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31.
改进Trizol法提取白色念珠菌总RNA初探 总被引:2,自引:0,他引:2
潘 《临床口腔医学杂志》2007,23(9):531-533
目的:比较Trizol法、改进Trizol法和超声粉碎法提取白色念珠菌总RNA产量、纯度和完整性的差异。方法:对生长至静止期的白色念珠菌标准株ATCC10231分别采用Trizol法、改进Trizol法和超声粉碎法提取总RNA,用紫外分光光度计测量其A260,A280的值,并进行琼脂糖凝胶电泳,对总RNA的产量、纯度和完整性进行比较。结果:三种方法提取白色念珠菌总RNA产量分别为1.904μg、7.208μg和5.000μg,A260/A280比值分别为1.896、1.415和1.612。电泳结果显示改进Trizol法提取的总RNA呈现28 s rRNA,18 s rRNA和5 s rRNA三条清晰的条带,而Trizol法和超声粉碎法提取的总RNA均有降解。结论:改进Trizol法提取的白色念珠菌总RNA产量及纯度均高于Trizol法和超声粉碎法,且完整性更好。该法优于Trizol法和超声粉碎法。 相似文献
32.
OBJECTIVE: To investigate the expression of interleukin-1alpha (IL-1alpha), IL-1ra and IL-8 by the oral epithelium challenged by various Candida species. MATERIALS AND METHODS: In vitro candidiasis was induced by C. albicans wild type SC5314, its EFG1, CPH1 and secretory aspartyl proteinase (SAP) mutants and, ATCC isolates of C. albicans, C. tropicalis and C. dubliniensis using a reconstituted human oral epithelium (RHOE) model. IL-1alpha, IL-1ra and IL-8 levels in culture media were quantified by an enzyme-linked immunosorbent assay at 12, 24 and 48 h. Fungal invasion and IL-1ra expression in RHOE were detected by periodic acid-Schiff staining and immunohistochemistry. RESULTS: Overall, the invasive Candida induced relatively higher levels of IL-1alpha, IL-1ra and IL-8 in the culture media than the noninvasive isolates. IL-1alpha and IL-1ra levels induced by Candida with hyphal invasion were significantly higher (P < 0.05) than those induced by the isolates without hyphal invasion at 12, 24 and 48 h. Candida albicans SC5314 induced IL-1ra expression in RHOE at 12 and 24 h but not at 48 h consistent with its hyphal invasion; while the noninvasive mutants and non-albicans Candida induced IL-1ra expression at 48 h. CONCLUSIONS: The cytokine expression profiles in experimental oral candidiasis may be associated with the invasive potential of Candida. 相似文献
33.
de Carvalho FG Silva DS Hebling J Spolidorio LC Spolidorio DM 《Archives of oral biology》2006,51(11):1024-1028
This study determined the presence of mutans streptococci and Candida spp. in supragingival dental plaque and infected dentine of caries-free children, with early childhood caries and caries. Pooled samples of dental plaque and infected dentine were collected from 56 children aged 1-5 years, which were divided into 3 groups: early childhood caries (ECC); caries and caries-free. Infected dentine was collected in ECC and caries groups to compare the frequency of these microorganisms in the collected sites. The samples were inoculated in SB20 and SA medium, for mutans streptococci and Candida spp., respectively, and incubated at 37 degrees C for 48 h. Colony growth was verified and the identification was performed by biochemical tests and CHROMagar Candida. Fisher's test or chi-square (chi(2)) were applied (p=0.05). The more prevalent species were S. mutans and Candida albicans in ECC (85.4% and 60.4%, respectively), independently of the sample site. S. mutans only was significantly associated with carious teeth, whether in early childhood caries or not. However, the frequency of C. albicans in ECC was higher when compared to caries and caries-free groups. There is a significant association between the presence of C. albicans and early childhood caries. 相似文献
34.
目的 研究白假丝酵母菌(S.albicans)对人脐静脉内皮细胞株ECV304细胞增殖及细胞周期的影响.方法 体外培养ECV304,实验分为S.albicans上清液组、S.albicans灭活菌液组、上清液和灭活菌液混合组、对照组.采用MTT法、细胞计数法、倒置显微镜及流式细胞术分别观察各组对ECV304细胞增殖及细... 相似文献
35.
Vitkov L Krautgartner WD Hannig M Weitgasser R Stoiber W 《Oral microbiology and immunology》2002,17(1):60-64
Inflamed oral mucosa biopsies from patients with thrush and high candidal density were observed in a transmission electron microscope (TEM) using ultra-histochemical staining with ruthenium red for glycocalyx visualization. Fimbriae comprising the glycocalyx and enabling yeast adhesion to epithelial cells were clearly visualized by ruthenium red. All internalized portions of the yeast walls were devoid of glycocalyx, indicating that the growing tips of the hyphae mechanically penetrated the host cells. The attachment of Candida occurred in two ways: by fimbria-mediated adhesion enabling colonization of the epithelial surface, and by invasion of the superficial epithelial cells via hyphae. As the interaction between adhesin receptors and adhesins stimulates the production of proinflammatory cytokines, Candida adhesion itself is assumed to induce mucosal inflammation. 相似文献
36.
