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目的:为了解心理应激对免疫功能的影响,对影响免疫功能的多种心理应激动物模型进行比较分析,以寻找合理可行的慢性情绪应激动物模型.方法:实验于2004-09/10在江西师范大学体育学院运动生理实验室完成,动物实验方法符合动物伦理学要求.①实验材料及分组:选用雄性SD大鼠32只,按随机数字表法分为4组(n=8),即对照组、空瓶组、束缚组及灯光加电击组.②实验方法:对照组大鼠正常饲养,其余各组建立相应的心理应激刺激模型.各组大鼠在正式实验之前适应性生活1周,不同强度情绪刺激为期2周.③实验评估:实验期间观察各组大鼠体质量变化.情绪应激后24 h应用放免法测定白细胞介素2、白细胞介素6含量,应用脲酶-Berthelot比色法测定血尿素氮含量.结果:32只大鼠全部进入结果分析.①实验期间各组大鼠体质量呈上升趋势,实验结束时,空瓶组大鼠体质量低于对照组(P<0.05).②各组大鼠的白细胞介素2、白细胞介素6含量差异无显著性意义(P>0.05).与对照组比较,空瓶组、束缚组白细胞介素2含量有下降趋势,白细胞介素6含量有上升趋势.③空瓶组大鼠血尿素氮含量显著高于对照组(P<0.01),其他各组差异无显著性意义(P>0.05).结论:体质量和血尿素氮是心理应激较为敏感的指标.空瓶、束缚及灯光加电击3种心理应激模型比较,空瓶刺激效果较好.  相似文献   
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目的:利用核因子κBp65特异性小干涉核糖核酸抑制肿瘤坏死因子α诱导的关节滑膜细胞中一氧化氮合酶2和环氧合酶2的表达,探讨基因治疗类风湿性关节炎的新方法。方法:实验于2005-03/2006-03在北京大学医学部中心实验室(国家级)完成。①实验材料:清洁级健康近交系SD大鼠10只;一氧化氮合酶2,环氧合酶2,3-磷酸甘油醛脱氢酶引物(由北京奥科生物公司合成);肿瘤坏死因子α(Sigma公司);核因子κBp65特异性小干涉核糖核酸和转染条件由北京大学运动医学研究所陈连旭博士提供。②实验干预:切取大鼠髋关节和膝关节的滑膜体外培养滑膜细胞。利用脂质体siPORTTMLipid将核因子κBp65特异性小干涉核糖核酸转染滑膜细胞,再加入肿瘤坏死因子α刺激。阴性对照为任意编码的小干涉核糖核酸,阳性对照为针对3-磷酸甘油醛脱氢酶的小干涉核糖核酸。③实验评估:提取滑膜细胞中的核蛋白,利用电泳迁移率试验检测核因子κB的活性;提取滑膜细胞的核糖核酸和总蛋白,利用反转录聚合酶链反应和蛋白质免疫印记法从信使核糖核酸和蛋白质两水平检测一氧化氮合酶2和环氧合酶2的表达。结果:①肿瘤坏死因子α和核因子κBp65特异性小干涉核糖核酸对核因子κB转录活性的影响:与正常滑膜细胞相比,肿瘤坏死因子α可以显著提高核因子κB的结合能力,而事先转染小干涉核糖核酸48h,再用肿瘤坏死因子α刺激,核因子κB的结合能力又显著降低。②核因子κBp65特异性小干涉核糖核酸对核因子κB下游因子的影响:在培养的滑膜细胞中,肿瘤坏死因子α可以显著增加一氧化氮合酶2和环氧合酶2的表达;在转染小干涉核糖核酸抑制核因子κBp65的表达后再用肿瘤坏死因子α刺激,一氧化氮合酶2和环氧合酶2的表达被抑制。结论:①核因子κBp65特异性小干涉核糖核酸可降低肿瘤坏死因子α诱导的滑膜细胞中核因子κB的转录活性,抑制其下游因子一氧化氮合酶2和环氧合酶2的表达。②核因子κBp65特异性小干涉核糖核酸可用于基因治疗类风湿性关节炎的试验研究。  相似文献   
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目的:评价抗角蛋白抗体、抗核周因子和抗环瓜氨酸肽抗体联合检测在幼年类风湿关节炎诊断及病情评估中的意义。方法:①观察对象及分组:选择2003-01/2005-12首都医科大学附属北京儿童医院风湿免疫病房住院治疗的76例幼年类风湿关节炎患儿及54例非幼年类风湿关节炎患儿,正常对照30例(家属均知情同意)。②检测上述人员血清抗角蛋白抗体、抗核周因子抗体和抗环瓜氨酸肽抗体水平;观察两组患儿出现临床症状、体征例数及实验室检测数据。③对幼年类风湿关节炎诊断的敏感性、特异性,阳性似然比、阴性似然比进行评价,并对幼年类风湿关节炎患儿中3种抗体联合检测阳性组阴性组的临床症状、体征及实验室检查方面的指标进行比较,资料作统计学分析。结果:两组患儿130例,正常儿童30例,全部进入结果分析。①两组患儿临床症状、体征例数及实验室检测值差异没有显著性意义。②抗角蛋白抗体、抗核周因子抗体和抗环瓜氨酸肽抗体联合检测对幼年类风湿关节炎组早期诊断缺乏有效性。③抗角蛋白抗体( )/抗核周因子抗体( )/抗环瓜氨酸肽抗体( )病例与抗角蛋白抗体(-)/抗核周因子抗体(-)/抗环瓜氨酸肽抗体(-)病例相比,关节强直病例明显增多,差异有显著性(较正χ2=3.902,P=0.048),抗链球菌溶血素“O”和C-反应蛋白均显著增高,差异有显著性(χ2=2.616,3.557,P=0.025,0.001)。结论:抗角蛋白抗体、抗核周因子抗体、抗环瓜氨酸肽抗体联合检测对幼年类风湿关节炎缺乏早期诊断意义及特异性,联合检测对判断疾病的活动性、病理损害程度和预后有临床意义。  相似文献   
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The purpose of this work was to investigate the volumetric bone mineral density (vBMD), bone microstructure, and mechanical indices of the distal radius in female patients with rheumatoid arthritis (RA). We report a cross‐sectional study of 66 middle‐aged female RA patients and 66 age‐matched healthy females. Areal BMD (aBMD) of the hip, lumbar spine, and distal radius was measured by dual‐energy X‐ray absorptiometry (DXA). High‐resolution peripheral quantitative computed tomography (HR‐pQCT) was performed at the distal radius, yielding vBMD, bone microstructure, and mechanical indices. Cortical and trabecular vBMD were 3.5% and 10.7% lower, respectively, in RA patients than controls, despite comparable aBMD. Trabecular microstructural indices were –5.7% to –23.1% inferior, respectively, in RA patients compared to controls, with significant differences in trabecular bone volume fraction, separation, inhomogeneity, and structural model index. Cortical porosity volume and percentage were 128% and 93% higher, respectively, in RA patients, with stress being distributed more unevenly. Fourteen RA patients had exaggerated periosteal bone apposition primarily affecting the ulnovolar aspect of the distal radius. These particular patients were more likely to have chronic and severe disease and coexisting wrist deformity. The majority of the differences in density and microstructure between RA patients and controls did not depend on menstrual status. Recent exposure to glucocorticoids did not significantly affect bone density and microstructure. HR‐pQCT provides new insight into inflammation‐associated bone fragility in RA. It detects differences in vBMD, bone microstructure, and mechanical indices that are not captured by DXA. At the distal radius, deterioration in density and microstructure in RA patients involved both cortical and trabecular compartments. Excessive bone resorption appears to affect cortical more than trabecular bone at distal radius, particularly manifested as increased cortical porosity. Ulnovolar periosteal apposition of the distal radius is a feature of chronic, severe RA with wrist deformity. © 2013 American Society for Bone and Mineral Research.  相似文献   
