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101.
The herpesvirus-Porphyromonas gingivalis-periodontitis axis   总被引:3,自引:0,他引:3  
OBJECTIVES AND BACKGROUND: Members of the herpesvirus family have accumulated considerable support for a role in severe types of periodontitis. This study aimed to examine whether human cytomegalovirus (HCMV), Epstein-Barr virus type 1 (EBV-1) or herpes simplex virus (HSV) together with the major periodontopathic bacterium Porphyromonas gingivalis might interact in the pathogenesis of periodontal breakdown. METHODS: Sixteen subjects each contributed paper point samples from two progressing and two stable periodontitis lesions, as determined by ongoing loss of probing attachment. Polymerase chain reaction methodology was used to identify subgingival herpesviruses, P. gingivalis and other bacterial pathogens. Chi-squared tests and multivariate logistic regression were employed to identify statistical associations between herpesviruses, periodontopathic bacteria and clinical variables. RESULTS: HCMV and HSV were both significant predictors of the presence of subgingival P. gingivalis. In turn, P. gingivalis was positively associated with periodontitis active disease, probing attachment level, probing pocket depth, gingival bleeding upon probing and patient age. EBV-1 was not linked to P. gingivalis, although the virus was predictive of periodontitis active disease. The periodontitis disease risk associated with herpesvirus-P. gingivalis combinations depended on both site-specific and subject-specific factors. CONCLUSION: The present data of aggressive periodontitis implicate HCMV, HSV and P. gingivalis as either cofactors in its etiology or triggers of relapses. Further studies are needed to determine the spectrum of periodontopathogenicity of herpesviruses and effective management of these viruses in periodontal sites.  相似文献   
102.
Herpesviruses in periapical pathosis: an etiopathogenic relationship?   总被引:3,自引:0,他引:3  
BACKGROUND: Much remains to be learned about the etiopathogenesis of periapical pathosis, especially about the molecular events preceding and causing disease onset. Human cytomegalovirus and Epstein-Barr virus, 2 herpesviruses, are discussed in this review as they relate to apical periodontitis in humans. RESULTS: Cytomegalovirus or Epstein-Barr virus active infections are detected in more than 90% of granulomas of symptomatic and large periapical lesions. Dual infection with cytomegalovirus and Epstein-Barr virus is closely associated with symptomatic lesions. Herpes simplex virus active infection has no apparent relationship to periapical disease. DISCUSSION: The available evidence suggests the involvement of active cytomegalovirus and Epstein-Barr infections in the etiopathogenesis of apical periodontitis. In periapical pathosis, herpesviruses may cause the release of tissue-destructive cytokines, the overgrowth of pathogenic bacteria, and the initiation of cytotoxic or immunopathologic events. Immune impairment resulting from herpesvirus infection may aid bacteria at several stages of the pathogenesis of periapical lesions, including growth in the periapical environment, possible invasion of tissue, and direct damage to tissue. Unraveling the etiology and pathogenesis of periapical pathosis may require a broadening of our experimental approaches to include studies on interactions among herpesviruses, bacteria, and host immune reactions. Understanding the significance of herpesviruses in the development of periapical lesions may aid in the diagnosis, prevention, and treatment of the diseases.  相似文献   
103.
BACKGROUND: Although herpesviruses have been associated with adult periodontitis, their relationship with juvenile periodontitis (JP) has not been established. This case-control study examined possible associations between JP and pathogenic bacteria, the human cytomegalovirus (HCMV), and the Epstein-Barr type 1 virus (EBV-1). METHODS: Subjects were participants in a larger survey of schoolchildren in North-Central Jamaica. Subgingival plaque samples from 15 subjects with JP, 20 with incipient periodontitis (IP), and 65 randomly-selected healthy controls were assayed for Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans using a 16S rRNA polymerase chain reaction (PCR) identification method, and for HCMV and EBV-1 using nested PCR identification. RESULTS: Strong bivariate associations were found between JP and P. gingivalis (odds ratio [OR] = 12.7; 95% CI = 2.6, 61.4), HCMV (OR = 10.0; 95% CI = 2.7, 36.3), and A. actinomycetemcomitans (OR = 8.0; 95% CI = 2.3, 27.5), but not EBV-1. In multivariate analyses, P. gingivalis remained a significant explanatory variable (OR = 7.8; 95% CI = 1.5, 40.9); however, the associations were marginal for HCMV (OR = 4.6; 95% CI = 0.9, 22.7), and non-significant for A. actinomycetemcomitans (OR = 2.0; 95% CI = 0.4, 9.7). The associations with JP and the extent of attachment loss were even stronger when both P. gingivalis and HCMV were detected together. P. gingivalis (OR = 3.9; 95% CI = 1.3, 12.0) and EBV-1 (OR = 3.3; 95% CI = 1.0, 10.3) were the only significant explanatory variables in the multivariate analysis of IP. CONCLUSIONS: P. gingivalis is the strongest and most stable indicator of periodontitis in Jamaican adolescents. Co-infection with P. gingivalis and HCMV appears to be particularly deleterious to periodontal health.  相似文献   
104.
