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21.
系统性红斑狼疮患者淋巴细胞亚群早期凋亡的初步研究   总被引:8,自引:3,他引:5  
目的:检测系统性红斑狼疮(SLE)患者外周血单个核细胞(PBMC)中不同细胞亚群发生凋亡的情况,并初步分析其在SLE发病机制中的意义。方法:取28例SLE患者和性别年龄与之相匹配的20个正常对照者。采用淋巴细胞亚群标志、Annexin-V及碘化丙啶三色荧光标记、流式细胞术检测细胞的早期凋亡。结果:SLE患者体内CD3^ T细胞、CD4^ T细胞和CD8^ T细胞的凋亡百分率均显著高于正常对照组(P<0.05)。同时,SLE患者T淋巴细胞的死亡百分率也高于正常人。经激素治疗一定时间后,这些细胞亚群的凋亡率会进一步升高(P<0.01),但CD4/CD8比值恢复至接近正常人。SLE患考体内CDl9^ B淋巴细胞的凋亡或死亡百分率和正常对照组相比均无明显差别,激素治疗对B细胞凋亡和死亡的影响亦不显著。结论:在SLE患者体内主要是T淋巴细胞凋亡增加,但SLE患者淋巴细胞数目减少不仅仅是因为细胞凋亡所致,死亡细胞数目明显升高也是其中一个重要原因。激素治疗可诱导SLE患者T淋巴细胞进一步发生凋亡,并使T细胞亚群比例有所改善。  相似文献   
22.
In a retrospective study the prognostic significance of nuclear DNA content was investigated, as measured by flow cytometry, of the tumor specimens from 212 women with nonpretreated FIGO stage IB and II cervical cancer. One-hundred and thirty cases (62%) were found to be diploid, whereas 82 (38%) were aneuploid. Univariate analysis of the follow-up data showed an increased relative risk (RR) for recurrence free survival (RFS) for stage II tumors (RR = 1.87, 95% CI: 1.13–3.10, P = 0.015) and for age (RR = 1.52, 95% CI: 0.66–3.52 and RR = 2.35, 95% CI: 1.19–4.65, P = 0.032). Ploidy showed a relative risk of 1.33 (95% CI: 0.83–2.13, NS). In addition, univariate analysis of overall survival (OS) revealed similar results. For the subgroup of patients with primary surgery ( n = 151), positive pelvic nodes (RR = 5.38, 95% CI: 2.70–10.71, P = 0.0001) and parametrial extension (RR = 2.53, 95% CI: 1.24–5.17, P = 0.011) were significant factors for OS after univariate analysis, the estimated effects on RFS were slightly smaller. Multivariate analysis of RFS for the whole study population showed age, histologic grade and stage with a slightly increased risk, but no effect was significant. Ploidy with an RR of 0.97 (95% CI: 0.58–1.62) seems to have no influence on prognosis. For the subgroup with primary surgery, ploidy again failed statistical significance with an RR of 1.20 (95% CI: 0.58–2.49). Our results suggest that abnormalities of the nuclear DNA content in this homogeneous group of patients are associated with clinical and morphological prognosticators, however, ploidy is not an independent prognostic factor for RFS, or for the whole study population or for the subgroup with primary surgery.  相似文献   
23.
The basilar artery is the only large artery in which two flows merge, and this is reflected in the flow downstream. We report quantitative flow — velocity measurements with a phase-based MR technique, i.e. the Fourier velocity encoding method, in the basilar artery of a volunteer. To our knowledge, this has not previously been performed successfully. A comparison is made with the results of flow velocity measurements in the basilar artery with transcranial Doppler ultrasonography; the techniques agreed very well. Although Doppler ultrasonography is still most widely used, no information on the flow rate and the flow velocity distribution in the basilar artery can be provided. MR flow measurement techniques appear promising when detailed information on the flow velocity distribution and flow rate is needed.  相似文献   
24.
