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   2798篇
  免费   76篇
  国内免费   25篇
耳鼻咽喉   179篇
儿科学   95篇
妇产科学   113篇
基础医学   184篇
口腔科学   66篇
临床医学   226篇
内科学   666篇
皮肤病学   30篇
神经病学   171篇
特种医学   169篇
外科学   663篇
综合类   24篇
预防医学   60篇
眼科学   81篇
药学   102篇
中国医学   3篇
肿瘤学   67篇
  2024年   2篇
  2023年   14篇
  2022年   25篇
  2021年   50篇
  2020年   36篇
  2019年   47篇
  2018年   65篇
  2017年   57篇
  2016年   76篇
  2015年   82篇
  2014年   126篇
  2013年   172篇
  2012年   228篇
  2011年   196篇
  2010年   132篇
  2009年   137篇
  2008年   217篇
  2007年   235篇
  2006年   220篇
  2005年   240篇
  2004年   193篇
  2003年   134篇
  2002年   109篇
  2001年   13篇
  2000年   12篇
  1999年   5篇
  1998年   13篇
  1997年   14篇
  1996年   11篇
  1995年   5篇
  1994年   8篇
  1993年   7篇
  1992年   3篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   2篇
  1987年   2篇
  1985年   3篇
  1983年   1篇
  1980年   1篇
  1976年   1篇
  1967年   1篇
排序方式: 共有2899条查询结果,搜索用时 15 毫秒
71.
AIMS: This study was undertaken to compare periodontal conditions, gingival crevicular fluid (GCF) levels of tissue-type plasminogen activator (t-PA), its inhibitor plasminogen activator inhibitor-2 (PAI-2), interleukin-1beta (IL-1beta), prostaglandin E(2) (PGE(2)) in rheumatoid arthritis (RA) patients and control groups. METHODS: Twenty-three RA patients, 17 systemically healthy patients with periodontal disease (PD), and 17 systemically and periodontally healthy subjects were recruited. GCF samples were obtained from two single-rooted teeth. Full-mouth clinical periodontal measurements were recorded at six sites/tooth. GCF samples were analysed using relevant ELISA kits. Data were tested statistically by appropriate tests. RESULTS: Total amounts of t-PA, PAI-2 and PGE(2) in GCF samples of the healthy control group were significantly lower than the other groups (p<0.05). The RA group exhibited a higher total amount of t-PA in GCF samples than the PD group (p<0.05). PAI-2, IL-1beta and PGE(2) total amounts were similar in RA and PD groups (p>0.05). CONCLUSION: The coexistence of RA and periodontitis does not seem to affect clinical periodontal findings or systemic markers of RA. Similar inflammatory mediator levels in RA and PD groups, despite the long-term usage of corticosteroids, non-steroidal anti-inflammatory drugs, suggest that RA patients may have a propensity to overproduce these inflammatory mediators.  相似文献   
72.
73.
74.
75.
76.
Late potentials (LP) detected on the signal-averaged electrocardiogram (SAECG) predict arrhythmic events after acute myocardial infarction (AMI). It is also well established that successful thrombolytic therapy reduces the incidence of LP. Our aim was to evaluate the effects of a beta-blocker on LP in patients receiving thrombolytic therapy. We studied 40 patients presenting with anteroseptal AMI (< 6 hours). All patients received thrombolytic therapy and were evaluated with coronary angiography at predischarge. Eighteen patients received metoprolol (5 mg IV on admission followed by 50 mg BID). SAECG recordings were obtained serially using an ART system (40-250 Hz filter, noise < 0.5 mV) prior to thrombolytic therapy, after 48 hours and after 10 days. LP was defined as posi-tive if the SAECG met at least 2 of the Gomes criteria. Changes observed in SAECG recordings after thrombolytic therapy were correlated with angiographic and clinical data with regard to the usage of BB. The frequencies of LP before and after thrombolytic therapy were compared with the McNemar test. There were no significant differences between the clinical characteristics, risk factors, and angiographic findings (including infarct related artery patency and LV functions) of the groups. Baseline SAECG findings were also similar between the groups. The incidence of LP significantly decreased after TT in the BB group, however, this change was not observed in patients who did not receive BB (P = 0.012, McNemar test). Beta-blockers reduce the incidence of LPs following thrombolytic therapy in patients with anterior AMI. This might be explained by the possible beneficial effect of BB on the arrhythmogenic substrate.  相似文献   
77.
78.
OBJECTIVE: To describe a case of hepatotoxicity associated with phenyramidol use that resolved after discontinuation of the drug. BACKGROUND: Phenyramidol is a moderately potent and relatively nontoxic analgesic with concomitant muscle-relaxant activity. A MEDLINE search in June 2003 revealed no reports associating hepatotoxicity with this agent. CASE SUMMARY: A 70-year-old man was investigated because of elevated liver function test values on routine biochemical screening. He had no clinical symptoms. Other etiologies of hepatitis were appropriately ruled out, and elevated enzymes were ascribed to phenyramidol treatment. DISCUSSION: This is the first case published in the English language literature describing probable hepatotoxicity, according to the Naranjo probability scale, resulting from use of phenyramidol. The mechanism of phenyramidol-induced liver damage is unknown. Several features, such as the absence of predictable dose-dependent toxicity of phenyramidol in previous studies and the absence of hypersensitivity manifestations in our patient, are suggestive of a metabolic type of idiosyncratic toxicity. CONCLUSIONS: Phenyramidol should be considered as a drug that possibly causes hepatotoxicity.  相似文献   
79.
Surgical treatment of axillary artery aneurysm   总被引:2,自引:0,他引:2  
Aneurysms of the axillary artery are rare and dangerous lesions that threaten the upper extremities with vascular and neurologic compromise. Most can be treated effectively with surgical excision and vascular grafting. We retrospectively assessed 4 axillary artery aneurysms upon which we operated from February 1998 through March 2004. Three patients were admitted to our clinic for symptomatic axillary masses. The remaining patient was transported to our clinic emergently due to massive hemorrhage of an enlarging axillary mass that occurred during biopsy of the mass at another hospital. In this patient, the ruptured axillary artery aneurysm was diagnosed by means of emergent upper-extremity selective angiography. All patients were treated surgically by means of aneurysmectomy and graft interpositioning--with polytetrafluoroethylene grafts in 2 patients and saphenous vein grafts in the other 2. Surgical treatment of axillary artery aneurysms is of importance in avoiding thromboembolism and ischemia, which in turn can lead to gangrene and amputation of the affected extremity. For this reason, operative management of such cases should not be delayed.  相似文献   
80.
There is a little information in literature about circulating asymmetric dimethylarginine (ADMA) concentrations in polycystic ovary syndrome (PCOS) and the results reported are discrepant. In this study, therefore, we aimed (1) to determine the circulating ADMA concentrations in 44 women with PCOS and 22 age- and BMI-matched healthy controls, (2) to evaluate its correlations with insulin resistance, gonadotrophins, and androgen secretion, and (3) to compare effects of metformin and ethinyl estradiol-cyproterone acetate (EE/CPA) treatments on circulating ADMA concentrations. In conclusion, our data indicate that circulating ADMA concentrations in non-obese, non-hypertensive and young women with PCOS are significantly higher than healthy controls and they improved by a 3-month course of metformin and oral contraceptive treatments.  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