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71.
Aim  To compare the fracture resistance of thin-walled roots after restoration with different types of post systems.
Methodology  One hundred and sixty-five decoronated maxillary central incisors were root filled and randomly assigned to three groups with respect to the remaining dentine thickness of root (1.0 mm, 1.5 mm, 2.0 mm). Each group was randomly divided into five equal subgroups. The subgroups were restored with one of the following post systems: polyethylene woven fibre (R), composite resin cured by light-transmitting post + glass fibre post (L), electrical glass fibre post (E), composite corono-radicular restoration (C) and cast metal post (M). Standard cores were constructed using composite resin in the first four groups. The samples were subjected to a gradually increasing force (1 mm min−1). The force required to fracture was recorded. The data was analysed with anova and Tukey test ( P  = 0.05).
Results  The cast metal post group had the highest fracture strength ( P  < 0.001). There was no significant difference in fracture resistance between the other four groups. Fracture resistance was affected largely by the remaining dentine thickness in fibre post groups; however, the difference was not significant. On the contrary in the cast metal post group load failure was inversely influenced by axio-proximal dimension of dentine walls.
Conclusion  The cast post group had a higher fracture strength than resin groups. The force required to fracture the roots was similar for all fibre post systems and for all dentine thicknesses.  相似文献   
72.
Wound infection after a surgical procedure is one of the main problems affecting the success of an operation. The prepuce is used in hypospadias surgery and in tissue defects in reconstructive surgery. The objective of this study is to determine the efficacy of povidone-iodine and surgical soap in preputial skin preparation. Ninety-four healthy children were divided into three groups. After obtaining preputial skin swabs, an application of povidone-iodine 10% was made and skin swabs were obtained after two and five minutes in group 1. An additional application of povidone-iodine after two minutes was made in group 2 and swabs taken. Group 3 received a local scrub with surgical soap and an application of povidone-iodine. Results showed that, despite painting with povidone-iodine and/or local cleaning with surgical soap, it is not possible totally to eradicate the micro-organisms in the prepuce. Surgical soap decreases the colony count, which can lead to increased effectiveness of povidone-iodine after painting. We recommend preoperative local cleaning with surgical soap before surgical painting.  相似文献   
73.
BACKGROUND: The transmission of viral infections via protein concentrates made from a large pool of plasma depends on the selection of donors, fractionation process, and virucidal methods. To date, no data are available on the infectivity risk of plasma concentrates of the inhibitor of the first component of complement (C1-INH). STUDY DESIGN AND METHODS: The prevalence of blood-borne viral infections and levels of transaminases were evaluated in patients treated with a large- pool plasma concentrate of the inhibitor of C1-INH before and after the introduction of virucidal methods. The study included 85 patients with hereditary angioedema and 4 with acquired angioedema. The patients were divided into three groups: 1) 48 untreated patients; 2) 22 patients treated with non-virus-inactivated C1-INH concentrates; and 3) 19 patients treated with virus-inactivated concentrates. Serum samples obtained at various times after the infusion of concentrate were assayed for alanine amino-transferase and tested for hepatitis B surface antigen and antibodies to hepatitis C virus (anti-HCV) and human immunodeficiency virus (anti-HIV); anti-HCV-negative subjects exposed to the concentrate were also tested for HCV RNA. RESULTS: Prevalences of HCV infection and elevated alanine aminotransferase are significantly lower in patients treated with virus-inactivated concentrates than in those exposed to non-virus-inactivated concentrates. No patients were anti-HIV positive. CONCLUSION: This study suggests that C1-INH concentrates transmitted HCV, but that the virucidal methods adopted are effective in reducing the infectivity.  相似文献   
74.
Transition to a new work area is often stressful for both experienced and new graduate nurses. It is essential that the new graduate be supported through this transition period to enable them to adjust to the environment itself, refine knowledge, and develop skills specific to their chosen clinical stream. In past years, several strategies have been designed with varying levels of success.This study evaluates an Australian transition support model, where the fundamental difference is that the management of the program is facilitated by a nurse possessing refined leadership, communication, clinical and organisational skills.The model has been evaluated on its effectiveness in meeting specific outcomes. The findings revealed that this coordinated team approach provided increased support for the new graduate, reduced the stress and workloads on the preceptors, whilst promoting confidence in the new starters and preventing conflict between preceptors and preceptees. The Coordinator’s role was shown to be an effective and crucial component in the Coordinated Team Preceptorship Model (CTPM) and findings illustrated that a team preceptorship model is not sustainable without a Coordinator.  相似文献   
75.
This multicentre, double-blind, randomized, placebo-controlled, parallel study was designed to evaluate the efficacy of combined oral lysine acetylsalicylate and metoclopramide (LAS-MCP) in the acute treatment of migraine attacks. A total of 266 patients, 18–65 years old, with two to six attacks of migraine with or without aura (IHS criteria) per month were included. The patients had to treat two migraine attacks with LAS-MCP (1620 mg lysine acetylsalicylate-the equivalent of 900 mg aspirin- combined with 10 mg metoclopramide) or placebo. The main outcome measure was headache relief (reduction in headache severity from grade 3 or 2-severe or moderate-to grade 1 or 0-mild or none) 2 h after treatment. LAS-MCP was superior to placebo for headache relief (56% vs 28%) and for the following secondary outcome measures: complete headache relief (18% vs 7%; p < 0.001), nausea (28% vs 44%; p < 0.001), vomiting (3% vs 11%; p = 0.001), use of rescue medication (47% vs 68%; p < 0.001), global efficacy judged as good or excellent (32% vs 14%; p < 0.001). The tolerability was considered as good in 94% of treated attacks in both groups. Combined oral lysine acetylsalicylate and metoclopramide is an effective and well-tolerated acute treatment of migraine attacks.  相似文献   
76.
