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   2039篇
  免费   147篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   46篇
妇产科学   35篇
基础医学   301篇
口腔科学   44篇
临床医学   248篇
内科学   427篇
皮肤病学   44篇
神经病学   227篇
特种医学   50篇
外科学   215篇
综合类   13篇
一般理论   1篇
预防医学   251篇
眼科学   16篇
药学   179篇
中国医学   4篇
肿瘤学   86篇
  2023年   13篇
  2022年   23篇
  2021年   34篇
  2020年   39篇
  2019年   53篇
  2018年   62篇
  2017年   70篇
  2016年   57篇
  2015年   58篇
  2014年   51篇
  2013年   91篇
  2012年   141篇
  2011年   124篇
  2010年   74篇
  2009年   63篇
  2008年   119篇
  2007年   137篇
  2006年   120篇
  2005年   116篇
  2004年   105篇
  2003年   87篇
  2002年   69篇
  2001年   24篇
  2000年   30篇
  1999年   21篇
  1998年   19篇
  1997年   21篇
  1996年   18篇
  1995年   16篇
  1994年   18篇
  1993年   15篇
  1992年   25篇
  1991年   25篇
  1990年   26篇
  1989年   18篇
  1988年   20篇
  1987年   21篇
  1986年   19篇
  1985年   23篇
  1984年   11篇
  1983年   7篇
  1982年   5篇
  1981年   11篇
  1979年   6篇
  1978年   14篇
  1977年   5篇
  1974年   6篇
  1973年   7篇
  1970年   8篇
  1966年   11篇
排序方式: 共有2189条查询结果,搜索用时 359 毫秒
1.
Wound pain is a serious problem for elderly patients suffering from chronic leg ulcers, and it may lead to reduced wound healing rates and reduced quality of life. Biatain-Ibu Non-adhesive (Coloplast A/S), a new pain-reducing moist wound healing dressing containing ibuprofen was tested for pain reduction, safety, and efficacy on 10+2 patients in a single-blinded crossover study against Biatain Non-adhesive (Coloplast A/S). Pain was measured with a Numeric Box Scale before, during, and after dressing change. Quality of life was measured using the World Health Organization-5 Well-Being Index. Dressing moist wound healing properties such as absorption capacity and leakage were tested together with assessment of wound exudate and blood plasma content of ibuprofen. Use of the Biatain-Ibu foam dressing correlated with a decrease in pain intensity scores from 7 in the run-in period to approximately 2.5 in the Biatain-Ibu treatment phase. Quality of life measures were improved which together with the reduced pain could contribute to faster wound healing. The moist wound healing properties of Biatain-Ibu were similar to that of the Biatain Non-adhesive and ulcer size was reduced by 24% during the treatment period. Neither side effects nor systemic plasma concentrations of ibuprofen were observed. These data indicate that Biatain-Ibu could reduce persistent and temporary wound pain, increase Quality of life, was found safe to use, and had excellent moist wound healing properties.  相似文献   
2.
Bone turnover before and after withdrawal of estrogen/gestagen treatment was studied in a randomized trial with 110 healthy female volunteers, who had passed a natural menopause 6 months to 3 years before the start of the study. Urinary excretion of intravenously injected 99m-technetium diphosphonate was measured as an index of bone turnover; plasma bone Gla protein and serum alkaline phosphatase were measured as indices of bone formation; and fasting urinary excretion of hydroxyproline and calcium were measured as estimates of bone resorption. During 2 years of hormone treatment, all variables decreased highly significantly (p less than 0.001) to a constant low level. Three months after withdrawal all variables increased highly significantly (p less than 0.001) towards, but not above, pretreatment and placebo levels. We conclude that withdrawal of estrogen/gestagen replacement therapy in postmenopausal women increases bone turnover, but not in excess of pretreatment values. This indicates that bone loss (after withdrawal) is similar to that seen in the placebo group and that a rebound phenomenon is unlikely.  相似文献   
3.
Background and Purpose . Patients with multiple sclerosis (MS) tend to have movement difficulties, and the effect of physiotherapy for this group of patients has been subjected to limited systematic research. In the present study physiotherapy based on the Bobath concept, applied to MS patients with balance and gait problems, was evaluated. The ability of different functional tests to demonstrate change was evaluated. Method . A single‐subject experimental study design with ABAA phases was used, and two patients with relapsing–remitting MS in stable phase were treated. Tests were performed 12 times, three at each phase: A (at baseline); B (during treatment); A (immediately after treatment); and A (after two months). The key feature of treatment was facilitation of postural activity and selective control of movement. Several performance and self‐report measures and interviews were used. Results . After intervention, improved balance was shown by the Berg Balance Scale (BBS) in both patients, and improved quality of gait was indicated by the Rivermead Visual Gait Assessment (RVGA). The patients also reported improved balance and gait function in the interviews and scored their condition as ‘much improved’. Gait parameters, recorded by an electronic walkway, changed, but differently in the two patients. Among the physical performance tests the BBS and the RVGA demonstrated the highest change, while no or minimal change was demonstrated by the Rivermead Mobility Index (RMI) and Ratings of Perceived Exertion (RPE). Conclusion . The findings indicate that balance and gait can be improved after physiotherapy based on the Bobath concept, but this should be further evaluated in larger controlled trials of patients with MS. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
4.
