血清鸢尾素、脂联素水平与颈动脉粥样硬化的关系

目的 探讨血清鸢尾素及脂联素（APN）水平与颈动脉粥样硬化的关系。方法 选取2020年1月—2022年1月海南省人民医院收治的124例H型高血压患者作为研究组,另选取同期来该院体检的健康者112例作为对照组。比较两组血清鸢尾素、APN水平,分析研究组颈动脉粥样硬化斑块形成的影响因素,采用受试者工作特征（ROC）曲线分析血清鸢尾素、APN水平预测颈动脉粥样硬化斑块形成的价值。结果 研究组血清鸢尾素、APN水平低于对照组（P <0.05）。斑块形成组与非斑块形成组性别、年龄、体重指数、吸烟史、饮酒史、收缩压、舒张压、血压控制良好、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、一氧化氮、尿酸、肌酐、内皮素水平比较,差异无统计学意义（P>0.05）。斑块形成组甘油三酯、同型半胱氨酸水平高于非斑块形成组（P <0.05）,鸢尾素、APN水平低于非斑块形成组（P <0.05）。多因素一般Logistic回归分析结果显示：同型半胱氨酸水平[■=4.415(95%CI:1.817,10.730)]、血清鸢尾素水平[■=4.027(95%CI:1.657,9.787)]、AP...     

The essential role of stimulus temporal patterning in enabling perceptual learning

Little is known about how temporal stimulus factors influence perceptual learning. Here we demonstrate an essential role of stimulus temporal patterning in enabling perceptual learning by showing that 'unlearnable' contrast and motion-direction discrimination (resulting from random interleaving of stimuli) can be readily learned when stimuli are practiced in a fixed temporal pattern. This temporal patterning does not facilitate learning by reducing stimulus uncertainty; further, learning enabled by temporal patterning can later generalize to randomly presented stimuli.     

镉对培养大鼠睾丸支持细胞的损伤及黄芪的拮抗作用

目的:探讨镉对培养大鼠睾丸支持细胞的损伤及黄芪的保护作用.方法:对照组和经镉、镉加黄苠处理的原代培养大鼠睾丸支持细胞用于波形蛋白、E-钙黏蛋白免疫组织化学检测、细胞内钙离子浓度测定及电镜观察.结果:镉处理后2种蛋白阳性产物表达较对照组减弱.镉加黄芪组阳性产物较对照组减弱但明显强于镉组.对照组、镉和镉加黄苠组细胞内钙离子浓度分别为(81.773±3.711)、(161.6024±1.978)和(104.278±1.963).镉处理后支持细胞超微结构受损明显,部分细胞核异染色质凝聚或核碎裂,胞质空泡化.镉加黄芪组细胞破坏较轻.结论:镉对培养支持细胞具有明显的毒性作用,而黄苠可以拮抗镉对支持细胞的损伤.     

CVB3-VP1基因免疫诱导特异性抗病毒免疫应答及保护作用

目的 :构建表达柯萨奇病毒B3(CVB3)主要包膜蛋白VP1的基因疫苗 ,并研究该疫苗诱导CVB3特异性免疫应答及免疫保护的作用。方法 :抽提CVB3RNA ,以RT PCR扩增VP1基因 ,克隆于真核表达载体 pcDNA3中 ,构建质粒pcDNA3 VP1。将该质粒转染Hela细胞 ,观察其表达情况 ;以 5 0 μgpcDNA3 VP1质粒DNA肌注免疫BALB/c小鼠 3次 ,检测CVB3特异性体液和细胞免疫应答。间隔 4wk以 5×LD50 的CVB3攻击小鼠 ,观察攻击后小鼠的存活情况。结果 :构建了重组质粒 pcDNA3 VP1,并在体外获得有效表达。以该质粒肌肉免疫BALB/c小鼠 ,可诱生高水平的IgM和IgG ,VP1多肽特异性淋巴细胞增殖反应及CTL活性均显著高于 pcDNA3免疫的对照组。病毒攻击试验表明 ,pcDNA3 VP1免疫组33.3%小鼠可长期存活 ,其心肌组织未见明显的病理学改变 ;而对照小鼠平均仅存活 6 .7d ,心肌显示大量的局灶性坏死和炎性细胞浸润。结论 :pcDNA3 VP1免疫可诱生CVB3特异性体液及细胞免疫应答 ,保护免疫小鼠抵抗CVB3的致死性攻击     

