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This study aimed to describe the intake and food sources of macronutrients in vegetarian and non-vegetarian adolescent females. Cross-sectional data was collected between February and September 2019. Adolescent females, aged 15 to 18 years old, were recruited throughout New Zealand. Intakes were assessed via two 24-h diet recalls, adjusted to represent usual intake using the multiple source method. Of the 254 participants, 38 self-identified as vegetarian. Vegetarians had similar carbohydrate and fat intakes compared to non-vegetarians; however, their protein intakes were 2.1% kJ lower (95% confidence interval (CI) −3.0 to −1.1%). Vegetarians also consumed 1.1% kJ less saturated fat (95% CI –2.1 to −0.1%), 1.3% kJ (95% CI 0.7 to 1.9) more polyunsaturated fat, and 5 g/day (95% CI 1.8 to 8.0) more fiber than non-vegetarians. When consumed, bread-based dishes and discretionary foods were the highest sources of energy, fat, and carbohydrate in both vegetarians and non-vegetarians. This suggests that some adolescents, including vegetarians, were obtaining high amounts of fat and carbohydrate from food groups associated with poorer dietary quality. We recommend further research to assess how the changing food environment is influencing vegetarian eating patterns and their associations with health outcomes in the wider population.  相似文献   
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The effects of incubation of cultured rat skeletal myotubes in ouabain were studied on the number of [3H]ouabain binding sites and electrogenic component of membrane potential. Ouabain treatment for 2–6 days increased the number of binding sites, resting membrane potential (Em) and the ouabain-sensitive component of Em in the muscle cells. The findings strengthen the idea that Na, K-ATPase has an important role in regulation of Em in cultured skeletal muscle and suggest that Na-K pump inhibition during development may be a regulatory mechanism for cellular synthesis of Na, K-ATPase.  相似文献   
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BACKGROUND: Accurate measurement of neonatal neurological integrity is critical for early identification of pre-term and full-term infants at-risk for developmental disability. The Neurobehavioural Assessment for Pre-term Infants (NAPI) was developed to measure the progression of neurobehavioural development in pre-term infants born between 32 weeks post-conceptional age (PCA) and term. This instrument has many unique advantages; however, criterion validity is unknown and results are subsequently difficult to interpret. OBJECTIVES: This study examined the concurrent validity of the NAPI against a criterion instrument, the Einstein Neonatal Neurobehavioural Assessment Scale (ENNAS), which measures similar constructs and has demonstrated excellent reliability and validity. METHODS: A sample of 41 pre-term and full-term infants (40 +/- 2 weeks) was assessed with the NAPI and ENNAS on the same day. RESULTS: The findings demonstrated that correlations between similar NAPI clusters and ENNAS clusters ranged from 0.35-0.65 and correlations between many similar individual NAPI and ENNAS items ranged from 0.40-0.60. Two NAPI clusters also discriminated between normal, abnormal and suspect performance on the ENNAS. CONCLUSION: The NAPI has many unique advantages as a tool. It examines neonates serially, has established weekly normative data and requires minimal infant handling. This study provides new validation of the NAPI instrument.  相似文献   
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PURPOSE: To assess the effect of commonly used computed tomographic (CT) section thicknesses on metastatic tumor measurements calculated with unidimensional, bidimensional, area, and volumetric methods. MATERIALS AND METHODS: Analysis and data collection were approved by the Institutional Review Board, with waived informed patient consent. Forty-two pulmonary metastases in 10 patients (three men and seven women; age range, 43-83 years; mean age, 65.4 years) were analyzed on CT scans obtained with 3.75-, 5.0-, and 7.5-mm section thicknesses. The lesions were automatically delineated by using a three-dimensional multicriteria segmentation algorithm. Unidimensional (the largest diameter), bidimensional (the product of the two maximal perpendicular diameters), maximal cross-sectional area, and volumetric measurements were automatically obtained for each pulmonary lesion on each section thickness. Means and variances were calculated, and the differences across the three section thicknesses for each of the four measurements were studied by using linear mixed-effects models. The Levene test was used to study the equality of variances. RESULTS: Differences in the means for unidimensional, bidimensional, and area measurements were significant between a section thickness of 3.75 and 5.0 mm (unidimensional, P=.05; bidimensional, P=.05; area, P=.01) and 3.75 and 7.5 mm (unidimensional, P=.06; bidimensional, P=.03; area, P=.02), but not 5.0 and 7.5 mm. There was a significant difference in volumetric measurement as section thickness decreased from 7.5 to 5.0 mm (P <.001) and from 7.5 to 3.75 mm (P <.001). Although there was a slight trend for differences in the variances across section thickness for each measurement, none of the differences were significant. CONCLUSION: Volumetric tumor measurements change with a reduction in section thickness from 7.5 to 5.0 and 3.75 mm. For unidimensional measurement, no change was found when thickness decreased from 7.5 to 5.0 mm.  相似文献   
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RasGRP is a family of guanine nucleotide exchange factors that activate small GTPases and contain a C1 domain similar to the one present in protein kinase C (PKC). In this study, we examined the interaction of RasGRP3 and PKC in response to the phorbol ester PMA. In Chinese hamster ovary or LN-229 cells heterologously expressing RasGRP3, phorbol 12-myristate 13-acetate (PMA) induced translocation of RasGRP3 to the perinuclear region and a decrease in the electrophoretic mobility of RasGRP3. The mobility shift was associated with phosphorylation of RasGRP3 on serine residues and seemed to be PKCdelta-dependent because it was blocked by the PKCdelta inhibitor rottlerin as well as by a PKCdelta kinase-dead mutant. Using coimmunoprecipitation, we found that PMA induced the physical association of RasGRP3 with PKCdelta and, using in situ methods, we showed colocalization of PKCdelta and RasGRP3 in the perinuclear region. PKCdelta phosphorylated RasGRP3 in vitro. Previous studies suggest that ectopic expression of RasGRP3 increases activation of Erk1/2. We found that overexpression of either PKCdelta or RasGRP3 increased the activation of Erk1/2 by PMA. In contrast, coexpression of PKCdelta and RasGRP3 yielded a level of phosphorylation of Erk1/2 similar to that of control vector cells. Our results suggest that PKCdelta may act as an upstream kinase associating with and phosphorylating RasGRP3 in response to PMA. The interaction between RasGRP3 and PKCdelta points to the existence of complex cross-talk between various members of the phorbol ester receptors which can have important impact on major signal transduction pathways and cellular processes induced by phorbol esters or DAG  相似文献   
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Comparing the accuracy of two screening tests is ideally achieved by administering both tests as well as a gold standard test to all study subjects. In practice, a more ethical screen positive study design is often used, one that requires gold standard determination only for subjects that screen positive on either test under investigation. Although it is not possible to quantify the absolute accuracy of each test with such a design,the relative accuracy of the tests can be estimated. Since relative accuracy estimation has poor small sample properties, adjusted estimators based on adding constants to the observed data have been proposed. The adjusted estimators have the advantage that they yield point and variance estimates of relative accuracy in all settings. However, we show through both theory and numerical examples that adding constants to the data can be beneficial or detrimental to small sample performance. Furthermore, the performance of the adjusted estimator depends not only on the magnitude of the constant but also on parameters that cannot be estimated with data from a screen positive study, making selection of an optimal constant difficult in practice. We also examine the performance of the adjusted estimator using data from a study comparing the accuracy of two screening tests for cervical cancer.  相似文献   
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