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51.
The main goal of lumenal endoscopic visualization of the colon is to detect mucosal pathologies, which when removed will result in cure or palliation of a disease process. Whereas traditionally endoscopic imaging was performed with fiber-optic technology, currently there are many new methods that improve our visual acuity when evaluating the colon mucosa. Most of these methods are collectively called 'advanced colonic imaging'. The 2 main aims of standard (white light) and advanced colonic imaging are to enhance the superficial mucosal detail (i.e. 'pit pattern') and allow a detailed view of the submucosal capillary pattern, thus potentially improving the detection characterization of pathological lesions. However, the current literature dealing with most methods used for advanced endoscopic imaging of the colon is fraught with many controversial findings which have resulted in opposing views regarding its utility. Whereas some investigators vehemently support the use of most of these methods in routine clinical practice, most experts and practicing endoscopists still refuse to accept that these methods aid in the clinical routine. For now, white light video-colonoscopy and high-definition white light video-colonoscopy will remain the standard endoscopic methods for investigating the colon mucosa until new methods convincingly and clearly prove their superiority over white light endoscopy.  相似文献   
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Heroin is an illicit narcotic abused by millions of people worldwide. In our earlier studies we have shown that heroin intoxication changes the antioxidant status in human brain. In the present work we continued our studies by estimating the effect of heroin abuse on reduced glutathione (GSH) and enzymes related to this cofactor, such as glutathione S-transferase detoxifying electrophilics (GST) and organic peroxides (as Se-independent glutathione peroxidase—GSHPx), and Se-dependent glutathione peroxidase (Se-GSHPx) specific mainly for hydrogen peroxide. Studies were conducted on human brains obtained from autopsy of 9 heroin abusers and 8 controls. The level of GSH and the activity of glutathione-related enzymes were determined spectrophotometrically. The expression of GST pi on mRNA and protein level was studied by RT-PCR and Western blotting, respectively. The results indicated significant increase of GST and GSHPx activities, unchanged Se-GSHPx activity, and decreased level of GSH in frontal, temporal, parietal and occipital cortex, brain stem, hippocampus, and white matter of heroin abusers. GST pi expression was increased on both mRNA and protein levels, however the increase was lower in brain stem than in other regions. Heroin affects all regions of human brain, and especially brain stem. Its intoxication leads to an increase of organic rather then inorganic peroxides in various brain regions. Glutathione S-transferase plays an important role during heroin intoxication, however its protective effect is lower in brain stem than in brain cortex or hippocampus.  相似文献   
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OBJECTIVE: The risk of non-vertebral fractures is increased in men with type 1 diabetes (DM1) but studies have shown only moderately decreased or normal bone mineral density (BMD) in these patients. No previous studies have evaluated hip strength and geometry indices in DM1 patients. This study was therefore designed to characterize associations between BMD, dual X-ray absorptiometry (DXA)-based hip strength indices, metabolic control, and DM1chronic complications. DESIGN AND METHODS: The study was performed on 36 males aged 43.6 +/- 5.1 years with long-lasting DM1 and 36 healthy males matched for age, weight, and height. BMD in lumbar spine, total hip, upper and lower part of the femoral neck, hip axis length, cross-sectional area and moment of inertia (CSMI), and glycated hemoglobin (HbA1c) were measured. RESULTS: DM1 men had decreased spine BMD (P < 0.05) and normal total hip BMD in comparison with controls. Hip geometry and strength indices were comparable in both groups. However, M1 men had decreased CSMI and upper femur BMD but these differences did not reach statistical significance (P = 0.06). BMD changes and hip strength parameters did not correlate with HbA1c. CONCLUSIONS: Middle-aged DM1 men have decreased lumbar spine BMD, normal hip BMD and normal hip strength indices. These changes are not influenced by metabolic control and presence of chronic microvascular complications.  相似文献   
