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31.
Clinical,Microbial, and Immune Responses Observed in Patients With Diabetes After Treatment for Gingivitis: A Three‐Month Randomized Clinical Trial 下载免费PDF全文
Suzane A. Raslan Jose R. Cortelli Fernando O. Costa Davi R. Aquino Gilson C.N. Franco Luis O.M. Cota Antonio Gargioni‐Filho Sheila C. Cortelli 《Journal of periodontology》2015,86(4):516-526
Background: Although patients with diabetes are frequently affected by periodontitis, only a few investigations have focused on gingivitis in this at‐risk population. This randomized placebo‐controlled clinical trial compared the response to a gingivitis treatment protocol that combined mechanical procedures and daily use of an essential oil (EO) mouthrinse between patients with and without diabetes. Methods: The whole‐mouth periodontal probing depth (PD), gingival index (GI), and plaque index (PI) were monitored in gingivitis cases among systemically healthy patients (n = 60) or those with diabetes (n = 60) at baseline and 3 months after treatment. Levels of Porphyromonas gingivalis, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and total bacterial load were determined by a real‐time polymerase chain reaction in intrasulci plaque samples. The volume of gingival crevicular fluid (GCF) was quantified, and interleukin‐1β (IL‐1β) levels were determined in GCF samples. After a full‐mouth ultrasonic debridement, patients were randomly assigned to an EO or a placebo rinse for 90 days (40 mL/day). The data were analyzed through repeated‐measures analysis of variance and multiple comparisons Tukey tests (P <0.05). Results: GI was more severe in the diabetes group. Diabetes impaired GI and reduced GCF volume. PD, bacterial levels, and IL‐1β improved similarly in both systemic conditions. The adjunctive use of EO provided greater reductions of PI, GI, total bacterial load, T. forsythia, A. actinomycetemcomitans, and GCF volume. Conclusions: Response to gingivitis treatment in patients with diabetes can slightly differ from that in patients without diabetes. Daily use of an EO mouthrinse after ultrasonic debridement benefited patients with and without diabetes. 相似文献
32.
Alcohol Consumption and Periodontitis: Quantification of Periodontal Pathogens and Cytokines 下载免费PDF全文
Eugênio J.P. Lages Fernando O. Costa Sheila C. Cortelli José R. Cortelli Luís O.M. Cota Renata Magalhães Cyrino Elizabeth M.B. Lages Gilson C. Nobre‐Franco João A.R. Brito Ricardo S. Gomez 《Journal of periodontology》2015,86(9):1058-1068
Background: There are few studies on periodontal status related to microbiologic and immunologic profiles among individuals not or occasionally using alcohol and those with alcohol dependence. The aim of this study is to determine the effect of alcohol consumption on the levels of subgingival periodontal pathogens and proinflammatory cytokines (interleukin [IL]‐1β and tumor necrosis factor [TNF]‐α) in the gingival fluid among individuals with and without periodontitis. Methods: This observational analytic study includes 88 volunteers allocated in four groups (n = 22): individuals with alcohol dependence and periodontitis (ADP), individuals with alcohol dependence and without periodontitis (ADNP), individuals not or occasionally using alcohol with periodontitis (NAP), and individuals not or occasionally using alcohol without periodontitis (NANP). Levels of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, and Fusobacterium nucleatum were determined by real‐time polymerase chain reaction on the basis of the subgingival biofilm, and IL‐1β and TNF‐α were quantified by enzyme‐linked immunosorbent assay in gingival fluid samples. Results: Individuals with alcohol dependence showed worse periodontal status and higher levels of P. intermedia, E. corrodens, F. nucleatum, and IL‐1β than non‐users. No significant correlations between TNF‐α and bacterial levels were observed. However, in the ADP group, higher levels of E. corrodens were correlated with higher levels of IL‐1β. Conclusion: A negative influence of alcohol consumption was observed on clinical and microbiologic periodontal parameters, as well as a slight influence on immunologic parameters, signaling the need for additional studies. 相似文献
33.
