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91.
92.
Michael J. Hickey Kenneth R. Knight Diana A. Lepore John V. Hurley Wayne A. Morrison 《Microsurgery》1996,17(9):517-523
The aim of this study was to determine whether the administration of free radical antagonists, immediately before and during the early minutes of reperfusion, improves muscle survival 24 hr after a period of ischemia. Rabbit rectus femoris muscles were isolated, made ischemic for 3½ hr and treated with either desferrioxamine (DFX), an Fe3+ chelator, superoxide dismutase and catalase (SOD & CAT), which quench superoxide and hydrogen peroxide, or allopurinol, an inhibitor of xanthine oxidase (XO). After 24 hr reperfusion, muscle viability (±s.e.m.), measured by the nitro blue tetrazolium (NBT) vital staining technique, was 41.6 ± 11.3% for saline-treated ischemic controls, 30.6 ± 7.6% for DFX-treated, 46.7 ± 10.3% for SOD & CAT-treated, and 43.3 ± 9.5% for allopurinol-treated muscles. None of the treated groups differed significantly from the ischemic control group. Tissue myeloperoxidase, ATP and reduced glutathione levels, and plasma lactate dehydrogenase (LDH) and aspartate transaminase (AST) levels were increased by ischemia and reperfusion in all groups, but the changes did not differ between the treatment groups. Levels of XO in the rabbit muscle were determined and found to be very low in both normal and postischemic muscle. As XO is the target enzyme of allopurinol, its absence provides a basis for the lack of effect of this agent. However, it is not clear why DFX and SOD & CAT had no protective effect © 1997 Wiley-Liss, Inc MICROSURGERY 17:517–523 1996 相似文献
93.
We conducted a prospective trial to identify organisms colonizing the urethra and prostate and their role in the aetiology of infection after prostatectomy. Twenty-five patients were studied of whom six developed postoperative infection. The causative organisms were previously recovered from the urethra but not the prostate. There was a high rate of urethral colonization by streptococci (14/25) and a low incidence of prostatic colonization. We describe a novel method of sampling the prostate. 相似文献
94.
95.
Background Hereditary pancreatitis is an important cause of chronic pancreatitis, which may result in endocrine and exocrine failure.
This may necessitate simultaneous pancreas and kidney transplant (SPK). Bladder drainage of the exocrine secretions may cause
problems.
Aim To report one such case and its surgical correction.
Methods A 20-year-old male with insulin-dependent diabetes mellitus secondary to idiopathic chronic pancreatitis had a SPK with bladder
drainage. Urological and metabolic complications secondary to the drainage of pancreatic secretions, rich in proteolytic enzymes
required convertion from bladder to enteric drainage.
Results He was able to discontinue his pancreatic enzyme supplements, ceased to have steatorrhoea and gained weight. He was referred
to the €pean Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer (€PAC), hereditary pancreatitis was confirmed
by genetic analysis.
Conclusion Enteric-drained pancreas transplantation is a successful treatment for exocrine as well as endocrine pancreatic failure and
should be considered as a treatment option in patients with chronic pancreatitis. 相似文献
96.
Edward J. Hickey Brian W. McCrindle Eugene H. Blackstone Thomas Yeh Jr. Frank Pigula David Clarke Christo I. Tchervenkov John Hawkins the CHSS Pulmonary Conduit Working Group 《European journal of cardio-thoracic surgery》2008,33(5):890-898
Objective: Limited availability and durability of allograft conduits require that alternatives be considered. We compared bovine jugular venous valved (JVV) and allograft conduit performance in 107 infants who survived truncus arteriosus repair. Methods: Children were prospectively recruited between 2003 and 2007 from 17 institutions. The median z-score for JVV (n = 27, all 12 mm) was +2.1 (range +1.2 to +3.2) and allograft (n = 80, 9–15 mm) was +1.7 (range −0.4 to +3.6). Propensity-adjusted comparison of conduit survival was undertaken using parametric risk-hazard analysis and competing risks techniques. All available echocardiograms (n = 745) were used to model deterioration of conduit function in regression equations adjusted for repeated measures. Results: Overall conduit survival was 64 ± 9% at 3 years. Conduit replacement was for conduit stenosis (n = 16) and/or pulmonary artery stenosis (n = 18) or regurgitation (n = 1). The propensity-adjusted 3-year freedom from replacement for in-conduit stenosis was 96 ± 4% for JVV and 69 ± 8% for allograft (p = 0.05). The risk of intervention or replacement for branch pulmonary artery stenosis was similar for JVV and allograft. Smaller conduit z-score predicted poor conduit performance (p < 0.01) with best outcome between +1 and +3. Although JVV conduits were a uniform diameter, their z-score more consistently matched this ideal. JVV exhibited a non-significant trend towards slower progression of conduit regurgitation and peak right ventricular outflow tract (RVOT) gradient. In addition, catheter intervention was more successful at slowing subsequent gradient progression in children with JVV versus those with allograft (p < 0.01). Conclusions: JVV does match allograft performance and may be advantageous. It is an appropriate first choice for repair of truncus arteriosus, and perhaps other small infants requiring RVOT reconstruction. 相似文献
97.
