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101.
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103.
目的 克隆土耳其斯坦东毕吸虫磷酸丙糖异构酶的全长基因。方法 根据日本血吸虫和曼氏血吸虫磷酸丙糖异构酶基因的保守区设计引物,利用RT—PCR扩增出土耳其斯坦东毕吸虫磷酸丙糖异构酶基闪的大片段,再结合RACE技术分别得到磷酸丙糖异构酶基因的3’端和5’端,将3部分序列拼接后获得磷酸丙糖异构酶基因全长cDNA序列,并提交GenBank。结果 成功克隆了土耳其斯坦东毕吸虫磷酸丙糖异构酶基因全长cDNA序列并提交GenBank,登录号为DQ092331。结论 土耳其斯坦东毕吸虫磷酸丙糖异构酶基因全长cDNA的克隆为进一步表达及其生物学性能的分析提供了理论基础。 相似文献
104.
OBJECTIVES: To assess the effectiveness and safety of additional bedtime H2‐receptor antagonists (H2RAs) in suppressing nocturnal gastric acid breakthrough (NAB) via a systematic review. METHODS: Eligible trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 2, 2004), MEDLINE (January 1966–June 2004), EMBASE (January 1980–June 2004) and CINAHL (January 1982–June 2004). Additional hand‐searching was conducted on the proceedings of correlated conferences, eight important Chinese journals and references of all included trials. All randomized controlled trials evaluating H2RAs for the control of NAB were eligible for inclusion. The systematic review was conducted using methods recommended by The Cochrane Collaboration. RESULTS: Only two randomized crossover studies, comprising 32 participants, met the inclusion criteria. Because the design, dosage and duration of the treatments were different between the studies, it was not possible to conduct meta‐analysis. There were no consistent conclusions found between the two included studies in evaluating H2RAs for the control of NAB. CONCLUSIONS: No implications for practice at this stage can be concluded. Appropriately designed large‐scale randomized controlled trials with long‐term follow up are needed to determine the effects of additional bedtime H2RAs in suppressing NAB. 相似文献
105.
目的 研究模拟舰船两种剂量水平磁场复合噪声、高温对机体联合作用的特点。方法 采用有交互作用的三因素二水平的正交试验设计方法及方差分析法,按正交表L8(2^7)的要求安排8种复合暴露剂量组合,分别将兔和大鼠分为8个复合暴露组和8个对照组。结果 兔球结膜毛细血管管径、大鼠肝和脾脏HSP70的分析结果显示出磁场是对其影响的主因素(均为P〈0.01),其次是高温(均为P〈0.05),大鼠下丘脑AVP和大鼠脑组织HSP70的分析结果显示出磁场是对其影响的主因素(均为P〈0.05)。兔血浆内皮素的分析结果显示出磁场与噪声交互作用所对应的F值有非常显著性意义(P〈0.01),磁场与噪声、高温三者之间交互作用所对应的F值也有显著性意义(P〈0.05)。结论 磁场是对上述指标影响的主因素,而高温也是重要因素;磁场与噪声有交互作用,磁场与噪声、高温三者之间也有交互作用;应该重视舰船环境因素对舰船人员的复合作用。 相似文献
106.
Joseph Biederman Haitao Gao Ann K Rogers Thomas J Spencer 《Neuropsychopharmacology》2006,60(10):1106-1110
BACKGROUND: The validity of parent reports regarding children's attention-deficit/hyperactivity disorder (ADHD) symptoms has been questioned. This study assessed whether parent reports were as sensitive as teacher reports to document change in ADHD symptoms during clinical trials with atomoxetine. METHODS: Data were compared from two randomized, double-blind, placebo-controlled clinical trials of atomoxetine using different versions (parent or teacher) of the same rating scale (Attention-Deficit/Hyperactivity Disorder Rating Scale-IV [parent or teacher] Version: Investigator Administered and Scored - ADHD RS). Exclusion criteria included history of bipolar disorder, psychosis, seizures, alcohol abuse, or positive drug screen. Patients (6-16 years old) were treated with atomoxetine (titrated to a maximum dose of 1.8 mg/kg/day) administered once daily for up to 7 weeks. Parent and teacher ratings were compared using an analysis of covariance (ANCOVA) model. RESULTS: The analysis (n = 318) showed that treatment effects (mean change, baseline to endpoint) were similar between parent and teacher ratings (total, p = .762; inattention, p = .519; hyperactive/impulsive, p = .955). Effect sizes also were similar based on total scores (parent ratings = .69; teacher ratings = .63). CONCLUSIONS: Parent reports are as sensitive as teacher reports in assessing the efficacy of long-acting pharmacologic treatment for ADHD in children during clinical trials using the nonstimulant atomoxetine. 相似文献
107.
108.
Sergue? O Fetissov Jarmila Hallman Ida Nilsson Ann-Kari Lefvert Lars Oreland Tomas H?kfelt 《Neuropsychopharmacology》2006,60(8):799-802
BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones. 相似文献
109.
目的探讨物理性刺激对骨膜软骨生成方面的影响,以期培养出一种与正常关节软骨更相似的软骨组织。方法从新西兰大白兔胫骨近端内侧取下骨膜,将骨膜固定在支架上,然后将细胞支架悬吊在旋转瓶内,用水流产生的剪切应力去刺激骨膜。通过宏观观察、体积大小测量、组织切片染色与细胞外基质(ECM)成分的比较及生物力学测试分析软骨体外生长的最佳环境。结果宏观观察发现软骨生长的方向与水流的方向相同。组织切片染色可见有两层不同形态的软骨细胞和不同密度的ECM,免疫组织化学染色见在剪切应力的刺激下,软骨表面可分泌浅层蛋白质及润滑剂,且在不同大小的剪切应力刺激时,软骨表面还会产生不同厚度的表层。结论剪切应力刺激能使骨膜上的干细胞分化形成软骨,同时证明力学环境不仅影响细胞的分化与生长,而且影响细胞的形态与ECM的分泌。 相似文献
110.
Anne Pavy-Le Traon Richard L Hughson Claire Thalamas Monique Galitsky Nelly Fabre Olivier Rascol Jean-Michel Senard 《Movement disorders》2006,21(12):2122-2126
Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA. 相似文献