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PURPOSE: Chart notes are used to support billing codes under the evaluation and management guidelines of the Health Care Financing Administration (HCFA), in addition to serving as a record of the visit. To better understand the effect of the HCFA documentation guidelines, the authors collected data on how the guidelines affect participation by university- and community-based faculty in clinical education programs. METHOD: In 2000, the authors sent six copies of their questionnaire to the associate deans of the 125 U.S. medical schools and requested they distribute them to all core clerkship directors. The questionnaire consisted of multiple-choice and short-answer questions regarding documentation of medical visits, participation of community-based faculty, understanding of HCFA documentation guidelines, and effects on education programs. RESULTS: The response rate was about 50%. Most of the 379 clerkship directors who responded (77%) stated they were aware the HCFA documentation guidelines include specifications regarding the role medical students can play and documentation of medical visits, and 64% indicated they were concerned the guidelines would affect their educational programs. Concerns included the loss of student independence and active participation in the patient care environment (37), time constraints and the changing balance between education and service (16), loss of faculty and decreased morale (11), and decreased quality of care for patients (7). CONCLUSION: Leaders of medical education must work to modify these guidelines to protect the quality of patients' care, while maximizing students' educational opportunity and participation.  相似文献   
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Two thousand nine hundred and ninety-four reports of OSHA-reportable occupational injury or illness cases in 1984 from member companies of a national trade association of semiconductor manufacturing firms were analyzed. The 37 participating manufacturing facilities represented 16 companies employing over 95,000 persons, or approximately one-third of the U.S. work force for this industry in 1984. The annual incidence rate for all reportable injuries and illnesses was 2.7 per 100 full-time employees (FTE) for men and 3.7 per 100 FTE for women. Strains, sprains, or dislocations were the most frequently reported incidents (N = 956 [31.9%]), followed by cuts, lacerations, punctures, scratches, and abrasions (N = 445 [14.9%]), and chemical burns (N = 401 [13.4%]). Increased work-loss days per case were associated with manufacturing sites that did not have an employee health clinic on the premises, with custodial occupations, and with female gender.  相似文献   
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Mature (average patient age = 29.5 yr, closed apical foramen) and immature (average patient age = 17.5 yr, open apical foramen) root shards were placed in dialysis tubing and demineralized to completion using either 10% disodium EDTA plus protease inhibitors or 0.6 N HCl. The demineralized shards were re-extracted (five times) with 0.05 M tris-HCl, 1.0 M NaCl and then collagenase digested. No major differences were observed in chromatograms of extracts, re-extracts or collagenase digests from root shards demineralized in either way. In contrast, chromatograms of immature and mature roots showed qualitative differences. Chromatograms of mature roots demineralized in either way showed broader protein peaks and less organic phosphorus than those from immature tooth roots. A distinct band amid degraded phosphoprotein (150 K) was found in SDS-PAGE gels (7.5%) from EDTA-extracted immature tooth roots but not from mature tooth roots. Electroelution of this band revealed a typical phosphoprotein amino-acid profile containing increased aspartic acid and serine residues. Comparison of the total phosphoprotein and amino acid composition of extracts, re-extracts and collagenase digests revealed that phosphoprotein, serine and to a lesser extent aspartic acid were recovered in greater quantities from immature roots than mature tooth roots. These data suggest that the degree of maturation is crucial to the isolation of an intact phosphoprotein and provides additional evidence that human dentine phosphoprotein undergoes amino acid compositional changes during maturation.  相似文献   
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BACKGROUND--Office-based anticoagulation monitors offer significant advantages in convenience, yet their performance has been inadequately characterized. METHODS--We characterized the performance of a portable anticoagulation monitoring system with respect to precision and agreement with a reference laboratory. Eighty-five patients from a university outpatient anticoagulation clinic provided 143 whole blood sample pairs for evaluating agreement between the monitor and the laboratory. Fifty-four patients each provided a second pair of samples for assessing the monitor's precision, and 23 pairs of measurements from the reference laboratory were used for assessing the laboratory's precision. Anticoagulation was measured using International Normalized Ratio (INR) values. Agreement between monitor and laboratory was evaluated as the difference between paired measurements. Precision was calculated as the within-patient standard deviation based on paired values. RESULTS--Within the range of 2.0 to 3.0 INR units, the monitor yielded values that were up to 0.3 units higher on average than the laboratory values. Within the range of greater than 3.0 to 4.5 INR units, the monitor yielded values that were up to 0.5 units lower on average than the laboratory values. Seventy-five percent of paired monitor and laboratory values were within 0.7 INR units; 90% were within 0.9 units. Within-patient standard deviation was 0.23 units for the monitor and 0.19 units for the laboratory. CONCLUSIONS--The monitor differed systematically from the laboratory and was moderately less precise. The magnitude of these effects was not great, however, and accuracy was best at around INR = 3.0, the border between low and high therapeutic ranges. The clinic-based monitor is useful for patients requiring frequent surveillance of anticoagulation status.  相似文献   
