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891.
Background: Although dental implants have a high success rate, failures occur, in spite of adequate clinical conditions. Together with the observation that multiple implant losses occur in certain groups of individuals (clusterization phenomenon), this suggests that host response may influence implant failure. Little is known about the influence of genetic susceptibility on implant loss. Interleukin (IL)-1β and IL-1ra are believed to play a key role in the immune-inflammatory response, and polymorphisms IL1B (C+3954T) and IL1RN (intron 2) are shown to alter the coding proteins expression.
Objectives: The aim of this study was to investigate the association between dental implant loss and polymorphisms IL1B (+3954) and IL1RN (intron 2).
Material and methods: The study population ( n =266) was divided into Test group (T) – 90 subjects with implant loss, and Control group (C) – 176 subjects without any implant failure. Genotyping was performed by PCR-RFLP.
Results: The number of present teeth was observed to influence implant loss. No differences in genotype and allele frequencies between C and T were found for IL1B (+3954) and IL1RN (intron 2) polymorphisms. However, the analysis of the whole study population (control and test groups) showed that genotype 2/2 was significantly more frequent in individuals with multiple implant losses ( n =35) than in individuals that lost up to a single implant ( n =231) (OR: 3.07, IC: 1.13–8.34, P =0.027).
Conclusion: It was observed that number of teeth and edentulism were associated with implant loss. Genotype 2/2 of IL1RN polymorphism was significantly more frequent in patients who presented multiple losses, which suggests that the clusterization phenomenon has a genetic basis.  相似文献   
892.
893.
Aims:  The current Royal College of Pathologists guidelines for pancreatoduodenectomy specimen reporting recommend that microscopic evidence of tumour within 1 mm of a resection margin (RM) should be classified as R1. No clinical evidence exists to justify this classification. The aim of this study was to identify the proportion of pancreatoduodenectomy specimens in which 'equivocal' RMs are present (tumour involvement within 1 mm of, but not directly reaching, one or more resection margins) and whether the survival of these patients was similar to that of patients with 'unequivocal' RM involvement.
Methods and results:  Patients with histologically confirmed pancreatic ductal adenocarcinoma undergoing pancreatoduodenectomy between 1997 and 2007 ( n  = 163) were identified from a prospective database. One hundred and twenty-eight cases (79%) were classified as R1. Of these, 57 (45% of all R1 cases) were based on 'equivocal' margin involvement. There was no significant difference in overall survival between equivocal and unequivocal R1 resections (log rank, P  = 0.102). All R1 resections had a poorer survival on univariate (log rank, P  = 0.013), but not multivariate, analysis (Cox, P  = 0.132).
Conclusions:  Our results indicate that cases with microscopic tumour involvement within 1 mm of a resection margin should be considered synonymous with incomplete excision for resected pancreatic cancer.  相似文献   
894.
895.
896.
The effects of fruiting body maturity on antioxidant activity and antioxidants production of the wild mushroom, Lactarius piperatus, were evaluated. Several biochemical assays were used to screen the antioxidant properties: reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, inhibition of erythrocytes hemolysis mediated by peroxyl radicals and inhibition of lipid peroxidation using the beta-carotene linoleate model system. The amounts of phenols, flavonoids, ascorbic acid, beta-carotene and lycopene present in the immature, mature and degraded fruiting bodies were also determined. The highest antioxidant contents and the lowest EC(50) values for antioxidant activity were obtained in the mature stage with immature spores.  相似文献   
897.
PURPOSE: The purpose of this study was to investigate the decision to obtain individualized risk assessment (IRA) after a breast cancer education session. METHODS: A sample of both African American and Caucasian women was used to determine if there were differences by race/ethnicity in uptake of the assessment and differences in the variables that were most predictive of uptake. The sample included 166 women between the ages of 18 and 80. Sixty-two percent of the sample were African American women. KEY FINDINGS: The results suggested that African American women and Caucasian women used different factors and used other factors differently to decide whether or not to obtain an IRA. CONCLUSIONS AND IMPLICATIONS: These results are discussed within the context of health disparities among ethnic minority and Caucasian women with implications for breast cancer control programs. The results of this study suggest that knowledge alone does not lead to opting for a personalized risk assessment, and that African American and Caucasian women use different pieces of information, or information differently to make decision about getting more personalized information about risk.  相似文献   
898.
In the present work we investigated the effects of Crotalus durissus terrificus venom (CdtV) on the pulmonary mechanic events [static and dynamic elastance, resistive (DeltaP1) and viscoelastic pressures (DeltaP2)] and histology after intramuscular injection of saline solution (control) or venom (0.6 microg/g). The static and dynamic elastance values were increased significantly after 3 h of venom inoculation, but were reduced at control values in the other periods studied. The DeltaP1 values that correspond to the resistive properties of lung tissue presented a significant increase after 6h of CdtV injection, reducing to basal levels 12h after the venom injection. In DeltaP2 analysis, correspondent to viscoelastic components, an increase occurred 12 h after the venom injection, returning to control values at 24 h. CdtV also caused an increase of leukocytes recruitment (3-24 h) to the airways wall as well as to the lung parenchyma. In conclusion, C. durissus terrificus rattlesnake venom leads to lung injury which is reverted, after 24 h of inoculation.  相似文献   
899.
BACKGROUND: This is an update of a 10-years student-staffed oncology clinic. METHODS: Students are divided into 4 teams; each sees 1 to 2 outpatients weekly. RESULTS: By April 2006, 95 medical students participated, 89% for 2 or more years; 70% reported activity contributed to ability to read medical papers, and 59% improved their scientific writing. Of 39 students currently involved, 33 (84%) improved clinical skills in taking history, 27 (69%) in physical examination, and 34 (87%) in physician-patient relation. A total of 21 (56%) reported increased knowledge in general internal medicine. Although only 11% of former students pursued a specialty in Medical Oncology, 77% rated this clinic as the best extracurricular activity. CONCLUSIONS: Attendance of outpatient clinic in medical oncology can contribute significantly to the general medical education.  相似文献   
900.
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