Candidal carriage and plaque distribution before, during and after removable orthodontic appliance therapy 总被引:1,自引:0,他引:1
Candidal counts at 6 mucosal sites in 33 subjects were estimated by imprint culture before, during and after removable orthodontic appliance therapy. Additionally, dental plaque scores and salivary pH were measured at each stage. Whole mouth and site prevalence of candida rose significantly during therapy before falling to levels approximating initial values. A similar pattern was seen for candidal counts for the whole mouth and at individual mucosal sites, although post-treatment densities were usually lower than originally seen. The number of sites colonised by candida and salivary pH also increased significantly during treatment and fell significantly afterwards. Only the upper palatal plaque scores rose during therapy and most other dental sites showed a gradual decrease in value during the course of the study. This could be attributed to regular monitoring of the patient's oral hygiene procedures. This investigation demonstrated a direct relationship between the presence of an acrylic appliance, candida and low salivary pH levels. Furthermore, removable appliance therapy had a positive, though transient influence upon the prevalence and density of oral candidal carriage, suggesting that the appliance may initiate the carrier state. 相似文献
37.
Marcia Carneiro Valera Katy Costa Godinho da Silva Lilian Eiko Maekawa Cláudio Antonio Talge Carvalho Cristiane Yumi Koga-Ito Carlos Henrique Ribeiro Camargo Raphael Silva e Lima 《Journal of applied oral science : revista FOB》2009,17(6):555-559
Objective:
The purpose of this study was to evaluate the action of sodium hypochlorite (NaOCl) associated with an intracanal medication against Candida albicans and Enterococcus faecalis inoculated in root canals.Material and Methods:
Thirty-six human single-rooted teeth with single root canals were used. The canals were contaminated with C. albicans and E. faecalis for 21 days and were then instrumented with 1% NaOCl. The roots were divided into 3 groups (n=12) according to the intracanal medication applied: calcium hydroxide paste, 2% chlorhexidine (CHX) gel, and 2% CHX gel associated with calcium hydroxide. The following collections were made from the root canals: a) initial sample (IS): 21 days after contamination (control), b) S1: after instrumentation, c) S2: 14 days after intracanal medication placement; S3: 7 days after intracanal medication removal. The results were analyzed statistically by the Kruskal-Wallis test at 5% significance level.Results and Conclusions:
Both 1% NaOCl irrigation and the intracanal medications were effective in eliminating E. faecalis and C. albicans inoculated in root canals. 相似文献38.
Camila Andrade Zamperini Carlos Eduardo Vergani Eunice Terezinha Giampaolo 《Archives of oral biology》2010,55(10):763-770
The adhesion of Candida albicans to surfaces is the prerequisite for occurrence of denture stomatitis.
Objective
Hence, this study investigated if surface modifications with plasma treatments could reduce the adherence of C. albicans to a denture base resin.Methods
Specimens (n = 180) with roughened and smooth surfaces were made and divided into five groups: control—specimens were left untreated; experimental groups—specimens were submitted to plasma treatments to obtain surfaces with different hydrophobicity (Ar/50 W; ArO2/70 W; AAt/130 W) or incorporation of fluorine (Ar/SF670 W). Contact angle measurements were performed immediately after the treatments and after immersion in water for 48 h. For each group, half of the specimens were incubated with saliva prior to the adhesion assay. The number of adherent yeasts was evaluated by XTT reduction method.Results
For the experimental groups, there was significant change in the mean contact angle after 48 h of immersion in water. Groups ArO2/70 W and ArSF6/70 W showed significantly lower absorbance readings than the other groups, regardless the presence or absence of saliva and surface roughness.Conclusions
Results demonstrated that ArO2/70 W and ArSF6/70 W plasma treatments showed promising potential for reducing the adherence of C. albicans to denture base resins. 相似文献39.
Shruti Vidhawan Agarwalla Kassapa Ellepola Mariana Caldeira Ferraz da Costa Guilhermino José Macêdo Fechine Julien Luc Paul Morin A.H. Castro Neto Chaminda Jayampath Seneviratne Vinicius Rosa 《Dental materials》2019,35(3):403-413
Objective
To evaluate the surface and wettability characteristics and the microbial biofilm interaction of graphene coating on titanium.Methods
Graphene was deposited on titanium (Control) via a liquid-free technique. The transfer was performed once (TiGS), repeated two (TiGD) and five times (TiGV) and characterized by AFM (n = 10), Raman spectroscopy (n = 10), contact angle and SFE (n = 5). Biofilm formation (n = 3) to Streptococcus mutans, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans was evaluated after 24 h by CV assay, CFU, XTT and confocal microscopy. Statistics were performed by one-way Anova, Tukey’s tests and Pearson’s correlation analysis at a pre-set significance level of 5 %.Results
Raman mappings revealed coverage yield of 82 % for TiGS and ≥99 % for TiGD and TiGV. Both TiGD and TiGV presented FWHM > 44 cm?1 and ID/IG ratio < 0.12, indicating multiple graphene layers and occlusion of defects. The contact angle was significantly higher for TiGD and TiGV (110° and 117°) comparing to the Control (70°). The SFE was lower for TiGD (13.8 mN/m) and TiGV (12.1 mN/m) comparing to Control (38.3 mN/m). TiGD was selected for biofilm assays and exhibited significant reduction in biofilm formation for all microorganisms compared to Control. There were statistical correlations between the high contact angle and low SFE of TiGD and decreased biofilm formation.Significance
TiGD presented high quality and coverage and decreased biofilm formation for all species. The increased hydrophobicity of graphene films was correlated with the decreased biofilm formation for various species. 相似文献40.