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   1129篇
  免费   100篇
  国内免费   3篇
耳鼻咽喉   6篇
儿科学   26篇
妇产科学   23篇
基础医学   131篇
口腔科学   20篇
临床医学   141篇
内科学   184篇
皮肤病学   10篇
神经病学   236篇
特种医学   22篇
外科学   238篇
综合类   13篇
预防医学   41篇
眼科学   41篇
药学   55篇
肿瘤学   45篇
  2023年   7篇
  2022年   11篇
  2021年   26篇
  2020年   16篇
  2019年   22篇
  2018年   40篇
  2017年   25篇
  2016年   25篇
  2015年   23篇
  2014年   35篇
  2013年   35篇
  2012年   67篇
  2011年   68篇
  2010年   39篇
  2009年   33篇
  2008年   61篇
  2007年   70篇
  2006年   69篇
  2005年   52篇
  2004年   66篇
  2003年   46篇
  2002年   48篇
  2001年   27篇
  2000年   35篇
  1999年   26篇
  1998年   13篇
  1997年   13篇
  1996年   11篇
  1995年   13篇
  1994年   13篇
  1993年   8篇
  1992年   19篇
  1991年   27篇
  1990年   22篇
  1989年   10篇
  1988年   13篇
  1987年   13篇
  1986年   10篇
  1985年   11篇
  1984年   4篇
  1983年   6篇
  1981年   4篇
  1979年   5篇
  1977年   5篇
  1975年   3篇
  1974年   3篇
  1969年   3篇
  1968年   3篇
  1966年   4篇
  1964年   3篇
排序方式: 共有1232条查询结果,搜索用时 15 毫秒
71.
72.
Treatment of status epilepticus (SE) has changed little over the last two decades, but the burden of this condition remains important. There is thus a need for alternative pharmacological therapies. Levetiracetam (LEV) has a wide spectrum of action and a favorable pharmacokinetic profile; however, little data exist regarding its use in SE. We identified patients with SE who received LEV, in a database comprising 127 SE episodes. Demographic, clinical and pharmacological data were analyzed, and compared to a control group consisting of 2 subjects from the database for each LEV patient, matched for age and sex. We identified 13 SE episodes occurring in 12 patients (10% of the database). Demographic, etiologic and clinical characteristics and outcome did not differ between the groups. Daily LEV dose ranged between 1,000-6,000 mg. Three patients were probable responders (23%), 1 responded to the treatment but subsequently died (8%), 4 were non-responders (31%, 1 died), and 5 had an undetermined response (38%). LEV may represent a useful alternative in the treatment of SE, particularly if a parenteral form of administration becomes available; to better define its role in this setting, prospective studies are needed.  相似文献   
73.
The visually guided reaching of two patients with bilateral optic ataxia was explored in two experiments. In Experiment 1 simple delayed pointing was compared with immediate pointing. In the immediate pointing task both variable and constant errors increased with target eccentricity. In contrast to the performance of control subjects and contrary to their own beliefs, the patients both showed improved accuracy in the delay condition. This improvement was manifest as a reduction in both pointing variability and in the constant angular error towards the point of fixation. Both angular errors and their improvement with the delay were proportional to target eccentricity. Experiment 2 used a task in which the target was pre-viewed 5s prior to its re-exposure for pointing ('delayed real pointing'). On some trials a conflict was introduced between the present and previous visual information by changing the target's location during the delay. In contrast to control subjects, who ignored the pre-viewed location and aimed directly at the current target, both patients with optic ataxia initiated their movements towards the previously viewed target location. Evidently they relied on off-line information in preference to on-line visual information. In addition, the patients often failed to detect the changes in target location. One of the patients sometimes even guessed incorrectly that the target had changed its location, and her movement trajectory was then more affected by her false belief than by the target's actual location. These findings confirm that posterior parietal lesions severely disrupt direct visuomotor transformations, and suggest that the residual performance is mediated indirectly by expectations or beliefs about target position.  相似文献   
74.
Applications of prism adaptation: a tutorial in theory and method   总被引:6,自引:0,他引:6  
Data and theory from prism adaptation are reviewed for the purpose of identifying control methods in applications of the procedure. Prism exposure evokes three kinds of adaptive or compensatory processes: postural adjustments (visual capture and muscle potentiation), strategic control (including recalibration of target position), and spatial realignment of various sensory-motor reference frames. Muscle potentiation, recalibration, and realignment can all produce prism exposure aftereffects and can all contribute to adaptive performance during prism exposure. Control over these adaptive responses can be achieved by manipulating the locus of asymmetric exercise during exposure (muscle potentiation), the similarity between exposure and post-exposure tasks (calibration), and the timing of visual feedback availability during exposure (realignment).  相似文献   
75.
Pelvic abscesses represent the most frequent complications of colorectal surgery. Percutaneous CT or US guided drainage can be an alternative to surgical drainage that is associated to a significant mortality rate. In the current study results of PAD, performed in 39 patients with pelvic or abdominopelvic abscesses were reviewed in order to evaluate reliability of such procedure. Major part of the collections 33/39 (85%) developed after resective colorectal surgery, and 20/39 (51%) were associated to anastomotic fistula; 22/39 (56%) were poorly defined; 16/39 (41%) were multiloculated; 16/39 (41%) had a stool contamination, 23/39 (58%) were greater than 10 cm; 14/39 (35%) were multiple. Thirty-five patients (89.7%) healed, despite high number of complex abscesses and complete resolution of sepsis was achieved in 5.1 +/- 2.9 days. CT proved to be the most reliable tool in assessing distinctive features of collections as well as in identifying the best route for drainage. Adequate size of the catheter was essential to get an effective drainage. In particular, large sized catheter (> 20 Fr) had to be used to drain collections associated to anastomotic fistulas with stool contamination. In four elderly neoplastic patients with chronic illnesses (10%), only a single small sized catheter could be positioned, because of patients poor compliance and PAD was inaffective. Nevertheless even those patients got a partial resolution of the sepsis and their general conditions markedly improved, so that they were able to underwent successful surgical drainage. In conclusion PAD is a safe and reliable tool that can be employed as an alternative to surgical drainage at least as first measure, even if complex pelvic abscesses are found.  相似文献   
76.
