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51.
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Aim: The purpose of this study was to evaluate the effects of hyperbaric oxygen (HBO) and HBO preconditioning (pre-HBO) on experimental wound healing and tensile strength in the colonic anastomosis of rats. Materials and Methods: A total of 21 Sprague–Dawley rats were divided into three random groups of equal numbers: sham operation, pre-HBO, and HBO. Sham group was given standard left colon resection and end-to-end anastomosis; pre-HBO group received HBO as one dose + colonic resection + anastomosis; HBO group was given colonic resection + anastomosis + HBO. HBO was administrated at 24-hr intervals and relaparatomy was performed on the fifth day. Malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), interleukin (IL)-10, IL-6, tumor necrosis factor-alpha (TNF-α), and hydroxy (OH)-proline levels and anastomotic burst pressure were evaluated. Results: Burst pressure and OH-proline levels markedly increased in the HBO group compared with the sham and pre-HBO groups. When compared with the sham group, MDA and MPO levels were significantly decreased in the HBO and pre-HBO groups. In contrast to these findings, SOD and GSH-Px levels were increased in the HBO group as compared with the sham and pre-HBO groups. TNF-α, IL-6, and IL-10 values were detected at low levels in the HBO group as compared with other groups. Conclusions: HBO administration accelerated wound healing and strengthened the anastomotic tissue. In the light of these results, the HBO administration has beneficial effects and contributed to wound healing in colonic anastomosis. But, as expected, pre-HBO did not alter the results significantly.  相似文献   
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BACKGROUND/AIMS: 5-Fluorouracil-based chemoradiotherapy is the most widely used treatment modality in the adjuvant treatment of rectal cancer. Capecitabine represents a valuable alternative to 5-Fluorouracil in this situation. METHODOLOGY: Patients with stage II and stage III rectal adenocarcinoma, who were included in this analysis, received adjuvant chemoradiotherapy consisting of external-beam radiotherapy (50.4-54Gy) either with 5-Fluorouracil at a median dose of 300 mg/m2/day by protracted venous infusion for 5 days a week, or capecitabine at a median dose of 1650 mg/m2/day for 5 days a week after surgery. The data concerning the toxicity and the efficacy of the treatments were compared in patients treated with 5-Fluorouracil- and capecitabine-based chemoradiotherapy. RESULTS: Forty-three patients received 5-Fluorouracil, and 24 patients received capecitabine during adjuvant radiotherapy. Although there were no differences between the groups in terms of toxicity rates, distant metastasis-free survival, disease-free survival, and overall survival rates; a trend for improved loco-regional recurrence-free survival rate was observed in the capecitabine arm (p = 0.063). CONCLUSIONS: Capecitabine is at least as effective as 5-Fluorouracil in the postoperative treatment of rectal adenocarcinoma. Considering the trend for improved loco-regional recurrence-free survival rate in the capecitabine arm, it seems that the drug exerts better synergy with radiotherapy in this situation.  相似文献   
55.
Objective:To assess the bone support of the teeth adjacent to a cleft using cone-beam computed tomography (CBCT).Materials and Methods:The CBCT scans of 31 patients with unilateral cleft lip and palate (UCLP) were assessed. The data for teeth neighboring the cleft were compared with those of contralateral noncleft teeth. For each tooth analyzed, the distance between the cementoenamel junction (CEJ) and the bone crest (AC) at the buccal side was measured as was the thickness of the buccal bone level at 0, 1, 2, and 4 mm.Results:The bone thicknesses of the central teeth at the cleft region at the crest and 2 mm apically were statistically significantly thinner than that of the central incisor at a noncleft region. The CEJ-AC distance for central teeth at the cleft region was higher than that for central teeth in a noncleft region.Conclusions:Subjects with UCLP showed reduced bone support at teeth neighboring the cleft compared with controls. This may cause some problems during orthodontic treatment.  相似文献   
56.