Xenogeneic transplantation of 300-400 neonatal rat islets (Fischer 344) to the kidney subcapsular site of streptozotocin-induced nonimmunosuppressed diabetic adult mice (C57BL/6ByJ) resulted in a return to normoglycemia in 87% of the recipients. Of the 13 successfully reversed recipients, 5 exhibited graft rejection (hyperglycemia of +250 mg/dl) within 2 weeks posttransplantation, and 2 mice had rejected their rat islets by 3 weeks. The 6 remaining recipients exhibited significantly prolonged survival of the cultured islets: 1 remained reversed until 4 weeks posttransplantation, 2 remained normoglycemic for 5 weeks, in 3 diabetes remained reversed for more than 7 weeks--in one of these animals the disease was reversed for 17 weeks. Transplanted islets were isolated from neonatal rat pancreas during a period in culture that varied from 8 to 17 days. Although morphological integrity of the endocrine cells was confirmed by ultrastructural study, nonendocrine cells were not identifiable within the islets after 8 days of culture. Xenografted islets examined morphologically prior to obtaining physiological evidence of rejection were associated with extensive peripheral lymphocytic accumulation. Modification of islet immunogenicity leading to prolonged xenograft survival may reflect the degree to which the in vitro environment permits the differential survival of endocrine cells while purging the islet of cells initiating the immune response. 相似文献
98.
儿童医院压疮预防项目实施成效 总被引:1,自引:0,他引:1
压疮问题在成人和老年患者照护中备受关注,然而,婴幼儿的压疮也不容忽视[1]。压疮会延长住院天数,提高患病率、再入院率以及增加健康费用。据健康照护改善机构(TheInstituteforHealthcareImprovement,IHI)估计,每年发生压疮的患者约有250万。IHI的"五百万生命运动"项目中,选定压疮作为12个干预项目之一,这12个项目均是依据科学、可靠的指南制定的临床问题的预防方案[2]。压疮会显著延长住院 相似文献
99.
Lisa Merry Anita J Gagnon Isabelle Hemlin Heather Clarke Jason Hickey 《International journal for equity in health》2011,10(1):56
Introduction
The movement of women across international borders is occurring at greater rates than ever before, yet the relationship between migration and women's health has been under-explored. One reason may be difficulty measuring migration variables including country of birth, length of time in country, immigration status, language ability, and ethnicity. A range of social, environmental, cultural, and medical characteristics associated with the pre-, during- and post-migration phases are also important to consider. The objective of this paper is to present challenges and solutions in measuring migration and related variables via survey-like questionnaires administered to international migrant women. 相似文献100.
Whilst use of estrogen-containing hormone therapy (HT) has declined in recent years, it is still used by a significant minority of women and remains the most effective way of treating menopausal vasomotor symptoms and vaginal dryness. Unscheduled vaginal bleeding and spotting is a common unwanted effect of combined HT. This abnormal bleeding is inconvenient and commonly leads to invasive tests to exclude underlying pelvic pathology. The mechanisms underlying unscheduled bleeding with HT are poorly understood and there are no evidence-based treatment options. Relatively few studies have investigated how combined hormone therapy induces changes in the endometrium which may predispose to increased bleeding. The available evidence suggests that combined HT induces changes in endometrial blood vessels and stroma which may increase vascular fragility. An improved understanding of how combined HT changes the endometrium to induce bleeding may lead to targeted therapies to effectively prevent or resolve bleeding in postmenopausal women. This will improve the acceptability of combined HT and have personal benefits for postmenopausal women and financial benefits for healthcare providers. This review will discuss current evidence and potential mechanisms underlying unscheduled bleeding with combined HT. 相似文献