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Three methods were developed to identify a limited number of foods that are important dietary contributors of fat, dietary fiber, and vitamins A, C, and E. In the first method, foods were ranked by the amount of each nutrient supplied per person per day and the effect each food had on the relative ranking of individuals with respect to the intake of those nutrients. Foods scoring high on both scales for a given nutrient were selected as important dietary contributors of that nutrient. In the second method, foods were selected according to the mean nutrient contribution per consumer (nonconsumers of a food were eliminated from this estimation procedure). In the third method, foods were selected that contributed a relatively large percentage of the total dietary intake of a given nutrient. The three methods were applied to data from an extensive dietary questionnaire. The authors then compared the limited lists of foods identified by each method. Generally, the methods yielded similar food lists. Regression analysis was then employed to test the ability of the selected foods to predict the nutrient totals calculated from the original, more extensive dietary questionnaire. The results suggest that a limited number of foods may have strong predictive ability, but that has not been tested in any other population.  相似文献   
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Zusammenfassung Die morphologische Analyse einer Gruppenvergiftung mit Methylalkohol zeitigt Befunde, die sich in Capillar- und Parenchymschäden ä ußern.Auf Grund dieser Analyse wird das Zustandekommen der Methylalkoholvergiftung zu deuten versucht. Nach Besprechung der Toxikologie des Methylalkohol und der in der Literatur erschienenen Fälle von Methylalkoholvergiftung, die nur graduelle, aber keine grundsätzlichen Abweichungen von den eigenen Untersuchungen ergeben, wird das Schicksal des Methylalkohol im. Körper erörtert, wobei die chemischen Untersuchungsergebnisse des eigenen Materials wichtige Anhaltspunkte geben.Das Wesen der tödlich verlaufenden Methylalkoholvergiftung wird in einer Störung des Capillargefä ßsystems, also in einer unspezifischen Äußerung erblickt. Die Parenchymschäden resultieren aus derselben.Über die Ursache der Capillarstörung bei der Methylalkoholvergiftung läßt sich heute noch nichts Bestimmtes aussagen. Sicher erscheint uns zu sein, daß das bei der Oxydation entstehende Form-aldehyd die Capillaren mehr indirekt als direkt, d. h. von der Blutbahn aus schädigt. Der Rolle des Formaldehyd bei Methylalkoholvergiftung ist trotz der fehlenden Nachweisbarkeit der durch dasselbe gesetzten Schädigung eine große Bedeutung zuzumessen. Der zentral ausgelöste Tod kann nur als Folge des Formaldehyd betrachtet werden.  相似文献   
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Ho  CP; Kim  RW; Schaffler  MB; Sartoris  DJ 《Radiology》1990,176(1):171-173
Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001).  相似文献   
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Computer models were developed to simulate the effects of management technologies on populations of the American dog tick, Dermacentor variabilis (Say), principal vector of Rocky Mountain spotted fever (RMSF) in eastern North America. The technologies modeled were area-wide acaricide application, acaricide-food-baited tubes for self-treatment by small mammals, dipping of dogs in acaricides, acaricide-impregnated plastic dog collars, reduction of small mammal host populations (host management), and removal of vegetation that protects free-living tick stages (vegetative management). Submodels for each of these technologies were incorporated into a model (ADTSIM) for the population dynamics of the tick and RMSF transmission. Comparisons of simulated and observed data were used to verify reasonable accuracy of the submodels. Repetitive simulations were made to identify levels and timing of each control method (alone or combined) required to reduce tick populations below a RMSF transmission threshold of 252 unfed adults/ha. Eight to 30 acaricide applications, depending on acaricide and percentage of population treated, were needed during a 10-yr period to reduce densities of ticks below the threshold. The baited-tube method, host management, and vegetative management (depending on level and frequency of treatment) also were capable of reducing tick density below the threshold. However, acaricide-impregnated plastic dog collars did not reduce tick density below the threshold unless at least 50% of the hosts of adult ticks were domestic dogs. Integrated strategies were developed for management of ticks and RMSF in six selected states. These strategies reduced numbers of human cases of RMSF 90% or more by year 20 by maintaining tick densities between 100 and 252 unfed adults/ha.  相似文献   
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Adenomyoepithelioma is a rare disorder characterised by simultaneous proliferation of ductal epithelium and myoepithelial cells. It is more common in salivary glands or skin, and only rarely found in breast tissue. Adenomyoepithelioma of the breast was first described in 1970 by Hamperl.1 Since then, approximately 55 cases have been described in the literature; the largest review, by Tavassoli in 1991, reported 27 of these cases.2 Because of the small number of cases reported, the natural history of adenomyoepithelioma of the breast remains uncertain. We report a further case which was treated by local excision, and follow-up for two years has revealed no evidence of local recurrence or metastatic spread.  相似文献   
100.
The T(c)-cell response to ectromelia virus infection was studied in BALB/c-H-2(db) mice which carry a loss mutation in the H-2D region that results in the absence from cell surfaces of a molecule (D’) bearing certain public H-2 specificities. When infected, these mice showed a poor response of T(c) cells that recognize H-2D(d) plus virus-specific determinants on infected macrophage targets, but gave a normal response to H-2K d plus virus-specific antigens. However, their own infected macrophages do display wild-type antigenic patterns involving virus and H-2D(d) since they were killed as efficiently as wild-type (BALB/c,H- 2(d))-infected cells by T(c) cells specific only for H-2D(d) plus viral antigens. When tested in vitro, infected BALB/c-H-2(db) cells stimulated a poor T(c)-cell response to H-2D plus virus-specific antigens, but stimulated a normal response (in comparison with infected BALB/c macrophages) to H-2K(d) plus viral antigens. Uninfected BALB/c-H-2(db) cells stimulated a normal T(c)-cell response to minor H antigens or trinitrophenyl in association with H-2D(d), thus suggesting that the defective response to infection may reside in a failure of the relevant H-2D(d) antigens of mutant cells to physically associate with viral antigens. Close association of viral and H-2D-coded molecules was also suggested by ability of specific anti-H-2K or -H-2D to partially block T(c)-cell-mediated lysis of infected targets. These results were interpreted to mean that H-2Dd-dependent, virus- immune T(c) cells recognized an antigenic pattern consisting of virus- specific and H-2D(d) determinants with the latter borne on an H-2D molecule carrying serologically-defined H-2D(d) private specificities. A second H-2D(d)-coded molecule (D’) was not required for recognition and lysis by activated T(c) cells, but was apparently necessary for efficient stimulation of precursor T(c) cells, perhaps by promoting appropriate physical association of viral and H-2D(d) molecules.  相似文献   
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