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   2436篇
  免费   131篇
  国内免费   44篇
耳鼻咽喉   15篇
儿科学   45篇
妇产科学   16篇
基础医学   97篇
口腔科学   15篇
临床医学   417篇
内科学   306篇
皮肤病学   3篇
神经病学   346篇
特种医学   50篇
外科学   569篇
综合类   352篇
预防医学   51篇
眼科学   31篇
药学   238篇
  2篇
中国医学   46篇
肿瘤学   12篇
  2023年   33篇
  2022年   47篇
  2021年   74篇
  2020年   76篇
  2019年   74篇
  2018年   63篇
  2017年   77篇
  2016年   62篇
  2015年   63篇
  2014年   122篇
  2013年   169篇
  2012年   101篇
  2011年   117篇
  2010年   93篇
  2009年   123篇
  2008年   114篇
  2007年   122篇
  2006年   98篇
  2005年   101篇
  2004年   71篇
  2003年   60篇
  2002年   59篇
  2001年   62篇
  2000年   40篇
  1999年   34篇
  1998年   37篇
  1997年   52篇
  1996年   27篇
  1995年   38篇
  1994年   31篇
  1993年   22篇
  1992年   31篇
  1991年   30篇
  1990年   29篇
  1989年   32篇
  1988年   14篇
  1987年   25篇
  1986年   23篇
  1985年   22篇
  1984年   32篇
  1983年   20篇
  1982年   23篇
  1981年   12篇
  1980年   10篇
  1979年   11篇
  1978年   8篇
  1977年   8篇
  1974年   3篇
  1973年   3篇
  1971年   3篇
排序方式: 共有2611条查询结果,搜索用时 93 毫秒
1.
Post-induction hypotension is common and associated with postoperative complications. We hypothesised that pneumatic leg compression reduces post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy. In this double-blind randomised study, patients were allocated randomly to the pneumatic leg compression group (n = 50) or control (n = 50). In the intervention group, pneumatic leg compression was initiated before induction of anaesthesia. In the control group, pneumatic leg compression was initiated 20 min after anaesthesia induction. The primary outcome was the incidence of post-induction hypotension in these groups. Post-induction hypotension was defined as systolic blood pressure < 90 mmHg during the first 20 min after induction. Haemodynamic variables and area under the curve of post-induction systolic blood pressure over time were assessed. Complications associated with pneumatic leg compression were recorded, including: peripheral neuropathy; compartment syndrome; extensive bullae beneath the leg sleeves; and pulmonary thromboembolism. The incidence of post-induction hypotension decreased in the pneumatic leg compression group compared with that in the control group; 5 (10%) vs. 29 (58%), respectively, p < 0.001. In the pneumatic leg compression group, the lowest systolic, diastolic and mean blood pressures 20 min after induction of anaesthesia were significantly greater than the control group. Pneumatic leg compression resulted in an increased area under the curve of systolic blood pressure in the first 20 min after induction, p = 0.001. There were no pneumatic leg compression-related complications. Pneumatic leg compression reduced post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy, suggesting that it is an effective and safe intervention to prevent post-induction hypotension among elderly patients undergoing general anaesthesia.  相似文献   
2.
3.
4.
5.
6.
BackgroundNorepinephrine is as effective as phenylephrine for management of spinal anaesthesia-induced hypotension. Most of the studies comparing these vasopressors have been conducted in healthy pregnant women undergoing elective caesarean section. In the current study, we tested the null hypothesis that there is no difference in neonatal outcome when phenylephrine or norepinephrine is used to treat spinal anaesthesia-induced hypotension in women undergoing emergency caesarean section for fetal compromise.MethodsPatients undergoing caesarean section for fetal compromise who developed spinal anaesthesia-induced hypotension were randomised to receive phenylephrine 100 μg or norepinephrine 8 μg for treatment of each hypotensive episode, defined as systolic blood pressure <100 mmHg. Umbilical cord arterial and venous blood samples were obtained for blood gas analysis. The primary outcome measure was umbilical artery pH.ResultsOne hundred patients (50 in each group) were studied. There was no significant difference in umbilical artery pH between the two groups (mean difference 0.001; 95% CI −0.032 to 0.034). The number of hypotensive episodes, vasopressor boluses required, the incidence of bradycardia, heart rate and blood pressure trends following vasopressor administration, and the incidence of nausea/vomiting were not significantly different between groups.ConclusionPhenylephrine 100 μg and norepinephrine 8 μg were not significantly different in terms of neonatal outcome when administered as intravenous boluses for treatment of spinal anaesthesia-induced hypotension in parturients undergoing emergency caesarean sections for fetal compromise.  相似文献   
7.
