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21.
目的 了解湘西自治州重点人群性病患消长趋势,为性病防治工作提供科学依据。方法 从1995年起,采用统一的表格,每年对湘西州劳教所新入教人员进行一次法定性病监测。结果 三种法定性病平均患病率为14.64%(4.96~26.7%),以1995年最低,1997年最高,8年未发现HIV/AIDS,患病率以20~39岁的性跃期人群为最高,汉族患病率高于其它民族;化程度越高,患病率越低。结论 男性劳教人员作为性病患病的高危人群,是哨点监测理想的目标人群。  相似文献   
22.
Polymorphism p53 codon-72 and invasive cervical cancer: a meta-analysis.   总被引:4,自引:0,他引:4  
OBJECTIVES: Although some studies have reported that the arginine isoform on codon 72 of p53 increases the susceptibility to invasive cervical cancer, such data remain controversial. The objective of this study was to quantitatively summarize the evidence for such a relationship. METHODS: Our data sources consisted of a MEDLINE search of the literature published before December 2002, bibliography review, and expert consultation. Thirty-seven studies met the inclusion criteria. Information on sample size, study design, Hardy-Weinberg equilibrium, and method of genotype determination was abstracted by two reviewers using a standardized protocol. The overall odds ratio (OR) of the p53 gene on invasive cervical cancer was estimated using the Mantel-Haenzel method. RESULTS: The overall OR (95% confidence interval) for cervical cancer among those with the homozygous mutant (Arg/Arg) was 1.2 (1.1-1.3, P=0.001) compared with those with the heterozygous mutant (Arg/Pro). By a cellular type of cervical cancer, the overall OR among those with Arg/Arg was statistically significant in adenocarcinomas (1.7, 1.1-2.6, P=0.024), but not in squamous cell carcinomas (1.1, 0.9-1.2, P=0.960), compared with Pro/Pro. Compared with Arg/Pro, the OR among those with Arg/Arg was statistically significant in HPV types 16 (1,5, 1.2-2.0, P=0.002). CONCLUSIONS: Overall, the p53 gene was associated with increased risk for invasive cervical cancer. However, the risk varied by country, cellular, and HPV type.  相似文献   
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Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases.  相似文献   
25.
Rapid leukocyte integrin activation by chemokines   总被引:12,自引:0,他引:12  
Summary: Chemokines control selective targeting of circulating leukocytes to the microvasculature by triggering inside-out signal transduction pathways leading to integrin-dependent adhesion. Integrin activation by chemokines is very rapid, is downmodulated within minutes and appears to involve both enhanced heterodimer lateral mobility on the plasma membrane, facilitating encounters with dispersed ligand, as well as induction of a high-affinity state. These two modalities of integrin activation by chemokines involve distinct signaling pathways in the cell, yet complement each other functionally, allowing binding of rolling cells under conditions of low as well as high ligand density. Recent data show that chemokines generate both pro- and anti-adhesive intracellular signaling events, whose equilibrium is likely to be relevant to the kinetics of adhesion and de-adhesion, and to cell movement during diapedesis and chemotaxis. Importantly, chemokines utilize different signaling mechanisms to modulate the activity of distinct integrin subtypes. These recent advances suggest that chemokines may regulate adhesive responses of immune cells based not only on patterns of chemokine receptor expression, but also on variable signaling pathways that can modulate the pro-adhesive responses of leukocytes as a function of their differentiated state, and of the local microenvironment.  相似文献   
26.
分析47例骨髓穿刺干抽的临床和病理改变,干抽占同期1319例骨穿的3.6%。根据骨髓细胞的密度和间质纤维增殖的程度,把干抽的原因分为4类:高细胞伴间质细胞增多者19例(42.2%);间质细胞增多者14例(31.1%);高细胞者8例(17.8%)及低细胞者4例(8.9%)。主要疾病为:急性淋巴细胞白血病(25.5%),急性非淋巴细胞白血病(17.0%),慢性白血病(14.9%),骨髓转移瘤(10.6  相似文献   
27.
