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   688篇
  免费   61篇
  国内免费   3篇
耳鼻咽喉   3篇
儿科学   41篇
妇产科学   6篇
基础医学   94篇
口腔科学   18篇
临床医学   124篇
内科学   182篇
皮肤病学   14篇
神经病学   7篇
特种医学   71篇
外科学   29篇
综合类   26篇
一般理论   2篇
预防医学   39篇
眼科学   1篇
药学   45篇
肿瘤学   50篇
  2022年   3篇
  2021年   6篇
  2019年   6篇
  2018年   13篇
  2017年   7篇
  2016年   9篇
  2015年   8篇
  2014年   13篇
  2013年   19篇
  2012年   25篇
  2011年   29篇
  2010年   17篇
  2009年   30篇
  2008年   34篇
  2007年   30篇
  2006年   37篇
  2005年   34篇
  2004年   30篇
  2003年   28篇
  2002年   22篇
  2001年   18篇
  2000年   29篇
  1999年   17篇
  1998年   21篇
  1997年   30篇
  1996年   20篇
  1995年   15篇
  1994年   8篇
  1993年   10篇
  1992年   15篇
  1991年   6篇
  1990年   7篇
  1989年   15篇
  1988年   8篇
  1987年   13篇
  1986年   11篇
  1985年   27篇
  1984年   10篇
  1983年   9篇
  1982年   12篇
  1981年   9篇
  1980年   8篇
  1979年   5篇
  1978年   6篇
  1977年   4篇
  1976年   2篇
  1975年   5篇
  1973年   2篇
  1972年   3篇
  1891年   1篇
排序方式: 共有752条查询结果,搜索用时 15 毫秒
81.
Nosocomial pneumonia remains a common problem and is the leading cause of death among patients with nosocomial infection. However, the initial empiric therapy of nosocomial pneumonia is directed at the leading organisms common to all patients, and for many patients monotherapy is adequate for at least 48 hours, at which time the microbiological results of appropriate diagnostic procedures should be known and the treatment can be focused. The currently available antimicrobial agents such as third- and fourth-generation cephalosporins, piperacillin plus tazobactam, carbapenems, and some fluoroquinolones are highly active and bactericidal. They should be used in consideration of current pharmacodynamic knowledge, which will lead to convincing clinical results. Combination of antibiotics is necessary only in specific situations or for the amelioration of special pathogens, such as Pseudomonas aeruginosa, Acinetobacter spp., and against mixed aerobic and anaerobic infections.  相似文献   
82.
Kunicki  TJ; Pidard  D; Rosa  JP; Nurden  AT 《Blood》1981,58(2):268-278
Triton X-100 soluble proteins from 125I-labeled human platelets were studied by crossed immunoelectrophoresis employing a multispecific rabbit antibody raised against whole normal platelets. Emphasis was placed upon an analysis of immunoprecipitates containing 125I-labeled major membrane glycoproteins, and in particular, a prominent immunoprecipitate containing a glycoprotein antigen (s) previously designated as protein 16. SDS-polyacrylamide gel electrophoresis of protein 16 precipitated by a monospecific alloantibody. IgG L . . . , confirmed the presence of both glycoproteins IIb and IIIa. 125I-IgG L . . . , at concentration below that capable of precipitating protein 16 by itself, bound specifically to the precipitate containing protein 16 produced by the multispecific rabbit antibody. No other precipitates formed by the rabbit antibody contained either glycoprotein IIb or IIIa. When platelet proteins, incubated with optimum concentrations of ethylenediamine tetraacetic acid (EDTA) or ethyleneglycol bis (B- aminoethylether) NN1-tetraacetic acid (EGTA), were electrophoresed against the rabbit antibody, previously unobserved immunoprecipitates that contained either free glycoprotein IIb or free glycoprotein IIIa were detected. Upon readdition of excess Ca++, but not Mg++, to the same protein samples, a single immunoprecipitate containing both glycoproteins was once again observed. It is thus demonstrated that glycoproteins IIb and IIIa can form Ca++-dependent complexes (protein 16) in Triton X-100 extracts of normal platelets. The potential significance of the reversible association of these glycoproteins to normal platelet function is discussed.  相似文献   
83.
Surface shield: device to reduce personnel radiation exposure   总被引:2,自引:0,他引:2  
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed.  相似文献   
84.
85.
