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71.
Analysis of retrospective data, obtained on 216 patients from 27 centers transplanted across some form of positive lymphocyte cross-match in a noncurrent serum, revealed that actuarial 1-yr graft survival was 69% in first transplants and 53% in recipients of second or subsequent transplants. Graft outcome did not correlate with peak antibody levels, change in antibody from peak to current, remoteness in time of the most recent positive serum, the number or timing of sera cross-matched, the technique or target cell cross-matched, or the degree of positivity of the most recent positive serum. Although a concurrent control population was not available, these results support the concept that acceptable graft survival can be achieved despite a positive cross-match with noncurrent sera.  相似文献   
72.
Oesophageal squamous cell carcinoma with lymphoid stroma   总被引:4,自引:0,他引:4  
Summary We treated a 70-year-old Japanese man with squamous cell carcinoma of the oesophagus with evidence of lymphoid stroma. The tumour consisted of a main lesion invading the muscular layer of the oesophagus, in association with wide areas of carcinoma in situ. The tumour stroma of the lesion was nondesmoplastic and was uniformly infiltrated mainly by abundant lymphocytes and plasma cells. Immunohistochemically, the lymphocytes consisted of a large number of T lymphocytes and a small number of B lymphocytes. S-100 protein positive cells were marked in the tumour cell nests and necrotic change of tumour cells was frequent. Abundant infiltration of lymphocytes and plasma cells was also wide-spread beneath the carcinoma in situ, together with the lymphoid follicles. Carcinoma with lymphoid stroma can occur not only in the breast, uterine cervix, nasopharynx and stomach but also in the oesophagus.  相似文献   
73.
The availability of tetrameric complexes of HLA class I molecules folded with immunodominant peptides makes it possible to utilize flow cytometry for rapid and highly specific visualization of virus specific CD8+ T cells. An alternate technique is to incubate whole blood with specific antigens and to subsequently detect and characterize responding T cells (e.g. by performing intracellular staining of interferon-gamma). By using an HLA-A2 tetramer construct folded with the same immunodominant CMV-peptide as that used for peptide pulsing, we monitored both the presence and functional capacity of CMV-specific CD8+ T cells. In addition T cell activation was assayed by determination of CD38 and CD69 expression. Twelve organ transplant patients and 31 healthy blood donors with latent CMV infection were investigated using CMV pp65 tetramer staining and intracellular staining of interferon-gamma after CMV pp65 peptide pulsing or CMV lysate pulsing. CMV-specific T cells were detected in similar absolute numbers as well as frequencies of T cells in the two groups investigated. However, the CMV-specific CD8+ T cells in immunosuppressed individuals showed a decreased functional response to the CMV-peptide, as evidenced by reduced interferon-gamma production when compared to healthy blood donors (19%; 42%, P < 0.005). In addition, CD38 expression was markedly higher in immunosuppressed patients compared to healthy blood donors (24%; 6%, P < 0.005). In a case report we demonstrate that reactivation of CMV can occur in an immunosuppressed patient with high number of CMV-specific T cells, but without functional capacity. Hence, these findings reflect impaired activation of cytotoxic T cells controlling latent CMV infection in immunosuppressed patients.  相似文献   
74.
Transplantation Centers using human cytomegalovirus (HCMV) antigenemia-based preemptive therapy will need to replace in the near future the antigenemia assay with a more standardized and automatable assay, such as a molecular assay quantifying HCMV DNA in blood (DNAemia). Thus, in view of replacing antigenemia with clinically safe cutoff values, DNAemia levels corresponding to antigenemia cutoffs guiding HCMV preemptive therapy were determined retrospectively in solid organ and hematopoietic stem cell transplant recipients (HSCTR) using an "in-house" quantitative PCR (QPCR) method. Since preemptive therapy had prevented appearance of HCMV disease in all patients tested, DNA cutoffs determined retrospectively had to be considered as safe clinically as antigenemia cutoffs used prospectively. However, in solid organ transplant recipients (SOTR), initiating preemptive therapy upon an antigenemia cutoff of 100 pp65-positive leukocytes, a DNAemia cutoff of 300,000 copies/ml blood had positive and negative predictive values of >90%, indicating that a DNAemia cutoff could achieve, in terms of prevention of HCMV disease, the same clinical results as the antigenemia cutoff. In HSCTR, initiating preemptive therapy upon first antigenemia positivity, a DNAemia cutoff of 10,000 copies/ml blood had a positive predictive value of >90%, indicating that the great majority of patients treated under the antigenemia guidance would have been treated also using this DNA cutoff. On the other hand, the negative predictive value of 28.6% indicated that two out of three HSCTR had been treated under the antigenemia guidance having the same levels of viral DNA as the untreated patients. The data suggest that a quantitative cutoff could be adopted as a guiding criterion for preemptive therapy also in HSCTR. Regression analysis allowed to determine the DNAemia (corresponding to QPCR) cutoff values for two commercial assays tested both in solid organ and HSCTR. Retrospective DNAemia cutoff values will be verified for safety in prospective trials.  相似文献   
75.
