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   767篇
  免费   39篇
  国内免费   8篇
耳鼻咽喉   10篇
儿科学   67篇
妇产科学   26篇
基础医学   69篇
口腔科学   37篇
临床医学   79篇
内科学   182篇
皮肤病学   16篇
神经病学   51篇
特种医学   19篇
外科学   136篇
综合类   19篇
预防医学   28篇
眼科学   13篇
药学   30篇
中国医学   1篇
肿瘤学   31篇
  2024年   1篇
  2023年   2篇
  2022年   9篇
  2021年   15篇
  2020年   10篇
  2019年   18篇
  2018年   29篇
  2017年   14篇
  2016年   11篇
  2015年   24篇
  2014年   28篇
  2013年   53篇
  2012年   47篇
  2011年   51篇
  2010年   40篇
  2009年   40篇
  2008年   60篇
  2007年   74篇
  2006年   81篇
  2005年   63篇
  2004年   47篇
  2003年   29篇
  2002年   27篇
  2001年   2篇
  2000年   4篇
  1999年   5篇
  1998年   3篇
  1997年   4篇
  1995年   2篇
  1994年   1篇
  1993年   3篇
  1992年   1篇
  1991年   1篇
  1990年   3篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1986年   3篇
  1985年   2篇
  1983年   1篇
  1979年   1篇
  1976年   1篇
  1969年   1篇
排序方式: 共有814条查询结果,搜索用时 15 毫秒
61.

