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31.
In the present study, the effects of magnesium sulfate on tissue lactate and malondialdehyde (MDA) levels after cerebral ischemia in rabbits were studied. The rabbits were divided equally into three groups. Group 1 (n = 8) was the sham-operated control group, in group 2 (n = 8) only cerebral ischemia was induced by clamping bilaterally the common carotid arteries for 60 min, and in group 3 (n = 8) magnesium sulfate was administered at a dose of 100 mg/kg i.v. within 5 min after opening the clamps. In group 1 EEG recordings were obtained immediately and 60 and 120 min after craniectomy. In groups 2 and 3 EEG recordings were obtained immediately after craniectomy but before clamping and 60 min after clamping. One hour after opening the clamps and taking EEG recordings, brain cortices were resected, and the concentrations of lactate and MDA were determined using spectrophotometric/enzymatic and thiobarbituric acid methods, respectively. In all groups, there were significant differences between MDA and lactate levels (p < 0.05). There were no significant differences in lactate levels between groups 2 and 3 (p > 0.05), and also the preischemic EEG grades were the same in all groups. Preischemic and postischemic EEG values were significantly different (p < 0.05), and there were also significant differences between postischemic EEG grades in groups 2 and 3 (p < 0.05). There was a correlation between postischemic EEG grades and MDA and lactate levels. These results demonstrate that cerebral ischemia-reperfusion injury leads to an increase in brain tissue lactate and MDA levels, that magnesium sulfate suppresses the increase of MDA and lactate concentrations, and that magnesium sulfate treatment improves the EEG changes. The EEG grades correlated well with MDA and lactate levels.  相似文献   
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Objective: Nocturnal enuresis and constipation are common pediatric problems. The aim of this study was to assess the incidence of constipation in children with or without monosymptomatic primary nocturnal enuresis.Methods: The study included 5350 children, ages 5–19 years, who were surveyed to detect the incidence of nocturnal enuresis. Of those surveyed, 679 (12.7%) had primary nocturnal enuresis. All children were questioned by mail with a standard form that addressed their micturition and defecation habits. The children those who had primary nocturnal enuresis were invited to the Pediatric Urology Section of the University Hospital. Of those 679 children, 125 kept that invitation. All 125 of those children underwent an abdominal ultrasound. Also, these children had serum creatinine levels drawn and plain abdominal films taken.Results: Constipation, defined as less than 3 bowel movements per week, was seen in 48 of 679 children with nocturnal enuresis (7.06%). Of those 4671 children without nocturnal enuresis, only 68 (1.45%) had constipation. The difference in constipation between the two groups was statistically significant (z = –9.251; p = 0.000). Of note, 10 of the 125 children (8%), evaluated at the hospital, had constipation. None of the children had an abnormal neurologic examination. Finally, faecal loading was detected on the plain films of 8 of the 125 children evaluated, 7 of who had constipation. The sensitivity of grading plain films for faecal loading to denote constipation in this population was 87.5%.Conclusions: Children with primary nocturnal enuresis should be thoroughly assessed for coexisting constipation.  相似文献   
34.
In the present study the toxic effects of ropivacaine and bupivacaine on the cardiovascular and respiratory systems of rabbits were studied. Both drugs were administered intravenously at doses of 0.5, 1, 2.5, 5 and 10 mumol/kg. The effects of the two drugs on blood pressure, ECG and respiration rate were evaluated by considering the changes occurring 30 sec after intravenous bolus injection. High doses (5 and 10 mumol/kg) of bupivacaine and ropivacaine significantly reduced the heart rate and systolic pressure (p < 0.05). Five and 10 mumol/kg of bupivacaine significantly reduced diastolic pressure (p < 0.05), but only the 10 mumol/kg dose of ropivacaine had the same effect. Low doses of bupivacaine and high doses of ropivacaine significantly increased the PR interval, QRS duration and QT interval (p < 0.05). The 5 mumol/kg dose of bupivacaine caused ventricular tachycardia in 3 of 6 rabbits, whereas ropivacaine caused tachycardia in 1 of 5 rabbits. Neither drug had a significant effect on respiration rate or blood gas values (p > 0.05). The results indicate that ropivacaine is less cardiodepressive and arrhythmogenic than bupivacaine.  相似文献   
35.
The bilateral V-Y advancement flaps are used commonly in the closure of circular skin defects. We modified the standard bilateral V-Y advancement flap technique to reduce the tension along the closure, and used it in 10 patients between 1995 and 1997. In the presence of a circular defect, bilateral V-Y advancement flaps were marked on the skin, with the height of the V flaps measuring 1.5 to 2 times the diameter of the defect. The limbs of the V were not drawn as straight lines, but were curved outward slightly, making the flap and its two extensions broader than the standard V-Y flap. The broad extensions of the V flaps encircled the defect from above and below. Skin incisions were made vertically down to the muscle fascia. Additional undermining was carried out to elevate the upper and lower extensions of the V flaps for a distance that equaled the radius of the defect. The upper and lower extensions of the V flap on one side were transposed into the defect and sutured to the concave base of the opposing flap V flap at its midpoint. These extensions were then sutured to each other. The extensions of the opposing V flap were then transposed into the defect; the upper being superior and the lower being inferior to the extensions of the first flap. The rest of the operation was completed by advancement of the V flaps and closure in a Y configuration. The efficient redistribution of available tissue by the combined use of transposition and advancement principles resulted in the repair of relatively large skin defects with reduced tension along the closure. Satisfactory results were obtained in all patients in this series without any surgical complication.  相似文献   
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37.
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   
38.
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   
39.
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   
40.
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   
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