全文获取类型
收费全文 | 34194篇 |
免费 | 2676篇 |
国内免费 | 420篇 |
专业分类
耳鼻咽喉 | 359篇 |
儿科学 | 1010篇 |
妇产科学 | 608篇 |
基础医学 | 4947篇 |
口腔科学 | 517篇 |
临床医学 | 3212篇 |
内科学 | 7348篇 |
皮肤病学 | 760篇 |
神经病学 | 2584篇 |
特种医学 | 1289篇 |
外国民族医学 | 16篇 |
外科学 | 4177篇 |
综合类 | 1281篇 |
现状与发展 | 1篇 |
一般理论 | 2篇 |
预防医学 | 2672篇 |
眼科学 | 680篇 |
药学 | 2575篇 |
6篇 | |
中国医学 | 622篇 |
肿瘤学 | 2624篇 |
出版年
2023年 | 269篇 |
2022年 | 647篇 |
2021年 | 1082篇 |
2020年 | 673篇 |
2019年 | 839篇 |
2018年 | 1037篇 |
2017年 | 751篇 |
2016年 | 744篇 |
2015年 | 905篇 |
2014年 | 1155篇 |
2013年 | 1503篇 |
2012年 | 2178篇 |
2011年 | 2187篇 |
2010年 | 1350篇 |
2009年 | 1119篇 |
2008年 | 1612篇 |
2007年 | 1657篇 |
2006年 | 1585篇 |
2005年 | 1490篇 |
2004年 | 1327篇 |
2003年 | 1266篇 |
2002年 | 1197篇 |
2001年 | 1112篇 |
2000年 | 1100篇 |
1999年 | 977篇 |
1998年 | 343篇 |
1997年 | 299篇 |
1996年 | 262篇 |
1995年 | 211篇 |
1994年 | 208篇 |
1993年 | 174篇 |
1992年 | 516篇 |
1991年 | 499篇 |
1990年 | 474篇 |
1989年 | 432篇 |
1988年 | 452篇 |
1987年 | 381篇 |
1986年 | 372篇 |
1985年 | 365篇 |
1984年 | 255篇 |
1983年 | 187篇 |
1982年 | 119篇 |
1981年 | 103篇 |
1979年 | 210篇 |
1978年 | 111篇 |
1977年 | 124篇 |
1976年 | 113篇 |
1974年 | 130篇 |
1972年 | 128篇 |
1969年 | 104篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
72.
73.
Gil Bellis Marie-Hélène Cazes Alain Parant Maryse Gaimard Cécile Travers Evelyne Le Roux Sophie Ravilly Gilles Rault 《Journal of cystic fibrosis》2007,6(3):179-186
BACKGROUND: In 1992 France set up a national cystic fibrosis observatory (Observatoire national de la mucoviscidose, ONM) to monitor the state of health of patients on an annual basis. Using the ONM data, this study estimates the main indicators for life expectancy and assesses the total number of cystic fibrosis patients. METHODS: The data for the years 1994 to 2003 are divided into 3-year periods. Life tables are drawn up for these periods, from which mean and median lengths of life are determined. Using the most recent life table, the number of births in 2003 and the incidence of the disease, the total population of patients can be estimated, assuming a stationary population. RESULTS: In 2001-2003, life expectancy at birth of patients registered with the ONM was 39.1 years and median length of life was 36.4 years. These results, substantially better than those of 1994-1996, are linked to improved conditions of patient inclusion in the ONM database, to improvements in their healthcare, but also to the limitations of the life tables. Based on the 2003 data, the total theoretical number of patients is 6490, and coverage by the ONM database is thus 63.2%. CONCLUSIONS: These provisional results demonstrate the need to convert the ONM observatory into a registry providing exhaustive coverage of all patients. 相似文献
74.
R Bachmann B Genin P Bugmann D Belli S Hanquinet P Liniger C Le Coultre 《Zeitschrift für Kinderchirurgie》2003,13(4):280-284
Although benign, hepatic haemangioendotheliomas (HHE) are rare vascular tumours of the infant which have a high mortality rate secondary to high output congestive heart failure. The management of these tumours is still controversial and none of the different medical or surgical options has been unanimously accepted. We report the case of a neonate with congestive heart failure (CHF) due to a localized HHE, treated successfully by selective ligation of the left hepatic artery branch irrigating the tumour, under perioperative ultrasound Doppler control. A review of the literature showed 35 cases of HHE treated by hepatic artery ligation (HAL) with a survival rate of 80 %. 相似文献
75.
