GB9706．1-1995中漏电流测量装置（MD）的理解和标定

GB9706．1-1995是医用电气设备的安全通用要求，其中规定的漏电流要求是所有医用电气设备必须要达到的安全要求之一。同时，GB9705．1-1995给出了漏电流的测试方法及测量装置（MD），这里我们对该测量装置的特性及漏电流测试仪器的标定进行探讨。     

甘草黄酮抗实验性心律失常的作用

甘草黄酮（ｇｌｙｃｙｒｒｈｅｉｃｂｒｓｓ．ＧＢ）２ｍｇ／ｋｇ能明显对抗乌头碱２０μｇ／ｋｇ，ＢａＣｌ２２ｍｇ／ｋｇ和结扎左冠状动脉前降支诱发大鼠的室性心律失常。甘草黄酮也能明显对抗ＣａＣｌ２－Ａｃｈ（ＣａＣｌ２０．６％＋Ａｃｈ０．００２５％）混合液诱发小鼠心房纤颤或扑动，ＧＢ对大鼠心电图实验，证明了有负性频率作用，负性传导作用，这些作用可能是ＧＢ抗心律失常作用的药理基础。     

肝细胞癌患者GB病毒C感染状况及其相关性研究

为了解ＧＢ病毒Ｃ（ＧＢＶ－Ｃ）感染与肝细胞癌（下称肝癌）之间可能的相关性,采用一步法逆转录聚合酶链反应（ＲＴ－ＰＣＲ）对１２４ 例肝癌患者进行了ＧＢＶ－ＣＲＮＡ 检测。结果：ＧＢＶ－ＣＲＮＡ 总检出率高达２６．６％ （３３／１２４）,３３ 例ＧＢＶ－ＣＲＮＡ 检出阳性者中,９０．９％ 合并有ＨＢＶ、ＨＣＶ感染;３３ 例非Ｂ非Ｃ型肝癌中,ＧＢＶ－ＣＲＮＡ检出率为９．１％ （３／３３）。３３ 例ＧＢＶ－Ｃ感染阳性肝癌患者中,９０．０％ （３０／３３）有既往输血史,高于ＧＢＶ－Ｃ感染阴性组（４８／９１）。上述结果提示,我国肝癌患者中ＧＢＶ－Ｃ感染的检出率高于美、欧、日等地同类患者的检出率,其在肝细胞癌及输血后肝炎发生中的病因学意义值得注意。     

光明、太冲穴与中枢神经相关效应的观察

目的:观察针刺光明、太冲穴时,中枢不同区域的相关反应.方法:将19名正常志愿者随机分为1组(视觉刺激加单侧针刺组)7人,2组(视觉刺激加双侧针刺组)6人和3组(单纯针刺双侧穴组)6人.用功能性磁共振(fMRI)观察各组在针刺光明、太冲穴时视觉皮质区与相关脑区的反应.结果:发现视觉刺激及针刺进针时,视觉皮质的血氧饱和水平(BOLD)无明显变化(P＞0.25),但在进行单侧和双侧持续刺激时,发现大脑相关区域有BOLD变化.结论:针刺对单侧和双侧穴位的刺激均能改善大脑相关区域的BOLD,但与进行手法和视觉刺激无关.     

Dipole tensor-based atomic-resolution structure determination of a nanocrystalline protein by solid-state NMR

Magic-angle spinning (MAS) solid-state NMR (SSNMR) techniques have emerged in recent years for solving complete structures of uniformly labeled proteins lacking macroscopic order. Strategies used thus far have relied primarily on semiquantitative distance restraints, analogous to the nuclear Overhauser effect (NOE) routinely used in solution NMR. Here, we present a complementary approach for using relative orientations of molecular fragments, determined from dipolar line shapes. Whereas SSNMR distance restraints typically have an uncertainty of approximately 1 A, the tensor-based experiments report on relative vector (pseudobond) angles with precision of a few degrees. By using 3D techniques of this type, vector angle (VEAN) restraints were determined for the majority of the 56-residue B1 immunoglobulin binding domain of protein G [protein GB1 (a total of 47 HN-HN, 49 HN-HC, and 12 HA-HB restraints)]. By using distance restraints alone in the structure calculations, the overall backbone root-mean-square deviation (bbRMSD) was 1.01 +/- 0.13 A (1.52 +/- 0.12 A for all heavy atoms), which improved to 0.49 +/- 0.05 A (1.19 +/- 0.07 A) on the addition of empirical chemical shift [torsion angle likelihood obtained from shift and sequence similarity (TALOS)] restraints. VEAN restraints further improved the ensemble to 0.31 +/- 0.06 A bbRMSD (1.06 +/- 0.07 A); relative to the structure with distances alone, most of the improvement remained (bbRMSD 0.64 +/- 0.09 A; 1.29 +/- 0.07 A) when TALOS restraints were removed before refinement. These results represent significant progress toward atomic-resolution protein structure determination by SSNMR, capabilities that can be applied to a large range of membrane proteins and fibrils, which are often not amenable to solution NMR or x-ray crystallography.     

