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   600篇
  免费   48篇
  国内免费   3篇
耳鼻咽喉   6篇
儿科学   13篇
妇产科学   10篇
基础医学   62篇
口腔科学   14篇
临床医学   70篇
内科学   141篇
皮肤病学   17篇
神经病学   24篇
特种医学   11篇
外科学   126篇
综合类   12篇
一般理论   2篇
预防医学   25篇
眼科学   15篇
药学   36篇
肿瘤学   67篇
  2024年   2篇
  2023年   6篇
  2022年   16篇
  2021年   19篇
  2020年   13篇
  2019年   16篇
  2018年   30篇
  2017年   16篇
  2016年   20篇
  2015年   26篇
  2014年   27篇
  2013年   40篇
  2012年   49篇
  2011年   60篇
  2010年   34篇
  2009年   42篇
  2008年   42篇
  2007年   37篇
  2006年   33篇
  2005年   23篇
  2004年   24篇
  2003年   24篇
  2002年   25篇
  2001年   5篇
  2000年   2篇
  1999年   2篇
  1998年   1篇
  1997年   3篇
  1996年   2篇
  1994年   2篇
  1993年   2篇
  1992年   1篇
  1990年   1篇
  1989年   2篇
  1988年   1篇
  1987年   1篇
  1986年   1篇
  1981年   1篇
排序方式: 共有651条查询结果,搜索用时 15 毫秒
1.
Registered nurses working at a teaching hospital in Kuwait were surveyed to assess the psychosocial variables associated with their intention to comply with glove-wearing recommendations. Perceived consequences and normative beliefs, as well as sex and years of nursing experience, significantly influenced their behavioral intentions, suggesting that improvements in intention to comply are more likely to come from practical demonstrations that show nurses the potential outcomes of both using and not using gloves.  相似文献   
2.

Background

The current status of radioiodine-131 (RaI) dosimetry for Graves' hyperthyroidism is not clear. Recurrent hyperthyroidism and iatrogenic hypothyroidism are two problems which interact such that trying to solve one leads to exacerbation of the other. Optimized RaI therapy has therefore begun to be defined just in terms of early hypothyroidism (ablative therapy) as physicians have given up on reducing hypothyroidism.

Methods

Optimized therapy is evaluated both in terms of the greatest separation of cure rate from hypothyroidism rate (non-ablative therapy) or in terms of early hypothyroidism (ablative therapy) by mathematical modeling of outcome after radioiodine and critically discussing the three common methods of RaI dosing for Graves' disease.

Results

Cure follows a logarithmic relationship to activity administered or absorbed dose, while hypothyroidism follows a linear relationship. The effect of including or omitting factors in the calculation of the administered I–131 activity such as the measured thyroid uptake and effective half-life of RaI or giving extra compensation for gland size is discussed.

Conclusions

Very little benefit can be gained by employing complicated methods of RaI dose selection for non-ablative therapy since the standard activity model shows the best potential for cure and prolonged euthyroidism. For ablative therapy, a standard MBq/g dosing provides the best outcome in terms of cure and early hypothyroidism.  相似文献   
3.
4.
Introduction  We evaluated the demographics, flap types, and 30-day complication, readmission, and reoperation rates for upper extremity free flap transfers within the National Surgical Quality Improvement Program (NSQIP) database. Materials and Methods  Upper extremity free flap transfer patients in the NSQIP from 2008 to 2016 were identified. Complications, reoperations, and readmissions were queried. Chi-squared tests evaluated differences in sex, race, and insurance. The types of procedures performed, complication frequencies, reoperation rates, and readmission rates were analyzed. Results  One-hundred-eleven patients were selected (mean: 36.8 years). Most common upper extremity free flaps were muscle/myocutaneous (45.9%) and other vascularized bone grafts with microanastomosis (27.9%). Thirty-day complications among all patients included superficial site infections (2.7%), intraoperative transfusions (7.2%), pneumonia (0.9%), and deep venous thrombosis (0.9%). Thirty-day reoperation and readmission rates were 4.5% and 3.6%, respectively. The mean time from discharge to readmission was 12.5 days. Conclusion  Upper extremity free flap transfers could be performed with a low rate of 30-day complications, reoperations, and readmissions.  相似文献   
5.

Background

Inflammation and pain underlies several pathological conditions. Synthetic drugs used for the management of these conditions carry severe toxic effects. Globally efforts are ongoing to introduce novel medicinal plants to develop effective, economic and innocuous drugs. The current study was aimed at investigating the antipyretic, anti-inflammatory and analgesic activity of methanol extract of A. hydaspica aerial parts (AHM) and its active fraction. Furthermore identification and isolation of polyphenolic compounds was carried out to identify the active principles.

Methods

Yeast induced pyrexia, Paw edema, acetic acid-induced writhing and hot plate test were carried out in vivo. HPLC-DAD analysis and combination of different chromatographic techniques, involving vacuum liquid chromatography (VLC) and flash chromatography (FC) were carried out for chemical characterization. The structural heterogeneity of flavanols was characterized by ESI- MS, 1H NMR, 13C NMR and 2D NMR spectroscopic analyses, and also by comparison with reported literature.

