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   1493篇
  免费   188篇
  国内免费   10篇
耳鼻咽喉   15篇
儿科学   98篇
妇产科学   29篇
基础医学   145篇
口腔科学   46篇
临床医学   215篇
内科学   316篇
皮肤病学   15篇
神经病学   132篇
特种医学   172篇
外科学   193篇
综合类   44篇
预防医学   111篇
眼科学   3篇
药学   81篇
中国医学   6篇
肿瘤学   70篇
  2023年   5篇
  2022年   9篇
  2021年   17篇
  2020年   16篇
  2019年   18篇
  2018年   49篇
  2017年   51篇
  2016年   40篇
  2015年   42篇
  2014年   47篇
  2013年   72篇
  2012年   47篇
  2011年   43篇
  2010年   77篇
  2009年   67篇
  2008年   63篇
  2007年   57篇
  2006年   53篇
  2005年   41篇
  2004年   36篇
  2003年   39篇
  2002年   28篇
  2001年   38篇
  2000年   39篇
  1999年   35篇
  1998年   64篇
  1997年   60篇
  1996年   61篇
  1995年   51篇
  1994年   33篇
  1993年   42篇
  1992年   23篇
  1991年   28篇
  1990年   29篇
  1989年   31篇
  1988年   32篇
  1987年   38篇
  1986年   19篇
  1985年   18篇
  1984年   20篇
  1983年   21篇
  1982年   10篇
  1981年   21篇
  1980年   8篇
  1979年   4篇
  1978年   5篇
  1977年   14篇
  1976年   9篇
  1975年   6篇
  1971年   4篇
排序方式: 共有1691条查询结果,搜索用时 546 毫秒
81.
A phase I clinical trial was initiated to treat patients with stage IV B-derived chronic lymphocytic leukemia (CLL) with the IgG2a murine monoclonal antibody T101. This antibody binds to a 65,000-mol wt (T65) antigen found on normal T lymphocytes, malignant T lymphocytes, and B- derived CLL cells. All of the patients had a histologically confirmed diagnosis of advanced B-derived CLL and were refractory to standard therapy, and more than 50% of their leukemia cells reacted with the T101 antibody in vitro. The patients received T101 antibody two times per week, over two to 50 hours by intravenous administration in 100 mL of normal saline containing 5% human albumin. Twelve patients were treated with a fixed dosage of 1, 10, 50, or 100 mg, and one patient was treated with 140 mg of antibody. It was demonstrated that patients given two-hour infusions of 50 mg developed pulmonary toxicity, with shortness of breath and chest tightness. This toxicity was eliminated when infusions of 50 or 100 mg of T101 were prolonged to 50 hours. All dose levels caused a rapid but transient decrease in circulating leukemia cell counts. In vivo binding to circulating and bone marrow leukemia cells was demonstrated at all dose levels with increased binding at higher dosages. Antimurine antibody responses were not demonstrated in any patients at any time during treatment. Circulating free murine antibody was demonstrated in the serum of only the two patients treated with 100 mg of antibody as a 50-hour infusion and the patient treated with 140 mg of antibody over 30 hours. Antigenic modulation was demonstrated in patients treated at all dose levels but was particularly apparent in patients treated with prolonged infusions of 50 and 100 mg of antibody. We were also able to demonstrate antigenic modulation in lymph node cells, which strongly suggests in vivo labeling of these cells. Overall, T101 antibody alone appears to have a very limited therapeutic value for patients with CLL. The observations of in vivo labeling of tumor cells, antigenic modulation, antibody pharmacokinetics, toxicity, and antimurine antibody formation may be used in the future for more effective therapy when drugs or toxins are conjugated to the antibody.  相似文献   
82.
The Randomized Endo‐vein Graft Prospective (REGROUP) trial ( ClinicalTrials.gov  NCT01850082) is a randomized, intent‐to‐treat, 2‐arm, parallel‐design, multicenter study funded by the Cooperative Studies Program (CSP No. 588) of the US Department of Veterans Affairs. Cardiac surgeons at 16 Veterans Affairs (VA) medical centers with technical expertise in performing both endoscopic vein harvesting (EVH) and open vein harvesting (OVH) were recruited as the REGROUP surgeon participants. Subjects requiring elective or urgent coronary artery bypass grafting using cardiopulmonary bypass with use of ≥1 saphenous vein graft will be screened for enrollment using pre‐established inclusion/exclusion criteria. Enrolled subjects (planned N = 1150) will be randomized to 1 of the 2 arms (EVH or OVH) after an experienced vein harvester has been assigned. The primary outcomes measure is the rate of major adverse cardiac events (MACE), including death, myocardial infarction, or revascularization. Subject assessments will be performed at multiple times, including at baseline, intraoperatively, postoperatively, and at discharge (or 30 days after surgery, if still hospitalized). Assessment of leg‐wound complications will be completed at 6 weeks after surgery. Telephone follow‐ups will occur at 3‐month intervals after surgery until the participating sites are decommissioned after the trial's completion (approximately 4.5 years after the full study startup). To assess long‐term outcomes, centralized follow‐up of MACE for 2 additional years will be centrally performed using VA and non‐VA clinical and administrative databases. The primary MACE outcome will be compared between the 2 arms, EVH and OVH, at the end of the trial duration.  相似文献   
83.