Poststreptococcal reactive arthritis (PSRA) is an acute, nonsuppurative arthritis following documented streptococcal infections. Although most authors accepted it as a different entity, the differences from acute rheumatic fever (ARF) are not clear. To document and compare the clinical and laboratory characteristics of PSRA and ARF, 24 patients with PSRA and 20 with ARF were enrolled in the study. The latency period from upper respiratory tract infection was shorter in patients with PSRA ( P<0.01). However, 25% of the patients with ARF had also short (<10 days) latency periods. Although symmetric and nonmigratory arthritis were more frequent in patients with PSRA, there was no significant difference for the distribution of mono-, oligo-, and polyarticular disease between PSRA and ARF patients. The frequency of small joint and hip involvement was also similar between the patient groups. Unresponsiveness of articular symptoms to salicylate therapy within 72 h was more frequent in patients with PSRA (P<0.001). However, in a substantial part of the patients with ARF (nine patients, 45%), joint symptoms also had no response during the first 72 h. Since there is a considerable overlap of symptoms, signs, and laboratory features of PSRA and ARF, a line between these two entities could not be easily drawn. We conclude that these two conditions are actually different presentations of the same disease.  相似文献   
57.
Aims/hypothesis. Insulin resistance is recognised as the core factor in the pathogenesis of Type II (non-insulin-dependent) diabetes mellitus, hypertension and atherosclerosis. Several studies indicate the possible role of mutations of the insulin receptor substrate-1 (IRS-1) gene in the pathogenesis of insulin-resistance and suggest a possible interaction between the IRS-1 gene and obesity, either by an effect on the development of obesity or by causing or aggravating the obesity-associated insulin resistance. Therefore, the prevalence of the G972R mutation of the IRS-1 gene was compared in 157 non-diabetic obese subjects (BMI > 30 m/kg2) and in 157 lean subjects (BMI < 28 m/kg2). By investigating the relation between this IRS-1 mutation, measures of obesity and metabolic parameters, we explored the possible influence of this mutation on body fat distribution and insulin resistance. Methods. The G972R mutation was detected by PCR amplification and BstN-1 restriction enzyme digestion. Data were analysed by univariate and multivariate analysis. Results. The G972R allele was significantly more frequent in obese subjects than in lean subjects (p < 0.002); however, no difference was found between centrally and peripherally obese subjects. Obese G972R carriers had significantly higher BMI (p < 0.001), fasting insulin (p < 0.01), triglycerides (p < 0.03) and HOMAIR (p < 0.001) than obese non-carriers. No differences were observed between G972R carriers and non-carriers among control subjects. Multivariate analysis confirmed that the IRS-1 G972R mutation was significantly and independently associated with reduced insulin sensitivity (p < 0.009) in the obese group. Conclusion/interpretation. The G972R mutation of the IRS-1 gene associates with obesity, but not with fat distribution, in this Italian cohort, and within the obese subjects this IRS-1 variant strongly associates with metabolic parameters suggesting greater insulin-resistance. These findings indicate a possible interaction between the IRS-1 variant and obesity in worsening insulin sensitivity. [Diabetologia (2001) 44: 367–372] Received: 11 August 2000 and in revised form: 25 October 2000  相似文献   
58.
[Purpose] This study aimed to investigate the effect of ankle proprioceptive training on static body balance. [Subjects and Methods] In this randomized-controlled, single-blind study, 59 university students (35 females, 24 males) were randomized into study (n=29) and control (n=30) groups. The study group received a foot and ankle proprioceptive exercise program including stretching, strengthening (plantar and dorsi-flexors, invertor and evertor muscles), and balance board exercises, each with 10 repetitions per session, 5 days a week, for a total of 10 sessions. The control group did not receive any intervention. Static body balance was evaluated by a kinesthetic ability trainer, which showed the balance index scores under both single foot and both feet conditions. This evaluation was repeated at the end of two weeks for both groups. [Results] Outcome measures of the groups were similar at the baseline. Balance index scores of both groups improved at the end of two weeks, and the study group had significantly lower index scores than those of the control group, indicating better balance. [Conclusion] Ankle proprioceptive training had positive effects on static body balance parameters in healthy individuals, and it is worth investigating the effects of this type of training in patients with balance disorders.Key words: Ankle proprioception, Static balance, Sport KAT  相似文献   
59.
