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   8863篇
  免费   340篇
  国内免费   52篇
耳鼻咽喉   276篇
儿科学   360篇
妇产科学   420篇
基础医学   607篇
口腔科学   318篇
临床医学   726篇
内科学   2209篇
皮肤病学   156篇
神经病学   475篇
特种医学   335篇
外科学   2090篇
综合类   134篇
预防医学   198篇
眼科学   314篇
药学   334篇
中国医学   24篇
肿瘤学   279篇
  2024年   2篇
  2023年   76篇
  2022年   123篇
  2021年   260篇
  2020年   143篇
  2019年   177篇
  2018年   218篇
  2017年   178篇
  2016年   289篇
  2015年   337篇
  2014年   453篇
  2013年   537篇
  2012年   678篇
  2011年   634篇
  2010年   418篇
  2009年   419篇
  2008年   634篇
  2007年   701篇
  2006年   633篇
  2005年   635篇
  2004年   533篇
  2003年   449篇
  2002年   354篇
  2001年   62篇
  2000年   41篇
  1999年   33篇
  1998年   44篇
  1997年   28篇
  1996年   32篇
  1995年   27篇
  1994年   14篇
  1993年   10篇
  1992年   17篇
  1991年   11篇
  1990年   9篇
  1989年   5篇
  1988年   7篇
  1987年   5篇
  1986年   4篇
  1985年   5篇
  1984年   4篇
  1983年   2篇
  1982年   2篇
  1980年   2篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
  1968年   2篇
  1966年   2篇
排序方式: 共有9255条查询结果,搜索用时 15 毫秒
101.
Objective:To assess the bone support of the teeth adjacent to a cleft using cone-beam computed tomography (CBCT).Materials and Methods:The CBCT scans of 31 patients with unilateral cleft lip and palate (UCLP) were assessed. The data for teeth neighboring the cleft were compared with those of contralateral noncleft teeth. For each tooth analyzed, the distance between the cementoenamel junction (CEJ) and the bone crest (AC) at the buccal side was measured as was the thickness of the buccal bone level at 0, 1, 2, and 4 mm.Results:The bone thicknesses of the central teeth at the cleft region at the crest and 2 mm apically were statistically significantly thinner than that of the central incisor at a noncleft region. The CEJ-AC distance for central teeth at the cleft region was higher than that for central teeth in a noncleft region.Conclusions:Subjects with UCLP showed reduced bone support at teeth neighboring the cleft compared with controls. This may cause some problems during orthodontic treatment.  相似文献   
102.
[Purpose] There are various treatment modalities for fibromyalgia syndrome (FMS), which is characterized by widespread pain and fatigue. The aim of this study was to investigate the effects of aquatic, aerobic and isometric strength-stretching exercises on the physical and psychological parameters of patients with FMS. [Subjects and Methods] Seventy five female patients with FMS were randomly selected and divided into three groups. Patients (18–50 years) were treated for 3 months using one of three methods: a home-based isometric strength and stretching exercise program (ISSEP), a gym-based aerobic exercise program (AEP), and a pool-based aquatic aerobic exercise program (AAEP). Items evaluated were: the number of tender points, Visual Analog Scale (VAS), Fibromyalgia Impact Questionnaire (FIQ), the Six-Minute Walk Test (6MWT), SF-36 physical and mental health scores, and the Beck Depression Inventory (BDI). [Results] The results revealed that AAEP was the most effective treatment of the three. All of the groups showed significant improvements in all variables between pre-and post-test, except the mean values of VAS and BDI in ISSEP. [Conclusion] The results suggest that aquatic aerobic exercise program is more effective than AEP and ISSEP in the treatment of FMS.Key words: Fibromyalgia, Exercise, Treatment  相似文献   
103.
104.
105.
BACKGROUND:Peripheral nerves can be injured by congenital, mechanical, thermal or chemical causes. Peripheral nerve injuries are increasing in frequency, particularly in countries that are becoming more industrialized. Nerve and extremity injuries result in work loss and high treatment costs, and can lead to separation of patients from their social environment. Failure of nerve repair causes muscle functional losses, sensory losses and painful neuropathies.OBJECTIVES:To compare the effects of condensed polytetrafluoroethylene (cPTFE) and cPTFE-extractum cepae-heparin-allantoin (cPTFE-EHA) gel compound on nerve and functional recovery, and the prevention of adhesion and scar tissue formation after total peripheral nerve injury repaired by primary suture in a rat model.RESULTS:cPTFE alone and cPTFE-EHA gel was found to provide better functional recovery and nerve regeneration compared with primary repair only. In the macroscopic evaluation, the cPTFE-EHA gel was found to have no negative effect on wound healing and, despite increasing extra-neural scar tissue and adhesions, it had no negative effect on nerve function; in addition, it facilitated functional recovery.CONCLUSIONS:Compared with the cPTFE application alone, the application of perineural cPTFE-EHA gel during peripheral nerve surgery appeared to provide better functional recovery without causing any significant changes in epineural and extraneural scar tissue formation.  相似文献   
106.
107.

