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   562篇
  免费   77篇
  国内免费   5篇
耳鼻咽喉   2篇
儿科学   67篇
妇产科学   12篇
基础医学   101篇
口腔科学   30篇
临床医学   58篇
内科学   111篇
皮肤病学   5篇
神经病学   30篇
特种医学   67篇
外科学   46篇
综合类   34篇
预防医学   43篇
眼科学   1篇
药学   14篇
中国医学   4篇
肿瘤学   19篇
  2021年   10篇
  2020年   8篇
  2019年   8篇
  2018年   7篇
  2017年   9篇
  2016年   8篇
  2015年   20篇
  2014年   10篇
  2013年   19篇
  2012年   22篇
  2011年   24篇
  2010年   30篇
  2009年   17篇
  2008年   22篇
  2007年   13篇
  2006年   16篇
  2005年   21篇
  2004年   11篇
  2003年   15篇
  2002年   10篇
  2001年   9篇
  2000年   15篇
  1999年   10篇
  1998年   24篇
  1997年   16篇
  1996年   20篇
  1995年   9篇
  1994年   14篇
  1993年   11篇
  1992年   9篇
  1991年   16篇
  1990年   15篇
  1989年   22篇
  1988年   20篇
  1987年   18篇
  1986年   16篇
  1985年   14篇
  1984年   9篇
  1983年   8篇
  1982年   10篇
  1981年   3篇
  1980年   7篇
  1979年   7篇
  1978年   4篇
  1977年   8篇
  1976年   10篇
  1975年   4篇
  1974年   3篇
  1971年   2篇
  1881年   5篇
排序方式: 共有644条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
Background/aimThe known pathogenesis of diabetes mellitus (DM) in acromegaly is mainly based on growth hormone (GH) and insulin-like growth factor-1 (IGF-1) excess. Fatty acid-binding protein 4 (FABP-4), a novel adipokine, is found to induce insulin resistance and type 2 DM. We aimed to investigate the possible effect of FABP-4 on glucose metabolism in patients with acromegaly.Materials and methodsThis case-control study included 28 patients newly diagnosed with acromegaly and 57 healthy volunteers. The patients with acromegaly were classified according to their glycemic status as with DM, prediabetes, and normal glucose tolerance. Anthropometric measurements, laboratory test results, and FABP-4 levels of the subjects were evaluated.ResultsAlthough no difference was observed in FABP-4 levels between acromegaly and control groups, the FABP-4 level was higher in the patients with acromegaly having DM compared to the patients with acromegaly having prediabetes and NGT, and the control group (p = 0.004, p = 0.001, p = 0.004, respectively). Logistic regression analysis suggested that the FABP-4 is an independent predictor of DM in acromegaly (β = 7.382, OR = 38.96, 95% CI: 1.52-5.76, p = 0.018).Conclusion The FABP-4 may be a helpful predictor of acromegaly-associated DM.  相似文献   
105.
Cells within the trigeminal ganglion (Vg) encode all the information necessary for the rat to differentiate tactile stimuli, yet it is the least-studied component in the rodent trigeminal somatosensory system. For example, extensive anatomical and electrophysiological investigations have shown clear somatotopic organization in the higher levels of this system, including VPM thalamus and SI cortex, yet whether this conserved schemata exists in the Vg is unknown. Moreover although there is recent interest in recording from vibrissae-responsive cells in the Vg, it is surprising to note that the locations of these cells have not even been clearly demarcated. To address this, we recorded extracellularly from 350 sensory-responsive Vg neurons in 35 Long-Evans rats. First, we determined three-dimensional locations of these cells and found a finer detail of somatotopy than previously reported. Cells innervating dorsal facial features, even within the whisker region, were more dorsal than midline and ventral features. We also show more cells with caudal than rostral whisker receptive fields (RF), similar to that found in VPM and SI. Next, for each vibrissal cell we determined its response type classified as either rapidly (RA) or slowly (SA) adapting. We examined the relationship between vibrissal RF and response type and demonstrate similar proportions of RA and SA cells responding to any whisker. These results suggest that if RA and SA cells encode distinct features of stimuli, as previously suggested, then at the basic physiological level each whisker has similar abilities to encode for such features.  相似文献   
106.
107.
