全文获取类型
收费全文 | 1767篇 |
免费 | 195篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 30篇 |
妇产科学 | 28篇 |
基础医学 | 301篇 |
口腔科学 | 28篇 |
临床医学 | 202篇 |
内科学 | 374篇 |
皮肤病学 | 35篇 |
神经病学 | 99篇 |
特种医学 | 21篇 |
外科学 | 251篇 |
综合类 | 51篇 |
一般理论 | 1篇 |
预防医学 | 259篇 |
眼科学 | 19篇 |
药学 | 119篇 |
中国医学 | 4篇 |
肿瘤学 | 133篇 |
出版年
2023年 | 21篇 |
2022年 | 16篇 |
2021年 | 73篇 |
2020年 | 46篇 |
2019年 | 52篇 |
2018年 | 73篇 |
2017年 | 50篇 |
2016年 | 48篇 |
2015年 | 56篇 |
2014年 | 76篇 |
2013年 | 84篇 |
2012年 | 130篇 |
2011年 | 139篇 |
2010年 | 61篇 |
2009年 | 55篇 |
2008年 | 95篇 |
2007年 | 114篇 |
2006年 | 93篇 |
2005年 | 78篇 |
2004年 | 78篇 |
2003年 | 50篇 |
2002年 | 56篇 |
2001年 | 29篇 |
2000年 | 37篇 |
1999年 | 30篇 |
1998年 | 27篇 |
1997年 | 21篇 |
1996年 | 18篇 |
1995年 | 14篇 |
1994年 | 19篇 |
1993年 | 9篇 |
1992年 | 25篇 |
1991年 | 18篇 |
1990年 | 12篇 |
1989年 | 17篇 |
1988年 | 22篇 |
1987年 | 22篇 |
1986年 | 12篇 |
1985年 | 14篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1974年 | 9篇 |
1972年 | 6篇 |
1961年 | 3篇 |
1955年 | 3篇 |
排序方式: 共有1971条查询结果,搜索用时 265 毫秒
1.
2.
Will Kaufman Augustine S Chavez Betty Skipper Arthur Kaufman 《International journal for equity in health》2006,5(1):6-5
Background
A public hospital in New Mexico required collection of 50% of estimated costs prior to elective surgeries for self-pay patients. This study assesses the impact of this policy on access to elective surgical procedures. 相似文献3.
David C. Cone MD Susan M. Nedza MD MBA James J. Augustine MD Steven J. Davidson MD MBA 《Academic emergency medicine》2002,9(11):1085-1090
This paper reports the proceedings of the discussion panel assigned to look at clinical aspects of quality in emergency medicine. One of the seven stated objectives of the Academic Emergency Medicine consensus conference on quality in emergency medicine was to educate emergency physicians regarding quality measures and quality improvement as essential aspects of the practice of emergency medicine. Another topic of interest was a discussion of the value of information technology in facilitating quality care in the clinical practice of emergency medicine. It is important to note that this is not intended to be a comprehensive review of this extensive topic, but instead is designed to report the discussion that occurred at this session of the consensus conference. 相似文献
4.
5.
D Anderson S Goyle B J Phillips A Tee L Beech W H Butler 《Occupational and environmental medicine》1988,45(4):269-274
Since the Bhopal disaster, in which the causal agent was methyl isocyanate (MIC), exposed people have complained of various disorders including neuromuscular dysfunction. In an attempt to gain some information about the response of muscle tissue to MIC its effects were investigated in cells in culture isolated from muscle of 2 day old rats. After treatment with a range of MIC concentrations (0.025-0.5 microliter/5 ml culture) the total number of nuclei of the two main cell types (fibroblasts and myoblasts) and the number of nuclei in muscle fibres (myotubes) were recorded. At lower doses which had little effect on the total number of nuclei, the formation of muscle fibres--that is, fusion of muscle cells--was prevented as the proportion of nuclei in myotubes was decreased. At higher doses both cell types were killed. This would suggest either an effect on muscle differentiation or a selective toxicity towards myoblasts. The observations were supported by light and electron microscopy. 相似文献
6.