Abnormal glucose homeostasis due to chronic hyperresistinemia   总被引:24,自引:0,他引:24  
Resistin is an adipocyte-secreted protein that circulates at increased levels in obesity. Acute administration of resistin impairs glucose tolerance, but the effects of chronic hyperresistinemia have not been established. Here we describe the generation and characterization of transgenic mice that have high circulating levels of resistin in the setting of normal weight. Fasted blood glucose was higher in resistin-transgenic mice than in their nontransgenic littermates, and glucose tolerance was impaired in the hyperresistinemic mice. Metabolic studies in the setting of a hyperinsulinemic-euglycemic clamp protocol revealed that chronically hyperresistinemic mice have elevated glucose production. This increase in glucose production may be partly explained by increased expression of hepatic phosphoenolpyruvate carboxykinase. Thus, chronic hyperresistinemia impairs normal glucose metabolism.  相似文献   
77.
The aim of this study was to report on the production and the opinions of a video movie on transplantation and organ donation. The video was developed by a medical school student with the help of the students and teachers of a high school for applied arts. For this task, the making of the video was included in the high school program of the participating class. The students were tutored by their photography teacher. The video movie lasts about 50 minutes. Each "scene" lasts no more than 5 minutes, to avoid reducing the attention level. The choice of a nonmedical frame helped to have some moments to digest the technical information and to stress the importance of the patient-physician relationship. The video was employed as a part of small-group lessons in the nephrology course. A semistructured anonymous questionnaire gathered the opinion of 65 students at the end of the lessons. Student satisfaction was high; the median score was the highest (8, range 6 to 10) for the lesson based upon the movie, as compared with the conventional ones on chronic kidney disease or dialysis (7, range 5 to 10). As far as the authors know, this is the first experiment of a multimedia approach, dedicated to medical and nonmedical targets, developed as a graduation thesis in an Italian Medical School. In conclusion, the positive opinions of the students, who highly appreciated the peer-developed message, may suggest implementing such nonconventional educational approaches to support human resources and enthusiasm for kidney transplantation among the new generations.  相似文献   
78.
BACKGROUND: Continuing Education in Medicine (CEM) underlines the importance of updates and information for the health care team. Our aim was to describe the organization and results of a CEM course "educate to organ donation" that involved the nursing team in an educational experience with high school students. The course consists of theory (4 hours; the physician-patient relationship, the educational role of the nurse, the teaching policy, checklist, and results of a school education program) and practice (10 hours; the attendants join the teaching team in the classrooms and in the plenary session). Analysis of anonymous questionnaires performed after the course contained semistructured questions and analog scales. RESULTS: The first acknowledgment came from the Cabinet of Public Health, which gave the maximum number of credits (14 for 14 education hours). Participation: presently 40 nurses, about 40% of those working in the renal unit (over 30 CEM courses are available in the hospital). Satisfaction: Overall score was median 8.5 (6 to 10) including teaching materials = 8 (4 to 10). Among the theoretical part, the lesson on patient-physician relationship obtained the highest score. The main drawback was the shortness of the practical part. The classroom meeting achieved a median score of 9.5 (7 to 10), the general session = 9 (5 to 10). All but one nurse registered for an "advanced" course, giving more time to the practical part (20 hours). CONCLUSION: CEM may represent an important way to deliver education on transplant-related issues to patients and to the general population.  相似文献   
79.
OBJECTIVE: To confirm the increase in non-transferrin bound iron (NTBI) after packed red cell (PRC) transfusion and to evaluate the association with increased oxidative stress in preterm infants. METHOD: Twenty healthy preterm infants (gestational age 28.2 (2.2) weeks; birth weight 1047 (230) g), who required blood transfusion for anaemia of prematurity were prospectively studied. Serum concentrations of NTBI, total hydroperoxides (TH), and protein SH groups, and plasma total radical trapping antioxidant capability (TAC) were measured within three hours before and after PRC transfusion. The infants were transfused with 38.6 (23) ml PRCs over 5.8 (1.0) hours, at a mean age of 43.3 (25.1) days. RESULTS: After PRC transfusion, haemoglobin concentration increased from 9.2 (1.1) to 14.6 (1.5) g/l. Mean plasma NTBI concentration after transfusion was significantly higher (0.43 (0.45) v 2.03 (1.31) micromol/l; p = 0.001), while plasma concentrations of TH (212.3 (42.2) v 214.7 (66.3) Carr units/l) and protein SH groups (317.5 (38.8) v 353.8 (57.4) micromol/), and TAC (256.3 (36.1) v 267.1 (42.4) micromol HClO/ml) remained unchanged. CONCLUSION: For three hours after PRC transfusion, plasma NTBI is significantly increased in preterm infants, but this is not associated with significant changes in oxidative stress.  相似文献   
80.
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