全文获取类型
收费全文 | 460篇 |
免费 | 26篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 11篇 |
妇产科学 | 11篇 |
基础医学 | 35篇 |
口腔科学 | 4篇 |
临床医学 | 23篇 |
内科学 | 160篇 |
皮肤病学 | 8篇 |
神经病学 | 24篇 |
特种医学 | 4篇 |
外科学 | 71篇 |
综合类 | 19篇 |
预防医学 | 35篇 |
眼科学 | 10篇 |
药学 | 38篇 |
肿瘤学 | 35篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 11篇 |
2021年 | 23篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 16篇 |
2017年 | 12篇 |
2016年 | 25篇 |
2015年 | 15篇 |
2014年 | 29篇 |
2013年 | 38篇 |
2012年 | 44篇 |
2011年 | 51篇 |
2010年 | 20篇 |
2009年 | 16篇 |
2008年 | 26篇 |
2007年 | 31篇 |
2006年 | 28篇 |
2005年 | 35篇 |
2004年 | 23篇 |
2003年 | 13篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
排序方式: 共有490条查询结果,搜索用时 15 毫秒
1.
Neuropsychiatric symptoms are common in older adults with dementia and can be associated with a rapid decline in cognitive and functional status. This article reviews the current literature supporting the use of atypical antipsychotic medications in this population. Among the currently available atypical antipsychotics, risperidone and olanzapine have been the most widely studied in double-blind, randomized, placebo-controlled clinical trials. Despite the common use of other atypical antipsychotic medications, their efficacy and safety in older adults with dementia has not been as extensively studied. Some controversy surrounds the use of atypical antipsychotic agents in older adults with the suggestion that they may increase the incidence of stroke or even death. Despite the potential for increased risk of harm from the use of these medications, atypical antipsychotics are often effective in treating troublesome neuropsychiatric symptoms refractory to other treatments. Whenever possible, these atypical antipsychotic drug treatments should be combined with non-pharmacological treatments to limit the need and dose of antipsychotic drugs and constant monitoring for potential harms should be maintained. The choice of which atypical antipsychotic agent can be guided by the nature and severity of the target symptom and the medication least likely to cause harm to the patient. 相似文献
2.
3.
Stroke-prone rat strains exhibit an increased stroke risk and sensitivity, and reduced endogenous mechanisms of ischemic brain tolerance. This experiment provides a comparative, serial evaluation of neurological deficits and brain injury following middle cerebral artery occlusion/permanent focal stroke in this high-risk strain. Stroke-prone spontaneously hypertensive (SHR-SP), spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats were evaluated over 28 days using magnetic resonance imaging (MRI), histopathology, and neurobehavioral testing. T2- and diffusion weighted-MRI was performed after 1, 10 and 28 days to measure the degree of stroke-induced brain injury. Normotensive WKY rats receiving the same stroke and other SHR-SP rats receiving sham surgery were used for control comparisons. Functional deficits were scored after 1, 4, 11, 18 and 28 days. The degree of brain infarction/injury was practically identical in hypertensive and stroke-prone rats. WKY rats exhibited significantly smaller infarcts (P<0.05), with neurological function recovering quickly to normal by day 11 in this strain. Functional deficits persisted longer in hypertensive rats, with function recovering to normal by day 18 (P<0.05). Functional deficits in SHR-SP rats persisted the longest, and were observed even after 28 days (P<0.05). This increased and prolonged neurologic dysfunction exhibited by SHR-SP compared to SHR rats, while exhibiting practically identical degrees of brain injury/infarction, reflects the increased stroke risk and sensitivity of this strain and suggests a reduced SHR-SP brain plasticity following injury. Therefore, the stroke-prone rat provides an enhanced and prolonged functional deficit model that can be used to elucidate those mechanisms/novel targets critical to longitudinal neurobehavioral recovery post-stroke. 相似文献
4.
5.
6.
7.
