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11.
Gradient of alarm substance in the forced swimming test   总被引:5,自引:1,他引:4  
Three studies were conducted with rats to study the effects of a proposed alarm substance released during the forced swimming test. In the first study, rats were retested in water previously swum in but which had been subsequently diluted to varying degrees. When water was diluted by more than 25% the proposed alarm substance could no longer be detected. In the second study, rats were retested at various times after initial testing. This study showed that the alarm substance was still active by eight days after it had been initially released. The final study tested animals to see if the alarm substance could be depleted by repeated testing. Testing animals for more than an hour did not result in depletion of the alarm substance. These three studies suggest that the proposed alarm substance secreted by rats during the forced swimming test has considerable biological significance.  相似文献   
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Summary A disease-oriented approach to the discovery of novel platinum anticancer drugs has been established through the setting up of parallel human ovarian-carcinoma cell lines and xenografts. The correlation between in vitro and in vivo antitumour activity was determined for four reference platinum agents (cisplatin, carboplatin, iproplatin and tetraplatin) in eight companion lines. Two methods of assessing antitumour effect were used in vitro (tritiated thymidine incorporation and sulforhodamine B staining) and three were applied in vivo [28-day treated/control (T/C) ratio, growth delay and specific growth delay]. In vitro, large differences in cytotoxicity across the cell lines were observed for each drug. This was also reflected in the xenografts for cisplatin and carboplatin and, to a lesser extent, for iproplatin. A correlation analysis of in vitro vs in vivo data revealed a high, statistically significant positive correlation for cisplatin and a strong positive correlation for carboplatin. However, for the two platinum(IV) drugs, the correlation was less good. In particular, tetraplatin was markedly less active in vivo (showing a general lack of activity against all of the tumour lines) than its in vitro potency against the cell lines predieted, resulting in poor correlation coefficients. These human tumour panels may be valuable for the elucidation of both cellular/molecular and corresponding in vivo pharmacological mechanisms of platinum drug resistance. Moreover, the HX/62 and SKOV-3 tumour lines, which exhibit a level of intrinsic resistance to the four reference agents both in vitro and in vivo (and which were derived from patients who had not received prior platinum therapy), represent particularly useful evaluation models for the discovery of novel broad-spectrum platinum drugs.This study was supported by grants to the Institute of Cancer Research from the Cancer Research Campaign and the Medical Research Council, the Johnson Matthey Technology Centre and Bristol Myers Squibb Oncology  相似文献   
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Where treatment options are limited, the role of clinical consultation in providing information and support becomes more important. This study examines the immediate impact of medical consultation on male sub-fertility clinic attender's anxiety, depression, self-blame, information appraisal and perceptions of future fertility. Data were collected pre- and immediately post-consultation. Clinical information and consultation details were recorded. Results showed that anxiety levels were high before consultation. Following consultation anxiety and self-blame were both reduced while depression increased. Despite information about poor prognosis being given during consultation, participants remained overly optimistic about their chances of achieving a pregnancy. It appears that the consultation has a distinct psychological impact and possible mechanisms underlying this are discussed.  相似文献   
14.
This paper examines whether American males with a high degree of control over their work situation pursue healthy lifestyles and rate their physical health more positively than those who score low on occupational self-direction. That is, are persons who control their work more likely to also try to control their health through living in a particularly healthy manner? We found that there was no support for a spillover effect from high occupational self-direction to enhanced participation in health lifestyles or more positive self-rated health. The findings suggest health lifestyles have spread throughout occupational work groups in the U.S. and support research that maintains such lifestyles have spread across social strata in America.  相似文献   
15.
INTRODUCTION: Very little is known about clinical nurse specialists and nurse practitioners (advance practice nurses [APNs]) who practice in emergency care settings. The Advanced Practice Committee of the ENA sought to determine a profile of these individuals. METHODS: Surveys were distributed to all registrants at 2 ENA conferences and posted on the ENA Web site. This survey asked 17 questions concerning the demographic characteristics of the APN respondents (eg, education, experience, certification, state recognition, and practice area). The survey was completed by 166 APNs. RESULTS: APNs had considerable experience as ED registered nurses before becoming an APN. They obtained their APN education at the master's degree or post-master's degree level. State recognition was required for 89.2% of the APNs. The majority of APNs (61.4%) obtained their certification through the American Nurses Credentialing Center. Nurse practitioners were predominantly family nurse practitioners (43%), and clinical nurse specialists were either critical care clinical nurse specialists (8.9%) or had other certifications (5.9%). APNs provided services in both the main emergency department and the fast track (45.7%) and were relatively new to their role as an APN. DISCUSSION: Consistent with current educational and certification requirements, the vast majority of APNs held a master's degree. Although relatively new to their role as APNs in emergency care, they were nonetheless very experienced as ED registered nurses. The majority of APNs were certified, even though that is not required for practice in all states. Continued research is needed to identify the most effective utilization of APNs, document their contributions to patient care outcomes, and develop strategies to meet their educational and practice needs.  相似文献   
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The peripheral vascular response to Escherichia coli endotoxin (1 mg/kg/i.v.) was measured for 2 hr in the pentobarbital anesthetized dog. Total venous return was collected and returned by a pump to the right atrium to maintain a constant cardiac output. Occlusion of the venous lines permitted estimation of venous compliance in the systems drained by the superior (SVC) and inferior vena cavae (IVC). After endotoxin administration, arterial pressure and total peripheral resistance rapidly dropped and remained low for 2 hr. IVC compliance was decreased at 10-30 min and SVC compliance at 10 min after endotoxin. The decrease in compliance is interpreted as venous dilation and probably venous pooling. The latter may account for a substantial portion of the total venous pooling reported in early endotoxin shock. After 30 min, compliance increased and by 60 min was equal to control. Left ventricular relaxation ability decreased as indicated by maximal negative dp/dt. Ibuprofen, 10 mg/kg, was administered at 120 min or earlier, depending on the state of the animal; rapid recovery of arterial pressure and ventricular function occurred without a significant change in venous compliance.  相似文献   
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A case is described in which a patient, who initially presented with five separate bladder calculi, was found to have had coalescence of three calculi to produce a large stone. This may be one mechanism in the development of a giant vesical calculus.  相似文献   
20.
Abel Garcia-Garcia 《Journal of oral and maxillofacial surgery》2005,63(5):723; author reply 723-723; author reply 724
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