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In the neonatally 6-hydroxydopamine (6-OHDA)-lesioned rat hyperlocomotor activity, first described in the 1970s, was subsequently found to be increased by an additional lesion with 5,7-dihydroxytryptamine (5,7-DHT) (i.c.v.) in adulthood. The latter animal model (i.e., 134 microg 6-OHDA at 3 d postbirth plus 71 microg 5,7-DHT at 10 weeks; desipramine pretreatments) was used in this study, in an attempt to attribute hyperlocomotor attenuation by D,L-amphetamine sulfate (AMPH) and m-chlorophenylpiperazine di HCl (mCPP), to specific changes in extraneuronal (i.e., in vivo microdialysate) levels of dopamine (DA) and/or serotonin (5-HT). Despite the 98-99% reduction in striatal tissue content of DA, the baseline striatal microdialysate level of DA was reduced by 50% or less at 14 weeks, versus the intact control group. When challenged with AMPH (0.5 mg/kg), the microdialysate level of DA went either unchanged or was slightly reduced over the next 180 min (i.e., 20 min sampling), while in the vehicle group and 5,7-DHT (alone) lesioned group, the microdialysate level was maximally elevated by approximately 225% and approximately 450%, respectively--and over a span of nearly 2 h. Acute challenge with mCPP (1 mg/kg salt form) had little effect on microdialysate levels of DA, DOPAC and 5-HT. Moreover, there was no consistent change in the microdialysate levels of DA, DOPAC, and 5-HT between intact, 5-HT-lesioned rats, and DA-lesioned rats which might reasonably account for an attenuation of hyperlocomotor activity. These findings indicate that there are other important neurochemical changes produced by AMPH- and mCPP-attenuated hyperlocomotor activity, or perhaps a different brain region or multiple brain regional effects are involved in AMPH and mCPP behavioral actions.  相似文献   
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BACKGROUND: Chronic renal failure is a disease of the elderly. The elderly are the fastest growing population among dialysis patients and also on waiting lists for kidney transplantation. The objective for this study was to analyze the results of the renal transplantation in recipients elder than 60 years. To minimize the donor variability and bias, a paired kidney analysis was used. METHODS: The older renal transplantation (ORT) group included 44 patients (30 men, 14 women) aged 60 to 72 (mean 64+/-3) years. Their pairs created a younger renal transplantation (YRT) group consisting of 44 patients (30 men, 14 women) aged 14 to 59 (mean 40+/-12) years. RESULTS: Graft function estimated 1 year after transplantation applying abbreviated Modification of Diet in Renal Disease formula was significantly better in ORT (46.8+/-10.2 ml/min) versus YRT (43.7+/-16.8 ml/min). Studied groups (ORT vs. YRT) did not differ significantly with respect to 1-year patient survival (93.2% vs. 95.5%), 1-year graft survival (88.6% vs. 86.3%), 1-year death-censored graft survival (93% vs. 90.1%), and the incidences of delayed graft function and acute rejection. The most common complications noticed after ORT were cardiovascular complications, surgical complications, and infections. CONCLUSIONS: Our single-center results confirm that renal transplantation is a good option of renal replacement therapy in patients older than 60 years. Thorough recipient selection and preparation as well as customized immunosuppressive protocols are particularly important in that group of renal transplant recipients.  相似文献   
58.
The effects of the highly selective histamine H4 receptor antagonists JNJ7777120 and VUF6002 were investigated on the carrageenan-induced inflammation and thermal hyperalgesia in rats. JNJ7777120 (10 and 30 mg/kg, s.c.) and VUF6002 (10 mg/kg, s.c.) significantly reduced paw edema and hyperalgesia provoked by subplantar injection of carrageenan; the effect was evident against the early (2 h) phase of inflammation. An inactive analog of VUF6002, VUF6007 (10 mg/kg, s.c.) slightly aggravated paw edema, while leaving unaltered carrageenan-induced nociception. These findings indicate that histamine H4 receptors participate in the early phase of acute inflammation induced by carrageenan in rats, influencing both edema and thermal hyperalgesia.  相似文献   
59.
Monosomy 1p36 results from a heterozygous deletion of the most distal chromosomal band on the short arm of chromosome 1. Occurring in approximately 1 in 5,000 live births, monosomy 1p36 is the most common terminal deletion observed in humans. Monosomy 1p36 is associated with mental retardation, developmental delay, hearing impairment, seizures, growth impairment, hypotonia, and heart defects. The syndrome is also characterized by several distinct dysmorphic features, including large anterior fontanels, microcephaly, brachycephaly, deep-set eyes, flat nose and nasal bridge, and pointed chin. Several genes have been proposed as causative for individual features of the phenotype. In addition, based upon molecular characterization of subjects with monosomy 1p36, several mechanisms for the generation and stabilization of terminal deletions have been proposed.  相似文献   
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