全文获取类型
收费全文 | 4030篇 |
免费 | 283篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 74篇 |
妇产科学 | 77篇 |
基础医学 | 559篇 |
口腔科学 | 67篇 |
临床医学 | 375篇 |
内科学 | 931篇 |
皮肤病学 | 81篇 |
神经病学 | 268篇 |
特种医学 | 130篇 |
外科学 | 552篇 |
综合类 | 73篇 |
一般理论 | 2篇 |
预防医学 | 326篇 |
眼科学 | 237篇 |
药学 | 285篇 |
中国医学 | 29篇 |
肿瘤学 | 242篇 |
出版年
2024年 | 10篇 |
2023年 | 54篇 |
2022年 | 128篇 |
2021年 | 206篇 |
2020年 | 152篇 |
2019年 | 188篇 |
2018年 | 229篇 |
2017年 | 151篇 |
2016年 | 173篇 |
2015年 | 160篇 |
2014年 | 189篇 |
2013年 | 256篇 |
2012年 | 370篇 |
2011年 | 361篇 |
2010年 | 223篇 |
2009年 | 178篇 |
2008年 | 255篇 |
2007年 | 244篇 |
2006年 | 192篇 |
2005年 | 132篇 |
2004年 | 122篇 |
2003年 | 104篇 |
2002年 | 65篇 |
2001年 | 16篇 |
2000年 | 18篇 |
1999年 | 15篇 |
1998年 | 14篇 |
1997年 | 9篇 |
1996年 | 14篇 |
1995年 | 8篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1987年 | 3篇 |
1985年 | 3篇 |
1984年 | 6篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 5篇 |
1980年 | 5篇 |
1979年 | 8篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1971年 | 4篇 |
排序方式: 共有4350条查询结果,搜索用时 0 毫秒
31.
Mohsen Maddah Razieh Shoyooie Zahra Akbarian Maryam RostamNejad Mehdi Soleymani 《Mediterranean journal of nutrition and metabolism》2013,6(1):69-72
This study aimed to investigate dietary supplement use among Iranian adults in northern Iran. A cross-sectional study was undertaken on randomly selected men and women in Guilan province, northern Iran. The study population was parents of children and adolescents studying in schools. Totally, 1,425 women and 676 men were studied and data on age, body weight, height, educational level, and supplement use was gathered using a self-administrated questionnaire. These data showed that supplement use was related to sex, body mass index, and educational levels in both sexes. Most common supplements used in this population were Iron, calcium, multivitamin/multiminerals and fish oils. These results showed that 13.3, 3.4, 2.2, and 1.1 % of the study men used iron, calcium, multivitamin/multimineral, and fish oil, respectively. In women, 27.1, 10.7, 5.1, and 5.5 % used Iron, calcium, multivitamin/multimineral, and fish oil, respectively. More educated men and women and those with more healthy weight were more likely to use any dietary supplement than the less educated and overweight/obese men and women. This study showed that iron was the most common dietary supplement in this study middle aged Iranians. Using the other supplements was mostly related to age, educational level, and body weight status in this population. These data indicated that dietary supplement use was inversely related to some health-related behaviors and socioeconomic factors. 相似文献
32.
Matthieu Heidet Abdel Abdel Wahab Vahid Ebadi Yann Cogne Charlotte Chollet-Xemard Mehdi Khellaf 《The Journal of emergency medicine》2019,56(3):279-281
Background
Bodybuilding is a demanding sport, which requires high-volume, high-resistance weight training and augmented nutritional intake, toward an increase of overall body muscle mass accompanied by an overall decrease of body fat percentage and mass. Among bodybuilders, the use of various legal and illegal supplements is common. These supplements may be naturally occurring or man-made.Case Report
We discuss the case of a 30-year-old male bodybuilder presenting with coma due to severe hypoglycemia from unknown cause, necessitating iterative glucose infusions, which was subsequently found to be related to cryptic insulin injections.Why Should an Emergency Physician Be Aware of This?
In strength athletes, especially amateurs, the recourse to performance-enhancement drugs (e.g., insulin) is frequent. Beyond the specificity of care required for surreptitious insulin intoxication, emergency physicians should be alert to the possibility that exogenous insulin has been injected for use as an ergogenic aid by bodybuilders and others seeking to increase their body muscle mass when they encounter a patient with a decreased level of consciousness and treatment-refractory hypoglycemia. Moreover, in case of suspicion of such intoxication, the use of other illegal supplements should be screened, due to potentially associated risks of complication. 相似文献33.
34.
