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   16625篇
  免费   1086篇
  国内免费   198篇
耳鼻咽喉   227篇
儿科学   424篇
妇产科学   836篇
基础医学   2050篇
口腔科学   303篇
临床医学   1748篇
内科学   3522篇
皮肤病学   417篇
神经病学   958篇
特种医学   617篇
外科学   2431篇
综合类   554篇
现状与发展   2篇
一般理论   3篇
预防医学   854篇
眼科学   296篇
药学   1173篇
  1篇
中国医学   176篇
肿瘤学   1317篇
  2023年   82篇
  2022年   242篇
  2021年   450篇
  2020年   230篇
  2019年   332篇
  2018年   432篇
  2017年   307篇
  2016年   306篇
  2015年   491篇
  2014年   627篇
  2013年   773篇
  2012年   1154篇
  2011年   1137篇
  2010年   756篇
  2009年   615篇
  2008年   918篇
  2007年   920篇
  2006年   840篇
  2005年   838篇
  2004年   717篇
  2003年   590篇
  2002年   550篇
  2001年   491篇
  2000年   423篇
  1999年   368篇
  1998年   171篇
  1997年   155篇
  1996年   131篇
  1995年   110篇
  1994年   120篇
  1993年   79篇
  1992年   194篇
  1991年   182篇
  1990年   159篇
  1989年   148篇
  1988年   134篇
  1987年   152篇
  1986年   125篇
  1985年   99篇
  1984年   91篇
  1983年   74篇
  1981年   55篇
  1980年   54篇
  1979年   62篇
  1978年   55篇
  1972年   60篇
  1958年   60篇
  1957年   88篇
  1955年   76篇
  1954年   68篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
BackgroundGeneric antidepressants are approved on the market based on evidence of bioequivalence to their brand-name versions. We aimed to assess whether generic antidepressants exert equal effectiveness as their brand-name counterparts for treating patients with depressive disorders.MethodsIn a nationwide, population-based cohort in Taiwan from 1997 through 2013, patients with a diagnosis of a depressive disorder aged between 18 and 65 years who were new users of antidepressant drugs were classified into either the brand-name group or the generic group. All patients were followed up until medication discontinuation or the end of the study period. We assessed the risk for hospitalization as a primary outcome and augmentation therapy, daily dose, medication discontinuation, or switching to another antidepressant as secondary outcomes.ResultsA total of 277 651 brand-name users (35.8% male; mean age: 41.2 years) and 270 583 generic users (35.8% male; mean age: 41.0 years) were divided into 10 different antidepressant groups (fluoxetine, sertraline, paroxetine, escitalopram, citalopram, venlafaxine, mirtazapine, moclobemide, imipramine, and bupropion). We found that patients treated with the generic form of sertraline, paroxetine, escitalopram, venlafaxine, mirtazapine, and bupropion demonstrated significantly higher risks of psychiatric hospitalization (adjusted hazard ratios ranged from 1.20–2.34), compared to their brand-name counterparts. The differences between brand-name antidepressants and their generic counterparts in secondary outcomes varied across different drugs.ConclusionsCompared to most generic antidepressants, brand-name drugs exhibited more protective effects on psychiatric hospitalization for depressive patients. These findings could serve as an important reference for clinicians when encountering patients with depressive disorder.  相似文献   
5.
6.
Thoracic empyema in uremic patients on maintenance hemodialysis is a challenging situation. The clinical characteristics are rarely reported, and the surgical outcomes remain unclear. We report our experience with video-assisted thoracoscopic surgery in these patients during 10-year period of time. Between 2005 and 2015, we retrospectively reviewed the clinical characteristics, bacteriological studies, and thoracoscopic surgical results of 23 empyema patients undergoing maintenance hemodialysis. The mean patient age was 67.1 ± 12.9 years. All patients had additional preexisting systemic diseases. The mean duration of hemodialysis was 34.7 ± 25.8 months. The infections causing empyema were pneumonia in 11 (47.8%), blood stream infection in 8 (34.8%), and uremic pleuritis in 4 (17.4%). Among the 22 identified microorganisms, the most common pathogen was methicillin-resistant Staphylococcus aureus (31.8%). After thoracoscopic surgery, 8 patients (34.8%) required additional procedures for complications, including 2 patients who required repeated thoracoscopy for hemothorax and 6 (26.1%) patients who required open drainage for residual empyema. The mean hospital stay was 62.4 days, and 6 patients (26.1%) died in the hospital. Univariate and multivariate analyses revealed that maintenance hemodialysis longer than 5 years was a significant factor associated with in-hospital mortality (odds ratio: 14.8, 95% confidence interval 1.5–151.6; p < 0.0001). While surgical management of thoracic empyema in uremic patients undergoing maintenance hemodialysis is associated with high rates of complication and mortality, thoracoscopic surgery is feasible, especially for patients undergoing hemodialysis for less than 5 years.  相似文献   
7.