The cyclic vomiting syndrome is defined by episodes of vomiting lasting from hours to days with free intervals between episodes. Various symptoms can be associated with vomiting: nausea, abdominal pain, photophobia, fever, pallor, dehydratation, excess salivation, social withdrawal. Some factors often precipitate the crisis: infection, psychological stresses, menstruation. Excluding a medical condition, especially a gastro-intestinal or a neurological disease is compulsory for the diagnostic of cyclic vomiting syndrome. The cyclic vomiting syndrome shares many common features with migraine including treatment. Due to negative paraclinical testing, a psychiatric disease is often suspected in these children. Pathophysiology of cyclic vomiting syndrome is unknown. As for migraine, mitochondrial and ionic channels abnormalities are thought to play a role. Overactivation of hypothalamic-pituitary-adrenal axis and autonomic dysfunction seem to be involved too. Three clinical vignets will illustrate these aspects. 相似文献
76.
Effects of different cellulose derivatives on drug release mechanism studied at a preformulation stage. 总被引:2,自引:0,他引:2
O Chambin D Champion C Debray M H Rochat-Gonthier M Le Meste Y Pourcelot 《Journal of controlled release》2004,95(1):101-108
As a matter of fact, in vitro dissolution is well known to be the method of choice for the pharmaceutical industry to develop effective medicines. However, many experiments must be performed all along a new product life and they represent an overcharge of work for researchers. The purpose of this paper was to assess the relevance of new parameters obtained during preformulation stage by Nuclear Magnetic Resonance (NMR) experiments to better understand drug release mechanism. This study was carried out with three cellulose derivatives currently used as carrier matrices (Microcrystalline cellulose (MCC), Hydroxypropylmethyl cellulose (HPMC) and Ethyl cellulose (EC)). Granules and tablets were produced with these three excipients (60% w/w) and theophylline as drug model (40%). On the one hand, in vitro dissolution studies were performed with the rotating paddle method displaying the different release behaviour of these three matrices (immediate release for MCC, steady release for HPMC and sustained release for EC). On the other hand, the evolution of the T2m spin-spin relaxation time in NMR experiments during granules hydration was recorded. NMR findings shore up dissolution data, both depending on interactions between the matrix and water. NMR spectroscopy appears to be a valuable tool for obtaining, at an earlier stage of drug development, more information about drug release mechanism. 相似文献
77.
G G Varela A López-Loredo J F García León 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(1):127-130
BACKGROUND AND OBJECTIVE: We present the case of a female patient 29 years of age with antecedents of laparoscopic laser ablation for endometriosis, laparoscopic appendectomy, and umbilical hernioplasty. METHODS: The patient was admitted to the hospital's emergency room for abdominal pain in the epigastrium, transfixing, irradiating to both upper quadrants and to the lumbar region, accompanied by nausea and gastrobiliary vomiting. Lipase determination was 170 mg/dL. Other laboratory findings were normal. Plain abdominal films on the patient's admission were normal, and computed tomography (CT) showed data compatible with acute pancreatitis. Without improvement during the patient's hospital stay, pain and vomiting increased in intensity and frequency. RESULTS: New abdominal x-rays revealed dilatation of small bowel loops. Management was begun for intestinal obstruction, with intravenous hydration and placement of a nasogastric tube without a good response. At 48 hours, a diagnostic laparoscopy was performed, revealing a 3-cm internal hernia in the left broad ligament in which a 20-cm segment of terminal ileum was encased. We performed liberation of the ileal segment and closed the hernial orifice by using the laparoscopic approach. CONCLUSION: The patient's evolution was excellent. 相似文献
78.
Thellea K. Leveque Le Yu David C. Musch Ronald D. Chervin David N. Zacks 《Sleep & breathing》2007,11(4):253-257
Patients with obstructive sleep apnea (OSA), in comparison to controls, have increased levels of circulating epinephrine and
norepinephrine, both of which are risk factors for the development of central serous chorioretinopathy (CSCR). The aim of
this pilot study was to investigate the frequency of symptoms that suggest OSA in CSCR patients and normal controls. The Berlin
Questionnaire, a validated research tool to assess risk for OSA, was administered to 29 patients who met the criteria for
active, acute, non-steroid-induced CSCR and 29 controls matched for age and sex. In this retrospective case-controlled study,
the main outcome measure was increased risk for OSA. The mean age of the patients was 47.8 years (range 29–72) and the mean
age of controls was 47.3 years (range 25–70). Seventy-six percent (22) of both groups were men. Survey scores showed 58.6%
(17) of patients with CSCR to be at an increased risk for OSA compared to 31.0% (nine) of controls. A conditional logistic
regression analysis showed that the CSCR group had a higher proportion with an increased risk for OSA compared to the control
group (odds ratio=3.67; 95% CI: 1.02, 13.14; P = 0.046). Patients with CSCR may be more likely than other adults to have OSA, and screening for this sleep disorder should
be considered in this population. Further research is warranted to determine whether sleep apnea may contribute to the development
of CSCR, and to assess whether treatment of sleep apnea might offer a new therapeutic option for some patients with CSCR. 相似文献
79.
80.