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   413篇
  免费   24篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   1篇
妇产科学   2篇
基础医学   69篇
临床医学   32篇
内科学   125篇
神经病学   27篇
外科学   32篇
预防医学   11篇
药学   96篇
中国医学   1篇
肿瘤学   42篇
  2022年   2篇
  2021年   4篇
  2020年   4篇
  2019年   3篇
  2018年   8篇
  2017年   10篇
  2016年   3篇
  2015年   10篇
  2014年   5篇
  2013年   17篇
  2012年   20篇
  2011年   16篇
  2010年   16篇
  2009年   12篇
  2008年   24篇
  2007年   20篇
  2006年   19篇
  2005年   18篇
  2004年   23篇
  2003年   21篇
  2002年   25篇
  2001年   13篇
  2000年   12篇
  1999年   9篇
  1998年   3篇
  1997年   8篇
  1996年   3篇
  1995年   5篇
  1994年   2篇
  1993年   3篇
  1992年   15篇
  1991年   11篇
  1990年   12篇
  1989年   11篇
  1988年   7篇
  1987年   2篇
  1986年   7篇
  1985年   14篇
  1984年   3篇
  1983年   7篇
  1982年   3篇
  1981年   2篇
  1977年   1篇
  1976年   1篇
  1974年   1篇
  1973年   1篇
  1971年   1篇
  1969年   1篇
  1968年   2篇
排序方式: 共有440条查询结果,搜索用时 31 毫秒
1.
2.
We aimed to explore whether the acute bronchodilation induced by indacaterol 150 μg and glycopyrronium bromide 50 μg is additive or synergistic with respect to monocomponents by testing the type of effect ex vivo on isolated human bronchi and then in vivo in COPD patients. Both indacaterol and glycopyrronium caused a concentration-dependent relaxation of human isolated bronchial tissues sub-maximally pre-contracted with acetylcholine; glycopyrronium was significantly more potent than indacaterol. The analysis of data using the Bliss Independence (BI) criterion indicated that glycopyrronium plus indacaterol produced an additive interaction at the isoeffective concentrations inducing EC20 and a significant synergistic relaxant effect at isoeffective concentrations inducing EC30. In COPD patients, the inhalation of indacaterol and glycopyrronium in combination significantly anticipated at 15 min post-administration the mean peak of bronchodilatory effect compared to the two drugs administered alone. The study of interaction between indacaterol and glycopyrronium by BI analysis evidenced an additive effect for FEV1 between 5 min and 180 min post-inhalation, with synergistic interaction at 15 min post-administration, compared to the bronchodilation induced by these drugs administered alone. This study suggests that the combination ensures a broncholytic effect that is greater than that induced by the single monocomponents.  相似文献   
3.
4.
Because many antihypertensive drugs can affect airway function, the treatment of hypertension in patients with airway dysfunction is complex. For example, the worsening or precipitation of asthma by beta-adrenoceptor antagonists is well-recognized, but beta(1)-adrenoceptor blockers that exert mild beta(2)-agonist effects, and those that modulate the endogenous production of nitric oxide, affect airway function to a lesser extent. Therapy with selective alpha(1)-blockers is not contraindicated in cases of chronic airway obstruction. Conversely, alpha(2)-agonists must not be given to asthmatic subjects because they can adversely affect the bronchi. Calcium channel blockers do not exert severe side effects on the airways. Angiotensin-converting enzyme inhibitors may cause cough and exacerbate or even induce asthma; however, angiotensin II type I (AT(1)) antagonists do not cause cough. 5-Hydroxytryptamine modifiers such as urapidil are a treatment option for patients with chronic airway obstruction. In patients with airway dysfunction, we suggest treatment with thiazide diuretics as the initial drug choice, and calcium channel blockers if the response is poor. In the case of no response, calcium channel blockers alone must be used. However, there is no strict rule because individual patients may respond differently to individual drugs and drug combinations. Consequently, it is important to adopt a flexible approach. For patients who are unresponsive to the aforementioned drugs, AT(1) receptor antagonists, newer beta(1)-adrenoceptor-blocking agents with ancillary properties (eg, celiprolol or nebivolol), and/or vasodilators can be considered.  相似文献   
5.
AIM:To evaluate the prevalence of Giardia lamblia(G.lamblia)infection in patients with irritable bowel syndrome(IBS)and dyspepsia and to establish which is the mostaccurate test to diagnose the infection in this setting.METHODS:One hundred and thirty-seven patients whoconsecutively attended the Outpatient GastroenterologyClinic for the first time between January 2002 and De-cember 2003 due to symptoms of IBS and/or dyspepsiawere recruited.All patients underwent clinical evaluation,first-step haematology and chemistry tests,serologic as-says for celiac disease,lactose-H2 breath test,abdominalultrasonography,and esophagogastroduodenoscopy.Helicobacter pylori status was evaluated.In patients withsymptoms of IBS older than 45 years,colonoscopy wasalso performed.In all patients,duodenal biopsies andstool samples were examined for trophozoites and cystsof G.lamblia by several methods.RESULTS:G.lamblia was identified in 9 patients.Thefollowing diagnoses were also made:IBS(100/137,73%),functional dyspepsia(62/137,45%),organicdyspepsia(33/137,24%),and lactose intolerance(75/137,55%).A significant association was foundbetween giardiasis and H pylori infection(X~2=6.632,OR=12.4,CI=1.5-68.1).There were no symptomsthat reliably allowed the recognition of giardiasis.Direct search of the parasite in duodenal biopsy andstool sample examinations gave concordant results inall cases while histological examination of duodenal biopsies displayed a low sensitivity(e.g.,22.2%).CONCLUSION:In this consecutive series,diagnosisof G.lamblia infection accounted for 6.5% of patientswith IBS and dyspepsia.Duodenal biopsies for diag-nosis of giardiasis may be unnecessary if stool sampleexamination is performed.  相似文献   
6.
7.
Introduction: Inhaled corticosteroids are the only drugs that effectively suppress the airway inflammation, but they can induce considerable systemic and adverse effects when they are administered chronically at high doses. Consequently, the pharmaceutical industry is still searching for newer entities with an improved therapeutic index.