This systematic review examines critically the scientific basis for Canada's Physical Activity Guide for Healthy Active Living for adults. Particular reference is given to the dose-response relationship between physical activity and premature all-cause mortality and seven chronic diseases (cardiovascular disease, stroke, hypertension, colon cancer, breast cancer, type 2 diabetes (diabetes mellitus) and osteoporosis). The strength of the relationship between physical activity and specific health outcomes is evaluated critically. Literature was obtained through searching electronic databases (e.g., MEDLINE, EMBASE), cross-referencing, and through the authors' knowledge of the area. For inclusion in our systematic review articles must have at least 3 levels of physical activity and the concomitant risk for each chronic disease. The quality of included studies was appraised using a modified Downs and Black tool. Through this search we identified a total of 254 articles that met the eligibility criteria related to premature all-cause mortality (N = 70), cardiovascular disease (N = 49), stroke (N = 25), hypertension (N = 12), colon cancer (N = 33), breast cancer (N = 43), type 2 diabetes (N = 20), and osteoporosis (N = 2). Overall, the current literature supports clearly the dose-response relationship between physical activity and the seven chronic conditions identified. Moreover, higher levels of physical activity reduce the risk for premature all-cause mortality. The current Canadian guidelines appear to be appropriate to reduce the risk for the seven chronic conditions identified above and all-cause mortality.  相似文献   
108.
摘要:目的 探讨新疆乌鲁木齐市维吾尔族人群成人支气管哮喘的影响因素。方法 本研究采用成组匹配病例对照研究方法,病例组为新疆医科大学第一附属医院呼吸内科在2014年1-12月确诊的维吾尔族支气管哮喘成人患者(n=120例),对照组为同期体检中心健康维吾尔族体检者(n=126例),两组在年龄、性别相匹配。采用问卷调查的方法收集相关暴露资料,并采用单因素分析及多因素非条件Logistic回归模型分析成人支气管哮喘影响因素。结果 多因素Logistic回归分析显示,吸烟(OR=1.88,95% CI:1.28~2.96)、家族支气管哮喘史(OR=6.20,95% CI:2.10~18.31)、家中铺有纯毛地毯数量多(OR=1.87,95% CI:1.18~2.95),睡眠质量(OR=1.46,95% CI:1.22~1.75),患慢性支气管炎(OR=13.43,95% CI:6.65~25.34)及过敏性鼻炎(OR=6.27,95% CI:3.63~10.81)是维吾尔族成人支气管哮喘的主要影响因素。结论 维吾尔族成人支气管哮喘是生活方式、环境及遗传等多种因素共同作用的结果,应加强对相关影响因素的预防及治疗,减少哮喘的发生,改善哮喘患者生活质量。  相似文献   
109.
Loss of descending serotonergic (5-HT) projections after spinal cord injury (SCI) contributes to motor deficits and upregulation of receptors on partially denervated serotonergic targets in the spinal cord. Serotonergic agonists acting on these upregulated receptors are potential therapeutic agents that could ameliorate motor deficits. However, modification of 5-HT receptors following complete spinal cord injury results in different effects by 5-HT2C receptor agonists and antagonists. For example, administration of 5-HT2C receptor agonists suppresses locomotor activity in normal animals, but enhances it in spinalized animals. In addition, administration of 5-HT2C receptor agonists does not induce activity-dependent hindlimb tremors in normal animals, but does induce them in spinalized animals. We therefore extended our previous work with the 5-HT2C receptor agonist 1-(m-chlorophenyl)-piperazine hydrochloride (mCPP), which enhances weight-supported stepping when administered to adult rats spinalized as neonates, to identify the optimal dose for improved weight-supported stepping with minimal side effects. In order to determine whether mCPP enhances weight-supported stepping after SCI is through activation of the 5-HT2C receptor, we performed the following experiments. We determined that stimulation of the 5-HT1A receptor did not contribute to this improvement in weight-support. We reversed the increase in mCPP-induced weight-supported stepping with SB 206,553, a 5-HT2C receptor antagonist. We also provide evidence for denervation-induced upregulation of 5-HT2C receptors in the injured spinal cord. Since mCPP does not have the behavioral toxicity associated with non-selective 5-HT2 receptor agonists, targeting the 5-HT2C receptor may have clinical relevance for the treatment of SCI.  相似文献   
110.
Approximately 40% of older people in residential care have significant symptoms of depression. A training and care-planning approach to reducing depression was implemented for 114 depressed residents living in 14 residential care homes in North Yorkshire, UK. Care staff were offered brief mental health training by community mental health teams for older people. They were then assigned to work individually with residents in implementing the care-planning intervention, which was aimed at alleviating depression and any health, social or emotional factors that might contribute to the resident's depression. Clinically significant improvements in depression scores were associated with implementation of the care-planning intervention as evidenced by changes in scores on the Geriatric Mental State Schedule-Depression Scale. There was evidence of an interaction between the power of the intervention and degree of dementia. These improvements were not accounted for by any changes in psychotropic medication. The training was highly valued by care staff and heads of homes, and they considered that the care-planning intervention represented an improvement in quality of care for all residents, irrespective of levels of dementia. Staff also reported improvements in morale and increased confidence in the caring role as a result of their participation. The limitations of this study are discussed. On the basis of a growing body of evidence, it is argued that there is an urgent need for a suitably powered randomised controlled trial and economic evaluation, to test the cost-effectiveness of personalised care planning interventions aimed at reducing depression in older people in residential care.  相似文献   
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