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991.
The aim of this article is to provide information about possibilities for medical students and doctors to obtain knowledge about international health. Increasing globalisation requires knowledge about international health in such a way that Danish doctors are able to diagnose and treat patients, regardless of the patient's nationality and ethnic background. Denmark has a global responsibility towards low and middle income countries to increase the standard of health. Increased knowledge and research in these countries are important both at an undergraduate and postgraduate level.  相似文献   
992.
Background: Sleep bruxism is the non-functional grinding or clenching of teeth during sleep. It may lead to tooth damage and myofascial pain. Although stress is discussed as a main causal agent, there is a lack of studies concerning coping strategies in patients with sleep bruxism. Purpose: The aim of the present study was to investigate whether bruxers, compared to non-bruxing individuals, apply maladaptive coping strategies. Method: Seventy-five sleep bruxers and 38 non-bruxers were selected by dental examination and tested by a German coping questionnaire (SVF78). Results: A significant difference in positive coping strategies was observed between the two groups. Bruxers reported less positive coping strategies, mainly less “reaction control” and “positive self-instructions.” In general, males reported less negative coping strategies. Conclusion: The reported effects demonstrate a deficit of functional coping strategies in bruxers, whereas strategies that enhance stress do not seem to be associated with sleep bruxism. Findings do not admit the conclusion that there is a causal association of maladaptive coping and bruxism. However, they support the approach of a multidisciplinary therapy involving psychological treatment.  相似文献   
993.
Though uncommon, kidney malformations are described in several cases of Townes-Brocks syndrome. By contrast, kidney failure has been reported as the presenting feature of Townes-Brocks syndrome on only one occasion. While the SALL1 gene, mutations of which result in the Townes-Brocks phenotype, is expressed in the developing kidney, the absence of other corroborative reports of kidney failure presenting in affected individuals suggests that the solitary observation of kidney failure is as likely due to chance as to causal association. In now reporting a further instance of this association, we review the literature, demonstrating that several other instances of kidney failure are in fact known, despite an incomplete dataset. These findings suggest that kidney failure may be a constituent element of the natural history of Townes-Brocks syndrome and raise the possible benefits of longitudinal survey for progressive kidney impairment in patients with this syndrome.  相似文献   
994.
Surveillance of group A streptococcal (GAS) infections was undertaken as a major component of the European Commission-funded project on severe GAS disease in Europe (strep-EURO). One aim of strep-EURO was to improve the quality of GAS characterization by standardization of methods. An external quality assurance study (EQA) was therefore carried out to evaluate current global performance. Eleven strep-EURO and seven other streptococcal reference centers received a panel of 20 coded GAS isolates for typing. Conventional phenotypic typing (based on cell surface T and M protein antigens and opacity factor [OF] production) and molecular methods (emm gene typing) were used either as single or combined approaches to GAS typing. T typing was performed by 16 centers; 12 centers found one or more of the 20 strains nontypeable (typeability, 89%), and 11 centers reported at least one incorrect result (concordance, 93%). The 10 centers that tested for OF production achieved 96% concordance. Limited availability of antisera resulted in poor typeability values from the four centers that performed phenotypic M typing (41%), three of which also performed anti-OF typing (typeability, 63%); however, concordance was high for both M (100%) and anti-OF (94%) typing. In contrast, the 15 centers that performed emm gene sequencing achieved excellent typeability (97%) and concordance (98%), although comparison of the performance between centers yielded typeability rates from 65 to 100% and concordance values from 83 to 100%. With the rapid expansion and use of molecular genotypic methods to characterize GAS, continuation of EQA is essential in order to achieve international standardization and comparison of type distributions.  相似文献   
995.
The study of the evolution of human immunodeficiency virus type 1 (HIV-1) requires blood samples collected longitudinally and data on the approximate time point of infection. Although these requirements were fulfilled in several previous studies, the infectious sources were either unknown or heterogeneous genetically. In the present study, HIV-1 env C2V3C3 (nt 7029-7315) evolution was examined retrospectively in a cohort of hemophiliacs. Compared to other cohorts, the area of interest here was the infection of six hemophiliacs by the same virus strain, that is, the infecting viruses shared an identical genome. As expected, divergence from the founder sequence as well as interpatient divergence of the predominant virus strains increased significantly over time. Based on the V3 nucleotide sequences, CCR5 usage was predicted exclusively throughout the whole period of infection in all patients. Interestingly, common patterns of viral evolution were detected in the patients of the cohort. Four amino acid substitutions within the V3 loop emerged and persisted subsequently in five (positions 305 and 308 of the HXB2 gp120 reference sequence) and six patients (positions 325 and 328 in HXB2 gp120), respectively. These common changes within the V3 loop are likely to be enforced by HIV-1 specific immune response.  相似文献   
996.
PURPOSE: Evaluation of water sorption and solubility of contemporary resin-based filling materials. METHODS: Specimens of Herculite (HE), Point 4 (P4), TetricCeram (TC), Miris (MI), TetricCeram HB (HB), Solitaire 2 (SO), SureFil (SU), Definite (DE), Admira (AD), Dyract AP (DY), Compoglass F (CO), and TetricFlow (TF) were prepared according to ISO 4049. Water sorption and solubility were measured after water storage at 37 degrees C for 7 days. RESULTS: Water sorption was HE 14 microg mm(-3), P4 17 microg mm(-3), TC 12 microg mm(-3), MI 13 microg mm(-3), HB 9 microg mm(-3), SO 18 microg mm(-3), SU 9 microg mm(-3), DE 14 microg mm(-3), AD 27 microg mm(-3), DY 19 microg mm(-3), CO 23 microg mm(-3), and TF 19 microg mm(-3). Solubility was HE 3 microg mm(-3), P4 3 microg mm(-3), TC 1 microg mm(-3), MI 0 microg mm(-3), HB 0 microg mm(-3), SO 3 microg mm(-3), SU 0 microg mm(-3), DE 1 microg mm(-3), AD 2 microg mm(-3), DY 4 microg mm(-3), CO -2 microg mm(-3), and TF 1 microg mm(-3). CONCLUSION: All materials met the corresponding requirement in ISO 4049. Filler load negatively correlated with water sorption but not with solubility. There was an influence of the resin matrix, too. No significant differences were found between composites, ormocers, and compomers.  相似文献   
997.
