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   11567篇
  免费   1001篇
  国内免费   60篇
耳鼻咽喉   29篇
儿科学   314篇
妇产科学   144篇
基础医学   211篇
口腔科学   171篇
临床医学   5934篇
内科学   1132篇
皮肤病学   85篇
神经病学   264篇
特种医学   233篇
外国民族医学   1篇
外科学   724篇
综合类   1002篇
一般理论   4篇
预防医学   1591篇
眼科学   42篇
药学   503篇
  48篇
中国医学   141篇
肿瘤学   55篇
  2024年   21篇
  2023年   362篇
  2022年   299篇
  2021年   563篇
  2020年   724篇
  2019年   584篇
  2018年   490篇
  2017年   496篇
  2016年   500篇
  2015年   416篇
  2014年   756篇
  2013年   1066篇
  2012年   622篇
  2011年   593篇
  2010年   556篇
  2009年   558篇
  2008年   466篇
  2007年   494篇
  2006年   488篇
  2005年   363篇
  2004年   315篇
  2003年   281篇
  2002年   175篇
  2001年   173篇
  2000年   176篇
  1999年   184篇
  1998年   138篇
  1997年   130篇
  1996年   114篇
  1995年   140篇
  1994年   85篇
  1993年   22篇
  1992年   18篇
  1991年   17篇
  1990年   16篇
  1989年   15篇
  1988年   9篇
  1987年   5篇
  1986年   8篇
  1985年   44篇
  1984年   37篇
  1983年   23篇
  1982年   27篇
  1981年   14篇
  1980年   39篇
  1978年   2篇
  1977年   2篇
  1974年   1篇
  1973年   1篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
The use of anaesthesiologists in prehospital emergency care is controversial. We wanted to assess the impact of an anaesthesiologist and a short time interval from acceptance of a mission to take–off at survival rates in a rural/urban emergency medical service. Prospectively registered data for 991 consecutive patients through a 12–month period were retrospectively evaluated by an independent foreign expert. Of all primary missions, 3.3% were considered probably lifesaving from site of injury to receiving hospital. Of these, the lifesaving result in 50% were dependent on both the qualifications of the anaesthesiologist and a short response time. Survival from hospital admission to discharge was 44%. All patients were discharged to their own homes, able to live a fully functional life. The consistent use of anaesthesiologists compared to less qualified personnel and the maintaining of response times below presently required minima doubles the potential for lives saved in services comparable to the one studied.  相似文献   
52.
53.
Objectives
To explore medical students' use of computer tutorials embedded in a busy clinical setting; to demonstrate that such tutorials can increase knowledge gain over and above that attributable to the clinical rotation itself.
Methods
Six tutorials were installed on a computer placed in a central area in an emergency department. Each tutorial was made up of between 33 and 85 screens of information that include text, graphics, animations, and questions. They were designed to be brief (10 minutes), focused, interactive, and immediately relevant. The authors evaluated the intervention using quantitative research methods, including usage tracking, surveys of faculty and students, and a randomized pretest-posttest study.
Results
Over 46 weeks, 95 medical students used the tutorials 544 times, for an overall average of 1.7 times a day. The median time spent on completed tutorials was 11 minutes (average [SD], 14 [±12] minutes). Seventy-four students completed the randomized study. They completed 65% of the assigned tutorials, resulting in improved examination scores compared with the control (effect size, 0.39; 95% confidence interval = 0.15 to 0.62). Students were positively disposed to the tutorials, ranking them as "valuable." Fifty-four percent preferred the tutorials to small group teaching sessions with a preceptor. The faculty was also positive about the tutorials, although they did not appear to integrate the tutorials directly into their teaching.
Conclusions
Medical students on rotation in a busy clinical setting can and will use appropriately presented computer tutorials. The tutorials are effective in raising examination scores.  相似文献   
54.
55.
