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   42254篇
  免费   2678篇
  国内免费   914篇
耳鼻咽喉   355篇
儿科学   1035篇
妇产科学   341篇
基础医学   3314篇
口腔科学   421篇
临床医学   6135篇
内科学   8718篇
皮肤病学   192篇
神经病学   2477篇
特种医学   1233篇
外国民族医学   2篇
外科学   4973篇
综合类   5922篇
现状与发展   3篇
预防医学   2477篇
眼科学   2487篇
药学   4369篇
  26篇
中国医学   1188篇
肿瘤学   178篇
  2024年   52篇
  2023年   677篇
  2022年   932篇
  2021年   1735篇
  2020年   1569篇
  2019年   1380篇
  2018年   1451篇
  2017年   1336篇
  2016年   1327篇
  2015年   1257篇
  2014年   2726篇
  2013年   3148篇
  2012年   2165篇
  2011年   2483篇
  2010年   1828篇
  2009年   1837篇
  2008年   1958篇
  2007年   1940篇
  2006年   1746篇
  2005年   1457篇
  2004年   1271篇
  2003年   1028篇
  2002年   912篇
  2001年   877篇
  2000年   690篇
  1999年   643篇
  1998年   567篇
  1997年   594篇
  1996年   498篇
  1995年   544篇
  1994年   474篇
  1993年   422篇
  1992年   429篇
  1991年   382篇
  1990年   358篇
  1989年   309篇
  1988年   323篇
  1987年   294篇
  1986年   265篇
  1985年   299篇
  1984年   306篇
  1983年   178篇
  1982年   242篇
  1981年   197篇
  1980年   174篇
  1979年   150篇
  1978年   133篇
  1977年   76篇
  1976年   67篇
  1975年   45篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
31.
32.
《Cor et vasa》2015,57(3):e157-e162
IntroductionObstructive sleep apnea (OSA) is often connected with arterial hypertension and it could also be a cause of secondary hypertension. Treatment of arterial hypertension and optimal blood pressure level are important for prevention of cardiovascular complications. It is not well known how to treat patients with OSA and arterial hypertension. Also many patients with OSA suffer from metabolic syndrome which worsen their prognosis.AimThe aim of our study was to assess arterial hypertension compensation in patients with metabolic syndrome and moderate to severe OSA and to analyze used pharmacotherapy.Materials and methods85 hypertensive patients (75 men) with metabolic syndrome, average age 53.6 ± 9.3 years, were evaluated using overnight sleep study with diagnosis of OSA, average apnea–hypopnea index (AHI) 56.3 ± 23. Patients underwent 24 h ambulatory blood pressure monitoring (ABPM) and their current pharmacotherapy data were obtained. Appropriate combinations of antihypertensive drugs (patients with metabolic syndrome) were derived from ESH/ESC 2013 guidelines.ResultsArterial hypertension was well compensated in only 11.8% of the patients. 24.7% patients were treated according to current guidelines. Fisher's exact test with analysis of adjusted residues has found higher rate of blood pressure subcompensation in patients treated with triple+ combination of drugs (p = 0.035, 51.4% vs 10%).ConclusionOnly a small number of patients had optimal blood pressure level and were treated according to current ESH/ESC guidelines. We have to constantly appeal to all physicians to perform ABPM in patients with OSA.  相似文献   
33.
目的检测阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者中血清血管紧张素转换酶(ACE)水平的变化及其临床意义。方法设置OSAHS组(n=40)和健康对照组(n=40),测定并比较患者的血压、血脂和血清ACE水平在两组间的差异;分析ACE水平与患者病情变化、血压、血脂的相关性。结果 OSAHS患者在体重、BMI指数、颈围、腰围、AHI、收缩压、舒张压、TC、LDL-C和血清ACE方面高于健康人(P体重=0.002,P颈围=0.024,P腰围=0.038,PBMI=0.019,PAHI=0.001,P收缩压=0.001,P舒张压=0.001,PTC=0.017,PLDL-C=0.010,PACE=0.039),在LSa O2上低于健康人(PLSa O2=0.001)。OSAHS患者的收缩压、TC、ACE在轻中度和中重度之间均存在统计学差异(P收缩压=0.018、0.043,PTC=0.045、0.034,PACE=0.030、0.001),相关性分析显示,OSAHS患者中血清ACE与收缩压和TC均呈正相关(r=0.35,P=0.017;r=0.28,P=0.044)。结论 OSAHS患者血清ACE能反映患者病情的变化,并与血压和血脂具有一定相关性。  相似文献   
34.
35.
目的:分析鼻塞式同步间歇正压通气(NIPPV)联合布地奈德雾化治疗ARDS(新生儿急性呼吸窘迫综合征)疾病的临床应用效果。方法:纳入病例是2017年5月—2019年11月收治的104例ARDS新生儿,随机平均分为两组。参照组52例采纳CPAP(持续气道正压通气通气)治疗,实验组52例采纳NIPPV+布地奈德雾化治疗,对比两组呼吸机通气时间、用氧时间、住院时间、血气指标以及并发症发生情况。结果:实验组呼吸机通气时间、用氧时间、住院时间均明显短于参照组,差异有统计学意义P<0.05;实验组治疗3 d后PaCO2明显低于参照组,实验组治疗3 d后PH以及PaO2明显高于参照组,差异有统计学意义P<0.05;实验组并发症发生率(3.85%,2/52)明显低于参照组(21.15%,11/52),差异有统计学意义P<0.05。结论:NIPPV+布地奈德雾化可有效缩短ARDS患者机械通气时间,改善血气指标,降低并发症发生率,值得借鉴。  相似文献   
36.
目的探讨工作坊模式在护生压疮护理带教中的应用效果,为临床护理带教提供参考。方法选取2018年7月—2019年6月在医院实习的120名护生作为研究对象,随机分为对照组和观察组,各60名护生。对照组采用传统带教法进行压疮培训,观察组采用工作坊教学模式进行培训。培训结束后比较两组护生压疮知识的掌握程度即理论考核、技能操作成绩,教学效果满意度。结果观察组护生对压疮知识的掌握程度即理论考核成绩、技能操作考核成绩远远高于对照组,两组差异具有统计学意义(P<0.05)。95%的观察组护生对工作坊教学模式的效果表示满意,认为工作坊教学模式能够提高学习的兴趣、主动性和临床实践能力,对临床工作有很大帮助。结论工作坊教学模式应用于压疮护理的临床带教,能让护生亲身体验压疮护理的过程,并参与其中,将理论与实践相结合,更好地活跃课堂气氛,启发护生思考,提高护生对压疮理论和技能的掌握,为临床实际工作中压疮护理质量的提高奠定基础。  相似文献   
37.
38.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
39.
李红霞  李晓燕 《中国校医》2019,33(7):517-518
目的 观察高通量血液透析(HFHD)与低通量血液透析(LFHD)的不同模式运用到老年患者维持性血液透析(MHD)中对其血压的影响。方法 选择2015年2月—2017年10月本院治疗的MHD老年患者74例,先为其施LFHD 3个月,再为其辅以3个月的HFHD,3次/周,4 h/次,对比不同透析模式对患者血压的影响。结果 实施HFHD后患者的平均动脉压(MAP)有所降低,在第3 h与第4 h透析后,血压把控优于LFHD(P<0.05)。结论 对于MHD老年患者来说,实施HFHD是优良的透析方法。  相似文献   
40.