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Background and Aims: In the management of peptic ulcer bleeding, the benefits of second‐look endoscopic treatment with thermal coagulation or injections in controlling recurrent bleeding is unsure. This study set out to compare efficacy of routine second‐look endoscopy with treatment using either thermal coagulation or injections versus single endoscopy by pooling data from published work. Methods: Full publications in the English‐language published work as well as abstracts in major international conferences were searched over the past 10 years, and six trials fulfilling the search criteria were found. Outcome measurements included: (i) recurrent bleeding; (ii) requirement of surgical intervention; and (iii) mortality. We examined heterogeneity of trials and pooled the effects by meta‐analysis. The quality of studies was graded according to the prospective randomization, methods of patient allocation, the list of exclusion criteria, outcome definitions and the predefined salvage procedures for uncontrolled bleeding. Results: Among 998 patients recruited in these five randomized trials, 119 received routine second‐look endoscopy with thermal coagulation, and 374 received second‐look with endoscopic injection and 505 had single endoscopic therapy. Less recurrent bleeding was reported after thermal coagulation (4.2%) than single endoscopy (15.7%) (relative risk [RR] = 0.29; 95% confidence interval [CI] = 0.11–0.73), but no reduction was reported for the requirement of surgical intervention and all‐cause mortality. Injection therapy did not reduce re‐bleeding (17.6%) when compared to single endoscopy (20.8%; RR = 0.85; 95% CI = 0.63–1.14), requirement for surgery and mortality. Conclusion: Routine second‐look endoscopy with thermal coagulation, but not injection therapy, reduced recurrent peptic ulcer bleeding. There is no proven benefit in reducing surgical intervention and overall mortality.  相似文献   
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Aims. This article aims to review the literature published to date on the types, current use, the biomechanical effects and adverse effects of maternity support belts for low back pain during pregnancy, to identify future research directions. Background. Lumbar/pelvic support belts are frequently recommended for the prevention and treatment of low back pain during pregnancy. Design. Systematic review. Methods. MEDLINE, CINAHL, the Cochrane Library and patents databases were electronically searched. Results. Maternity support belts belong to one of the four main types of maternity support garments, which are widely commercially‐available. Current research showed limited evidence in support of the commercial maternity products regarding the effectiveness in the prevention and/or treatment of low back pain during pregnancy, other than that from the manufacturers. However, potential stabilisation effect of maternity support belt was demonstrated in some studies. Adverse effects reported include increased pain, fetal heart rate changes, skin irritation and discomfort. Conclusions. There is insufficient scientific evidence to conclude that wearing maternity support belts reduces pregnancy‐related low back pain and/or pelvic girdle pain. Future research directions in the area of biomechanics and physiology are recommended. Relevance to clinical practice. This review provides comprehensive understanding of the effectiveness of maternity support belts for the relief of low back pain during pregnancy which will facilitate healthcare professionals in providing evidence‐based advice to their patients.  相似文献   
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青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究   总被引:1,自引:0,他引:1  
赵凯存  宣文漪  赵一  宋振玉 《药学学报》1989,24(11):813-816
将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5~4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。  相似文献   
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