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21.
This study investigated the effect of rifampin on the thickness of capsules around silicone implants by bactericidal activity against Stapylococcus epidermidis. Silicone blocks (1 × 1 cm) were placed into pockets created for each of the 40 rats included in the study. In group 1, the operation was performed under aseptic conditions. In group 2, standard S. epidermidis was inoculated into the pocket, whereas rifampin and S. epidermidis were applied in group 3. In group 4, only rifampin was applied topically on implants. After 12 weeks, the peri-implant capsules were removed and examined under a photomicroscope and a scanning electron microscope. The mean thickness of the capsules was 63.307 μm in group 1, 111.538 μm in group 2, 43.076 μm in group 3, and 30.384 μm in group 4. The differences between groups 2 and 3 and groups 2 and 4 were found to be statistically significant (p < 0.001). Rifampin appears to be an agent for preventing peri-implant capsule formation.  相似文献   
22.
Auditory cortices are interconnected to each other by fibers passing through the corpus callosum (CC). In totally deaf persons no auditory impulses are conveyed to the auditory cortices, hence the auditory pathways become nonfunctional. It was reported that there has been cross-modal plasticity between auditory, visual, and somatosensory cortices. In this study, our aim was to make a comparison in the CC morphometry in hearing subjects and in a selected group in which the auditory system was deprived before the age of 2. 18 deaf and 18 hearing male, handedness matched volunteers, ages varying between 28 and 56 years old were examined. Audiometrical tests were applied to both groups and then T1-weighted midsagittal MR images were obtained. Certain dimensions and areas were measured on these images. There were no statistically significant difference between deaf and hearing subjects, either when dimensions and areas were analyzed by multivariate analysis of variance or when areas were analyzed by univariate analysis of variance. Absence of any significant morphometric difference in the CC of deaf subjects could be thought as an evidence of reflection of functional cortical plasticity.  相似文献   
23.
Neuropsychological tests target specific cognitive functions; however, numerous cognitive subcomponents are involved in each test. The aim of this study was to decompose the components of two frontal executive function tests, Go/NoGo (GNG) and cued continuous performance task (CPT), by analyzing event-related potentials (ERPs) of 24 subjects both in time and time-frequency domains. In the time domain, P1, N1, P2, N2 and P3 peak amplitudes and latencies and mean amplitudes of 100 ms time windows of the post-P3 time period were measured. For GNG, the N1 amplitude and for both GNG and CPT N2 amplitudes were significantly higher in the NoGo condition compared with the Go condition. P3 had a central maximum in the NoGo conditions of both paradigms in contrast to a parietal maximum in the Go conditions. All peaks except P1 and mean amplitudes of the post-P3 period were more positive in CPT compared to those of GNG. N1, N2 and P3 latencies were longer for the NoGo condition than the Go condition in the CPT. In time-frequency analyses, the NoGo condition evoked higher theta coefficients than the Go condition, whereas the CPT and GNG paradigms differed mainly in the delta band. These results suggest that theta component reflects response inhibition in both GNG and CPT, whereas delta component reflects the more demanding sustained attention requirement of the CPT. The latency prolongation observed with the NoGo condition of the CPT paradigm was thought to be due to perseverance/inhibition conflict enhanced by the primer stimuli in CPT.  相似文献   
24.

Purpose  

To compare the outcomes of percutaneous nephrolithotomy (PCNL) in 2 age groups.  相似文献   
25.
OBJECTIVE: To compare the effectiveness of paper-patch, fat, and perichondrium myringoplasty in the treatment of chronic tympanic membrane perforations smaller than 3 mm. SUBJECTS AND METHODS: This investigation included 45 patients with chronic tympanic membrane perforations smaller than 3 mm. The patients were equally divided into 3 main groups according to surgical procedures. Each group consisted of 3 subgroups, which had 1-mm, 2-mm, and 3-mm perforations. The patients underwent paper-patch, fat, or perichondrium myringoplasty via transcanal approach under local anesthesia. Healing of perforation, hearing improvement, and complications were investigated. RESULTS: Closure rates of the perforations in the paper-patch, fat, and perichondrium myringoplasty groups were 66.7%, 86.7%, and 86.7%, respectively. There were no statistically significant differences in tympanic membrane closure rates between techniques with regard to size. CONCLUSION: Three techniques were found to be feasible for tympanic membrane perforations smaller than 3 mm.  相似文献   
26.
