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21.
Every year, analysts in the Health Care Financing Administration present figures on what our Nation spends for health. As the result of a comprehensive re-examination of the definitions, concepts, methods, and data sources used to prepare those figures, this year's report contains new estimates of national health expenditures for calendar years 1960 through 1988. Significant changes have been made to estimates of spending for professional services and to estimates of what consumers pay out of pocket for health care. In the first article, trends in use of and expenditure for various types of goods and services are discussed, as well as trends in the sources of funds used to finance health care. In a companion article, the benchmark process is described in more detail, as are the data sources and methods used to prepare annual estimates of health expenditures.  相似文献   
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Objective: The objective of this study was to analyze whether faculty ratings of residents, using the mini-CEX oral exam format, differed in stringency or were influenced by the clinical setting. It also sought to learn whether the examiners were satisfied with the format.Method: A mini-CEX encounter consisted of a single faculty member observing a resident conduct a focused history and physical examination in an inpatient, outpatient, or emergency room setting. After asking the resident for a diagnosis and treatment plan, the faculty member rated the resident and provided educational feedback. The encounters were intended to be short and occur as a routine part of the training, so each resident would be evaluated on many occasions by different faculty.Sample: Sixty-four attending physicians evaluated residents from five internal medicine training programs; data were analyzed for 355 mini-CEX encounters involving 88 residents.Results: There were not large differences among the examiners in their ratings. Moreover, there were not great differences among the ratings in terms of the training program with which the examiner was associated, the setting of the mini-CEX, or the nature of the patient. The examiners were generally satisfied with the format and their level of satisfaction was correlated with the residents' perceptions of the format.Conclusion: The mini-CEX adapts itself to a broad range of clinical situations, and these results show that it should produce roughly comparable scores over examiners and settings. This makes it a worthwhile device for evaluation at the local level.This revised version was published online in September 2005 with corrections to the Cover Date.  相似文献   
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Health care costs are rising rapidly, and surgeons can play a role in limiting costs of operations. Of the 600,000 cholecystectomies performed each year in the United States, approximately 80% are performed with laparoscopic technique. The purpose of this study was to compare the costs of reusable vs disposable instruments used during laparoscopic cholecystectomy. The costs to the hospital of reusable and disposable instruments were obtained. Instruments studied were the Veress needle, trocars and sleeves (two 10 mm and two 5 mm), reducers, clip appliers, and clips. In addition, the costs of sterilization and sharpening for reusable instruments were calculated. The cost of reusable instruments was based on an assumed instrument life of 100 cases. Data from three private hospitals and a Canadian university hospital were collected and examined. Data from the four hospitals revealed that the costs of reusable instruments per case were $46.92–$50.67. The comparable costs for disposable instruments were $385.28–$515.48. The advantage was thus $330.00–$460.00 per case. Theoretical advantages of disposable instruments such as safety, sterility, and better efficiency are not borne out in literature review. In addition, the environmental impact of increased refuse from disposable instruments could not be exactly defined. With the consideration of significant cost savings and the absence of data demonstrating disadvantages of their use, reusable instruments for laparoscopic cholecystectomy are strongly recommended.  相似文献   
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BACKGROUND: Nitrogen-containing bisphosphonates have been shown to be effective for the treatment of osteoporosis and Paget's disease of bone. Unfortunately, these drugs also have the capacity to irritate the upper gastrointestinal mucosa. In this study we investigated the ability of alendronate and pamidronate to directly damage the gastric epithelium and attempted to determine whether these drugs caused injury through gastric microcirculatory alterations. METHODS: An ex vivo gastric chamber model was used. Effects of topically applied alendronate and pamidronate on transmucosal potential difference and epithelial integrity (histology) were determined. Also, the effects of agents capable of preventing microvascular injury in the stomach (PGE2 and two nitric oxide donors) were examined for their ability to prevent gastric injury induced by the two N-bisphosphonates. RESULTS: Alendronate and pamidronate caused a concentration-dependent decrease in transmucosal potential difference, widespread epithelial injury and infiltration of neutrophils into the mucosa. PGE2 and the two nitric oxide donors did not prevent the changes in potential difference or the epithelial injury, but did reduce neutrophil infiltration. Significant release of PGE2 into the lumen was observed following application of the two bisphosphonates, but neither drug altered mucosal blood flow. CONCLUSIONS: These results suggest that these N-bis- phosphonates directly damage the gastric epithelium independent of actions on the microvasculature.  相似文献   
25.
