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141.
142.
Xenohormesis解释了为何植物受环境胁迫后产生的次生代谢产物能提高取食动物的胁迫耐受性与生存机会,认为在自然选择压力下动物保留着感知这些胁迫信号分子的能力,从而激活进化保守性的细胞应激响应机制,提高逆境适应力.该文在介绍Xenohormesis效应概念与机制,分析总结植物与昆虫及人类的Xenohormesis效应关系的基础上,以人参为例阐述了中药Xenohormesis效应,认为借鉴Xenohormesis理论能从进化与生态角度理解中药生物效应的本质,对中药现代化研究具重要价值. 相似文献
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Yu Diana Sanders Lynda M. Davidson III George W. R. Marvin Martha J. Ling Teck 《Pharmaceutical research》1988,5(7):457-462
Vehicle effects on the percutaneous absorption of nicardipine base, nicardipine hydrochloride, ketorolac acid, and ketorolac tromethamine were determined using the rhesus monkey as an in vivo model for human skin penetration. Vehicles investigated included blends of propylene glycol, trimethylene glycol, ethanol, Azone, Tween 20, water, and long-chain fatty acids. Formulations were prepared such that the compound dose, application area, and percentage saturation of the compound in the vehicle were held constant. Variations in absorption of the compounds were therefore attributable to vehicle effects. Each formulation was applied to three monkeys for a period of 24 hr using 10 Hill Top Chambers. Plasma samples were taken at appropriate intervals for 36 to 48 hr. The results indicated that trimethylene glycol and Tween 20 did not enhance absorption of the test compounds despite claims by other investigators. Azone and ethanol provided moderate enhancement of both the rate and the extent of absorption, while long-chain fatty acids in combination with propylene glycol significantly enhanced penetration. In general, higher fluxes were observed with the more lipophilic compounds nicardipine base and ketorolac acid as compared to the hydrochloride and tromethamine salts. 相似文献
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146.
After learning a light-cued, go-no go successive discrimination to criterion, male Sprague-Dawley rats received 0, 5, or 10 mg/kg chlordiazepoxide on six performance sessions, followed by two drug-recovery (saline) sessions. Chlordiazepoxide impaired discrimination performance in a dose-dependent manner, with animals in the 5 mg/kg dose condition demonstrating tolerance to the drug after two performance sessions. The degree of discrimination impairment in both drug dose conditions paralleled an increase in responding during no-go phases of the performance task. These findings are consistent with a disinhibitory hypothesis of performance impairment and suggest that CDP-drugged animals have difficulty in withholding incorrect responses.These data were presented at the Annual Meeting of the Psychonomic Society, San Antonio, Texas, 1984 相似文献
147.
The present study aimed to characterize the chlorogenic acid (ChlA) capacity to reverse the toxic effects induced by ochratoxin A (OTA) in a subacute toxicity test in rats. Male Wistar rats were fed orally by gavage for 28 days with OTA (0.4 mg/kg bw/day), ChlA (5 mg/kg bw/day) or the combination OTA (0.4 mg/kg bw/day) + ChlA (5 mg/kg bw/day). No deaths, no decrease in feed intake or body weight in any experimental group were recorded. The negative control group and the animals treated with ChlA alone showed no changes in any parameters evaluated. In OTA-treated group significant changes such as decrease in urine volume, proteinuria, occult blood, increase in serum creatinine values; decrease in absolute and relative kidney weight and characteristics histopathological lesions that indicated kidney damage were observed. However, limited effect on oxidative stress parameters were detected in kidneys of OTA-treated group. Animals treated with the combination OTA + ChlA were showed as negative control group in the evaluation of several parameters of toxicity. In conclusion, ChlA, at given concentration, improved biochemical parameters altered in urine and serum and pathological damages in kidneys induced by OTA exposure, showing a good protective activity, but not by an apparent antioxidant mechanism. 相似文献
148.
Quality of Life of People with Epilepsy: A European Study 总被引:18,自引:18,他引:18
Gus A. Baker Ann Jacoby Deborah Buck Carlos Stalgis † Dominique Monnet† 《Epilepsia》1997,38(3):353-362
Summary: Purpose: To study the impact of epilepsy and its treatment on people with epilepsy in Europe. We therefore aimed to collect data from as many countries as possible.
Methods: Clinical and demographic details and information about psychosocial functioning was collected using self-completed questionnaires mailed to members of epilepsy support groups.
Results: Quality of life data was collected from >5,000 patients living in 15 countries in Europe. Over a third of all respondents had frequent seizures, and a fifth believed that their seizures were not well enough controlled by antiepileptic medication. Reported levels of side effects from medication were high. A significant number of respondents reported changing their medication because of side effects or poor control. Respondents reported that epilepsy and its treatment had a significant impact on a number of different aspects of their daily lives. Half of all respondents felt stigmatised by their epilepsy. There were significant differences by seizure type and frequency in the way respondents scored on measures of the perceived impact of their condition, the stigma associated with it and their health status as measured by a generic scale, the SF36.
Conclusions: This study confirms the findings of previous smaller-scale studies that reducing side effects and achieving better control of seizures are key to improving the quality of life of people with epilepsy, as is reducing the stigma and handicap associated with it. 相似文献
Methods: Clinical and demographic details and information about psychosocial functioning was collected using self-completed questionnaires mailed to members of epilepsy support groups.
Results: Quality of life data was collected from >5,000 patients living in 15 countries in Europe. Over a third of all respondents had frequent seizures, and a fifth believed that their seizures were not well enough controlled by antiepileptic medication. Reported levels of side effects from medication were high. A significant number of respondents reported changing their medication because of side effects or poor control. Respondents reported that epilepsy and its treatment had a significant impact on a number of different aspects of their daily lives. Half of all respondents felt stigmatised by their epilepsy. There were significant differences by seizure type and frequency in the way respondents scored on measures of the perceived impact of their condition, the stigma associated with it and their health status as measured by a generic scale, the SF36.
Conclusions: This study confirms the findings of previous smaller-scale studies that reducing side effects and achieving better control of seizures are key to improving the quality of life of people with epilepsy, as is reducing the stigma and handicap associated with it. 相似文献
149.
目的 研究smad2/3在沙鼠脑缺血再灌注脑内表达及氟桂利嗪干预后对其表达的影响.方法 35只沙鼠随机分假手术组、缺血再灌注组和氟桂利嗪治疗组3组,采用夹闭双侧颈总动脉制作沙鼠脑缺血再灌注模型,于缺血10 min再灌注1 d、3 d、7 d各时间点处死动物,用免疫组化方法检测各组沙鼠脑内smad2/3的表达情况.结果 假手术组沙鼠脑内smad2/3弱阳性表达,而缺血再灌注1 d,3 d,7 d后沙鼠脑内呈阳性或强阳性表达,两者比较差异有统计学意义(P<0.01);氟桂利嗪治疗组smad2/3的表达低于缺血再灌注组,2组比较差异有统计学意义(P<0.05).结论 沙鼠脑内有smad2/3表达,脑缺血再灌注后,脑内smad2/3表达上调;氟桂利嗪干预后,其表达下调. 相似文献
150.