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   1374篇
  免费   47篇
  国内免费   7篇
儿科学   27篇
妇产科学   5篇
基础医学   81篇
口腔科学   1篇
临床医学   352篇
内科学   245篇
皮肤病学   10篇
神经病学   10篇
特种医学   45篇
外科学   208篇
综合类   232篇
预防医学   70篇
药学   105篇
中国医学   30篇
肿瘤学   7篇
  2024年   5篇
  2023年   27篇
  2022年   47篇
  2021年   86篇
  2020年   45篇
  2019年   35篇
  2018年   38篇
  2017年   22篇
  2016年   30篇
  2015年   23篇
  2014年   67篇
  2013年   66篇
  2012年   53篇
  2011年   72篇
  2010年   60篇
  2009年   85篇
  2008年   61篇
  2007年   65篇
  2006年   59篇
  2005年   53篇
  2004年   50篇
  2003年   56篇
  2002年   42篇
  2001年   32篇
  2000年   27篇
  1999年   29篇
  1998年   29篇
  1997年   25篇
  1996年   21篇
  1995年   11篇
  1994年   10篇
  1993年   12篇
  1992年   11篇
  1991年   9篇
  1990年   11篇
  1989年   8篇
  1988年   6篇
  1987年   8篇
  1986年   6篇
  1985年   14篇
  1984年   3篇
  1983年   3篇
  1982年   1篇
  1981年   1篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
排序方式: 共有1428条查询结果,搜索用时 281 毫秒
1.
目的探讨油酸性急性呼吸窘迫综合征(ARDS)beagle犬血浆及肺泡灌洗液血管内皮生长因子(VEGF)、可溶性细胞间黏附分子-1(ICAM-1)、白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF—α)水平的改变。方法12只英国纯种beagle犬,静脉注射油酸0.15mL/kg,在注射油酸前、后1h,出现ARDS的典型表现时,抽血测VEGF、sICAM-1、IL-8、TNF—α,并对此时相作肺泡灌洗液VEGF、sICAM—1、IL-8、TNF-α的测定。结果beagle犬静脉注射油酸后1h血浆TNF—α升高(P〈0.05),血浆反肺泡灌洗液IL8、sICAM-1和VEGF在1h较油酸前没有明显变化(P〉0.05),beagle犬油酸型ARDS模型建立后血浆及肺泡灌洗液VECF、sICAM-1、IL-8、TNF—α均显著高于建模前(P〈0.05)。结论VEGF、sICAM-1、IL-8、TNF~α在beagle犬油酸型ARDS发生发展过程中可能均起重要作用,其水平的高低可能与ARDS严重程度及预后有关。  相似文献   
2.
泵式自体输血过滤引流系统在急症救护中的应用   总被引:5,自引:1,他引:4  
自体输血、胸腔闭式引流,是缓解血源矛盾、赢得抢救时机、防治心肺衰竭及ARDS/MOF的重要措施。笔者研制成功的手控泵式储血过滤引流系列在战地、灾害现场,以及平时的心肺手术中,共应用3000余例,现重点对其功能设计和用于自体输血、紧急救护做讨论和评估。  相似文献   
3.
Objective: To determine whether the quality of infiltrations in chest radiographs can accurately predict the histological extent of fibrotic change in patients with acute respiratory distress syndrome (ARDS). Design: Retrospective clinical investigation. Setting: Intensive care unit (ICU) of a university teaching hospital. Patients and methods: Of 47 patients treated with extracorporeal membrane oxygenation (ECMO) for severe ARDS over a 5-year period, 23 patients underwent open lung biopsy at thoracotomy for treatment, mostly of pneumothorax. Chest films obtained by portable chest roentgenography preceding the operation were reviewed retrospectively and compared to the histomorphological results of the lung specimen. Results: Chest radiographs displayed mixed alveolar-reticular opacification in 60.2 %, alveolar patterns in 22.9 % and reticular opacities in 10.5 %. In 0.4 % there were no infiltrates, 6 % could not be evaluated because of insufficient quality. There was no relevant difference between the right and left lungs. Subdividing patients into two groups according to the histological results of either absent or mild (1) or severe (2) lung fibrosis, we found an alveolar haziness in 12.3 % in group 1 compared with 28.2 % in group 2, while reticular characteristics were identified in 13 % and 11 %, respectively. Conclusions: The most common opacity in chest radiographs of patients with severe ARDS treated with ECMO is mixed alveolar-reticular opacification. Severe lung fibrosis is not positively correlated with a reticular radiographic pattern. ECMO does not lead to specific radiological changes in conventional radiograms, contrary to clinical findings that treatment with ECMO might induce pleural or pulmonic haemorrhage, especially in the earlier days when systemic heparinization had to be used instead of the heparin-coated tube-surfacing. Received: 24 November 1997 Accepted: 20 July 1998  相似文献   
4.
控制性肺膨胀在食管癌术后应用的临床对比研究   总被引:1,自引:0,他引:1  
肖凌  郭川 《重庆医学》2003,32(10):1372-1373
目的 观察在食管癌术后应用控制性肺膨胀防止急性呼吸衰竭的疗效。方法 随机设立应用控制性肺膨胀组 4 3例和对照组 33例 ,年龄和手术时间等无显著差异。观察撤离呼吸机时间。撤机后 1 2、2 4h的呼吸频率、心率、血氧饱和度和氧分压。结果  (1 )应用控制性肺膨胀后 ,撤机时间由 (1 0 4± 1 5 )min缩短到 (87± 1 3)min。 (2 )撤机后 1 2h ,控制性肺膨胀组血氧饱和度和氧分压异常的患者率分别由 30 .30 %下降到 6 .98% ,2 4 .2 4 %下降到 6 .98%。 (3)撤机后 2 4h ,血氧饱和度异常的患者率由1 8.1 8%下降到 2 .33%。结论 食管癌术后应用控制性肺膨胀能有效防止急性呼吸衰竭的发生。  相似文献   
5.