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Image registration is an important step in the radiotherapy treatment planning process. It provides a method of fusing different types of diagnostic imaging information. One such application is to combine magnetic resonance spectroscopic images (MRSI) of the prostate with anatomical MRI and/or computed tomography images that are routinely used in the radiation treatment planning of prostate cancer. MRSI provides in vivo information related to the underlying metabolic activity of tissues, and can be related to the presence of cancer. However, the inflated endorectal coil required during MRS imaging poses a potential problem by deforming the prostate when it is filled with approximately 100 cm3 of air during image acquisition. This pushes the prostate superiorly/anteriorly, deforming the prostate and consequently the spectroscopic imaging data in a nonlinear manner. In this application, the coil-deformed MRS images are warped back to a non-deformed state, using a single data set. A nonlinear warping algorithm is presented to achieve this. Results indicate that the algorithm attains an accuracy of 97% (4 cm3 difference) when reproducing the total prostate volume compared to a Radiation Oncologist defined prostate volume. This difference is slightly smaller than the measured intra-operator variance of +/-1.5 cm3 (deflated coil) and the measured algorithm variance of +/-1.0 cm3. Additionally, intraprostatic nodules were used to assess the accuracy of the warping algorithm in regions inside the prostate. While choosing anatomical tie points along the external prostate surface, analysis of the nodules revealed the algorithm accuracy reduced to 63-93%.  相似文献   
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PURPOSE: If medical schools increase enrollment to meet anticipated physician shortages, more students from alternate lists will likely be accepted. This study compared the performance of alternate- and main-list students during and one year after medical school. METHOD: The authors assessed admission and performance measures for 1,188 students matriculating from 1997-2003 at the University of Kansas School of Medicine. Measures included Medical College Admission Test scores, basic and clinical science grade point averages, United States Medical Licensing Examination Step 1 and Step 2 scores, residency match information, and residency director ratings. Chi-square analyses, proportional analyses, and independent t-tests were performed. RESULTS: The results indicated that both the admission measures and performance of alternate-list students were generally lower than main-list students, but the differences were small and probably not meaningful. CONCLUSIONS: As long as the applicant pool does not substantially change from its current makeup, increasing enrollment by accepting more students from alternate lists may not adversely affect overall student performance.  相似文献   
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PURPOSE: Little is known about the effect of managed care on medical students' education. Because clerkship directors (CDs) are especially well positioned to observe any changes, this study surveyed CDs from six medical specialties about their perceptions of the effects of managed care on medical students' education. METHOD: Anonymous questionnaires were mailed to 808 CDs from departments of six medical specialties at 125 U.S. allopathic medical schools between October 1997 and March 1998. Among other questions, respondents were asked whether they had observed changes in 19 different aspects of medical students' education, whether these changes were beneficial or detrimental, and whether they believed the changes were due to managed care and/or to other factors. Results were analyzed to determine perceptions of the overall magnitude and source(s) of changes, the perceived positive versus negative effect of managed care, and whether these outcomes were statistically associated with the perceived degree of managed care's market penetration. RESULTS: Five hundred questionnaires (61.9%) were returned. For full-time and voluntary faculty teaching, faculty availability for educational administration, directors' clinical responsibilities, and quality of professional life, the most common response was that managed care had an adverse effect. For faculty's enthusiasm for teaching, directors' administrative and educational duties, and clerkship training sites, the second most common response after "not changed" was that managed care had a negative effect. The majority of respondents held negative opinions of managed care and thought that medical students did not understand it. CONCLUSIONS: CDs in six medical specialties perceived that managed care has negatively affected medical students' education. These perceptions may influence medical students' education. Measures must be taken to ensure excellent education through adequate resources and training in the context of high-quality medical care.  相似文献   
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