Recently generated anti-Xenopus T cell monoclonal antibodies (mAbs) to the 120 kDA XTLA-1 determinant and against the putative CD5 and CD8 homologues, together with anti-IgM and anti-MHC class II mAbs, are used in dual colour flow cytometric experiments to characterize cell surface antigenic expression on lymphocytes in thymus and spleen of Xenopus laevis during larval and early adult life and also in metamorphosis-inhibited animals. Histological confirmation of T cell emergence early in larval ontogeny is supplied by cryostat sections stained for CD8. Five-day thymectomy i.e. prior to T-lineage cell differentiation in the thymus, abolishes T cell marker expression in the spleen for up to 1 year. Moreover, late larval (20 days) or early adult (3 months) thymectomy (i.e. removal after peripheralization of T cells has occurred) also leads to severe depletion of mAb-defined T cells in the spleen.  相似文献   
25.
In order to assess the suitability of DNA flow cytometry of fine-needle aspirates for quantiftring spermatogenesis, the results from DNA flow cytometry were compared to histological evaluation of testicular biopsies taken concomitantly from 171 previously maldescended testes. In 137 of 171 cases, sufficient material for flow cytometric as well as histological evaluation was obtained.
Histological analysis of surgical biopsy specimens revealed spermatogenesis including the spermatid stage in 117 of the 137 gonads. In six of the 117 gonads no haploid cells were found using flow cytometry. On the other hand, surgical biopsies failed to reveal spermatogenesis in five cases in which the corresponding aspirates contained haploid cells. Both methods therefore seem equally sensitive in detection of spermatogenesis.
Other types of histological patterns also corresponded to distinct DNA histograms.
Thus, in 11 of 12 cases with Sertoli-cell-only pattern in all tubules, at least 95% of the cells had a diploid DNA content. Furthermore, predominance of tubules with maturation arrest at the primary spermatocyte level corresponded to an increased proportion of tetraploid cells.
When compared to surgical biopsy, DNA flow cytometry of testiclar fine-needle aspirates is a more objective, easy and rapid method, which is more convenient for the patient. This study has indicatedthat DNA flow cytometry is a suitable method of quantitative assessment of spermatogenesis. One of the first target groups might be men with azoospermia. In such men, DNA flow cytometric analysis of fine-needle aspirates and surgical biopsy are apparently of equal sensitivity in detecting gonads with spermatogenesis. We conclude that DNA flow cytometry may become an alternative method for the quantification of spermatogenesis.  相似文献   
26.
The authors describe their preliminary experience with the use of superparamagnetic magnetic resonance (MR) imaging contrast media for suppression of signal from flowing blood. The goal of this work was to determine if a superparamagnetic contrast agent could successfully eliminate blood signal during cardiac-gated MR imaging, thereby eliminating or reducing flow artifacts associated with the complex and variable hemodynamics within the heart chambers. Imaging and data analysis were performed in 17 dogs subjected to experimental myocardial infarction as part of a parallel project. Six doses (0.2, 1, 2, 3.5, 4, 5, and 10 mg/kg) of AMI-25, an experimental contrast agent, were used in the study. Spin-echo imaging was performed immediately before and every 5 minutes (for an average of 25 minutes) after bolus injection of the contrast agent. Variations in the image signal-to-noise ratio relative to a baseline (before injection of contrast agent) image were assessed as a function of dose and time. Preliminary results suggest that a considerable reduction in blood flow artifacts and, hence, increases in image signal-tonoise ratio can be achieved at doses greater than or equal to 3.5 mg/kg, for approximately 20 minutes after injection. Doses equal to or less than 2 mg/kg and images obtained more than 20 minutes after injection (regardless of dose) did not reliably show hemodynamic artifact suppression.  相似文献   
27.