BackgroundWe sought to identify independent modifiable risk factors for delayed discharge after total knee arthroplasty (TKA) that have been previously underrepresented in the literature, particularly postoperative opioid use, postoperative laboratory abnormalities, and the frequency of hypotensive events.MethodsData from 1033 patients undergoing TKA for primary osteoarthritis of the knee between June 2012 and August 2014 at an academic orthopedic specialty hospital were reviewed. Patient demographics, comorbidities, inpatient opioid medication, postoperative hypotensive events, and abnormalities in laboratory values, all occurring on postoperative day 0 or 1, were collected. Multivariate logistic regression analysis was performed to identify independent risk factors for a prolonged length of stay (LOS) >3 days.ResultsThe average age of patients undergoing primary TKA in our cohort was 65.9 (standard deviation, 9.1) years, and 61.7% were women. The mean LOS for all patients was 2.64 days (standard deviation, 1.14; range, 1-9). And 15.3% of patients had a LOS >3 days. On multivariate logistic regression analysis, nonmodifiable risk factors associated with a prolonged LOS included nonwhite race (odds ratio [OR], 2.01), single marital status (OR, 1.53), and increasing age (OR, 1.47). Modifiable risk factors included every 5 postoperative hypotensive events (OR, 1.31), 10-mg increases in oral morphine equivalent consumption (OR, 1.04), and postoperative laboratory abnormalities (hypocalcemia: OR, 2.15; low hemoglobin: OR, 2.63).ConclusionThis study identifies potentially modifiable factors that are associated with increased LOS after TKA. Doubling down on efforts to control the narcotic use and to use opioid alternatives when possible will likely have efficacy in reducing LOS. Attempts should be made to correct laboratory abnormalities and to be cognizant of patient opioid use, age, and race when considering potential avenues to reduce LOS.  相似文献   
8.
《中国现代医生》2020,58(27):180-182+187
目的 分析维持性血液透析中引发低血压的因素及相应的护理对策。方法 严格遵循知情与自愿原则从2016年12月~2019年3月就诊于本院并接受维持性血液透析治疗的患者中随机选择50例作为本次研究对象。由医护人员就维持性血液透析中引发低血压的可能性因素进行分析并予以针对性的护理,而后观察记录50例患者的低血压发生率、并发症发生率与生活质量变化情况。结果 50例维持性血液透析患者经针对性护理后的低血压发生率与并发症总发生率分别为6.00%和8.00%,且护理后的各项生活质量指标数据高于护理前,差异均有统计学意义(P0.05)。结论 明确导致维持性血液透析患者在治疗过程中引发低血压的可能性因素,有利于临床对患者采取更具针对性和完善性的护理措施,进而有效预防低血压现象的发生,同时还可在最小化并发症发生率的基础上不断优化其生活质量。  相似文献   
9.
10.
Patent ductus arteriosus is associated with multiple comorbidities in premature infants, however a causal link or strategy to decrease these morbidities has not been found. The association between the patent ductus arteriosus and morbidities has biologic plausibility as, like any cardiac mixing lesion, a significant systemic to pulmonic shunt may lead to pulmonary over-circulation and systemic hypoperfusion. Understanding the underlying pathophysiology of associated morbidities in the setting of a patent ductus arteriosus may aid in risk stratifying infants and offer a patient targeted approach to infants with a pathological ductal shunt. While the deleterious impact of increased pulmonary blood flow maybe easier to identify, the impact on end-organ perfusion is more challenging. In this review, we will discuss the pathophysiology of a hemodynamically significant patent ductus arteriosus in premature infants, impact on end-organ perfusion and associated morbidities, and novel modalities to assess shunt volume and effect on end-organ perfusion.  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