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91.
Objective: The objective of this study was to determine whether human papillomavirus (HPV) infections are involved in the development of papillomatosis lesions of the lower female genital tract.Methods: A total of 616 biopsy specimens of genital papillomatous lesions (307 nodular and 309 papular types) from 598 patients were anaylyzed for the presence of HPV DNA sequences by polymerase chain reaction (PCR). These specimens were also examined by histopathological assessment for characteristic HPV-associated cytological changes, by immunohistochemical staining for HPV-associated antigen, and by electron microscopy for the presence of virions.Results: HPV DNA sequences were found in 97.9% (140 of 143 cases) and 1.1% (1 of 91 cases) of the nodular and papular papillomatosis cases tested, respectively. In 18 patients who had both types of papillomatosis lesions, HPV DNA was invariably found only in nodular tissues. HPV-associated antigen, koilocytosis, and virions were found in 53.6% (98 of 183 cases), 70.5% (129 of 183 cases), and 5.9% (5 of 85 cases) of nodular papillomatosis lesions tested, respectively.Conclusions: These data suggest that nodular papillomatosis was closely associated with HPV infection, but that papular papillomatosis of the lower female genital tract may have an etiology other than HPV infection.  相似文献   
92.
目的 分析我国消除丙型肝炎(丙肝)的普通人群HCV检测策略的成本效果,明确最佳成本效果的HCV检测年龄。方法 运用TreeAge pro 2019软件构建决策树马尔科夫模型,以1年为周期,模拟10万名20~59岁各年龄组人群HCV检测和治疗结果,以全社会角度分析策略间比较的成本效果和效益。效果指标为增量成本效果比(ICER),效益指标为净货币效益(NMB),以我国2022年人均国内生产总值(85 698元)为意愿支付阈值。通过单因素敏感性分析和概率敏感性分析评估结果可靠性。结果 在20~59岁人群HCV检测有成本效果,在40~49岁年龄组进行HCV检测成本效果最佳。20~59岁年龄组人群HCV检测策略与未HCV检测策略比较,增量成本为161.24元/人,增量效用为0.003 6质量调整寿命年(QALYs)/人,ICER为45 197.26元/QALY,ICER小于意愿支付阈值,具有成本效果。各年龄组人群HCV检测策略与未HCV检测策略比较,ICER为42 055.06~53 249.43元/QALY,NMB为96.52~169.86元/人,其中40~49岁年龄组的ICER最低,NMB最高。单因素敏感性分析结果显示,贴现率、丙肝抗体(抗-HCV)检测成本、人群抗-HCV阳性率和直接抗病毒药物治疗成本对经济学评价影响较大,但改变参数取值,结论不变。概率敏感性分析结果表明模型分析结果稳定。结论 医疗机构探索动员20~59岁普通人群进行HCV检测具有较好的成本效果,以40~49岁年龄组人群的HCV检测成本效果最佳。在我国普通人群中实施HCV检测的“愿检尽检”策略,能降低人群丙肝疾病负担。  相似文献   
93.
目的探讨试剂对VCA-IgA抗体检测结果的影响.方法用不同厂家或同一厂家不同批号之试剂盒分别检测同一批血清或同一批人群不同时期血清的VCA-IgA,进行横向和纵向比较.结果①同一批血清用不同试剂盒检测结果完全相同占35.58%和35.59%,完全相反占15.38%和13.56%,差异一个滴度占28.85%和36.44%,差异二个滴度以上占20.19%和14.41%;②同一人群不同时期血清因用同一厂家不同批号试剂,所得结果完全相同占36.99%,完全相反占13.70%,差异一个滴度占32.88%,差异二个滴度以上占16.43%;③广东C试剂盒无论是检测同一批血清,还是检测同一批人不同时期血清,所得阳性率及其滴度均显著高于广西出品的试剂盒.结论①同一个人在不同时间、地点检测结果可能差异很大;②一个医院应相对稳定使用同一厂家试剂盒;③对比同一个人不同时期的抗体变化,应用同一批试剂同时检测,才具有良好的对比性.  相似文献   
94.