Areas covered: Herein, the authors review the research in the glucocorticoid field to identify ligands of the glucocorticoid receptor (GR). These ligands preferentially induce transrepression with little or no transactivating activity, in order to have a potent anti-inflammatory action and a low side-effects profile.

Expert opinion: Several agents have been synthesized, but few have been tested in experimental models of asthma. Furthermore, only three (BI-54903, GW870086X and AZD5423) have entered clinical development, although the development of at least one of them (BI-54903) was discontinued. The reason for the limited success so far obtained is that the model of transactivation versus transrepression is a too simplistic representation of GR activity. It is difficult to uncouple the therapeutic and harmful effects mediated by GR, but some useful information that might change the current perspective is appearing in the literature. The generation of gene expression ‘fingerprints’ produced by different GR agonists in target and off-target human tissues could be useful in identifying drug candidates with an improved therapeutic ratio.  相似文献   

8.
Despite abundant epidemiological data linking metals to leukemia and other cancers, baseline values of toxic and essential metals in patients with leukemia and the clinical impact of these metals remain unknown. Thus, we sought to quantify metal values in untreated patients with acute myeloid leukemia (AML) and controls and determine the impact of metal values on AML patients' survival. Serum samples from patients with untreated AML and controls at Hospices Civils de Lyon were analyzed and compared for trace metals and copper isotopic abundance ratios with inductively coupled plasma mass spectrometry. Survival analysis was performed as a function of metal values, and a multi-metal score was developed for patients with AML. Serum samples were collected from 67 patients with untreated AML and 94 controls. Most patients had intermediate-risk cytogenetics (63.1%) without FLT3 internal tandem duplication mutations (75.6%) or NPM1 mutations (68.1%). Most metal values differed significantly between AML and control groups. Patients with lower magnesium and higher cadmium values had the worst survival rates, with only 36% surviving at 6 months (P = .001). The adverse prognostic effect of this combination was maintained on multivariate analysis. Based on this, we developed a novel metal score, which accounts for multiple relative abnormalities in the values of five toxic and five essential metals. Patients with a higher metal score had significantly worse survival, which was maintained on multivariate analysis (P = .03). This baseline metal scoring system was also prognostic when we applied it to a separate population of front-line AML patients.  相似文献   
9.
The aim of this double-blind, double-dummy, crossover, randomised, pilot study was to explore the acute effects of adding salmeterol and tiotropium in patients with stable COPD. A total of 20 outpatients with stable COPD were enrolled. Single doses of 18-microg tiotropium, 50-microg salmeterol, and 18-microg tiotropium+ 50-microg salmeterol were given. Serial measurements of forced expiratory volume in 1 s (FEV1) were performed over 24h. The mean maximum increases in FEV1 from pre-dosing value on each of the dosing days were 0.165l (95% CI: 0.098-0.232) for tiotropium, 0.241 l (95% CI: 0.151-0.332) for salmeterol, and 0.290 l (95% CI: 0.228-0.353) for the combination and occurred 4 h after inhalation of tiotropium or salmeterol and 3 h after the combination. At 12h, the mean increases in FEV1 from pre-dosing value were 0.071 l (95% CI: 0.001-0.141; P = 0.047) for tiotropium, 0.069 l (95% CI: 0.018-0.120; P = 0.010) for salmeterol, and 0.108 l (95% CI: 0.047-0.170; P = 0.001) for the tiotropium + salmeterol combination. Only the difference between salmeterol and tiotropium + salmeterol was statistically significant (P = 0.009). At 24h, the mean FEV1 value was still higher than the mean pre-dosing value for tiotropium (0.042 l; 95% CI: -0.012-0.097; P=0.119) and the tiotropium+salmeterol combination (0.051 l; 95% CI: 0.01 5-0.087; P = 0.007), but not for salmeterol alone (-0.013 l; 95% CI: -0.041-0.014; P = 0.324). The FEV1 area under the curve (AUCs0-12h) were 1.657 l (95% CI: 1.152-2.162) for tiotropium, 2.068 (95l CI: 1.385-2.752) for salmeterol, and 2.541 l (95% CI: 1.954-3.129) for tiotropium + salmeterol. Only the difference between tiotropium and the tiotropium +salmeterol combination was statistically significant (P = 0.01). The FEV1 AUCs0-24h were 2.854 l (95% CI: 1.928-3.780) for tiotropium, 2.786 l (95% CI: 1.913-3.660) for salmeterol, and 3.640 l (95% CI: 2.674-4.605) for tiotropium + salmeterol. ALL differences between treatments were not statistically significant (P> 0.05). These results seem to indicate that the use of the tiotropium + salmeterol combination is more efficacious than the single agents alone, but the once-daily administration of the two drugs is inadvisable due to the broncholytic profile of salmeterol.  相似文献   
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