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21.
蜂胶提取物对小鼠胸腺肽合成的影响 总被引:2,自引:0,他引:2
目的:研究蜂胶乙醇提取物黄酮(EEP)对小白鼠衰老过程中胸腺肽合成量的影响。方法:垂直板电泳法。结果:EEP可增加小鼠胸腺肽的合成量。结论:EEP可增强小鼠的免疫力。具有抗衰老作用。 相似文献
22.
J. Scott Tonigan 《Alcoholism, clinical and experimental research》2007,31(S3):55s-56s
The statistical search for mechanisms of change involves multiple inferential tests, ones that generally follow a fixed sequence designed to demonstrate mediation. While there are several popular approaches to conducting such tests, e.g., SEM and MRA, the inflated Type I error rate problem associated with conducting these tests has received little, if any, attention. This paper offers 2 solutions to avoid committing Type I errors associated with mediational tests. Most straightforward, investigators may choose to use a Bonferroni adjustment. In contrast, a design-based approach can be used that tests rival explanations for the observed effects. Examples drawn from addiction research are provided. 相似文献
23.
目的:探讨复方葡萄籽提取物(GSE)对化学性肝损伤的预防和治疗作用。方法:用小鼠建造四氯化碳肝损伤和乙醇肝损伤模型,观察乙醇灌胃前预先给予复方GSE及乙醇或四氯化碳灌胃后再给予复方GSE后小鼠血清谷丙转氨酶(ALT),肝细胞超氧化物歧化酶(SOD)、谷光甘肽(GSH)、丙二醛(MDA)。结果:预先给予GSE可增强SOD活性,防止乙醇导致的肝GSH减少,有效降低小鼠血清ALT和肝细胞MDA上升程度,在乙醇或四氯化碳灌胃后再给予复方GSE,也可降低小鼠血清中ALT和肝细胞脂质过氧化产物。结论:复方GSE对乙醇肝损伤有预防和治疗作用。对四氯化碳肝损伤也有一定治疗作用。 相似文献
24.
25.
Alcohol is an important risk factor for human oesophageal cancer. There is evidence from epidemiological studies that some
specific alcoholic drinks, e.g. Calvados apple brandy, are associated with a greater risk than others. Alcohol induces cytochrome
P450 2E1 (CYP2E1) and the hypothesis was tested that different alcoholic beverages, containing a variety of alcoholic compounds,
could differentially induce expression of cytochrome P450 enzymes. Twelve groups of five rats each were treated for 3 days
with different alcoholic beverages (ethanol alone, whisky, farm-produced or commercial Calvados brandy, beer, cider, wine)
adjusted to 4, 10 or 20% of ethanol in drinking water. Immunoblotting using a monoclonal antibody specific for rat CYP2E1
revealed a single protein band in liver microsomes. Densitometric quantitation of microsomal proteins demonstrated a significant
two-, three- and sixfold increase in band intensity after treatment with ethanol concentrations of 4, 10 and 20% respectively,
compared to control rats drinking water alone. There was a dose-dependent increase in liver microsomal metabolism of CYP2E1
substrates (para-nitrophenol and dimethylnitrosamine) in ethanol-treated rats. However, there were no significant differences
in the level of CYP2E1 protein or enzymatic activity between the different alcoholic beverages at the same ethanol concentration.
There was a slight increase in hepatic CYP1A-related enzymatic activities in the alcohol-treated rats compared to the controls,
but no difference between the treated groups either with dose of ethanol or type of beverage. These data show that induction
of CYP2E1 with acute alcohol treatment is predominantly determined by the ethanol content of the beverage.
Received: 10 February 1997 / Accepted: 26 May 1997 相似文献
26.
Kalevi Laitinen David Sinclair Maria Nurmi Reija Hietala Heikki Kröger Kalervo Kiianmaa Mikko Salaspuro 《Alcoholism, clinical and experimental research》1992,16(5):875-880
Previous work has shown that calcitonin inhibits eating by rats and that it affects several neurotransmitter systems suspected to play a role in alcohol consumption. The present study was an initial test of whether calcitonin does affect voluntary alcohol consumption by male Wistar rats with prolonged alcohol experience. Calcitonin (20 IU/kg) or saline was injected subcutaneously on 10 consecutive days when the rats (n = 20) had continual access to 10% (v/v) ethanol solution, and to food and water. Using a cross-over design, the effects of 40 IU/kg calcitonin vs. saline were then examined in a second 10-day treatment period. Similar patterns of effects were obtained with both calcitonin doses, but the patterns differed with alcohol, food, and water intake. Alcohol drinking showed biphasic changes with both doses, producing highly significant Treatment x Day interactions (p < 1E-10 and p = 6E-7): it was significantly reduced on the first day of calcitonin treatment and significantly increased on the last few days. Food intake was reduced on all calcitonin days although most markedly on the first. Water drinking was not altered on the first calcitonin day, but was greatly increased on the second, then gradually returned toward the baseline. In a second experiment, the animals were switched to 1 hr of alcohol access per day, and calcitonin (20 IU/kg) was administered periodically to one group 4 hr before the alcohol access. Alcohol drinking was significantly reduced in all cases when the calcitonin injection was preceded by at least 1 day without calcitonin.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
27.
