全文获取类型
收费全文 | 24037篇 |
免费 | 2087篇 |
国内免费 | 662篇 |
专业分类
耳鼻咽喉 | 752篇 |
儿科学 | 1852篇 |
妇产科学 | 65篇 |
基础医学 | 5778篇 |
口腔科学 | 31篇 |
临床医学 | 1653篇 |
内科学 | 5120篇 |
皮肤病学 | 357篇 |
神经病学 | 90篇 |
特种医学 | 288篇 |
外科学 | 343篇 |
综合类 | 3936篇 |
现状与发展 | 3篇 |
预防医学 | 1595篇 |
眼科学 | 51篇 |
药学 | 2844篇 |
27篇 | |
中国医学 | 1819篇 |
肿瘤学 | 182篇 |
出版年
2024年 | 54篇 |
2023年 | 262篇 |
2022年 | 508篇 |
2021年 | 894篇 |
2020年 | 857篇 |
2019年 | 793篇 |
2018年 | 751篇 |
2017年 | 867篇 |
2016年 | 971篇 |
2015年 | 923篇 |
2014年 | 1545篇 |
2013年 | 2699篇 |
2012年 | 1451篇 |
2011年 | 1546篇 |
2010年 | 1166篇 |
2009年 | 1086篇 |
2008年 | 1074篇 |
2007年 | 1238篇 |
2006年 | 1122篇 |
2005年 | 919篇 |
2004年 | 775篇 |
2003年 | 669篇 |
2002年 | 611篇 |
2001年 | 546篇 |
2000年 | 430篇 |
1999年 | 430篇 |
1998年 | 341篇 |
1997年 | 335篇 |
1996年 | 269篇 |
1995年 | 159篇 |
1994年 | 177篇 |
1993年 | 131篇 |
1992年 | 115篇 |
1991年 | 107篇 |
1990年 | 112篇 |
1989年 | 71篇 |
1988年 | 107篇 |
1987年 | 105篇 |
1986年 | 105篇 |
1985年 | 99篇 |
1984年 | 63篇 |
1983年 | 47篇 |
1982年 | 51篇 |
1981年 | 43篇 |
1980年 | 48篇 |
1979年 | 29篇 |
1978年 | 23篇 |
1977年 | 20篇 |
1976年 | 14篇 |
1972年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
娄耀君 《华北煤炭医学院学报》2002,4(3):284-285
(1)目的 探讨鼻内窥镜下Nd:YAG激光治疗变应性鼻炎的方法。(2)方法 应用鼻内镜下Nd:YAG激光凝固中务甲前1/3端治疗变应性鼻炎126例。(3) 结果 随访1年,显效109例(86.5%),有效13例(10.3%),无效4例(3.2%),总有效率96.8%。(4)结论 鼻内镜下Nd:YAG激光凝固中鼻甲前1.3端治疗变应性鼻炎,具有视野清楚,操作简便,疗效好等优点,值得临床应用。 相似文献
82.
BACKGROUND: Feather bedding has long been considered as a potential source of allergen exposure and thus a potential risk factor for allergic diseases. However, recent cross-sectional studies have reported a higher risk of allergic diseases among users of synthetic bedding compared with feather-bedding users. OBJECTIVE: To explore associations between early life exposure to feather bedding and the risk of developing asthma allergic rhinitis in childhood. METHODS: We assessed the association between early life exposure to feather quilts and the risk of bronchial obstruction during the first 2 years of life and asthma and allergic rhinitis in a prospective 4-year cohort study of 2531 Norwegian children. RESULTS: At the age of 6 months, 24% of the children had a quilt with feathers, decreasing to 20% at the age of 2 years. The adjusted odds ratio for bronchial obstruction 0 to 2 years by exposure to a feather quilt at the age of 6 months was 0.59, 95% confidence interval 0.41 to 0.86, for asthma at the age of 4 years 0.38, 0.23 to 0.64 and for allergic rhinitis at the age of 4 years 0.73, 0.43 to 1.18. CONCLUSION: The use of a feather quilt in early life does not seem to increase the risk of asthma and allergic rhinitis later in childhood. 相似文献
83.
R. Nickel S. Lau B. Niggemann C. Sommerfeld U. Wahn the German Multicenter Allergy Study Group 《Clinical and experimental allergy》2002,32(9):1274-1277
BACKGROUND: Bronchial responsiveness (BR) to histamine or methacholin is a common finding in adult non-asthmatic patients with allergic rhinitis. OBJECTIVE: We tested whether BR is also present in children with a comparatively short history of allergic rhinitis in a paediatric cohort. METHODS: We performed pulmonary function tests and histamine challenges in a total of 654 children (age 7 years, participants of the German Multicenter Allergy Study) and compared PC20 FEV1 values in children with asthma, allergic rhinitis, asymptomatic allergic sensitization and non-atopic controls. RESULTS: Most pronounced BR to histamine was observed in allergic asthmatics (n = 28), irrespective of the presence or absence of allergic rhinitis. Furthermore, PC(20)FEV(1) values in non-asthmatic children with allergic rhinitis (n = 24) were not significantly different from those seen in asymptomatic atopic (n = 54) or non-atopic controls (n = 92). CONCLUSIONS: In contrast to adult study populations, 7-year-old non-asthmatic children with allergic rhinitis do not show a higher degree of BR than asymptomatic atopic or non-atopic controls. Therefore, secondary preventive measures in non-asthmatic children with allergic rhinitis (such as regular local anti-inflammatory therapy or specific immunotherapy) should be studied and applied more intensely to prevent bronchial hyper-responsiveness (BHR) and asthma in this high-risk group. 相似文献
84.
