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   733篇
  免费   28篇
  国内免费   3篇
耳鼻咽喉   74篇
儿科学   8篇
妇产科学   51篇
基础医学   34篇
口腔科学   83篇
临床医学   48篇
内科学   156篇
皮肤病学   12篇
神经病学   39篇
特种医学   17篇
外科学   182篇
综合类   10篇
预防医学   16篇
眼科学   10篇
药学   14篇
中国医学   2篇
肿瘤学   8篇
  2023年   7篇
  2022年   6篇
  2021年   21篇
  2020年   6篇
  2019年   16篇
  2018年   20篇
  2017年   21篇
  2016年   21篇
  2015年   29篇
  2014年   50篇
  2013年   44篇
  2012年   60篇
  2011年   62篇
  2010年   34篇
  2009年   37篇
  2008年   62篇
  2007年   48篇
  2006年   56篇
  2005年   42篇
  2004年   51篇
  2003年   23篇
  2002年   35篇
  2001年   2篇
  2000年   2篇
  1999年   1篇
  1998年   1篇
  1997年   2篇
  1996年   1篇
  1994年   1篇
  1992年   2篇
  1985年   1篇
排序方式: 共有764条查询结果,搜索用时 250 毫秒
1.
2.
Abstract

Purpose: To compare the efficacy, safety, and potential advantages of the preservative-free versus preserved brimonidine %0.15 preparations in patients with primer open-angle glaucoma (POAG) or ocular hypertension (OHT).

Methods: Forty-two eyes of the 21 treatment-naive patients with POAG or OHT were enrolled in this study. Eyes were randomly assigned to receive brimonidine-purite 0.15% or preservative-free brimonidine 0.15% two times daily. Efficacy of the two eye drops was assessed by measuring the intraocular pressure (IOP) at 9–10 am at baseline and week 4. Safety and potential advantages of the drops were evaluated at weeks 4 in terms of ocular symptoms and tear parameters. Ocular symptom values of the patients were evaluated with a scale of 0–4 (0?=?no discomfort and 4?=?severe discomfort).

Results: Both of the brimonidine tartrate formulations resulted in statistically similar IOP reduction (preserved formulation; ?5.2?mmHg [22.9% reduction] preservative-free formulation; ?5.7?mmHg [24.1% reduction], p?=?0.37). It was found that brimonidine tartrate formulations with and without topical preservatives did not produce a statistically significant difference in pain, stinging, and blurred vision at the upon instillation (p?>?0.05). However, the burning sensation was significantly higher in the preservative-free formulation at the first instillation compared to the preserved formulation (p?=?0.01). Also, there was no statistically significant difference between the two formulations in terms of symptoms (itching, burning, tearing, stinging, and photophobia) and tear parameters during the day (p?>?0.05).

