全文获取类型
收费全文 | 13628篇 |
免费 | 966篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 97篇 |
儿科学 | 429篇 |
妇产科学 | 383篇 |
基础医学 | 1601篇 |
口腔科学 | 235篇 |
临床医学 | 2307篇 |
内科学 | 2104篇 |
皮肤病学 | 235篇 |
神经病学 | 1256篇 |
特种医学 | 435篇 |
外科学 | 1398篇 |
综合类 | 272篇 |
一般理论 | 25篇 |
预防医学 | 1593篇 |
眼科学 | 299篇 |
药学 | 883篇 |
2篇 | |
中国医学 | 7篇 |
肿瘤学 | 1056篇 |
出版年
2023年 | 56篇 |
2022年 | 47篇 |
2021年 | 222篇 |
2020年 | 153篇 |
2019年 | 254篇 |
2018年 | 299篇 |
2017年 | 231篇 |
2016年 | 222篇 |
2015年 | 262篇 |
2014年 | 347篇 |
2013年 | 612篇 |
2012年 | 847篇 |
2011年 | 984篇 |
2010年 | 524篇 |
2009年 | 498篇 |
2008年 | 870篇 |
2007年 | 870篇 |
2006年 | 948篇 |
2005年 | 917篇 |
2004年 | 960篇 |
2003年 | 886篇 |
2002年 | 800篇 |
2001年 | 223篇 |
2000年 | 152篇 |
1999年 | 148篇 |
1998年 | 153篇 |
1997年 | 109篇 |
1996年 | 78篇 |
1995年 | 108篇 |
1994年 | 82篇 |
1993年 | 87篇 |
1992年 | 132篇 |
1991年 | 93篇 |
1990年 | 106篇 |
1989年 | 90篇 |
1988年 | 74篇 |
1987年 | 79篇 |
1986年 | 101篇 |
1985年 | 75篇 |
1984年 | 77篇 |
1983年 | 82篇 |
1982年 | 70篇 |
1981年 | 71篇 |
1980年 | 74篇 |
1979年 | 50篇 |
1978年 | 53篇 |
1977年 | 44篇 |
1976年 | 40篇 |
1973年 | 38篇 |
1970年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
991.
992.
Effects of rapid tryptophan depletion on sleep electroencephalogram and mood in subjects with partially remitted depression on bupropion. 总被引:3,自引:0,他引:3
Lynn Evans Shahrokh Golshan John Kelsoe Mark Rapaport Kathryn Resovsky Laura Sutton J Christian Gillin 《Neuropsychopharmacology》2002,27(6):1016-1026
Serotonin has been implicated in both sleep and mood regulation. When central serotonin was depleted with a tryptophan-free amino acid drink (TFD), some studies have reported that the antidepressant benefits were reversed in partially remitted patients treated with SSRIs. Other studies showed that the TFD increased rapid eye movement (REM) sleep in both normal males and in remitted depression patients on selective serotonin reuptake inhibitors (SSRIs) without affecting mood. In this study, we administered a TFD to patients with remitted depression who were being treated with bupropion, an antidepressant whose mechanism of action apparently does not affect the serotonin system. We hypothesized that the TFD would increase the propensity for REM sleep without affecting depression ratings. Eight partially remitted depression subjects on bupropion were administered a TFD and a control drink containing tryptophan in double-blind, random order on separate days. The effects of these drinks were monitored with sleep electroencephalograms, mood ratings, and plasma tryptophan measures comparing baseline, TFD, and control nights. The TFDs reduced REM latency and stage 2 percent and increased REM time and percent. Subjective measures of elation, vigor, and friendliness significantly decreased on both TFD and control drinks but depression ratings did not. Plasma levels of tryptophan decreased with the TFD. Although the TFD altered REM sleep, certain mood measures, and plasma tryptophan levels, no relapses into depression were seen with our subjects. Bupropion alone did not affect sleep measures. 相似文献
993.
994.
995.
Tracy L. Veach Richard H. Rahe Robbyn L. Tolles Lynn M. Newhall 《Stress and health》2003,19(5):257-264
This study investigates the efficacy of an intensive, integrated approach to stress reduction and coping enhancement directed towards an educated, upper level management population. Ninety‐five US governmental senior managers participated in a 35‐h stress management retreat held over a 3.5‐day period. The retreat combined didactic and experiential activities that were designed to increase participants' knowledge of stress liabilities and coping skills. Participants were encouraged to make positive lifestyle changes and to create specific action plans for the year following the workshop. Evaluations of participant satisfaction were completed at the close of the workshop. Eighty‐three participants completed baseline and follow‐up Stress and Coping Inventory (SCI) assessments in order to identify durable changes in these measures. Across 10 months, participants showed significant improvements in their overall Global Balance scores, psychological symptoms, depression symptoms, and all major coping scales, including Health Habits, Social Support, Responses to Stress and Life Satisfactions. Therefore, an intensive, multifaceted approach to stress intervention is a viable option for encouraging sustained behavioural change. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
996.