Zygomatic implant treatment is widely applied for severe maxillary atrophy to help rehabilitate the maxillary dentition. This retrospective study was performed to evaluate the actual radiographic bone–implant contact (rBIC) lengths of zygomatic implants. The records of 28 patients who underwent zygomatic implant surgery and subsequent follow-up examinations between August 2013 and September 2018 in the Department of Oral and Maxillofacial Surgery, Taipei Tzu Chi Hospital were reviewed. The surgeries were performed by a single surgeon using the same treatment protocol. All patients had a computed tomography scan at 1 year after the surgery. Using three-dimensional imaging software, an investigator measured the rBIC lengths of 66 implants and documented their clinical status. The implant survival rate was 100%. The mean rBIC length was significantly longer in male patients than in female patients (20.80 ± 5.88 mm versus 17.79 ± 6.34 mm; P = 0.028). The mean rBIC length of double zygomatic implants was significantly longer when compared to that of single implants (21.11 ± 6.23 mm versus 17.75 ± 5.85 mm; P = 0.027). This article is novel in reporting the exact rBIC lengths of zygomatic implants in a clinical setting. The results showed that zygomatic implants are a viable treatment modality for full-mouth rehabilitation.  相似文献   
8.
9.
PURPOSE: The aim of this study was to investigate the effects of bimatoprost 0.03% on ocular hemodynamics in patients with normal tension glaucoma (NTG). METHODS: Twenty-two (22) patients with NTG were consecutively recruited. After basic eye examination and diurnal intraocular pressure (IOP) measurement, color Doppler imaging was used to measure the peak systolic and end diastolic velocities and resistive index of the central retinal, lateral posterior ciliary, and medial posterior ciliary arteries. Patients received bimatoprost 0.03% for 4 weeks, and these measurements were then repeated. The worse eye of each NTG patient was used in the statistical analysis. RESULTS: Bimatoprost 0.03% significantly reduced mean IOP from 15.1 +/- 3.8 mmHg at baseline to 12.0 +/- 2.9 mmHg after treatment in our sample of NTG patients (P < 0.001). No significant changes in blood velocities or resistance indices were observed in the retrobulbar vessels after the 4-week treatment. CONCLUSIONS: Topical bimatoprost 0.03% significantly reduced IOP in our NTG patients without causing significant hemodynamic changes in the retrobulbar vessels.  相似文献   
10.
In one eye each of four cynomolgus monkeys, an 8-mm penetrating injury was made through the equator; there was retinal perforation with vitreous loss. None of the four eyes with this injury developed posterior vitreous detachment or retinal detachment during a follow-up period of 8 months to 1 year.Another group of 26 monkeys had the same injury but also had 0.5 ml autologous whole blood injected into the vitreous at the time of injury. The eyes were examined weekly and enucleated at scheduled intervals from 1 day to 52 weeks post-injury. Posterior vitreous detachment occurred at the earliest at 2 weeks post-injury, and was ultimately present in 91% of the eyes. Vitreous detachment can occur either as a separation at the level of the internal limiting membrane or as a cleavage within the cortical vitreous. Retinal detachment occurred at the earliest at 8 weeks post-injury, and eventually was present in 50% of the eyes. The retinal detachment was tractional; no retinal breaks were detected in any of the eyes.This study was supported by grants EY02061 and EY03040 from the National Institutes of HealthPresented at the 1984 meeting of the Club Jules Gonin in Lausanne, Switzerland  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