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   942篇
  免费   42篇
  国内免费   19篇
耳鼻咽喉   19篇
儿科学   40篇
妇产科学   28篇
基础医学   62篇
口腔科学   33篇
临床医学   83篇
内科学   227篇
皮肤病学   16篇
神经病学   67篇
特种医学   27篇
外科学   174篇
综合类   32篇
预防医学   34篇
眼科学   45篇
药学   87篇
中国医学   9篇
肿瘤学   20篇
  2024年   2篇
  2023年   10篇
  2022年   28篇
  2021年   26篇
  2020年   16篇
  2019年   18篇
  2018年   23篇
  2017年   22篇
  2016年   19篇
  2015年   34篇
  2014年   37篇
  2013年   58篇
  2012年   80篇
  2011年   74篇
  2010年   41篇
  2009年   39篇
  2008年   73篇
  2007年   90篇
  2006年   67篇
  2005年   67篇
  2004年   50篇
  2003年   47篇
  2002年   26篇
  2001年   17篇
  2000年   7篇
  1999年   7篇
  1998年   7篇
  1997年   3篇
  1996年   1篇
  1995年   4篇
  1994年   4篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1989年   1篇
  1988年   1篇
  1982年   1篇
排序方式: 共有1003条查询结果,搜索用时 15 毫秒
11.
Background:Chronic kidney disease (CKD)-associated pruritus (CKD-aP) contributes to poor quality of life, including reduced sleep quality and poor sleep quality is a source of patient stress and is linked to lower health-related quality of life. This study aimed to investigate the effectiveness of zolpidem 10 mg and acupressure therapy on foot acupoints to improve the sleep quality and overall quality of life among hemodialysis patients suffering from CKD-aP.Method:A multicenter, prospective, randomized, parallel-design, open label interventional study to estimate the effectiveness of zolpidem (10 mg) oral tablets versus acupressure on sleep quality and quality of life in patients with CKD-aP on hemodialysis. A total of 58 hemodialysis patients having sleep disturbance due to CKD-aP completed the entire 8-week follow-up. The patients were divided into a control (acupressure) group of 28 patients and an intervention (zolpidem) group of 30 patients.Results:A total of 58 patients having CKD-aP and sleep disturbance were recruited. In the control group there was a reduction in the PSQI score with a mean ± SD from 12.28 ± 3.59 to 9.25 ± 3.99, while in the intervention group the reduction in PSQI score with a mean ± SD was from 14.73 ± 4.14 to 10.03 ± 4.04 from baseline to endpoint. However, the EQ5D index score and EQ-visual analogue scale (VAS) at baseline for the control group with a mean ± SD was 0.49 ± 0.30 and 50.17 ± 8.65, respectively, while for the intervention group the values were 0.62 ± 0.26 and 47.17 ± 5.82, respectively. The mean EQ5D index score in the control group improved from 0.49 ± 0.30 to 0.53 ± 0.30, but in the intervention group there was no statistical improvement in mean EQ5D index score from 0.62 ± 0.26 to 0.62 ± 0.27 from baseline to week 8. The EQ 5D improved in both groups and the EQ-VAS score was 2.67 points higher at week 8 as compared to baseline in the control group, while in the intervention group the score was 3.33 points higher at week 8 as compared to baseline. Comparing with baseline, the PSQI scores were significantly reduced after week 4 and week 8 (P =  < .001). Furthermore, at the end of the study, the PSQI scores were significantly higher in the control as compared to the intervention group (P = .012).Conclusion:An improvement in sleep quality and quality of life among CKD-aP patients on hemodialysis has been observed in both the control and intervention groups. Zolpidem and acupressure safety profiling showed no severe adverse effect other that drowsiness, nausea and daytime sleeping already reported in literature of zolpidem.  相似文献   
12.
Objective: The purpose of this study was to examine the vasoreactivity in retina and choroid of the healthy eyes in response to experimentally altered partial arterial pressure of carbon dioxide (PaCO2) using a non-invasive technique, spectral domain optical coherence tomography (SD-OCT).

Materials and methods: The study included non-smoking participants between 18 and 35 years of age, having visual acuity of 20/20 and with no systemic and ocular diseases. At baseline, the participants breathed room air (normocapnia). Hypocapnia was created with the help of hyperventilation; for this, the participants were instructed to draw deep and quick breaths, resulting one breathing cycle per 2?s. To create hypercapnia subjects rebreathed from a 5?l bag at least 3?min. Choroidal thickness and retinal artery diameter were measured at baseline, and hyperventilation and rebreathing conditions by SD-OCT.

