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OBJECTIVE: The 'frozen' elephant trunk technique allows for single-stage repair of combined aortic arch and descending aortic aneurysms using a 'hybridprosthesis' with a stented and a non-stented end. This report summarizes the operative- and follow-up data (mean follow-up 14 months) with this new treatment. METHODS: Between 09/01 and 4/04, 22 patients (62+/-9 years; 9 female) with different aortic pathologies (15 aortic dissections, 7 aneurysms) were operated on after approval from the local institutional review board. The stented end of the hybridprosthesis was deployed in the descending aorta through the opened aortic arch during hypothermic circulatory arrest and selective antegrade cerebral perfusion. RESULTS: All patients survived the procedure but one patient died of acute hemorrhage due to rupture of the false lumen in the descending aorta on the second postoperative day. Two patients required reexploration of the chest for bleeding complications. In 2 of 4 patients who developed neurological dysfunction, symptoms resolved completely. In one of them, the descending aorta was perforated intraoperatively due to misplacement of the stented end of the hybridprosthesis. In all follow-up CT-scans thrombus formation in the descending aortic aneurysm excluded by the stented end of the hybridprosthesis has been observed. CONCLUSIONS: This procedure is performed through median sternotomy and combines the concepts of the elephant trunk operation and endovascular stenting of descending aortic aneurysms. Favourable intraoperative and postoperative results during follow-up with regard to thrombus formation around the stented descending aortic segment encourage us to evaluate all patients with thoracic aneurysms extending to proximal and distal of the left subclavian artery for this treatment.  相似文献   
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The human epidermis has the full machinery for autocrine L-phenylalanine turnover to L-tyrosine in keratinocytes and melanocytes. Phenylalanine hydroxylase (PAH) activities increase linearly with inherited skin colour (skin phototype I-VI, Fitzpatrick classification) yielding eightfold more activities in black skin compared to white skin. Moreover, UVB irradiation (1 MED) significantly increases epidermal PAH activities 24 h after exposure. Importantly, L-phenylalanine uptake and turnover in the pigment forming melanocytes is vital for initiation of melanogenesis. In this context it was shown that the uptake of this amino acid is regulated by calcium. The depigmentation disorder vitiligo provides a unique model to follow impaired L-phenylalanine turnover in the skin as well as in serum because affected individuals hold an impaired epidermal 6BH4 de novo synthesis/recycling and regulation including low epidermal PAH activities. After overnight fasting and oral loading with L-phenylalanine (100 mg/kg body weight), 29.6% of 970 patients tested (n=287/970) yielded serum phenylalanine/tyrosine ratios >or=4 and 35.3% (n=342/970) had mild to moderate hyperphenylalaninaemia (HPA), while 9.3% (n=90/970) had both serum L-phenylalanine levels >or=2.0 mg/dl and phe/tyr ratios >or=4.0. Isolated HPA was found in 26% (n=252/970), whereas 20.3% had only increased ratios (n=197/970). None of the patients had phenylketonuria and the family history for this metabolic disease was negative. The IQ followed normal Gaussian distribution. In vitro L-phenylalanine uptake/turnover studies on primary epidermal melanocytes originating from these patients demonstrated a significantly decreased calcium dependent L-phenylalanine uptake and turnover compared to healthy control cells. Based on our observation, we would like to propose that phenylalanine uptake/turnover is under tight control by calcium which in turn could offer an additional novel mechanism in the aetiology of HPA.  相似文献   
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Purpose

To define the clinical and pathological patterns of urinary bladder carcinoma from the University Hospital of Nepal.

Methods

This is a retrospective analytical study. Patients with bladder mass who underwent surgery over 1 year and who had data record were included in the study. Demographic profile, type of surgery, findings on clinical examination, cystoscopy findings, histopathological report, tumor stage, and post-surgery adjuvant therapy were analyzed.

Results

Out of 86 patients who underwent transurethral resection of bladder tumor, 77 patients had biopsy-proven malignant bladder tumor. Urothelial cancer was present in 96.1%. Male were 78.6%. The mean age of diagnosis was 65.5?±?11.8 years. Non-muscle-invasive bladder cancer (NMIBC) was 3.7 times more common than muscle-invasive bladder cancer (MIBC). High-grade tumors (58.6%) were more common than low grade (41.4%). The detrusor muscle was present inthe biopsy specimen of 48 patients (64%). Re-TURBT within 2–6 weeks was considered based on histopathology reports for about half of the patients (45.3%). Upstaging and upgrading of the tumor was present in 5.8 and 5.8% of the patients, respectively. Residual tumor without upstaging and upgrading was present in 23.5%. One patient (1.3%) had Clavien–Dindo grade 1, three (4%) patients had grade 2 and two patients (2.7%) had grade 3b.