Among the digenetic trematodes, paramphistomes are known to be the causative agent of “amphistomiasis” or the stomach fluke disease of domestic and wild animals, mainly ruminants. The use of 28S (divergent domains) and 18S rRNA for phylogenetic inference is significantly warranted for these flukes since it is as yet limited to merely the exploration of the second internal transcribed spacer (ITS2) region. The present study intended to explore the divergent domains (D1–D3) of 28S rRNA and simultaneously equate the phylogenetic information with 18S rRNA in paramphistomes. Divergence of the 28S rRNA domains was evident amongst the divergent (D) domains, where D1 domain emerged as the most variable and D2, the most robust domain, since the latter could provide a higher resolution of the species. D2 was the only domain that comprised compensatory mutations in the helices of its structural constraints; this domain is thus well suited for species distinction and may be considered a potential DNA barcode complementary to mitochondrial DNA. 28S (D1?+?D2?+?D3) rRNA provided a significant resolution of the taxa corroborating with the taxonomy of these flukes and thus proved to be more robust as a phylogenetic marker for lower levels than 18S rRNA. Phylogenetic inferences of paramphitomes are still scarcely explored; additional data from other taxa belonging to this family may estimate better the biodiversity of these flukes. 相似文献
8.
Priyadarshan Anand Jategaonkar Smita Priyadarshan Jategaonkar Sudeep Pradeep Yadav 《Hellēnikē cheirourgikē. Acta chirurgica Hellenica》2016,88(1):52-54
Nowadays, laparoscopic cholecystectomy for gallstone disease is considered not only the gold standard but an essential component of surgical training. In this regard, liver retraction plays an important role during cholecystectomy and also after specimen extraction. We describe a simple technique for liver retraction that achieves rapid, safe and steady exposure of the cystic fossa along with the subhepatic region for tackling any inadvertent bile leaks or bleeding. It is especially useful for diseased livers which are otherwise prone to iatrogenic laceration during haphazard and uncontrolled hepatic manipulation. Nonetheless, it may be easily mastered by surgical trainees, and thus reduce their learning curve. 相似文献
9.
Rathor Laxmi Pant Aakanksha Nagar Abhishek Tandon Sudeep Trivedi Shalini Pandey Rakesh 《Proceedings of the National Academy of Sciences, India. Section B.》2017,87(4):1355-1362
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The use of herbs in the form of dietary supplements and medicine is fascinating the world, owing to their... 相似文献
10.
Use of angiotensin-converting enzyme inhibitor therapy and dose-related outcomes in older adults with new heart failure in the community
下载免费PDF全文
![点击此处可从《Journal of general internal medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Rochon PA Sykora K Bronskill SE Mamdani M Anderson GM Gurwitz JH Gill S Tu JV Laupacis A 《Journal of general internal medicine》2004,19(6):676-683
OBJECTIVE: To evaluate the dose-related benefit of angiotensin-converting enzyme (ACE) inhibitor therapy among older adults with heart failure and to evaluate whether low-dose ACE inhibitor therapy is better than none. DESIGN: Observational cohort study. SETTING: Community-dwelling older adults in Ontario, Canada. PATIENTS/PARTICIPANTS: We identified 16539 adults 66 years or older who survived 45 days following their first heart failure hospitalization discharge. MEASUREMENT AND MAIN RESULTS: Multivariate techniques including propensity scores were used to study the association between the dose of ACE inhibitor therapy dispensed and 3 outcomes: survival, survival or heart failure rehospitalization, and survival or all-cause hospitalization at 1 year of follow-up. Logistic regression models explored the association between initial dose dispensed and subsequent dose reduction or drug cessation. Overall, 10793 (65.3%) of patients were dispensed ACE inhibitor therapy, with more than a third (3935; 36.5%) initiated on low-dose therapy. Relative to dispensing of low-dose ACE inhibitor therapy, nonuse was associated with increased mortality (hazard ratio [HR], 1.12; 95% confidence interval [CI], 1.02 to 1.22). Dispensing medium-dose therapy provided a benefit similar to low-dose (HR, 0.94; CI, 0.86 to 1.03) and dispensing of high-dose therapy was associated with improved survival benefit (HR, 0.76; CI, 0.68 to 0.85). Relative to dispensing of low-dose ACE inhibitor therapy, dispensing high-dose conferred a benefit (HR, 0.87; CI, 0.80 to 0.95) on the composite outcome of 1-year mortality or heart failure hospitalization and the composite outcome of 1-year mortality or all-cause hospitalization (HR, 0.87; CI, 0.81 to 0.93). Relative to those dispensed low-dose ACE inhibitor therapy, those initially dispensed high-dose therapy were twice as likely to have their subsequent dose reduced or the therapy discontinued (odds ratio, 2.36; CI, 2.07 to 2.69). CONCLUSION: Our findings suggest that when possible, older adults should be titrated to the higher doses of ACE inhibitor therapy evaluated in clinical trials. If older adults cannot tolerate higher doses, then low-dose ACE inhibitor therapy is superior to none. High-dose ACE inhibitor therapy is not as well tolerated as lower doses. 相似文献