全文获取类型
收费全文 | 138376篇 |
免费 | 6019篇 |
国内免费 | 321篇 |
专业分类
耳鼻咽喉 | 2251篇 |
儿科学 | 4301篇 |
妇产科学 | 3040篇 |
基础医学 | 18667篇 |
口腔科学 | 4732篇 |
临床医学 | 8540篇 |
内科学 | 34290篇 |
皮肤病学 | 4539篇 |
神经病学 | 10820篇 |
特种医学 | 3091篇 |
外国民族医学 | 1篇 |
外科学 | 17124篇 |
综合类 | 768篇 |
一般理论 | 38篇 |
预防医学 | 13500篇 |
眼科学 | 3095篇 |
药学 | 9312篇 |
中国医学 | 699篇 |
肿瘤学 | 5908篇 |
出版年
2023年 | 880篇 |
2022年 | 803篇 |
2021年 | 3031篇 |
2020年 | 1574篇 |
2019年 | 3312篇 |
2018年 | 5347篇 |
2017年 | 3098篇 |
2016年 | 2894篇 |
2015年 | 3234篇 |
2014年 | 3828篇 |
2013年 | 5680篇 |
2012年 | 9828篇 |
2011年 | 10491篇 |
2010年 | 5375篇 |
2009年 | 3880篇 |
2008年 | 8382篇 |
2007年 | 8895篇 |
2006年 | 8332篇 |
2005年 | 8179篇 |
2004年 | 7200篇 |
2003年 | 6779篇 |
2002年 | 6400篇 |
2001年 | 4125篇 |
2000年 | 4790篇 |
1999年 | 3583篇 |
1998年 | 606篇 |
1997年 | 395篇 |
1996年 | 366篇 |
1995年 | 316篇 |
1994年 | 238篇 |
1992年 | 1379篇 |
1991年 | 1143篇 |
1990年 | 1032篇 |
1989年 | 843篇 |
1988年 | 713篇 |
1987年 | 678篇 |
1986年 | 685篇 |
1985年 | 602篇 |
1984年 | 426篇 |
1983年 | 329篇 |
1979年 | 347篇 |
1975年 | 280篇 |
1974年 | 340篇 |
1973年 | 368篇 |
1972年 | 312篇 |
1971年 | 329篇 |
1970年 | 323篇 |
1969年 | 324篇 |
1968年 | 287篇 |
1967年 | 256篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Prevalence of Artemisia species pollinosis in western Poland: impact of climate change on aerobiological trends, 1995-2004. 总被引:2,自引:0,他引:2
A Stach H García-Mozo J C Prieto-Baena M Czarnecka-Operacz D Jenerowicz W Silny C Galán 《Journal of investigational allergology & clinical immunology》2007,17(1):39-47
BACKGROUND: Artemisia species pollen represents a major cause of allergy in Central Europe. Variations in the pollen season, the influence of climate variables and the prevalence of pollinosis to it were analyzed in Poznan, in western Poland between 1995 and 2004. METHODS: A Hirst volumetric spore trap was used for atmospheric sampling. Pollination date trend analysis and Spearman correlation tests were performed. Skin prick tests (SPT) and allergen specific immunoglobulin (lg)E antibody measurements were performed in 676 and 524 patients, respectively. RESULTS: The Artemisia species pollen season grew longer due to a clear advance in the starting day and only a slightly earlier end point; the peak day also came slightly earlier. Rainfall in the first fortnight of July highly influenced pollen season severity. Temperature was directly correlated with daily Artemisia species pollen levels; relative humidity was inversely correlated. Twelve percent of patients had a positive SPT reaction to Artemisia species. Their symptoms were rhinitis and conjunctivitis (15%), atopic dermatitis (15%), chronic urticaria (14.3%), bronchial asthma (2.4%), and facial and disseminated dermatitis (1.3%). Elevated specific IgE concentrations were detected in the sera of 10.1% of patients. CONCLUSIONS: Artemisia species pollen is an important cause of pollinosis in western Poland. Pollen season intensity is highly influenced by rainfall in the previous weeks. Trends towards earlier season starts and longer duration, possibly caused by climate change, may have an impact on the allergic population. 相似文献
42.
