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   900篇
  免费   33篇
  国内免费   7篇
耳鼻咽喉   9篇
儿科学   29篇
妇产科学   35篇
基础医学   95篇
口腔科学   15篇
临床医学   70篇
内科学   171篇
皮肤病学   9篇
神经病学   57篇
特种医学   25篇
外科学   139篇
综合类   49篇
预防医学   57篇
眼科学   39篇
药学   98篇
中国医学   4篇
肿瘤学   39篇
  2023年   6篇
  2022年   27篇
  2021年   25篇
  2020年   23篇
  2019年   24篇
  2018年   33篇
  2017年   23篇
  2016年   23篇
  2015年   25篇
  2014年   24篇
  2013年   45篇
  2012年   83篇
  2011年   57篇
  2010年   35篇
  2009年   27篇
  2008年   32篇
  2007年   41篇
  2006年   35篇
  2005年   42篇
  2004年   45篇
  2003年   39篇
  2002年   31篇
  2001年   26篇
  2000年   32篇
  1999年   26篇
  1998年   8篇
  1997年   6篇
  1995年   2篇
  1992年   7篇
  1991年   3篇
  1990年   9篇
  1989年   2篇
  1988年   5篇
  1987年   6篇
  1986年   12篇
  1985年   9篇
  1979年   5篇
  1977年   1篇
  1976年   1篇
  1975年   3篇
  1974年   3篇
  1973年   2篇
  1972年   3篇
  1971年   3篇
  1970年   7篇
  1969年   1篇
  1968年   2篇
  1967年   2篇
  1966年   1篇
  1965年   2篇
排序方式: 共有940条查询结果,搜索用时 0 毫秒
81.
82.
Retinopathy of Prematurity (ROP) is one of the leading causes of bilateral blindness in childhood. Early detection and effective treatment can prevent blindness. Efficient and timely screening examination of the retina by an experienced ophthalmologist who deals with preterm neonates with ROP is the mainstay in the management of this disease. All neonatologists and pediatricians who care for these at-risk preterm neonates should also be aware of this timing. This practical guideline intends to provide guidance to ophthalmologists, neonatologists and allied health care professionals in Saudi Arabia on current indications for screening and management of retinopathy of prematurity to prevent or minimize subsequent complications. This practical guideline was led by the National Eye Health Program (NEHP) and Neonatology Services Improvement Program at Ministry of Health (MOH), furthermore it has been solicited and endorsed from both Saudi Ophthalmological Society (SOS) and Saudi Neonatology Society (SNS).  相似文献   
83.
Current guidelines recommend deferring liver transplantation (LT) in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection until clinical improvement occurs and two PCR tests collected at least 24 hours apart are negative. We report a case of an 18-year-old, previously healthy African-American woman diagnosed with COVID-19, who presents with acute liver failure (ALF) requiring urgent LT in the context of SARS-CoV-2 polymerase chain reaction (PCR) positivity. The patient was thought to have acute Wilsonian crisis on the basis of hemolytic anemia, alkaline phosphatase:bilirubin ratio <4, AST:ALT ratio >2.2, elevated serum copper, and low uric acid, although an unusual presentation of COVID-19 causing ALF could not be excluded. After meeting criteria for status 1a listing, the patient underwent successful LT, despite ongoing SARS-CoV-2 PCR positivity. Remdesivir was given immediately posttransplant, and mycophenolate mofetil was withheld initially and the SARS-CoV-2 PCR test eventually became negative. Three months following transplantation, the patient has made a near-complete recovery. This case highlights that COVID-19 with SARS-CoV-2 PCR positivity may not be an absolute contraindication for transplantation in ALF. Criteria for patient selection and timing of LT amid the COVID-19 pandemic need to be validated in future studies.  相似文献   
84.
Bariatric surgery for morbid obesity has been established as an effective treatment method and has been shown to be associated with resolution of co-morbidities. Despite its success, some patients may require revision because of weight regain or mechanical complications. From September 2005 to December 2009, 42 patients underwent revisional Roux-en-Y gastric bypass (RYGB). All procedures were performed by one surgeon. Demographics, indications for revision, complications, and weight loss were reviewed. Thirty-seven patients were treated with laparoscopic (n = 36) or open (n = 1) RYGB after failed laparoscopic adjustable gastric banding. Four patient were treated with laparoscopic (n = 3) or open (n-1) RYGB after failed vertical banded gastroplasty, and one patient underwent open redo RYGB due to large gastric pouch. Conversion rate from laparoscopy to open surgery was 2.5% (one patient). Mean operative time was 145.83 ± 35.19 min, and hospital stay was 3.36 ± 1.20 days. There was no mortality. Early and late complications occurred in six patients (14.2%). The mean follow-up was 15.83 ± 13.43 months. Mean preoperative body mass index was 45.15 ± 7.95 that decreased to 35.23 ± 6.7, and mean percentage excess weight loss was 41.19 ± 20.22 after RYGB within our follow-up period. RYGB as a revisional bariatric procedure is effective to treat complications of restrictive procedures and to further reduce weight in morbidly obese patients.  相似文献   
85.