Progressive muscle wasting is a central feature of cancer-related cachexia and has been recognized as a determinant of poor prognosis and quality of life. However, until now, no easily assessable clinical marker exists that allows to predict or to track muscle wasting. The present study evaluated the potential of myoglobin (MG) plasma levels to indicate wasting of large locomotor muscles and, moreover, to reflect the loss of MG-rich fiber types, which are most relevant for daily performance. In 17 cancer-cachectic patients (weight loss 22%) and 27 age- and gender-matched healthy controls, we determined plasma levels of MG and creatine kinase (CK), maximal quadriceps muscle cross-sectional area (CSA) by magnetic resonance imaging, muscle morphology and fiber composition in biopsies from the vastus lateralis muscle, body cell mass (BCM) by impedance technique as well as maximal oxygen uptake (VO(2)max). In cachectic patients, plasma MG, muscle CSA, BCM, and VO(2)max were 30-35% below control levels. MG showed a significant positive correlation to total muscle CSA (r = 0.65, p < 0.001) and to the CSA fraction formed by type 1 and 2a fibers (r = 0.80, p < 0.001). However, when adjusted for body height and age by multiple regression, MG yielded a largely improved prediction of total CSA (multiple r = 0.83, p < 0.001) and of fiber type 1 and 2a CSA (multiple r = 0.89, p < 0.001). The correlations between CK and these muscle parameters were weaker, and elevated CK values were observed in 20% of control subjects despite a prior abstinence from exercise for 5 days. In conclusion, plasma MG, when adjusted for anthropometric parameters unaffected by weight, may be considered as a novel marker of muscle mass (CSA) indicating best the mass of MG-rich type 1 and 2a fibers as well as VO(2)max as an important functional readout. CK plasma levels appear to be less reliable because prolonged increases are observed in even subclinical myopathies or after exercise. Notably, cancer-related muscle wasting was not associated with increases in plasma MG or CK in this study.  相似文献   
998.
Summary Objectives: HIV/AIDS surveillance methods are under revision as the diversity of HIV epidemics is becoming more apparent. The so called “2nd generation surveillance (SGS) systems” aim to enhance surveillance by broadening the range of indicators to prevalence, behaviors and correlates, for a better understanding and a more complete and timely awareness of evolving epidemics. Methods: Concepts of HIV SGS are reviewed with a special focus on injecting drug users, a major at-risk and hard to reach group in Europe, a region with mainly low or concentrated epidemics. Results: The scope of HIV/AIDS surveillance needs to be broadened following principles of SGS. Specifically for IDUs we propose including hepatitis C data as indicator for injecting risk in routine systems like those monitoring sexually transmitted infections and information on knowledge and attitudes as potential major determinants of risk behavior. Conclusions: The suggested approach should lead to more complete and timely information for public health interventions, however there is a clear need for comparative validation studies to assess the validity, reliability and cost-effectiveness of traditional and enhanced HIV/AIDS surveillance systems. Submitted: 24 October 2005; Revised: 19 June 2006; Accepted: 5 October 2006  相似文献   
999.
OBJECTIVE: The aim of the present study was to examine the immune-modulating effect of two different fat blends enriched with a low dose of anti- or proinflammatory polyunsaturated fatty acids on the fatty acid status and subsequently on the immune response of healthy volunteers. METHODS: Thirty healthy volunteers were randomly assigned to group A (anti-inflammatory blend rich in polyunsaturated fatty acids: alpha-linolenic acid, 240 mg/d; eicosapentaenoic acid, 120 mg/d; stearidonic acid, 49 mg/d; and gamma-linolenic acid, 73 mg/d) or group B (arachidonic acid, 40 mg/d; containing an inflammatory fat blend) for a 2-wk dietary supplementation period. Concentrations of interleukin-8, interleukin-10, tumor necrosis factor-alpha, prostaglandins E(1) and E(2), and leukotriene B(4) were investigated before, after 2 wk of supplementation, and 2 wk after stopping supplementation using a whole blood ex vivo lipopolysaccharide-stimulation assay. RESULTS: Plasma concentrations of alpha-linolenic acid and eicosapentaenoic acid were significantly increased in group A. In addition, dietary fat blends influenced eicosapentaenoic acid concentration in erythrocyte membranes. Supplementation of the fat blends resulted in contrasting effects on the expression of lipid mediators and cytokines after ex vivo lipopolysaccharide stimulation. Release of prostaglandin E(1) and leukotriene B(4) were significantly decreased in group A, whereas prostaglandin E(2) and interleukin-10 concentrations were significantly increased in group B. No effect on interleukin-8 or tumor necrosis factor-alpha release was found after supplementation with either fat blend. CONCLUSIONS: These results show an immune-modulating effect of a low-dose dietary polyunsaturated fatty acid supplementation. However, further studies regarding fat-blend composition and period of supplementation in patients with inflammatory conditions are required.  相似文献   
1000.
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