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Spontaneously hypertensive rats (SHR) overconsume NaCl compared to the normotensive Wistar Kyoto rat (WKY) rat. In the present experiment, two-bottle preference for NaCl (0.01, 0.03, 0.1, 0.3, 0.5, 1.0, 3.0 M) and lick rate analyses were used to identify the possible mechanisms that underlie the intake of NaCl by male SHR. Two-bottle preference and absolute NaCl intake by SHR were greater than that of WKY rats. When NaCl intake was calculated on the basis of body weight, SHR consumed more NaCl per 100 g body weight than did WKY. Also, during the one-bottle test, SHR consumed more 0.1 and 0.3 M NaCl per 100 g body weight than did WKY. The increased intake of NaCl by SHR was most evident for 0.3 M NaCl. Intake is determined by the initial rate of licking and the decline in lick rate over time. Nonlinear regression analysis of lick rate showed that the initial lick rates (licks/min) were similar for male WKY and SHR. Lick rate declined more rapidly when WKY rats drank 0.3 M than when they drank 0.1 M NaCl, a result consistent with the role of negative feedback in controlling the decay in lick rate. This concentration-dependent change in lick rate was not seen in SHR. Also, SHR lick rate for 0.1 and 0.3 M NaCl decelerated more slowly than that of WKY rats. The increased intake of hypertonic NaCl by SHR was due to a decrease in the decline in lick rate, suggesting that SHR are less responsive to ingestion-contingent negative feedback.  相似文献   
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BACKGROUND: Millions of people use the Internet as a source for health information yet little is understood about how the use of the Internet for health information is related to the doctor-patient relationship. OBJECTIVE: We conducted the present study to understand the association between one's interest in using the Internet for general and quality-oriented health information and attitudes about one's communications with health care provider(s). DESIGN: Cross-sectional survey. SETTING: Four community-based primary care practices in Rhode Island. MEASUREMENTS: A single self-administered survey included items to measure: interest in using the Internet to look for general and quality-oriented information and a patient's perceptions of the degree to which their doctors over the previous year have: (1) given them information and (2) engaged them in the decision-making process. RESULTS: A total of 300 patients completed the survey. Among patients without Internet access, interest in using the Internet for health related activities was less among patients who felt that their doctor gave less information: Odds ratio 0.83 (95% CI, 0.70-0.98) and greater among patients who felt that their doctor engaged them more in decision making: Odds ratio 1.3 (95% CI, 1.1-1.6). Among patients with Internet access, we found no relationship between interest in using the Internet for health related activities and measures of patient-physician communication or patient-physician decision making. CONCLUSIONS: Interest in using the Internet for health information is greater for those who (1) felt their doctors provided less information and (2) felt their doctors engaged them more in the decision-making process, but this is true only for those without access to the Internet.  相似文献   
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Spaced training is generally more effective than massed training for learning and memory, but the molecular mechanisms underlying this trial spacing effect remain poorly characterized. One potential molecular basis for the trial spacing effect is the differential modulation, by distinct temporal patterns of neuronal activity, of protein synthesis-dependent processes that contribute to the expression of specific forms of synaptic plasticity in the mammalian brain. Long-term potentiation (LTP) is a type of synaptic modification that may be important for certain forms of memory storage in the mammalian brain. To explore the role of protein synthesis in the trial spacing effect, we assessed the protein synthesis dependence of hippocampal LTP induced by 100-Hz tetraburst stimulation delivered to mouse hippocampal slices in either a temporally massed (20-s interburst interval) or spaced (5-min interburst interval) fashion. To extend our studies to the behavioral level, we trained mice in fear conditioning using either a massed or spaced training protocol and examined the sensitivity of long-term memory to protein synthesis inhibition. Larger LTP was induced by spaced stimulation in hippocampal slices. This improvement of synaptic potentiation following temporally spaced synaptic stimulation in slices was attenuated by bath application of an inhibitor of protein synthesis. Further, the maintenance of LTP induced by spaced synaptic stimulation was more sensitive to disruption by anisomycin than the maintenance of LTP elicited following massed stimulation. Temporally spaced behavioral training improved long-term memory for contextual but not for cued fear conditioning, and this enhancement of memory for contextual fear was also protein synthesis dependent. Our data reveal that altering the temporal spacing of synaptic stimulation and behavioral training improved hippocampal LTP and enhanced contextual long-term memory. From a broad perspective, these results suggest that the recruitment of protein synthesis-dependent processes important for long-term memory and for long-lasting forms of LTP can be modulated by the temporal profiles of behavioral training and synaptic stimulation.  相似文献   
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Physician-resource planning activities have increased dramatically in Canada since the release of the Barer-Stoddart report, "Toward Integrated Medical Resource Policies for Canada" in 1991. One of the key concepts of the Barer-Stoddart report is the "medical career life cycle," beginning with entry to medical school and ending with exit from practice. To apply this concept in a planning context, it is essential to have a current information base that will contain data on numbers of physicians, where they are, what they do, and how active they are. In addition, a longitudinal capability is important for understanding issues such as retention and attrition. The objective of this article is to review and assess recent initiatives in the establishment of physician-resource databases in Canada by medical associations, governments, licensing bodies, certifying colleges, and other groups with a respect to comprehensiveness and comparability of key data elements and their ability to address key policy questions in physician-resource planning and to identify opportunities for collaboration and links.  相似文献   
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Details the results of an attempt to identify the impact of a comprehensive management development programme on organizational effectiveness within the health service public sector. Concludes that management development programmes must have a prespecified set of strategically linked outcomes, identifying the benefits to the organization, and a set of critical success factor measures to determine their achievement or otherwise. Programmes which do not result in managers feeling empowered will be criticized in not impacting positively on the organization.  相似文献   
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Information was collected about 302 women referred for breast symptoms and seen in surgical outpatient or outreach clinics during one month at two hospitals in Sheffield. Three-quarters of the women (n = 244) were referred to specialist breast clinics, 22% (n = 70) were referred to general surgical clinics and 3% (n = 6) were referred to outreach clinics. The ages of the women ranged from 16 to 85 years with a mean and median age of 45 years. Some 200 women (66%) presented with a lump or lumpiness, 42 women (14%) presented with pain, 29 women (10%) had a skin and/or nipple problem, and the remaining 31 women (10%) were concerned about their family history or reported other symptoms. A total of 23 women (8%) were diagnosed as having cancer, 180 (60%) were diagnosed as having benign breast disease, and 99 (33%) were diagnosed as normal. Of the 23 women with cancer, 22 were over 40 years of age; 21 women presented with a lump, one presented with pain, and one presented with metastatic disease. The time required to reach a final clinical diagnosis varied from the same day as the clinic visit to 35 weeks, with a median time of 3 weeks. Surgeons assessed the appropriateness of GPs' referrals for 257 cases and judged that 122 (47%) could have been managed by a GP. The implications of the findings for the organisation of specialist outpatient clinics are discussed, and a categorisation of women as either urgent or routine cases is suggested.  相似文献   
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