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81.
Matteus A M Linsen Vincent Jongkind Laurens Huisman Kak K Yeung Jeroen Diks Willem Wisselink 《Journal of endovascular therapy》2007,14(1):39-43
PURPOSE: To examine the feasibility of a direct videoscopic approach to the descending thoracic aorta for endograft delivery to the aortic arch. METHODS: A double purse-string suture was placed on the aorta of 3 pigs via a thoracoscopic approach. Subsequently, the aorta was cannulated in the center of the purse-string. A 22-F delivery catheter was advanced under fluoroscopic control over a guidewire via a trocar into the proximal aorta. After deployment of a tubular endograft, the catheter was withdrawn from the aorta while simultaneously tightening the purse-string suture, without aortic cross clamping. The outcome was evaluated by post implant angiography and autopsy results. RESULTS: The procedure was successfully completed in all animals, with a mean total procedure time of 126 minutes (range 118-137). Mean endograft implantation time from needle puncture to catheter extraction was 27 minutes (range 21-37). Hemostasis was obtained in all animals after withdrawal of the delivery catheter and tightening the purse-string suture. The mean blood loss was 143 mL (range 80-220). Autopsy proved all purse-string sutures to be adequately placed and all endografts deployed in the correct position. CONCLUSION: A direct videoscopic approach to the descending thoracic aorta proved a feasible technique for endograft delivery to the aortic arch in a porcine model. 相似文献
82.
83.
Antony S. Walton Stephen N. Oesterle Alan C. Yeung 《Catheterization and cardiovascular interventions》1995,34(2):142-146
We report a case of progressive right coronary artery dissection complicating direct angioplasty for an acute inferior myocardial infarct, with successful bail-out stenting of the affected vessel. 相似文献
84.
Rajagopalan Ravi Julio A Rodriguez-Lopez Edwina A Trayler Deborah A Barrett Venkatesh Ramaiah Edward B Diethrich 《Journal of endovascular therapy》2006,13(2):244-248
PURPOSE: To evaluate the effectiveness of endovenous treatment of symptomatic varicose veins using the endovenous laser (EVL) or radiofrequency (RF) energy over a >3-year follow-up. METHODS: From February 2002 to August 2005, 981 consecutive patients (770 women; mean age 51 years, range 15-90) with symptomatic varicose veins in 1250 lower limbs underwent endovenous ablation of 1149 great saphenous veins (GSV) and 101 small saphenous veins (SSV) under tumescent anesthesia without intravenous sedation or regional anesthesia. There were 990 GSV and 101 SSV procedures using EVL; 159 GSVs were treated with RF energy. An ultrasound evaluation was performed within 2 weeks of the procedure to evaluate occlusion of the vein, wall thickness, and clot extension into the deep venous system. Follow-up from the first 200 procedures in the series included clinical evaluation and duplex ultrasound scanning at 6 and 12 months and annually thereafter. RESULTS: Of the 1149 GSVs treated, 39 (3.4%) recanalizations were seen in 33 of the EVL and 6 of the RF procedures for inadequate treatment as judged by ultrasound. There were 9 (9.0%) failures among the 101 SSVs treated with EVL. Overall, both EVL and RF procedures were well tolerated, with only minor complications. One obese patient with ulcer developed pulmonary embolus on the fourth postoperative day. There were no differences between EVL and RF in efficacy or complications. Follow-up at a mean 3 years (range 30- 42 months) in 143 treated limbs showed no neovascularization in the groin. CONCLUSION: Outcomes with EVL and RF were good, with low complication rates that may be related to the use of local tumescent anesthesia without intravenous sedation. 相似文献
85.
Dr. Daisy Saw MD Ernest Pitman MD Maung Maung MD Panas Savasatit MD Daniel Wasserman MD C. K. Yeung MD 《Digestive diseases and sciences》1996,41(2):322-325
Summary A wide variety of diseases and injuries can cause granulomatous hepatitis, and drug-induced granulomatous hepatitis is a well-described entity. Sulfonylurea derivatives, which are commonly used oral hypoglycemic agents in the treatment of non-insulin-dependent diabetes mellitus, have been implicated in liver disease. However, glyburide, a second-generation sulfonylurea and a potent hypoglycemic drug, is considered to have less hepatic side effects than chlorpropamide. It has been reportedly associated with cholestatic jaundice and hepatitis and with hypersensitivity angiitis. A case of necrotizing granuloma has been reported. We present a second case of granulomatous hepatitis occurring in a patient who had been taking glyburide for approximately three years, and we review the literature for glyburide-associated hepatitis. 相似文献
86.
