全文获取类型
收费全文 | 2796624篇 |
免费 | 199901篇 |
国内免费 | 7347篇 |
专业分类
耳鼻咽喉 | 36900篇 |
儿科学 | 92040篇 |
妇产科学 | 75788篇 |
基础医学 | 402299篇 |
口腔科学 | 80270篇 |
临床医学 | 259956篇 |
内科学 | 538019篇 |
皮肤病学 | 61180篇 |
神经病学 | 225639篇 |
特种医学 | 104094篇 |
外国民族医学 | 592篇 |
外科学 | 409378篇 |
综合类 | 62026篇 |
现状与发展 | 5篇 |
一般理论 | 975篇 |
预防医学 | 219492篇 |
眼科学 | 64946篇 |
药学 | 205115篇 |
12篇 | |
中国医学 | 6891篇 |
肿瘤学 | 158255篇 |
出版年
2021年 | 21918篇 |
2019年 | 23036篇 |
2018年 | 33731篇 |
2017年 | 25734篇 |
2016年 | 28598篇 |
2015年 | 31882篇 |
2014年 | 43656篇 |
2013年 | 66128篇 |
2012年 | 91008篇 |
2011年 | 96564篇 |
2010年 | 56780篇 |
2009年 | 51854篇 |
2008年 | 89656篇 |
2007年 | 95153篇 |
2006年 | 95480篇 |
2005年 | 91823篇 |
2004年 | 87916篇 |
2003年 | 83924篇 |
2002年 | 81384篇 |
2001年 | 134112篇 |
2000年 | 138182篇 |
1999年 | 114267篇 |
1998年 | 31691篇 |
1997年 | 27883篇 |
1996年 | 27658篇 |
1995年 | 26375篇 |
1994年 | 24452篇 |
1993年 | 22717篇 |
1992年 | 87278篇 |
1991年 | 84629篇 |
1990年 | 81532篇 |
1989年 | 78113篇 |
1988年 | 71673篇 |
1987年 | 70090篇 |
1986年 | 66382篇 |
1985年 | 63342篇 |
1984年 | 47185篇 |
1983年 | 40184篇 |
1982年 | 23471篇 |
1979年 | 42161篇 |
1978年 | 29649篇 |
1977年 | 24895篇 |
1976年 | 23639篇 |
1975年 | 24612篇 |
1974年 | 29878篇 |
1973年 | 28943篇 |
1972年 | 26829篇 |
1971年 | 24927篇 |
1970年 | 23179篇 |
1969年 | 21467篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
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
103.
L Bernardi A Schneider L Pomidori E Paolucci A Cogo 《The European respiratory journal》2006,27(1):165-171
A very high ventilatory response to hypoxia is believed necessary to reach extreme altitude without oxygen. Alternatively, the excessive ventilation could be counterproductive by exhausting the ventilatory reserve early on. To test these alternatives, 11 elite climbers (2004 Everest-K2 Italian Expedition) were evaluated as follows: 1) at sea level, and 2) at 5,200 m, after 15 days of acclimatisation at altitude. Resting oxygen saturation, minute ventilation, breathing rate, hypoxic ventilatory response, maximal voluntary ventilation, ventilatory reserve (at oxygen saturation = 70%) and two indices of ventilatory efficiency were measured. Everest and K2 summits were reached 29 and 61 days, respectively, after the last measurement. Five climbers summited without oxygen, the other six did not, or succeeded with oxygen (two climbers). At sea level, all data were similar. At 5,200 m, the five summiters without oxygen showed lower resting minute ventilation, breathing rate and ventilatory response to hypoxia, and higher ventilatory reserve and ventilatory efficiency, compared to the other climbers. Thus, the more successful climbers had smaller responses to hypoxia during acclimatisation to 5,200 m, but, as a result, had greater available reserve for the summit. A less sensitive hypoxic response and a greater ventilatory efficiency might increase ventilatory reserve and allow sustainable ventilation in the extreme hypoxia at the summit. 相似文献
104.
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
105.
106.
107.
108.
Shabnam Golmarvi Katleen Devue S Hachimi-Idrissi 《European journal of emergency medicine》2006,13(5):299-301
Group A streptococcal meningitis is less common than other forms of meningitis; however, the occurrence of this infection is associated with high mortality and morbidity. Early recognition and a prompt treatment are therefore essential. We review one case of an Asian women admitted with group A streptococcal meningitis as a complication of otitis media. 相似文献
109.
110.
Ajay Punpale C S Pramesh Nirmala Jambhekar Rajesh C Mistry 《Annals of thoracic and cardiovascular surgery》2006,12(6):425-427
Liposarcomas are extremely rare in the mediastinum. They may achieve considerable size before causing any symptoms. Mediastinal liposarcomas may invade surrounding structures like the pericardium or the superior vena cava. Complete surgical excision is the optimal treatment in resectable cases. Excision of adjacent structures like the pericardium may be needed if the tumor infiltrates them. We report on a case of a giant liposarcoma of the mediastinum involving both hemithoraces and extending into the neck, which was successfully managed by complete surgical excision. 相似文献