全文获取类型
收费全文 | 44067篇 |
免费 | 5164篇 |
国内免费 | 1059篇 |
专业分类
耳鼻咽喉 | 455篇 |
儿科学 | 580篇 |
妇产科学 | 672篇 |
基础医学 | 5451篇 |
口腔科学 | 10814篇 |
临床医学 | 3137篇 |
内科学 | 5866篇 |
皮肤病学 | 914篇 |
神经病学 | 1848篇 |
特种医学 | 493篇 |
外国民族医学 | 2篇 |
外科学 | 2655篇 |
综合类 | 3669篇 |
现状与发展 | 10篇 |
预防医学 | 2244篇 |
眼科学 | 753篇 |
药学 | 6231篇 |
55篇 | |
中国医学 | 2326篇 |
肿瘤学 | 2115篇 |
出版年
2024年 | 639篇 |
2023年 | 1167篇 |
2022年 | 1687篇 |
2021年 | 2340篇 |
2020年 | 2320篇 |
2019年 | 2248篇 |
2018年 | 2092篇 |
2017年 | 2055篇 |
2016年 | 2075篇 |
2015年 | 2119篇 |
2014年 | 2633篇 |
2013年 | 4227篇 |
2012年 | 2231篇 |
2011年 | 2373篇 |
2010年 | 1916篇 |
2009年 | 1838篇 |
2008年 | 1798篇 |
2007年 | 1750篇 |
2006年 | 1568篇 |
2005年 | 1425篇 |
2004年 | 1268篇 |
2003年 | 1078篇 |
2002年 | 956篇 |
2001年 | 807篇 |
2000年 | 641篇 |
1999年 | 572篇 |
1998年 | 512篇 |
1997年 | 498篇 |
1996年 | 414篇 |
1995年 | 351篇 |
1994年 | 309篇 |
1993年 | 268篇 |
1992年 | 259篇 |
1991年 | 198篇 |
1990年 | 173篇 |
1989年 | 190篇 |
1988年 | 149篇 |
1987年 | 137篇 |
1986年 | 120篇 |
1985年 | 114篇 |
1984年 | 112篇 |
1983年 | 88篇 |
1982年 | 89篇 |
1981年 | 95篇 |
1980年 | 71篇 |
1979年 | 51篇 |
1978年 | 46篇 |
1977年 | 66篇 |
1976年 | 48篇 |
1975年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Matrix metalloproteinase-8 (MMP-8) in pulpal and periapical inflammation and periapical root-canal exudates 总被引:4,自引:0,他引:4
Wahlgren J Salo T Teronen O Luoto H Sorsa T Tjäderhane L 《International endodontic journal》2002,35(11):897-904
AIM: To study the presence, levels and molecular forms of matrix metalloproteinase (MMP) -8 (collage-nase-2) in pulpal and periapical inflammation, and the changes in MMP-8 levels in root-canal exudates during root-canal treatment. METHODOLOGY: Periapical exudate samples were collected from 11 necrotic teeth with radiographically verified periapical periodontitis during three root-canal treatment visits with interappointment calcium hydroxide (Ca(OH)2) medication. MMP-8 levels and molecular forms were analyzed with immunofluorescent assay (IFMA) and Western immunoblot. Inflamed pulp tissue and periapical granuloma tissue (n = 10 for both) were obtained from other patients and used for MMP-8 immunohistochemical (IHC) staining. RESULTS: The periapical exudate samples demonstrated marked differences in MMP-8 levels between the teeth in the first visit and significant decrease in MMP-8 levels during the root-canal treatment (P = 0.0107). One specimen failed to show a decrease in MMP-8 below 1000 ng mL(-1) a vertical root fracture was later diagnosed and the tooth extracted. IHC staining showed that in addition to PMN-leucocytes, macrophages and plasma cells produced MMP-8 in pulp and periapical granulomas. CONCLUSIONS: The findings demonstrate the presence of MMP-8 in the inflamed pulp and periapical tissue, indicating that MMP-8 has a role in pulpal and periapical inflammation, most likely participating in tissue extracellular matrix degradation. They further indicate that MMP analysis from periapical exudate could be used to indicate and monitor inflammatory activity and the success of treatment in teeth with periapical lesions. 相似文献
52.
