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41.
A survey of 40 Singapore Chinese households was performed, obtaining information on major perishable foods purchased for home consumption in the previous week, extent of home consumption (eating in), household dietary habits and housing type, the last as a measure of affluence. Eating out was very common: nine (23 per cent) households ate less than 50 per cent of meals at home. Excluding these nine households, consumption and habits were compared between more affluent and less affluent households. The more affluent households purchased more red meat/offal (P = 0.001), poultry (P = 0.002), vegetables other than green leafy (P = 0.04), fruit (P = 0.007) and eggs (P = 0.04); they also differed significantly in various dietary habits. Significant differences were also observed between English-speaking and Chinese-speaking households. The results suggest that increasing affluence may have brought about substantial dietary change in Singapore, thus meriting further study of the role of diet in changing disease patterns in Singapore.  相似文献   
42.
An influence on drug-taking behaviours of the stress-related hypothalamo-pituitary-adrenal (HPA) axis and its final hormonal mediator, corticosterone, has previously been demonstrated. A role for cortically projecting cholinergic neurons in these behaviours can also be proposed. The experiments presented here examine the effect of the drug of abuse cocaine (15 mg/kg) on the release of acetylcholine (ACh) in the cortex of freely moving rats, using the technique of in vivo microdialysis. To assess a possible modulatory influence of the HPA axis via its final hormonal mediator corticosterone, the cocaine-induced effect on cortical ACh release in intact rats was compared to that in adrenalectomized (ADX) rats, which thus lacked their endogenous source of corticosterone, and in ADX rats in which the cocaine-induced corticosterone peak and/or the basal circadian concentrations of serum corticosterone were simulated by replacement treatments. The results reported here demonstrate that cortical ACh release is greatly increased by cocaine in intact rats; ADX prolongs the return to basal levels of cortical ACh, and the chronic replacement of circadian levels of corticosterone normalizes this effect. In contrast, during the plateau period of cocaine-induced increased cortical ACh release, where no effect of ADX is evident, rats with chronic replacement of corticosterone show an attenuated cocaine-induced cortical ACh release, and the acute replacement of the cocaine-induced corticosterone secretion further attenuates this response. These results demonstrate that cocaine stimulates cortically projecting cholinergic neurons, and that the HPA hormone corticosterone modulates this interaction in a complex manner which merits further investigation.  相似文献   
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The estimation of vertebral fracture risk in individuals with suspected osteopenia is commonly based on measurements of lumbar spine bone density. The efficacy of vertebral size and deformity, as assessed by vertebral morphometry, in the prediction of fractures has been less studied. In an ex vivo investigation the regional relationships between vertebral size, vertebral deformity, bone density and compressive strength throughout the thoracolumbar spine were examined. In 16 vertebral columns (T1–L5) the bone mineral content (BMC) and bone mineral density (BMD) of each segment were measured using lateral projection dual-energy X-ray absorptiometry, and the vertebral cancellous density (VCD) and mid-vertebral cross-sectional area (CSA) measured using quantitative computed tomography. Vertebral body heights were determined from mid-sagittal CT scans, and vertical height ratios calculated for each segment. The failure load and failure stress of the isolated vertebral bodies were determined using a material testing device. Separate analyses were performed for the upper (T1–4), middle (T5–8) and lower (T9–12) thoracic, and lumbar (L1–5) segments. In all regions, failure load was strongly correlated with BMD (r=0.82–0.86), moderately correlated with VCD (r=0.60–0.71) and vertebral height (r=0.22–0.49), and poorly correlated with the height ratios (r=0.04–0.33). Failure stress was best predicted by BMD (r=0.73–0.78) and VCD (r=0.70–0.78) but was poorly correlated with all morphometric variables (r=0.01–0.33). The segmental correlations between BMD and VCD ranged fromr=0.49 tor=0.79. For all regions, BMD and VCD were included in the stepwise regression models for predicting failure load and failure stress. Either the mid-vertebral height or CSA were included in all the failure load models, while mid-vertebral height was included in only one of the failure stress models. The results suggest that vertebral deformity and size (as assessed by vertebral morphometry) make only a minor contribution to the prediction of vertebral strength additional to that provided by bone densitometry alone. The consistent regional relationships between variables appear to support the practice of global fracture risk assessment based on lumbar spine densitometry.  相似文献   
46.