社会技能训练对慢性精神分裂症疗效的对照研究   总被引:12,自引:0,他引:12  
目的:探讨社会技能训练对慢性精神分裂症阳性症状、阴性症状及认知功能的疗效.方法:将100例慢性精神分裂症患者随机分为训练组(50例)和对照组(50例).对训练组按照Liberman RP编写的<社会独立生活技能>训练程式进行训练,共12周.用BPRS、SANS、SDSI和WCST进行评定.结果:(1)训练组BPRS在总分和焦虑抑郁及缺乏活力因子分低于对照组,差异有显著性(P<0.05).(2)接受12周社交技能训练后,训练组的SANS量表全部五个因子和总分低于对照组,均有显著差异(P<0.05).(3)训练组和对照组在WCST的5个指标,差异有显著性(P<0.05).(4)SDSI评定结果表明,训练后明显降低,差异有显著性(P<0.05).结论:社会技能训练能够改善慢性精神分裂症的阳性症状、阴性症状及认知功能.  相似文献   
76.
Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool.  相似文献   
77.
A method for enzyme-based in situ hybridisation of Streptococcus suis was developed. It enables the light microscopic localization of bacterial ribosomal RNA (rRNA) in formalin-fixed paraffin-embedded tissues. A unique sequence in the 16S rRNA of S. suis was targeted. Different pretreatment protocols were applied to facilitate probe penetration and multiple detection systems were tested. The results were compared to those obtained by immunohistochemistry. Pretreatment was necessary to obtain a signal by in situ hybridisation. The use of proteinase-K pretreatment was optimal regarding sensitivity and preservation of tissue morphology. A strong specific in situ hybridisation signal was achieved in tissue sections containing S. suis in microcolonies and the microanatomy of the surrounding tissue was easily assessed. However, the signal distribution differed from that found immunohistochemically and low-grade infection could not be detected by in situ hybridisation. These findings were interpreted as reflecting the physiological state of the bacteria. Thus, this method could prove useful in future studies of the infection pathogenesis.  相似文献   
78.
丹参和黄芪治疗气虚血瘀型心力衰竭的作用   总被引:2,自引:0,他引:2  
本文报道91例气虚血瘀型心力衰竭(心衰)病人选用丹参和黄芪治疗作用。16例作气囊漂浮导管监测,发现黄芪明显增加心排出量、每搏量及心脏指数,而丹参无此作用,提示黄芪有正性肌力作用;30例给黄芪加党参,治疗后心功能分级及某些异常的血液流变学指标均有改善;44例先丹参,继之丹参加黄芪,治疗后心功能分级有明显改善,且能改善异常的血液流变学指标,明显抑制血小板聚集功能。提示丹参具有活血化瘀改善血液流变学及抑制血小板的聚集性,黄芪有补气强心改善心功能的作用。  相似文献   
79.
We have studied the haemodynamic effects of the application of the medical anti-shock trouser (MAST) in 10 healthy subjects in the semi-upright position in order to simulate mild hypovolaemia. Left ventricular end diastolic dimension (EDD) was measured by M-mode echocardiography and cardiac output (CO) by the Doppler ultrasound technique. Forearm blood flow (FBF) was measured by plethysmography and blood pressure (BP) by the standard cuff technique. Systematic increases in MAST pressure of up to 80 mm Hg were applied. EDD increased to a maximum of 9.3% (p0.01) which was associated with a maximum increase in CO of 31.7% (p0.05). FBF increased by a maximum of 54.2% (p0.001) whilst BP increased by a maximum of 12% (p0.001). These results demonstrate that the application of the MAST is an effective means of transferring blood to the central circulation by compression of the capacitance vessels resulting in significant increases in cardiac output and tissue perfusion. At high pressures there was evidence of compression of resistance vessels, which may be useful in reducing blood loss. The ease and rapidity with which his suit can be applied suggests that it may be useful in the short term treatment of hypovolaemia.  相似文献   
80.
目的:探讨家庭社会经济地位与青少年主观幸福感的关系及领悟社会支持和积极心理资本的中介作用。方法:采用家庭社会经济地位问卷、幸福感指数量表、领悟社会支持量表和积极心理资本问卷调查了932名青少年。结果:(1)家庭社会经济地位、领悟社会支持、积极心理资本和主观幸福感两两之间相关显著;(2)家庭社会经济地位对主观幸福感的直接效应不显著,但领悟社会支持、积极心理资本在家庭社会经济地位与主观幸福感之间的三条中介路径均显著。结论:为提升低家庭社会经济地位青少年主观幸福感,改善其领悟社会支持和积极心理资本水平是可实现的有效路径。  相似文献   
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