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41.
研究生科学道德和学风建设是学位与研究生教育的重要组成部分。针对近年来科学研究和学术活动中各种违背科学道德和学术规范的行为时有发生,国家教育部对研究生科学道德和学风建设日益重视,因此构建研究生的科学道德和学风教育质量管理体系具有十分重要的意义。实现研究生科学道德和学风教育质量体系的方针和目标需具备三个要素,即教育实践的模式(集主题教育、方法学习、学术实践三位一体)、有效性评价机制和绩效考核机制。此外,尚需建立体系优化机制,以适应各种内外部因素的变化,保持体系的更新和优化。 相似文献
42.
目的: 探讨非活动性结核性胸膜炎与活动性结核性胸膜炎CT扫描影像表现。方法: 对2012年6月1日至2021年3月30日在首都医科大学附属北京胸科医院就诊的单纯非活动性结核性胸膜炎患者68例和同期活动性结核性胸膜炎44例的CT扫描影像表现进行比较。结果: (1) 68例非活动性结核性胸膜炎患者 CT扫描影像表现中胸膜粘连62例(91.2%),胸膜有钙化者28例(41.2%),叶间裂受累22例(32.4%),胸腔积液12例(17.6%),包裹性胸腔积液8例(11.8%)。(2)44例活动性结核性胸膜炎患者CT扫描影像表现中胸膜粘连30例(68.2%),未见胸膜钙化,叶间裂受累32例(72.7%),胸腔积液43例(97.7%),包裹性胸腔积液26例(59.1%)。(3)非活动性与活动性结核性胸膜炎CT扫描影像比较:胸膜粘连、胸膜钙化发生率高,差异均有统计学意义(χ2=9.630,P=0.002;χ2=23.737,P=0.000);叶间裂受累、胸腔积液、包裹性胸腔积液的发生率低,差异均有统计学意义(χ2=12.692,P=0.000;χ2=68.548,P=0.000;χ2=28.301,P=0.000)。结论: 非活动性结核性胸膜炎的CT扫描影像与活动性结核性胸膜炎比较胸膜粘连、胸膜钙化的发生率高,胸腔积液、包裹性胸腔积液、叶间裂受累的发生率低。识别非活动性和活动性结核性胸膜炎的CT扫描影像特点,对患者临床治疗有指导意义。 相似文献
43.
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
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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
46.
Objective To investigate the relationship between degree of endometrioma adhesions and clinical feature, surgical treatment and postoperative recurrence. Methods From Jan 2003 to Mar 2008, 662 patients with endometrioma undergoing laparoscopic ovarian endometrioma excision in Peking Union Medical College Hospital were studied retrospectively. All patients were classified into four groups according to the extent of adhesions: 31 cases in none adhesions group, 123 cases in mild adhesions group (filmy thickness, avascular, easily separated adhesions), 310 cases in moderate adhesions group (less than a half of ovary was adjacent to dense thickness adhesions which was difficult to separate, or above a half of ovary were adjacent to filmy thickness adhesions) and 198 cases in severe adhesions group (above a half of ovary was adjacent to dense thickness, well vascularized adhesions which was difficult to separate, and always involved the other pelvic organs, observed angiogenesis). The comparison of degree, characteristics, period of pain, lab test, surgical management and postoperative recurrence was performed among those above groups. In the mean time, risk factors and multinomial logistic regression were analyzed. Results (1)Clinical characteristics: The incidence of patients with dysmenorrhea, dyspareunia, straining feeling in anus, chronic pelvic pain and the level of CA125 (>35 kU/L) was remarkably higher in moderate-to-severe adhesion groups than in none-to-mild adhesions groups (P=0.000, 0.000, 0.001, 0.006 and 0.000, respectively). Infertility rate were significantly higher in severe adhesions group(15.7%,31/198) than none adhesions group(3.2%,1/31), mild adhesions group(11.4%,14/123) and moderate adhesions group(9.7%,30/310, OR=1.728, P<0.05).(2)Operating time and blood loss: Operating time of each groups was as followed: (37±15) min in none adhesions group, (42±19) min in mild adhesions group, (50±20) min in moderate adhesions group and (63±22) min in severe adhesion group. Blood loss was (23±12) ml in none adhesion group, (31±27) ml in mild adhesion group, (40±32) ml in moderate adhesion group and (70±67) ml in severe adhesions group. Thicker adhesions result in longer operation time and more blood loss. (3)Combined with other disease: The ratio of patients who combined with adenomyosis or deeply infiltrating endometriosis in moderate-to-severer adhesion groups was higher than patients in none-to-mild adhesions groups (OR=3.466, P=0.000). (4) Postoperative recurrence: It was categorized into recurrence of pain and cyst. Moderate-to-severe adhesions was related to higher recurrence rate of pain (OR=1.685,P=0.046), but was irrelevant to recurrence of cyst. Conclusion The more extent of endometrioma adhesions was related to severer pelvic pain symptoms, longer operating time and more blood loss. Postoperative pain recurrence rate was observed in moderate-to-severe adhesion group. Extent of adhesions was irrelevant to cyst recurrence. 相似文献
47.
通过分析中国马拉松运动员ACE基因I/D多态频率分布特征,探讨其作为杰出耐力基因标记的可行性。选择我国马拉松健将、国际健将级运动员26名作为马拉松运动员组,汉族学生216名作为对照组。对两组受试者进行ACE基因I/D多态性测定。结果显示:我国马拉松运动员组的等位基因频率和基因型频率与对照组比较无显著差异,其中15名国际健将中无一DD型纯合子,提示我国优秀马拉松运动员的纯合子DD型频率低下是其ACE基因多态频率分布的主要特征。 相似文献
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目的 探讨肺上沟癌的临床特点及放疗疗效和不良反应。方法 回顾性分析 3 3例肺上沟癌住院病人的临床特征和常规放疗的疗效。结果 肺上沟癌占原发性支气管肺癌的 2 9% ,常见症状为 :患侧肩、背和上肢疼痛 ( 78 8% ) ,后 1,2 ,3肋骨或椎骨破坏( 5 7 6% ) ,Horner’s综合征 ( 3 6 7% ) ;少见的症状为 :咳嗽 ( 2 7% ) ,咯血 ( 9% ) ;中位生存期为 8 4月 ;1,3 ,5年生存率分别为 3 5 6% ,12 3 % ,4 6% ;放疗反应可耐受。结论 肺上沟癌相当少见 ,其临床特征基本符合pancoast综合症 ,本病预后差 ,但放疗可缓解疼痛 ,提高生存质量。 相似文献