全文获取类型
收费全文 | 6067篇 |
免费 | 514篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 170篇 |
儿科学 | 255篇 |
妇产科学 | 168篇 |
基础医学 | 851篇 |
口腔科学 | 84篇 |
临床医学 | 653篇 |
内科学 | 1071篇 |
皮肤病学 | 49篇 |
神经病学 | 577篇 |
特种医学 | 174篇 |
外科学 | 656篇 |
综合类 | 105篇 |
一般理论 | 20篇 |
预防医学 | 686篇 |
眼科学 | 105篇 |
药学 | 420篇 |
肿瘤学 | 547篇 |
出版年
2023年 | 33篇 |
2022年 | 53篇 |
2021年 | 136篇 |
2020年 | 112篇 |
2019年 | 158篇 |
2018年 | 184篇 |
2017年 | 121篇 |
2016年 | 153篇 |
2015年 | 162篇 |
2014年 | 213篇 |
2013年 | 282篇 |
2012年 | 464篇 |
2011年 | 418篇 |
2010年 | 211篇 |
2009年 | 174篇 |
2008年 | 321篇 |
2007年 | 311篇 |
2006年 | 306篇 |
2005年 | 321篇 |
2004年 | 294篇 |
2003年 | 250篇 |
2002年 | 215篇 |
2001年 | 102篇 |
2000年 | 99篇 |
1999年 | 103篇 |
1998年 | 62篇 |
1997年 | 32篇 |
1996年 | 36篇 |
1995年 | 35篇 |
1994年 | 28篇 |
1992年 | 72篇 |
1991年 | 82篇 |
1990年 | 69篇 |
1989年 | 70篇 |
1988年 | 76篇 |
1987年 | 74篇 |
1986年 | 75篇 |
1985年 | 55篇 |
1984年 | 54篇 |
1983年 | 45篇 |
1982年 | 43篇 |
1980年 | 37篇 |
1979年 | 51篇 |
1978年 | 29篇 |
1977年 | 31篇 |
1976年 | 31篇 |
1975年 | 26篇 |
1974年 | 31篇 |
1973年 | 38篇 |
1971年 | 27篇 |
排序方式: 共有6591条查询结果,搜索用时 671 毫秒
121.
122.
Melissa Slavin Eliza Barach Stacey Farmer Rachel Luba Mitch Earleywine 《Addiction Research & Theory》2017,25(5):383-389
Cannabis has been found to alleviate a wide array of medical symptoms, including those that overlap with physical and emotional symptoms of premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD), including insomnia, irritability, depression, and joint pain. Little work has addressed the use of cannabis as a treatment for PMS or PMDD or the role of women’s cannabis treatment expectancies as a predictor of consumption. Women who reported having experienced PMS and PMDD and endorsed lifetime cannabis use (N?=?145), completed an online survey assessing their frequency of cannabis use, PMS/PMDD symptoms, expectancies of cannabis-induced relief from symptoms, as well as cannabis-related problems. Women were found to hold meaningful expectancies that cannabis would treat all PMS/PMDD symptoms, except for overeating/food cravings. Cannabis treatment expectancies were positively associated with PMS/PMDD symptoms and with monthly cannabis use, and were negatively associated with cannabis-related problems. Research should further examine the relationship of cannabis treatment expectancies with individuals’ cannabis use, as findings indicate the potential for these expectancies to serve a punitive or protective role in the development of cannabis-related problems. Increased research on how cannabis might ameliorate symptoms of PMS and PMDD could help establish an alternative treatment plan that offers relief with fewer negative side effects. 相似文献
123.
124.
125.
Kristine Krajnak G. R. Miller Stacey Waugh 《Journal of toxicology and environmental health. Part A》2018,81(1-3):6-19
Repetitive exposure to hand-transmitted vibration is associated with development of peripheral vascular and sensorineural dysfunctions. These disorders and symptoms associated with it are referred to as hand-arm vibration syndrome (HAVS). Although the symptoms of the disorder have been well characterized, the etiology and contribution of various exposure factors to development of the dysfunctions are not well understood. Previous studies performed using a rat-tail model of vibration demonstrated that vascular and peripheral nervous system adverse effects of vibration are frequency-dependent, with vibration frequencies at or near the resonant frequency producing the most severe injury. However, in these investigations, the amplitude of the exposed tissue was greater than amplitude typically noted in human fingers. To determine how contact with vibrating source and amplitude of the biodynamic response of the tissue affects the risk of injury occurring, this study compared the influence of frequency using different levels of restraint to assess how maintaining contact of the tail with vibrating source affects the transmission of vibration. Data demonstrated that for the most part, increasing the contact of the tail with the platform by restraining it with additional straps resulted in an enhancement in transmission of vibration signal and elevation in factors associated with vascular and peripheral nerve injury. In addition, there were also frequency-dependent effects, with exposure at 250 Hz generating greater effects than vibration at 62.5 Hz. These observations are consistent with studies in humans demonstrating that greater contact and exposure to frequencies near the resonant frequency pose the highest risk for generating peripheral vascular and sensorineural dysfunction. 相似文献
126.
