全文获取类型
收费全文 | 3532140篇 |
免费 | 272913篇 |
国内免费 | 7070篇 |
专业分类
耳鼻咽喉 | 50037篇 |
儿科学 | 112338篇 |
妇产科学 | 94888篇 |
基础医学 | 498735篇 |
口腔科学 | 103442篇 |
临床医学 | 321996篇 |
内科学 | 684166篇 |
皮肤病学 | 75486篇 |
神经病学 | 287639篇 |
特种医学 | 137442篇 |
外国民族医学 | 1084篇 |
外科学 | 533310篇 |
综合类 | 84026篇 |
现状与发展 | 5篇 |
一般理论 | 1398篇 |
预防医学 | 278819篇 |
眼科学 | 84547篇 |
药学 | 264132篇 |
11篇 | |
中国医学 | 7744篇 |
肿瘤学 | 190878篇 |
出版年
2018年 | 38176篇 |
2017年 | 29163篇 |
2016年 | 32454篇 |
2015年 | 36908篇 |
2014年 | 52182篇 |
2013年 | 78114篇 |
2012年 | 106528篇 |
2011年 | 112434篇 |
2010年 | 66560篇 |
2009年 | 62748篇 |
2008年 | 105321篇 |
2007年 | 112021篇 |
2006年 | 112885篇 |
2005年 | 109458篇 |
2004年 | 105351篇 |
2003年 | 100996篇 |
2002年 | 98698篇 |
2001年 | 166892篇 |
2000年 | 172119篇 |
1999年 | 144908篇 |
1998年 | 41240篇 |
1997年 | 36767篇 |
1996年 | 36422篇 |
1995年 | 35229篇 |
1994年 | 32877篇 |
1993年 | 30464篇 |
1992年 | 114866篇 |
1991年 | 111208篇 |
1990年 | 107305篇 |
1989年 | 103646篇 |
1988年 | 95711篇 |
1987年 | 94006篇 |
1986年 | 88866篇 |
1985年 | 84774篇 |
1984年 | 63822篇 |
1983年 | 54395篇 |
1982年 | 32232篇 |
1981年 | 28783篇 |
1979年 | 58810篇 |
1978年 | 41074篇 |
1977年 | 34896篇 |
1976年 | 32658篇 |
1975年 | 34474篇 |
1974年 | 42428篇 |
1973年 | 40478篇 |
1972年 | 37897篇 |
1971年 | 34993篇 |
1970年 | 32876篇 |
1969年 | 30592篇 |
1968年 | 28092篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
灾难的时代错误:灾害医学的过去、现在和将来(一) 总被引:1,自引:0,他引:1
灾难,特别是地震、火山、洪水以及与战争有关的事件如饥饿和流行性传染病,是人类有记录的经历的一部分。从意大利庞贝的火山爆发,到约翰斯顿的洪水、第二次世界大战和黑色瘟疫,到西班牙流感,都发生了灾难,这不会被传说和历史书籍长期忘却。不过,在20世纪中叶以前,那些灾难的发生相对较少,且相距时间较长。从20世纪中叶以来,灾难的本质发生了变化。从恐怖分子使用“新技术”,到与气候有关的导致亿万美元经济损失的事件,表明这个世界正在发生变化。仅仅在最近的50~60年间,造成多种多样的伤亡事件,其危险性和频率的增加引人注目,并且注定要在接… 相似文献
992.
993.
R E Dales A Mehdizadeh S D Aaron K L Vandemheen J Clinch 《The European respiratory journal》2006,28(2):319-322
The aim of the present study was to explore differences in the clinical expression, clinical diagnoses and management of airway diseases in a primary-care setting. Patients aged >or=35 yrs who had ever smoked were enrolled when they presented for any reason to one of eight rural primary-care practices. Respiratory symptom questionnaires and spirometry were administered. In total, 1,034 patients had acceptable and reproducible spirometry, of whom 550 (53%) were males and 484 (47%) were females. Males smoked more than females (41.2 versus 29.2 pack-yrs) respectively, and were more likely to have a pre-bronchodilator forced expiratory volume in one second/forced vital capacity <0.70 at 22.4 versus 11.8%, respectively. However, more females than males reported breathlessness (51.0 versus 42.8%, respectively), a prior diagnosis compatible with airflow obstruction and taking respiratory medications (23.4 versus 14.9%, respectively). In conclusion, the current results suggest that females are more likely than males to report breathlessness and be prescribed respiratory medications independent of differences in the severity of airflow obstruction. 相似文献
994.