Flow cytofluorimetry and statmokinetic method were used to study the circadian rhythm of bone marrow proliferation in Pliss' lymphosarcoma-bearing and intact rats. These data were compared to those obtained in the study of the mitotic activity of the bone marrow in cancer patients. It was found that, already at early stage, tumor affected the circadian rhythm of bone marrow proliferation, reducing the amplitude of oscillations. A model simulating formation of the circadian rhythm of the bone marrow was suggested basing on the possibility to arrest cells at the end of G1 phase. The rate of transition of G1 cells to S phase was determined not only by endogenous "set-points" of the rhythm which formed the basic wave of proliferation but also by conditions of animal upkeep.  相似文献   
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To keep pace with increasing competition, the private physician is encouraged to consider a patient education program as a marketing tool. Meeting the educational needs of patients is presented as an opportunity to create a trusting environment in the practice, enhance the doctor-patient relationship, and increase the active role of the patient in the health care process. A management model is proposed for successfully planning, organizing, staffing, leading, and controlling the patient education program.  相似文献   
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Summary The main dolichol diphosphate-bound oligosaccharides present in primary cultures of both normal and tumor mouse mammary epithelial cells had the same size, yielded the same pattern after acetolysis and paper chromatography, had the same number of mannose residues susceptible to-mannosidase degradation, and were composed of the same monosaccharide residues. This is the first demonstration that normal and tumor mammary cells have dolichol diphosphate-bound oligosaccharides with very similar, if not identical, structures. These compounds are intermediates in the synthesis of asparagine-linked oligosaccharides. On the other hand, normal and tumor cells showed differences in the specific activities of the enzymes involved in the transfer of the distal monosaccharides from the sugar nucleotides to glycoproteins. Sialyl- and fucosyl-transferases were elevated and galactosyl- and N-acetylglucosaminyltransferases were diminished in mammary tumor cells. The intact tumor cells showed an increased fucosylation of glycoproteins of the asparagine-linkage type. Address for reprints: Roberto L. Ceriani, M.D., Ph.D., Bruce Lyon Memorial Research Laboratory, Children's Hospital Medical Center, 51st and Grove Streets, Oakland, CA 94609, USA.  相似文献   
30.
The world's oceans are polluted by a continuous inflow of plastic. Plastic fragments finally into microplastic, which can be taken up, for example by plankton, and subsequently by the entire ocean food web. An approach to reduce plastic pollution constitutes the accelerated microplastic degradation in marine environments. TiO2 (anatase) is commonly used as an oxidative photocatalyst and well known to catalyze the degradation of organic compounds upon UV irradiation.In this study, a selective activation of TiO2 (anatase) particles encapsulated by Ca- or Sr-polyphosphate is presented. The TiO2 polyphosphate core-shell particles are envisaged as additives in plastic products. The highly concentrated cations from seawater, viz. Na+ and Mg2+, displace the Ca2+ or Sr2+ cations from the polyphosphate shell. As a result, the polyphosphate coating dissolves and thus the photocatalytically active TiO2 core is released. The stability of the TiO2 polyphosphate particles in potable water and the seawater activated disintegration of methylene blue, methyl methacrylate, terephtalic acid, and poly(vinyl alcohol) was shown. It has been demonstrated, that the sweetwater stable polyphosphate coating degrades in the presence of seawater, which could be monitored by the activation of the TiO2 (anatase) photocatalyst.  相似文献   
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