接触病毒源。 上述就是关于精神分裂症的发病原因，想必大家都已经知道了吧。患上精神分裂症之后，大家也不必过于伤心，现在我国的医疗水平是足以让大家快速恢复过来的，所以说一定要保持良好的情绪。
逻辑错误一览-全了!----这个必看啊---
逻辑错误一览-全了!----这个必看啊---
逻辑错误一览，全了！无论你是打辩论赛，考TOEFL、GRE，还是想提高自己的逻辑思维，甚至是更想有水平地骂人~~~ 这个必看啊~~~2013年08月01日13:15:00 来自：人人网赖若麒.avi的日志 * 当你与别人讨论，尝试获得答案或解释时，你可能会遇到一些人犯上逻辑谬误。这样的讨论是无意义的。你可能尝试向对手要求证据或提供其他假设，令你获得更好或更简单的解释。如果都失败，可以尝试指出你讨论对手的问题。你可辨认他的逻辑问题以免深究，以及可告知讨论对手关於他的谬误。以下是简单介绍其中最常见的谬误： 人身攻击（ad hominem） o 拉丁语「向着人」的意思。辩者用人身攻击来攻击对手，而不是在讨论议题。当辩者不能用证据、事实或理由去维护他的立场，他可能透过标签、稻草人、骂人、挑衅及愤怒的人身攻击方式来攻击对手。 诉诸无知（appeal to ignorance / argumentum ex silentio） o 以诉诸无知作为某些证据。（例如：我们没有证据说神不存在，所以祂一定存在。又例如：由於我们没有关於外星人的知识，这表示他们并不存在。）对某些东西的无知，是与它的存在与否无关。 全知论据（argument from omniscience） o （例如：所有人都相信某些东西，每个人都知道的。）辩者需要有全知能力以清楚每个人的信仰、怀疑或他们的知识。小心如「所有」、「每个人」、「每种东西」、「绝对」等词语。 诉诸信心（appeal to faith） （例如：如果你不相信，是不能清楚明白的。）如果辩者倚仗信心作为他论据的根基，那麽你在以後的讨论所能得到的将不多。根据定义，「信心」是倚靠相信，并非靠逻辑或证据支持。信心倚赖非理性的思想，并会产生不妥协。 诉诸传统（appeal to tradition） （类似主流思想谬误）（例如：占星、宗教、奴隶）只因为人们以此为传统，与它本身的存活能力无关。 诉诸权威（argument from authority / argumentum ad verecundiam）* 以「专家」或权威的说话作论据的根基，而不是用逻辑或证据来支持该论据。（例如：某某教授相信创造科学。）只由於某个权威的声称，不足以代表他已令这声称正确。假如辩者展示某专家的论据，那麽看看它有否伴随着原因，以及它背後证据的来源。
外阴白色病变的检查诊断方法是什么 外阴奇痒是外阴白色病变的主要症状，搔痒时间从发病到治疗有2～3月之内，也有达20年之久，搔痒剧烈程度不分季节与昼夜。专家提示，一旦发现自己有类似于外阴白色病变的这种，应立即到医院进行确诊。早期的诊断及治疗对我们早日恢复健康并且尤为重要。 外阴白色病变的检查： 多点活检送病理检查，确定病变性质，排除早期癌变，活检应在有皲裂，溃疡，隆起，硬结或粗糙处进行，为做到取材适当，可先用1%甲苯胺蓝(toluidine blue)涂病变区，待白干后，再用1%醋酸液擦洗脱色，凡不脱色区表示该处有裸核存在，提示在该处活检，发现非典型增生或甚至癌变的可能性较大，如局部破损区太广，应先治疗数日，待皮损大部愈合后，再选择活检部位以提高诊断准确率。 外阴白色病变的诊断： 1、症状判断：外阴白斑一般根据症状就可以判断，比如，外阴局部粘 膜发白，瘙痒、粗糙、脱屑等现象的出现，都会诊断为外阴白斑，当然，外阴白斑有很多的类型，如果外阴白斑属于增生型，也就是说局部的皮肤粘膜增厚了，弹性变差了，而且也出现了相应的溃疡等不适症状。这是主要的外阴白斑的诊断方法。 2、细胞活检：有时外阴白斑的诊断需要进一步的做细胞活检，观察有 没有癌细胞，以便于确诊。活检病理检查确定病变性质，排除早期癌变。活检应在有皲裂溃疡、隆起、硬结或粗糙处进行为做到取材适当，外阴白斑的诊断方法可先用1%甲苯胺蓝涂病变区，待白干后再用1%醋酸液擦洗脱色。凡不脱色区表示该处有裸核存在，提示在该处活检发现非典型增生或甚至癌变的可能性较大。如局部破损区太广，应先治疗数日待皮损大部愈合后，再选择活检部位以提高诊断准确率。 3、病理诊断依据：除了解疾病的主要临床症状外，还应对疾病的发病 机理有一定的认识，因为导致外阴白斑皮肤瘙痒及色素的减退或脱色的疾病有很多种，不只是外阴白斑一种，它们的表现虽有些不同，但用肉眼不易区别开来，所以当遇到外阴有病损不典型或慢性皲裂、局限性增厚、溃破等症状的患者时，必须依靠活组织病理检查确诊。