Ganapathy A Prasad Kenneth K Wang Lori S Lutzke Jason T Lewis Schuyler O Sanderson Navtej S Buttar Louis M Wong Kee Song Lynn S Borkenhagen Lawrence J Burgart 《Clinical gastroenterology and hepatology》2006,4(2):173-178
BACKGROUND & AIMS: The aim of this study was to assess the validity of frozen section analysis of endoscopic mucosal resection (EMR) specimens from Barrett's esophagus as compared with permanent sections for the detection of neoplasia. Frozen sections help to give immediate feedback for surgical procedures. It has not been determined whether EMR can be adequately interpreted by using frozen sections to aid endoscopists in completely resecting neoplastic lesions. METHODS: EMR specimens from Barrett's esophagus with high-grade dysplasia (HGD) and/or carcinoma were tested by frozen section. Pathologists evaluated EMR specimens for the depth of invasion as well as the appearance of clear margins of resection. The kappa statistic was calculated to assess the degree of agreement between the frozen section and permanent section diagnoses. RESULTS: Twenty-three consecutive patients underwent 30 EMRs with frozen section diagnosis. Frozen section revealed a carcinoma in 7 specimens (23%) and dysplasia in 20 (66%). Permanent sections found carcinoma in 8 specimens (26%), dysplasia in 19 specimens (63%), and normal or nondysplastic Barrett's esophagus in the remainder. The kappa statistic for the depth of invasion of EMR specimens was 0.93 (near perfect agreement). The kappa statistic for the margins of the EMR specimens was 0.80 (excellent agreement). CONCLUSIONS: This study indicated that frozen section analysis of esophageal EMR specimens is valid as compared with permanent section. This technique might allow rapid evaluation about the degree and depth of involvement of cancers. This allows physicians to make decisions regarding further therapy if margins are involved or decrease the use of EMR for histologically benign-appearing lesions. 相似文献
997.
Lynn Marie Trotti David B Rye Donald L Bliwise 《Movement disorders》2007,22(10):1520; author reply 1520-1520; author reply 1521
998.
Terry Lynn Gall 《Quality of life research》2004,13(8):1357-1368
This study explored the role of relationship with God with respect to the quality of life of men with prostate cancer. Thirty-four men with prostate cancer completed questionnaires on demographic and illness factors, aspects of relationship with God (e.g., God image), nonreligious resources (e.g., optimism) and physical, social and emotion functioning. Results showed that relationship with God was a significant factor in the prediction of role, emotional and social functioning for these men after controlling for age, reported severity of treatment reactions and nonreligious resources. Notably, different aspects of relationship with God (e.g., causal attribution) evidenced different associations with functioning and the nonreligious resource of perceived health control. Such results suggest that relationship with God may function in a complex manner as a resource in coping with prostate cancer. Longitudinal research is needed to clarify the role of religious/spiritual resources in the short- and long-term quality of life of men with prostate cancer. 相似文献
999.
S. Y. Wong E. M. Lau W. W. Lau† & H. S. Lynn 《Journal of human nutrition and dietetics》2004,17(4):359-364
To determine the feasibility of increasing the calcium, protein and calorie intake of osteoporotic fracture patients by repeated dietary counselling delivered by a dietitian, a randomized controlled trial was conducted. Among 189 patients presenting with osteoporotic fractures to an Orthopaedics and Traumatology Department of a large regional hospital, 98 patients were randomized to the intervention group and 91 were randomized to the control group (with usual care). Intervention group received three sessions of dietary counselling with tailored made recommendations over a period of 4 months, while the control group only received dietary assessment and pamphlets on the prevention of osteoporosis. Almost all subjects in both intervention and control groups had calcium intake below the recommended level of 1000 mg at baseline. Half and 60% of subjects in both groups had total energy and protein intake below recommended levels respectively. The mean weights of control and intervention groups at baseline were 51.5 and 50.9 kg respectively, while the body mass index (BMI) were 22.6 (kg m(-2)) and 22.6 (kg m(-2)) respectively. After dietary intervention, significant increase of intake was seen in calcium intake (P = 0.0095 by t-test) in the intervention group. No significant increase was seen in protein or calorie intake. No significant change was observed in the body weight or BMI although there was a positive trend in the intervention group for all these parameters. We concluded that there was general malnutrition in Chinese elderly who presented with osteoporotic fractures. Dietary calcium could be increased by repeated professional dietary counselling. Future studies with longer duration and more objective clinical outcomes will be helpful to further demonstrate the long-term effects of dietary intervention on osteoporosis and other chronic diseases. 相似文献
1000.
Tanya M. Spruill Thomas G. Pickering Joseph E. Schwartz Elizabeth Mostofsky Gbenga Ogedegbe Lynn Clemow William Gerin 《Annals of behavioral medicine》2007,34(1):1-9
Background: The white coat effect can lead to overdiagnosis of hypertension and unnecessary pharmacologic treatment. Mechanisms underlying
the white coat effect remain poorly understood but are critical to improving the accuracy of clinic blood pressure measurement.Purpose: This study investigated whether perceived hypertension status was associated with state anxiety levels during a clinic visit
and the magnitude of the white coat effect, independent of true blood pressure status.Methods: This observational study included 214 normotensive and mildly hypertensive participants who were 18 to 80 years old, had
no cardiac history, and were willing to discontinue antihypertensive medications for 8 weeks. Participants underwent 36 hr
ambulatory blood pressure monitoring and physician blood pressure measurement. Outcome measures were state anxiety reported
during the clinic visit and the white coat effect.Results: An analysis of covariance indicated that participants who perceived themselves as hypertensive reported greater state anxiety
(p<.001) and showed larger white coat effects (ps<.01) compared with those who perceived themselves as normotensive. True
hypertension status based on ambulatory blood pressure was not related to either outcome. Anxiety accounted for approximately
19% of the association between perceived hypertension status and the white coat effect.Conclusions: These findings suggest that the perception of being hypertensive is associated with greater anxiety during clinic blood pressure
measurement and a larger white coat effect, independent of the true blood pressure level. Anxiety appears to be a mechanism
by which perceived hypertension status contributes to the white coat effect.
Preparation of this article was supported in part by the National Heart, Lung, and Blood Institute, National Institutes of
Health, Grants HL47540 and HL76857, T. G. Pickering, Principal Investigator. The sponsors had no role in the study design;
in the collection, analysis, or interpretation of the data; in the writing of this article; or in the decision to submit the
article for publication. 相似文献