Protein synthesis in skeletal muscle is known to decrease during contractions but the underlying regulatory mechanisms are unknown. Here, the effect of exercise on skeletal muscle eukaryotic elongation factor 2 (eEF2) phosphorylation, a key component in protein translation machinery, was examined. Eight healthy men exercised on a cycle ergometer at a workload eliciting ∼67% peak pulmonary oxygen consumption     with skeletal muscle biopsies taken from the vastus lateralis muscle at rest as well as after 1, 10, 30, 60 and 90 min of exercise. In response to exercise, there was a rapid (i.e. < 1 min) 5- to 7-fold increase in eEF2 phosphorylation at Thr56 that was sustained for 90 min of continuous exercise. The in vitro activity of skeletal muscle eEF2 kinase was not altered by exercise indicating that the increased activity of eEF2 kinase to eEF2 is not mediated by covalent mechanisms. In support of this, the increase in AMPK activity was temporally unrelated to eEF2 phosphorylation. However, skeletal muscle eEF2 kinase was potently activated by Ca2+–calmodulin in vitro , suggesting that the higher eEF2 phosphorylation in working skeletal muscle is mediated by allosteric activation of eEF2 kinase by Ca2+ signalling via calmodulin. Given that eEF2 phosphorylation inhibits eEF2 activity and mRNA translation, these findings suggest that the inhibition of protein synthesis in contracting skeletal muscle is due to the Ca2+-induced stimulation of eEF2 kinase.  相似文献   
5.
 Lactate/H+ transport kinetics were determined by means of the pH-sensitive probe BCECF in sarcolemmal giant vesicles, obtained from rat skeletal muscle, and related to variations in lactate/H+ transport capacity. Vesicle preparations were made from red and white muscles, mixed muscles, denervated muscles, muscles of old rats and rats that had been subjected to high-intensity training, endurance training, repeated exposure to hypoxia, and hypothyroid or hyperthyroid treatments. The lactate/H+ transport capacity of red muscles was greater than that of white muscles, and this difference was associated with a higher maximal transport rate (V max) in red muscles, whereas the K m was similar in the two muscle types. High-intensity training and hyperthyroidism increased the lactate/H+ transport capacity by enhancing V max without affecting K m. Similarly, a reduced transport capacity with old age and hypothyroidism was due to a decrease in V max. The denervation-induced decline in lactate/H+ transport capacity resulted from both an increased K m and a reduced V max. The present data show that muscle type differences and most changes in the lactate/H+ transport capacity are mediated by modifications in V max, which is expected to represent the number of membrane transporter molecules. K m is unaffected by most treatments and appears to be independent of fibre type. Received: 10 February 1998 / Received after revision: 21 April 1998 / Accepted: 24 April 1998  相似文献   
6.
7.
8.
Conservative treatment for acute rupture of the Achilles tendon   总被引:1,自引:0,他引:1  
Summary Sixty-six patients with acute ruptures of the Achilles tendon were treated by immobilisation in a plaster cast for 12 weeks. Fifty-seven were followed up for a mean time of 70 months. Four re-ruptures occurred shortly after the initial treatment. Most patients had no or only slight complaints, three had moderate and one severe, problems. The activity level dropped slightly from 5.3 to 5.03 (Tegner score). The results are satisfactory with a low complication rate. The method is an alternative to operative repair, especially in patients declining operation and in those in whom operation or anaesthesia is contraindicated.
Résumé Soixante-six malades ont fait l'objet d'une étude à long terme concernant le traitement non-chirurgical des ruptures aiguës du tendon d'Achille. Le recul moyen était de 70 mois. Les patients avaient été immobilisés dans un plâtre pendant 12 semaines. 4 ruptures itératives survinrent précocément (6%). La plupart des malades n'avaient pas ou peu de séquelles, trois seulement se plaignaient d'une gêne modérée et 1 d'une gêne importante. Le niveau d'activité avait légérement diminué, de 5.3 à 5.03 (selon le score de Tegner). Les résultats paraissaient satisfaisants dans l'ensemble, avec une taux peu élevé de ruptures itératives ou d'autres complications. La méthode constitue une alternative valable au traitement chirurgical, notamment chez les sujets qui ne veulent pas être opérés ou chez ceux qui présentent des contrindications à l'anesthésie ou à la chirurgie.
  相似文献   
9.
Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.  相似文献   
10.
Distraction effects on muscle: Leg lengthening studied in rabbits   总被引:1,自引:0,他引:1  
We investigaed changes in the anterior tibial muscle during lengthening of the lower leg in rabbits. In 37 rabbits, an osteotomy of the right middle tibia was performed and was fixed by a unilateral external fixator. The rabbits were randomized into 6 groups. In groups 1, 2, and 3 the tibiae were distracted 0.5 mm/day. In groups 1 and 2, the rabbits were killed after 14 and 28 days of distraction, respectively, and in group 3 after 28 days of distraction, followed by 14 days of rest. Groups 1a, 2a, and 3a served as controls. They were treated similarly as groups 1, 2, and 3, but no distracton was performed. Proliferating cell nuclei were labeled with 5-bromo-2-deoxyuridine and were identified by immunohistochemical staining. The weight of the muscle was measured. During bone lengthening the muscle showed signs of growth, as indicated by increasing weight and number of proliferating cell nuclei. This was observed only during lengthening and it ceased when the lengthening was stopped.  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