BACKGROUND: The present study determined risk indicators for oral colonization by Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, and Treponema denticola in 150 children and adolescents, 4 to 16 years of age, living in Los Angeles, California. METHODS: Fifty Caucasians, 50 Hispanics, and 50 Asian-Americans completed a questionnaire on demographic characteristics. 16S rRNA-based polymerase chain reaction identification was employed to determine the presence of test bacteria in unstimulated saliva. Step-wise logistic regression analysis identified explanatory variables (risk indicators) accounting for the salivary presence of periodontopathic bacteria. RESULTS: A. actinomycetemcomitans occurred in 15%, P. gingivalis in 15%, B. forsythus in 14%, and T. denticola in 18% of all subjects. Two or more pathogens were detected in 20% of Hispanic subjects and in 12% of Asian-American subjects but not in any Caucasians (P = 0.0005, chi square test). However, no stable multivariate model including ethnicity was found for multiple pathogens. Risk for harboring any pathogens increased with the length of time lapse from last dental visit (odds ratio [OR], 4.46; 95% confidence interval [CI], 1.83 to 12.21), and decreased with higher education level of the mother (OR, 0.258; 95% CI, 0.052 to 0.875). Risk for harboring 2 or more periodontal pathogens decreased with the years the parents had resided in the United States (OR, 0.95; 95% CI, 0.901 to 0.992). Risk for harboring A. actinomycetemcomitans decreased as the number of years the parents had resided in the United States increased (OR, 0.91; 95% CI, 0.86 to 0.95), and decreased with higher income level of the father (OR, 0.201; 95% CI, 0.038 to 0.948). Girls were at higher risk for harboring P. gingivalis (OR, 2.55; 95% CI, 1.02 to 7.03), but at lower risk for carrying T. denticola (OR, 0.42; 95% CI, 0.17 to 0.98). CONCLUSIONS: This study showed that salivary occurrence of periodontopathic bacteria in young individuals was related to the length of time the parents had lived in the United States, education level of the mother, length of time since last dental visit, and gender, but apparently not to ethnicity per se.  相似文献   
105.
BACKGROUND: The goal of follow-up care after periodontal therapy is to preserve the function of individual teeth and the dentition, ameliorate symptoms and simplify future surgery or make it unnecessary. Effective follow-up periodontal care depends on early diagnosis and treatment, as well as patient education. RESULTS: The main determinants of successful periodontal maintenance therapy are dental professionals' ability to combat periodontal infections and patients' compliance with prescribed follow-up care. Mechanical and chemical antimicrobial intervention is the mainstay of preventive periodontal therapy. Chemotherapeutics alone are unlikely to be effective in the presence of subgingival calculus, underscoring the importance of subgingival mechanical débridement. Also, because toothbrushing and rinsing alone do not reach pathogens residing in periodontal pockets of increased depths, oral hygiene procedures should include subgingival treatment with home irrigators or other appropriate self-care remedies. CLINICAL IMPLICATIONS: When considering possible preventive therapies, dental professionals must weigh the risk of patients' acquiring destructive periodontal disease against potentially adverse effects, financial costs and inconvenience of the preventive treatment. The authors discuss theoretical and practical aspects of follow-up care for patients with periodontal disease. In addition, because it can be both difficult and expensive to control periodontal disease via conventional preventive measures alone, they present a new, simple and more cost-effective antimicrobial protocol for supportive periodontal therapy.  相似文献   
106.