精神分裂症的病因是什么 精神分裂症是一种精神方面的疾病，青壮年发生的概率高，一般 在16～40岁间，没有正常器官的疾病出现，为一种功能性精神病。 精神分裂症大部分的患者是由于在日常的生活和工作当中受到的压力 过大，而患者没有一个良好的疏导的方式所导致。患者在出现该情况 不仅影响本人的正常社会生活，且对家庭和社会也造成很严重的影响。 精神分裂症常见的致病因素： 1、环境因素：工作环境比如经济水平低低收入人群、无职业的人群中，精神分裂症的患病率明显高于经济水平高的职业人群的患病率。还有实际的生活环境生活中的不如意不开心也会诱发该病。 2、心理因素：生活工作中的不开心不满意，导致情绪上的失控，心里长期受到压抑没有办法和没有正确的途径去发泄，如恋爱失败， 婚姻破裂，学习、工作中不愉快都会成为本病的原因。 3、遗传因素：家族中长辈或者亲属中曾经有过这样的病人，后代会出现精神分裂症的机会比正常人要高。 4、精神影响：人的心里与社会要各个方面都有着不可缺少的联系，对社会环境不适应，自己无法融入到社会中去，自己与社会环境不相
适应，精神和心情就会受到一定的影响，大脑控制着人的精神世界， 有可能促发精神分裂症。 5、身体方面：细菌感染、出现中毒情况、大脑外伤、肿瘤、身体的代谢及营养不良等均可能导致使精神分裂症，身体受到外界环境的 影响受到一定程度的伤害，心里受到打击，无法承受伤害造成的痛苦，可能会出现精神的问题。 对于精神分裂症一定要配合治疗，接受全面正确的治疗，最好的 疗法就是中医疗法加心理疗法。早发现并及时治疗并且科学合理的治疗，不要相信迷信，要去正规的医院接受合理的治疗，接受正确的治 疗按照医生的要求对症下药，配合医生和家人，给病人创造一个良好 的治疗环境，对于该病的康复和痊愈会起到意想不到的效果。
Lecture VI:Existence of Nash equilibrium Markus M.M¨o bius February26,2008 ?Osborne,chapter4 ?Gibbons,sections1.3.B 1Nash’s Existence Theorem When we introduced the notion of Nash equilibrium the idea was to come up with a solution concept which is stronger than IDSDS.Today we show that NE is not too strong in the sense that it guarantees the existence of at least one mixed Nash equilibrium in most games(for sure in all?nite games). This is reassuring because it tells that there is at least one way to play most games.1 Let’s start by stating the main theorem we will prove: Theorem1(Nash Existence)Every?nite strategic-form game has a mixed-strategy Nash equilibrium. Many game theorists therefore regard the set of NE for this reason as the lower bound for the set of reasonably solution concept.A lot of research has gone into re?ning the notion of NE in order to retain the existence result but get more precise predictions in games with multiple equilibria(such as coordination games). However,we have already discussed games which are solvable by IDSDS and hence have a unique Nash equilibrium as well(for example,the two thirds of the average game),but subjects in an experiment will not follow those equilibrium prescription.Therefore,if we want to describe and predict 1Note,that a pure Nash equilibrium is a(degenerate)mixed equilibrium,too. 1