I.Stanley Anderson Kai-Yiu Yeung Diane Hillman Lawrence S. Lessin 《The American journal of medicine》1975,59(4):568-574
Described here is a case of multiple myeloma in a patient with sickle cell anemia. Viscometric studies were made by comparing the patient's whole blood, plasma and washed red blood cells with those of a normal control subject and a patient with sickle cell anemia. Results showed that the increased viscosity of the patient's whole blood as compared with that of the control patient with sickle cell anemia was mainly due to erythrocytic Interaction with the circulating abnormal immunoglobulin. It is postulated that the increased frequency of vaso-occlusive crisis that occurred in our patient in the months before the diagnosis and treatment of multiple myeloma, was due to this cell-protein interaction with the resulting enhancement of whole blood viscosity and the sickling phenomena. 相似文献
87.
The in vitro steroidogenic capacity of the gonadal tissue in the protandrous Rhabdosargus sarba was studied. Testicular and ovarian tissues from various sexual phases were used either separately or combined. With progesterone as precursor, high yield of 5 beta-reduced metabolites, and no 11-ketotestosterone or 11 beta-hydroxytestosterone were found. The production of 5 beta-pregnan-3 alpha-ol-20-one and 5 beta-pregnane-3,20-dione was very high in incubations with testicular tissue from intersexes or males and was low in those with ovarian tissue only. The production of 17 alpha-hydroxyprogesterone was high in the female but was low in other sexual phases. With testosterone as precursor, 11-ketotestoterone and 11 beta-hydroxytestosterone were identified. The latter was the most abundant and prominent polar steroid in all incubations. 5 beta-Reductase activity was high in the male and relatively low in the female. 5 alpha-Reduced products, however, were absent. There was an increase in the production of androstenedione as the animal underwent sex reversal. The significance of this change in steroidogenesis in this protandrous fish is at present under investigation. Experimental results also indicated that in the intersexual gonad there may be interaction between the testicular component and the ovarian component in steroidgenesis. 相似文献
88.
An alarmingly high prevalence of diabetic nephropathy in Asian type 2 diabetic patients: the MicroAlbuminuria Prevalence (MAP) Study 总被引:6,自引:0,他引:6
Wu AY Kong NC de Leon FA Pan CY Tai TY Yeung VT Yoo SJ Rouillon A Weir MR 《Diabetologia》2005,48(1):17-26
Aim/hypothesis Microalbuminuria represents the earliest clinical evidence of diabetic nephropathy and is a marker of increased cardiovascular morbidity and mortality. Its early detection allows the implementation of individualised and aggressive intervention programmes to reduce cardiovascular risk factors. There is limited information on the prevalence of microalbuminuria among hypertensive type 2 diabetic patients in Asia.Methods This cross-sectional epidemiological study aimed to assess the prevalence of microalbuminuria and macroalbuminuria among consecutively screened hypertensive type 2 diabetic adult patients in 103 centres in 10 Asian countries or regions. Predictive factors for microalbuminuria and macroalbuminuria were characterised using a stepwise logistic regression model.Results A total of 6,801 patients were enrolled and 5,549 patients constituted the per-protocol population (patients with bacteriuria and haematuria were excluded). The prevalence of microalbuminuria was 39.8% (39.2–40.5; 95% CI) and the prevalence of macroalbuminuria was 18.8% (18.2–19.3; 95% CI). Only 11.6% of the patients had systolic and diastolic blood pressure below the 130/80 mm Hg target. In the multivariate analyses, the predictive factors for the presence of microalbuminuria were age, BMI, systolic blood pressure and ethnic origin. The highlighted predictive factors for the presence of macroalbuminuria were age, sex, ethnic origin, BMI, duration of diabetes, presence of diabetic complications, intake of diuretics, intake of calcium channel blockers, diastolic and systolic blood pressure.Conclusions/interpretation The high prevalence (58.6%) of micro or macroalbuminuria observed in these patients is alarming and indicates an impending pandemic of diabetic cardiovascular and renal diseases in Asia with its potential economic consequences.A.Y.T. Wu, F.A. de Leon and M.R. Weir received honoraria for speaking engagements and A. Rouillon is employed by Sanofi-Synthelabo Groupe. 相似文献
89.
