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   2653篇
  免费   151篇
  国内免费   3篇
耳鼻咽喉   24篇
儿科学   98篇
妇产科学   71篇
基础医学   426篇
口腔科学   90篇
临床医学   227篇
内科学   541篇
皮肤病学   46篇
神经病学   193篇
特种医学   100篇
外科学   449篇
综合类   37篇
预防医学   77篇
眼科学   38篇
药学   140篇
中国医学   5篇
肿瘤学   245篇
  2023年   11篇
  2022年   26篇
  2021年   51篇
  2020年   36篇
  2019年   59篇
  2018年   57篇
  2017年   37篇
  2016年   43篇
  2015年   49篇
  2014年   100篇
  2013年   135篇
  2012年   148篇
  2011年   183篇
  2010年   94篇
  2009年   114篇
  2008年   140篇
  2007年   147篇
  2006年   139篇
  2005年   119篇
  2004年   122篇
  2003年   111篇
  2002年   115篇
  2001年   92篇
  2000年   68篇
  1999年   72篇
  1998年   29篇
  1997年   35篇
  1996年   24篇
  1995年   23篇
  1994年   26篇
  1993年   23篇
  1992年   35篇
  1991年   24篇
  1990年   44篇
  1989年   42篇
  1988年   21篇
  1987年   25篇
  1986年   17篇
  1985年   19篇
  1984年   13篇
  1983年   8篇
  1981年   7篇
  1978年   7篇
  1977年   6篇
  1976年   6篇
  1974年   7篇
  1973年   6篇
  1970年   7篇
  1952年   16篇
  1951年   23篇
排序方式: 共有2807条查询结果,搜索用时 15 毫秒
121.
122.
Conventional treatment of an infected aortobifemoral graft includes total graft excision and ex situ bypass grafting, but has been associated with significant perioperative morbidity and mortality. Additionally, the presence of infection in the groin makes limb revascularization problematic. There is increasing evidence that in situ replacement of an infected graft can achieve promising results in selected patients. We present a case of an aortobifemoral graft infection, affecting both the groin as well as the entire pelvis. The patient underwent successful in situ graft replacement with a new aortobipopliteal prosthesis via an alternative extraperitoneal route.  相似文献   
123.
目的观察艾瑞昔布超前镇痛用于脊柱手术对患者术后镇痛效果的影响。方法选取本院2017年3月~2018年3月收治的110例脊柱手术患者,按随机数表法分为观察组与对照组,各55例。观察组术前30 min口服100 mg的艾瑞昔布,对照组口服相同剂量的安慰剂。术毕予负荷剂量的芬太尼0.001 mg/kg。比较两组术后6 h与12 h的疼痛程度[采用视觉模拟评分法(VAS)评估]、镇静效果(采用Ramesay评分法评估)、芬太尼消耗量、自控按压总次数、不良反应总发生率。结果观察组术后6 h与术后12 h的术后疼痛VAS评分分别为(2.80±0.82)分与(1.85±0.45)分,低于对照组的(3.15±0.91)分与(2.32±0.64)分;观察组的镇静Ramesay评分分别为(2.28±0.59)分与(2.06±0.58)分,低于对照组的(2.63±0.71)分与(2.33±0.70)分,差异有统计学意义(P0.05)。观察组术后0~6 h、6~12 h、12~24 h的芬太尼消耗量及自控按压总次数均低于对照组(P0.05)。观察组的不良反应总发生率为7.27%,低于对照组的21.82%(P0.05)。结论脊柱手术患者采用艾瑞昔布进行超前镇痛可获得良好的术后镇痛效果与镇静效果,芬太尼用量与不良反应均明显减少,具有较高的有效性与安全性,值得推广。  相似文献   
124.
125.
A case report is presented of a rapidly growing congenital nasopharyngeal teratoma (epignathus) in a preterm infant, leading to severe upper airway obstruction. Prenatal diagnosis by ultrasonography did not reveal the condition because the tumour masses were initially small and there was no polyhydramnios. Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period and should be treated surgically.
Conclusion:  Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period.  相似文献   
126.
Background Rhinoviruses (RVs) are responsible for the majority of acute asthma and chronic obstructive pulmonary disease (COPD) exacerbations. RVs infect the lower airways and induce the production of pro-inflammatory and remodelling-associated mediators. Budesonide (BUD) and formoterol (FORM) synergize in controlling asthma and COPD exacerbations; however, their effects on virus-induced inflammation and remodelling are less known.