Results: Twenty eyes of 20 healthy subjects were included in this study. Their mean age was 24.90?±?5.32 years. Hyperventilation caused a significant reduction in choroidal thickness, compared with baseline, at all points; whereas rebreathing caused no significant change at all points. The mean diameters of the arteries were 151.80?±?7.88?μm, with a significant decline to 148.90?±?7.25?μm at hyperventilation condition and a significant increase to 153.50?±?7.88?μm at rebreathing condition (p?=?0.018, p?=?0.043, respectively).

Conclusion: This study demonstrated that, SD-OCT was a useful tool in measuring the ocular vascular response under hypercapnia and hypocapnia conditions. These findings may be helpful for further understanding the physiological nature of ocular blood flow and this preliminary study provides a basis for future studies.  相似文献   
13.

Background:

Although it is well described among adults, intravenous colistin use and its associated toxicities in newborns are poorly understood.

Objectives:

We present our experience of efficacy and safety of intravenous colistin in the treatment of sepsis in term and preterm neonates.

Patients and Methods:

The records of neonates who received colistin between January 2013 and February 2014 were retrospectively reviewed. All neonates with culture proven nosocomial infections due to multidrug resistant organisms and treated continuously with colistin for more than 72 hours were included in the study.

Results:

Patients were evaluated for clinical and microbiological response to the drug and its and side effects. Twelve newborn infants with mean 31.8 ± 3.5 weeks gestational age and median 1482 (810 - 3200) gram birth weight were included. 11/12 (91.7%) patients showed microbiological clearance with intravenous colistin. One patient who had recurrent cerebrospinal fluid positive culture was treated with intraventricular colistin. The major side effects observed was hyponatremia and hypokalemia in 2 (16.6%) patients, all infants required magnesium supplementation.

Conclusions:

Intravenous colistin administration appears to be safe and efficacious for multidrug-resistant gram-negative infections in neonates, including preterm infants. However, we believe that large prospective controlled studies are needed to confirm its efficacy and safety in neonates.  相似文献   
14.
15.
AimsTo assess whether there is an opportune window when intensive lifestyle intervention (ILI) benefits cognitive function.MethodsStandardized cognitive assessments were collected following ≥8 years of either ILI or a control condition of diabetes support and education (DSE) in 3708 individuals, ages 45-76 years at enrollment, with type 2 diabetes and overweight or obesity. Frailty index (FI) scores were used to group individuals at baseline into tertiles according to their age-related health status. Linear models were used to describe intervention adherence and cognitive function, with interaction terms to examine the consistency of relationships among tertiles.ResultsWorse baseline FI scores were associated with poorer subsequent performance in tests of attention, processing speed, and executive function. No differences in any measure of cognitive function were observed between intervention groups within any FI tertile (all p > 0.10). Among individuals with worse baseline FI scores, weight gain was associated with poorer global cognitive function among participants assigned to DSE. There was no association between weight changes and cognitive function among participants assigned to ILI.ConclusionsAmong adults with type 2 diabetes and overweight/obesity, we found no evidence that there is a window of opportunity based on FI when ILI benefits cognitive function.  相似文献   
16.
INTRODUCTION: Translocation of bacteria from the gut into pancreatic necrosis is an important factor in the development of septic complications and mortality in acute pancreatitis. S-methylisothiourea (SMT) is an inducible nitric oxide synthase inhibitor that has been shown to decrease bacteria] translocation in sepsis and thermal injury. AIM: To investigate whether SMT could affect bacterial translocation in acute necrotizing pancreatitis. METHODOLOGY: Forty-five Sprague-Dawley rats were studied. Acute pancreatitis was induced in Group I and Group II by injection of taurocholate and trypsin into the common biliopancreatic duct. Group III underwent laparotomy with the manipulation (but not cannulation) of the pancreas and received saline injection. Group I rats received normal saline as a placebo, and Group II rats received SMT after surgery for 2 days. At 48 hours, blood was drawn for serum amylase determinations. Bacterial translocation to mesenteric lymph nodes and distant sites (pancreas, liver, and peritoneum) were examined. A point scoring system of histologic features was used to evaluate the severity of pancreatitis. RESULTS: Plasma amylase levels and pancreatic histologic score were significantly reduced in Group II rats given SMT compared with those in Group I rats given saline (p < 0.01, p < 0.05, respectively). All Group I rats had bacterial translocation to mesenteric lymph nodes compared with 7 of 12 rats in Group II (p < 0.05). There was no difference in bacterial translocation to distant organs between the two groups, although rates tended to be lower in Group II compared with Group I (p > 0.05). Bacterial counts in the pancreas were significantly reduced in Group II rats compared with those in Group I rats (p < 0.05). CONCLUSION: Treatment with SMT appears to have ameliorated the course of acute pancreatitis; however, mortality was not affected.  相似文献   
17.
Plasma soluble adhesion molecules, intercellular adhesion molecule-1 (ICAM)-1, vascular cell adhesion molecule-1 (VCAM-1) and E-selectin leves of patients with isolated coronary artery ectasia (CAE), patients with obstructive coronary artery disease without CAE and subjects with angiographically normal coronary arteries were evaluated. Patients with isolated CAE were detected to have significantly higher levels of plasma soluble ICAM-1, VCAM-1 and E-selectin in comparison with patients with obstructive coronary artery disease without CAE (ICAM, 673 +/- 153 versus 381 +/- 106, respectively, P < 0.001; VCAM-1, 2366 +/- 925 versus 1136 +/- 208, respectively, P < 0.001; E-selectin, 74 +/- 21 versus 61 +/- 18, respectively, P = 0.01) and subjects with normal coronary arteries (ICAM-1, 673 +/- 153 versus 303 +/- 131, respectively, P < 0.001; VCAM-1, 2366 +/- 925 versus 729 +/- 231, respectively, P < 0.001; E-selectin, 74 +/- 21 versus 49 +/- 9, respectively, P < 0.001), suggesting the presence of a more severe and extensive chronic inflammation in the coronary circulation in patients with isolated CAE. BACKGROUND: The common coexistence of coronary artery ectasia (CAE) with coronary artery disease (CAD) suggests that it may be a variant of CAD. However, it is not clear why some patients with obstructive CAD develop CAE whereas most do not. Inflammation has been reported to be a major contributing factor to both obstructive and aneurysmatic vascular disorders and therefore, in the present study, the plasma soluble adhesion molecules, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin levels in isolated CAE were investigated. METHODS: The study population consisted of three groups: the first consisted of 32 patients with isolated CAE without stenotic lesion; the second of 32 patients with obstructive CAD without CAE; and the third group of 30 control subjects with normal coronary arteries. Coronary diameters were measured as the maximum diameter of the ectasic segment by use of a computerized quantitative coronary angiography analysis system. According to the angiographic definition used in the Coronary Artery Surgery Study, a vessel is considered to be ectasic when its diameter is > or =1.5 times that of the adjacent normal segment in segmental ectasia. Plasma soluble ICAM-1, VCAM-1 and E-selectin levels were measured in all patients and control subjects using commercially available enzyme-linked immunosorbent assay kits. RESULTS: Patients with isolated CAE were found to have significantly higher levels of plasma soluble ICAM-1, VCAM-1, and E-selectin in comparison with patients with obstructive CAD without CAE (ICAM, 673 +/- 153 versus 381 +/- 106, respectively; P < 0.001; VCAM-1, 2366 +/- 925 versus 1136 +/- 208, respectively; P < 0.001; E-selectin, 74 +/- 21 versus 61+/-18, respectively; P = 0.01) and control subjects with normal coronary arteries (ICAM-1, 673 +/- 153 versus 303 +/- 131, respectively;, P < 0.001; VCAM-1, 2366 +/- 925 versus 729 +/- 231, respectively; P < 0.001; E-selectin, 74 +/- 21 versus 49 +/- 9, respectively; P < 0.001). In addition, we detected statistically significant positive correlation between the total length of ectasic segments and the levels of plasma soluble ICAM-1 (r = 0.625; P < 0.001), VCAM-1 (r = 0.548; P = 0.001) and E-selectin (r = 0.390; P = 0.027). Multivariate logistic regression analysis revealed a significant independent relation between isolated CAE and ICAM-1 [odds ratio (OR) = 1.023; 95% confidence interval (CI) = 1.0048-1.0414; P = 0.0129] and VCAM-1 (OR = 1.0057; 95% CI = 1.0007-1.0106; P = 0.0240). CONCLUSIONS: We have shown that patients with isolated CAE have raised levels of plasma soluble ICAM-1, VCAM-1 and E-selectin in comparison with patients with obstructive CAD without CAE and control subjects with normal coronary arteries, suggesting the presence of a more severe and extensive chronic inflammation in the coronary circulation in these patients.  相似文献   
18.
OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies.  相似文献   
19.
20.
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