首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   412篇
  免费   31篇
耳鼻咽喉   3篇
儿科学   11篇
妇产科学   11篇
基础医学   46篇
临床医学   32篇
内科学   54篇
皮肤病学   14篇
神经病学   101篇
特种医学   3篇
外科学   52篇
综合类   4篇
预防医学   35篇
眼科学   12篇
药学   36篇
中国医学   1篇
肿瘤学   28篇
  2024年   1篇
  2023年   10篇
  2022年   17篇
  2021年   31篇
  2020年   9篇
  2019年   32篇
  2018年   30篇
  2017年   16篇
  2016年   12篇
  2015年   11篇
  2014年   15篇
  2013年   24篇
  2012年   36篇
  2011年   27篇
  2010年   17篇
  2009年   13篇
  2008年   24篇
  2007年   15篇
  2006年   16篇
  2005年   19篇
  2004年   13篇
  2003年   11篇
  2002年   14篇
  2001年   3篇
  2000年   2篇
  1999年   4篇
  1998年   3篇
  1997年   2篇
  1996年   2篇
  1995年   2篇
  1994年   2篇
  1992年   2篇
  1991年   1篇
  1989年   1篇
  1988年   1篇
  1981年   1篇
  1935年   2篇
  1934年   2篇
排序方式: 共有443条查询结果,搜索用时 15 毫秒
51.
Objective: We conducted a randomized controlled trial of the Aging Well through Interaction and Scientific Education (AgeWISE) program, a 12-week manualized cognitive rehabilitation program designed to provide psychoeducation to older adults about the aging brain, lifestyle factors associated with successful brain aging, and strategies to compensate for age related cognitive decline.

Methods: Forty-nine cognitively intact participants ≥ 60 years old were randomly assigned to the AgeWISE program (n = 25) or a no-treatment control group (n = 24). Questionnaire data were collected prior to group assignment and post intervention. Two-factor repeated-measures analyses of covariance (ANCOVAs) were used to compare group outcomes.

Results: Upon completion, participants in the AgeWISE program reported increases in memory contentment and their sense of control in improving memory; no significant changes were observed in the control group. Surprisingly, participation in the group was not associated with significant changes in knowledge of memory aging, perception of memory ability, or greater use of strategies.

Conclusions: The AgeWISE program was successfully implemented and increased participants’ memory contentment and their sense of control in improving memory in advancing age.

Clinical Implications: This study supports the use of AgeWISE to improve perspectives on healthy cognitive aging.  相似文献   

