全文获取类型
收费全文 | 156928篇 |
免费 | 8029篇 |
国内免费 | 146篇 |
专业分类
耳鼻咽喉 | 2549篇 |
儿科学 | 5478篇 |
妇产科学 | 3901篇 |
基础医学 | 23549篇 |
口腔科学 | 5554篇 |
临床医学 | 13089篇 |
内科学 | 28180篇 |
皮肤病学 | 4263篇 |
神经病学 | 16116篇 |
特种医学 | 6557篇 |
外科学 | 23695篇 |
综合类 | 707篇 |
一般理论 | 44篇 |
预防医学 | 8984篇 |
眼科学 | 3291篇 |
药学 | 10606篇 |
中国医学 | 228篇 |
肿瘤学 | 8312篇 |
出版年
2023年 | 878篇 |
2022年 | 726篇 |
2021年 | 1582篇 |
2020年 | 1438篇 |
2019年 | 1762篇 |
2018年 | 3233篇 |
2017年 | 2766篇 |
2016年 | 3569篇 |
2015年 | 3166篇 |
2014年 | 3566篇 |
2013年 | 6063篇 |
2012年 | 7718篇 |
2011年 | 8619篇 |
2010年 | 4970篇 |
2009年 | 3683篇 |
2008年 | 8534篇 |
2007年 | 8972篇 |
2006年 | 8727篇 |
2005年 | 8721篇 |
2004年 | 8077篇 |
2003年 | 8125篇 |
2002年 | 7935篇 |
2001年 | 5699篇 |
2000年 | 6946篇 |
1999年 | 4217篇 |
1998年 | 1743篇 |
1997年 | 1449篇 |
1996年 | 1157篇 |
1995年 | 999篇 |
1994年 | 957篇 |
1993年 | 877篇 |
1992年 | 1378篇 |
1991年 | 1234篇 |
1990年 | 1262篇 |
1989年 | 1269篇 |
1988年 | 1118篇 |
1987年 | 1194篇 |
1986年 | 1022篇 |
1985年 | 1144篇 |
1984年 | 1037篇 |
1983年 | 864篇 |
1982年 | 755篇 |
1981年 | 720篇 |
1980年 | 648篇 |
1979年 | 788篇 |
1978年 | 655篇 |
1977年 | 640篇 |
1976年 | 565篇 |
1975年 | 603篇 |
1974年 | 606篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
Gastric cancer still represents the second most common cause of gastrointestinal cancers in Germany. A disturbing issue is that at the time of diagnosis there are less than 15% of patients for whom a cure can be achieved. Nowadays, biological, histomorphological, molecular genetic and epidemiological data suggest that Helicobacter pylori eradication may lead to the prevention of gastric pre-neoplastic lesions and even gastric cancer. At present, eradication can be offered to selected patients and populations at increased risk, but more research is required before embarking on general and global H. pylori eradication for gastric cancer prevention. The main challenge is to determine how long mucosal abnormalities remain reversible and gastric cancer development can be halted. 相似文献
23.
h. gregersen † ‡ § m. a. kwiatek ¶ w. schwizer ¶ & r. tutuian ¶ 《Neurogastroenterology and motility》2007,19(S1):47-61
Abstract Upper gastrointestinal (GI) symptoms occur frequently in the general population, making them among the most common indications responsible for patients consulting the healthcare system. Consequently, understanding and characterization of the upper GI symptoms is important for the diagnosis and assessment of organ dysfunction. In practice, assessment of clinical symptoms is difficult and it is still to a large extent unclear how sensitivity, volume and tone contribute to visceral perception in the upper GI tract. The goal of advanced research in upper GI symptoms is to obtain a better understanding of the mechanisms involved in transduction, transmission, and perception under normal and pathophysiological conditions. An important step towards this goal is understanding the information provided by and the inherent limitations of the currently available measuring techniques. This article focuses on the sensory testing of the oesophagus, and methods and concepts used to assess the relation between gastric volumes or tone and upper GI symptoms. It also summarizes the contributions of these techniques towards identifying the components responsible for the generation of upper GI symptoms. 相似文献
24.