Infectious intracavernous carotid artery aneurysms usually present with ophthalmoplegia and/or signs of cavernous sinus thrombosis. We report an unusual case in which a patient with AIDS presented with intractable epistaxis secondary to rupture of a giant infectious intra-cavernous carotid artery aneurysm. Culture of the aneurysm grew mycobacterium avium intracellulare (MAI). The patient was treated successfully by excision of the aneurysm and reconstruction of the internal carotid artery with a saphenous vein interposition graft.  相似文献   
47.
The nutritional status of 16 male, land-based U.S. Navy divers was assessed to collect baseline information for a cold water dive series. Diet records, blood samples, and 24-h urine collections were obtained and analyzed. The divers were deriving 17 +/- 1%, 40 +/- 2%, 32 +/- 2% of their calories from protein, carbohydrate, and fat, respectively. The remaining calories were furnished by alcohol (11 +/- 2%), an amount within the American Heart Association's guidelines. Crude fiber intake was low (3.7 +/- 0.4 g/d) whereas cholesterol (507 +/- 101 mg/d) and sodium intakes (4462 +/- 599 mg/d) were high. Mean intakes of vitamin B6 and folacin were below the Military Recommended Dietary Allowances. Mean blood concentrations and urinary excretion of minerals were normal but urinary sodium excretion was high. Results indicate that the divers' intakes of sodium and cholesterol were high, whereas intakes of complex carbohydrate and crude fiber were low. Whether these dietary patterns are suitable for extended dives, especially in cold water, remains to be determined.  相似文献   
48.
Early during rat thymus ontogeny, an important proportion of thymocytes expresses IL-2R and contains IL-2 mRNA. To investigate the role of the IL-2-IL-2R complex in rat T cell maturation, we supplied either recombinant rat IL-2 or blocking anti-CD25 mAb to rat fetal thymus organ cultures (FTOC) under several experimental conditions. The IL-2 treatment initially stimulated the growth of thymocytes and, as a result, induced T cell differentiation, but the continuous addition of IL-2 to rat FTOC, as well as the anti-CD25 administration, resulted in cell number decrease and inhibition of thymocyte maturation. These results indicate that immature rat thymocytes bear functional high- affinity IL-2R and that IL-2 promotes T cell differentiation as a consequence of its capacity to stimulate cell proliferation. Modifications in TCR alpha beta repertoire and increased numbers of NKR- P1+ cells, largely NK cells, were also observed in IL-2-treated FTOC. Furthermore, IL-2-responsiveness of different thymocyte subsets changed throughout thymic ontogeny. Immature CD4-CD8-cells responded to IL-2 in two stages, early in thymus development and around birth, in correlation with the maturation of two distinct waves of thymic cell progenitors. Mature CD8+ thymocytes maximally responded to IL-2 around birth, supporting a role for IL-2 in the increased proliferation of mature thymocytes observed in vivo in the perinatal period. Taken together, these findings support a role for IL-2 in rat T cell development.   相似文献   
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Larynx cancer risk factors   总被引:1,自引:0,他引:1  
B Zem?a  N Day  J Swiatnicka  R Banasik 《Neoplasma》1987,34(2):223-233
The larynx cancer relative risk has been evaluated (328 cases) in the stationary-native Upper Silesians (63.7%) and migrating (36.3%) male population. The particular control groups (656 men) included 418 and 238 men respectively not suffering from malignant neoplasms. The essentially higher larynx cancer incidence risk has been shown for men manual labor and exposed to the influence of various dusts, gases and vapors and other pollutants in their place of work. The increased substantial incidence risk is also true for men who smoke tobacco and are professionally exposed to the pollution. The results in regard to the consumption of raw and boiled vegetables suggest that these may be inhibitors of the neoplasmatic process in the area of larynx (although not only). The frequency of the consumption of alcohol--vodka or beer--increases the larynx cancer incidence risk both among autochthons and immigrants. Nevertheless, the data concerning the amount of alcohol consumed are less valuable here; they do not allow to establish fully reliable quantitative levels of the beer or vodka consumed. In comparison with the literature of the subject, divergent data have been obtained as far as the joint influence of drinking alcohol with simultaneous smoking of tobacco and professional exposure are concerned.  相似文献   
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