K Prakash H Ramesh G Jacob A Venugopal V Lekha D Varma G N Ramesh P Augustine 《Indian journal of gastroenterology》2004,23(6):209-213
BACKGROUND: Intrahepatic stones, though common in East Asia, are uncommon in India. There is paucity of data from India regarding the treatment and long-term outcome of patients with intrahepatic stones. METHODS: We retrospectively analyzed medical records of 35 patients with intrahepatic stones who had been treated surgically. Endoscopic biliary drainage had been used in patients who presented with acute cholangitis. Intraoperative stone clearance was confirmed by choledochoscopy and intraoperative cholangiography. Outcome of surgery, frequency and subsequent management of recurrent intrahepatic stones, and factors associated with stone recurrence and cholangitis were analyzed. RESULTS: Twenty-one (60%) patients had bilobar disease. Eight patients underwent hepatectomy and 16 hepatico-jejunostomy with access loop; 12 of these were jejuno-duodenal anastomoses. Postoperative morbidity was observed in 10 patients (29%). Recurrence of stones occurred in 12 patients (34%) and cholangitis in 9 patients (26%). Presence of bilobar disease and associated biliary strictures were associated with recurrent cholangitis (p< 0.05). Two patients (6%) required re-operation for recurrent cholangitis. Complete removal of recurrent stones using conventional endoscope was possible through jejuno-duodenostomy in all 5 cases who had this type of access loop construction. CONCLUSION: Surgical treatment for intrahepatic stones depends on the site of involvement. Construction of a jejuno-duodenal access loop in patients with bilobar disease and intrahepatic strictures is helpful in facilitating postoperative stone clearance. A multidisciplinary approach is beneficial especially when the disease is bilobar and recurrent in type. 相似文献
7.
8.
Summary There are many issues in firefighting that involve human factors and cardiopulmonary conditioning. Population-based mortality and disability surveillance studies suggest a relatively small but significant excess of disability but not mortality from nonmalignant cardiovascular disease for fire fighters. More targeted cohort and case-control studies do not support such an excess and instead suggest a strong healthy worker effect. Pulmonary function among fire fighters has been extensively studied, with contradictory findings. Extreme exposures and long-term exposure in combination with cigarette smoking may be risk factors for respiratory disorders and accelerated decline in airflow. It appears likely that individual fire fighters who show early signs of illness are often selectively transferred out of active firefighting positions. Despite exposure to substances such as carbon monoxide that may predispose to cardiovascular mortality and morbidity, excesses are not consistently shown in mortality studies. Clinical studies of individual fire fighters do suggest an elevated risk for myocardial ischemia. The ergonomic demands of firefighting are extreme at peak activity because of high energy costs for activities such as climbing aerial ladders, the positive heat balance from endogenous and absorbed environmental heat, and encumbrance by bulky but necessary protective equipment. The psychological stresses of firefighting include long periods of relative inactivity punctuated by highly stressful alarms and extremely stressful situations such as rescues, as reflected in physiological and biochemical indicators. Fire fighters are at risk for depression and posttraumatic stress disorder, although morale overall is generally much higher than in comparable occupations. Women firefighter candidates as a group perform less well on selection test simulating the demands of active firefighting, but some individual women perform very well. 相似文献
9.
The toxicity of paracetamol has been investigated in freshly isolated hamster hepatocytes. Two phases of toxicity have been identified. In phase 1, metabolic activation of paracetamol occurs with depletion of glutathione. In phase 2, there is progressive morphological damage, leading ultimately to cell death. This occurs even in the absence of further exposure to paracetamol. The thiol reductant, dithiothreitol, added at the start of phase 2, prevents and reverses the toxicological damage that would otherwise occur. Thus, it is most likely that paracetamol causes hepatotoxicity through oxidation of SH groups in key enzymes. N-Acetylcysteine, but not methionine, has an effect similar to that of dithiothreitol. This difference is probably due to oxidation of the enzymes involved in the conversion of methionine to cysteine, whereas N-acetylcysteine can still serve as a precursor of glutathione. The glutathione can act both by adduct formation with the metabolite of paracetamol and as a thiol reductant. Species differences in sensitivity to paracetamol toxicity were shown to be due to differences in the rate of oxidation of the drug to its toxic metabolite. Most people are relatively poor activators of paracetamol, but in few subjects the reaction proceeds quite rapidly, rendering such individuals more sensitive to the hepatotoxic effects of the drug. 相似文献
10.
Adequate ventilation is required for successful cardiopulmonary resuscitation (CPR). Operator characteristics that influence ventilation performance are not well defined. This study compared ventilation performance and operator characteristics in 74 medical personnel using a self-inflating anesthesia bag. Ventilation device, operator hand size, ventilation technique, average tidal volume, cumulative minute ventilation, and ventilation pressures were recorded during 3 minutes of ventilation. Ventilation volumes and airway pressures were not correlated with hand size or device type. Techniques that used one hand to squeeze the bag resulted in significantly lower average tidal volume than two-handed techniques, with no significant difference in peak or average airway pressure. There was no difference between emergency department and prehospital personnel in average tidal volume delivered. However, prehospital personnel ventilated at significantly higher airway pressures. Emergency department nurses delivered the greatest average tidal volume (923 cc), while emergency department physicians delivered the least (775 cc). Paramedics recorded the highest airway pressures (average, 53 cm H2O; peak, 72 cm H2O), while respiratory therapists recorded the lowest pressures (average, 34 cm H2O; peak, 54 cm H2O). Ventilation during CPR is a complex, learned skill. Large variation exists among different operators. However, appropriate tidal volumes can be delivered using safe airway pressures. Ongoing assessment and retraining of individuals performing ventilation during CPR are essential. 相似文献