Conclusions: Although topical preservative-free brimonidine tartrate treated eyes had a more burning sensation at the first drop, the two formulations were similar in terms of ocular tolerability in the short term period. Also, both formulations were found to reduce IOP at a similar rate.  相似文献   
3.
4.
ObjectiveIntrahepatic cholestasis of pregnancy is a temporary, pregnancy-specific disease that resolves with delivery, characterized by itching (pruritus), as well as high transaminase and serum bile acid levels in the third trimester of pregnancy. Due to the effects of Autotaxin on the physiology of pregnancy, we aimed to investigate Autotaxin activity in patients with intrahepatic cholestasis of pregnancy.Patients and methodsSixty-nine patients diagnosed with intrahepatic cholestasis of pregnancy and 20 healthy pregnant women were enrolled in the study. Fasting serum bile acid, pruritus intensity, serum parameters, gestational week of the patients at the time of diagnosis were recorded, and birth week and birth weight were monitored. Autotaxin serum level was measured enzymatically.ResultsThe mean serum bile acid level (n = 69; 38.74 ± 35.92 μmol/L) in patients with intrahepatic cholestasis of pregnancy (n = 69) was detected to be higher than healthy pregnant women (n = 20; 5.05 ± 1.88 μmol/L) (p < 0.001). Weak correlation was detected between serum bile acid level and itch intensity (p = 0.014, r = 0.295), while no relation was detected between Autotaxin and itch intensity (p = 0.446, r = 0.09). Although mean Autotaxin (intrahepatic cholestasis of pregnancy: 678.10 ± 424.42 pg/mL, control: 535.16 ± 256.47 pg/mL) levels were high in patients with intrahepatic cholestasis of pregnancy, it was not statistically significant (p = 0.157).ConclusionIn our study, we observed that the serum Autotaxin level did not make a significant difference in patients with intrahepatic cholestasis of pregnancy compared to healthy pregnant women. These findings suggest that larger clinical studies are required to reveal the physio-pathological effects of Autotaxin on pregnancy.  相似文献   
5.
This article describes a time-saving technique for fabricating a new implant-retained orbital prosthesis using the patient's existing prosthesis. The location of the ocular component is transferred; the position and openings of the palpebral anatomic structures and the precise anatomic details of the existing orbital prosthesis are duplicated. Making the impression, fabricating the definitive cast, alignment of the ocular component, and completing the wax sculpture of the prosthesis are accomplished in one appointment.  相似文献   
6.
OBJECTIVE: Different types of fibers have been added to polymer materials to improve their mechanical properties. Glass fibers have been used in either continuous or woven form as a strengthening material. The aim of this study was to investigate the effect of a new glass fiber reinforcement system on the flexural strength of three different denture base resins (heat polymerized, autopolymerized, and photopolymerized). METHOD AND MATERIALS: Ninety specimens were formed in a specially designed mold to produce identical specimens in accordance with each manufacturer's recommendations. RESULTS: The fibers of Stick and Stick Net were well impregnated with the resin of polymer matrix. Stick and Stick Net reinforcement significantly enhanced the flexural strength of the tested specimens. In all groups, specimens reinforced with Stick glass fibers exhibited the highest flexural strength, followed by Stick Net glass fibers. The control group specimens without fiber exhibited the lowest values. CONCLUSION: The process of reinforcement of denture base resins with glass fiber may be a useful means of strengthening denture bases beyond their normal limits.  相似文献   
7.
PURPOSE: Patterns of von Mises stress values surrounding implants supporting fixed prostheses in the posterior edentulous maxilla were evaluated using 3-dimensional finite element analysis. MATERIALS AND METHODS: Implants were placed in maxillary bone in 2 different configurations. In the first configuration, implants were placed in the first premolar, second premolar, and second molar regions; in the second configuration, implants were placed in the second premolar and second molar regions, and a mesial cantilever was extended to the space of the first premolar tooth on the superstructure. On the implant placed in the socket of the second molar, 3 different inclinations were used (0, 15, and 30 degrees). Loading was applied in the vertical, oblique, and horizontal axes. RESULTS: Inclination of the implant in the molar region was found to result in increased stress. Significant increase in stress on the implant embedded in the premolar region was also seen in the design with the cantilever as compared to the conventional prosthesis design. Discussion: The stress concentrations observed at the neck of the implant were similar to results reported in the literature. CONCLUSION: The highest stress value obtained in the study was 194.2 MPa with oblique loading. This value did not exceed the endurance limit of pure titanium, which is 259.9 MPa.  相似文献   
8.
The aims of this study were to evaluate the success rates and peri-implant soft tissue responses of auricular implants, to assess prosthetic complications, and to calculate the survival rate of silicone auricular prostheses. Twenty-nine extraoral implants were placed in 10 patients with 11 auricular defects. Implant failure was defined as clinically detectable implant mobility, and a 5-point scale was used to record the health of peri-implant soft tissues. Prosthetic complications were assessed, and the survival rate of silicone auricular prostheses was calculated using Kaplan-Meier analysis. The implant success rate was 100%. A few soft tissue problems were noted. The overall cumulative survival rate for the first prostheses of the patients was 70% after 18 months. The mean survival time was 17 months. Extraoral implants had a very high success rate in the mastoid region. Prosthetic assessment indicated that although experience with wearing prostheses reduces retention degradation, discoloration and reduced quality of fit at the prosthesis edge over time remain the major problems in maxillofacial prosthetics.  相似文献   
9.

PURPOSE

The purpose of the present study was to evaluate the effect of thermocycling and mechanical loading on the biaxial flexural strength and the phase transformation of one Ce-TZP/Al2O3 and two Y-TZP core materials.

MATERIALS AND METHODS

Thirty disc-shaped specimens were obtained from each material. The specimens were randomly divided into three groups (control, thermocycled, and mechanically loaded). Thermocycling was subjected in distilled water for 10000 cycles. Mechanical loading was subjected with 200 N loads at a frequency of 2 Hz for 100000 times. The mean biaxial flexural strength and phase transformation of the specimens were tested. The Weibull modulus, characteristic strength, 10%, 5% and 1% probabilities of failure were calculated using the biaxial flexural strength data.

RESULTS

The characteristic strengths of Ce-TZP/Al2O3 specimens were significantly higher in all groups compared with the other tested materials (P<.001). Statistical results of X-ray diffraction showed that thermocycling and mechanical loading did not affect the monoclinic phase content of the materials. According to Raman spectroscopy results, at the same point and the same material, mechanical loading significantly affected the phase fraction of all materials (P<.05).

CONCLUSION

It was concluded that thermocycling and mechanical loading did not show negative effect on the mean biaxial strength of the tested materials.  相似文献   
10.

Objective

To investigate the role of small dense low density lipoprotein cholesterol (sd-LDL-C) in the mechanism of decreased incidence of cardiovascular disease in Gilbert's syndrome (GS).

Design and methods

sd-LDL-C, ox-LDL, and high sensitive C reactive protein (hs-CRP) levels were investigated in subjects with GS (n = 42) and compared to healthy controls (n = 52).

Results

Age, gender and body mass index (BMI) distributions were similar between the two groups. sd-LDL-C, ox-LDL and hs-CRP levels were lower in GS than the healthy controls (p < 0.001, p < 0.001 and p = 0.001, respectively). Unconjugated bilirubin was negatively correlated with sd-LDL-C, ox-LDL and hs-CRP (r = −0.594, p < 0.001; r = −0.249, p = 0.016 and r = − 0.373, p < 0.001 respectively). In addition, sd-LDL-C was positively correlated with ox-LDL (r = 0.307, p = 0.003).

Conclusions

The findings of this preliminary study suggest that reduced sd-LDL-C, ox-LDL and hs-CRP levels may have a role in preventing atherosclerosis in subjects with GS.  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