The calpain system

The calpain system originally comprised three molecules: two Ca2+-dependent proteases, mu-calpain and m-calpain, and a third polypeptide, calpastatin, whose only known function is to inhibit the two calpains. Both mu- and m-calpain are heterodimers containing an identical 28-kDa subunit and an 80-kDa subunit that shares 55-65% sequence homology between the two proteases. The crystallographic structure of m-calpain reveals six "domains" in the 80-kDa subunit: 1). a 19-amino acid NH2-terminal sequence; 2). and 3). two domains that constitute the active site, IIa and IIb; 4). domain III; 5). an 18-amino acid extended sequence linking domain III to domain IV; and 6). domain IV, which resembles the penta EF-hand family of polypeptides. The single calpastatin gene can produce eight or more calpastatin polypeptides ranging from 17 to 85 kDa by use of different promoters and alternative splicing events. The physiological significance of these different calpastatins is unclear, although all bind to three different places on the calpain molecule; binding to at least two of the sites is Ca2+ dependent. Since 1989, cDNA cloning has identified 12 additional mRNAs in mammals that encode polypeptides homologous to domains IIa and IIb of the 80-kDa subunit of mu- and m-calpain, and calpain-like mRNAs have been identified in other organisms. The molecules encoded by these mRNAs have not been isolated, so little is known about their properties. How calpain activity is regulated in cells is still unclear, but the calpains ostensibly participate in a variety of cellular processes including remodeling of cytoskeletal/membrane attachments, different signal transduction pathways, and apoptosis. Deregulated calpain activity following loss of Ca2+ homeostasis results in tissue damage in response to events such as myocardial infarcts, stroke, and brain trauma.     

32例再生障碍性贫血的微循环及血液粘度

对３２例再障患者的甲襞、球结膜微循环及血粘度进行观察，结果表明：再障组均有不同程度的微循环异常改变（１００％），与正常对照组比较差异显著（Ｐ＜０．０１）；再障组全血粘度、全血还原粘度明显低于正常对照组（Ｐ＜０．０１），再障患者的Ｈｂ与全血粘度及血浆比粘度呈正相关。     

Molecular epidemiology of macrolide resistance in neonatal bloodstream isolates of group B streptococci

Pulsed-field gel electrophoresis (PFGE) was performed on 122 neonatal bloodstream isolates of group B streptococci (GBS) to further examine the relationship between macrolide resistance and serotype V GBS (GBS-V). Over one-third (35%) of macrolide-resistant GBS belonged to a single PFGE subtype of GBS-V, which was also the most common GBS-V subtype noted in previous Centers for Disease Control and Prevention surveillance studies. Erm methylase (ermA and ermB) was the most common resistance mechanism detected, present in 12 of 20 macrolide-resistant GBS.     

Clinical evaluation of a frozen commercially prepared microdilution panel for antifungal susceptibility testing of seven antifungal agents, including the new triazoles posaconazole, ravuconazole, and voriconazole

A commercially prepared frozen broth microdilution panel (Trek Diagnostic Systems, Westlake, Ohio) was compared with a reference microdilution panel for antifungal susceptibility testing of two quality control (QC) strains and 99 clinical isolates of Candida spp. The antifungal agents tested included amphotericin B, flucytosine, fluconazole, itraconazole, posaconazole, ravuconazole, and voriconazole. Microdilution testing was performed according to NCCLS recommendations. MIC endpoints were read visually after 48 h of incubation and were assessed independently for each microdilution panel. The MICs for the QC strains were within published limits for both the reference and Trek microdilution panels. Discrepancies among MIC endpoints of no more than 2 dilutions were used to calculate the percent agreement. Acceptable levels of agreement between the Trek and reference panels were observed for all antifungal agents tested against the 99 clinical isolates. The overall agreement for each antifungal agent ranged from 96% for ravuconazole to 100% for amphotericin B. The Trek microdilution panel appears to be a viable alternative to frozen microdilution panels prepared in-house.     

Phyllodes tumors of the breast: the role of pathologic parameters

We aimed to establish whether morphologic parameters were prognostically important in a large series of breast phyllodes tumors in Asian women. Of 335 phyllodes tumors diagnosed at the Department of Pathology, Singapore General Hospital, Singapore, between January 1992 and December 2002, 250 (74.6%) were benign, 54 (16.1%) borderline, and 31 (9.3%) malignant, based on histologic review of archival slides. Of the women, 43 (12.8%) experienced recurrences during the follow-up period. Recurrent disease was correlated with grade or classification (P = .028), stromal atypia (P = .016), stromal hypercellularity (P = .046), and permeative microscopic borders (P = .021). Multivariate analysis revealed that independent predictors of recurrence were pseudoangiomatous stromal hyperplasia (PASH) and margin status, whereby the presence of PASH and complete or negative margins reduced recurrence hazards by 51.3% and 51.7% respectively. The 7 women who died of disease during follow-up had malignant phyllodes tumor at the outset and experienced recurrences, and death was preceded by distant metastases.     

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。