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121.
The present paper reports 11 cases of light chain disease (LCD) sequently found in several citles over Fujian province, Immunological classification of this group of LCD ww as follows: six of me cases belonged to type λ, four of them were type κ, and another one was a double LCD. We found that LCD was common in Fujlan only next to multiple myeloma (MM) of IgG class and accounted for 20% of the total 55 MM cases found in recent yean.It to well known that In matt patients of LCD M protein or Bence Jones proteinemia (BJPemia) to not detectable by conventional electro-phoresis. Our studies show that by making serum protein along with urinary BJP electrophoresis on the same one gel plate the sltuation can be greatly Improved It not only favour* the recognition of smail and faint band or bands of free light chain in serum, but also provides a repid and sensitive way, i. e. , immunofixation, to directly detect urinary light chain on the gel plate Immediately after electrophresis has been run. 相似文献
122.
目的:建立一种快速鉴定临床常见真菌菌种的方法。方法:选取真菌核糖体RNA的ITS区为靶基因,设计通用引物和种特异性探针,将3个属的6种临床常见真菌(白色念珠茵、热带念珠茵、光滑念珠茵、新型隐球菌、烟曲霉和黄曲霉)的种特异性探针加尾后固定于硝酸纤维素膜上;用标记生物素的真菌通用引物扩增11种医学真菌DNA,产物与固定在膜上的探针杂交。结果:通用引物可以扩增所试11种医学重要真菌的DNA,扩增片段长度约为560bp。6种真菌扩增产物只与其对应的探针杂交。结论:此方法快速、简便、特异,适合常规实验室开展。 相似文献
123.
听骨链多层螺旋CT曲面重建及临床应用 总被引:1,自引:0,他引:1
目的研究听骨链的CT曲面重建(CPR)方法,评估其临床应用价值。方法165耳(122例)行颞骨轴位高分辨率CT检查,对听骨链行CPR。50例(80耳)为正常听骨链,72例(85耳)为病变组。主要扫描参数:准直0.5mm,螺距0.875,重建间隔0.2~0.3mm,重建矩阵1024×1024。结果(1)正常听骨链组:1幅图像上清晰显示3个听骨及其关节。(2)临床应用:39例颞骨外伤中,听骨链异常的18例;锤砧关节半脱位及脱位各5例,砧镫关节半脱位及脱位分别为5例及6例,锤骨柄骨折1例。16例外耳发育不良中,骨性外耳道闭锁13例,膜性3例。骨性外耳道闭锁最常见的伴随听骨畸形是锤骨柄发育不全(10例),中耳腔变窄、听骨缺如3例,锤砧融合伴砧骨长突缺如1例。不伴随先天性外耳发育不良的听骨畸形2例,1例为双耳砧骨长突缺如,另1例为砧骨长突发育不全伴砧镫关节不连。慢性中耳乳突炎15例,6例合并胆脂瘤者听骨均有不同程度的破坏,鼓室硬化症1例。结论听骨链的多层螺旋CT曲面重建是诊断传导性耳聋的有效方法。 相似文献
124.
目的 为了降低异基因造血干细胞移植(allo-HSCT)后巨细胞病毒(CMV)感染的相关死亡率,寻求一种更快捷、更特异的诊断CMV感染的分子生物学方法。方法 2001年4月至2003年4月,从79例接受异基因造血干细胞移植的患者中采集了135份外周血标本。采用巢式聚合酶链反应(nested-PCR)方法检测患者外周血中CMVgB DNA,阳性标本做酶切分型,部分行序列测定。结果CMVgB DNA检测中有42例患者(53.9%)的66份标本(48.9%)阳性;对其中阳性患者的45份标本进行了酶切分型,结果 CMV gB1型21例(46.7%),CMV gB2型14例(31.1%),CMV gB3型7例(15.6%),CMV gB4型3例(6.7%)。先后有2种型别的CMV感染者有3例(3.8%)。经分析,CMV gB阳性和CMV gB阴性患者GVHD的发生率分别为81.0%和32.4%(P<0.01);CMV gB1、gB2、gB3以及gB4型Ⅱ~Ⅳ度急性GVHD及慢性GVHD的发生率分别为:81.0%、50.0%、42.9%和0。结论 Nested-PCR方法可快捷特异地检测CMV感染。CMVgB1、2型中,重度急性GVHD和慢性GVHD发生率较高。CMV gB基因分型检测可有效地指导临床抗病毒治疗,且对移植后患者的临床转归有一定的预测价值。 相似文献
125.