ObjectiveIn this study, we compared the changes in arterial stiffness in chronic hemodialysis patients treated with 8-h vs. 4-h thrice weekly in-center hemodialysis.MethodsSixty prevalent chronic hemodialysis patients assigned to 8-h nocturnal in-center thrice weekly HD (NHD) and 60 control cases assigned to 4-h thrice weekly conventional HD (CHD) were followed for one year. Radial–carotid pulse wave velocity, augmentation index and echocardiography were performed at baseline and 12th month.ResultsMean age of the patients was 49 ± 11 years, 30.8% were female, 27.5% had diabetes mellitus and mean dialysis vintage was 57 ± 47 months. Baseline demographical, clinical and laboratory parameters were similar between groups. During a mean follow-up of 15.0 ± 0.1 months, blood pressure remained similar in both groups while the number of mean daily anti-hypertensive substances decreased in the NHD group. In the NHD group, time-averaged serum phosphorus and calcium–phosphorus product were lower than the CHD group. Pulse wave velocity and augmentation index decreased in the NHD group (from 11.02 ± 2.51 m/s to 9.61 ± 2.39 m/s and from 28.8 ± 10.3% to 26.2 ± 12.1%; p = 0.008 and p = 0.04, respectively). While augmentation index increased in the CHD group (28.0 ± 9.4 to 31.0 ± 10.7%, p = 0.02), pulse wave velocity did not change. Subendocardial viability ratio and ejection duration improved in the NHD group (from 135 ± 28 to 143 ± 25%, p = 0.01 and from 294 ± 34 ms to 281 ± 34 ms, p = 0.003, respectively), accompanied by regression of left ventricular mass index. In multiple stepwise linear regression analyses, NHD was associated with improvements in augmentation index, ejection duration and subendocardial viability ratio.ConclusionsThese data indicate that arterial stiffness is ameliorated by implementation of longer hemodialysis sessions.  相似文献   
60.
The active site of cytochrome c (Cyt c) consists of a heme covalently linked to a pentapeptide segment (Cys-X-X-Cys-His), which provides a link between the heme and the protein surface, where the redox partners of Cyt c bind. To elucidate the vibrational properties of heme c, nuclear resonance vibrational spectroscopy (NRVS) measurements were performed on (57)Fe-labeled ferric Hydrogenobacter thermophilus cytochrome c(552), including (13)C(8)-heme-, (13)C(5)(15)N-Met-, and (13)C(15)N-polypeptide (pp)-labeled samples, revealing heme-based vibrational modes in the 200- to 450-cm(-1) spectral region. Simulations of the NRVS spectra of H. thermophilus cytochrome c(552) allowed for a complete assignment of the Fe vibrational spectrum of the protein-bound heme, as well as the quantitative determination of the amount of mixing between local heme vibrations and pp modes from the Cys-X-X-Cys-His motif. These results provide the basis to propose that heme-pp vibrational dynamic couplings play a role in electron transfer (ET) by coupling vibrations of the heme directly to vibrations of the pp at the protein-protein interface. This could allow for the direct transduction of the thermal (vibrational) energy from the protein surface to the heme that is released on protein/protein complex formation, or it could modulate the heme vibrations in the protein/protein complex to minimize reorganization energy. Both mechanisms lower energy barriers for ET. Notably, the conformation of the distal Met side chain is fine-tuned in the protein to localize heme-pp mixed vibrations within the 250- to 400-cm(-1) spectral region. These findings point to a particular orientation of the distal Met that maximizes ET.  相似文献   
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