Purpose

To compare the efficacy of RIRS and PNL in lower pole stones ≥2 cm. Materials and and Methods: A total of 109 patients who underwent PNL or RIRS for solitary lower pole stone between April 2009 and December 2012, were retrospectively analyzed. Lower pole stone was diagnosed with CT scan. Stone size was assessed as the longest axis of the stone. All patients were informed about the advantages, disadvantages and probable complications of both PNL and RIRS before the selection of the procedure. Patients decided the surgery type by themselves without being under any influences and written informed consent was obtained from all patients prior to the surgery. Patients were divided into two groups according to the patients’ preference of surgery type. Group 1 consisted of 77 patients who underwent PNL and Group 2 consisted of 32 patients treated with RIRS. Stone free statuses, postoperative complications, operative time and hospitalization time were compared in both groups.

Results

There was no statistical significance between the two groups in mean age, stone size, stone laterality, mean follow-up periods and mean operative times. In PNL group, stone-free rate was 96.1% at first session and 100% after the additional procedure. In Group 2, stone-free rate was 90.6% at the first procedure and 100% after the additional procedure. The final stone-free rates and operative times were similar in both groups.

Conclusions

RIRS should be an effective treatment alternative to PNL in lower pole stones larger than 2 cm, especially in selected patients.  相似文献   
108.
Laparoscopy began to be used widely since the second half of 1990s as an alternative to laparotomy or vaginal approaches in incontinence and pelvic diseases in women, based on its claimed better success rates. Injuries were reported in the bladder, gastrointestinal system and the entry of the Verress cannula in early and late laparoscopic applications. De-novo urging, voiding dysfunctions, marked recurrences and surgical inefficiencies were observed in 5-year follow-ups after laparoscopic incontinence surgery. Although tension-free midurethral sling operations replaced open laparoscopic colposuspensions nowadays, laparoscopic colposuspension is still preferred in cases where simultaneous laparoscopic paravaginal repair or sacrocolpopexy is considered or where synthetic graft implantation is contraindicated. Moreover, meshes and endotackers are still frequently used in many laparoscopic applications in various clinics. The migration of the tacker used in mesh fixation in a patient where retroperitoneal laparoscopic Burch was performed 7 years ago due to stress urinary incontinence and the extraction of the ossified tacker from the bladder will be presented.  相似文献   
109.
In this multicenter, retrospective study, we evaluated the efficacy and safety of biologic therapies, including anti-TNFs, in secondary (AA) amyloidosis patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). In addition, the frequency of secondary amyloidosis in RA and AS patients in a single center was estimated. Fifty-one AS (39M, 12F, mean age: 46.7) and 30 RA patients (11M, 19F, mean age: 51.7) with AA amyloidosis from 16 different centers in Turkey were included. Clinical and demographical features of patients were obtained from medical charts. A composite response index (CRI) to biologic therapy—based on creatinine level, proteinuria and disease activity—was used to evaluate the efficacy of treatment. The mean annual incidence of AA amyloidosis in RA and AS patients was 0.23 and 0.42/1000 patients/year, respectively. The point prevalence in RA and AS groups was 4.59 and 7.58/1000, respectively. In RA group with AA amyloidosis, effective response was obtained in 52.2 % of patients according to CRI. RA patients with RF positivity and more initial disease activity tended to have higher response rates to therapy (p values, 0.069 and 0.056). After biologic therapy (median 17 months), two RA patients died and two developed tuberculosis. In AS group, 45.7 % of patients fulfilled the criteria of good response according to CRI. AS patients with higher CRP levels at the time of AA diagnosis and at the beginning of anti-TNF therapy had higher response rates (p values, 0.011 and 0.017). During follow-up after anti-TNF therapy (median 38 months), one patient died and tuberculosis developed in two patients. Biologic therapy seems to be effective in at least half of RA and AS patients with AA amyloidosis. Tuberculosis was the most important safety concern.  相似文献   
110.
The aim of this study was to determine the prevalence of alpha (ESR1: c.454-397T>C and c.454-351A>G) and beta (ESR2: 1082G>A and 1730G>A) estrogen receptor gene polymorphisms in 2 Brazilian ethnic groups (Caucasian, African Brazilian) and to investigate their association with recurrent miscarriage (RM) in 75 women with a history of 3 or more consecutive pregnancy losses and 139 controls with at least 2 live births and no history of pregnancy loss. Polymerase chain reaction and restriction fragment length polymorphism were used to identify gene polymorphisms. Coagulation methods were used to measure protein C, protein S, and fibrinogen, and a chromogenic method was used for antithrombin quantification. Significantly higher prevalences of 1082G>A and 1730G>A polymorphisms were seen in African Brazilian and Caucasian controls, respectively. There was no association between RM and ESR polymorphisms. There was a difference in the genotype prevalence in the c.454-39T>C polymorphism between RM and control Caucasians, but this finding was not associated with an increased risk of miscarriage. There was no synergistic or additive effect between ESR polymorphisms and thrombophilia in RM patients. A difference in the prevalence of ESR polymorphisms was observed, according to ethnic origin. ESR polymorphisms could not be considered a risk factor for RM.  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