INTRODUCTIONAdultRespiratoryDistressSyndrome(ARDS)isanacuteprogressiverespiratoryfailurecausedbymanyreasons.Thetherapeuticactionofthissyndromeisuncertain,becausethemechanismisnotwellknown.Thatis,theprognosisiscritical,themortailityisquiteheigh(50%f)ti--63'Butintherecenttenyears,manyscholarsinourcountryhavehadmuchexperienceintheaspectofusinganisodaminetorescueARDSpatientsandhavedecreasedthemortality(')'Howeveverthescholarsexplaintheprincipleofitindifferentways'Thechangesofmicrovascula…  相似文献   
6.
We develop tidal-ventilation pulmonary gas-exchange equations that allow pulmonary shunt to have different values during expiration and inspiration, in accordance with lung collapse and recruitment during lung dysfunction (Am. J. Respir. Crit. Care Med. 158 (1998) 1636). Their solutions are tested against published animal data from intravascular oxygen tension and saturation sensors. These equations provide one explanation for (i) observed physiological phenomena, such as within-breath fluctuations in arterial oxygen saturation and blood-gas tension; and (ii) conventional (time averaged) blood-gas sample oxygen tensions. We suggest that tidal-ventilation models are needed to describe within-breath fluctuations in arterial oxygen saturation and blood-gas tension in acute respiratory distress syndrome (ARDS) subjects. Both the amplitude of these oxygen saturation and tension fluctuations, and the mean oxygen blood-gas values, are affected by physiological variables such as inspired oxygen concentration, lung volume, and the inspiratory:expiratory (I:E) ratio, as well as by changes in pulmonary shunt during the respiratory cycle.  相似文献   
7.
Summary The past decades have seen considerable shifts of emphasis in surgical care. The recognition that pus was not laudable, was followed by a realisation that not all complications were inevitable and that prophylaxis could effectively reduce the incidence of most common problems in the post-operative period. As anaesthesia has become safer, it has been possible to embark on more intricate and prolonged procedures and for sufficient time to be available to ensure adequate intraoperative care.These two phenomena have firstly increased the complexity of management in the post-operative period, and have brought this aspect of surgical care more obviously to the limelight. However, many separate disciplines are involved in the care of the patient post-operatively, and the Symposium was organised1 to bring the different groups together to identify the areas of recent development in the different specialities and to integrate the overall care of the individual patient.Abbreviations ARDS adult respiratory distress syndrome - DIC disseminated intravascular clotting  相似文献   
8.
Zusammenfassung Nach multiplem Trauma sinken intracelluläre Aktivität und Konzentration der Elastase in polymorphkernigen Leukocyten (PMNL), die aus Blut ( = 67 U und 6154 g/109 PMNL) und bronchoalveolärer Lavage (BAL)-Flüssigkeit ( = 44 U und 5957 g/109 PMNL) isoliert wurden im Vergleich zu PMNL Gesunder ( = 106 U und 9962 g/109 PMNL). Gleichzeitig wurde ein Anstieg der extracellulären Elastase-Konzentration in Plasma von = 84 g/1 auf = 399 g/1 und in BAL Flüssigkeit von = 8 g/1 auf = 561 g/1 beobachtet. Die durch Stimulation freigesetzte Elastase wird teilweise von einem spezifischen Receptor auf PMNL erneut gebunden. Die Ergebnisse unterstützen die PMNL-vermittelte ARDS-Pathogenese.  相似文献   
9.
Limited information is available on the clinical course of outpatients with mild coronavirus disease (COVID-19). This information is critically important to inform public health prevention strategies and to provide anticipatory guidance to patients, primary care providers, and employers. We retrospectively assessed the daily prevalence of symptoms in 313 COVID-19 outpatients for the first 20 days of illness. Generalized estimating equations were used to assess the probability of symptom occurrence over time. Fatigue (91%), cough (85%), and headache (78%) were the most common symptoms and occurred a median of 1 day from symptom onset. Neurologic symptoms, such as loss of taste (66%) and anosmia (62%), and dyspnea (51%) occurred considerably later (median 3–4 days after symptom onset). Symptoms of COVID-19 are similar to those of other respiratory pathogens, so symptomatic patients should be tested more frequently for severe acute respiratory syndrome coronavirus 2 during influenza season to prevent further spread of COVID-19.  相似文献   
10.
目的 探讨肾综合征出血热 (HFRS)并发急性呼吸窘迫综合征 (ARDS)临床特征及诊断和抢救措施。方法 对 8例HFRS并发ADRS临床特征及血气、X检查进行分析诊断及其抢救措施。结果  8例中 3例治愈(早期 2例 ,中期 1例 )。 5例死亡 (皆为中晚期 )。治愈率为 37 5% (3/ 8) ;病死率 6 2 5% (5/ 8)。结论 ARDS发病期别与预后关系较大。其发病机理主要是各种致病因素 ,尤其是严重感染和休克 ,使体内产生大量炎性介质、可使毛细血管扩张 ,通透性增加 ,引起间质性肺水肿。由于中性粒细胞和血小板被活化 ,可释放大量自由基 ,使肺微血管损伤和通透性增加 ,使肺含水量增高所致。救治措施 ,积极治疗和纠正原发病 ,迅速纠正缺氧 ,限制液体入量 ,早期使用胶体液 ,减轻肺水肿。早期大量肾上腺皮质激素应用 ;α受体阻滞剂 -酚氨拉明及抗胆碱能药物 -东莨菪碱应用 ,均对改善肺水肿有益。  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