25.
26.
Abstract – Traumatic dental injuries often occur to the teeth and their supporting tissues and they are the main reasons for emergency visit to a dental clinic. Management of a fracture depends on its position and the extent of root involvement. Horizontal root fractures are not seen frequently and the treatment consists of reduction and long‐term rigid fixation of the coronal segment. The present case demonstrates the successful management of two horizontally fractured maxillary central incisors with a follow‐up period of 9 months. 相似文献
27.
Endotracheal intubation is required in 5–10% of all prehospital emergencies. Poor environmental conditions (e.g. limited space, poor or excessive lighting etc.), unfavorable patient-related factors (e.g. trauma, bleeding, pulmonary aspiration etc.) and the pressure of time make prehospital airway management a challenging procedure even for experienced emergency physicians. The incidence of difficult endotracheal intubation is significantly higher than in-hospital. Profound clinical practice, recognition and adequate treatment of complications of intubation, and ongoing clinical practice are essential for successful and responsible prehospital airway management. A brief physical examination helps to identify predictors for difficult intubation, thereby modifying treatment strategies. Every emergency physician must be closely familiar with at least one supraglottic airway device and the recent algorithms to manage the unanticipated difficult airway. 相似文献
28.
Ohne Zusammenfassung 相似文献
29.
G Gunnlaugsson L Smedman M C da Silva M Grandien R Zetterstr?m 《Acta paediatrica Scandinavica》1989,78(1):62-66
One hundred and forty-four children aged 9-20 months living in 14 villages in a rural area of Guinea-Bissau were examined for circulating rotavirus antibodies twice in a 15-month period. An immunofluorescence technique was used. About 3/4 of the children seroconverted, independent of age on entering the study. The age-specific proportion of seropositivity increased from 4/40 (10%) at 9-11 months to 26/29 (90%) at 33-35 months of age. All the initially seropositive children retained detectable antibodies to rotavirus. The relative risk of seroconversion was 1.4 times (95% confidence interval 1.0-2.0) more common among children living in villages by the mainroad as compared to those living off the road. Contact rate is probably dependent on population density and mobility but not on age. Breast-feeding, decreasing sharply through the age interval covered by the follow-up (9-35 months), had no apparent influence on seroconversion at the ages concerned. 相似文献
30.
Hans-Peter Schlake Karl-Heinz Grotemeyer Ingolf Böttger Ingo Wilhelm Husstedt Günter Brune 《Neurosurgical review》1987,10(3):191-196
Migraine is considered to be a functional neurological disorder. In classical migraine (headache associated with prodromal visual field disturbances) and migraine accompagnée (headache associated with transient neurological symptoms), disturbances of cerebral blood flow and amine metabolism are thought to be pathogenetic factors. However, conventional methods of neuroimaging (CAT, NMR) usually do not yield any pathological findings in patients. Since 123I-iodoamphetamine (123I-IMP) crosses the intact blood brain barrier, 123I-IMP-SPECT is used for the assessment of cerebral perfusion in various neurological diseases, including functional disorders. 123I-IMP-SPECT was performed on 5 patients with classical migraine and 18 patients with migraine accompagnée. At the time of investigation, all patients were symptom-free. Cerebral blood flow was decreased in all patients with migraine accompagnée, and often corresponded to the site of headache as well as to the topography of transient neurological symptoms. This reduction was most obvious in a patient with persisting neurological symptoms. Most patients with classical migraine, however, did not show any alteration of cerebral perfusion. It appears that migraine--and in particular migraine accompagnée--is characterized by a permanent alteration not only of cerebral blood flow but also of neuronal activity. Migraine attacks may occur in connection with exacerbations of preexisting metabolic alterations. 相似文献