The aim of this study was to describe and compare salivary immunoglobulin A (IgA) antibody reactions to extracts of strains of three oral streptococci in human leukocyte antigen (HLA)-DR4-positive and -DR4-negative subjects. Whole paraffin-stimulated saliva samples were collected from 27 apparently healthy subjects. Previous HLA typing showed that 20 subjects were DR4 positive and 7 were DR4 negative. HLA-DRB1*04 subtyping was performed among the DR4-positive subjects. Whole-cell antigen extracts from Streptococcus mutans (KPSK 2), Streptococcus sobrinus (OMZ 65) and Streptococcus parasanguis (Nt 62) were separated in SDS-PAGE. The antigens were immunoblotted with diluted saliva (Western blot), scanned and analyzed in a computer system. All immunoblot bands were recorded in DR4-positive and DR4-negative saliva pools, and bands with an optical density >or=0.1 were selected for analysis in individual salivas. The DR4-negative subjects in general had more immunoblot bands and more distinct bands than did the DR4-positive subjects. A higher concentration of total IgA in saliva was correlated with more bands, especially to antigens separated from S. mutans. When the number of bands was calculated per IgA unit, significant differences were observed between DR4-positive and DR4-negative salivas. This was particularly seen for S. mutans and S. parasanguis. As the number of bands was analyzed in relation to DR4 subgroups, DRB1*04, there was a lower salivary IgA activity to S. mutans in the DRB1*0401 and *0404. The variable level of correlation previously demonstrated for S. mutans colonisation and serologically defined DR4 positive subjects might be explained by the heterogeneity in this group, and the relation should be sought on a subgroup level. 相似文献
53.
OBJECTIVE: To discuss the determinants for the possible setting of global goals for oral health for the year 2010. RESULTS AND CONCLUSIONS: If the application of oral health goals is to measure the outcome of oral health strategies and plans, they need to be substantially redesigned to reflect disparities in oral health and access to oral health care. It is no longer acceptable to focus only upon one or two arbitrarily selected disease entities and say these reflect the oral well-being of communities and the success (or failure) of oral health programmes. The use of validated socio-dental indicators to assess prevalence of socio-dental impacts seems essential, as does the avoidance of goals for conditions that are strongly influenced by culture, class, ethnicity and other widely variable local influences. 相似文献
54.
OBJECTIVES: To characterise lymphoid follicle-like aggregates incidentally found to occur in biopsies of oral lichenoid reactions (OLR) and to correlate the findings to hyperplastic tonsil follicles.
DESIGN: An immunocytochemical analysis of archival material.
SUBJECTS AND METHODS: In an arbitrarily selected period 1992–1994 with a total of 13 924 oral biopsies, 2407 cases were signed out as OLR or lichen planus. These were microscopically reviewed, with the purpose to retrieve all cases showing histologic changes resembling secondary lymphoid follicles.
RESULTS: 87 cases showed lymphoid follicle-like changes and 82 of these were in oral regions known to constitut-ively lack 'organised MALT'. Unexpectedly, all of the 82 were found retrospectively to be in close or direct contact with amalgam fillings. Immunocytochemically, using antibodies to B and T cells, macrophages, follicular dendritic cells and proliferation and apoptosis markers, the mucosal follicles stained similar to tonsillar secondary follicles. In several of an additional 11 OLR cases with histologic changes suggestive of primary follicles, we also found immunocytochemical evidence of such changes.
CONCLUSIONS: 'Tertiary lymphoid follicles' may occasionally develop in OLR at sites of the oral mucosa constitutively lacking organised lymphoid tissue. The microenvironment of the OLR T cell infiltrate may occasionally favour such follicle development and amalgam constituents may causally be involved in an unknown way. 相似文献
DESIGN: An immunocytochemical analysis of archival material.
SUBJECTS AND METHODS: In an arbitrarily selected period 1992–1994 with a total of 13 924 oral biopsies, 2407 cases were signed out as OLR or lichen planus. These were microscopically reviewed, with the purpose to retrieve all cases showing histologic changes resembling secondary lymphoid follicles.