本文对上消化道肿瘤高发区经初筛的120例高危人群粘膜组织做了流式细胞DNA含量、内窥镜和组织病理学检查的对比研究。其结果显示的肿瘤阳性检出率分别为27.5%、6.7%和14.0%。对内窥镜诊断为不同胃疾病患者的流式细胞术分析发现,流式细胞术阳性检出率,胃癌组为75.0%,萎缩性胃炎组为28.3%,浅表性胃炎组为7.1%,正常粘膜组为0%。DI值均值,炎症组(萎缩性胃炎和浅表性胃炎)患者与正常对照组接近,而癌组则明显升高。增殖指数和S期细胞比例,从正常对照→浅表性胃炎→萎缩性胃炎→胃癌组,呈递增变化,而且各组间有显著差异。  相似文献   
28.
目的:探讨己酮可可碱(PTX)对大鼠睾丸扭转复位后生精功能的保护作用。方法:雄性SD大鼠24只,随机分成3组,每组8只,建立睾丸扭转动物模型。第Ⅰ组为假手术组(扭转720°后立即复位),第Ⅱ、Ⅲ组扭转720°2 h,于复位前15 m in分别静脉注射生理盐水和PTX,术后24 h留取手术侧睾丸。应用流式细胞术(FCM)检测各组生精细胞凋亡和各级生精细胞计数,采用硫代巴比妥酸法测定丙二醛(MDA)含量,化学比色法测定组织内总抗氧化能力(T-AOC)。结果:第Ⅲ组应用PTX后与第Ⅱ组相比,生精细胞凋亡明显减少(399.50±33.31vs1221.75±132.48,P<0.01),单倍体和四倍体细胞群计数显著增多(5554.13±441.28vs4102.35±206.98;1906.00±200.72vs1711.63±144.55,P均<0.01;),T-AOC明显回升(32.52±2.86vs22.76±3.73,P<0.01),MDA含量下降(1.78±0.20vs3.98±0.36,P<0.01),其差异均有显著性(P<0.01)。结论:己酮可可碱对睾丸扭转复位后的生精功能具有明显的保护作用。  相似文献   
29.
Summary We studied paired cerebrospinal fluid (CSF) and peripheral blood (PB) samples from 18 inactive multiple sclerosis (MS) patients and 10 with non-inflammatory neurological diseases. By means of a dual-colour cytofluorimetric micromethod we were able to count 1500 cells on average in each CSF sample. We found a significant reduction of CD45RA+ and CD4+CD45RA+ cells in the CSF of MS patients. Similarly, CD45RA+ and CD4+CD45RA+ CSF/PB ratios were lower compared with controls. The reduction of suppressor-inducer T-cells did not correlate with CD8+ cell levels in the CSF. The CD4+ subset ratio (CD4+CD45RA–/CD4+CD45RA+) was significantly increased in the CSF of MS patients. Our data suggest that the reduction of CD4+CD45RA+ cells in the PB is not due to a segregation of such cells in the CSF. Conversely, CSF changes reflect changes in the PB similar to these found for other T-cell subsets.  相似文献   
30.
宫颈癌细胞增殖和DNA倍体与放射敏感性的关系   总被引:2,自引:0,他引:2  
为研究宫颈癌细胞增殖参数 S期比例 (SPF)、增殖指数 (PI)和 DNA倍体与宫颈癌放射敏感性的关系 ,探讨它们在预测宫颈癌放射敏感性中的价值。对 4 7例宫颈癌患者放疗前行宫颈癌组织取材 ,进行流式细胞术分析 ,在放疗过程中每周测量 1次宫颈局部瘤床的大小 ,计算肿瘤消退 1/ 2所需照射剂量 (D0 .5 ) ,研究 SPF、PI和 DNA倍体与D0 .5之间的关系。结果显示 :SPF与 D0 .5呈正相关 (r=0 .6 0 4 ,P<0 .0 1) ,PI与 D0 .5无明显关系 ,DNA倍体对 D0 .5的影响有显著性意义 (P<0 .0 5 )。提示 :宫颈癌细胞放疗前 SPF和 DNA倍体与放射敏感性有关 ,该两项指标有可能成为宫颈癌放射敏感性的预测指标  相似文献   
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