Pulmonary schistosomiasis resembling acute pulmonary tuberculosis.   总被引:1,自引:0,他引:1  
Pulmonary involvement of schistosomiasis is usually characterized by a miliary mottling or diffuse nodular infiltrates. In most cases, pulmonary involvement is associated with an apparent clinical involvement of other organs. This report describes a 35 yr old patient who developed a cavity, a parenchymatous infiltrate and hilar adenopathy in association with pulmonary schistosomiasis. Schistosoma eggs were demonstrated in transbronchial biopsies from the lung. Pulmonary involvement of schistosomiasis is reviewed and atypical features are discussed, which may lead to diagnostic difficulties, particularly compared to tuberculosis.  相似文献   
86.
Patients with multiresistant tuberculosis (TB) and patients with intolerance of first line antituberculosis drugs present a major treatment problem. Sparfloxacin is highly active against mycobacteria, but the use is restricted by side effects and the contribution to antituberculosis therapy is unclear. A prospective study has therefore been performed to analyse the efficacy and tolerability of sparfloxacin in cases of resistant TB or intolerance of first line therapy. Between April 1993 and April 1999, 30 TB patients (28 with pulmonary TB and two with lymph node TB) were treated with combinations of sparfloxacin and at least two other drugs at the Chest Hospital Heckeshorn, Berlin. Sixteen patients were infected by resistant mycobacteria (one single drug resistance (SDR), one polyresistance, and 14 multidrug resistances (MDR); 14 males (age range 23-53 yrs), 2 females (68-74 yrs)). Twelve patients (11 males, one female, 27-80 yrs) had not tolerated first line antituberculosis drugs. Two additional male patients had continuous proof of Mycobacterium tuberculosis in sputum without resistance during therapy The duration of sparfloxacin therapy during hospitalization ranged 2.5-4 months. Twenty-five patients completed therapy and were cured according to this study's definition. Although sparfloxacin was generally well tolerated, five mild phototoxic reactions and six moderate prolongations of the electrocardiographic QT-interval (30-40 ms compared to baseline < or = 450 ms) were registered without clinical symptoms in the patient group. In summary, sparfloxacin proved an effective and safe alternative antituberculosis drug for complicated tuberculosis.  相似文献   
87.
BACKGROUND: Different protocols have been used for narrowband ultraviolet B (UVB) therapy, commonly used in the treatment of psoriasis; however, more effective and reliable protocols are still required. OBJECTIVE: The aim of this study was to compare the weekly and daily dose increment protocols of narrowband UVB phototherapy in psoriasis patients. METHODS: Thirty patients with plaque psoriasis underwent narrowband UVB treatment three times a week and 15 patients selected consecutively among these patients underwent a weekly (once in three treatments) dose increment whereas the remaining 15 patients underwent a daily dose increment. Patients were monitored for 10 weeks and evaluated by the Psoriasis Area Severity Index (PASI). RESULTS: When the two groups were evaluated according to median PASI scores prior to the treatment and during 10 weeks of treatment, there was no statistically significant difference between the groups (P > 0.05). During the treatment lasting for 10 weeks, four patients in the group with a weekly dose increment and three patients in the group with a daily dose increment recovered and no statistically significant difference was detected between the groups (P > 0.05). The groups were also evaluated according to the median cumulative dose. The median cumulative dose was higher in the group with a daily dose increment and the difference between the groups was statistically significant (P = 0.002). CONCLUSION: The application of daily dose increments was no better than that of weekly dose increments in narrowband UVB treatment for psoriasis. Therefore, although our results may need to be supported by large-series studies, we conclude that application of weekly dose increments with a lower cumulative dose having the same efficacy is preferred in narrowband UVB treatment of psoriasis.  相似文献   
88.
The here described investigations show correspondingly that the administration of isoniazid, rifampicin and pyrazinamide in a fixed combination of the administration of the individual substances is bioequivalent under pharmacokinetic aspects. Further investigations on large populations of patients must, however, still confirm whether or not the advantages of the fix combination striven for or theoretically to be expected can be proved in practice.  相似文献   
89.
A. Lubasch  H. Lode 《Der Internist》2000,287(1):494-497
Die Reisediarrh? ist die h?ufigste Form der infekti?sen Diarrh? des Erwachsenen. Abh?ngig von den angestrebten Reisezielen und dem allgemeinen Gesundheitszustand des Reisenden sollten diesem entsprechende Empfehlungen hinsichtlich Prophylaxe und Therapie mit auf den Weg gegeben werden.  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