Cannabis use and cognitive decline in persons under 65 years of age   总被引:2,自引:0,他引:2  
The purpose of this study was to investigate possible adverse effects of cannabis use on cognitive decline after 12 years in persons under age 65 years. This was a follow-up study of a probability sample of the adult household residents of East Baltimore. The analyses included 1,318 participants in the Baltimore, Maryland, portion of the Epidemiologic Catchment Area study who completed the Mini-Mental State Examination (MMSE) during three study waves in 1981, 1982, and 1993-1996. Individual MMSE score differences between waves 2 and 3 were calculated for each study participant. After 12 years, study participants' scores declined a mean of 1.20 points on the MMSE (standard deviation 1.90), with 66% having scores that declined by at least one point. Significant numbers of scores declined by three points or more (15% of participants in the 18-29 age group). There were no significant differences in cognitive decline between heavy users, light users, and nonusers of cannabis. There were also no male-female differences in cognitive decline in relation to cannabis use. The authors conclude that over long time periods, in persons under age 65 years, cognitive decline occurs in all age groups. This decline is closely associated with aging and educational level but does not appear to be associated with cannabis use.  相似文献   
95.
目的:探讨糖皮质激素治疗流行性乙型脑炎的疗效。方法:采用地塞米松针剂加入液体静脉滴注,并配合物理降温、镇静止痉、脱水、给氧、扩容、纠酸、防治感染,加强护理等常规综合治疗。结果:治愈69例(908%),好转3例(39%),死亡4例(53%)。结论:在常规综合治疗基础上应用激素治疗乙型脑炎疗效显著提高。  相似文献   
96.
This work investigated whether turbo magnetic resonance angiography (MRA) can replace conventional MRA in screening examination of intracranial arteries. A phantom was used to evaluate the effect of the zero-filling interpolation (ZFI) technique on spatial resolution and partial volume effect. Thirty-one consecutive patients underwent both turbo MRA with a slice thickness of 0.7 mm (data were measured as 1.33 mm sections) and conventional MRA with 1.0 mm sections. In the phantom studies, ZFI did not improve the spatial resolution, but the partial volume effect was somewhat reduced. In the clinical evaluation, turbo MRA showed better signal-to-noise and contrast-to-noise ratios of the intracranial major vessels than conventional MRA. The lesions included cerebral aneurysms less than 3 mm in diameter, occlusive vascular disease, arteriovenous malformations, and arteriovenous fistulas. These were all depicted on both turbo MRA and conventional MRA. Turbo MRA is a useful screening procedure because of its capability of delineating lesions in approximately half the usual imaging time. J. Magn. Reson. Imaging 1999;10:939-944.  相似文献   
97.
Aim: To study the behavior of external urethral sphincter in chronic prostatitis (CP) patient under natural filling.Methods: Twenty-one CP patients and 17 normal volunteers were involved in the study. Both the patients andvolunteers underwent ambulatory urodynamic monitoring (AM) and conventional medium filling cystometry (CMG).Urodec 500 was used for AM and Menuet for CMG. AM findings from CP patients were compared with those fromnormal volunteers, and the results from AM were compared with those from CMG. Results: In AM, the restingand voiding external urethral sphincter (EUS) pressures and maximum urethral closure pressures (MUCP) weresignificantly higher in CP patients [ ( 121.5 ±10.3) and (85.6±3.5) cm water, respectively ] than in normalvolunteers [ (77.6±11.4) and (10.3±1.6) cm water, respectively)]. Conclusion: The behavioral changes ofEUS in CP patients included spasm and instability of EUS, which were demonstrated using AM under natural filling;the findings were also in accord with the res  相似文献   
98.
