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71.
ObjectiveBuilding on the original taxonomy of hospital‐based health systems from 20 years ago, we develop a new taxonomy to inform emerging public policy and practice developments.Data SourcesThe 2016 American Hospital Association''s (AHA) Annual Survey; the 2016 IQVIA Healthcare Organizations and Systems (HCOS) database; and the 2017‐2018 National Survey of Healthcare Organizations and Systems (NSHOS).Study DesignCluster analysis of the 2016 AHA Annual Survey data to derive measures of differentiation, centralization, and integration to create categories or types of hospital‐based health systems.Data CollectionPrincipal components factor analysis with varimax rotation generating the factors used in the cluster algorithms.Principal FindingsAmong the four cluster types, 54% (N = 202) of systems are decentralized (−0.35) and relatively less differentiated (−0.37); 23% of systems (N = 85) are highly differentiated (1.28) but relatively decentralized (−0.29); 15% (N = 57) are highly centralized (2.04) and highly differentiated (0.65); and approximately 9 percent (N = 33) are least differentiated (−1.35) and most decentralized (−0.64). Despite differences in calculation, the Highly Centralized, Highly Differentiated System Cluster and the Undifferentiated, Decentralized System Cluster were similar to those identified 20 years ago. The other two system clusters contained similarities as well as differences from those 20 years ago. Overall, 82 percent of the systems remain relatively decentralized suggesting they operate largely as holding companies allowing autonomy to individual hospitals operating within the system.ConclusionsThe new taxonomy of hospital‐based health systems bears similarities as well as differences from 20 years ago. Important applications of the taxonomy for addressing current challenges facing the healthcare system, such as the transition to value‐based payment models, continued consolidation, and the growing importance of the social determinants of health, are highlighted.  相似文献   
72.
73.
We studied 22 gynecological tumors for mutations in exons 5 through 8 of the p53 gene by means of SSCP analysis, using a simplified, nonradioactive technique developed at our laboratory. In order to test the procedure, we carried it out in parallel with the usual radioactive one. Two coincident mutations (in exons 5 and 8) were found by means of both methods. However, an additional one in exon 6 was found by means of our nonradioactive technique. This simplified method for SSCP-analysis of the p53 gene in human tumors is faster, easier and cheaper to perform than the conventional radioactive method, and yields equivalent results. It could be thus an excellent candidate for routine use in the clinical setting.  相似文献   
74.
We describe a girl with a facial haemangioma, associated with other vascular anomalies: agenesis of the internal carotid artery, cerebral cortical dysplasia and hypoplasia of the cerebral hemisphere on the same side of the angioma. We studied the patient by conventional arteriography, T1- and T2-weighted MRI and magnetic resonance angiography.  相似文献   
75.
Iron deficiency is the most frequent form of nutritional anemia, and infants represent one of the major risk groups. The present study was meant to evaluate the iron content of infant diets cooked in iron utensils and in aluminum utensils prepared by volunteer mothers at home. The iron content was analyzed by atomic absorption spectrophotometry. The increase of iron in diets cooked in iron utensils was 12 to 44 times greater than in diets cooked in aluminum utensils. The pH and moisture of the diets cooked in the two types of utensils did not differ in a statistically significant manner. On the basis of these results, it was estimated that the increase in daily iron supply obtained by cooking the diet in iron utensils would be sufficient to satisfy the iron requirements of infants.  相似文献   
76.
Severe unilateral varus deformity of the distal end of the femur secondary to a focal fibrous lesion is reported. It is a malformative process rare at this level, this being the first report of it in the radiological literature. The conventional radiograph is pathognomonic and CT is useful in the confirmation of the fibrous tissue. Osteotomy is indicated only if the deformity progresses or the angle of varus is severe.  相似文献   
77.