BACKGROUND: Genomic sequences of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV), two herpesviruses, can frequently be detected in periodontal pockets of progressive periodontitis lesions, but the prevalence and load of the two viruses in gingival tissue are unknown. This study determined levels of HCMV and EBV DNA in the periodontal pocket and in the adjacent gingiva of periodontitis lesions using a real-time polymerase chain reaction (PCR) assay. MATERIAL AND METHODS: A total of 20 systemically healthy periodontitis patients participated in the study. Nine patients below 35 years of age were tentatively diagnosed as having aggressive (early onset) periodontitis, and 11 patients 36-56 years of age as having chronic (adult) periodontitis. Clinical parameters were evaluated using established methods. Using periodontal curettes, specimens were harvested from 6-10 mm periodontal pockets and from the adjacent inflamed periodontal pocket wall. A 5'-nuclease (TaqMan) real-time PCR assay was used to identify and quantify genomic copies of periodontal HCMV and EBV. RESULTS: HCMV DNA was detected in 78% of subgingival and 33% of gingival tissue samples from aggressive periodontitis lesions, but only in 46% of subgingival and 9% of gingival tissue samples from chronic periodontitis lesions. In aggressive periodontitis, HCMV subgingival and gingival tissue counts were positively correlated with periodontal pocket depth and probing attachment loss at sample sites (p6 mm, but none of 14 patients having mean pocket depth at sample teeth相似文献   
107.
Abstract 22 females and 3 males with primary hypogammaglobulinaemia (n=6) or IgG subclass deficiencies with (n=3) or without (n=16) concomitant IgA deficiency were examined for periodontal disease and dental caries. Only 1 patient showed more tooth loss than that found in the normal Swedish population. 1 patient demonstrated advanced periodontal disease. No patient exhibited more severe dental caries than that of comparable normal Swedes. Microbiological samples from periodontal pockets and saliva showed recovery of potential periodontopathic and cariogenic bacteria within normal ranges. This study could not support the notion that immunodeficient subjects exhibit an increased risk of developing periodontal disease or dental caries.  相似文献   
108.
Genetic analysis of Porphyromonas gingivalis strains may distinguish between virulent and nonvirulent strains and also may be used to trace individual strains in epidemiological studies. The present study examined the utility of the arbitrarily primed polymerase chain reaction for genotypic fingerprinting of P. gingivalis. DNA was extracted according to conventional methods. Ten-base oligonucleotide primers with arbitrary sequences were used with the polymerase chain reaction to amplify P. gingivalis genomic DNA. The amplification products were analyzed by agarose gel electrophoresis. The primer GACCGCTTGT grouped 73 P. gingivalis strains into 23 genotypes, including 16 genotypes containing a single strain each. The primer AGGGGTCTTG identified 45 different genotypes, 33 of which contained a single strain. P. gingivalis strains ATCC 332771T and 381 belonged to the same genotype. Likewise, strains W50 and W83 were of the same genetic clone. The present study indicates that the arbitarily primed polymerase chain reaction represents a valuable and easy method for clonal analysis of P. gingivalis.  相似文献   
109.
Intraosseous, periodontal defects in 12 subjects initially treated by root planing alone (21 defects) or by flap surgery (21 defects) were monitored during a 5-year postoperative interval. Maintenance therapy during this interval was limited to reinforcement of oral hygiene and tooth polishing every 6 months. No subgingival instrumentation was performed at the defect sites. Longitudinal clinical measurements demonstrated that surgically-treated lesions responded with somewhat more reduction of probing depth and more gain of probing bone level than root-planed lesions. Mean gains of probing attachment level were similar for the 2 treatments. Some relapse of the clinical conditions could be observed towards the end of the 5-year observation interval compared to the results at year 1 and year 2. However, the majority of defects subjected to either treatment showed 60-month recordings of probing attachment and probing bone levels equal to or slightly improved compared to those at baseline. Counts from cultures of subgingival, microbial samples were obtained at 42, 48 and 60 months. No significant difference between the 2 therapies was observed for the investigated groups of micro-organisms.  相似文献   
110.
In a previous study, we observed that root debridement was inefficient in eliminating Actinobacillus actinomycetemcomitans from adult periodontitis lesions. The present report describes the effects on A. actinomycetemcomitans of subsequent treatments of 6 patients that had at least 2 separate sites still harboring A. actinomycetemcomitans 6 months following debridement. 1 site or more in each individual was treated with renewed root debridement and at least 1 other site was treated by surgical excision of the gingival tissue. The results indicated that retreatment with either repeated root debridement or with surgical excision of the gingival tissue was not more effective in eliminating A. actinomycetemcomitans than initial debridement. The possible reasons for this limited therapeutic effect on the subgingival presence of A. actinomycetemcomitans are discussed.  相似文献   
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