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71.
Objective: To evaluate the efficacy of 16% carbamide peroxide gel (CP16%), tetrahydrate sodium perborate (SP) and mixture (CP16% + SP), in walking bleaching of non-vital discolored teeth. Materials and methods: Sixty single-rooted human premolars with intact crowns were used and initial color was assessed using Vita shade guide and standardized photos. The teeth were stained using rabbit fresh blood for 18 days and photos of discolored teeth and color evaluation were performed. The teeth were divided into 4 groups (n = 15), according to bleaching agent used: G1) CP16% gel; G2) CP16% gel + SP; G3) SP + distilled water; G4: control. The bleaching agents were replaced twice at 7-day intervals for 21 days. All teeth were evaluated by two endodontists at days 0, 7, 14 and 21 and the color changes were assessed using Vita shade guide and standardized photos. The results were analyzed by Kruskal-Wallis and Dunn''s tests (p=0.05). Results: The experimental groups presented statistically similar bleaching results (p>0.05) at the end of 7, 14 and 21 days. These groups presented significantly higher bleaching efficacy than control group (G4) (p<0.05). The mixture CP16% + SP promoted return of original color in 100% of teeth at the end of 21 days. Conclusion: It was concluded that three bleaching agents were effective in bleaching of stained teeth with blood products, especially at the end of 21 days.  相似文献   
72.

Background

Attention to additional factors affecting the success of assisted reproduction techniques (ARTs) is very important and with appropriate interventions in some of these factors, success rate can be as high as improve a lot. There is a lot of evidence that lifestyle factors can influence on ARTs outcomes. Current knowledge of the effect of combined effect of several lifestyle factors on the outcomes of ARTs is low and contradictory. The importance of the causality of this phenomenon is felt by the pandemic of inappropriate lifestyle as well as the dramatic increase in infertility in the world. The aim of this cohort study is to scrutinize the casual effect of a specific range of contemporary lifestyle factors on ARTs outcomes.

Methods

A prospective cohort study will be conducted in Royan institute, Tehran, Iran. Each infertile couple will be monitored from the first visit to the end of treatment cycle. The data will be collected electronically and include the following: detailed interview about lifestyle and socioeconomic status, past medical history, general physical examination, assessment of menstrual and ovulatory status, assessment of tuboperitoneal, assessment of uterine, assessment of cervix, urogenital examination, semen analysis, anti-sperm antibodies, biochemical analysis, sperm-cervical mucus contact test, in vitro cervical mucus penetration test and sperm functional assays. To estimate the casual effect of lifestyle variables on clinical pregnancy and live birth, the obtained propensity score (PS) from generalized boosted models (GBM) will be matched between couple with and without live birth.

Discussion

This is the first study to prospectively obtain detailed information on causes of ARTs success. Determining the casual effect of lifestyle variables on ARTs success will be important to inform strategies most likely to increase the success rates in ARTs.
  相似文献   
73.
74.
Insectivorous bats are the main reservoirs of rabies virus (RABV) in various regions of the world. The aims of this study were to (a) establish genealogies for RABV strains from different species of Brazilian insectivorous bats based on the nucleoprotein (N) and glycoprotein (G) genes, (b) investigate specific RABV lineages associated with certain genera of bats and (c) identify molecular markers that can distinguish between these lineages. The genealogic analysis of N and G from 57 RABV strains revealed seven genus-specific clusters related to the insectivorous bats Myotis, Eptesicus, Nyctinomops, Molossus, Tadarida, Histiotus and Lasiurus. Molecular markers in the amino acid sequences were identified which were specific to the seven clusters. These results, which constitute a novel finding for this pathogen, show that there are at least seven independent epidemiological rabies cycles maintained by seven genera of insectivorous bats in Brazil.  相似文献   
75.
76.

Object

To compare between results of bacterial cellulose graft myringoplasty and fat graft myingoplasty in patients had mild or moderate size safe perforation.

Methods

120 patients undergoing myringoplasty due to mild or moderate size perforation were divided into 3 groups: group I: 40 patients undergoing myringoplasty with use of bacterial cellulose graft, group II: 40 patients undergoing myringoplasty with use of fat graft, group III: 40 patients undergoing usual myringoplasty with use of temporalis fascia graft (control group).

Results

Healing in 20 patients with small perforation and 17 patients with moderate perforation in Group I, Healing in 15 patients with small perforation and 10 patients with moderate perforation in Group II, Healing in 18 patients with small perforation and 12 patients with moderate perforation in Group III.

Conclusion

Bacterial cellulose graft myringoplasty would be a good, simple, rapid and safe surgery that could be done under local anesthesia in outpatient clinic with shorter time of surgery than fat graft myringoplasty and temporalis fascia graft myringoplasty, with better hearing and healing.