This study attempts to demonstrate the existence of allergic contact dermatitis from grass, and to develop a patch test series to screen patients with grass intolerance. 6 common grass species from lawns and military training areas were collected. Solvent extracts of polar. non-polar and volatile fractions were prepared and used for patch testing in 20 control subjects and 46 patients with a history of grass intolerance. The 20 control had negative responses to patch testing. 5 out of 46 patients had positive patch tests to Axonopus compressus (carpet grass). Ischaenmum muticum (sea-shore centipede grass). Imperata evlindrica (lalang). Panicum maximum (Guinea grass) and Pennisetum purpureum (elephant grass). Reactions to the non-polar fraction for all 5 species were noted. This study demonstrates the existence of allergic contact dermatitis from various common species of grass. In our series, this is seen in 11% of those with a history of grass intolerance. 相似文献
28.
P. Lombrail T. Lang P. Degoulet F. Aimee C. Devries C. Fouriaud M. C. Jacquinet-Salord 《European journal of epidemiology》1988,4(3):371-376
Alcohol consumption and glycosuria were found to be associated (p < 0.001) in a population of 6571 salaried employees who underwent a systematic examination. The prevalence of glycosuria was found to range from 1.3% among 2609 non-drinkers to 5% among 816 heavy drinkers (six glasses or more of alcoholic beverage daily). This association was still significant after adjustement for age, sex and body mass index. Similarly, a positive association was observed between fasting glycemia and alcoholic intake in a subgroup of 998 subjects when such a result was available (p < 0.05). 相似文献
29.
Male Wistar rats bearing intracerebroventricular (ICV) cannulae and with simultaneous access to 6% ethanol and water were
subjected to adrenalectomy (ADX) or sham surgery. ADX decreased ethanol intake. Starting a few days later, the animals received
ICV infusions with 100 μg corticosterone acetate (CORT) with 2-to 3-day intervals for 2 weeks. ICV CORT, but not SC CORT at
the same dose, restored ethanol consumption in ADX rats to preoperative levels, whereas vehicle infusions (propylene, glycol)
did not. Adrenally intact animals, which normally consumed moderate amounts of ethanol (≈0.5 g/kg per day), also showed a
robust effect of ICV infusions of CORT, whereas this facilitatory effect was not observed in high consumers (≈3.0 g/kg per
day). The suppressive effect of ADX on ethanol intake was not reproduced by concurrent and repeated ICV infusions of intracellular
mineralocorticoid (RU 28318) and glucocorticoid (mifepristone) receptor blockers. It is concluded that CORT stimulates alcohol
consumption by acting in the brain, probably by way of neuronal membrane mechanisms. 相似文献
30.
Adolf Pfefferbaum Edith V. Sullivan Margaret J. Rosenbloom Paula K. Shear Daniel H. Mathalon Kelvin O. Lim 《Psychiatry Research: Neuroimaging》1993,50(4):257-274
This cross-sectional study used a semi-automated analysis technique to quantify regional brain cerebrospinal fluid (CSF) volumes derived from computed tomography (CT) in 84 healthy men ranging from 21 to 82 years of age and 28 patients meeting Research Diagnostic Criteria for alcohol dependence. The goals were to replicate an earlier CT study of an independent sample of alcoholic and control subjects (Pfefferbaum et al., 1988a; Zipursky et al., 1988) and to compare CT assessments of brain changes with magnetic resonance imaging (MRI) assessments made in the same alcoholic patients (Pfefferbaum et al., 1992). Regional brain changes associated with normal aging were derived by regression analysis, using CT data collected from the healthy control subjects. As in the earlier CT study and in the concurrent MRI study, ventricular and sulcal CSF volumes in alcoholic patients were greater than would be expected for their age. Furthermore, the present CT study replicated the previous CT and MRI findings of a positive relationship between age and CSF volume enlargement in alcoholic patients over and above the normal age-related increase in CSF volume, suggesting greater vulnerability of the aging brain to alcohol. Comparison of CT-and MRI-derived estimates of ventricular and cortical sulcal volume revealed high correlations (>0.80). MRI and CT produced similar absolute ventricular volumes, while MRI produced larger sulcal volume estimates than did CT. The difference in sulcal volume estimate may be due to differences between CT and MRI in slice thickness and sensitivity to partial volume effects. 相似文献