RESULTS: 87 cases showed lymphoid follicle-like changes and 82 of these were in oral regions known to constitut-ively lack 'organised MALT'. Unexpectedly, all of the 82 were found retrospectively to be in close or direct contact with amalgam fillings. Immunocytochemically, using antibodies to B and T cells, macrophages, follicular dendritic cells and proliferation and apoptosis markers, the mucosal follicles stained similar to tonsillar secondary follicles. In several of an additional 11 OLR cases with histologic changes suggestive of primary follicles, we also found immunocytochemical evidence of such changes.
CONCLUSIONS: 'Tertiary lymphoid follicles' may occasionally develop in OLR at sites of the oral mucosa constitutively lacking organised lymphoid tissue. The microenvironment of the OLR T cell infiltrate may occasionally favour such follicle development and amalgam constituents may causally be involved in an unknown way. 相似文献
55.
Sklavounou-Andrikopoulou A Iakovou M Paikos S Papanikolaou V Loukeris D Voulgarelis M 《Oral diseases》2004,10(2):118-122
Papular-purpuric 'gloves and socks' syndrome (PPGSS) is a novel, rare, self-limited dermatosis initially described in 1990. It is characterized by painful, pruritic edema and erythema, rapidly evolving to papular-purpuric lesions on the distal extremities, in a gloves-and-socks distribution, accompanied by fever and oral lesions such as petechiae, vesiculopustules and small erosions. Parvovirus B19 has been implicated in most cases as the etiological factor. Herein we present the first case of PPGSS in a 42-year-old Greek man with von Willebrand disease. On admission the patient was febrile, and presented acral edema and erythema rapidly followed by purpuric lesions on the same sites, and palatal petechiae. Complete remission of the exanthem occurred 7 days after hospitalization. Clinical and laboratory evaluation including serologic tests and PCR, confirmed the presence of parvovirus B19. Review of the existing literature on this novel syndrome and its association with parvovirus B19 is also presented. 相似文献
56.
Oral Diseases (2011) 17 , 720–726 Background: Tobacco‐related oral squamous cell carcinoma (OSCC) is one of the most common cancers involving Indian males. We assessed the association of IL4 promoter –589 T>C, –33 T>C, and IL6–174 G>C functional genetic polymorphisms with tobacco‐related OSCC in Asian Indians. Patients and Methods: The IL4 and IL6 promoter polymorphisms were assessed in 140 patients with OSCC and 120 normal subjects by PCR–RFLP technique, and significance of the data was determined using chi‐square test. Results: The frequency of TC, CC genotype, and C allele at IL4 promoter sites –589 and –33 were higher in patients when compared with controls. Consequently, TC/CC genotypes and C allele at both sites appeared as susceptible. However, IL6–174 G>C single‐nucleotide polymorphisms (SNP) appeared to be protective in patients with OSCC. Of eight haplotypes, five were associated with two‐ to seven‐fold increased risk of tobacco‐related OSCC. These SNPs further showed heterogeneity among different ethnic population, but their distribution in Asian Indians stand closer to other Asian populations. Conclusions: In this study, IL4–589 CC, –33 CC genotype, and *C allele at both sites appeared to be susceptible, while IL6–174 CC genotype and *C allele appeared to be protective in patients with OSCC; hence, these SNPs may be a potential prognostic markers for tobacco‐related OSCC in Asian Indians. 相似文献
57.