Exenatide and Sitagliptin Decrease Interleukin 1β, Matrix Metalloproteinase 9, and Nitric Oxide Synthase 2 Gene Expression But Does Not Reduce Alveolar Bone Loss in Rats With Periodontitis 下载免费PDF全文
Renata M. Moraes Gabriela M. G. Lima Felipe E. Oliveira Ana Carolina V. Brito Rodrigo C. Pereira Luciane D. Oliveira Patrícia P. Barros Gilson C. N. Franco Ana Lia Anbinder 《Journal of periodontology》2015,86(11):1287-1295
Background: New drugs for the treatment of diabetes, glucagon‐like peptide‐1 (GLP‐1) receptor agonists and inhibitors of dipeptidyl peptidase‐4 (DPP‐4) have shown pleiotropic effects on bone metabolism and anti‐inflammatory properties. The aim of this study is to evaluate the effects of exenatide (GLP‐1 agonist) and sitagliptin (DPP‐4 inhibitor) during periodontitis induction by ligature insertion in rats. Methods: Forty rats were divided into four groups: 1) animals with induced periodontitis that received exenatide (EG); 2) animals with induced periodontitis that received sitagliptin (SG); 3) animals with induced periodontitis and without drug treatment (LG); and 4) animals without induced periodontitis and without drug treatment (controls). The drugs were administered for 28 days. On the day the animals were sacrificed, blood was collected for analysis of glucose and DPP‐4 levels. The gene expressions of prostaglandin‐endoperoxide synthase 2, tissue inhibitor of metalloproteinase 1, Dpp4, nitric oxide synthase 2 (Nos2), interleukin 1β (Il1b), and matrix metalloproteinase 9 (Mmp9) in the gingiva; support and alveolar bone loss; connective tissue attachment; and the quantity of gingival collagen were evaluated. Results: Exenatide and sitagliptin treatments have led to a lower percentage of weight gain but did not influence glycemia. Sitagliptin reduced the serum concentration of DPP‐4. Interestingly, although the gene expression profile has revealed a downregulation of Mmp9, Nos2, and Il1b in both EG and SG compared to LG, a significant protective effect was not observed on alveolar bone and collagen tissue in this model. Conclusion: Regardless of the reduction of the expression of Il1b, Nos2, and Mmp9, the drugs were not effective in the stabilization or reduction of alveolar bone loss and collagen degradation in rats. 相似文献
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35.
Assessment of aldehyde dehydrogenase in viable cells 总被引:3,自引:4,他引:3
Jones RJ; Barber JP; Vala MS; Collector MI; Kaufmann SH; Ludeman SM; Colvin OM; Hilton J 《Blood》1995,85(10):2742-2746
Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations. 相似文献
36.
37.
Anal cancer is one of the most common non‐AIDS‐defining malignancies in the era of combination antiretroviral therapy. Its precursor lesion, anal intraepithelial neoplasia (AIN), is highly prevalent in HIV‐infected populations. More than 90% of anal squamous cell cancers are attributable to human papillomavirus (HPV). While the biology of HPV‐related intraepithelial neoplasia is consistent across lower anogenital sites, the natural history of AIN is not well established and cannot be assumed to be identical to that of cervical intraepithelial neoplasia. Screening strategies to prevent anal cancer should be developed based on robust natural history data in HIV‐infected and uninfected populations. Likewise, treatments need to be tested in randomized clinical trials, and reserved for those at significant risk of progression to cancer. This review covers the epidemiology, pathogenesis and immunology of HPV infection, AIN and anal cancer, and summarizes the current diagnosis, screening and treatment strategies in HIV‐infected adults. 相似文献
38.
39.
Alexandre L. Pereira Gilson C. Franco Sheila C. Cortelli Davi R. Aquino Fernando O. Costa Suzane A. Raslan José R. Cortelli 《Journal of periodontology》2013,84(10):1445-1453
Background: Expression patterns of human β‐defensin‐2 (HBD‐2) mRNA or HBD‐2 protein concentration and periodontal diseases have been a focus of scientific research. This study compares the salivary levels of HBD‐2 protein concentration of healthy patients and patients with gingivitis and chronic periodontitis (CP) and correlates these levels with the presence of periodontopathogens. Methods: A total of 89 patients were enrolled in this study: 31 periodontally healthy, 27 with gingivitis, and 31 with CP. Plaque and gingival indices, probing depth, and clinical attachment level were measured. The presence of Campylobacter rectus, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Prevotella intermedia was evaluated qualitatively by conventional polymerase chain reaction. HBD‐2 quantification in saliva was performed using an immune enzymatic assay. Frequency of periodontopathogens and HBD‐2 protein concentration was assessed. Association between HBD‐2 protein concentration (≥100 pg/mL) and the simultaneous presence of one to two, three to four, or five to six periodontopathogens was tested. Results: Although periodontally healthy individuals and patients with gingivitis showed similar HBD‐2 levels, the CP group displayed an increased level of HBD‐2. P. gingivalis, P. intermedia, T. forsythia, and T. denticola were more prevalent in CP; however, their mere presence was not related to the increased levels of HBD‐2 (Pearson correlation and multinomial logistic regression model). Conclusions: Salivary HBD‐2 protein concentration was higher in patients with CP compared with healthy individuals or patients with gingivitis. These different protein concentrations were not related to the frequency of periodontopathogens. Clinical inflammatory profile had a higher impact on salivary HBD‐2 levels than bacteria. 相似文献
40.