Janna M. Schurer Momar Ndao Helen Quewezance Stacey A. Elmore Emily J. Jenkins 《The American journal of tropical medicine and hygiene》2014,90(6):1184-1190
Residents of remote and Indigenous communities might experience higher exposure to some zoonotic parasites than the general North American population. Human sero-surveillance conducted in two Saulteaux communities found 113 volunteers exposed as follows: Trichinella (2.7%), Toxocara canis (4.4%), Echinococcus (4.4%), and Toxoplasma gondii (1.8%). In dogs, 41% of 51 fecal samples were positive for at least one intestinal parasite, 3% of 77 were sero-positive for Borrelia burgdorferi, and 21% of 78 for T. gondii. Echinococcus exposure was more likely to occur in non-dog owners (odds ratio [OR]: 11.4, 95% confidence interval [CI]: 1.2–107, P = 0.03); while T. canis was more likely to occur in children (ages 4–17) (OR: 49, 95% CI: 3.9–624; P = 0.003), and those with a history of dog bites (OR: 13.5, 95% CI: 1.02–179; P = 0.048). Our results emphasize the use of dogs as sentinels for emerging pathogens such as Lyme disease, and the need for targeted surveillance and intervention programs tailored for parasite species, cultural groups, and communities. 相似文献
127.
Erik A. Karlsson Gregory A. Engel M.M. Feeroz Sorn San Aida Rompis Benjamin P. Y.-H. Lee Eric Shaw Gunwha Oh Michael A. Schillaci Richard Grant John Heidrich Stacey Schultz-Cherry Lisa Jones-Engel 《Emerging infectious diseases》2012,18(10):1672-1675
To determine whether nonhuman primates are infected with influenza viruses in nature, we conducted serologic and swab studies among macaques from several parts of the world. Our detection of influenza virus and antibodies to influenza virus raises questions about the role of nonhuman primates in the ecology of influenza. 相似文献
128.
129.
130.
Breton M Farret A Bruttomesso D Anderson S Magni L Patek S Dalla Man C Place J Demartini S Del Favero S Toffanin C Hughes-Karvetski C Dassau E Zisser H Doyle FJ De Nicolao G Avogaro A Cobelli C Renard E Kovatchev B;on behalf of The International Artificial Pancreas 《Diabetes》2012,61(9):2230-2237
Integrated closed-loop control (CLC), combining continuous glucose monitoring (CGM) with insulin pump (continuous subcutaneous insulin infusion [CSII]), known as artificial pancreas, can help optimize glycemic control in diabetes. We present a fundamental modular concept for CLC design, illustrated by clinical studies involving 11 adolescents and 27 adults at the Universities of Virginia, Padova, and Montpellier. We tested two modular CLC constructs: standard control to range (sCTR), designed to augment pump plus CGM by preventing extreme glucose excursions; and enhanced control to range (eCTR), designed to truly optimize control within near normoglycemia of 3.9-10 mmol/L. The CLC system was fully integrated using automated data transfer CGM→algorithm→CSII. All studies used randomized crossover design comparing CSII versus CLC during identical 22-h hospitalizations including meals, overnight rest, and 30-min exercise. sCTR increased significantly the time in near normoglycemia from 61 to 74%, simultaneously reducing hypoglycemia 2.7-fold. eCTR improved mean blood glucose from 7.73 to 6.68 mmol/L without increasing hypoglycemia, achieved 97% in near normoglycemia and 77% in tight glycemic control, and reduced variability overnight. In conclusion, sCTR and eCTR represent sequential steps toward automated CLC, preventing extremes (sCTR) and further optimizing control (eCTR). This approach inspires compelling new concepts: modular assembly, sequential deployment, testing, and clinical acceptance of custom-built CLC systems tailored to individual patient needs. 相似文献