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   2434篇
  免费   162篇
  国内免费   9篇
耳鼻咽喉   27篇
儿科学   83篇
妇产科学   56篇
基础医学   238篇
口腔科学   23篇
临床医学   317篇
内科学   417篇
皮肤病学   56篇
神经病学   161篇
特种医学   278篇
外科学   285篇
综合类   112篇
一般理论   2篇
预防医学   212篇
眼科学   22篇
药学   154篇
中国医学   2篇
肿瘤学   160篇
  2022年   23篇
  2021年   39篇
  2020年   29篇
  2019年   45篇
  2018年   40篇
  2017年   42篇
  2016年   33篇
  2015年   39篇
  2014年   76篇
  2013年   231篇
  2012年   106篇
  2011年   125篇
  2010年   59篇
  2009年   71篇
  2008年   88篇
  2007年   97篇
  2006年   96篇
  2005年   87篇
  2004年   71篇
  2003年   88篇
  2002年   62篇
  2001年   66篇
  2000年   90篇
  1999年   52篇
  1998年   31篇
  1997年   30篇
  1996年   42篇
  1995年   25篇
  1994年   32篇
  1993年   33篇
  1992年   48篇
  1991年   46篇
  1990年   45篇
  1989年   45篇
  1988年   37篇
  1987年   38篇
  1986年   53篇
  1985年   71篇
  1984年   19篇
  1983年   24篇
  1982年   19篇
  1981年   12篇
  1980年   12篇
  1979年   22篇
  1978年   11篇
  1975年   9篇
  1974年   16篇
  1973年   11篇
  1971年   11篇
  1970年   10篇
排序方式: 共有2605条查询结果,搜索用时 713 毫秒
1.
2.
3.
4.
青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究   总被引:1,自引:0,他引:1  
赵凯存  宣文漪  赵一  宋振玉 《药学学报》1989,24(11):813-816
将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5~4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。  相似文献   
5.
OBJECTIVE: Colonic infarction is a recognized complication of abdominal aortic aneurysm (AAA) surgery. The clinical difficulty in establishing the diagnosis combined with the patient's poor physiological status is usually associated with a fatal outcome. We assessed our experience with this problem to identify a possible risk factor profile for these patients. METHOD: Patients records were identified from the operative logs, intensive care unit, Hospital Inpatient Enquiry system and vascular unit databases over a 6-year period. RESULTS: A total of 405 patients underwent AAA repair during this period; 140 as emergency ruptures. Nine patients were identified from the databases with known colonic infarction (2.2%). One was a woman. The mean age was 70 years. Seven patients had emergency ruptures (5%). Twenty independent risk factors were analysed using univariate and multivariate logistic regression models. Significant risk factors identified by using a multivariate analysis included the nature of the presenting patient, preoperative hypotension, prolonged cross-clamp time, intra-operative ischaemia and postoperative acidosis. Confirmatory diagnosis was made by colonoscopy in eight patients. One patient survived following the salvage surgery. The mean duration of survival was 10.5 days. The overall mortality was 89% of patients. CONCLUSION: In our unit infrarenal AAA repair has a 2.2% rate of colonic infarction. A definitive diagnosis is best made by colonoscopy. A risk factor profile for the development of colonic infarction may be constructed on the basis of specific clinical parameters. Earlier intervention on the basis of this profile may ultimately reduce the current excessive mortality.  相似文献   
6.
7.
8.
INTRODUCTION: Concern about the potential detrimental side-effects of beta-blockade on pulmonary function often dissuades against their perioperative use in patients undergoing major arterial surgery (especially in those with chronic obstructive pulmonary disease (COPD)). In this study we aimed to establish prospectively the clinical relevance of these concerns. METHODS: After ethics committee approval and individual informed consent, the pulmonary function of twenty patients (mean age 68.7 years (range 43-82), 11 males) scheduled to undergo non-emergency major vascular surgery was studied by recording symptoms and spirometry before and after institution of effective beta-blockade. Fifteen patients (75%) had significant smoking histories (mean pack years/patient=50), while 12 (60%) had COPD. RESULTS: All patients tolerated effective beta-blockade satisfactorily without developing either subjective deterioration in symptoms or significant change on spirometry. The mean change in FEV1 following adequate beta-blockade was 0.05+/-0.24 liters (95% CI -0.06 to +1.61), p=0.35, giving a mean percentage change of 3.18%+/-11.66 (95% CI -2.26 to 8.62). CONCLUSIONS: Previously held concerns about worsening pulmonary function through the short-term use of beta-blockers should not dissuade their perioperative usage in patients with peripheral vascular disease. Furthermore, the accuracy of pulmonary function tests in preoperative assessment and risk stratification also appears unaffected by this therapy.  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