A cross-sectional study on HGV infection in a rural population

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The effect of GB21 acupressure on pain intensity in the first stage of labor in primiparous women: A randomized controlled trial

IntroductionLabor pain is one of the most intensive pains experienced by women; it results in physical, emotional, and physiological changes in women’s body. The present study aimed to examine the effect of GB21 acupressure on labor pain.DesignIn this randomized clinical trial, 174 primiparous women in their first stage of labor were selected and assigned to three groups: GB21 acupressure group (n = 58), sham group (n = 58), and control group (n = 58).InterventionsThe acupressure and sham groups received routine labor care and acupressure in three different phases of cervical dilations to 3−5 cm, 6−7 cm, and 8−10 cm. The control group received routine care in labor.Main outcome measuresPain severity was measured using a pain scale ruler in three cervical dilations before and after intervention. The collected data were analyzed using the ANOVA, Kruskal–Wallis, paired-t test and Mann–Whitney tests.ResultsPain reduction was significantly higher in GB21 groups compared with sham and control groups (P = 0.001). No statistically significant difference was observed between the three groups in terms of delivery outcomes.ConclusionsIn this study, GB21 acupressure was effective in pain relief during labor, hence recommended as a practical, effective, inexpensive, and accessible method for labor pain management.     

巢式PCR检测庚型肝炎病毒感染

目的探讨逆转录-巢式PCR研究庚型肝炎病毒(HGV)感染在我国南方人群中的分布。方法从HGV 5-′NCR区段设计了内、外引物对,运用逆转录-巢式PCR对来自我国南方深圳、广州和桂林三个城市总共403例,且来自不同人群组的血清/血浆标本中HGV RNA感染率进行了研究。结果献血员人群中HGV RNA的平均感染率为5.8%(11/189),其中职业献血员较义务献血员高〔9.7%(10/102)及1.1%(1/87)〕;静脉药瘾者、丙型肝炎、乙型肝炎患者人群中HGV感染率依次为50.8%(33/65)、24.0%(9/37)、2.5%(1/40);在具有严重程度不同的非A-E肝脏疾病患者中HGV RNA阳性检出率为12.5%(9/22)。结论HGV与HCV合并感染极其常见,可能与其具有共同的传播途径有关。追踪临床资料,发现HGV的感染并未加重丙型肝炎患者的病情;多次静脉滴注药物、输血/输液、血液透析所致医院感染均是引起我国人群中HGV分布较高的重要危险传播因素;HGV的致病性较弱,可能不是引起非A-E肝脏疾病的主要致病因素。     

庚型肝炎病毒基因组RNA的实验转染

目的：研究庚型肝炎病毒（HGV）对恒河猴的致病性及其在恒河猴体内的复制和表达。方法：体外转录制备全长HGV基因组RNA，肝内注射感染BY1猴，9个月后取其阳性血清感染BM1猴，7个月后取BM1阳性血清感染BB1。采用RT－PCR、原位杂交、定量PCR和免疫学、血清酶学、组织病理学等方法，对HGV的感染性及致病性进行了研究。结果：BY1、BM1和BB1实验猴感染后，分别在第3、8和3周血清HGV RNA阳转，持续存在最长达21周。血清丙氨酸转移酶（ALT）均升高，最高达418IU／L。感染后血清中均检测出抗－HGV。肝组织检查呈现轻度肝炎样变，并检测到HGV mRNA和HGV E2蛋白在肝组织中的表达。结论：体外转录的HGV基因组RNA对恒河猴具有感染性，可在恒河猴中传代感染并引起肝组织轻微炎症改变。恒河猴对HGV感染敏感，可作为研究HGV的实验动物模型。     

关于悬钟穴定位的探讨

长久以来,关于悬钟穴的定位在学术界存在诸多看法,笔者通过查阅古代主要针灸文献及建国后高等中医院校教材、国家标准和较有影响的针灸著作中关于悬钟穴的定位,分析从古至今该穴定位的演变,认为该穴应该定位于外踝上3寸,胫骨前嵴和腓骨前缘之间.并对该穴定位出现问题的原因和时间进行了分析.