Summary at glance

120 patients undergoing myringoplasty were divided into 3 groups to compare between results of bacterial cellulose graft myringoplasty, fat graft myringoplasty and temporalis fascia graft myringoplasty.  相似文献   
77.
Outbreaks of hepatitis A may occur in countries of medium and high socioeconomic levels in which the population generally exhibits an increased susceptibility in young adults to this infection if they are not vaccinated against the hepatitis A virus (HAV). In Europe, an outbreak involved approximately 22 European countries with 4475 cases reported from 2016 to 2018; most of them were men who have sex with men (MSM). This outbreak expanded to North and South America, including Brazil, particularly in São Paulo city with 1547 reported cases from 2016 to 2019. In the present study, we characterized the HAV strains involved in the acute hepatitis A cases identified in the reference centers of São Paulo city during this outbreak. A total of 51 cases with positive anti-HAV IgM were included, 80.4% male, 68.6% of them between 20 and 40 years old and 41.7% MSM. HAV RNA was detected in 92% (47/51) of the cases. Subgenotype IA of HAV was identified and most of the strains were closely related to that isolated in outbreaks that occurred in different European countries in 2016. These results showed the epidemiological relation between these outbreaks and reinforce the need to implement vaccination against hepatitis A for the adult population, particularly for a population with a high-risk behavior.  相似文献   
78.
79.
The Revised Fibromyalgia Impact Questionnaire (FIQ-R) is an updated version of the FIQ attempts to address the limitations of the Fibromyalgia Impact Questionnaire (FIQ). As there is no Moroccan version of the FIQ-R available, we aimed to investigate the validity and reliability of a Moroccan translation of the FIQR in Moroccan fibromyalgia (FM) patients. After translating the FIQR into Moroccan, it was administered to 80 patients with FM. All of the patients filled out the questionnaire together with Arabic version of short form-36 (SF-36). The tender-point count was calculated from tender points identified by thumb palpation. Three days later, FM patients filled out the Moroccan FIQR at their second visit. The test–retest reliability of the Moroccan FIQR questions ranged from 0.72 to 0.87. The test and retest reliability of total FIQR score was 0.84. Cronbach’s alpha was 0.91 for FIQR visit 1 (the first assessment) and 0.92 for FIQR visit 2 (the second assessment), indicating acceptable levels of internal consistency for both assessments. Significant correlations for construct validity were obtained between the Moroccan FIQ-R total and domain scores and the subscales of the SF-36 (FIQR total versus SF-36 physical component score and mental component score were r = ?0.69, P < 0.01 and r = ?0.56, P < 0.01, respectively). The Moroccan FIQ-R showed adequate reliability and validity. This instrument can be used in the clinical evaluation of Moroccan and Arabic-speaking patients with FM.  相似文献   
80.
The objectives of this study are to translate, adapt in the Moroccan cultural context, and validate in patients with ankylosing spondylitis (AS) the Bath Ankylosing Spondylitis Functional Index (BASFI) and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). The cross-cultural adaptation of the BASFI and BASDAI was obtained in accordance with the guidelines for translation of the health status measures. Eighty-five patients with AS were included in the study. The test–retest reliability and the internal consistency were analyzed, and both questionnaires were assessed for external construct validity. Structural validity was analyzed with correlation matrix. Twenty-four-hour test–retest reliability was good: BASFI intraclass correlation coefficient (ICC) = 0.96 (confidence interval (CI) at 95%, 0.93–0.97), BASDAI ICC = 0.93 (CI at 95%, 0.90–0.95). Cronbach’s alpha was 0.90 for the BASFI and 0.86 for BASDAI. The construct validity of the instruments was evaluated. The BASFI showed a strong validity when correlating its results with Schober’s test (r = −0.56), occipital wall distance (r = 0.46), chest expansion (r = −0.46), BASDAI (r = 0.54), Bath Ankylosing Spondylitis Metrology Index (r = 0.70), Bath Ankylosing Spondylitis Global Score (BAS-G; r = 0.58), Bath Ankylosing Spondylitis Radiology Index (r = 0.61), and the radiological changes in sacroiliac joints (r = 0.54). A good correlation was observed between the BASDAI and the spinal pain (r = 0.53), the number of nocturnal awakenings (r = 0.57), the morning stiffness (r = 0.65), the enthesic index (r = 0.47), the BAS-G (r = 0.53), the BASFI (r = 0.54), and the erythrocyte sedimentation rate (r = 0.41; for all p < 0.001). The correlation matrix showed an intermediate correlation between items. The Moroccan version of the BASFI and the BASDAI showed adequate reliability and validity. These instruments can be used in the clinical evaluation of Moroccan and Arabic-speaking patients with AS.  相似文献   
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