Purpose  

The aim of our study was to compare the effects of fentanyl, remifentanil, and dexmedetomidine on neuromuscular blockade under sevoflurane anesthesia.  相似文献   
62.
BackgroundArterial stiffness increases in hypertensive individuals. Arterial stiffness is associated with impairment of systolic and diastolic myocardial function in hypertension (HT). However, the relationship between arterial stiffness and serum heart-type fatty acid-binding protein (H-FABP) levels, a sensitive marker of myocardial damage, has not been previously examined in patients with HT. We investigate the relationship between serum H-FABP levels and arterial stiffness in patients with newly diagnosed HT.MethodsWe studied 46 (48.5 +/- 10.6, years) never-treated patients with HT and age-matched control group of 40 (47 +/- 8.6, years) normotensive individuals. H-FABP levels were determined in all subjects. We evaluated arterial stiffness and wave reflections of study population, using applanation tonometry (Sphygmocor). Carotid-femoral pulse wave velocity (PWV) was measured as indices of elastic-type, aortic stiffness. The heart rate-corrected augmentation index (AIx@75) was estimated as a marker of wave reflections.ResultsCarotid-femoral PWV (10.5 +/- 2.2 vs. 8.7 +/- 1.6, m/s, P = 0.0001) and AIx@75 (22.7 +/- 9.5 vs. 15 +/- 11, %, P = 0.001) were significantly higher in patients with HT than control group. H-FABP levels were increased in hypertensive patients compared with control group (21.1 +/- 14.8 vs. 12.9 +/- 8.5, ng/ml, P = 0.002). In multiple linear regression analysis, we found that the body mass index (beta = 0.42, P = 0.0001) and carotid-femoral PWV (beta = 0.23, P = 0.03) were significant determinants of H-FABP levels.ConclusionArterial stiffness is associated with serum H-FABP levels, a sensitive marker of myocardial damage, in patients with newly diagnosed HT.American Journal of Hypertension (2008). doi 10.1038/ajh.2008.235American Journal of Hypertension (2008); 21, 9, 989-993. doi 10.1038/ajh.2008.235.  相似文献   
63.
Aim: The aim of the study was to evaluate the rate of hepatitis B and C virus infection and emphasize the importance of hepatitis B virus (HBV) vaccination in leukemic children. Methods: One hundred and sixty children who were treated for acute lymphoblastic leukemia (ALL) at Hacettepe University Faculty of Medicine, Pediatric Hematology Unit were included in the study. They were 71 (44.4%) girls and 89 (55.6%) boys with a mean age of 6.45 +/- 3.87 years. Results: Of these 160 children, 22 (13.8%) were anti-HBs-positive and 138 (86.2%) were anti-HBs-negative at the diagnosis of ALL. Among the 138 anti-HBs-negative children, 67 (41.9%) were vaccinated for HBV during maintenance chemotherapy, and 71 (44.3%) could not be vaccinated. Two (2.9%) vaccinated and 22 (30.9%) unvaccinated children developed HBV infection during the follow-up period (P < 0.001). Among 160 children treated for ALL, 24 (15.0%) had HBV, three (1.9%) had hepatitis C virus (HCV) infections, and 29 (18.1%) had toxic hepatitis. The majority of patients with HBV or HCV infections had high risk (HR) protocol, whereas most of the patients with toxic hepatitis had low risk (LR) protocol, especially St Jude Total XIII LR protocol. Conclusion: Viral hepatitis and toxic hepatitis were observed more commonly in the HR and LR group, respectively, of ALL patients. This could be explained by intensive chemotherapy and more heavy blood product administration in the HR group and the chemotherapeutic agents of methotrexate and 6-mercaptopurine, basic drugs used in the LR group. In respect to protection from these complications, periodical liver function tests, serological tests for HBV and HCV, and vaccination for HBV should be performed for all children with ALL.  相似文献   
64.
65.
BACKGROUND: In our study, we assessed the effect of glycoprotein (GP) IIb/IIIa receptor inhibition on microvascular flow after acute coronary occlusion using the early sum of ST segment resolution in electrocardiography. Platelets may play a major role in the dissociation of epicardial artery recanalization and tissue level reperfusion, referred to as the 'no-reflow phenomenon'. Therefore, GP IIb/IIIa receptor inhibition might improve myocardial reperfusion, distinct from its effects on epicardial patency. METHODS AND RESULTS: One hundred and fifteen patients (mean age 57.7 +/- 12.2 years, 96 males, 19 females) with < or = 12-hour acute ST segment elevation myocardial infarction who underwent successful primary percutaneous coronary intervention were retrospectively enrolled into the study. Patients were grouped according to whether they received tirofiban therapy or not. Clinical and electrocardiographic parameters were evaluated. The first sum of ST segment elevation amounts in millimeters was obtained immediately before angioplasty and the second 60 min after restoration of thrombolysis in myocardial infarction III flow. The difference between the two measurements was accepted as resolution of the sum of ST segment elevation and expressed as SigmaSTR. There were no significant differences between the groups regarding age, gender, cardiovascular risk factors, and laboratory parameters, duration from angina onset to the emergency unit, and from door to angioplasty. SigmaSTR was higher in patients who received tirofiban than in those who did not (7.2 +/- 2.8 and 4.2 +/- 2.6 mm, respectively; p < 0.001). There was a significant and positive correlation between GP IIb/IIIa inhibition and SigmaSTR (r = 0.336, p < 0.001), as well as between ejection fraction and SigmaSTR (r = 0.310, p < 0.001). GP IIb/IIIa inhibition was the only independent determinant of SigmaSTR in a multivariate linear regression model which contains 10 variables (p < 0.001). The incidence of in-hospital post-myocardial infarction refractory angina, reinfarction, and heart failure was significantly lower in the tirofiban group (p < 0.05, p < 0.05, and p < 0.05, respectively). Additionally, after 30 days, reinfarction and heart failure were lower in the tirofiban group (p < 0.05 and p < 0.05, respectively). CONCLUSIONS: It is well known that SigmaSTR determines microvascular perfusion. This study shows that GP IIb/IIIa inhibition with tirofiban is of value in preserving microvascular perfusion after restoring coronary thrombolysis in myocardial infarction III flow.  相似文献   
66.
The syndrome of McCune-Albright syndrome (MAS) is clasically defined as a triad presentation with the findings of polyostotic fibrous dysplasia, café-au-lait spots, and sexual precocity. However, not all patients present with complete symptoms. A 52-year-old man was diagnosed as having a variant of McCune-Albright syndrome with the following findings: polyostotic fibrous dysplasia, acromegaly due to pituitary tumor and subclinical hyperthyroidism due to toxic multinodular goiter. Sexual precocity and café-au-lait spots were not noted. Acromegaly was confirmed by laboratory examination (IGF-1, glucose suppression test and TRH stimulation test). Long acting somatostatin analogue was used as treatment. Although the pituitary tumor could not be removed due to technical problems, mass lesions on the cranium were removed subtotally. Histopathological evaluation demonstrated that the lesion complied with fibrous dysplasia. Genomic DNAs were isolated from the craniofacial bones and peripheral leucocytes of the patient. After amplifying the related regions, Gs alpha (Gs alpha) gene was analysed by automatic DNA sequence analysis. An activating mutation of the Gs alpha gene (Arg 201 Cys) was found in the genomic DNA isolated from the bone tissue of the patient, but not in the genomic DNA isolated from the blood. We described a case of MAS associated with Gs alpha mutation in the bone tissue, presenting with polyostotic fibrous dysplasia, subclinical hyperthyroidism and acromegaly.  相似文献   
67.

Aim

To investigate the effects of inspiratory muscle training (IMT) on functional capacity and balance, respiratory and peripheral muscle strength, pulmonary function, dyspnea, fatigue, depression, and quality of life in heart failure patients.

Methods

A prospective, randomized controlled, double-blinded study. Thirty patients with heart failure (NYHA II-III, LVEF<40%) were included. Sixteen patients received IMT at 40% of maximal inspiratory pressure (MIP), and 14 patients received sham therapy (15% of MIP) for 6 weeks. Functional capacity and balance, respiratory muscle strength, quadriceps femoris muscle strength, pulmonary function, dyspnea, fatigue, quality of life, and depression were evaluated.

