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941.
942.
John Sheehan MSc MEd DipFE RGN RMN RNT FRSH 《Journal of advanced nursing》1990,15(7):819-824
This paper focuses on 'why', 'what' and 'how' issues as they relate to the investigation of change in a nursing context. The why issues revolve around the need for change, and evolutionary and revolutionary change are discussed. Next the what issues are discussed and some variables involved in the change process are identified, and the role of change agents is outlined. Change strategies such as the power-coercive, the rational-empirical and the normative-re-education are discussed. Finally, the potential of action research in the context of bringing about change is advanced. 相似文献
943.
944.
K. M. Sheehan R. A. Cahill G. McGreal C. Steele M. F. Byrne W. O. Kirwan E. W. Kay D. J. Fitzgerald H. P. Redmond F. E. Murray 《Digestive and liver disease》2004,36(6):392-397
BACKGROUND: Both the expressions of the inducible form of cyclooxygenase-2 and the presence of bone marrow micrometastases are poor prognostic markers in patients with colorectal carcinoma. AIMS: As cyclooxygenase-2 expression in these tumours is associated with increased metastatic potential in vitro, our objectives were to determine the relationship between cyclooxygenase-2 and haematogenous spread to bone marrow. PATIENTS AND METHODS: Thirty-two patients with resection of colorectal carcinoma were evaluated (median age: 69.5 years). Bone marrow was obtained from all patients from both iliac crests before manipulation of the primary tumour. The tumours were of varying stages at diagnosis (5 Dukes' A, 14 Dukes' B, 11 Dukes' C and 2 Dukes' D). Tumour sections were stained for cyclooxygenase-2 using the avidin-biotin immunohistochemical technique. Extent of staining was graded depending on the percentage of epithelial cells staining positive for cyclooxygenase-2. Micrometastases were detected by staining contaminant cytokeratin-18 positive cells in the bone marrow aspirates by either immunohistochemical (ARAAP) or immunological (flow cytometry) methods. Fisher's exact probability test was used to calculate statistical significance. RESULTS: Cyclooxygenase-2 expression in the primary tumour was detected in 72% of the patients. Twelve (38%) patients had bone marrow micrometastases detected by either immunohistochemistry or flow cytometry. Of the 12 patients who had bone marrow micrometastases, 8 tumours demonstrated increased expression of cyclooxygenase-2 protein (66.6%). In contrast, 9 out of the 20 (45%) patients in whom micrometastases were not detected expressed increased levels of cyclooxygenase-2 (P = 0.29). When dividing the patients into subgroups of localised (Dukes' A and B) versus disseminated (Dukes' C and D) disease, there was no further association between cyclooxygenase-2 expression and bone marrow micrometastases (P = 0.179 and 1.0). CONCLUSION: In this pilot study, there was no association between cyclooxygenase-2 expression and bone marrow micrometastases in patients with otherwise localised or disseminated disease. 相似文献
945.
Precocious puberty after traumatic brain injury 总被引:2,自引:0,他引:2
After traumatic brain injuries in 33 prepubertal children, precocious puberty was observed in seven. Precocious puberty developed significantly more frequently in girls than in boys (54.5 versus 4.5%, P less than 0.01). Six children with precocious puberty were in coma for greater than or equal to 2 weeks. Follow-up computed tomography revealed cerebral atrophy or focal encephalomalacia in all children with and 69% of children without precocious puberty. There were no striking differences in incidence of motor or cognitive deficits or posttraumatic epilepsy in children with and without precocious puberty. In four of five children, basal sex steroid levels were elevated, and the response to luteinizing hormone releasing hormone stimulation revealed a pubertal pattern after the appearance of secondary sex characteristics. 相似文献
946.
