全文获取类型
收费全文 | 392942篇 |
免费 | 25639篇 |
国内免费 | 3830篇 |
专业分类
耳鼻咽喉 | 5308篇 |
儿科学 | 8350篇 |
妇产科学 | 10237篇 |
基础医学 | 54671篇 |
口腔科学 | 11955篇 |
临床医学 | 31937篇 |
内科学 | 80253篇 |
皮肤病学 | 8639篇 |
神经病学 | 27932篇 |
特种医学 | 14358篇 |
外国民族医学 | 92篇 |
外科学 | 62014篇 |
综合类 | 12967篇 |
现状与发展 | 7篇 |
一般理论 | 65篇 |
预防医学 | 18279篇 |
眼科学 | 9763篇 |
药学 | 32497篇 |
16篇 | |
中国医学 | 3089篇 |
肿瘤学 | 29982篇 |
出版年
2021年 | 3393篇 |
2020年 | 2267篇 |
2019年 | 3182篇 |
2018年 | 4956篇 |
2017年 | 3857篇 |
2016年 | 3962篇 |
2015年 | 4656篇 |
2014年 | 6493篇 |
2013年 | 8091篇 |
2012年 | 11102篇 |
2011年 | 11361篇 |
2010年 | 7006篇 |
2009年 | 6485篇 |
2008年 | 10220篇 |
2007年 | 11042篇 |
2006年 | 10971篇 |
2005年 | 10000篇 |
2004年 | 9240篇 |
2003年 | 8937篇 |
2002年 | 8566篇 |
2001年 | 28551篇 |
2000年 | 29045篇 |
1999年 | 23920篇 |
1998年 | 5344篇 |
1997年 | 4440篇 |
1996年 | 3986篇 |
1995年 | 3608篇 |
1994年 | 3206篇 |
1993年 | 2899篇 |
1992年 | 16119篇 |
1991年 | 14878篇 |
1990年 | 14224篇 |
1989年 | 14016篇 |
1988年 | 12615篇 |
1987年 | 12092篇 |
1986年 | 11142篇 |
1985年 | 10336篇 |
1984年 | 6919篇 |
1983年 | 5605篇 |
1982年 | 2724篇 |
1979年 | 5481篇 |
1978年 | 3347篇 |
1977年 | 2971篇 |
1975年 | 2641篇 |
1974年 | 3064篇 |
1973年 | 2865篇 |
1972年 | 2828篇 |
1971年 | 2773篇 |
1970年 | 2510篇 |
1969年 | 2543篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
The present review analyzes the accumulated data from all cases of glandular odontogenic cyst (GOC) reported in the English language literature. In the 20 years since it was first described, 111 cases have been reported, an incidence of 0.2% of odontogenic cysts. The age range is 14-75, mean 45.7, with a M/F ratio of 1.3:1. GOC has a predilection for the mandible (70%), affecting both anterior and posterior areas. It is typically radiolucent, well defined, either unilocular (53.8%) or multilocular (46.2%). Frequent perforation (61%) and of thinning of cortical plates (24.4%) indicate aggressiveness. Sufficient follow-up indicates that 30% of cases can recur. Treatment by enucleation or curettage carries the highest risk for recurrence, especially in large and multilocular lesions. Peripheral osteoectomy or marginal resection can eliminate the risk. Defined criteria for microscopic diagnosis are described, which in addition to Ki67 and p53 can help in differentiating GOC from lesions with histological similarities (cysts with mucous metaplasia, botryoid and surgical ciliated cysts, low-grade mucoepidermoid carcinoma). Definite diagnosis may not be possible in small incisional biopsies due to the focal presentation of characteristic features required for diagnosis. There is now evidence to support an odontogenic rather than a sialogenic origin. 相似文献
93.
Kokubo Y Tsumita M Sakurai S Torizuka K Vult von Steyern P Fukushima S 《Journal of oral rehabilitation》2007,34(7):503-507
This study evaluated the fracture loads of three-unit all-ceramic bridges on implants; the core frameworks of the bridges were made of zirconium oxide. Three core framework designs were fabricated according to the design of the bars between the retainers: (i) straight, (ii) curved in the occlusal direction, or (iii) curved in the gingival direction. A static load was applied at the centre of the pontic, and the mean initial crack and final fracture loads were measured and compared. The core framework curved in the occlusal direction had the highest final fracture loads; there were significant differences (P < 0.05) in the mean final fracture load, whereas initial fracture load, which fractured of veneered porcelain, did not show significant differences among three designs. The all-ceramic bridges on the implants made with Procera zirconium core frameworks had high final fracture load. The core framework design that curved in the occlusal direction helped the framework withstand the occlusal load, which results in reliable prostheses, especially in the molar region. 相似文献
94.