Results

Oral administration of A. hydaspica methanol extract (AHM) and A. hydaspica ethyl acetate fraction (AHE), showed dose and time dependent decrease in body temperature in yeast induced pyrexia, comparable to standard, Paracetamol. AHM and AHE (150 mg/kg) significantly (p?<?0.001) inhibit pain sensation in various pain models, i.e. acetic acid induced writhing and hot plate test. Similarly AHM and AHE demonstrated an anti-inflammatory effect in carrageenan-induced paw edema in rats and 150 mg/kg dose being distinctly more effective (91.92% inhibition). When studied on prostaglandin E2 (PGE2) induced edema in rats, AHM and AHE showed maximum inhibition of edema at 150 mg/kg after 4 h. HPLC chromatogram of AHM revealed the presence of gallic acid, catechin, rutin and caffeic acid. Chromatographic separation and structure characterization of AHE, has led to the identification of three flavan-3-ol derivative including 7-O-galloyl catechin, +catechin and methyl gallate, which have been reported for the first time in A. hydaspica.

Conclusion

These results revealed that the presence of bioactive compounds in A. hydaspica might be responsible for the pharmacological activities, confirming the indigenous utility of A. hydaspica against inflammatory disorders.
  相似文献   
6.

BACKGROUND:

Recent developments may alter the approach to patients presenting with gastroesophageal reflux disease (GERD)-like symptoms. A newly proposed Montreal consensus definition of Barrett’s esophagus includes all types of esophageal columnar metaplasia, with or without intestinal-type metaplasia. There is also increasing recognition of eosinophilic esophagitis (EE) in patients with GERD-like symptoms.

OBJECTIVE:

To quantify the impact of these developments on a multiphysician general gastroenterology practice in a tertiary care medical centre.

METHODS:

Medical charts of all patients having an initial gastroscopy for GERD-like symptoms over a one-year period were reviewed retrospectively, and audits of their endoscopic images and esophageal biopsies were performed.

RESULTS:

Of the 353 study participants, typical symptoms of heartburn and acid reflux were present in 87.7% and 23.2%, respectively. Less commonly, patients presented with atypical symptoms (eg, dysphagia in 9.4%). At endoscopy, 26% were found to have erosive esophagitis and 12% had endoscopically suspected esophageal metaplasia. Histological evaluation was available for 65 patients. Ten of the 65 biopsied patients (15%) met traditional criteria for Barrett’s esophagus (ie, exhibiting intestinal-type metaplasia), whereas 49 (75%) fulfilled the newly proposed consensus definition of Barrett’s esophagus. Five patients (7.7%) met the study criteria for EE (more than 20 eosinophils per high-power field), four of whom had not been previously recognized.

CONCLUSIONS:

Among patients presenting with GERD-like symptoms, the prevalence of Barrett’s esophagus may increase markedly if the Montreal definition is adopted. In addition, growing awareness of EE may lead to an increase in the prevalence of this diagnosis. Prospective studies of the management implications of these findings are warranted.  相似文献   
7.
8.
Singh  J.  Cerghet  M.  Poisson  L. M.  Datta  I.  Labuzek  K.  Suhail  H.  Rattan  R.  Giri  Shailendra 《Journal of neuroimmune pharmacology》2019,14(2):241-250

Identification of non-invasive biomarkers of disease progression in multiple sclerosis (MS) is critically needed for monitoring the disease progression and for effective therapeutic interventions. Urine is an attractive source for non-invasive biomarkers because it is easily obtained in the clinic. In search of a urine metabolite signature of progression in chronic experimental autoimmune encephalomyelitis (EAE), we profiled urine at the chronic stage of the disease (day 45 post immunization) by global untargeted metabolomics. Using a combination of high-throughput liquid-and-gas chromatography with mass spectrometry, we found 105 metabolites (P < 0.05) significantly altered at the chronic stage, indicating a robust alteration in the urine metabolite profile during disease. Assessment of altered metabolites against the Kyoto Encyclopedia of Genes and Genomes revealed distinct non-overlapping metabolic pathways and revealed phenylalanine-tyrosine and associated metabolism being the most impacted. Combined with previously performed plasma profiling, eight common metabolites were significantly altered in both of the biofluids. Metaboanalyst analysis of these common metabolites revealed that phenylalanine metabolism and Valine, leucine, and isoleucine biosynthetic pathways are central metabolic pathways in both bio-fluids and could be analyzed further, either for the discovery of therapeutics or biomarker development. Overall, our study suggests that urine and plasma metabolomics may contribute to the identification of a distinct metabolic fingerprint of EAE disease discriminating from the healthy control which may aid in the development of an objective non-invasive monitoring method for progressive autoimmune diseases like MS.

Untargeted urinary metabolomics of a chronic mouse model of multiple sclerosis identified Phenylalanine, tyrosine & tryptophan metabolism as the significantly altered metabolic pathway. Eight common metabolites were identified when we combined urinary and plasma metabolic signature, which revealed a perturbation of Phenylalanine metabolism and valine, leucine & isoleucine metabolic pathways, involved in CNS dysfunction during diseases. The identified eight metabolic signature of urine and plasma may be of clinical relevance as potential biomarkers and guide towards the identification of specific metabolic pathways as novel drug targets.

  相似文献   
9.
10.
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