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121.
National examinations for medical graduates were introduced on an experimental basis in the People's Republic of China in 1982. To estimate the predictive validity of the National Medical Examination (NME), an investigation of the postgraduate competence of a sample of the participating examinees was conducted in 1984. The sample consisted of 1,717 of the 4,995 graduates from 13 medical colleges who had taken the initial NME. Their scores on the NME and the ratings given them by directors of postgraduate programs in nine aspects of clinical competence were compared by frequency distribution and product-moment correlation coefficients. Scores on the NME were consistent with measures of postgraduate clinical competence and, as a whole, correlated significantly with the ratings of clinical competence, supporting the use of the score on the NME as a predictor of postgraduate clinical competence. However, the extent of the relationship between the NME score and postgraduate clinical competence varied according to the specialty program of postgraduate medical training.  相似文献   
122.
乙/丙型肝炎病毒双重感染患者前C区终止变异低频率   总被引:1,自引:0,他引:1  
目的了解乙型肝炎病毒(HBV)与丙型肝炎病毒(HCV)双重感染患者前C区基因变异,及其可能的临床意义。方法用聚合酶链反应(PCR)与限制片段长度多态性(RFLP)来分析25例HBVDNA和HCVRNA均阳性(A组)和31例HBsAg和HBVDNA阳性但抗-HCV和HCVRNA均阴性(B组)的慢性肝病患者前C区密码28终止变异(终28)。结果HBV和HCV双重感染患者(A组)血清HBVDNA第1次PCR阳性率(16%)明显低于单独HBV感染组(65%)(P<0.001);前C终28检出率(28%)亦明显低于单独HBV感染(68%)(P<0.001)。结论提示双重感染患者HBV前C终止变异低频率可能与HBV低水平复制有关  相似文献   
123.
We report that the tumor neurosis factor homolog APRIL (a proliferation-inducing ligand) stimulates in vitro proliferation of primary B and T cells and increases spleen weight due to accumulation of B cells in vivo. APRIL functions via binding to BCMA (B cell maturation antigen) and TACI (transmembrane activator and CAML-interactor) and competes with TALL-I (also called BLyS or BAFF) for receptor binding. Soluble BCMA and TACI specifically prevent binding of APRIL and block APRIL-stimulated proliferation of primary B cells. BCMA-Fc also inhibits production of antibodies against keyhole limpet hemocyanin and Pneumovax in mice, indicating that APRIL and/or TALL-I signaling via BCMA and/or TACI are required for generation of humoral immunity. Thus, APRIL-TALL-I and BCMA-TACI form a two ligands-two receptors pathway involved in stimulation of B and T cell function.  相似文献   
124.
应用放射免疫法对112例、170例和113例新生儿脐血分作ANF、CG和β_2测定。结果:(1)早产儿和地期产儿ANF、CG和β_2-m的含量显著高于正常足月儿,与正常儿比较P值分别为:P<0.001、P<0.01、P<0.05。(2)高危新生儿出生1分钟Apgar评分越低,脐血ANF、CG和β_2m的含量越高。Apgar评分0′~3′和4′~7′组脐血ANF、CG和β_2-m含量高于8′~10′组。(3)高危儿的转归不同,脐血ANF、CG和β_2-m含量差异也极为显著。抢救成活组、死亡组脐血ANF、CG和β_2-m含量明显高于正常成活组(P值均<0.01)。(4)本文经抢救和死亡高危儿共27例同时检测了上述三项指标ANF、CG、β_2-m的含量呈高度正相关。 研究结果表明,高危新生儿ANF、CG和β_2-m的含量越高,心、肝、肾功能受损程度越严重。因此,脐血ANF、CG和β_2-m可客观而可靠地反映高危新生儿心、肝、肾功能,具有较高的临床应用价值。  相似文献   
125.
目的 研究α-突触核蛋白(α-synuclein,α-SYN)过表达对多巴胺能神经元酪氨酸羟化酶(TH)表达的影响。方法 在α—SYN基因转染的MES 23.5大鼠黑质多巴胺能神经元细胞系,分别用免疫组织化学、免疫荧光、Western blot等方法分析α-SYN和TH的表达以及两者之间的关系。通过绘制生长曲线和MTT测试细胞氧化还原活性,观察α—SYN基因转染细胞的生长和损伤情况。结果 α-SYN过表达明显抑制MES 23.5多巴胺能神经元的TH表达,但对该细胞的生长和增殖无明显影响,也不引起该细胞损伤。结论 α-SYN过表达对多巴胺能神经元的TH表达具有抑制作用。  相似文献   
126.