Droperidol (DROP) is used in the emergency department (ED) for sedation, analgesia, and its antiemetic effect. Its ED safety profile has not yet been reported in patients (pts). OBJECTIVES: To document the use of DROP in high-risk pts (those with head injury, alcohol or cocaine intoxication, and/or remote or recent seizures), and to determine the number of serious and minor adverse events (AEs)-seizures, hypotension, extrapyramidal side effects (EPSEs)-after DROP. METHODS: The ED database (EmSTAT) was queried to determine who received intramuscular or intravenous DROP in the ED in 1998; further chart review was done if the patient was considered high risk for or had experienced an AE. Multiple regression analysis using a random-effects model determined the significance of each variable in the occurrence of AEs. RESULTS: 2,468 patients (aged 20 months to 98 years; 112 < or =17 years; 141 > or =66 years) received DROP for agitation (n = 1,357), pain (1,135), anxiety (99), vomiting (173), or other reasons (50). There were 945 pts considered high risk; 933 charts were reviewed (DROP mean dose 4.1 +/- 2.0 mg); of these, 50 patient visits did not meet the criteria for high risk. There were 622 pts with head trauma (401 with alcohol use), including 47 with computed tomography (CT) scans positive for brain injury, 64 with cocaine use, and 197 with recent or remote seizures (137 with alcohol use). Minor AEs such as transient hypotension occurred in 96 pts after DROP (73 with alcohol use); 20 received intravenous fluids, while an additional 28 pts (8 with alcohol use) received rescue medications for EPSEs. Six possible serious AEs occurred in pts with serious comorbidities; 2 cases of respiratory depression, 3 post-DROP seizures, and 1 cardiac arrest (resuscitated) 11 hours after DROP in a cocaine-intoxicated pt (normal QT interval). There was no significant difference among high-risk groups in the occurrence of AEs. CONCLUSIONS: The vast majority of pts who received DROP in the ED did not experience an AE. A few serious AEs were noted following DROP in patients with serious comorbidities; it is not clear that DROP was causative.  相似文献   
56.
Objective: To determine which characteristics of older patients who use a hospital ED are associated with repeat visits during the 90 days following the index visit.
Methods: The study was conducted in the ED of a 400-bed university-affiliated acute care community hospital in Montreal. Patients aged ≥75 years who visited the ED between 08:00 and and 16:00 on a convenience sample of days over an 8-week period (July and August 1994) were assessed using a questionnaire, physical and cognitive status instruments, and a functional problem checklist. The hospital's administrative database was used to identify repeat visits during the 90 days following the ED visit. The representativeness of the sample was assessed by analyses of ED visits made by 4,466 persons aged ≥65 years during a 12-month period (September 1993 to August 1994) using the hospital's administrative database.
Results: 256 patients aged ≥75 years visited the ED during the study period and 167 were assessed. Of these, 54 (32%) were admitted to the hospital. Among the 113 patients released from the ED, 27 (24%) made repeat visits during the next 90 days. In univariate analyses, repeat visits were significantly associated with the number of functional problems, cognitive impairment, and previous ED visits. In multiple logistic regression, male gender, living alone, and number of functional problems were independent predictors of repeat visits. In the administrative data analyses, nighttime arrival to the ED for the index visit was significantly associated with repeat visits.
Conclusions: Self-reported risk factors can help to identify a group of elders likely to make repeated ED visits; the development of a screening instrument incorporating questions on these problems and implementation of appropriate interventions might improve these patients' quality of life and reduce the demand for further ED care in this age group.  相似文献   
57.