Deng M Dong H Long X Li X Cheng Y 《International journal of oral and maxillofacial surgery》2007,36(8):752-755
Endoscopy is widely used in the diagnosis and treatment of temporomandibular joint disorders. This paper introduces arthro-endoscopy as a new method of treatment for temporomandibular joint dislocation. As this method is minimally invasive, it is suitable for medically compromised patients who cannot tolerate open surgery. 相似文献
95.
96.
A growing number of patients go to orthodontic practices to receive orthodontic re-treatment, but their reasons for seeking re-treatment are uncertain. By means of a standardized questionnaire this study investigates the patients'experiences with the initial orthodontic treatment, applied retention procedures, and the patients'expectations and motivational reasons for re-treatment. In total 100 patients were asked to complete the questionnaire, 88 of them actually filled it out. The study subjects showed an above average educational level, with a considerably higher percentage of females than males seeking re-treatment. Fixed appliances were used most frequently during the first course of treatment and most patients had been fitted with a removable retention plate or fixed retention wire at the conclusion of their first treatment; almost 40% of the patients did not receive any kind of retention appliance. Patients sought re-treatment mostly on their own initiative, as opposed to their initial treatment, when they were mostly referred by dentists or orthodontists. This revealed itself in patients' high levels of motivation for re-treatment. Moreover, patients appeared to have realistic impressions of the time and cost involved in re-treatment. 相似文献
97.
Association between periodontal pockets and elevated cholesterol and low density lipoprotein cholesterol levels 总被引:3,自引:0,他引:3
BACKGROUND: Periodontitis is associated with increased prevalence of cardiovascular morbidity and mortality; however, the nature of this association is unclear. There is a rationale that indicates that the presence of periodontal pockets which can harbor pathogenic microorganisms and evoke a host response could elicit a systemic effect. The hypothesis of this study is that periodontal pockets may be associated with elevated blood lipid levels, a known risk factor for atherosclerotic disease. METHODS: The periodontal health of 10,590 Israeli military service men and women was assessed using the Community Periodontal Index of Treatment Needs (CPITN). The relationship of blood lipids and periodontal disease and CPITN index was tested, controlling for factors that are related to elevated cholesterol levels, including high body mass index (BMI), age, diastolic blood pressure, and smoking. RESULTS: The presence of periodontal pockets was positively associated with higher cholesterol and low density lipoprotein (LDL) cholesterol blood levels in men. No significant association was found in women. CONCLUSIONS: In this large cohort study, the presence of periodontal pockets as measured by CPITN was positively associated with total cholesterol and LDL-cholesterol. The findings of the study support the reports linking increased prevalence of cardiovascular mortality among patients with periodontal disease. 相似文献
98.
Porphyromonas gingivalis has been shown to attack host defense systems through proteolytic cleavage of a wide variety of members of the systems. In this study, we examined the ability of P. gingivalis culture supernatant to alter the expression of human T cell surface proteins. As judged by flow cytometric analysis, detection of CD4 expression was completely eliminated by the supernatant, but CD8 was less sensitive. When the culture supernatant was added with reducing agents, proteolytic activity was enhanced, resulting in the cleavage of CD8. Mitogenic response of T cells to phytohemagglutinin or concanavalin A was decreased by the treatment of the cells with the culture supernatant of P. gingivalis. The three forms of gingipains (high molecular mass arginine-specific gingipain, arginine-specific gingipain 2 and lysine-specific gingipain) purified from the culture supernatant of P. gingivalis actively cleaved CD4 and CD8 on human T cells, indicating that proteolytic activity of the culture supernatant was due to gingipains. These results suggest that cysteine proteinases like gingipains released from P. gingivalis cleave T cell surface proteins and impede T cell function. 相似文献
99.
Natsume N Niimi T Furukawa H Kawai T Ogi N Suzuki Y Kawai T 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2001,91(2):157-161
There have been many reports on congenital anomalies associated with cleft lip and/or palate (CL/CLP) in Japan. However, these reports included data only on patients who came to hospitals; thus the real situation regarding these anomalies remains unclear. Therefore, we surveyed newborns at all delivery facilities in the central area of Japan for the presence of these anomalies, following their progress for 12 consecutive years; at the end of that time, questionnaires were collected and analyzed. In this article, we describe our results. 相似文献
100.
Ogawa T Kitagawa Y Ogasawara T 《International journal of oral and maxillofacial surgery》2001,30(2):176-178
A rare case of neurinoma in a 72 year-old Japanese woman derived from the hypoglossal nerve is reported. The tumour was composed of three interconnected nodules occurring simultaneously in the left submandibular and sublingual regions. The lesion, which presented as a neck mass, caused a slight left-sided hemiparesis of the tongue with tongue deviation to the affected side not noticed by the patient. An electromyographic (EMG) study revealed decreased muscle activity on the left side of the tongue muscle, indicating dysfunction of the hypoglossal nerve. EMG was useful for diagnosis. 相似文献