Previous studies have shown that the mRNA of cyclic-nucleotide-gated nonselective cation (CNG) channels is expressed in rat airway epithelia and that these channels contribute to sodium-mediated short-circuit currents in cultured rat tracheal epithelia. Patch-clamp studies from human A549 cells indicate that these channels contribute to cGMP-stimulated L-cis-diltiazem- and dichlorobenzamil-inhibited whole-cell sodium currents. This study demonstrates that mRNA for primary and secondary subunits of CNG channels, halphaCNG1 and hbetaCNG1 respectively, are expressed in several human airway cell lines, including normal and cystic fibrosis bronchial airway cells, in normal and cystic fibrosis tracheal airway cell lines and nasal polyp tissue from a cystic fibrosis patient. The mRNA of ralphaCNG1 in rat lung increased in response to increased circulating glucocorticoids and decreased in animals with lowered circulating glucocorticoids after aminoglutethimide treatment. Likewise the mRNA of halphaCNG1 increased in the presence of glucocorticoids in cultured alveolar airway cells. The mRNA of alphaCNG1 in rat lung was also increased in response to a low-salt diet and lowered in animals fed a high-salt diet. Likewise the mRNA of alphaCNG1 was increased in response to increased aldosterone and decreased in animals given spironolactone. These results suggest that mRNA for alphaCNG1 increases in response to elevated glucocorticoids or mineralocorticoids. Because alphaCNG1 is a functional sodium entry channel in both rat and human airway epithelial cells, if channel protein is also elevated this channel could mediate an increase in sodium absorption across lung epithelia in response to circulating hormones.  相似文献   
127.
We investigated effects of sleep on pain-related somatosensory evoked potentials (SEP) following painful electrical stimulation of the left index finger. The biggest advantage of this method is that signals ascending through both A-beta fibers relating to touch and A-delta fibers relating to pain can be recorded simultaneously. While the subject was awake, non-painful stimulation evoked early- and middle latency components, N20, P30 and N60, at the C4 electrode, and painful stimulation evoked not only early- and middle latency components at the C4 but also later pain-specific components, N130 and P240, at the Cz electrode. During sleep, N20 and P30 did not show a significant change in amplitude, N60 showed a slight but significant amplitude reduction, and N130 and P240 significantly decreased in amplitude or disappeared, as compared with those while awake. Therefore, we speculate on the mechanisms generating each component as follows; (1) N20 and P30 are the primary components generated in SI ascending through A-beta fibers. (2) N60 is the secondary component generated in SI involving cognitive function to some degree. (3) N130-P240 are the pain-specific components ascending through A-delta fibers, and closely related to cognitive function, because they were much affected by consciousness, different from the components ascending through A-beta fibers.  相似文献   
128.
Adenoid cystic carcinoma of the lower respiratory tract is an uncommon tumor that can arise in the mainstem bronchus and often presents as an endobronchial mass lesion causing bronchial obstruction with post obstructive atelectasis and pneumonia. Exfoliative cytology is seldom useful in the diagnosis of primary bronchial adenoid cystic carcinoma, because these neoplasms usually have a submucosal location with often intact mucosa. Since most endobronchial adenoid cystic carcinomas are endoscopically visible, bronchoscope-guided fine-needle aspiration constitutes an excellent approach to establish a pathologic diagnosis. The fine-needle aspiration cytology of primary pulmonary adenoid cystic carcinoma has been rarely described. We report a case of primary adenoid cystic carcinoma of the lung having characteristic cytologic features and correlate with computed tomography, bronchoscopic, and histological findings. Bronchoscope-guided aspiration cytology provided a conclusive diagnosis of adenoid cystic carcinoma, which was further corroborated by histology in the pneumonectomy specimen. Diagn. Cytopathol. 2004;30:51-56.  相似文献   
129.
河南省幼师学生心理健康状况调查分析   总被引:6,自引:0,他引:6  
目的 了解河南省幼师学生的心理健康状况,为提高幼师的心理素质提供依据。方法 对来自河南南阳一师,洛阳一师,郑州幼师3所学校的580名幼师女生进行症状自评量表(SCL-90)测定。数据经t检验,q检验和卡方检验。结果 幼师在校生中有63.81%学生存在心理健康问题。11.43%学生有明显心理障碍,突出表现为强迫,人际敏感,偏执,敌对,抑郁,不同年级学生心理健康状况存在明显差异。结论 提示幼师学生存在不同程度心理健康问题。学校心理卫生和教育工作者必须予以重视,进行干预。  相似文献   
130.
人白细胞介素18(hIL-18)的纯化及生物学活性的鉴定   总被引:1,自引:1,他引:1  
目的:在大肠杆菌中高效表达重组人IL-18(rhIL-18)蛋白,制备具有高纯度、高活性的rhIL-18。方法:用IFTG诱导重组蛋白表达载体pKK223-3/hIL-18进行蛋白表达;菌体经超声破碎分离包含体,并对包含体进行洗涤、变性和复性处理,用DEAE-Sepharose CL-6B阴离子交换柱纯化复性的rhIL-18;以人外周血单核淋巴细胞,通过T细胞增殖实验、^125I-UdR标记的细胞毒实验、ELISA方法检测细胞因子的产生量等方法,测定rhIL-18的生物学活性。结果:在大肠杆菌中成功地诱导、表达了rhIL-18,SDS-PAGE凝胶电泳分离显示在分子量大约18.3kD处有一诱导蛋白带,Western blot证明表达产物与抗IL-18单克隆抗体有特异性免疫反应;表达产物经纯化后纯度达94%;表达的rhIL-18蛋白具有促进T细胞增殖、增强NK细胞细胞毒作用及诱导外周血单核淋巴细胞合成IFN-γ的能力,基本上具有天然IL-18相同的生物学活性。结论:为rhIL-18的获得及为进一步研究其生物学功能提供了一定的条件,并为将rhIL-18用于肿瘤的免疫生物治疗奠定了基础。  相似文献   
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