The case of a female with disseminated pelvic cystic hydatidosis presenting as ovarian carcinomatosis 2.5 years after repeated abdominal paracentesis is reported. The diagnosis was made during surgery and confirmed by serology and histological examination. Over 100 cysts were removed from the abdominal cavity and wall. Innumerable small cysts studded the viscera; these and larger inaccessible ones were untouched. Medical cure in this patient was achieved with a combination of partial resection and special irrigation, broad spectrum antibiotic for coverage of infectious episodes and high dose long term mebendazole therapy for 25 months. The danger of blind aspiration in patients coming from endemic areas is emphasized.  相似文献   
86.
Metformin has been shown to exert anti-neoplastic and chemopreventive activities in epidemiological and animal studies. This review article discusses the epidemiological studies and examines the possible mechanisms by which metformin exerts its anti-carcinogenic activities in breast, colon, ovarian, lung, and prostate cancers. We performed a systematic review of the clinical studies examining the anti-neoplastic activities of metformin and the potential mechanisms associated with these activities. Several observational and biological studies revealed a significant association between metformin and reduction in cancer incidence. The mechanisms by which metformin exerts these effects are unknown. This action may be mediated through activation of AMP-activated protein kinase (AMPK), inhibition of the mammalian target of rapamycin (mTOR) pathway, and inhibition of insulin like growth factors (IGFs), and many others. Further laboratory investigation and large, prospective population clinical trials are required to elucidate metformin anti-neoplastic and chemo-preventive actions.  相似文献   
87.
The efficacy of anticoagulants, low-molecular-weight heparins (LMWHs), the antiplatelet glycoprotein IIb/IIIa antagonist, or combinations on cancer-activated thrombosis was determined using thromboelastography. The LMWHs tinzaparin and enoxaparin (0.179, 1.79, 17.9 microg) were incubated in human citrated whole blood (n = 4) and then activated by calcium chloride (11 mmol/l) or Colo205 (cell count 10). Concentrations of 9.9, 17.9 and 179 microg glycoprotein IIb/IIIa antagonist, XV454, and combinations with each LMWH were carried out and activated under the same conditions. The experiment was repeated with tissue factor substituting for the Colo205 to induce platelet/fibrin clot formation. Parameters tested in the thrombelastography analysis included clotting time, rate of clot formation due to fibrin formation, clot kinetics, and clot strength related to platelet count (maximum amplitude). Tinzaparin (1.79 microg), enoxaparin (1.79 microg), and XV454 (17.9 microg) significantly reduced the angle by 64, 26 and 27%, respectively, in cancer-induced clotting. Significant reductions in the maximum amplitude occurred in tinzaparin 1.79 microg (31%), enoxaparin 1.79 microg (11%), and XV454 17.9 microg (59%). An overall antithrombotic additive effect occurred when each LMWH (1.79 microg) was combined with XV454 (17.9 microg). The results between cancer-activated and tissue factor-activated blood were similar. The study concludes that an additive effect is present between LMWHs and a glycoprotein IIb/IIIa antagonist in reducing cancer-mediated thrombosis.  相似文献   
88.
BACKGROUND: Pulmonary clearance of inhaled technetium (Tc) 99m-labeled diethylene triamine penta-acetic acid (DTPA) aerosol is a sensitive non-invasive marker of alveolar permeability and patients with interstitial lung diseases show enhanced clearance. However, a previous study in adult patients with diabetes mellitus showed delayed clearance. OBJECTIVES: To investigate DTPA clearance in steady-state, otherwise healthy adult sickle cell disease (SCD) patients and correlate it with pulmonary function tests (PFTs), hematologic and clinical parameters. MATERIALS AND METHODS: The subjects were randomly selected from the Hematology Clinic of Mubarak Hospital, Kuwait. Hematologic and pulmonary function data were collected with standard methods. DTPA radio-aerosol clearance studies were performed using ultrafine nebulizer containing 35 mCi (1295 MBq) of Tc 99m-DTPA in its reservoir and t(1/2) clearance in minutes was determined. Average values for both lungs were calculated and compared with normal values for our population. RESULTS: Forty-three subjects (24 SS and 19 S-beta(0)thal) aged between 16 and 45 yr (mean of 27.1 +/- 9.7) were studied. Twenty-two subjects (51.2%) had delayed, while only 10 (23.3%) showed enhanced DTPA clearance. Patients with enhanced clearance showed better PFTs than those with normal or delayed clearance. There was significant negative correlation of DTPA clearance with forced expiratory volume in 1 s, forced vital capacity and total lung capacity and significant positive correlation with age. CONCLUSIONS: Majority of adult SCD patients have delayed DTPA clearance unlike in inflammatory lung diseases, but similar to diabetes mellitus. DTPA clearance may be a useful modality for monitoring pulmonary involvement in SCD.  相似文献   
89.
Pseudoaneurysms in the external carotid artery system are rare, mostly reported in the superficial temporal and facial arteries. The bilateral sagittal split osteotomy has a low incidence of complications requiring emergency interventions. We report the case of a patient with acute bleeding from a pseudoaneurysm of the inferior alveolar artery diagnosed by angiography and treated successfully by super-selective embolization.  相似文献   
90.
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