Results

Functional capacity and balance, respiratory and peripheral muscle strength, dyspnea, depression were significantly improved in the treatment group compared with controls; quality of life and fatigue were similarly improved within groups (p < 0.05). Functional capacity (418.59 ± 123.32 to 478.56 ± 131.58 m, p < 0.001), respiratory (MIP = 62.00 ± 33.57 to 97.13 ± 32.63 cmH2O, p < 0.001) and quadriceps femoris muscle strength (240.91 ± 106.08 to 301.82 ± 111.86 N, p < 0.001), FEV1%, FVC% and PEF%, functional balance (52.73 ± 3.15 to 54.25 ± 2.34, p < 0.001), functional dyspnea (2.27 ± 0.88 to 1.07 ± 0.79, p < 0.001), depression (11.47 ± 7.50 to 3.20 ± 4.09, p < 0.001), quality of life, fatigue (42.73 ± 11.75 to 29.07 ± 13.96, p < 0.001) were significantly improved in the treatment group. Respiratory muscle strength (MIP = 78.64 ± 35.95 to 90.86 ± 30.23 cmH2O, p = 0.001), FVC%, depression (14.36 ± 9.04 to 9.50 ± 10.42, p = 0.011), quality of life and fatigue (42.86 ± 12.67 to 32.93 ± 15.87, p = 0.008) were significantly improved in the control group.

Conclusion

The IMT improves functional capacity and balance, respiratory and peripheral muscle strength; decreases depression and dyspnea perception in patients with heart failure. IMT should be included effectively in pulmonary rehabilitation programs.  相似文献   
68.
The aim of this study was to determine left ventricular (LV) morphology and aortic function in power athletes and to compare them with normal subjects. Thirty-two elite male wrestlers and 15 age-matched healthy male controls were included. All subjects underwent echocardiographic examination. Measurements included LV cavity dimension at systole and diastole, wall thickness, diastolic parameters, and aortic diameter, 3cm above aortic valve, at systole and diastole. Left ventricular mass and mass index were found to be higher in the athletes than in control subjects. The aortic distensibility index was found to be reduced in the athletes compared with controls (2.53 ± 0.91 vs 3.94 ± 1.77cm2dyne–1 10–6, P = 0.003), while the aortic stiffness index was significantly higher in the athletes than in controls (9.12 ± 3.23 vs 6.65 ± 2.35, P = 0.02). However, LV end-systolic wall stress was lower in the athletes than in controls. Furthermore, transmitral early (E) and late (A) peak velocity, peak velocity of the myocardial systolic wave (S m), and early (E m) and atrial (A m) diastolic waves at the inferior wall were higher in the athletes than in controls. Reduced aortic distensibility in elite power athletes may be one of the cardiovascular adaptation factors which affect LV hypertrophy.  相似文献   
69.
The limited efficacy of standard medical therapies for inflammatory bowel diseases has resulted in a continuing search for alternative treatments. Growth hormone (GH) has shown to have mutagenic and proliferative effects on intestinal cells. This study was designed to identify the effect of growth hormone on trinitrobenzene slfonic acid-induced colitis (TNBSIC) in rats. This study was carried out on 30 rats, divided in 3 groups: group 1: TNBSIC+ GH, group 2: TNBSIC, group 3: saline enema. Colitis was induced in male Sprague-Dawley rats (200 g-250 g) by intracolonic installation of 2, 4, 6-trinitrobenzene sulphonic acid in 50% ethanol. GH treatment has been started and continued throughout the study after inducing colitis. All rats were killed after 5 weeks and colonic segments were examined histopathologically. Microscopic and macroscopic damage scores were caulculated. Intestinal damage scores were found higher in Goups II when compared with treatment group (P < 0.05). There was no damage in group 3 as expected. Both macroscopic and microscopic scores were highest in group 2 (P < 0.05). The myloperoxidase activity was found lower comparing to group 2 (P < 0.05). In conclusion, growth hormone replacement had protective effects against colonic inflammation while reducing intestinal damage on TNB-induced colitis.  相似文献   
70.
Trichosporon spp. are emerging as opportunistic agents that cause systemic diseases in immunocompromised hosts. Trichosporonosis carries a poor prognosis in neutropenic patients. Trichosporon japonicum was isolated from the air and named by Sugita et al. Here we present the first case of T. japonicum isolated from a clinical specimen. Two cases of acute myeloid leukemia who had Trichosporon isolates are discussed because of their rarity and growing importance. T. asahii was isolated from the throat, feces and urine of the first patient. T. japonicum was isolated from the sputum of the second patient. Both cases produced high MICs to itraconazole, and low MICs to fluconazole and voriconazole. In virulance factor investigations there was (++) biofilm formation in T. japonicum but not in T. asahii. Conventional mycological studies were not adequate for the identification of the isolate at the species level. In our second case as in the first one, the isolate was identified as T. asahii with 99.9% accuracy by API 20C AUX. Although two T. asahii isolates from the same patient yielded identical typing profiles by arbitrary primed-PCR, the isolates of the two different patients showed different arbitrary primed-PCR typing profiles. However, the genetic identification of the other patient's strain gave the result of T. japonicum.  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