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961.
AIM: To evaluate the outcome and morbidity after major surgical interventions for inflammatory bowel disease (IBD). METHODS: Retrospective case note analysis of 227 children referred to a tertiary referral centre between 1994 and 2002 for treatment of IBD. RESULTS: 26 of 125 children with Crohn's disease (21%) required surgical management. 13 with disease proximal to the left colon underwent limited segmental resections and primary anastomosis, without significant morbidity. Primary surgery for 13 children with disease distal to the transverse colon included 6 subtotal-colectomies or panprocto-colectomies. All seven children undergoing conservative segmental resections (three with primary anastomosis, four with stoma formation), required further colonic resection or defunctioning stoma formation. All three children undergoing primary anastomosis developed a leak or fistula formation. 22 of 102 children with ulcerative colitis (22%) required surgery. Definitive procedures (n = 17) included J-pouch ileoanal anastomosis (n = 11), ileorectal anastomosis (n = 2), straight ileoanal anastomosis (n = 3), and proctectomy/ileostomy (n = 1). Five children await restorative surgery after subtotal colectomy. Median daily stool frequency after J-pouch surgery was 5 (range 3-15), and 10 of 11 children reported full daytime continence. All three children with straight ileoanal anastomosis had unacceptable stool frequency and remain diverted. CONCLUSION: The complication rate after resectional surgery for IBD was 57% for Crohn's disease, and 31% for ulcerative colitis. In children with Crohn's disease, limited resection with primary anastomosis is safe proximal to the left colon. Where surgery is indicated for disease distal to the transverse colon, subtotal or panproctocolectomy is indicated, and an anastomosis should be avoided. Children with ulcerative colitis had a good functional outcome after J-pouch reconstruction. However, the overall failure rate of attempted reconstructive surgery was 24%, largely owing to the poor results of straight ileoanal anastomosis.  相似文献   
962.
Complement, a critical defence against pathogens, has been implicated as a driver of pathology in COVID-19. Complement activation products are detected in plasma and tissues and complement blockade is considered for therapy. To delineate roles of complement in immunopathogenesis, we undertook the largest comprehensive study of complement in COVID-19 to date, comprehensive profiling of 16 complement biomarkers, including key components, regulators and activation products, in 966 plasma samples from 682 hospitalized COVID-19 patients collected across the hospitalization period as part of the UK ISARIC4C (International Acute Respiratory and Emerging Infection Consortium) study. Unsupervised clustering of complement biomarkers mapped to disease severity and supervised machine learning identified marker sets in early samples that predicted peak severity. Compared to healthy controls, complement proteins and activation products (Ba, iC3b, terminal complement complex) were significantly altered in COVID-19 admission samples in all severity groups. Elevated alternative pathway activation markers (Ba and iC3b) and decreased alternative pathway regulator (properdin) in admission samples were associated with more severe disease and risk of death. Levels of most complement biomarkers were reduced in severe disease, consistent with consumption and tissue deposition. Latent class mixed modelling and cumulative incidence analysis identified the trajectory of increase of Ba to be a strong predictor of peak COVID-19 disease severity and death. The data demonstrate that early-onset, uncontrolled activation of complement, driven by sustained and progressive amplification through the alternative pathway amplification loop is a ubiquitous feature of COVID-19, further exacerbated in severe disease. These findings provide novel insights into COVID-19 immunopathogenesis and inform strategies for therapeutic intervention.  相似文献   
963.
目的:以注射用兰索拉唑为对照,评价注射用右兰索拉唑15 mg q12 h治疗急性胃和/或十二指肠溃疡引起的上消化道出血的有效性及安全性。方法:选取全国31家研究中心的急性胃和/或十二指肠溃疡引起的上消化道出血患者共202例,按照1∶1随机分配至试验组(注射用右兰索拉唑组)和对照组(注射用兰索拉唑组)。主要疗效终点为72 h有效止血率。对主要疗效终点采用非劣效评价,非劣效性界值δ是10%。结果:有效性方面,全分析数据集分析结果显示:用药72 h后,注射用右兰索拉唑组有效止血率为96.08%(98/102);注射用兰索拉唑组有效止血率为98.00%(98/100),两组率差为-1.92%(95%CI-6.58,2.74)。两组72 h有效止血率差异无统计学意义(P=0.682 9)。两组率差的双侧界值均低于δ(10%),注射用右兰索拉唑非劣于注射用兰索拉唑。安全性方面,试验组的不良事件及不良反应发生率与对照组差异无统计学意义,无非预期不良反应和严重不良反应。主要的不良反应为白细胞计数降低、中性粒细胞计数降低等。结论:注射用右兰索拉唑15 mg q12 h在治疗急性胃和/或十二指肠溃疡引起的...  相似文献   
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