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   1033篇
  免费   72篇
  国内免费   35篇
耳鼻咽喉   3篇
儿科学   27篇
妇产科学   8篇
基础医学   99篇
口腔科学   22篇
临床医学   94篇
内科学   234篇
皮肤病学   13篇
神经病学   34篇
特种医学   128篇
外科学   124篇
综合类   89篇
预防医学   81篇
眼科学   30篇
药学   111篇
肿瘤学   43篇
  2022年   7篇
  2021年   18篇
  2020年   7篇
  2019年   16篇
  2018年   27篇
  2017年   22篇
  2016年   24篇
  2015年   20篇
  2014年   28篇
  2013年   52篇
  2012年   53篇
  2011年   59篇
  2010年   26篇
  2009年   41篇
  2008年   47篇
  2007年   67篇
  2006年   54篇
  2005年   45篇
  2004年   37篇
  2003年   27篇
  2002年   25篇
  2001年   20篇
  2000年   19篇
  1999年   25篇
  1998年   39篇
  1997年   25篇
  1996年   25篇
  1995年   21篇
  1994年   19篇
  1993年   17篇
  1992年   9篇
  1991年   20篇
  1990年   8篇
  1989年   20篇
  1988年   21篇
  1987年   16篇
  1986年   13篇
  1985年   8篇
  1984年   10篇
  1983年   14篇
  1982年   9篇
  1981年   12篇
  1980年   11篇
  1979年   4篇
  1978年   9篇
  1977年   5篇
  1975年   13篇
  1974年   9篇
  1973年   4篇
  1972年   4篇
排序方式: 共有1140条查询结果,搜索用时 15 毫秒
61.
62.
BACKGROUND: It is unclear whether proactive telephone support enhances smoking cessation beyond the provision of nicotine replacement therapy alone. METHODS: We randomly assigned 330 low-income women smokers to receive either free nicotine patches (control condition) or free nicotine patches with up to 16 weeks of proactive telephone support (experimental condition). All participants were assessed by telephone at baseline and at 2 weeks, 3 months, and 6 months post-baseline to determine smoking status. RESULTS: Results revealed a significant effect for the telephone support at 3 months, with 43% of experimental versus 26% of control condition women reporting 30-day point prevalent abstinence (P = 0.002). The difference was no longer significant at 6 months. A metaanalysis conducted with five randomized studies revealed a slight but non-significant long-term benefit of proactive telephone support when added to the provision of free nicotine patches for smoking cessation. CONCLUSIONS: This is the second study to demonstrate a short-term effect for proactive telephone support added to free nicotine replacement therapy; however, neither the current study, nor the metaanalysis including the four other published trials, confirmed a longer-term benefit.  相似文献   
63.
OBJECTIVE: Here, we report the results of a randomized controlled trial (RCT) assessing the efficacy of emergency ESWL (eESWL) on the short-term outcome of symptomatic ureteral stones. MATERIAL: The trial enrolled 100 patients admitted in emergency room for renal colic caused by a ureteral radioopaque [corrected] stone. Patients were randomized to medical therapy alone or combined with eESWL. eESWL was performed within 6 hours of the onset of renal colic without specific analgesia on a Lithostar lithotripter (Siemens Medical, Munich, Germany). The primary endpoints were the proportion of patients stone free rate after 48 hours (SF-48) and the cumulative proportion of patients discharged from the hospital after 48 and 72 hours. RESULTS: Ureteral stone's location was proximal and distal in respectively 46% and 54% of the patients; stone's mean size was 5.5 mm (range 2-10 mm). Median hospital stay was 3 days, ranging from 1 to 14 days. SF-48 in the control group varied from 76% for distal stones <5 mm to 28.6% for proximal stones >5 mm, averaging at 61%. On average, eESWL increased SF-48 by 13% (p: 0.126), the gain strictly depending on stone size and location. SF-48 increase ranged from 40% for proximal stones >5 mm to 1.8% for distal stone <5 mm. On average, eESWL increased the median duration of hospital stay by one day. This mean negative impact results from ESWL increasing significantly the duration of hospital stay in case of distal stone, while slightly shortened it for stones located proximally. CONCLUSION: This study demonstrated for the first time that rapidly performed ESWL is a valuable therapeutic option to improve elimination of ureteral stones and shorten duration of hospital stay, proven that the stone is located proximally to the iliac vessels.  相似文献   
64.

Background

HBV DNA quantitation is used extensively world wide for the diagnosis and monitoring of treatment of Hepatitis B virus (HBV) infection. However, it has still to be popular in India. The aim of this study was to quantitate HBV – DNA by Real time – PCR method in Hepatitis B and in immuno-compromised patients, to compare the results with HBeAg detection and to monitor the response to therapy of chronic Hepatitis B patients to antivirals.

