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91.
目的 观察原发性食管癌中胸苷磷酸化酶 (thymidinephosphorylase,TP)的表达情况 ,探讨肿瘤组织中胸苷磷酸化酶表达、肿瘤微血管密度 (microvesseldensity ,MVD)和临床病理特征之间的关系 ,分析TP表达和肿瘤MVD的预后意义。方法 应用单克隆抗体对 6 5例食管癌标本进行免疫组化染色 ,测定TP表达及MVD。结果 TP在食管癌中的表达 (4 5 / 6 5 ,6 9.2 % )明显 (P <0 .0 0 1)高于正常食管粘膜 (4 / 2 4 ,16 .7% )。食管癌的MVD(4 5 .0 9± 8.76 )与正常食管粘膜的MVD(2 7.4 8± 8.4 4 )的差别显著 (P <0 .0 0 1)。食管癌TP阳性的MVD的均值是 (4 6 .5 3± 7.18) ,TP阴性的MVD的均值是 (4 1.85± 11.0 8) ,前者明显 (P =0 .0 4 6 ) 高于后者。食管癌的TP表达与临床病理特征无相关性 ,MVD却与肿瘤的浸润深度(P =0 .0 35 ) 及分期(P =0 .0 18) 有关 ,而且只有MVD才是食管癌的一个预后指标(P <0 .0 0 1)。结论 食管癌的TP表达与MVD密切相关。TP表达与食管癌的临床病理特征无关。MVD与肿瘤的浸润发展有关 ,同时只有MVD才是食管癌的一个预后指标 相似文献
92.
We have investigated the ontogeny of MHC class I, class II, CD45, and macrophage antigens in wholemounts of normal human fetal retina at 10–25 weeks gestation (WG) using monoclonal antibodies and immunogold histochemistry. MHC class I antigens were expressed on retinal vascular endothelial cells and provided a useful marker of vessel organization from 14–25 WG. Microglial cells expressed immunoreactivity to MHC class I, class II, and CD45 antigens from 10 WG (pre-vascularization) and macrophage S22 (Mac S22) antigen from 14 WG (post-vascularization), although none of the antigens tested were detected on neuronal or macroglial elements. Microglia expressing MHC, CD45, and macrophage antigens occurred in both ramified and rounded forms with no close correlation being observed between morphology and antigenicity. The numbers of immunoreactive cells labeled with each of the four markers increased steadily throughout gestation in all specimens studied. Equivalent numbers of microglia expressed MHC class I, class II, and CD45 antigens in retinae at similar gestational ages; however, our data indicate that microglia expressing Mac S22 antigen comprise approximately 40% or less of the population of MHC and CD45-immunoreactive cells during development. Topographical analyses suggest that MHC class I, class II, and CD45-positive microglia enter the retina from both the peripheral retinal margin and the optic disc from at least 10 WG; Mac S22-positive cells appear in association with the development of the retinal vasculature and enter the retina via the optic disc after 14 WG. © 1995 Wiley-Liss, Inc. 相似文献
93.
G. J. Wiener MD T. M. Morgan PhD J. B. Copper PA W.C. Wu MB BS D. O. Castell MD J. W. Sinclair PA Dr. J. E. Richter MD 《Digestive diseases and sciences》1988,33(9):1127-1133
If 24-hour esophageal pH monitoring is to be a useful diagnostic tool, it must reliably discriminate gastroesophageal reflux patients despite daily variations in distal esophageal acid exposure. To address this issue, we studied 53 subjects (14 healthy normals, 14 esophagitis patients, and 25 patients with atypical symptoms) with two ambulatory pH tests performed within 10 days of each other. Intrasubject reproducibility of 12 pH parameters to discriminate the presence of abnormal acid reflux was determined. As a group, the parameters of percent time with pH<4 (total, upright, recumbent) were most reproducible (80%). Therefore, a subject was defined as having gastroesophageal reflux disease if at least one of these three values were abnormal. Intrasubject reproducibility for the diagnosis of reflux disease was 89% for the entire sample. Among subsets, the reproducibility was 93% for the normals and esophagitis patients and 84% for the atypical symptom patients. Total percent time with pH<4 was the single most discriminate pH parameter (85%) and nearly equaled that of the three combined parameters (89%). The intrasubject variability of this parameter was determined by the mean ±2sd of the relative differences between the two test results for all 53 subjects. Total percent time with pH<4 may vary between tests by a factor of 3.2-fold or less (218% higher to 69% lower). We conclude: (1) ambulatory 24-hr esophageal monitoring is a reproducible test for the diagnosis of gastroesophageal reflux disease; and (2) the large intrastudy variability in 24-hr total acid exposure may limit this test's usefulness as a measurement of therapeutic improvement.Supported, in part, by Public Health Services Grant AM 34200-01A1 from NIADDIK. 相似文献
94.