End-tidal Carbon Dioxide Monitoring during Procedural Sedation   总被引:2,自引:0,他引:2  
OBJECTIVE: To prospectively determine whether end-tidal carbon dioxide (ETCO2) monitors can detect respiratory depression (RD) and the level of sedation in emergency department (ED) patients undergoing procedural sedation (PS). METHODS: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS. Patients were monitored for vital signs, depth of sedation per the physician by the Observer's Assessment of Alertness/Sedation scale (OAA/S), pulse oximetry, and nasal-sample ETCO2 during PS. Respiratory depression was defined as an oxygen saturation <90%, an ETCO2 >50 mm Hg, or an absent ETCO2 waveform at any time during the procedure. The physician also determined whether protective airway reflexes were lost during the procedure and assisted ventilation was required, or whether there were any other complications. Rates of RD were compared with the physician assessment of airway loss and between agents using chi-square statistics. Spearman's rho analysis was used to determine whether there was a correlation between ETCO2 and the OAA/S score. RESULTS: Seventy-four patients were enrolled in the study. Forty (54.1%) received methohexital, 21 (28.4%) received propofol, ten (13.5%) received fentanyl and midazolam, and three (4.1%) received etomidate. Respiratory depression was seen in 33 (44.6%) patients, including 47.5% of patients receiving methohexital, 19% receiving propofol (p = 0.008), 80% receiving fentanyl and midazolam, and 66.6% receiving etomidate. No correlation between OAA/S and ETCO2 was detected. Eleven (14.9%) patients required assisted ventilation at some point during the procedure, all of whom met the criteria for RD. Pulse oximetry detected 11 of the 33 patients with RD. Post-hoc analysis revealed that all patients with RD had an ETCO2 >50 mm Hg, an absent waveform, or an absolute change from baseline in ETCO2 >10 mm Hg. CONCLUSIONS: There was no correlation between ETCO2 and the OAA/S score. Using the criteria of an ETCO2 >50 mm Hg, an absolute change >10 mm Hg, or an absent waveform may detect subclinical RD not detected by pulse oximetry alone. The ETCO2 may add to the safety of PS by quickly detecting hypoventilation during PS in the ED.  相似文献   
58.
The impact of trauma is a major public health challenge which is likely to escalate in the early 21st century. A systematic approach to this problem is required. This review explains the conceptual framework that defines a trauma system, gives a brief historical perspective and describes some of the essential elements of the system which should make a difference to patient outcome. Emergency physicians are well placed to play a leading role in the development and implementation of trauma systems.  相似文献   
59.
The aim of this study was to determine if the effect of psychosocial work environment on psychological well‐being was different for doctors and nurses who work in emergency departments in Spain. A cross‐sectional survey was carried out among 945 emergency doctors and nurses staff from Spain. The outcome variable was the psychological well‐being measured by two dimensions of SF‐36 Health Survey (SF‐36) (mental health, vitality) and one dimension of Maslach's Burnout Inventory (emotional exhaustion). The explanatory variable was the psychosocial work environment evaluated according to Karasek and Johnson's demand‐control model that includes the dimensions of psychological demands, job control, supervisor social support and co‐workers' social support. The adjusted odds ratios and their 95 per cent confidence intervals were calculated by logistic regression. The prevalence of low vitality, bad mental health and high emotional exhaustion was higher among doctors than nurses. Exposure to high psychological demands increased the probability of low vitality, bad mental health and high emotional exhaustion among doctors and nurses. Low job control and low co‐workers' social support at work were associated with poor psychological well‐being only among doctors. Low job supervisors' social support increased the risk of bad mental health among doctors and of high emotional exhaustion among nurses. There is a different effect of psychosocial work environment on psychological well‐being between doctors and nurses. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
60.
There is a need for every medical school graduate to handle emergencies as they arise in the daily practice of medicine. Emergency medicine (EM) educators are in a unique position to provide students with basic life support skills, guidance in assessing the undifferentiated patient, and exposure to the specialty of EM during all years of medical school. Emergency physicians can become involved in a variety of education experiences that can supplement the preclinical curriculum and provide access to our specialty at an early stage. A well-designed course in the senior year allows students to develop critical thinking and patient management skills that are necessary for any medical career path. It can ensure that all medical students are exposed to the skills essential for evaluating and stabilizing the acutely ill patient. To implement this type of course, learning objectives and evaluation methods must be set when the curriculum is developed. An effective course combines didactic and clinical components that draw on the strengths of the teaching institution and faculty of the department. A structured clerkship orientation session and system for feedback to students are essential in nurturing the development of student learners. This article provides an approach to assist the medical student clerkship director in planning and implementing EM education experiences for students at all levels of training, with an emphasis on the senior-year rotation.  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