Methods

Ninety one serum samples of Hepatitis group of patients (all HBsAg positive), 41 samples from immuno-compromised patients (all HBsAg negative) and 49 patients of Chronic Hepatitis B group (all HBsAg positive) were the subjects of this first ever study in Armed Forces. Twenty serum samples from healthy volunteers and non-hepatitis B patients served as negative controls. The amplification detection was carried out in a Rotor-Gene 2000-sequence detector

Results

Amongst Hepatitis B group, 33% (30/91) of the samples were positive for HBV-DNA and 26% (24/91) of samples were positive for HBeAg. In the immuno-compromised group of patients 14.6% (6/11) of samples were positive for HIV-DNA and 9.7% (4/41) were positive for HBeAg. Of the Chronic Hepatitis B patients on treatment, all (100%) were positive by HBV-DNA, whereas 29/49 (59.2%) were positive by HBeAg before treatment. After treatment with antivirals, 06/49 (12.2%) were positive by both tests and 11/49 (22.5%) were positive only by HBV-DNA. 32/49 (65.3%) patients became negative serologically after therapy.

Conclusion

HBeAg status did not necessarily reflect HBV-DNA level in the serum, as 10/91 (11%) in the Hepatitis B group, 2/41 (4.9%) in the immuno compromised group and 20/49 (40.8%) patients in the Chronic Hepatitis B group were positive for HBV-DNA but negative for HBeAg. HBV-DNA was not found to be positive amongst any of the negative controls. Real time – PCR is a sensitive and reproducible assay for HBV-DNA quantitation and may be started in Armed Forces referral centers in the near future.Key Words: Real time – PCR, Chronic Hepatitis B, HBV – DNA, Antivirals  相似文献   
65.
Erectile dysfunction (ED) and depression are highly prevalent and frequently comorbid. Sildenafil effectively treats ED in men with depression and in men taking antidepressants. We evaluated the efficacy of sildenafil in men with depression in remission and ED. Patients with a history of ED when major depressive disorder (MDD) was diagnosed, which persisted after MDD was treated to remission, were randomized to 12 weeks of treatment with sildenafil (50 mg, flexible) or placebo. Efficacy was assessed using intercourse success rates, a global efficacy question (Has treatment improved your erections?), the International Index of Erectile Function (IIEF) and Life Satisfaction Checklist (LSC). By week 12, intercourse success rates were significantly higher among sildenafil- (74%) compared to placebo-treated patients (29%; P=0.0001). About 83% and 34% of sildenafil- and placebo-treated patients, respectively, reported improved erections (odds ratio=9.4, P=0.0001). IIEF scores in the sildenafil group (n=83) were significantly improved compared to those in the placebo group (n=85; P <0.0001). LSC sexual life item improved significantly among sildenafil- versus placebo-treated patients. The most frequently reported adverse events were transient and mild-to-moderate. Sildenafil is an effective and well-tolerated treatment for ED in patients with a history of ED at the time of MDD diagnosis, and which persisted after the MDD was treated to remission.  相似文献   
66.
PURPOSE: We evaluated the frequency of long-term complications of orbital irradiation (radiation-induced tumors, cataract, and retinopathy) in comparison with glucocorticoids. DESIGN: We conducted a follow-up study in a cohort of 245 Graves' ophthalmopathy patients who had been treated with retrobulbar irradiation (20 Gy in 2 weeks) and/or oral glucocorticoids between 1982 and 1993 in our institution. Irradiated patients were compared with nonirradiated patients. METHODS: Data on mortality and cause of death were obtained. Living patients were invited to participate in a follow-up study. Possible retinopathy was assessed in a masked fashion and defined as the presence of > or =1 hemorrhages and/or microaneurysms on red-free retina photographs. If >5 lesions were present, patients were categorized as suffering from definite retinopathy. Cataract was assessed using the Lens Opacity Classification System II score. MAIN OUTCOME MEASURES: Mortality, prevalence of retinopathy, prevalence of cataract, and type of cataract. RESULTS: Thirty-seven of the 245 patients had died, none of them from an intracranial tumor. Mortality was similar in the irradiated (27/159 [17%]) and nonirradiated patients (10/86 [12%]; P = 0.264). One hundred fifty-seven of the 208 living patients (75%) consented to participate in a follow-up ophthalmologic investigation; the mean follow-up time (+/- standard deviation) was 11+/-3 years. Possible retinopathy was present in 15% of patients, 22 of the irradiated and 1 of the nonirradiated patients (P = 0.002). In 5 patients (all had been irradiated), definite retinopathy (i.e., >5 retinal lesions) was present. Of these, 3 had diabetes mellitus, and 1 had hypertension. Diabetes was associated with both possible (P = 0.029) and definite (P = 0.005) retinopathy, with a relative risk of 21 (95% confidence interval, 3-179). The prevalence and severity of cataract were similar in the radiotherapy group (29%) and the glucocorticoid group (34%); it should be noted that 88 of 104 of the irradiated patients were also treated with oral glucocorticoids. CONCLUSION: The data suggest that orbital irradiation for Graves' ophthalmopathy is a safe treatment modality, except possibly for diabetic patients.  相似文献   
67.
An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) occurred on a head and neck surgical (HNS) ward of a university hospital in Amsterdam. The outbreak lasted from May 2000 until November 2000, and MRSA spread to two intensive care units. Amplified fragment length polymorphism analysis indicated that a single clone was responsible for the outbreak. Phage-typing indicated that this clone was of a type that was uncommon in The Netherlands. Strict isolation of patients, according to the Dutch national guidelines, was instituted. During the outbreak, surveillance culture specimens, from patients, healthcare workers, and the environment, were obtained at regular intervals. MRSA was found in the dust filters of nebulizers through which air from the room was filtered and subsequently humidified. These nebulizers were used to humidify tracheostomies. The dust filters were not maintained according to the guidelines. Restricted use and cleaning and disinfection of all ultra-sonic nebulizers led to termination of the outbreak. The outbreak illustrates that to terminate transmission of outbreak strains of MRSA, meticulous measures are necessary, which not only include strict isolation precautions, but also decontamination of the environment. In addition, it demonstrates the necessity of adhering to cleaning and disinfection guidelines for all medical and nursing equipment used in the hospital.  相似文献   
68.

