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71.
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Results are reported of studies of the hemoglobin from one member of a Canadian family with a mild erythrocytosis. This variant, which accounted for about 40% of the hemoglobin, could be separated from Hb A and Hb A2 by cation-exchange chromatography. Micro methodology allowed the characterization of a Leu----Val replacement at position beta 96(FG3). Hb Regina has an increased oxygen affinity, which adequately explains the hematological observations.  相似文献   
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Substitution of CM-cellulose for CM-Sephadex had yielded a superior microchromatographic method for distinguishing the AS, AC, SS, SC, and CC conditions at birth. On the translucent columns of CM-Sephadex, the hemoglobin zones are somewhat diffuse. However, the compact, well-defined zones on the CM-cellulose column facilitate the interpretation of the results even though the amount of sample is only 20 per cent as great. The CM-cellulose method is as simple and rapid as the original CM-Sephadex procedure.  相似文献   
75.
We report on a 16-month-old boy who presented with truncal ataxia and intermittent nystagmus. Magnetic resonance imaging (MRI) at 19 months showed a T (2)-hyperintensity of the splenium and the genu of the corpus callosum with extension into the adjacent frontal white matter. Diffusion tensor imaging (DTI) revealed a corresponding area of restricted diffusion, suggesting cytotoxic oedema. The extent and localisation of the signal abnormalities mimic tissue injury as seen in Marchiafava-Bignami disease (MBD). Metabolic investigations were normal. Follow-up imaging at 24 months showed a similar T (2)-hyperintensity of the corpus callosum and white matter while on DTI the cytotoxic oedema had resolved. Clinically a remaining truncal and gait ataxia, clumsiness and a developmental delay is seen. Goal of this case report is (a) to present a rare case of Marchiafava-Bignami-like injury of the corpus callosum in an infant and (b) to discuss the neuroradiological imaging findings including MRI and DTI.  相似文献   
76.
BACKGROUND AND PURPOSE: We hypothesized that, in acute cerebral ischemic stroke, anisotropic diffusion increases if T2 signal intensity is not substantially elevated and decreases once T2 hyperintensity becomes apparent. Our purpose was to correlate fractional anisotropy (FA) measurements with the clinical time of stroke onset, apparent diffusion coefficients (ADC), and T2 signal intensity. METHODS: Tensor diffusion-weighted images (DWIs) of 25 patients were obtained within 12 hours of symptom onset. Trace DWIs, ADCs, FAs, and echo-planar T2-weighted images (T2WI) were generated. Stroke and contralateral normal volumes of interest (VOIs) were outlined on DWIs and projected onto the inherently coregistered ADC map, FA map, and echo-planar T2WI. Mean signal intensity of the ischemic and contralateral normal VOIs were compared for relatives change in ADC, FA, and signal intensity on T2WIs. RESULTS: A significant negative correlation was observed between FA and T2 signal-intensity change (r = -0.61, P =.00009). A trend of correlation between FA signal intensity and time of onset were found (r = -0.438, P =.025). No significant correlation was found between ADC and FA values (r = -0.302, P =.134). The mean ADC reduction in the ipsilateral ischemic volume was 31% +/- 11 compared with the contralateral normal side. CONCLUSION: Change in FA is inversely correlated with T2 signal intensity and, to a lesser extent, the time of onset, but it is not well correlated with ADC values in the acute stage.  相似文献   
77.
Numerous observational studies showed associations of antioxidants (vitamins C and E) and folate intake with a reduced risk of cardiovascular disease, but randomized controlled clinical trials have generally not supported this hypothesis. The objective of this study was to investigate the effects of a daily dosage of 1000 mg vitamin C, 800 mg vitamin E, and 10 mg folate on markers of vascular function in 31 young healthy male adults. Cardiovascular values after a 12-week vitamin (14 subjects) or placebo (17 subjects) intervention were compared to baseline values. Cardiovascular parameters (blood pressure, stroke volume, heart rate, cardiac output, vascular resistance, arterial compliance) were measured continuously after an overnight fast under controlled circumstances with a Finometer device. Our main finding was a significant decrease (p = 0.03) in systolic blood pressure in the experimental group. No statistically significant changes were observed within other cardiovascular variables of the experimental group, but possible beneficial decreases in diastolic blood pressure and increases in arterial compliance after 12 weeks of vitamin supplementation were indicated. In conclusion, beneficial effects of antioxidants and folate were observed probably because the supplementation was used by young healthy subjects under carefully controlled conditions.  相似文献   
78.
Equalisation of socioeconomic differences in injury risks at school ages is investigated, considering changes in risk inequalities over time for various categories of road users. Three national cohorts of children were followed up after their entry in different compulsory school levels (about 190,000 subjects by cohort). Subjects were attributed a household socioeconomic status in 1990 and their traffic injuries were sought over a five-year period (1990--94) in the national hospital discharge and causes of death registers. Socioeconomic inequality was measured by year and cohort for various RTI (Road Traffic Injury) diagnoses using the Relative Index of Inequality (RII). Whether equalisation arose or not was assessed considering changes in RII scores within the five-year period, measured by Chi-squared test. RII scores were generally high except for bicycle-related injuries among boys from the oldest cohort throughout the follow up. This relative equality in bicycle-injury risk benefited boys from all socioeconomic groups. Also, there was some, though short lasting, equalisation in bicycle-related injury risk for the younger cohort at the end of the first grade of compulsory school. Hence, some but limited support to the concept of equalisation was found, especially among young male bicycle riders. Population-based intervention aimed at improving safety behaviours among bicycle or motor-vehicle users should target not only suspected class-related influences, but even influences from the school, peer group and youth culture. Transitional periods in modes of transportation are a major concern.  相似文献   
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Aim: To study the influence of dietary-supplied long-chain polyunsaturated fatty acids on structural brain maturation in preterm infants and to investigate parameters of functional brain development, relating them to structural maturation. Other studies have suggested that dietary supplementation of long-chain polyunsaturated fatty acids in preterm infants may enhance their visual development. The influence on structural brain development has never been evaluated. Methods: In a prospective, double-blind study, 42 formula-fed premature infants were randomized to be fed either a standard preterm formula without long-chain polyunsaturated fatty acids or an identical formula supplemented with docosahexaenoic acid (0.015 g/100 ml) and arachidonic acid (0.031 g/100 ml). Infants with significant cerebral damage, retinopathy, chronic disease or feeding problems were excluded. Follow-up was focused on assessment of cerebral myelination by MRI. Psychomotor, mental and visual development was analysed and flash-visual evoked potentials were recorded. Results: It was found that progress of myelination, mental and motor development and latencies of visual evoked potentials were not positively influenced by supplementation of long-chain polyunsaturated fatty acids. At each test age, visual acuity was slightly better in the supplemented infants than in the non-supplemented infants, but the difference never reached significance level Conclusion: Supplementation of long-chain polyunsaturated fatty acids did not have a demonstrable positive influence on structural brain maturation. Related to this finding, in this small cohort of preterm infants without significant neurological damage, sample size being restricted by strict inclusion criteria and MRI procedures, no significant positive effects were found on psychomotor, mental and visual development.  相似文献   
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