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101.
Core biopsies of the bone marrow are indispensable in the evaluation of fever of unknown etiology in human immunodeficiency virus-positive patients. We report two patients in whom visceral leishmaniasis was diagnosed based on the typical morphology, staining characteristics, and ultrastructure of the organisms.  相似文献   
102.
A 2-year-old German Holstein bull was identified as a carrier of a mutation within the X-chromosomal ED1 gene, which encodes a TNF-related signalling molecule mainly involved in ectodermal development. The clinicopathological appearance was associated with hypotrichosis, hypodontia, and a reduced number of eccrine glands, in addition to chronic rhinotracheitis and partial squamous metaplasia. Furthermore, for the first time in an ED1-deficient animal, a complete lack of respiratory mucous glands was observed. This suggests that the ED1 gene plays a role in the development of mucous glands, the absence of which resembles a feature of X-linked anhidrotic ectodermal dysplasia (ED1) in human patients.  相似文献   
103.
The observation that v-src-induced tumors contain tumor cells of differing morphology, notably fibroblastoid or polygonal, raised the question as to whether the tumor cells are also heterogeneous with respect to expression of markers of cellular differentiation. Of the markers tested here, consistent reactivity for tumor tissue was noted only for antibody probes reactive to muscle actin (HHF35, sm-1) or to procollagen type I (SP1. D8); for any given tumor, whether induced by v-src DNA or by Rous sarcoma virus, each of these markers was found only in a subpopulation of tumor cells. The observation of marker heterogeneity in the one v-src DNA-induced tumor examined here that typed as monoclonal suggests that v-src-induced transformation is consonant with a degree of plasticity in the phenotypes of the clonal progeny of a single transformant.  相似文献   
104.
Loss of the CD5+ and CD45RAhi B cell subsets in alcoholics   总被引:1,自引:0,他引:1       下载免费PDF全文
Chronic alcoholics are frequently immunodeficient, have polyclonal hypergammaglobulinaemia, and often have autoantibodies. Recent work in other diseases has shown that functional distinctions of possible relevance to autoimmunity and immunodeficiency can be found among the B cell subsets defined by differential expression of the surface markers CD5 and CD45RA. Therefore, we have evaluated the CD5,CD45RA B cell subsets of both chronic alcoholics without evidence of active liver disease (AWLD), and alcoholics admitted for acute alcoholic liver disease (ALD). Mean B cell numbers were normal in AWLD, but significantly reduced in ALD. Analysis of B cells by three-colour flow cytometry in 20 patients and 29 controls revealed a sharp decrease in the percentage of alcoholics’ B cells which were CD5+, 37·6% versus 16·3%, P<0·00001; absolute CD5+ B cell numbers were similarly reduced (58·9 cells/μl versus 20·9; P =0·0012). In addition to the loss of CD5+ B cells, there was a reduction in the percentage of B cells which are CD5CD45RAhi, leaving many patients with a B cell profile which was predominantly CD19+CD5CD45RAlo. This subset appears phenotypically similar to the IgM-producing CD5CD45RAlo subset described by others, and may be enriched for autoantibody-producing cells. One outlier patient was an ALD with 61% of B cells which were CD5+, which also is a profile consistent with increased autoantibody production.  相似文献   
105.
There are contradictory reports regarding the effects of inhalation anesthetics on the immune system. Measurable immune responses have been studied in vitro, but little is known about the in vivo effects in the intact organism. We used an attenuated, non-neuroinvasive, nonlethal strain of the encephalitic West Nile virus, termed WN-25, which can become lethal in combination with environmental stressors, to study possible modulatory immune effects of inhalation anesthetics in mice. Both single short-term exposure and repeated exposure to halothane and nitrous oxide were studied. Exposure to 30% CO2 served as a positive control. Mortality, brain invasion, spleen weight, and antiviral antibodies served as the experimental endpoints. Halothane and nitrous oxide led to viral brain invasion, increased mortality, and suppressed immune response in a concentration- and time-dependent manner. Repeated exposures had a cumulative effect. Assessment of the stability of the viral attenuation did not demonstrate any alteration in the character of the virus, suggesting an increased access to the brain by inhalation anesthetics that led to the fatal encephalitis. These findings may be of special concern to populations at risk, such as operating room staff and patients undergoing general anesthesia in endemic areas of encephalitic virus species, in which subclinical infection may develop into an overt disease.  相似文献   
106.
A combination of the polymerase chain reaction and a novel ELISA-type DNA colourimetric assay (developed from studies with a retrovirus from man) was used in a preliminary study to detect DNA from avian infectious laryngotracheitis virus. The method is sensitive, specific and easy to perform. Since it can be readily adapted for the detection of DNA from other sources it could be useful for the identification of a variety of pathogens from other species of veterinary importance.  相似文献   
107.
Data are presented of IgM detection by a neutralization test used routinely in 1,062 patients. Antigens isolated during the period of investigation were EV4, EV7, EV11, EV18, EV21, EV24, EV33, CA9, CB2, CB4, and CB5. No difference was observed in the distribution of IgM-positive sera according to age and sex. Total antibodies are at higher titres when IgM antibodies are present. Polytypic IgM responses are not frequent (less than 10%). The frequency of the IgM-positive sera for a given serotype correlated with the frequency of isolates for the serotype except for CA9. Other than for babies under age 6 months, IgM detection is more frequent than is isolation. The susceptibility of the elderly and the frequency of IgM-positive sera among adults over age 40 years suggests possible underestimation of enterovirus infections in adults. The duration of IgM remains a major question.  相似文献   
108.
DNA cloned from the ayw subtype of hepatitis B virus   总被引:4,自引:0,他引:4  
DNA from the ayw subtype of hepatitis B virus (HBV) was ligated into the EcorI site of DNA from plasmid pBR322 and propagated in E coli chi 776. A plasmid with a 3200 base pair insert (pHBV-1) was isolated and the cloned HBV DNA was mapped with restriction endonucleases. Differences were found in restriction endonuclease cleavage sites for DNAs from HBV of subtype ayw and adr.  相似文献   
109.
Sera from 14 patients with type 2 autoimmune hepatitis (anti-LKM1 positive) were investigated for evidence of hepatitis C virus (HCV) infection. Antibodies to HCV were detected in 13 patients by both commercial and "in-house" ELISAs and also by a second generation recombinant immunoblot assay. Nine of the 13 (69%) anti-HCV positive patients were shown to be viraemic by a polymerase chain reaction-based assay for serum HCV RNA. Neither anti-HCV nor serum HCV RNA were detected in any of 6 controls with primary biliary cirrhosis or in 39 healthy blood donors. These findings strongly suggest a role for HCV in the pathogenesis of type 2 autoimmune hepatitis.  相似文献   
110.
PENA方法的建立及与ELISA IgM检测CMV的比较   总被引:1,自引:0,他引:1  
目的 介绍一种敏感、稳定、快速、简便的实验室检测CMV的方法 ,同时探讨该种新方法与ELISA检测CMV方法的优、缺点。方法 对 5 5 2例病人应用间接荧光免疫法测定细胞核中的特异病毒早期抗体 (PENA)和ELISA法测定IgM抗体。结果 PENA方法 :强阳性 88例 ,阳性率 15 4 9% ,弱阳性 2 73例 ,阳性率 5 9 4 6 % ;ELISA -IgM方法 :阳性 34例 ,阳性率6 16 %。结论 PENA方法操作简便 ,与ELISA方法相比较 ,可对CMV感染进行早期测定及诊断 ,并可区分既往感染和即时感染 ,具有敏感性和稳定性 ,是测定小儿CMV感染的一种较好的方法  相似文献   
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