52.
53.
54.
Summary: Purpose: The influence of sleep on the incidence of seizures and the reciprocal effects of epilepsy on sleep were analyzed in 30 patients with intractable partial seizures, all candidates for surgery.
Methods: The patients were classified into two groups of 15 patients according to the documented site of the epileptogenic zone: frontal lobe epilepsy (FLE) and medial temporal lobe epilepsy (TLE). Frequency and waking-sleep distribution of seizures were evaluated by continuous video-EEG monitoring for 5 days, under defined antiepileptic drug (AED), sleep, and sleep deprivation regimens. Sleep organization was analyzed by polysomnography prior to the presurgical protocol.
Results: Significant differences were found between the two groups in sleeping-waking distribution of seizures under varied conditions, and in the quality of sleep organization. In FLE patients, seizures most often occurred during sleep, although sleep organization was normal. In TLE patients, most seizures occurred while patients were awake, and sleep organization was characterized by a low efficiency index. The difference in seizure distribution between FLE and TLE persisted under all conditions investigated, i.e., after AED discontinuation and sleep deprivation.
Conclusions: Sleep recording may be useful for diagnosis of FLE, and monitoring after sleep deprivation for that of TLE. We speculate that sleep-related seizures in FLE may depend on interaction between frontal lobe areas with the thalamus cortical synchronization system and the acetylcholine regulatory system of waking.  相似文献   
55.
56.
Photodynamic therapy (PDT) has significant promise in improving outcomes of patients with a variety of cutaneous conditions. A group of experts met to review the principles, indications, and clinical benefits of PDT with 5-aminolevulinic acid (ALA). They also reviewed PDT with methyl aminolevulinate. The experts established consensus statements for pretreatment, posttreatment, ALA contact time, light sources, and numbers of sessions associated with ALA PDT for actinic keratosis and superficial basal cell carcinoma, photorejuvenation and cosmetic enhancement, acne, sebaceous skin, rosacea, and rhinophyma. They based consensus recommendations on their clinical experience and the medical literature. They also suggested future applications of ALA PDT. Experts concluded that ALA PDT is a safe and effective modality for the treatment of conditions commonly encountered in dermatology. Since downtime is minimal, the technique is suitable for patients of all ages and lifestyles. Appropriate light sources are available in many dermatology offices. The expanding clinical and financial benefits of PDT justify the purchase of an appropriate light source.  相似文献   
57.
Methamphetamine use among young adults: health and social consequences   总被引:2,自引:0,他引:2  
The current research analyzed the relationship between methamphetamine use and health and social outcomes. Interviews were conducted with a sample of 106 respondents. Virtually all of the respondents experienced negative consequences of methamphetamine use. The most serious, but least prevalent, methamphetamine-related health problem was seizures and convulsions. The most prevalent health effect was weight lose. A substantial number of respondents experienced severe psychological symptoms: depression, hallucinations, and paranoia. Of the 106 respondents, 34.9% had committed violence while under the influence of methamphetamine. The data suggest that methamphetamine-based violence was more likely to occur within private domestic contexts, both family and acquaintance relationships. It is apparent from the findings that methamphetamine use heightens the risk for negative health, psychological, and social outcomes. Having said this, it is crucial to acknowledge that there was no evidence of a single, uniform career path that all chronic methamphetamine users follow. Furthermore, a significant number of sample members experienced limited or no serious social, psychological, or physical dysfunction as a result of their methamphetamine use.  相似文献   
58.
BACKGROUND: We sought to determine the extent to which the age-related decline of femoral neck (FN) bone mineral density (BMD) might be explained by the age-related change of body composition and biological parameters and the mechanisms by which these factors might influence FN BMD in men. METHODS: The relationships between FN BMD and anthropometric, hormonal, and biochemical parameters and bone turnover markers were studied in 82 men aged 25-86 years. RESULTS: Age was associated with a decline of FN BMD and osteocalcin (OC), bone alkaline phosphatase (bALP), and urinary C-telopeptide (p <.05). The significant relationship between FN BMD and OC (p <.01) did not remain after adjustment for age. With use of multiple linear regression and adjusting for all significant variables associated with FN BMD in univariate analysis (p <.01) (age, weight, lean and fat mass, height, and levels of dehydroepiandrosterone sulfate, insulin-like growth factor [IGF-1], testosterone, and parathyroid hormone [PTH]), age accounted for 29.5% of FN BMD variance. When age was excluded from the model, PTH accounted for 19.5% and IGF-1 for 10% of the FN BMD variance. Bone turnover markers were significantly intercorrelated, and levels of IGF-1 were positively associated with those of bALP and OC (p <.05). CONCLUSIONS: These results show that age is a strong predictor of FN BMD in men, resulting in a decline of bone remodeling, especially of bone formation. The results also show that, after taking into account anthropometric and other biological factors possibly involved in bone aging, the major part of the effect of age on bone is explained by the age-related increase of PTH and decrease of IGF-1 in men, suggesting that all measures taken to limit these age-related changes may be effective in the prevention of the age-related decline of FN BMD in men.  相似文献   
59.
The effect of ophthalmectomy (enucleation) on plasma melatonin in Rana tadpoles and froglets was studied under various experimental conditions to determine if ocular melatonin is released into the circulation from the eyes and to study the factors which might affect this process. Where operations occurred in early or mid-photophase on a 12 light:12 dark (12L:12D) cycle (light onset at 08:00 h), sampling in mid-light and mid-dark revealed that scotophase plasma melatonin was reduced at all developmental stages, with the more significant effects occurring before metamorphic climax. Experiments sampling prometamorphic tadpoles six times in a 24h period on 18L:6D, 12L:12D, or 6L:18D five days after enucleation also showed a significant lowering of plasma melatonin in the dark, so that the scotophase peak was virtually eliminated on all the LD cycles. These findings indicated that the reduction in plasma melatonin after bilateral eye removal was independent of the LD cycle and the metamorphic stage, and that it abolished the diel melatonin rhythm at the expense of the scotophase peak. Experiments carried out for 5 weeks suggested that compensatory secretion of melatonin by other organs after eye removal might partially restore the plasma melatonin level over time. Unilateral ophthalmectomy tended to reduce, but not eliminate, the night peak of plasma melatonin, and did not result in a compensatory increase in ocular melatonin in the remaining eye. Ophthalmectomized tadpoles exhibited darkening of the skin after the operation, which was not associated with a significant change in pituitary alpha-melanotropin. The findings overall indicate that the eyes in Rana tadpoles and froglets contribute up to somewhat over one-half of the circulating melatonin, particularly during the scotophase, and provide experimental evidence for ocular secretion into the blood for the first time in the Amphibia.  相似文献   
60.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号