84.
85.
86.
87.
Objectives: To screen for potentially underreported behavioral changes in patients with idiopathic Parkinson's disease (PD) pre‐ and post‐deep brain stimulation (DBS), a retrospective data base review was performed. Methods: In total, 113 patients who underwent unilateral or bilateral DBS at the University of Florida in either subthalamic nucleus or globus pallidus internus for PD were screened for behavioral issues by asking about the presence or absence of seven neuropsychiatric symptoms (panic, fear, paranoia, anger, suicidal flashes, crying, and laughing). Results: There was a high prevalence of fear (16.3%), panic (14.0%), and anger (11.6%) at baseline in this cohort. In the first six months following DBS implantation, anger (32.6%), fear (26.7%), and uncontrollable crying (26.7%) were the most frequent symptoms reported. Those symptoms also were present following six months of DBS surgery (30.2%, 29.1%, and 19.8%, respectively). New uncontrollable crying occurred more in the acute postoperative stage (less than or equal to six months) (p= 0.033), while new anger occurred more in the chronic postoperative stage (greater than six months) (p= 0.017). The frequency of uncontrollable laughing significantly increased with bilateral DBS (p= 0.033). Conclusions: Many of the neuropsychiatric issues were identified at preoperative baseline and their overall occurrence was more than expected. There was a potential for worsening of these issues post‐DBS. There were subtle differences in time course, and in unilateral vs. bilateral implantations. Clinicians should be aware of these potential behavioral issues that may emerge following DBS therapy, and should consider including screening questions in preoperative and postoperative interviews. Standardized scales may miss the presence or absence of these clinically relevant issues.  相似文献   
88.
In a cross-sectional study of aggression, and adaptive and maladaptive behaviour in 128 subjects with Down's syndrome (DS), 29 of whom had dementia, the current authors found that the presence of dementia was not predictive of aggression or maladaptive behaviour. However, the level of adaptive behaviour was shown to be lower in subjects with dementia, and in those with lower levels of cognitive functioning, as measured on a rating instrument, the Test for Severe Impairment. Although the presence of aggressive behaviours is not higher in subjects with dementia and DS on cross-sectional review, it remains to be seen whether aggression will increase in individual cases with the onset or progression of dementia. The decline in adaptive behaviour shown in the present study confirms the findings of previous studies and indicates a direction for service development for persons with the dual diagnosis of dementia and DS.  相似文献   
89.
Background: The incidence of obesity is rising, and an increasing number of obese patients are admitted to surgical intensive care units (SICUs). However, it is not clear whether obesity is an independent risk factor for increased morbidity and mortality in SICU patients. We examined the effect of obesity on morbidity and mortality in patients admitted to the SICU in this study. Method: We reviewed prospectively acquired SICU data in normal and obese patients with an SICU length of stay >24 hours. Comparability of the groups was assessed using a χ2 test or Fisher exact test, as appropriate, for categorical variables and analysis of variance (ANOVA) or the Kruskal‐Wallis test, as appropriate, for continuous variables. Results: Of the 1792 consecutive patients evaluated, 711 had a normal body mass index (BMI), and 993 were either preobese or obese. There was no statistically significant difference across the 5 BMI groups with respect to any of the 3 comorbidity indices (Acute Physiology and Chronic Health Evaluation III [APACHE III], Simplified Acute Physiology Score, or Multiple Organ Dysfunction Score). There was no statistically significant difference in the intensive care unit (ICU) length of stay and hospital length of stay or time‐to‐ICU mortality (log‐rank test P = .054) among the 5 BMI groups. A Cox regression analysis and backward elimination algorithm selected APACHE III to be the most important explanatory variable for survival time. Conclusion: Obesity does not affect the mortality of patients admitted to the SICU. We conclude that obesity cannot be used as an independent predictive mortality outcome variable in patients admitted to the SICU.  相似文献   
90.
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