Objective We investigated whether BUD and FORM synergize in suppressing RV-induced inflammation and remodelling in the airways.
Methods In vitro models of RV infection of BEAS-2B and primary normal human bronchial epithelial (NHBE) cells were used. We assessed the effects of individual and combined drugs administered post-infection, at a clinically relevant concentration range (10−6–10−10  m ), on the production of CCL5, CXCL10, CXCL8, IL-6 and the remodelling-associated VEGF and bFGF, using ELISA and RT-PCR.
Results BUD effectively suppressed RV-mediated induction of all mediators studied, in a concentration-dependent manner. FORM alone suppressed the production of CXCL8 and bFGF. The combination of BUD and FORM had concentration-dependent, additive or synergistic effects in the suppression of RV-induced CCL5, CXCL8 and CXCL10 in both cell types as well as VEGF in NHBE only. Combination treatment also resulted in an enhanced suppression of RV-induced IL-6, and CCL5 at the mRNA level as compared with BUD or FORM alone.
Conclusion BUD and FORM suppress RV-induced chemokines and growth factors in bronchial epithelial cells in a concentration-dependent, synergistic or additive manner. These data further support the combined use of BUD and FORM in asthma and COPD and intensification of this therapy during exacerbations.  相似文献   
127.
This the case of a 63 year-old man with end-stage renal disease (on chronic hemodialysis), unstable angina and significantly impaired myocardial contractility with low left ventricular ejection fraction, who underwent off-pump one vessel coronary bypass surgery. Combined continuous levosimendan and norepinephrine infusion (at 0.07 μg/kg/min and 0.05 μg/kg/min respectively) started immediately after anesthesia induction and continued for 24 hours. The levosimendan/norepinephrine combination helped maintain an appropriate hemodynamic profile, thereby contributing to uneventful completion of surgery and postoperative hemodynamic stability. Although levosimendan is considered contraindicated in ESRD patients, this case report suggests that combined perioperative levosimendan/norepinephrine administration can be useful in carefully selected hemodialysis patients with impaired myocardial contractility and ongoing myocardial ischemia, who undergo off-pump myocardial revascularization surgery.  相似文献   
128.
129.
A high proportion of extranodal lymphoid infiltrates are diffuse small lymphocytic proliferations [1, 2] and therefore pose a particularly challenging diagnostic problem [1-4]. Their benign or malignant nature cannot be determined using clinical and radiologic criteria. The application of traditional morphologic criteria (i.e., cytologic maturity and polymorphism favor benignancy, while cytologic atypia and monomorphism favor malignancy) [5, 6], has probably improved diagnostic accuracy. However, these criteria generally have not been helpful in evaluating the large number of lymphoid infiltrates composed of monomorphic collections of small cytologically-mature appearing lymphoid cells [1-4] and, therefore, have not always accurately predicted clinical behavior. Extranodal lymphoid proliferations are also of considerable biologic interest since their pathogenesis and natural history have not been fully elucidated. Localized non-Hodgkin's lymphoma, extranodal-MALT-type. was diagnosed in our Department in three cases: Two arose in the orbit and the third one in the tonsil. The tumors had a typical histologic appearance. The microscopical features and immunohistochemical profile are discussed.  相似文献   
130.
头孢克肟胶囊人体药动学研究及生物等效性评价   总被引:1,自引:0,他引:1  
目的:研究头孢克肟胶囊在健康人体内的药动学及生物等效性。方法:以18名健康志愿者为试验对象,采用同体交叉试验方法,分别单剂量口服受试制剂或参比制剂各400mg,采用HPLC法测定血浆中药物浓度。结果:参比制剂和受试制剂的tmax分别为(3.39±0.50)和(3.39±0.50)h,cmax分别为(2.33±0.33)和(2.27±0.25)μg/mL,t1/2分别为(3.92±0.85)和(4.41±0.68)h,AUC0~16分别为(14.61±2.67)和(14.82±2.02)μg·h·mL^-1,AUC0~∞分别为(16.00±3.13)和(16.81±2.62)μg·h·mL^-1。结论:受试制剂与参比制剂生物等效,受试制剂的相对生物利用度为(98.69±13.13)%。  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