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61.
Purpose and Methods: We performed multiple comparisons between available amino acid (aa) sequences of homeodomain(HOM)-containing proteins from a wide spectrum of animals to create an evolutionary classification of the proteins. Results: Based on results of statistical and special computational analyses of over 500 homeodomain aa sequences (HOMs) a novel system of concepts describing complex structural correlations between homologous proteins is proposed. This system includes such notions as differentiated isofunctionality of aa, chemotype, stereotype, local functional motifs, gradual conservativeness of aa positions, and group-specific domain patterns, as well as major categories of the evolutionary classification of HOMs (Division, Type, Branch, Class, Family, Series, Variety, Sort). Using this approach, a complete structural systematics of HOMs belonging to proteomes of eukaryotic animals is proposed. Conclusions: The proposed structural classification of HOMs is in full agreement with the bulk of experimental data revealing complex functional similarities and differences among HOMs in terms of their expression patterns in developing embryos. It turn, this classification can provide answers regarding homology among homeodomains when experimental data are conflicting.  相似文献   
62.
School violence in rural communities has gained considerable attention nationally. Examined are theoretical considerations involving escape theory, the risk and protective factors for school violence, case analyses of recent case studies, and discussion of recent school violence involving fatal injuries to others. Also discussed are diagnostic issues in understanding children who are at-risk for school violence and ways school violence maybe managed in the schools. Suggestions and recommendations including recommendations provided by the National School Safety Center for school personnel are offered, as are steps to be taken in creating a safe school environment. This information may be helpful to child psychiatry and clinical personnel who provide services to school aged children.  相似文献   
63.
BACKGROUND: So far there are three different scores to predict postoperative vomiting (PV: Apfel et al., 1998) or postoperative nausea and vomiting (PONV: Koivuranta et al., 1997; Palazzo and Evans, 1993). All three scores used logistic regression analysis to identify and create weights for the risk factors for PV or PONV. In short, these were sex, age, history of previous PONV, motion sickness, duration of anaesthesia, and use of postoperative opioids. However, an external evaluation and a comparison of these scores has not been performed so far. METHODS: Patients undergoing a variety of surgical procedures under general anaesthesia were studied prospectively. Preoperatively, they completed a questionnaire concerning potential risk factors for the occurrence of PV or PONV implemented in the three risk scores. Balanced anaesthesia (induction agent, nondepolarising neuromuscular blocker, opioid, and inhalation agent in nitrous oxide/oxygen) was performed. No intravenous anaesthesia or any antiemetic prophylaxis was applied. Postoperatively, the patients were observed in the recovery room for the occurrence of PV and PONV and were visited twice on the ward within the 24-h observation period. Both the patients and the nursing staff were asked whether PV or PONV was present. The severity of PONV was categorised using a standardised scoring algorithm. A total of 1,444 patients was finally included into the analysis. Using information of the predicted risk for the individual patients and the actual occurrence of PV or PONV, Receiver Operator Characteristics (ROC-curves) were drawn. The area under each ROC-curve was calculated as a means of the predictive properties of each score and was compared for statistical differences. RESULTS: For prediction of PONV (any severity) the AUC-values (AUC=area under the curve) and the corresponding 95%-confidence intervals were: Apfel: 0.70 (0.67-0.72); Koivuranta: 0.71 (0.69-0.73); Palazzo: 0.68 (0.65-0.70). For prediction of PV: Apfel: 0.73 (0.71-0.75); Koivuranta: 0.73 (0.70-0.75); Palazzo: 0.68 (0.65-0.70). Thus, all three scores appeared to have a moderate accuracy as measured by the AUC. The score of Koivuranta predicts PONV (P=0.007) and also PV (P=0.002) significantly better than Palazzo's score. Furthermore, for predicting of PV the score of Apfel was also superior to Palazzo's score (P=0.005). All three scores predict PV with the same accuracy as PONV. CONCLUSION: The occurrence of PV and PONV in patients undergoing surgery under balanced anaesthesia can be predicted with moderate but acceptable accuracy using one of the available risk scores, regardless of local surgical or anaesthesiological circumstances. For clinical practice, we recommend the score published by Koivuranta, since its calculation is very simple.  相似文献   
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65.