Escherichia coli is the most common causative agent of urinary tract infection (UTI), and diagnosing this infection usually relies on bacteriologic methods. Nevertheless, screening methods can be useful for a rapid presumptive diagnosis even though some of these screening methods have low sensitivity or are expensive. To investigate a possible new alternative approach, an antigen-based immunoassay--enzyme-linked immunoelectrodiffusion assay (ELIEDA)--was standardized for screening for this bacterial infection. Combining counter-immunoelectrophoresis with an immunoenzymatic assay, the ELIEDA requires concentrated urine specimens, a cellulose acetate membrane, polyclonal antibodies to E. coli raised in rabbits, and peroxidase-labeled sheep antibodies to rabbit immunoglobulin G (IgG). This ELIEDA technique was evaluated using 244 urine specimens, 76 of them with E. coli, 47 with heterologous bacteria, and 121 without bacteria. In comparison to bacteriologic methods, the sensitivity, specificity, and positive and negative predictive values for the ELIEDA were 93.4%, 98.2%, 95.9%, and 97.1%, respectively. The data obtained suggest that this assay is useful for routine diagnostic screening for UTI caused by E. coli. In addition, since the ELIEDA stained membranes can be stored, this assay makes retrospective studies possible.  相似文献   
78.
The present study aimed to investigate the prevalence and seasonal variation of hypovitaminosis D (defined as serum 25-hydroxyvitamin D level below 30 nmol/l) among healthy subjects and hospitalized patients living in central Italy. We studied 297 subjects, 131 in February 1997 and 166 in July 1997, subdivided into four groups: (a) young healthy blood donors; (b) healthy postmenopausal women; (c) inpatients with various medical diseases and (d) inpatients engaged in long-term rehabilitation programmes because of various neurological disorders. In all subjects and patients serum levels of 25-hydroxyvitamin D were measured by radioimmunoassay. We found a significant seasonal variation (P < 0.0001) of serum 25-hydroxyvitamin D levels, mean values being higher in summer in all groups, except in patients with a longer hospitalization time (group (d)). In each group, a significantly higher prevalence of hypovitaminosis D was found in winter compared with summer time (P < 0.001), being unexpectedly high in postmenopausal women (winter 32% and summer 4.5%); furthermore, in both seasons, inpatients were characterized by the highest incidences of hypovitaminosis, particularly those in group (d) (winter 82.3% and summer 57.8%). The results of the present study emphasize the importance of 25-hydroxyvitamin D measurement, and the need to increase vitamin D intake in Italy; foodstuff fortification and supplement use must be considered in order to prevent negative effects of vitamin D deficiency on skeletal integrity.  相似文献   
79.
Involvement of Fas-Fas ligand interactions in graft rejection   总被引:4,自引:0,他引:4  
The Fas/Fas ligand (FasL) pathway has been shown to be important in T lymphocyte-mediated cell death and is a key peripheral immunoregulatory mechanism that limits expansion of antigen-activated lymphocytes. The expression of Fas by commonly transplanted organs such as the heart, lung, kidney, and liver suggests that these tissues may be targets of FasL-expressing allospecific cytotoxic T lymphocytes. In this review the current literature examining the Fas/FasL system as a potential cellular effector pathway in tissue injury is discussed. In addition to a deleterious role in destruction of graft tissue, Fas/FasL interactions may have a beneficial role in transplantation. Recent studies suggest that modulation of FasL in target tissue leads to deletion, via apoptosis, of graft infiltrating lymphoid cells. However, an equally compelling series of reports indicate that overexpression of FasL can lead to a heightened immune response. These data are reviewed in the context of strategies to achieve long term allograft survival.  相似文献   
80.
The rate of HIV replication is estimated to be about 10 billion particles a day, and the cell's structure is its primary defense against infection. Cell membranes provide a defense against infection by forming a tight bond, preventing cells from being invaded by other organisms. The complex process of how HIV enters a cell is explained, and various parts of the process are illustrated. One key step in the process is fusion, which is when a virus particle attaches to a T cell, and the virus and cell merge together, allowing the virus to enter the cell. Researchers hope to find ways to interfere with fusion, so as to prevent HIV infection. Trimeris, Inc. has developed a new drug called T-20, or pentafuside, that is capable of preventing HIV from infecting a target cell. Results from studies of T-20 are provided, and ongoing studies are described.  相似文献   
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