41例女性慢性输血后丙型肝炎10～15年后的感染状态

目的　了解我国女性输血后丙型肝炎病毒 (HCV)感染的慢性化规律和影响因素。方法　对河北省固安县 1989～ 1993年 4 1例女性慢性输血后丙型肝炎患者的现状进行调查 ,包括临床表现 ,血清生物化学指标 ,病毒学标志检测及B型超声检查。其中 ,HCVRNA的测定采用荧光定量PCR方法 ,抗 HIV ,抗 HCV和HBsAg测定采用酶联免疫吸附试验。结果　 4 1例女性丙型肝炎患者平均年龄 (40± 7)岁 ,随访时间 10～ 15年 ,HCVRNA间隔半年两次检测 ,自然阴转率为 19 5 1% (8 4 1)。 30例(73% )现在有症状 ,以乏力最为常见 (77% )。总的丙氨酸转氨酶 (ALT)和 (或 )天冬氨酸转氨酶 (AST)异常率为 32 % (13 4 1) ,均为轻度异常 ,无中度和重度。B超轻度慢性肝炎占 83% (34 4 1) ,中度占 17%(7 4 1) ,无重度。结论　平均感染 (13± 1)年的女性输血后慢性丙型肝炎患者多数肝脏炎症轻微慢性感染进程中有部分感染者出现HCVRNA自发阴转。     

组织工程在周围神经缺损修复中的应用

近年来组织工程学的迅速发展使其在周围神经修复方面有了，“阔的发展空间。组织工程的核心是建立细胞与生物材料的三维空间复合体，即具有生命力的活体组织，用以对病损组织进行形态、结构和功能的重建并达到永久性替代。其重点问题包括：导管材料的选择以及神经生长的微环境。     

基于边界特征的乳腺肿瘤超声图像识别

通过对乳腺肿瘤边界特征的分析，得到边界的特征量似圆度，面积比率，长宽比组成的特征矢量，最后用反向传播人工神经网络（BP）的算法对经病理证实的119幅乳腺良、恶性肿块超声图像进行分类识别。BP神经网络对良、恶性肿瘤正确识别率分别为89．7％、73．5N。量化后的乳腺超声图像肿瘤轮廓特征结合BP神经网络可以比较有效的用于肿瘤的良、恶性识别。     

Analysis of the influence of therapy and viral suppression on high-risk sexual behaviour and sexually transmitted infections among patients infected with human immunodeficiency virus in Taiwan

This study examined the effects of certain characteristics of human immunodeficiency virus (HIV)-infected patients related to the risks of practising unprotected sex (UPS) among 919 HIV-infected patients who attended the sexually transmitted disease (STD) clinic of the Taipei City STD Control Center, Taiwan, during the period January–July 2004. After learning that they were HIV-positive, 517 (56%) subjects had practised UPS, 476 (52%) had a new STD diagnosis, and 106 (12%) had used some form of injected drug. UPS was reported by 76% of homosexual/bisexual males, 19% of heterosexual males and 5% of females, and was reported more often by those individuals with casual sexual partners (p < 0.001). According to multivariate logistic regression analyses, UPS was associated with male-tomale sexual intercourse (OR 2.46; 95% CI 1.26–4.86, p < 0.001), with casual sexual partners (OR 2.82; 95% CI 1.62–4.88, p < 0.001), and with an individual's knowledge of his/her HIV status for > 11 years (OR 2.06; 95% CI 1.02–4.18, p < 0.05). Although using anti-retroviral therapy to prevent sexual transmission of HIV is rational, the avoidance of at-risk sexual behaviour should also be a priority among HIV-seropositive individuals. Ongoing risk-reduction counselling related to HIV transmission is needed to reduce certain sexual behaviours associated with HIV transmission.     

PCR 检测产 A、B、E、F 和 G 型肉毒神经毒素梭菌的神经毒素基因

肉毒神经毒素分为Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ和Ｇ七个血清型，其中Ａ、Ｂ、Ｅ和Ｆ型引起人类肉毒中毒。为此，选取肉毒神经毒素的保守序列设计了一对简并引物，对１８株肉毒梭菌和８株相关梭菌进行了检测，表明该引物可特异扩增Ａ、Ｂ、Ｅ、Ｆ和Ｇ型肉毒梭菌及产Ｅ型肉毒神经毒素的丁酸梭菌，产物为２６４ｂｐ，敏感性达１０ｐｇ细菌ＤＮＡ。采有酚－氯仿抽提法、固相载体捕获法和热裂解法处理产毒菌株，结果表明热裂解法安全、简便、快速，所制模板扩增效果明显。因此，此ＰＣＲ方法可用于快速敏感地检测引起人类肉毒中毒的梭菌。     

立体定向治疗中靶心定位的算法

本文介绍了在立体定向放射神经外科中，根据病人配戴头环和ＣＴ定标架作ＣＴ扫描所得的ＣＴ断层图像或配戴ＡＶＭ定位箱做血管造影得到的两张Ｘ光片确定病人颅内病灶的三维坐标的方法。     

The self antigen heme evades immune recognition by sequestration in some hemoproteins

Heme is a non-protein autoantigen which is ubiquitous in vivo, primarily complexed in various hemoproteins or bound to specialized carrier molecules. Nevertheless, heme is able to stimulate a high frequency of CD4⁺, class II-restricted T cells, freshly explanted from unprimed mice, to proliferate in vitro. In this study, we show that heme incorporated into various species of mammalian cytochrome c (cyt c), including murine cyt c, represents a facultative cryptic determinant, able to be recalled only at high doses of native cyt c. By contrast, avian cyt c is of comparable antigenicity to free heme. Artificially denatured carboxymethylated (CM) mammalian cyt c exhibited greatly increased antigenicity, comparable to that of heme and avian cyt c, indicating that the crypticity of heme in native mammalian cyt c is due to the resistance of the native conformation of this molecule to antigen processing within murine antigen-presenting cells. Thus, tolerance to the heme group of at least some hemoproteins, may be maintained by the crypticity of the heme, rather than by deletion of hemereactive T cells. Given the high frequency of heme-reactive T cells in unprimed mice, these findings suggest that heme may become an important modulator during an inflammatory response.