Reactive oxygen species (ROS) contribute significantly to myocardial ischaemia-reperfusion (I-R) injury. Recently the combination of the antioxidants vitamin E (VE) and alpha-lipoic acid (alpha-LA) has been reported to improve cardiac performance and reduce myocardial lipid peroxidation during in vitro I-R. The purpose of these experiments was to investigate the effects of VE and alpha-LA supplementation on cardiac performance, incidence of dysrhythmias and biochemical alterations during an in vivo myocardial I-R insult. Female Sprague-Dawley rats (4-months old) were assigned to one of the two dietary treatments: (1) control diet (CON) or (2) VE and alpha-LA supplementation (ANTIOXID). The CON diet was prepared to meet AIN-93M standards, which contains 75 IU VE kg-1 diet. The ANTIOXID diet contained 10 000 IU VE kg(-1) diet and 1.65 g alpha-LA kg(-1) diet. After the 14-week feeding period, significant differences (P<0.05) existed in mean myocardial VE levels between dietary groups. Animals in each experimental group were subjected to an in vivo I-R protocol which included 25 min of left anterior coronary artery occlusion followed by 10 min of reperfusion. No group differences (P>0.05) existed in cardiac performance (e.g. peak arterial pressure or ventricular work) or the incidence of ventricular dysrhythmias during the I-R protocol. Following I-R, two markers of lipid peroxidation were lower (P<0.05) in the ANTIOXID animals compared with CON. These data indicate that dietary supplementation of the antioxidants, VE and alpha-LA do not influence cardiac performance or the incidence of dysrhythmias but do decrease lipid peroxidation during in vivo I-R in young adult rats.  相似文献   
28.
双歧杆菌对早产儿食道pH值的影响及临床意义   总被引:2,自引:0,他引:2  
目的为探讨双歧杆菌对早产儿食道pH值的影响,及其对早产儿易发生的消化道疾病的防治意义。方法我们采用便携式24hpH值自动记录仪,对61例早产儿进行了食道pH值的动态监测。结果口服双歧杆菌活菌制剂组的30例早产儿,食道pH值明显高于未服药的对照组,t=2.4093,P<0.05。总pH值<4的时间占总观察时间的百分比显著小于对照组。并且治疗组发生消化道疾患的人数也较对照组少。结论早产儿口服双歧杆菌活菌制剂可以减少胃食道反流等消化道疾病的发生。  相似文献   
29.
The C-C chemokine RANTES, a T lymphocyte chemoattractant, is considered an important mediator of inflammation, allergy, and host defense against HIV-1 infection. In this study, we investigated the modulation of binding of RANTES to T lymphocytes. Human peripheral blood CD3+ T cells, when freshly isolated from buffy-coat blood, expressed a considerable number of high-affinity binding sites for RANTES. These cells also showed significant chemotactic migration in response to RANTES in vitro. After 6–15 h incubation at 37°C, the binding of RANTES, but not of macrophage inflammatory protein-1α (MIP-1α) or of monocyte chemotactic protein-3 (MCP-3), consistently increased. Scatchard analyses indicated that the number of binding sites for RANTES increased about threefold by 15 h without any change in the affinity. The increase in RANTES binding was no longer detected by 24 h. This increase in the specific binding was mainly attributable to CD4+ T cells and was not associated with increased chemotactic activity of these cells in response to RANTES. Incubation with anti-CD3 antibody for 15 h markedly reduced the binding capability of T cells for RANTES and was associated with decreased chemotactic activity. On the other hand, when T cells were incubated with interleukin-2 (IL-2) for 1 week, the specific binding for all three C-C chemokines, RANTES, MIP-1α, and MCP-3 was markedly increased in comparison to cells cultured in the absence of IL-2. These results suggest that the expression of binding sites on T cells for RANTES is differentially modulated, indicating the existence of novel receptors for RANTES that do not bind MIP-1α.  相似文献   
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