Mehdi Mogharnasi Hossein TaheriChadorneshin Seyed Amin Papoli-Baravati Asma Teymuri 《Disability and health journal》2019,12(1):29-34
Background
As a recently discovered adipokine, nesfatin-1 is conducive to insulin sensitivity, lipid profile, energy balance, and probably obesity.Objective
The aim of the present study was to investigate the effect of upper-body resistance exercise training (RET) on nesfatin-1 levels, insulin resistance, lipid profile, and body composition in obese paraplegic men.Methods
Twenty obese paraplegic men were randomly assigned into control and upper-body RET groups. Upper-body RET was performed for 8 weeks, 3 sessions per week at an intensity corresponding to 60–80% maximum amount of force that can be generated in one maximal contraction in 5 stations (bench press, seated rows, sitting lat pulldown, arm extension, and arm curls). Body fat percentage was determined according to 4-sites skinfold protocol of Durnin and Womersley and Siri equation. Obesity for spinal cord injury patients in the current study was set at BMI >22?kg/m2. Data were statistically analyzed by paired and independent t-test (P?<?0.05).Results
We found significant improvements in serum levels of nesfatin-1 (21.13%), insulin sensitivity (8.95%), and high-density lipoprotein (10.87%). Other lipid profile markers, i.e. low-density lipoprotein (4.32%), cholesterol (8.20%), and triglyceride (15.10%) reduced significantly after upper-body RET. Moreover, upper-body RET led to a significant reduction in body mass index (2.36%), body fat percentage (2.79%), and waist-to-hip ratio (2.40%).Conclusion
Upper-body RET improved insulin sensitivity, lipid profile, and body composition in paraplegic men. Serum nefastin-1 may be a potential marker of success in weight management in this population. 相似文献35.
36.
37.
38.
Cataract, opacification of the lens, is one of the commonest causes of loss of useful vision, with an estimated 16 million people worldwide affected. Several risk factors have been identified in addition to increasing age--genetic composition, exposure to ultraviolet light, and diabetes. However, no method to halt the formation of a cataractous lens has been shown to be effective. Nevertheless, advances in surgical removal of cataracts, including small-incision surgery, use of viscoelastics, and the development of intraocular lenses, have made treatment very effective and visual recovery rapid in most cases. Despite these advances, cataract continues to be a leading public-health issue that will grow in importance as the population increases and life expectancy is extended worldwide. 相似文献
39.
40.
Saba S Mathier MA Mehdi H Liu T Choi BR London B Salama G 《Journal of cardiovascular electrophysiology》2008,19(2):197-202
Introduction: Myocardial infarction (MI) disrupts electrical conduction in affected ventricular areas. We investigated the effect of MI on the regional voltage and calcium (Ca) signals and their propagation properties, with special attention to the effect of the site of ventricular pacing on these properties.
Methods: New Zealand White rabbits were divided into four study groups: sham-operated (C, n = 6), MI with no pacing (MI, n = 7), MI with right ventricular pacing (MI + RV, n = 6), and MI with BIV pacing (MI + BIV, n = 7). At 4 weeks, hearts were excised, perfused, and optically mapped. As previously shown, systolic and diastolic dilation of the LV were prevented by BIV pacing, as was the reduction in LV fractional shortening.
Results: Four weeks after MI, optical mapping revealed markedly reduced action potential amplitudes and conduction velocities (CV) in MI zones, and these increased gradually in the border zone and normal myocardial areas. Also, Ca transients were absent in the infarcted areas and increased gradually 3–5 mm from the border of the normal zone. Neither BIV nor RV pacing affected these findings in any of the MI, border, or normal zones.
Conclusions: MI has profound effects on the regional electrical and Ca signals and on their propagation properties in this rabbit model. The absence of differences in these parameters by study group suggests that altering the properties of myocardial electrical conduction and Ca signaling are unlikely mechanisms by which BIV pacing confers its benefits. Further studies into the regional, cellular, and molecular benefits of BIV pacing are therefore warranted. 相似文献
Methods: New Zealand White rabbits were divided into four study groups: sham-operated (C, n = 6), MI with no pacing (MI, n = 7), MI with right ventricular pacing (MI + RV, n = 6), and MI with BIV pacing (MI + BIV, n = 7). At 4 weeks, hearts were excised, perfused, and optically mapped. As previously shown, systolic and diastolic dilation of the LV were prevented by BIV pacing, as was the reduction in LV fractional shortening.
Results: Four weeks after MI, optical mapping revealed markedly reduced action potential amplitudes and conduction velocities (CV) in MI zones, and these increased gradually in the border zone and normal myocardial areas. Also, Ca transients were absent in the infarcted areas and increased gradually 3–5 mm from the border of the normal zone. Neither BIV nor RV pacing affected these findings in any of the MI, border, or normal zones.
Conclusions: MI has profound effects on the regional electrical and Ca signals and on their propagation properties in this rabbit model. The absence of differences in these parameters by study group suggests that altering the properties of myocardial electrical conduction and Ca signaling are unlikely mechanisms by which BIV pacing confers its benefits. Further studies into the regional, cellular, and molecular benefits of BIV pacing are therefore warranted. 相似文献