43.
C Martín-García J Carnés R Blanco J C Martínez-Alonso A Callejo-Melgosa A Frades T Colino 《Journal of investigational allergology & clinical immunology》2007,17(4):271-273
Many types of seafood require cooking before ingestion and it has been demonstrated that this cooking process may affect the antigenicity and allergenicity of the food. We describe a case of anaphylaxis caused by selective sensitization to razor shell, a mollusc. In vivo and in vitro studies confirmed sensitization to boiled razor shell. Analysis of the nature of the allergen yielded results that were consistent with the findings of other authors and suggested that allergens involved in seafood allergy are commonly high molecular weight proteins that, in most cases, are heat stable. 相似文献
44.
45.
46.
47.
48.
49.
Estrella Fernández Fabrellas Luis Almenar Bonet Silvia Ponce Pérez José Antonio Moro López Rafael Blanquer Olivas Antonio Salvador Sanz 《Archivos de bronconeumologia》2009,45(4):173-180
Introduction and objectiveWhen sleep apnea-hypopnea syndrome (SAHS) and cardiovascular disease occur concurrently, prognosis is affected. Echocardiography can detect structural cardiac abnormalities but using this technique in all patients would place a heavy burden on resources. The objective of this study was to investigate whether the N-terminal fraction of brain natriuretic peptide (NT-proBNP) can be used as a marker for silent heart disease.Patients and methodsNT-proBNP concentration was measured in the 114 consecutive patients with SAHS who underwent echocardiography before starting treatment. Left and right ventricular systolic and diastolic function, as well as structural abnormalities, were studied. Correlations between NT-proBNP concentration and the abnormalities detected were investigated. A receiver operating characteristics (ROC) curve was plotted for NT-proBNP concentration and cardiac abnormalities.ResultsData for 98 patients were finally analyzed. NT-proBNP concentration was significantly correlated with ventricular septal thickness (r=0.63), posterior wall thickness (r=0.45), and left ventricular enddiastolic diameter (r=0.51) (P<.0001 for all correlations). The area under the ROC curve was significant (0.870; 95% confidence interval, 0.801-0.939; P<.0001). Assuming that specificity would be more useful for clinical practice, we calculated that NT-proBNP concentrations below 100 and 200 pg/mL could rule out structural abnormalities with a reliability of 90% and 100%, respectively.ConclusionsNT-proBNP concentration was strongly correlated with echocardiographic abnormalities and so could be a useful tool for identifying patients who should be referred to the cardiologist. 相似文献
50.
Enrique Cases Luis Seijo Carlos Disdier María José Lorenzo Rosa Cordovilla Francisca Sanchis Marimar Lacunza Gregoria Sevillano Fátima Benito-Sendín 《Archivos de bronconeumologia》2009,45(12):591-596
IntroductionTo analyse the effectiveness and safety of the indwelling pleural catheter in the management of recurrent malignant pleural effusion.Patients and methodsA prospective multicentre study was performed in 63 consecutive outpatients from four Spanish hospitals. A total of 43 men and 20 women were included, with a median age of 67 years. In seven of the cases treatment with pleurodesis had failed; in five other cases their lung was trapped; in another five cases after repeat therapeutic thoracocentesis, and the rest of them as a preference choice to pleurodesis. All patients had an indwelling pleural catheter inserted (PleurX®, Denver Biomedical).ResultsMost of patients (94.5%) reported an improvement in their respiratory symptoms (cough and dyspnoea) and their ability to function independently. Average length of the catheterisation was 45 days (6-222). Average amount of drained pleural effusion was 75 ml, with a frequency of drainage of between 3 and 4 times per week and once fortnightly. Spontaneous pleurodesis was achieved following 34.9% of procedures. No complications occurred during the insertion of the catheter. The post-catheterisation complications were empyema (3 cases), chest pain (2 cases), and tumour metastasis (3 cases).ConclusionsThe use of an indwelling pleural catheter is an effective palliative treatment in the outpatient management for patients suffering malignant pleural effusion. It is also a simple treatment that can be easily applied, does not require hospitalisation and can be easily managed by the patient at home, with a low rate of complications. 相似文献