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   476篇
  免费   30篇
  国内免费   1篇
耳鼻咽喉   3篇
儿科学   10篇
妇产科学   5篇
基础医学   66篇
口腔科学   9篇
临床医学   31篇
内科学   108篇
皮肤病学   7篇
神经病学   28篇
特种医学   12篇
外科学   97篇
综合类   15篇
预防医学   22篇
眼科学   6篇
药学   51篇
中国医学   3篇
肿瘤学   34篇
  2023年   4篇
  2022年   6篇
  2021年   17篇
  2020年   10篇
  2019年   14篇
  2018年   12篇
  2017年   5篇
  2016年   15篇
  2015年   13篇
  2014年   14篇
  2013年   30篇
  2012年   28篇
  2011年   30篇
  2010年   25篇
  2009年   24篇
  2008年   39篇
  2007年   31篇
  2006年   38篇
  2005年   18篇
  2004年   21篇
  2003年   11篇
  2002年   14篇
  2001年   17篇
  2000年   13篇
  1999年   7篇
  1998年   4篇
  1997年   5篇
  1996年   4篇
  1995年   9篇
  1994年   1篇
  1992年   4篇
  1991年   3篇
  1990年   1篇
  1989年   3篇
  1987年   2篇
  1985年   4篇
  1984年   3篇
  1983年   3篇
  1981年   1篇
  1980年   2篇
  1979年   1篇
  1978年   1篇
排序方式: 共有507条查询结果,搜索用时 890 毫秒
11.
12.

Background  

The sensitivity and specificity of 18S rRNA polymerase chain reaction (PCR) in the detection of fungal aetiology of microbial keratitis was determined in thirty patients with clinical diagnosis of microbial keratitis.  相似文献   
13.
The stimulatory and inhibitory effects on testicular steroidogenesis of transient neonatal hypothyroidism from day 1 postpartum through different postnatal developmental events on testis at puberal age (60 days old) were studied in vivo. Hypothyroidism was induced in neonates by feeding the lactating mother or directly with 0.05% methimazole (MMI) through drinking water from the day of parturition to 10, 15, 30, 40 and 60 days, and were killed at day 60 postpartum. Plasma and testicular interstitial fluid (TIF) progesterone, testosterone, dihydrotestosterone (DHT) and estradiol concentrations were assessed. Testis weight and volume significantly increased in rats subjected to 10 and 15 days of hypothyroidism, decreased in rats subjected to 30, 40 and 60 days of hypothyroidism. A consistent increase in Leydig cell number was seen in puberal rats subjected to transient neonatal hypothyroidism but decreased in 60 days hypothyroid rats. Peritubular myoid cell number was consistently decreased in all experimental rats. Leydig cell diameter decreased consistently in all experimental groups. Persistent hypothyroidism (60 days hypothyroid) consistently decreased both plasma and TIF sex steroids. In transient hypothyroid rats, progesterone concentration decreased in both plasma and TIF. Transient hypothyroidism from birth to day 10 postnatal age maintained normal titre of plasma testosterone, whereas a significant increase in TIF testosterone concentration was evident when compared with controls. All other groups of rats subjected to transient neonatal hypothyroidism had consistently low titres of plasma and TIF testosterone. Plasma DHT concentrations in rats subjected to transient neonatal hypothyroidism remained unaltered. However, TIF DHT increased in 10 days  相似文献   
14.
15.
The objective of this study was to perform a systematic literature review to describe patient outcome after total knee arthroplasty revision procedures using various global knee score ratings. English language articles published from 1966 through 2000 were identified through a computerized literature search and bibliography review. A multistage assessment was used to determine the articles containing data that could meet our objective. Meta-analyses of global knee scores were undertaken using a fixed effects model with the assumption that the variances of each individual measurement were identical across studies. The initial inclusion criteria were met by 58 articles with a total of 1,965 patients. There were 42 articles comprising 45 unique patient cohorts and a total of 1,515 patients that had sufficient global knee score data for analysis and were used in the meta-analyses. Revision total knee arthroplasty is an effective procedure for failed knee arthroplasties based on global knee rating scales.  相似文献   
16.
Missed and mismanaged injuries of the spinal cord   总被引:3,自引:0,他引:3  
OBJECTIVE: The purpose of this study was to determine the incidence of missed and mismanaged injuries of the spinal cord, to identify factors contributing to a failure to recognize such injuries, and to assess the consequences of such failures. METHODS: Missed and mismanaged injuries were defined using previously validated statements. All medical records and radiographs of patients with acute traumatic spinal cord injury admitted to the Regional Spinal Cord Injury Unit in Sheffield, United Kingdom, over a period of 10 years from 1989 were evaluated. Patients with no neurologic deficits were excluded from the study. RESULTS: Of the 569 patients, the diagnosis of spinal cord injury was missed in 52 instances (9.1%). The patients were mismanaged in 34 instances, and the treatment offered to 30 was considered negligent. In 26 of 52 (50%), mismanagement resulted in neurologic deterioration. The study identified several factors that contributed to a failure to recognize a spinal cord injury. These include ambience and circumstances surrounding the injury, inadequate neurologic assessment, associated injuries, and radiographic errors. CONCLUSION: Despite a greater awareness of the potential for spinal injury after road traffic accidents, failure to recognize a spinal cord injury in the acute care setting appears to be increasing. Injuries are seldom missed because of an isolated cause, but rather because of a combination of several factors. Increased vigilance on the part of the primary care physicians and careful documentation may reduce allegations of medical negligence.  相似文献   
17.