To understand the clonal relationship of various olfactory bulb (OB) cell types, OB progenitor cells were infected at embryonic day (E) 14, E15, and E17 with retroviral libraries encoding alkaline phosphatase or beta-galactosidase. After survival to postnatal day 10-15, sibling relationships were identified by polymerase chain reaction DNA amplification of distinct sequences in the retroviral constructs. Within the OB, clonal progeny dispersed widely in all directions. In sharp contrast, however, clonal dispersion between the OB and neocortex was not observed, although occasional clonal dispersion between the OB and pyriform and hippocampal regions could not be excluded. Most clones (84%) contained a single cell type, especially after E17 injections, suggesting the existence of either restricted precursors, or multipotential progenitors instructed by a restricted cellular environment. Mixed OB clones (16%) contained multiple cell types in the OB, or occasionally glial or neuronal cells outside the OB, demonstrating the existence of multipotential OB progenitors, likely at a stage before formation of the olfactory rostral migratory stream. Surprisingly, OB glial cells were not labeled, suggesting distinct lineages or perhaps distinct migratory paths for glia and neurons into the OB. A hierarchical cell lineage is proposed that involves a multipotential progenitor that gives rise to potentially more limited progenitors.  相似文献   
99.
The distribution of secretoneurin (SN), a peptide derived from secretogranin II (SgII), in the coeliac ganglion, the splenic nerve and the spleen was examined by immunohistochemistry. In the ganglion, SN immunoreactivity (IR) was unevenly distributed. Positive nerve terminals densely surrounded some postganglionic perikarya in which also intense SN-IR was present. In the crushed splenic nerves, intense immunoreactivities appeared proximal (but to a less extent also distal) to the crush of the nerve. Analysis by cytofluorimetric scanning (CFS) demonstrated that SN-IR and neuropeptide Y immunoreactivity (NPY-IR) were predominant in the axons proximal to the crush representing anterogradely transported components. Using radioimmunoassay (RIA) we demonstrated that upon electrical stimulation (10 Hz, 1 min) of the splenic nerve, significant amounts of SN-IR (64.2+/-2.3 fmol) were released together with NA (4. 1x106+/-0.2 fmol) and NPY (330.0+/-7.2 fmol) from the isolated perfused porcine spleen. To evaluate the processing of SgII in sympathetic neurons, boiled tissue extracts (coeliac ganglia and splenic nerve) and boiled spleen perfusate (used as a suitable source for vesicle derived peptides) were analysed by gel filtration chromatography followed by SN-RIA. In all cases immunoreactivity was present solely as SN, indicating that SgII was fully processed to the free peptide. The evidence that SN is transported to the nerve terminals and is released from the porcine spleen upon nerve stimulation, suggests that it may modulate adrenergic neurotransmission and may also play a role in the neuroimmune communication.  相似文献   
100.
BACKGROUND: Exposure of prostate carcinoma cell lines to retinoids, which function through the classical retinoic acid nuclear receptor, (RARs) or retinoid X receptors (RXRs), results in minimal cytostatic inhibition of cell proliferation. METHODS: Growth inhibition and various regulatory responses were investigated in two human prostate carcinoma cell lines (LNCaP and PC-3) treated with or without a synthetic retinoid, CD 437. RESULTS: Incubation of prostate carcinoma cell lines with a novel retinoid CD437 resulted in the marked inhibition of proliferation. LNCaP and PC-3 possessed IC50 values for CD437 of 375 nM and 550 nM, respectively. Incubation with 1 microM CD437 for 24 hr resulted in 100% and 60% inhibition of growth in LNCaP and PC-3 cells, respectively. Simultaneously, cell flow cytometric analyses revealed a dramatic increase of the cell population in S phase, in both LNCaP (from 38.6% up to 86.7%) and PC-3 (27.9% to 55.7%), and a decreased proportion of cells in G2 phase, in LNCaP (from 23.7% down to 1.2%) and PC-3 (14.9% to 2.2%), indicating a significant S-phase arrest. The cell growth inhibition and S-phase arrest in these cells were followed by apoptosis, as revealed by the acquisition of the characteristic cell morphology including the appearance of apoptotic bodies, and further confirmed by cellular DNA fragmentation. CD437-induced-S phase arrest was associated with upregulated mRNA levels of p21waf1/cip1/sdi1 in both LNCaP (p53+/+) and PC-3 (53-/-) cells. CONCLUSIONS: CD437 represents a unique retinoid that induces S-phase arrest and apoptosis in both androgen-dependent (LNCaP) and -independent (PC-3) human prostate cancer cells, suggesting a potential role of CD437 in the treatment of human prostate cancer.  相似文献   
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