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   6817篇
  免费   373篇
  国内免费   23篇
耳鼻咽喉   89篇
儿科学   176篇
妇产科学   155篇
基础医学   1448篇
口腔科学   92篇
临床医学   676篇
内科学   841篇
皮肤病学   518篇
神经病学   498篇
特种医学   398篇
外科学   1118篇
综合类   17篇
一般理论   1篇
预防医学   224篇
眼科学   132篇
药学   463篇
中国医学   4篇
肿瘤学   363篇
  2021年   65篇
  2019年   70篇
  2018年   70篇
  2016年   70篇
  2015年   90篇
  2014年   119篇
  2013年   143篇
  2012年   262篇
  2011年   259篇
  2010年   170篇
  2009年   169篇
  2008年   256篇
  2007年   263篇
  2006年   259篇
  2005年   267篇
  2004年   235篇
  2003年   228篇
  2002年   233篇
  2001年   114篇
  2000年   113篇
  1999年   109篇
  1998年   77篇
  1997年   67篇
  1996年   53篇
  1995年   60篇
  1994年   55篇
  1992年   64篇
  1991年   61篇
  1989年   65篇
  1988年   69篇
  1986年   52篇
  1985年   67篇
  1984年   62篇
  1982年   50篇
  1977年   66篇
  1939年   50篇
  1933年   50篇
  1932年   60篇
  1931年   62篇
  1930年   60篇
  1929年   59篇
  1928年   57篇
  1926年   54篇
  1925年   65篇
  1924年   62篇
  1923年   53篇
  1921年   49篇
  1914年   56篇
  1913年   104篇
  1912年   78篇
排序方式: 共有7213条查询结果,搜索用时 15 毫秒
1.
2.
The assessment of the medical lethality and intent of suicide attempts has been considered an important area of research for those interested in suicide. The current study examined the usefulness of the Risk-Rescue Rating Scale with 109 adolescent suicide attempters and found a restricted range of variability, which, in turn, resulted in poor interrater reliability on a number of items. Results suggest that the Risk-Rescue Rating Scale is of limited usefulness with adolescents, and alternative approaches to assessing lethality and suicidal intent with this age group are discussed.  相似文献   
3.
Eleven patients with refractory rheumatoid arthritis were submitted to a total lymphoid irradiation up to a dose of 20 Gy. A constant improvement of clinical symptoms was observed in four out of the eleven patients already during the treatment and in the other patients not later than two months after. The frequency of attacks decreased and the number of joints involved in the attack was reduced. Morning rigidity and joint swellings decreased. One patient developed joint empyemas 4 and 26 months after the treatment. Four patients died in the meantime. In two patients the cause of death were renal insufficiency and a postoperative cardiogenic shock associated with generalized amyloidosis. The third patient died because of a toxically induced left cardiac decompensation with sepsis that could not be controlled by antibiotic drugs and multiple joint empyemas. The fourth patient developed an abscess after surgical treatment of a Kaposi syndrome. She died three months later from acute left cardiac decompensation. The therapy induced a lymphocytopenia with decrease of T helper lymphocytes and unchanged number of T suppressor lymphocytes. The constant therapy results of total lymphoid irradiation in primary chronic polyarthritis is probably due to this modification in the immune regulation.  相似文献   
4.
Zusammenfassung Das Protamin, Clupeinsulfat, besitzt schon in niedrigsten Konzentrationen die gleichen kolloid-osmotischen und adsorptiven Eigenschaften wie andere höhermolekulare Eiweißkörper. Bis zu 20 Clupeinsulfat verstärken die Kammertätigkeit des hypodynamen Froschherzens. Über 50 Clupeinsulfat bewirken systolischen Kammerstillstand. 0,5–5 Clupeinsulfat verstärken die Azetylcholinwirkung, größere Mengen setzen sie herab, erhöhen aber unter Umständen die Wirkungsdauer. Das Clupeinsulfat geht mit einigen höhermolekularen Eiweißkörpern Verbindungen ein, durch die diese Eiweißkörper eine Änderung in ihrer Löslichkeit, Dispersität und Adsorptionsfähigkeit erfahren.Mit 3 Textabbildungen (11 Einzelbildern).  相似文献   
5.