Furuta M Ekuni D Irie K Azuma T Tomofuji T Ogura T Morita M 《Journal of periodontology》2011,82(4):558-565
Background: Although many epidemiologic surveys have shown that gingivitis is more prevalent in males than in females, few studies have clearly explained what causes this difference. The objective of the present study is to explain the sex difference in gingivitis based on the interaction between oral health behaviors and related factors, such as knowledge, attitude, and lifestyle, in young people. Methods: The study was comprised of 838 subjects (440 males and 398 females), aged 18 and 19 years. Gingivitis was assessed by the percentage of bleeding on probing (%BOP). Additional information was collected regarding oral hygiene status, oral health behaviors, and related factors. Structural equation modeling was used to test pathways from these factors to %BOP. Multiple‐group modeling was also conducted to test for sex differences. Results: Females had greater knowledge, a more positive attitude, a healthier lifestyle, and higher level of oral health behaviors than males. There were significant differences in the paths (i.e., from lifestyle, knowledge, and attitude to %BOP) through oral health behaviors and oral health status. Conclusions: Sex‐based differences in gingivitis in young people can be explained by oral health behaviors and hygiene status, which are influenced by lifestyle, knowledge, and attitude. To prevent gingivitis, different approaches to males and females may be useful. 相似文献
58.
Chieko Ishikawa Yuko Shigeta Takumi Ogawa Shinya Hirai Eriko Ando Tomoko Ikawa Shintaro Kasama Keisuke Ihara Noboru Kawamura Yukihiro Mizuno Shunji Fukushima Toshio Hosoi Jun Nejima C. Ohkubo 《Journal of Indian Prosthodontic Society》2010,10(1):57-63
Background
Oral appliance (OA) therapy for obstructive sleep apnea (OSA) has only been part of Japan’s National Health care coverage plan since 2004. Subsequently, not enough time has passed to establish the medical trends and characteristics of OSA patients in Japanese Dental Hospitals.Aim
The aim of this study was to investigate the medical trends and the characteristics in patients with OSA who visited our clinic, and to compare our findings with previous studies.Setting and design
Epidemiological survey (retrospective study).Materials and methods
Two hundred and one patients were recruited at the Internal Medicine Division in the Tsurumi University Dental Hospital from February 2006 to December 2008, consecutively. Patients received a medical interview, and a detailed sleep analysis that included a polysomnography (PSG) to verify the exact nature of their condition. The efficacy of OA was assessed in 49 patients who wore an OA and underwent PSG.Results
Of all subjects, 141 patients visited the Prosthodontic Division to receive OA therapy, 38 patients were treated or received a follow up examination in the Internal Medicine Division. The dropout rate was 10.4% in the all subjects, 17.0% in patients who visited the Prosthodontic Division. The male-to-female ratio was 3.3:1, 3.0:1 in patients who visited the Prosthodontic Division. In addition, females had a lower rate of OAS severity than males. In our patients, the major complication was hypertension and cardiac disease. The success rate of OA was 75.5%.Conclusion
This approach allowed us to reveal some of the trends and characteristics in our patients. 相似文献59.
Denture stomatitis (chronic atrophic candidosis) is a very common complication to the wearing of complete dentures. The infection is due to a contamination of the denture by yeasts. In a number of studies the clinical effect of Hibitane when used as a denture disinfectant has been studied. It was found that Hibitane (0.2--2%) caused a significant amelioration of inflamed palatal tissues and a reduction in the number of yeast cells harbored on the palatal mucosa and the fitting surface of the dentures. However, relapse of the infection was frequent after treatment was sustained. It was concluded that Hibitane could not be recommended for routine denture disinfection, first, because it caused staining of the dentures, second, because of the relative resistance of the yeast to the action of the drug. However, it seems justified to use Hibitane prophylactically as a denture disinfectant in patients who are highly susceptible to developing disseminating or systemic candidosis. Hibitane is a valuable drug in the treatment of denture stomatitis when used as a denture disinfectant. 相似文献
60.
正畸儿童龋病的口腔综合防治 总被引:4,自引:0,他引:4
目的:观察口腔综合防治措施对正畸儿童龋病的作用。方法:以56名12-16岁的正畸患者为观察对象,观察矫治前、矫治后半年及1年的龋指数、变形链球菌计数、乳酸杆菌计数的改变。实验组采用口腔综合保健措施。结果:实验组的变形链球菌计数、乳酸杆菌计数明显低于对照组,差异有显著性;实验组无新龋发生,对照组龋均比实验组有所上升,但两组之间无统计学上的差异。结论:正畸治疗患者龋病通过口腔综合防治措施是可以治疗和预防的。 相似文献