Jasminka Godnic-Cvar 《International archives of occupational and environmental health》1995,67(2):79-84
A methodological overview is provided on the important question of how to confirm occupational asthma in routine work. Recent knowledge gained in immunology and occupational allergy has been utilized, supplemented by an overview of recent publications on the diagnosis and pathophysiology of occupational asthma. The aim of the paper is to facilitate decision making for an investigator dealing with individual cases of occupational asthma. Moreover, by presenting stepping-stones in the diagnostic cascade, the author hopes to encourage the less experienced to conduct a comprehensive and cause-oriented diagnostic procedure. Methods which are being worked on at present (standardization) are discussed in more detail. Finally, the research goals in the understanding, confirmation, and prevention of occupational asthma are listed. 相似文献
85.
Accidental bronchial intubation An analysis of AIMS incident reports from 1988 to 1994 inclusive 总被引:2,自引:0,他引:2
Accidental bronchial intubation was examined in the first 3947 cases reported to the Australian Incident Monitoring Study and was found to have accounted for 154 (3.7%) of the total incidents reported. Most incidents were detected in the operating theatre (93.5%) and during maintenance of anaesthesia (77.9%), by unexplained oxygen desaturation alone (63.6%). Capnography remained normal or unremarkable during 88.5% of the episodes. One-third of cases were associated with head or neck surgery and possible flexion of the patient's head. A RAE tube was used in 20% of incidents, a greater frequency than occurred in the study overall. A third party was implicated in 36 (23.4%) of cases. Ninety per cent of cases were considered preventable. Major morbidity occurred in three cases and unplanned intensive care admission was required in a further five. Almost two-thirds (61.1%) of the incidents might have been avoided by the proposed markings on the tracheal tube. We conclude that when arterial desaturation occurs at any stage during anaesthesia the possibility of bronchial intubation must be considered. Asymmetrical ventilation may be difficult to detect clinically and in most cases there is no change in capnography. 相似文献
86.
W. A. Shaikh 《Allergy》1992,47(4):327-330
Inhaled beclomethasone dipropionate (BDP) has been used with few side effects in the treatment of bronchial asthma for 2 decades. Until now the manifestation of tuberculosis (TB) in patients on inhaled BDP has not been reported. Eight patients with allergic asthma, of a total of 548 asthmatics (1.46%) seen over a 2-year period, developed active TB following the use of inhaled BDP. All were sputum-positive for acid-fast bacilli (AFB) on smear and/or culture, all responded well to a combination of anti-TB drugs, and none showed evidence of immunological or pituitary-adrenal suppression. Two patients agreed to a repeat administration of BDP; both developed TB again within 2 weeks and are again on anti-TB treatment. 相似文献
87.
色甘酸钠混悬气雾剂与茶碱缓释胶囊治疗中度哮喘的比较 总被引:1,自引:1,他引:0
84例中度哮喘病人分成2组。色甘酸钠组(男性23例,女性20例,年龄26±s8a)吸入色甘酸钠混悬气雾剂10.5mg,tid。茶碱缓释胶囊组(男性22例,女性19例,年龄27±8a)口服0.25g。bid。2组均连续观察3mo。结果:色甘酸钠在减轻病人慢性症状、改善肺功能和降低气道高反应性等方面优于茶碱缓释胶囊,(P<0.01)。而后药仅可缓解近期症状。 相似文献
88.
H. W. Chu S. Balzar J. Y. Westcott J. B. Trudeau Y. Sun D. J. Conrad S. E. Wenzel 《Clinical and experimental allergy》2002,32(11):1558-1565
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels. 相似文献
89.
Lower airway inflammatory responses to repeated very-low-dose allergen challenge in allergic rhinitis and asthma 总被引:2,自引:0,他引:2
BACKGROUND: Low-dose allergen challenge (LDAC) may be a useful tool for studying the capacity of allergens to induce airway inflammation in atopic subjects. OBJECTIVE: To evaluate lower airway inflammatory changes following repeated inhalation of very low doses of allergen (VLDAC) in non-asthmatic subjects with allergic rhinitis (NAAR) compared with mild allergic asthmatic subjects (AA). METHODS: Fourteen NAAR and 11 AA were seen out of the pollen season and had skin prick tests with common aeroallergens. Baseline spirometry (S) and methacholine challenge (MC) were done and blood and induced sputum (IS) differential cell counts were obtained. Each subject underwent VLDAC on four consecutive mornings with a relevant allergen. S, MC, and blood and IS samplings were repeated 6 h after the second and fourth VLDAC and one week later. RESULTS: Although there were, as expected, no changes in FEV1 or PC20 in either group, mean percentage eosinophils on IS were significantly increased in NAAR on day 2 of VLDAC and decreased in all but one subject on day 4, with a tendency to return to baseline levels one week later. In AA, there was a non-significant trend for sputum eosinophils to increase on day 2; four subjects showed a decrease of eosinophils on day 4 of VLDAC. There was a correlation between eosinophil cationic protein (ECP) levels and eosinophil counts in NAAR throughout the study. There were no variations in other sputum cells or blood inflammatory cells. CONCLUSION: VLDAC can increase the percentage of eosinophils in IS of NAAR subjects without associated respiratory symptoms nor physiological modifications. A reduction in eosinophilic response despite repeated exposure, more common in NAAR subjects, suggests an adaptation process that needs to be further evaluated. 相似文献
90.