Patients with moderately severe Parkinson's disease complicated by the adverse effects of chronic levodopa use benefited from the addition of bromocriptine (Parlodel; Sandoz) in doses up to 26 mg daily, which allowed an approximate 30% reduction of levodopa dose. This resulted in a significant decrease in the amount of levodopa side-effects while maintaining or improving the original parkinsonian clinical stage. Increased effectiveness in these patients was not associated with increased dosage beyond 25-30 mg daily. When the doses of bromocriptine were increased slowly, the adverse reactions were minor and usually transient.  相似文献   
6.
What is clusterin?   总被引:1,自引:1,他引:0       下载免费PDF全文
  相似文献   
7.
Fifty peritoneal biopsies (PB) from 35 patients with end-stage renal disease, treated by continuous ambulatory peritoneal dialysis (CAPD) and aged 2 months to 18 years, were examined by light microscopy (n=50) and/or scanning electron microscopy. PB were performed during surgical procedures immediately before the start of, during, or after the cessation of CAPD treatment. PB from 15 children without renal disease undergoing laparatomy were examined similarly. Before the start of CAPD, a scarcity and shortening of the mesothelial microvilli was observed by scanning electron microscopy. During and after CAPD, variable alterations of mesothelium, interstitium and capillaries were found. The mesothelial layer was absent in all 5 PB obtained during episodes of active peritonitis. In patients treated by CAPD for longer than 6 months, mesothelial denudation was observed more frequently (6/11) than in children treated for shorter periods (1/7) (P<0.08). Fibrosis of the peritoneal membrane was present in about 50% of patients during or after the cessation of CAPD without impairment of peritoneal function. No correlation was found between the presence of fibrosis and the frequency of peritonitis or the duration of CAPD treatment.  相似文献   
8.
9.
Objectives: In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false‐positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus. Methods: Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence‐randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure. Results: Of 760 tests run, 18 (2.37%) cases of false‐positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields. Conclusions: AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed.  相似文献   
10.
The elderly account for an ever-increasing proportion of emergency department patients. Demographic data show that the population which is 80 years of age or older will be further increasing in coming years. Due to this fact we sought the reasons of using of the emergency department by elderly patients (≥80 years), admitted by ambulance service, and to analyse the general management of this collective according to a younger comparison group. We used the data from a prospective registry, in which all consecutive patients admitted to the emergency department by ambulance service were included, to process this retrospective analysis. In this registry, diagnosis (in the ICD-10 classification), age, sex, and inpatient/outpatient treatment were documented. In addition further management, intensive care treatment, and outcome during emergency department stay were registered. The patients were stratified by age into two groups (< 80 years; ≥80 years). The observation period lasted from January 1, 2005 to December 31, 2005. During the study 6590 patients were observed of whom 5670 patients (86.0%) were under 80 years (PG<80) and 920 (14.0%) were 80 years of age or older (PG≥80). Comparing inpatient treatment (PG<80: 40.1%; PG≥80: 39.8%) vs outpatient treatment (PG<80: 59.9%; PG≥80: 60.2%) no significant difference between both groups was registered. In comparing the ICD- 10 main diagnosis categories, no relevant difference could be ascertained. By contrast a significantly higher mortality (3.0% vs 1.6%; p≤0.01) in the emergency department was shown within the PG≥80, especially if the diagnosis was myocardial infarction or stroke. The most frequent discharge diagnosis in the PG≥80 was acute myocardial infarction (6.7%). A percutaneous coronary intervention and artificial respiration was less frequently used in the elderly group. Patients beyond 80 years of age nowadays constitute a remarkable proportion of emergency department patients admitted by ambulance service. This group does not differ substantially from younger patients, neither in questions of inpatient or outpatient treatment nor in types of diagnosis. Elderly patients in the emergency department showed a higher mortality. Invasive interventions were less frequently used in this collective in comparison to younger patients. In consideration of the fact that the proportion of elderly will further increase in our population, this analysis may give basis for development of new strategies for the treatment of old patients in emergency departments.  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