Body weight and comorbidity predict mortality in COPD patients treated with oxygen therapy. 总被引:1,自引:0,他引:1
The aim of this study was to investigate the association between clinical variables and all-cause and respiratory mortality in patients with chronic obstructive pulmonary disease (COPD) undergoing long-term oxygen therapy (LTOT). The authors retrospectively studied a historic cohort of 128 patients with COPD (126 males, mean age+/-SD 68.9+/-9.7 yrs, body mass index (BMI) 25.1+/-4.5 kg.m-2, and forced expiratory volume in one second 25.4+/-8.8% predicted), who were being treated with long-term oxygen therapy in a tertiary teaching hospital between 1992 and 1999. Comorbidity, assessed with the Charlson Index, was present in 38% of the patients. Vital status and cause of death were assessed through the population death registry. A total of 78 patients (61%) had died by the end of follow-up. Three-year survival was 55%. Death was due to respiratory causes in 77% of cases. On Cox analysis, BMI<25 kg.m-2, comorbid conditions, age>or=70 yrs and cor pulmonale were associated with all-cause mortality. The BMI and comorbidity were the only significant predictive factors when the analysis was restricted to respiratory mortality. In conclusion, body mass index<25 kg.m-2 and comorbidity were predictors of all-cause and respiratory mortality in a cohort of chronic obstructive pulmonary disease patients treated with long-term oxygen therapy. These factors should be taken into account when considering the management and prognosis of these patients. 相似文献
995.
M Bernasconi P N Chhajed F Gambazzi L Bubendorf H Rasch S Kneifel M Tamm 《The European respiratory journal》2006,27(5):889-894
There are no data available combining transbronchial needle aspiration (TBNA) of mediastinal lymph nodes and positron emission tomography (PET) in the staging of nonsmall cell lung cancer (NSCLC). The aim of the current study was to determine if these two methods can enhance the negative predictive value of the individual modality alone, for a specific lymph node station, and if this integrated approach can reduce the number of mediastinoscopies. A total of 113 patients with enlarged mediastinal lymph nodes (> or = 1 cm), who underwent both TBNA and PET scanning, were included. In 51 patients, histopathology, confirmed by surgical lymph node dissection, was compared with PET results and TBNA. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy to detect malignant lymphadenopathy was 68 (13/19), 89 (119/134), 46 (13/28), 95 (119/125) and 86% (132/152) for PET, respectively; 54% (6/11), 100 (53/53), 100 (6/6), 91 (53/58) and 92% (59/64), respectively for TBNA; and 100 (11/11), 94 (50/53), 79 (11/14), 100 (50/50) and 95 (61/64) for combined TBNA and PET, respectively. Combination of transbronchial needle aspiration and positron emission tomography has the potential to allow adequate mediastinal staging of nonsmall cell lung cancer with enlarged lymph nodes in most patients without the need for mediastinoscopy. 相似文献
996.
997.
998.
J.L. Bernat A.M. D'Alessandro F.K. Port T.P. Bleck S.O. Heard J. Medina S.H. Rosenbaum M.A. DeVita R.S. Gaston R.M. Merion M.L. Barr W.H. Marks H. Nathan K. O'Connor D.L. Rudow A.B. Leichtman P. Schwab N.L. Ascher R.A. Metzger V. Mc Bride W. Graham D. Wagner J. Warren F.L. Delmonico 《American journal of transplantation》2006,6(2):281-291
A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States. 相似文献
999.
1000.
We report a case of cervical necrotizing fasciitis (CNF) in a female having uncontrolled type II diabetes mellitus. The patient was presented to us after 20 days of preliminary symptoms. The aetiology of microbial inoculation in subdermal tissue was not known. The isolate was Staphylococcus aureus. In spite of the delay in presentation, the patient was successfully treated with combined antimicrobial and surgical intervention. 相似文献