Michal Hubka John A McDonald Selwyn Wong Edward L Bolson Florence H Sheehan 《Journal of the American Society of Echocardiography》2004,17(5):404-410
BACKGROUND: Characterizing left ventricular (LV) remodeling after myocardial infarction or LV shape change resulting from LV shape-restoration operation can yield valuable prognostic information. However, current methods measure only global parameters of LV shape. METHODS: We developed and validated a method for measuring change in regional LV shape by aligning a patient's follow-up 3-dimensional LV surface reconstruction to baseline surface. We tested the diagnostic power of 6 distance functions to detect a known shape deformation. To create the test data, the LV endocardial surface of a control subject was reconstructed using 3-dimensional echocardiographic techniques. The surface was deformed 9 different ways to model LV dilation (3 different locations and severities). Normal shape variability was defined from 18 serial studies of 6 control subjects. The severity of regional dilation was computed as the orthogonal distance between the aligned baseline and deformed LV surfaces. Deformation was quantified according to regional location using the 16-segment map of the LV. RESULTS: Normal LV shape variability was 3.38 mm. The LV deformations ranged from 2.95 to 8.02 mm. Gaussian distance function produced the highest accuracy for measuring deformation distances (P <.005 by analysis of variance). In addition, the gaussian function correctly identified the location of the maximum deformation in 6 of the 9 distorted surfaces. In the 3 remaining surfaces, the gaussian alignment selected an adjacent basal segment with a similar deformation distance (mean error: 0.2 +/- 0.17 mm). The gaussian function's accuracy in pinpointing the deformation equaled or exceeded the performance of the other 5 functions tested. CONCLUSION: This new method of aligning 3-dimensional LV surfaces in space facilitates detecting, measuring, and localizing regional shape change in the human LV independent of anatomic landmarks or geometric references. Potential applications include quantitative monitoring of change in regional LV shape after a pathologic process and/or surgical procedure to document efficacy of treatment and to assess prognosis. 相似文献
947.
Fitness testing and career progression in AFL football 总被引:1,自引:0,他引:1
Relationships between fitness testing and career progression in the Australian Football League (AFL) are under-explored. This study investigated relationships between anthropometric and fitness tests conducted at the annual AFL National Draft Camp and subsequent career progression of players. A total of 283 players was tested over three consecutive camps (1999-2001). The anthropometric and fitness measures were: height, mass, sum of skinfolds, 20-m sprint test, vertical jump (standing and bilateral running), agility run and a multi-stage incremental shuttle run. The five outcome variables were: drafted (yes/no), AFL debut (yes/no), number of AFL games played to the end of 2003, and subjective ratings of career potential and career value (5-point scale). Of 205 players (72%) subsequently drafted, 166 (59%) eventually made their AFL debut. Players drafted to AFL clubs were faster over 5 m, 10 m and 20 m, ran further in the shuttle run and ran marginally faster in the agility test than players not drafted. Multi-regression analysis showed small to moderate correlations (r = 0.27-0.31) between the designated outcome variables and selected fitness tests: 20-m sprint time (faster), agility run test (faster), and running vertical jump (higher absolute height and smaller difference between left and ride sides). Regression analysis for the standing vertical jump relative to standing reach height showed a counterintuitive negative correlation with positive outcomes, possibly reflecting non-compliance with testing procedures by the less successful athletes. We conclude that the 20-m sprint, jump, agility and shuttle run tests have a small but important association with career progression of AFL footballers. 相似文献
948.
The influence of the hemoglobin (Hgb) phenotype on mean erythrocyte volume was re-examined in the light of recent evidence indicating a poor correlation between manual and more precise automated methods of measurement. The present studies identified a 17.6% frequency of microcytosis in a population of nonanemic Black males, a value higher than previously appreciated. In addition, it was shown that the frequency of microcytosis was also a function of the Hgb phenotype. Thus, 9.4% of Hgb AA, 18.6% of AS and 26.5% of AC subjects had microcytic erythrocytes. The data presented are consistent with the hypothesis that both the alpha-gene complement and the beta-chain phenotype contribute to the erythrocytic mean corpuscular volume and that the frequency of microcytosis in a patient population is a function of both of these variables. 相似文献
949.
950.