John Hicks Andrew De Jong James Barrish Shen-Hua Zhu Edwina Popex 《Ultrastructural pathology》2013,37(1):79-83
Kniest dysplasia is an autosomal-dominant chondrodysplastic condition characterized by disproportionate dwarfism, short trunk, small pelvis, kyphoscoliosis, short limbs, prominent joints, premature osteoarthritis, and craniofacial manifestations. The craniofacial abnormalities include tracheomalacia, midface hypoplasia, cleft palate, early onset myopia, retinal detachment, prominent eyes, and sensorineural hearing loss. Radiologic features include dumbbell-shaped femora, platyspondylia with anterior wedging of vertebral bodies, coronal clefts of thoracolumbar vertebral bodies, low broad ilia, and short tubular bones with broad metaphyses and deformed large epiphyses. This form of chondrodysplasia is associated with mutations in type II collagen splicing sequences. Mutations have been identified in the COL2A1 (type II collagen) gene between exons 12 and 24. Type II collagen is the predominant structural protein in cartilage, and mutations in this collagen account for the Kniest dysplasia phenotype. Histopathologic and ultrastructural features of epiphyseal plate cartilage have been described, but tracheal cartilage in an affected neonate has not been examined. The authors report the histopathologic and ultrastructural findings of anterior tracheal cartilage from a 35-day-old female with suspected chondrodysplasia who had tracheomalacia with airway obstruction. The tracheal cartilage was moderately cellular, but lacked cystic and myxoid changes in its matrix. The chondrocytes had abundant cytoplasmic PAS-positive inclusions. Some of these inclusions were diastase-resistant and were also highlighted on Alcian blue staining. Ultrastructural examination revealed chondrocytes with greatly dilated rough endoplasmic reticulum containing granular proteinaceous material. There were also frequent aggregates of typical glycogen. The defect in the COL2A1 gene is secondary to mutations, especially at splice junctions, and this markedly disrupts triple helix formation. The mutated type II procollagen results in intracellular retention within the chondrocytes, as abundant granular proteinaceous material within the dilated RER. A relationship is known to exist between the proportion of mutated to normal type II collagen in the matrix and the severity of the phenotype. With low levels of normal type II collagen, the phenotypic manifestations become more severe, such as in achondrogenesis type II. Both the quantity and quality of type II collagen modulates the phenotypic expression of type II collagenopathies. 相似文献
90.
Diana M.Y. Chiu Martin C.W. Chan Apple C.M. Yeung Karry L.K. Ngai Prof. Paul K.S. Chan MD 《Journal of medical virology》2013,85(3):459-461
The public health impact of hepatitis E virus (HEV) infection varies across the world. An HEV vaccine has been recently approved for clinical use in China. Population‐specific seroprevalence data are essential for cost‐effective assessment of vaccination programs. Here, a cross‐sectional study was performed to provide an update on the local seroprevalence of HEV. An archive of serum samples submitted for virological investigation between 2008 and 2009 to a general hospital was used. A total of 450 samples with equal numbers from each gender covering the age groups from 1–10 to >80 years (25 samples per group) were tested for HEV immunoglobulin G (IgG) by enzyme‐linked immunoassay. Age‐ and gender‐specific seroprevalence were determined. The HEV IgG positive rate increased from 8% among 1–10 years to 56% among >80 years. The increase in prevalence was constant throughout all age groups without a steeper slope or plateau observed from any age group. The overall positive rate among males was significantly higher than among females (32.9% vs. 24.4%, P = 0.048). The best‐fitted seroprevalence curves also suggested a higher positive rate for males across all age groups. Increased HEV IgG positivity was noted in comparison with historical local studies. Collectively, the prevalence of HEV in Hong Kong has increased over the past decade. A large proportion of the population is still susceptible to infection, and all age groups are at risk. Territory‐wide vaccination program should be considered. J. Med. Virol. 85:459–461, 2013. © 2012 Wiley Periodicals, Inc. 相似文献