目的检测成牙本质细胞中上游刺激因子1(upstream stimulatory factor 1,USF1)对骨桥素表达的影响。方法培养成牙本质细胞MDPC-23,稳定转染PCMV-USF1和酸性-USF(A-USF)质粒,提取总RNA,半定量反转录聚合酶链反应检测骨桥素的表达水平,并对结果进行统计学分析。结果筛选出稳定转染USF1和A-USF的抗性克隆,USF1、A-USF转染组和对照组骨桥素相对灰度比值分别为:60.33%±4.51%、229.33%±7.09%、110.00%±15.62%,转染组与对照组差异有统计学意义(P〈0.01)。结论USF1可调控成牙本质细胞骨桥素mRNA转录,该作用被A-USF部分阻断。 相似文献
126.
127.
浙江省在鼠中检测到埃立克体及无形体DNA片段并测序分析 总被引:1,自引:0,他引:1
目的:了解鼠中自然感染埃立克体及无形体的状况。方法:用巢式PCR扩增鼠中埃立克体属及嗜粒细胞无形体属16S rDNA的5′末端片段,对阳性产物克隆后测序。结果:在浙江省金华市金东区捕到鼠128只。在黄毛鼠中检到阳性4份,阳性率为3.125%,并对其进行克隆后测序。与Genbank上比对分析,三份与牛埃立克体相同基因区最为接近,属无形体科,无形体属。一份与反刍动物埃立克体相同基因区最为接近,属无形体科,埃立克体属。均为国内首次报道。结论:初步认为浙江省存在埃立克体及无形体病原。黄毛鼠可能为埃立克体及无形体宿主,尚需进一步调查。 相似文献
128.
Pierre Boudinot Dominique Rueff-Juy Anne-Marie Drapier Pierre-Andr Cazenave Pierre Sanchez 《European journal of immunology》1995,25(9):2499-2505
The diversity of the B cell repertoire of Cx knockout mice is limited by the expression of four λ light chain types. Among the spleen B cells, λ1 is expressed by the majority (58%) of cells, and λ3 by the minority (8%), while λ2(V2) and λ2(Vx) are expressed in intermediate quantities (18% and 16%, respectively). To assess the influence of mechanistic pressures on the λ subtype distribution, the proportions of the different λ rearrangements were determined in various B cell subpopulations divided on the basis of the λ subtype expressed, and the VλJλ junction sequences were studied at different steps of B cell differentiation (pre-B, immature and mature B cells). The data show that (1) the ratio of productive/non-productive VJ junctions is determined by the nature of the λ segments that are rearranged as can be observed in the pre-B cells, (2) V1-J1 non-productive rearrangements are often found in the λ1-negative B cells in the periphery, and (3) V1J3 junctions are often non-productive regardless of the nature of the cells analyzed. Our results, therefore, suggest that a strong probability of initiating a V1-J1 rearrangement and a weak probability of giving a productive V1J3 junction are responsible for the λ1 dominance and the λ3 under-expression, respectively. The intermediate proportion of λ2(V2) subtype is most likely due to a probability of obtaining a productive joint that is better than that for V1J3 and a probability of initiating a rearrangement that is lower than that for V1J1. However, the λ2(Vx) cell proportion cannot be determined only by these parameters. 相似文献
129.
Antonella d’Arminio Monforte Paola Cinque Luca Vago Aleandro Rocca Antonella Castagna Cristina Gervasoni Maria Rosa Terreni Roberto Novati Andrea Gori Adriano Lazzarin Mauro Moroni 《Journal of neurology》1996,244(1):35-39
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination
to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents.
CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr
virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR
was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one
autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven
and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive)
were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma
therapy affected the sensitivity of both histological and CSF-PCR methods.
Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996 相似文献
130.
PCR诊断早期肾结核的探讨 总被引:5,自引:1,他引:4
探讨聚合酶链反应(PCR)诊断早期肾结核的实用价值,应用PCR技术快速检测尿中结核杆菌DNA诊断不明原因的无症状性镜下血尿者23例,结果9例阳性,经抗结核治疗,9例镜下血尿全部消失,认为PCR技术诊断早期肾结核具有速度快、特异性高,灵敏度大的优点,可列为疑诊早期肾结核检测常规。 相似文献