CD44作为细胞粘附分子的一种特殊类型,广泛分布于细胞表面,通过介导细胞与细胞、细胞与基质粘附及信号转导等作用,参与组织发育、炎症反应、创伤修复等多种生理病理过程。近年来研究发现,CD44参与了某些眼部疾病的发生发展,深入探讨CD44与眼部疾病的关系,对于阐明某些眼部疾病的发病机制以及指导治疗具有重要意义。 相似文献
95.
Relationship between expression of CD40-CD40 ligand system and serum cholesterol levels in patients with hypercholesterolemia 总被引:2,自引:0,他引:2
Hypercholesterolemia is associated with the pathogenesis of atherosclerosis. Enhanced levels of thrombin, fibrinogen and factor Ⅶc directly correlate with cholesterol levels.1 Activated platelets adhere to the intact endothelium and induce inflammatory responses in the endothelium, which substantially contribute to the early phase of atherosclerosis. Emerging lines of evidence support the role of CD40-CD40L interactions in atherosclerosis, thrombosis and inflammation.2 In atherosclerosis, inhibition of the CD40-CD40L interaction in LDL receptors or ApoE-deficient mice prevents the initiation of atherosclerosis and the evolvement of established atherosclerotic lesions to more advanced lesions. 相似文献
96.
基于非标准协议的短距离无线通信,具有成本低、易开发、低功耗的优点,非常适用于小范围内的数据传输。提出一种基于非标准无线通信芯片nRF24L01的个人健康监护系统设计方案,并将其与现有的、基于标准协议无线通信的个人健康监护系统进行比较。结果表明:基于非标准协议无线通信的个人健康监护系统具有效率高、功耗低、通信性能好的特点。 相似文献
97.
Peripheral blood CD3 and CD4 T-lymphocyte reduction correlates with severity of liver cirrhosis 总被引:2,自引:0,他引:2
L. Lombardo A. Capaldi G. Poccardi P. Vineis 《International Journal of Clinical & Laboratory Research》1995,25(3):153-156
Summary Immunological disturbances with impairment of immune function and a higher incidence of lymphoproliferative disorders and
other malignancies have been described in liver cirrhosis patients. To investigate the pathogenetic mechanism(s) involved
in such associated we looked for a possible imbalance in peripheral blood T-lymphocyte subpopulations in patients with liver
cirrhosis of differing severity. Immunophenotyping and counts of peripheral blood T-lymphocyte subpopulations were carried
out using monoclonal antibodies conjugated with different fluorochromes in 31 consecutive cirrhotic patients and 23 matched
healthy volunteers. Univariate and multivariate analyses of lymphocyte phenotype counts were performed and odds ratios were
computed. Statistically significant associations, according to both univariate and multivariate analyses, were found between
case/control status and mean CD3 and CD4 T-lymphocyte counts (P<0.0001). A strong correlation was found between the Pugh’s index and CD3 and CD4 lymphocyte counts, with a clear reduction
of these phenotypes with increasing liver cirrhosis. Median CD3 and CD4 values were 2,283 and 1,329/μl respectively among
controls and 896, 801, and 492/μl and 515, 514, and 307/μl, respectively in categories A, B, and C of Pugh’s classification.
Very high odds ratios were found using the median values of CD3 and CD4 as a threshold. There was a statistically significant
decrease for each of the T-cell phenotypes studied (CD2, CD3, CD4, CD8, CD16, CD19, CD20, CD56, CD57) between patients and
controls (P<0.0001). The progressive and severity-related decrease in mean peripheral blood CD3 and CD4 counts in liver cirrhosis suggests
a progressive impairment of protective immune function and may be a factor facilitating malignancy in cirrhotic patients. 相似文献
98.