BACKGROUND: A number of experimental studies have shown that increasing glucose use or decreasing accumulation of long-chain acyl carnitines (LCAC) protect ischemic hearts. METHODS: To evaluate the relative importance of these two strategies in protecting ischemic myocardium, isolated rat hearts (n = 6 in each group) were paced at 300 bpm and subjected to 50 min of low-flow ischemia followed by 60 min of reperfusion. Buffer contained 0.4 m mol/l albumin, 0.4 m mol/l palmitate, and 70 mU/l insulin, and either normal glucose (5 m mol/l) (CON), high glucose (10 m mol/l total) (HG, known to increase glucose use), 5 m mol/l glucose and niacin (10 micromol/l) (NIA, known to increase glucose use and decrease LCAC) or carnitine (10 m mol/l) (CAR, known to increase glucose use and decrease LCAC). Separate groups of hearts were perfused in the presence of 10 micromol/l cytochalasin-B (CB), an inhibitor of insulin-sensitive glucose transporters. RESULTS: Ischemic injury, as assessed by creatine kinase (CK) release was diminished by an average of 50% in HG, NIA, and CAR hearts, and the percentage recovery of left ventricular (LV) function with reperfusion was enhanced by approximately 20% compared with CON hearts (P < 0.05 for each comparison). Cytochalasin-B abolished all of the salutary effects. Long-chain acyl carnitines levels were higher in HG hearts compared with NIA- and CAR-treated hearts ( P < 0.05), but ischemic protection and functional recovery was greater in HG hearts. CONCLUSIONS: The data support the adjunctive use of agents that promote glucose uptake during ischemia and suggest that increasing glucose use is more important than decreasing LCAC in the protection against ischemic injury or in the recovery of contractile function.  相似文献   
18.
Cystic breast masses are a common presentation to breast clinics. While the majority of cysts can be managed by simple aspiration, a small proportion are malignant. Histology records for a 10-year period have been examined to identify patients with cystic breast carcinomas. In all, 31 patients were identified. Of these, 18 had cystic degeneration of high-grade tumours, while 13 had intracystic papillary carcinoma. Both of these tumour types were diagnosed by a combination of cyst fluid cytology and breast imaging. The prognosis of high-grade tumours was poor, while that of intracystic papillary carcinomas was excellent. After cyst aspiration, bloodstained fluid should be sent for cytology and breast imaging arranged in all patients. Patients in whom a cyst refills within 2 week of aspiration require a careful re-evaluation. Cysts in postmenopausal women should be viewed with suspicion. Excision should be performed in patients with positive cytology or imaging.  相似文献   
19.
Double-filtration plasmapheresis (DFPP) and splenectomy prior to transplant is used in a few centers for high-risk transplantations. We undertook a prospective study to examine the outcome of 16 kidney transplantations in crossmatch-positive patients using splenic radiation and DFPP as pretransplant immunomodification procedures. All patients received a single dose of Zenapax (50 mg intravenously [IV] 8 hours before transplant), before treatment with cyclosporine, mycophenolate mofetil, and steroids immediately posttransplant. Follow-up ranged from 3 months to 1 year. Hyperacute rejection requiring graft nephrectomy was necessary in one patient; acute rejection, which was seen in three patients, was reversed with five doses of Iort3 at 1-month posttransplant the mean creatinine was 1.3 +/- 0.6 mg/dL in patients who did not have rejection and 1.9 +/- 0.3 mg/dL in the three patients who had acute rejection. Six patients were switched from cyclosporine to sirolimus. At the end of 3 months the mean creatinine levels was 1.4 +/- 0.3 mg%. The infections included oral candida (n = 2), urinary tract infection (UTI) (n = 1), bacterial pneumonia (n = 1), and herpes zoster (n = 1). With the advent of modern immunosuppressants, pretransplant immunomodification with DFPP and splenic radiation is safe and effective. Splenic radiation is devoid of surgical risk and more acceptable to patients.  相似文献   
20.
High fructose feeding in rats induces insulin resistance, hyperinsulinemia, hyperglycemia and dyslipidemia. The present study was undertaken to determine the hypolipidemic effect of food seasoning spices mixture on fructose-fed insulin resistant rats. Male Wistar rats received a daily diet containing either 60% fructose or 60% starch. They were administered with the spices mixture at three different doses (10 mg, 30 mg or 50 mg/day/rat) orally 15 days later. At the end of 45 days of the experimental period fructose-fed rats displayed elevated plasma glucose and insulin levels and dyslipidemia which included elevated levels of cholesterol, triglycerides, free fatty acids, reduced high density lipoprotein cholesterol and increased very low density lipoprotein cholesterol. Alterations in tissue lipid levels were also observed. Simultaneous treatment with spices mixture along with fructose diet resulted in the normalization of plasma glucose and insulin levels and restoration of lipid levels in plasma and tissues. The insulin potentiating action of the active principles in these spices may contribute to the hypolipidemic effect of spices mixture in high fructose-fed rats.  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