Simultaneous dorsal dislocation of both interphalangeal joints in one finger is an uncommon injury. This injury usually occurs on the ulnar side of the hand involving ring and little fingers. We report a case of simultaneous dislocation of both interphalangeal joints in the middle finger with small avulsion fractures. Closed reduction and splinting in ‘intrinsic plus position’ provided a good result with full range of motion by 8 weeks after the initial injury.  相似文献   
27.
Although posterior urethral valves are predominant as a cause of obstructive uropathy in children, anterior urethral valves may also appear as the underlying etiologic factor in end-stage renal disease that results from obstruction. Two cases are presented of anterior urethral valve patients that were admitted with end-stage renal disease. The first case was successfully treated with diverticulectomy and urethral reconstruction in preparation for renal transplantation. The second case, however, had been on cystostomy drainage for 6 years and also had a contracted bladder. A more extensive lower urinary tract reconstruction was delayed. Children with poor stream and recurrent infections should be evaluated carefully and anterior urethral valve or diverticula should be considered in differential diagnosis of obstructive lesions.  相似文献   
28.
Fistula-in-ano is a common surgical problem. Various materials have been used to perform the seton technique in the treatment of fistula-in-ano. In this study, a novel material, a self-locking cable tie, was used regardless of the fistula type. Seventeen consecutive patients with anal fistula underwent surgery with the cutting seton technique using the novel material. Nine patients had high fistulas. The average tightening was 3.18, the mean fall-out time was 17.41 days, and the mean follow-up period was 8.2 months. No recurrences or incontinence were recorded. There are statistically significant differences between superficial and high fistula cases regarding the number of setons tightening, seton fall-out time, and complete healing time. The novel material presented here has some advantages: it is cheap, easily available, and easily applied, moreover, a gradual tightening can be performed. We think this novel material is a good choice in the treatment of fistula-in-ano.  相似文献   
29.
Cisplatin, an effective antineoplastic agent, frequently induces acute renal failure in animals and humans. Hyperbaric oxygen (HBO) has been shown to prevent cisplatin-induced nephrotoxicity in rats. This study investigated the effect of two different HBO regimes on renal functions, oxidative stress, and histopathological changes in rat kidneys after cisplatin treatment. Wistar rats were divided into five groups: control, HBO, cisplatin, cisplatin plus once daily HBO, and cisplatin plus twice daily HBO. Cisplatin was given as a single intraperitoneal dose of 6 mg/kg, and HBO was applied for 60 min at 2.5 atm for six days. HBO alone did not alter any biochemical parameters or histopathological findings compared with the control group. Cisplatin increased serum urea and creatinine levels and caused severe histopathological injury. In addition, cisplatin increased lipid peroxidation and impaired superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in kidney tissue. Once daily HBO after cisplatin treatment slightly reduced serum urea and creatinine levels and attenuated histopathological injury. HBO also reduced lipid peroxidation and increased SOD and GSH-Px activities significantly. Although twice daily HBO was determined to be more effective than once daily HBO on oxidative stress parameters, it increased serum creatinine levels and histopathological injury compared with the cisplatin group. It was concluded that HBO alone does not induce nephrotoxicity and oxidative stress in rat kidneys; once daily HBO may prevent cisplatin-induced nephrotoxicity, an effect that is partially mediated by the modification of oxidant/antioxidant systems in the kidneys; and twice daily HBO potentiates cisplatin nephrotoxicity by a ROS-independent mechanism.  相似文献   
30.
Necrotizing fasciitis (NF) is uncommon and difficult to diagnose, and it cause progressive morbidity until the infectious process is diagnosed and treated medically and surgically. The literature addressed NF contains confusing information, inaccurate bacteriologic data, and antiquated antibiotic therapy. A delay in diagnosis is associated with a grave prognosis and increased mortality. The main goal of the clinician must be to establish the diagnosis and initially treat the patient within the standard of care. This review is planned as a guide for the clinician in making an early diagnosis of NF and initiating effective medical and surgical therapy.  相似文献   
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