BACKGROUND: Hepatitis G virus (HGV) is a blood-borne flavivirus that may cause acute and chronic transfusion-transmitted infections. Patients with complement component 1 (C1) inhibitor (C1-INH) deficiency may acquire blood-borne infections through infusion of plasma concentrates. STUDY DESIGN AND METHODS: Serum samples from 84 patients with C1-INH deficiency (19 who received unmodified C1-INH concentrates, 23 who received steam-heated concentrates, and 42 untreated patients) were tested for HGV RNA and hepatitis C virus (HCV) RNA by a nested polymerase chain reaction (PCR). The samples were also tested for antibodies to the E2 envelope protein of HGV (anti-HGV) and to HCV with enzyme-linked immunosorbent assays. RESULTS: Nine (11%) patients had serum HGV RNA; that is, 7 (17%) of 42 patients previously treated with C1-INH concentrates and 2 of 42 previously untreated patients. HGV RNA was as common in the 19 patients treated with unmodified concentrates as in the 23 given steam-heated concentrates (16 vs. 17%, p = 0.60). Anti-HGV was more common among the recipients of unmodified concentrates than among those given steam-heated concentrates (26 vs. 0%, p = 0.014). HCV RNA was more frequently detected in treated patients than in untreated patients (33 vs. 7%, p = 0.005) and in the 19 recipients of unmodified concentrates than in the 23 treated with steam-heated concentrates (58 vs. 16%, p = 0.003). Only one HGV RNA- seropositive patient had elevated serum aminotransferase activity, compared to 11 with HCV RNA. CONCLUSION: HGV was transmitted by both unmodified and steam-heated concentrates, but it caused persistent viremia in a minority of the cases and was rarely associated with liver disease.  相似文献   
77.
We aimed to investigate the association between drooling and possible etiological factors in Parkinson’s disease (PD) and to determine its effect on the quality of life. Demographic data of the 63 patients with idiopathic PD were recorded. Radboud Oral Motor Inventory for Parkinson’s disease (ROMP) test was administered to all patients to evaluate speech, swallowing functions, and saliva control. The freezing of gait questionnaire (FOGQ) was used to evaluate gait and freezing of gait. Dynamic Parkinson gait scale (DYPAGS) was administered for the objective quantification of PD gait features. Disease severity was assessed by UPDRS and modified Hoehn & Yahr Scale. PD specific health-related quality was evaluated by PDQ-39 questionnaire. Drooling was only significantly correlated to UPDRS score; a stronger association was found between drooling and UPDRS 3 motor score; and a more significant association was determined between drooling and the bradykinesia questions of the motor part of UPDRS 3. Interestingly, no significant association was found between sialorrhea score and PDQ-39 score. Based on the results of this study, we concluded that oropharyngeal bradykinesia may be responsible for drooling in PD. In contrast to a general expectation, we did not find any adverse impact of drooling on the quality of life.  相似文献   
78.
79.
The study aimed to determine the effects of cytostatic and genotoxic drugs used to treat breast cancer on sister chromatid exchange (SCE). SCE values were examined in 25 female patients with breast cancer in pre-treatment, treatment process and remission period as well as in 22 nonsmoker women via peripheral blood culture technique. The SCE values of patient and control group were analyzed via "Mann-Whitney U test". Whilst SCE values of patient group ??were 8.25 ± 3.67, 10.19 ± 2.95 and 11.52 ± 3.33 in pre-treatment, treatment process and remission periods respectively, it was 7.01 ± 1.24 in control group. When overall SCE values of patients group in pre-treatment period were compared with those of control group, no significant difference was observed (p > 0.05), whereas highly significant differences were observed between treatment process and remission period of patient groups and control group in terms of SCE values (p < 0.01). If patients are exposed to any cytostatic and clastogenic drugs, the increase in the exchange values was considered remarkable. These findings reinforced the availability of sister chromatid exchange technique in directing of treatment and monitoring the genetic abnormalities caused by genomic instability which may occur due to the drugs used for treatment.  相似文献   
80.
BACKGROUND AND AIM: Reactive oxygen radicals that cause remote organ injury are increased after the one-lung ventilation frequently used in thoracic surgery. The aim of this study was to examine the effects of one-lung ventilation on the liver and ileum. MATERIALS AND METHODS: Thirty rats were divided into five groups: a sham group; 3- and 4-h mechanical ventilation groups; and 1- and 2-h left lung collapse/2-h re-expansion groups (n = 6 for each group). In the collapse groups, the left lung was collapsed by bronchial occlusion for 1 and 2 h and then re-expanded and ventilated for an additional 2 h. At the end of the study, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were determined to assess liver functions. Myeloperoxidase (MPO) and malondialdehyde (MDA) activity were determined in the liver and ileum tissues. The tissues were also examined by light and electron microscope. Apoptosis was assessed using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) assay. RESULTS: Plasma ALT and AST, tissue MDA, and MPO activities in both tissues were significantly higher in the 2-h collapse/2-h re-expansion group than in the 4-h mechanical ventilation group (P < 0.05). Moreover, the levels were significantly higher in the 2-h collapse group compared to the 1-h collapse group (P < 0.016). Tissue damage and apoptotic index were most prominent in the 2-h collapse/2-h re-expansion group. CONCLUSION: Our findings showed that one-lung ventilation causes tissue damage in the liver and ileum and that this damage increases as occlusion duration rises.  相似文献   
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