Background  

The Major Depression Inventory (MDI) is a brief self-rating scale for the assessment of depression. It is reported to be valid because it is based on the universe of symptoms of DSM-IV and ICD-10 depression. The aim of the current preliminary study was to assess the reliability, validity and psychometric properties of the Greek translation of the MDI.  相似文献   
69.
Background Quantification of fibrinolytic activity (FAct) in clinical practice has been abandoned because of the complexity of existing assays. The relationship between thrombolytic drug concentration and FAct is complex. FAct profiles of currently used thrombolytic drugs were not characterized. Methods By use of a system that quantifies FAct by shortening of clot lysis onset time (LOT), we measured LOT in vitro with incremented concentrations of alteplase (t-PA) and tenecteplase (TNK-tPA) and ex vivo in patients with acute myocardial infarction who were receiving front-loaded t-PA (n = 31), 30 to 40 mg TNK-tPA (n = 19), and 120 kU/kg lanoteplase ([n-PA] n = 23). Results In vitro, FAct depended on drug concentration by means of a double exponential model revealing 2 distinct activity zones (weak/strong). Ex vivo, no FAct was detected before agent administration (LOT > 1200 seconds). Ten minutes after a bolus was given, FAct was sharply increased in all patients, but it increased more with TNK-tPA than with t-PA or n-PA (mean LOT of 109, 125, and 130 seconds, respectively, P < .05). At 90 minutes, accelerated infusion of t-PA resulted in FAct that remained stronger than that observed for TNK-tPA (P < .0001) or n-PA (P = .011). At 180-minutes, significant FAct (LOT <600 seconds) was only observed in patients who received n-PA. Conclusion This study provides the first direct comparison of FAct between t-PA, TNK-tPA, and n-PA by use of the LOT test, the results of which are reliably related to drug concentration. The ideal FAct profile would combine an immediate strong FAct of relatively short duration, as seen with TNK-tPA, that may contribute to its better efficacy/safety profile in the Assessment of Safety and Efficacy of a New Thrombolytic Agent-2 (ASSENT-2) trial. Prolonged FAct after n-PA may contribute to increased hemorrhagic complications, as seen in the Intravenous n-PA for Treatment of Infarcting Myocardium Early-2 (InTIME-2) trial. Thus, characterizing FAct profiles might provide insights in developing more efficient thrombolytic regimens. (Am Heart J 2003;145:217-25)  相似文献   
70.
Patient satisfaction is an important outcome measure independent of other outcomes. Its measurement is important to assess the effectiveness of a programme and to gain insight into the patients'' perception of the programme. In this study conducted in a large rehabilitation centre it was found that majority of patients express satisfaction with care inspite of perceived discomfort. Various demographic factors, severity or duration of the disability or the level of rehabilitation do not influence patient satisfaction. Patients express more concern with aspects such as delay in issue of the prosthesis, or hotel component of the hospital services. Patients did not appear too concerned about the level of information provided. Patient satisfaction is an individual reaction to the overall care process and is influenced by the initial expectation level of the patient. Emotional response of the patient appears to be more important determinant of patient satisfaction than the cognitive evaluation. Periodical assessment of patient satisfaction should be an important component of any programme evaluation exercise.KEY WORDS: Amputation, Patient satisfaction, Programme evaluation, Prosthesis, Quality of care, Rehabilitation  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