曾毅 《安徽医学》2006,27(5):364-365
目的探讨血脂水平与脑梗死的关系。方法通过对137例急性脑梗死患者与对照组血脂变化观察,多因素分析用SPSS10.0软件包中的Logistic回归方程,计算相对危险度(RR),RR的95%可信限(CI)。结果脑梗死组TC、TG、LDL-C浓度均明显高于对照组,而HDL-C浓度明显低于对照组。结论血清TC>6.0mmol/L才增加脑梗死的风险,而HDL-C浓度≥0.85mmol/L可降低脑梗死的风险。  相似文献   
66.
付歌  顾春华  李飞 《医学教育探索》2006,(11):1318-1322
通过引入位图映射以及元组空间的概念,提出了一个数据包分类算法,该算法可以满足高性能网络对骨干路由器的要求,能够以线速完成对输入数据包的分类处理。算法在时间及空间复杂度上性能较好,并具有很好的扩展性。  相似文献   
67.
某市区儿童肥胖现状及影响因素的现况调查   总被引:6,自引:0,他引:6  
目的:了解重庆市区儿童肥胖的现状及危险因素,为家长、教育系统实施干预提供依据,以预防成年期相关疾病的发生。方法:随机抽取该地区3~16岁儿童1 867例,采用问卷方式收集资料进行现况调查,以BMI法为肥胖的诊断标准,采用国内推荐的BMI≥28.0 kg/m2将儿童分为肥胖组和正常对照组。结果:儿童肥胖的发生率为12.59%(男13.83%,女9.74%)。危险因素分析显示,有肥胖家族史、每日肉食摄入量、营养食品的添加、母乳喂养时间短、过早添加固体食物、看电视为主要危险因素,VitC是肥胖的保护因素。结论:该区儿童肥胖率明显高于历年水平,呈发展趋势,在儿童实施早期干预措施对预防青春期及成年期肥胖和其他相关疾病有重要的意义。  相似文献   
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69.
Summary When aggregating financial risk on a portfolio level, the specification of the dependence structure between the risk factors plays an important role. Promising parametric models are often based on a so-called copula approach. Case studies of market crashes suggest the application of concepts allowing for extremal dependence. We present a transformed copula as a new model that both fits the data and allows for exact prediction in the tails. It turns out that the new model improves benchmark models like the t- or Clayton copula with respect to risk measures like VaR or Expected Shortfall. By performing different goodness-of-fit tests, the quality of the estimation is examined.  相似文献   
70.
目的探讨孕妇B族溶血性链球菌(GBS)定植及其分娩早产儿的GBS感染状况,评估早产儿GBS定植的危险因素。方法采用前瞻性队列研究方法,纳入2017年1月至2018年1月分娩的859例早产孕妇作为研究对象。入院时采集孕妇阴道下段1/3和直肠拭子行GBS培养,其中515例行实时PCR GBS DNA检测。采集所纳入孕妇分娩的早产儿的口咽分泌物、胃液或血液进行GBS培养。取孕妇外周血及其分娩的早产儿脐血测定抗GBS荚膜多糖抗体水平。调查早产儿GBS感染情况和影响定植的围产因素。结果 859例孕妇阴道、直肠GBS培养阳性率为14.8%(127/859)。515例GBS DNA检测的阳性率为15.1%(78/515)。859例孕妇共分娩活产早产儿976例,其中43例(4.4%)GBS培养阳性;4例发生早发型GBS疾病,其中2例肺炎,2例早发型GBS败血症。127例GBS阳性孕妇分娩的127例早产儿中,34~<37周早产儿组GBS阳性率明显低于<34周早产儿组(P=0.013),抗GBS荚膜多糖抗体水平明显高于<34周早产儿组(P=0.001)。多因素logistic回归分析显示胎膜早破>18 h和绒毛膜羊膜炎是早产儿GBS定植的独立危险因素(分别OR=6.556、6.160,均P < 0.05)。结论早产儿GBS阳性率及抗GBS荚膜多糖抗体水平与胎龄相关。胎膜早破>18 h和绒毛膜羊膜炎可增加早产儿GBS定植的风险。  相似文献   
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