Impact of Ingested Liquids on 24-Hour Ambulatory pH Tests 总被引:1,自引:0,他引:1
J. Patrick Shoenut Donald Duerksen Clifford S. Yaffe 《Digestive diseases and sciences》1998,43(4):834-839
A prospective investigation of the impact ofingested liquids on 24-hr pH test scores was conducted.Eighty-two patients contributed 142 samples. The liquidsused were coffee/tea (N = 35), water (N = 32), fruit juice (N = 29), cola (N = 34), and beer (N =12). The pH of cola, juice, and beer are approximately3.0. The parameters studied included: total test time,total drink time, total minutes of pH < 4.0 during drink, minutes of pH < 4.0 10 min beforedrink, and minutes of pH < 4.0 10 min followingdrink. Analysis was performed using one-way ANOVA andrepeated measures. Age of patients, total test time, and total time pH < 4.0 were notsignificantly different (P > 0.05). The total time toconsume the drink was significantly greater (P <0.05) for beer than all other liquids. The total time(7.7 ± 6.0 min) pH < 4.0 for cola wassignificantly different (P < 0.023) than beer (3.3± 3.7 min), tea/coffee (1.4 ± 6.5 min),and water (1.1 ± 2.5 min). The percentage oftotal time pH < 4.0 was not significantly different (P >0.05) among any of the liquids. The percentage of timepH < 4.0 during the drink was the highest for cola(63 ± 47%) and juice (51 ± 57%); water,coffee/tea, and beer were not significantly different (P> 0.05). Although the impact of cola and juice werethe greatest, none of these had an impact that exceeded0.5%. The lack of impact of beer appears to be due to the increased period of time it takes toconsume. We conclude that the impact of ingested fluidsis minimal and can probably be disregarded in mostpatient groups. 相似文献
99.
Anita Sydbom 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(5):567-572
Summary Rat peritoneal mast cells were exposed to the neurohormone and basic opioid peptide -endorphin. -Endorphin induced a dose-dependent release of histamine from the mast cells. A significant histamine release was found at 5 mol/l of -endorphin and maximal release (35% of total) at 20 mol/l. The histamine release process was very rapid and terminated within 30 s at 37°C, and in this sense is very similar to the histamine release induced by compound 48/80 or neurotensin. The histamine release was temperature-dependent showing an optimum release around 30°C, and it was independent of available extracellular calcium, but was inhibited in the presence of high extracellular calcium concentrations. Naloxone, only in very high concentrations (10 mmol/l), inhibited the release, and the very same concentration also inhibited the neurotensin — as well as the compound 48/80-induced histamine release. Cromoglycate and benzalkoniumchloride, a 48/80 antagonist, both produced a progressive dose-dependent inhibition of -endorphin-, neurotensin- as well as compound 48/80-induced histamine release. Taken together, the findings indicate that the opioid peptide -endorphin induces a selective, energy-dependent release of histamine from peritoneal rat mast cells. The pattern of release has much in common with that of compound 48/80 and other basic peptides, such as neurotensin and substance P. In addition this pattern of release is similar to that induced by dynorphin.
Send offprint requests to Anita Sydbom at the above address 相似文献
100.
Choremi-Papadopoulou H Tsalimalma K Dafni U Dimitracopoulou A Kordossis T 《Journal of medical virology》2004,73(2):235-243
Long-term (3.5 years) immune reconstitution in relation to viral load response was determined. Plasma HIV-1 RNA was suppressed in 40 patients (full responders) up to 42 months, and 17 patients achieved partial response. The measurements of CD4+ and CD8+ T lymphocyte subsets (CD45RA, CD45RACD62L, CD45RO, CD28, CD38) were carried out by flow cytometry. Full responders had a significant increase of CD4+ and all CD4+ T subsets both up to 6 and from 6 to 42 months, while the increase for partial responders was only up to 6 months. By 6 months, higher slopes were observed in full versus partial responders in the % of CD28 on CD4+ and the % of CD4+ memory subset and in both naïve and memory CD4+ subsets from 6 to 42 months. The percentage of CD8+ and its subsets was decreased significantly in full responders both up to 6 and from 6 to 42 months (except for an increase in the CD8+CD45RA+ CD62L+ cells), while in partial responders this decrease was only up to 6 months. Lower slopes were observed in full versus partial responders from 6 to 42 months in the percentages of CD8+, CD8+CD45RO+, CD8+CD28−, and CD8+CD38+ T cells. In conclusion, full responders have a stronger long-term naive CD4+ T cell subset reconstitution than partial responders. J. Med. Virol. 73:235–243, 2004. © 2004 Wiley-Liss, Inc. 相似文献