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991.
The fascioliasis situation in humans and livestock of Iranian Mazandaran is analysed for the first time. Coprological studies showed 7.3% and 25.4% global prevalences in sheep and cattle, respectively. Studies in slaughterhouses indicate that sheep and cattle may be the main reservoir species, buffaloes may play local roles in the transmission, and goats and horses probably only participate sporadically. Morphometric studies by computer image analysis showed that forms intermediate between Fasciola hepatica and F. gigantica appear in addition to both species. A total of 107 infected humans were diagnosed during the 1999–2002 period, which suggests that fascioliasis may be widespread. The absence of differences in human fascioliasis among gender and age groups differs from other human endemic areas. Both human and animal infections show marked differences between western and eastern Mazandaran. Traditions in herbal condiments for human consumption, methods of animal husbandry and annual rainfall may explain the higher prevalences in western Mazandaran.  相似文献   
992.
BACKGROUND: Most studies on spinal cord infarction have been conducted in single centres; they usually consisted of case reports, or of larger series of patients recruited over a large period of time, with heterogeneous diagnostic procedures. Therefore, the clinical and radiological presentation of spinal cord infarcts and their short term outcome remain poorly understood. OBJECTIVE: To define clinical and magnetic resonance imaging (MRI) findings, and short term outcome in patients with spinal cord infarcts. METHODS: The authors prospectively included patients within 10 days of onset. An MRI scan was required and repeated when initially normal. RESULTS: Twenty eight consecutive patients were included over a 24 month period in 16 neurological centres. The infarct was cervical in seven patients, thoracic in three, thoracolumbar in 15, and restricted to the conus in three. On axial MRI scans the infarct was located in the central territory of the anterior spinal artery in 21 patients, and in the peripheral arterial territory in three. At month two, 15 patients had a good outcome and 13 had a poor outcome, including three deaths. Patients who, at onset, could not walk, had bladder dysfunction, or proprioceptive deficits were more likely to have a poor outcome. At month two, pain had occurred in 10 of the 25 survivors and was associated neither with the initial severity, nor the extent of the infarct on MRI. CONCLUSION: The two month outcome mainly depends on the initial severity of the neurological deficit; however, a few patients with a severe impairment at onset had a good outcome, especially when proprioception remained normal at onset. The study does not support the hypothesis that pain occurs more frequently in small spinal infarcts.  相似文献   
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994.
The role of routine polio immunization in the post-certification era   总被引:4,自引:0,他引:4  
The role of routine vaccination against poliomyelitis for the post-certification era remains an important area for policy decision-making. Two critical decisions need to be taken: first, to continue or discontinue vaccination with the live attenuated oral poliovirus vaccine (OPV); and second, if OPV is to be discontinued, whether vaccination with inactivated poliovirus vaccine (IPV) is needed. Four potential vaccination scenarios can be constructed: stop all polio vaccination; continue with current vaccination policies (OPV, IPV, or sequential schedule); discontinue OPV, but continue IPV universally; or discontinue OPV, but continue IPV in selected countries. All possible scenarios require continued investments in a surveillance and response strategy, including a stockpile of polio vaccine. Continuing vaccination would limit the savings that could be applied to the control of other health priorities. This report reviews the key issues associated with each scenario, highlights the advantages and disadvantages of each scenario, and outlines the major challenges for policy decision-making.  相似文献   
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Mas M  Sabater E  Olaso MJ  Horga JF  Faura CC 《Brain research》2000,866(1-2):109-115
The development of tolerance, the sensitivity to morphine and the effective morphine plasma concentrations have been studied in Sprague-Dawley (SD-U) and Wistar (W) rats. Daily administration of morphine (10 mg/kg/12 h for 9 days) in W rats produced a reduction in morphine antinociception from day 1 (12+/-0 s) to day 9 (6.7+/-1. 9 s). Morphine antinociception in the SD-U rats did not change over the period of treatment. Naloxone abolished the antinociception of morphine in both opiate naive and chronically treated SD-U rats. The pharmacokinetic parameters of morphine and morphine-3-glucuronide did not differ significantly between strains. Both naive and chronically treated SD-U rats required smaller doses of morphine than W rats to obtain a maximum antinociceptive effect. Plasma concentrations following administration of the same dose of morphine, did not differ between strains or days of treatment. The range of morphine concentrations required to obtain a maximum effect were lower in SD-U rats, both on day 1 and day 8 when compared to W rats. These results show differences between the two strains with regard to both morphine sensitivity and development of tolerance, whilst also suggesting that the differences do not have a kinetic basis.  相似文献   
999.
BACKGROUND: Valid instruments to measure practitioners' attitudes towards clinical practice guidelines need to be developed. However, few of the available instruments have been thoroughly validated. OBJECTIVE: To adapt into French and to test the reliability and validity of a scale for measurement of attitudes towards guidelines developed by Elovainio et al. METHODS: A 27-item scale (divided into six dimensions) measuring attitudes towards guidelines was translated into French by two English native translators, reviewed and finalized by expert committee and administered to 314 practitioners who agreed to participate. Main practitioners' characteristics were collected. Item and dimension reproducibility were assessed for 62 practitioners by calculation of intraclass correlation coefficients. Internal construct validity was assessed by principal components analyses. Convergent and discriminant validity were analysed. RESULTS: Item response rates ranged from 82 to 100%. In the test-retest procedure, intraclass correlation coefficients for separate items ranged from 0.1 to 0.7 and those for dimensions were 0.7 [95% confidence interval (CI): 0.5-0.8] for usefulness, 0.5 (0.3-0.6) for reliability, 0.4 (0.2-0.5) for individual competence, 0.5 (0.3-0.6) for organizational competence, 0.7 (0.5-0.8) for impracticality and 0.4 (0.3-0.6) for availability. The factorial structure after Varimax rotation showed that none of the different solutions obtained had a strictly comparable structure to that of the original scale. External construct validity was satisfactory. CONCLUSION: This scale does not have satisfactory psychometric properties and therefore cannot confidently be used in future research assessing whether attitudes towards guidelines are a determining factor in physicians' compliance with guidelines. More research is needed to develop valid scales in a more rigorous procedure, involving qualitative and quantitative steps.  相似文献   
1000.
BACKGROUND: The finding of an antibody that reacts against a high-incidence blood group antigen always constitutes a complex transfusion problem because of the difficulty in finding compatible units. When the transfusion of incompatible RBCs is imperative, it would be of great interest to have access to techniques facilitating the prediction of the transfusion outcome. STUDY DESIGN AND METHODS: The case of a patient with alloanti-Kp(b) who required RBC transfusions is reported. The functional activity of this antibody was assessed by both the chemiluminescence test (CLT) and the survival of 51Cr-labeled RBCS: RESULTS: The CLT showed an opsonic index of 0.8 with Kp(b)-positive RBCs (normal values up to 1.6) in pretransfusion studies. During an elective surgical procedure, the patient required the transfusion of one incompatible unit of RBCs, which did not produce hemolysis. Two weeks after this incompatible transfusion, the opsonic index had risen to 11. Results of the 51Cr in vivo study, also performed at that time, indicated 24.3 percent survival of Kp(b)-positive RBCs at 60 minutes and 2.0 percent at 24 hours. CONCLUSION: Results of the CLT correlated with the in vivo transfusion outcome and later with the 51Cr survival study.  相似文献   
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