Background

Etomidate is frequently selected over propofol for induction of anaesthesia because of a putatively favourable haemodynamic profile, but data confirming this perception are limited.

Methods

Patients undergoing cardiac surgery were randomised to induction of anaesthesia with propofol or etomidate. Phase I (n=75) was conducted as open-label, whereas Phase II (n=75) was double blind. Mean arterial blood pressure (MAP) and boluses of vasopressor administered after induction were recorded. The primary endpoint was the area under the curve below baseline MAP (MAP-time integral) during the 10 min after induction. Secondary endpoints were the use of vasopressors over the same period, and the effect of blinding on the aforementioned endpoints. Groups were compared using regression models with phase and anaesthetist as factors.

Results

The mean difference between etomidate and propofol in the MAP-time integral below baseline was 2244 mm Hg s (95% confidence interval, 581–3906; P=0.009), representing a 34% greater reduction with propofol. Overall, vasopressors were used in 10/75 patients in the etomidate group vs 21/75 in the propofol group (P=0.38), and in 20/74 patients during the blinded phase vs 11/76 during the open-label phase (P=0.31). The interaction between randomisation and phase (open-labelled or blinded) was not significant for either primary (P=0.73) or secondary endpoints (P=0.90).

Conclusions

Propofol caused a 34% greater reduction in MAP-time integral from baseline after induction of anaesthesia than etomidate, despite more frequent use of vasopressors with propofol, confirming the superior haemodynamic profile of etomidate in this context. The proportion of patients receiving vasopressors increased slightly, albeit not significantly, in both groups in the blinded phase.

Clinical trial registration

Australian and New Zealand Clinical Trials Registry, ACTRN12614000717651.  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