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51.
In the early 1970s, affirmative-action programs were introduced to accomplish a number of social goals, including increasing the supply of minority physicians and improving the health care of the poor. To assess the success of such programs, we analyzed data on people who graduated from U.S. medical schools in 1975 to determine how specialty choice, practice locations, patient populations served, and board-certification rates differ between minority and nonminority graduates. A larger proportion of minority graduates (55 per cent vs. 41 per cent, P less than 0.001) chose the primary-care specialties of family practice, general internal medicine, general pediatrics, and obstetrics-gynecology. Significantly more minority physicians (12 per cent vs. 6 per cent, P less than 0.01) practiced in locations designated as health-manpower shortage areas by the federal government and had more Medicaid recipients in their patient populations (31 per cent for blacks, 24 per cent for Hispanics, 14 per cent for whites; P less than 0.001). Physicians from each racial or ethnic group served disproportionately more patients of their own racial or ethnic group (P less than 0.001), but minority physicians did not serve significantly more persons from other racial or ethnic minority groups than did nonminority physicians. Many minority physicians served patient populations much like those of their nonminority colleagues, which indicates that substantial integration of the medical marketplace has taken place. Significantly fewer minority graduates had become board-certified by 1984 (48 per cent vs. 80 per cent, P less than 0.001), and most of this disparity was associated with differences in premedical-school characteristics and in the patient populations they served. Our analysis shows that minority graduates of the medical school class of 1975 are fulfilling many of the objectives of affirmative-action programs.  相似文献   
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The degree of muscular ischemia and its reversibility can be quantified in the early stages. This histochemical enzymatic study utilized Nitroblue tetrazolium (NBT) which when reduced by tissue dehydrogenase produces a blue pigment: "formazan." Seventy Wistar rats were subjected to transient hindlimb ischemia by means of a tourniquet for 3, 6, 9, 12, 15 and 18 hours, followed by reperfusion. Microsurgical muscle biopsies were obtained in each rat at 1 and 12 hours, and 3, 7, 14 days after reperfusion. Time increased in muscle staining demonstrated a succino-dehydrogenase deficit confirmed by clinical and histopathological follow-up. NBT staining time was 2 minutes (+/- 8 sec.) in the control group, between 2 and 6 minutes in the reversible ischemia group (rats with 3 and 6 hours of tourniquet), and more than 9 minutes (+/- 14 sec.) in the irreversible ischemia group (animals with more than 9 hours of tourniquet). In vascular surgery and in limb reimplantation this protocol is a practical method of evaluating cytoplasmic enzymatic activity and the status of myofibrillar oxidation in the early phases of ischemic injury, before histologic changes are clearly delineated.  相似文献   
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Maternal and infant nutrition are problematic in areas of Ethiopia. Health extension workers (HEWs) work in Ethiopia’s primary health care system, increasing potential health service coverage, particularly for women and children, providing an opportunity for health improvement. Their roles include improving maternal and infant nutrition, disease prevention, and health education. Supporting HEWs’ practice with ‘non-clinical’ skills in behavior change and health communication can improve effectiveness. This intervention study adapted and delivered a UK-developed training intervention for Health Extension Workers (HEWs) working with the United Nations World Food Programme in Ethiopia. The intervention included communication and behavioral training adapted with local contextual information. Mixed methods evaluation focused on participants’ reaction to training, knowledge, behavior change, and skills use. Overall, 98 HEWs were trained. The intervention was positively received by HEWs. Pre-post evaluations of communication and behavior change skills found a positive impact on HEW skills, knowledge, and motivation to use skills (all p < 0.001) to change women’s nutritional behavior, also demonstrated in role-play scenarios. The study offered substantial learning about intervention delivery. Appropriate cultural adaptation and careful consideration of assessment of psychological constructs are crucial for future delivery.  相似文献   
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PURPOSE: Most medical schools test their students throughout the curriculum using in-house examinations written by the faculty who teach the courses. The authors assessed the quality of in-house examinations used in three U.S. medical schools. METHOD: In 1998, nine basic science examinations from the three schools were gathered and each question was subjected to quality assessment by three expert biomedical test developers, each of whom has had extensive experience in reviewing and evaluating questions for the United States Medical Licensing Examination (USMLE) Steps 1 and 2. Questions were rated on a five-point scale: 1 = tested recall only and was technically flawed to 5 = used a clinical or laboratory vignette, required reasoning to answer, and was free of technical flaws. Each rater made independent assessments, and the mean score for each question was calculated. Mean quality scores for National Board of Medical Examiners (NBME) who were trained question writers were compared with the mean scores for question writers without NBME training. The raters' quality assessments were made without knowledge of the test writers' training background or the study's hypothesis. RESULTS: A total of 555 questions were analyzed. The mean score for all questions was 2.39 +/- 1.21. The 92 questions written by NBME-trained question writers had a mean score of 4.24 +/- 0.85, and the 463 questions written by faculty without formal NBME training had a mean score of 2.03 +/- 0.90 (p <.01). CONCLUSIONS: The in-house examinations were of relatively low quality. The quality of examination questions can be significantly improved by providing question writers with formal training.  相似文献   
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In this essay, we discuss assessment of students' understanding of the basic biomedical sciences during the basic science component of medical education. Because we strongly believe that assessment should follow from and be congruent with course and curricular goals, the first section discusses recent trends in basic science education: where it's been and where it appears to be headed. The second section discusses considerations in the design of an assessment system that reflects curricular goals and encourages students to achieve them; it also identifies some research issues that we think merit attention. In the last section, we outline some of the special assessment issues and problems that arise in the context of problem-based learning (PBL) and discuss the merits of some of these novel assessment approaches, as well as the use of more traditional methods in PBL curricula.This revised version was published online in September 2005 with corrections to the Cover Date.  相似文献   
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St. Paul-Ramsey Medical Center in St. Paul, MN became one of the first hospitals in the United States to initiate a "stockless" par level inventory system. Successes with stockless led the hospital to look at implementing it in the OR to achieve a reduction of expense to revenue. Materiel Management and Surgical Services discussed a number of issues relevant to implementing a stockless program, including product flow, accuracy and cost of case carts and preference cards, item pricing, committed usage of items brought into the system and establishment of a steering committee. Specific OR issues and practices required evaluation and adjustment, such as the routine use of emergency direct ordering. Information systems support was brought in and a products committee established to do education and oversee the program. Savings for 1993-94 were $185,146.  相似文献   
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