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OBJECTIVES: We analyzed the methods and outcomes of urethroplasty in men with complex urethral disruptions. METHODS: The medical records of 40 men with complex urethral disruptions were analyzed. Surgical methods were individualized according to stricture location, severity and length of the stricture, bladder neck characteristics and presence of complicating factors. Patients were divided into four groups based on the above characteristics. RESULTS: End-to-end urethroplasty performed in six patients with short bulbar strictures (<3 cm) was successful in all. Elaborated perineal repair was performed in 10 patients with intermediate (3-6 cm) strictures with or without complicating factors. Elaborated perineal repair with urethral substitution was performed in nine patients with long segment stricture (>6 cm). Abdominal transpubic repair was successfully applied to patients with rectourethral fistula or lacerated bladder neck. Success rate of anastomotic urethroplasty was 95% while over all success rate was 85%. CONCLUSION: Guidelines for urethral reconstruction of complex urethral disruptions are predicated on stricture length, location, bladder neck characteristics and associated complicating factors. End-to-end urethroplasty with stricture excision is highly reliable for short strictures for which previous operative repair have failed. Elaborated perineal repair is extremely versatile for intermediate and longer strictures with associated complicating factors. Abdominal transpubic urethroplasty is effective for patients with rectourethral fistula or lacerated bladder neck.  相似文献   
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A file review of 178 male patients with sexual dysfunction revealed that high income, married status, presence of partner at evaluation, and liberal attitude towards sexuality increased the chances of selection for behavioral sex therapy. The outcome of therapy was associated with treatment adherence. Participation of the conjoint unit resulted in lower dropout rates.  相似文献   
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A computational fluid dynamics study of blood flow in the continuous flow ventricular assist device, Prototype No. 3 (CFVAD3), which consists of a 4 blade shrouded impeller fully supported in magnetic bearings, was performed. This study focused on the regions within the pump where return flow occurs to the pump inlet, and where potentially damaging shear stresses and flow stagnation might occur: the impeller blade passages and the narrow gap clearance regions between the impeller-rotor and pump housing. Two separate geometry models define the spacing between the pump housing and the impeller's hub and shroud, and a third geometry model defines the pump's impeller and curved blades. The flow fields in these regions were calculated for various operating conditions of the pump. Pump performance curves were calculated, which compare well with experimentally obtained data. For all pump operating conditions, the flow rates within the gap regions were predicted to be toward the inlet of the pump, thus recirculating a portion of the impeller flow. Two smaller gap clearance regions were numerically examined to reduce the recirculation and to improve pump efficiency. The computational and geometry models will be used in future studies of a smaller pump to determine increased pump efficiency and the risk of hemolysis due to shear stress, and to insure the washing of blood through the clearance regions to prevent thrombosis.  相似文献   
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Cypermethrin, a class II pyrethroid pesticide, is used to control insects in the household and agricultural fields. Despite beneficial roles, its uncontrolled and repetitive applications lead to unintended effects in non-target organisms. Cypermethrin crosses the blood-brain barrier and induces neurotoxicity and motor deficits. Cypermethrin prolongs the opening of sodium channel, a major site of its action, leading to hyper-excitation of the central nervous system. In addition to sodium channel, cypermethrin modulates chloride, voltage-gated calcium and potassium channels, alters the activity of glutamate and acetylcholine receptors and adenosine triphosphatases and induces DNA damage and oxidative stress in the neuronal cells. Cypermethrin also modulates the level of neurotransmitters, including gamma-aminobutyric acid and dopamine. It is one of the most commonly used pesticides in neurotoxicology research not only because of its variable responses depending upon the doses, time and routes of exposure and strain, age, gender and species of animals used across multiple studies but also owing to its ability to induce the nigrostriatal dopaminergic neurodegeneration. This article describes the effect of acute, chronic, developmental and adulthood exposures to cypermethrin in experimental animals. The article sheds light on cypermethrin-induced changes in the central nervous system, including its contribution in the onset of specific features, which are associated with the nigrostriatal dopaminergic neurodegeneration. Resemblances and dissimilarities of cypermethrin-induced nigrostriatal dopaminergic neurodegeneration with sporadic and chemicals-induced disease models along with its advantages and pitfalls are also discussed.  相似文献   
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Type 2 diabetes mellitus (T2DM) accounts for >90% of the cases of diabetes in adults. Resistance to insulin action is the major cause that leads to chronic hyperglycemia in diabetic patients. T2DM is the consequence of activation of multiple pathways and factors involved in insulin resistance and β-cell dysfunction. Also, the etiology of T2DM involves the complex interplay between genetics and environmental factors. This interplay can be governed efficiently by lifestyle modifications to achieve better management of diabetes. The present review aims at discussing the major factors involved in the development of T2DM that remain unfocussed during the anti-diabetic therapy. The review also focuses on lifestyle modifications that are warranted for the successful management of T2DM. In addition, it attempts to explain flaws in current strategies to combat diabetes. The employability of phytoconstituents as multitargeting molecules and their potential use as effective therapeutic adjuvants to first line hypoglycemic agents to prevent side effects caused by the synthetic drugs are also discussed.  相似文献   
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Abstract

Gelatin, chitosan and nano calcium phosphate based composite scaffold with tailored architectures and properties has great potential for bone regeneration. Herein, we aimed to improve the physico chemical, mechanical and osteogenic properties of 3D porous scaffold by incorporation of dihydrogen calcium phosphate anhydrous (DCPA) nanoparticles into biopolymer matrix with variation in composition in the prepared scaffolds. Scaffolds were prepared from the slurry containing gelatin, chitosan and synthesized nano DCPA particle using lyophilization technique. DCPA nano particles were synthesized using calcium carbonate and phosphoric acid in water–ethanol medium. XRD pattern showed phase pure DCPA in synthesized nanopowder. Scaffolds were prepared by addition of DCPA nanoparticles to the extent of 5–10?wt% of total polymer into gelatin–chitosan solution with solid loading varying between 2.5 and 2.75?wt%. The prepared scaffold showed interconnected porosity with pore size varying between 110 and 200 micrometer. With addition of DCPA nanoparticles, average pore size of the prepared scaffolds decreased. With increase in nano ceramic phase content from 5?wt% to 10?wt% of total polymer, the compressive strength of the scaffold increased. Scaffold containing 10?wt% DCPA showed the highest average compressive strength of 2.2?MPa. Higher cellular activities were observed in DCPA containing scaffolds as compared to pure gelatin chitosan scaffold suggesting the fact that nano DCPA addition into the scaffold promoted better osteoblast adhesion and proliferation as evident from MTT assay and scanning electron microscopic (SEM) investigation of osteoblast cultured scaffolds. A higher degree of lamellopodia and filopodia extensions and better spreading behavior of osteoblasts were observed in FESEM micrographs of MG 63 cultured DCPA containing scaffold. The results demonstrated that both mechanical strength and osteogenic properties of gelatin–chitosan scaffold could be improved by addition of anhydrous dihydrogen calcium phosphate nanoparticles into it.  相似文献   
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