Conclusion

In the present study, patients with bladder cancer are younger than reported in other studies. Smokers are strongly predisposed. The histological pattern is similar to the Western and Asian populations. NMIBC and MIBC occur in proportion to that described as in other studies. We had a lower rate of recurrence, upstaging and upgrading. We had a lesser rate of acceptance for radical cystectomy in our patients.

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Tephrosia purpurea (family: Fabaceae), which is used in traditional remedies for the treatment of febrile attacks, enlargement and obstruction of liver, spleen, and kidney, was found to have significant antileishmanial activity, and has been extensively fractionated to locate the abode of activity. A fraction (F062) obtained from N‐butanol extract of T. purpurea showed consistent antileishmanial activity at 50 mg/ kg × 5 days by oral route against Leishmania donovani infection in hamsters. Activity was further confirmed in a secondary model, i.e., Indian langur monkeys (Presbytis entellus). Thus, the fraction F062 from this plant possesses potential to produce significant antileishmanial activity by oral route without producing any toxic side effects. Drug. Dev. Res. 60:285–293, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
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In the present research article, we have developed solid heterogenous silica supported lanthanum trifluoroacetate and trichloroacetate as green Lewis acid catalysts. These catalysts were synthesized by a novel, simple, cheap, clean, and environment friendly method. The physicochemical properties of the prepared catalysts were well studied and characterized by sophisticated spectroscopic techniques such as FTIR, TGA, XRD, EDX, SEM, TEM and BET analysis. The catalyst was utilized in the synthesis of arylimidazole derivatives via green protocols under solvent-free conditions at 70 °C with a higher yield, mild reaction conditions and a short reaction time. The catalyst works superiorly in water as well as in various organic solvents as a reusable and easily recoverable catalyst.

Silica supported lanthanum trifluoroacetate and trichloroacetate as green Lewis acid catalysts were developed by a novel, simple, cheap, and environment friendly method and utilized them in the synthesis of arylimidazole derivatives via one pot solvent-free approach.  相似文献   
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Background/AimTo report 5-year real-world efficacy and safety data following the treatment of chronic diabetic macular oedema (DMO) with the intravitreal 0.19 mg fluocinolone acetonide implant(ILUVIEN).MethodsRetrospective cohort study of 31 eyes treated with ILUVIEN for chronic DMO at a tertiary centre in Birmingham (UK). Best corrected visual acuity (BCVA) and central retinal thickness (CRT) were recorded at baseline, and then at 1-,2-,3-, and 5-years. Safety was assessed based on intraocular pressure (IOP) -lowering medication, surgery, and other complications.ResultsBCVA significantly improved 1-year post-ILUVIEN (+4.2 letters, p < 0.05) and gradually reverted to baseline levels over the 5-year period of follow-up (+0.2 letters at year-5). A significant and sustained CRT reduction was observed throughout the 5-years. The proportion of eyes on IOP-lowering medication increased from 16% at baseline, to 70% at 5-years (p < 0.001) with eyes on a mean of 1.3 medications. Laser trabeculoplasty (n = 2), cyclodiode laser (n = 1), and trabeculoplasty and trabeculotomy (n = 1, in the same eye; 3.2%) were required for uncontrolled IOP. Other complications included endophthalmitis (n = 1) and vitreous haemorrhage (n = 1). 58% of eyes required additional intravitreal injections, with a mean 29.2 months to first injection. We observed a 69% reduction in treatment burden following treatment with ILUVIEN implant.ConclusionsOur real-world results confirm the efficacy of the ILUVIEN implant over 5 years, with two-thirds of eyes having improved or stable visual acuity 5 years after ILUVIEN, and an overall sustained improvement in anatomical outcome. Although the rate of IOP-lowering medications use was higher than previously reported, the rate of incisional IOP-lowering surgery and other complications remained low and in keeping with rates reported in larger studies.Subject terms: Diabetes complications, Drug therapy, Retinal diseases  相似文献   
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