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131.

Introduction

The aim of our study is to establish a reliable neonatal rat model by formula feeding only for evaluation of early surgical intervention on the course of experimental necrotizing enterocolitis (NEC).

Material and methods

Newborn Sprague–Dawley rats were divided into 50 breast-fed (group 1) and 38 formula fed (Similac/Esbilac, group 2) animals. The pups were sacrificed on the 4th, 5th, and 6th day of life and the terminal intestine examined for macroscopic and histologic changes as well as cytokine expression.

Results

The histological mucosal damage was significantly higher of group 2 compared to group 1. The area of the vital mucosa of group 2 was significantly (58.57%, p < 0.001) lower compared to group 1 (75.12%). The mRNA expression of the inflammatory cytokines IL-6, IL-8 and COX-2 was significantly 2-, 5- and 10-fold increased in group 2 compared to group 1.

Discussion

Formula fed newborn rats displayed an inflammatory enterocolitis similar to human NEC. Our study demonstrates a significant loss of mucosa in animals with NEC having increased expression levels of IL-6, IL-8 and COX-2. Mucosal loss appears to be a distinct feature of experimental NEC and has to be correlated with the human disease.  相似文献   
132.
BackgroundThe role of shunting and patching during carotid endarterectomy remains controversial.MethodsThis is a retrospective case series evaluating consecutive patients undergoing carotid endarterectomy with routine shunting and patching. The primary endpoints were perioperative stroke, arterial injury, and lesion recurrence by duplex.ResultsOf the 220 operations performed, 43% were for symptomatic disease. Successful shunt placement occurred in 98%, with no shunt-related injuries. There was 1 minor perioperative stroke and no major strokes. At a mean follow-up of 24 months (median = 12 months), there was 1 restenosis potentially related to shunt placement. The incidence of asymptomatic >50% stenosis in the patched segment was 8%.ConclusionsA combined policy of routine shunting and patching simplifies intraoperative decision making with results that rival or exceed those of trials in which their use was not standardized. Shunts need not be avoided because of concern of arterial injury.  相似文献   
133.
The gap junction protein, connexin43 (Cx43) controls both bone formation and osteoclastogenesis via osteoblasts and/or osteocytes. Cx43 has also been proposed to mediate an anti-apoptotic effect of bisphosphonates, potent inhibitors of bone resorption. We studied whether bisphosphonates are effective in protecting mice with a conditional Cx43 gene deletion in osteoblasts and osteocytes (cKO) from the consequences of ovariectomy on bone mass and strength. Ovariectomy resulted in rapid loss of trabecular bone followed by a slight recovery in wild type (WT) mice, and a similar degree of trabecular bone loss, albeit slightly delayed, occurred in cKO mice. Treatment with either risedronate (20μg/kg) or alendronate (40μg/kg) prevented ovariectomy-induced bone loss in both genotypes. In basal conditions, bones of cKO mice have larger marrow area, higher endocortical osteoclast number, and lower cortical thickness and strength relative to WT. Ovariectomy increased endocortical osteoclast number in WT but not in cKO mice. Both bisphosphonates prevented these increases in WT mice, and normalized endocortical osteoclast number, cortical thickness and bone strength in cKO mice. Thus, lack of osteoblast/osteocyte Cx43 does not alter bisphosphonate action on bone mass and strength in estrogen deficiency. These results support the notion that one of the main functions of Cx43 in cortical bone is to restrain osteoblast and/or osteocytes from inducing osteoclastogenesis at the endocortical surface.  相似文献   
134.

Background

Management of endoscopic retrograde cholangiopancreatography (ERCP)–associated duodenal perforation remains controversial. Some recommend surgery, while others recommend conservative treatment.

Methods

A retrospective chart review was conducted to identify patients treated at our institution for ERCP-related duodenal perforations. Study variables included indication for ERCP, clinical presentation, diagnostic procedures, time to diagnosis and treatment, location of injury, management, length of stay in hospital and survival.

Results

Between January 2000 and October 2009, 12 232 ERCP procedures were performed at our centre, and perforation occured in 11 patients (0.08%; 5 men, 6 women, mean age 71 yr). Six of the perforations were discovered during ERCP; 5 required radiologic imaging for diagnosis. Three perforations were diagnosed incidentally by follow-up ERCP. In 1 patient, perforation occurred 3 years after the procedure owing to a dislocated stent. Four of 11 perforations were stent-related; in 2 patients ERCP was performed in a nonanatomic situation (Billroth II gastroenterostomy). Free peritoneal perforation occurred in 4 patients; 1 was successfully managed conservatively. Four patients (36%) were treated surgically and none died. Five patients were managed conservatively with a successful outcome, and 2 patients died after conservative treatment (18%). Operative treatment included hepaticojejunostomy and duodenostomy (1 patient), suture of the perforation with T-drain (1 patient) and suture only (2 patients). The mean length of stay in hospital for all patients was 20 days.

Conclusion

Post-ERCP duodenal perforations are associated with significant morbidity and mortality. Immediate surgical evaluation and close monitoring is needed. Management should be individually tailored based on clinical findings only.  相似文献   
135.
BackgroundCurrent and previous psychopathology in bariatric surgery candidates is believed to be common. Accurate prevalence estimates, however, are difficult to obtain given that bariatric surgery candidates often wish to appear psychiatrically healthy when undergoing psychiatric evaluation for approval for surgery. Also, structured diagnostic assessments have been infrequently used.MethodsThe present report concerned 199 patients enrolled in the Longitudinal Assessment of Bariatric Surgery study, who also participated in the Longitudinal Assessment of Bariatric Surgery-3 psychopathology substudy. The setting was 3 university hospitals, 1 private not-for-profit research institute, and 1 community hospital. All the patients were interviewed independently of the usual preoperative psychosocial evaluation process. The patients were explicitly informed that the data would not be shared with the surgical team unless certain high-risk behaviors, such as suicidality, that could lead to adverse perioperative outcomes were reported.ResultsMost of the patients were women (82.9%) and white (nonwhite 7.6%, Hispanic 5.0%). The median age was 46.0 years, and the median body mass index was 44.9 kg/m2. Of the 199 patients, 33.7% had ≥1 current Axis I disorder, and 68.8% had ≥1 lifetime Axis I disorder. Also, 38.7% had a lifetime history of a major depressive disorder, and 33.2% had a lifetime diagnosis of alcohol abuse or dependence. All these rates were much greater than the population-based prevalence rates obtained for this age group in the National Comorbidity Survey–Replication Study. Also, 13.1% had a lifetime diagnosis and 10.1% had a current diagnosis of a binge eating disorder.ConclusionThe current and lifetime rates of psychopathology are high in bariatric surgery candidates, and the lifetime rates of affective disorder and alcohol use disorders are particularly prominent. Finally, binge eating disorder is present in approximately 1 in 10 bariatric surgery candidates.  相似文献   
136.
目的 评价中心静脉压(CVP)联合全心舒张末容积指数(GEDVI)指导感染性休克患者容量治疗的效果.方法 感染性休克患者23例,性别不煨,年龄18~64岁,休克时间<6h,急性生理和慢性健康状况评分13~31分,采用随机数字表法,将其随机分为2组:CVP指导容量治疗组(Ⅰ组,n=12)和CVP联合GEDVI指导容量治疗组(Ⅱ组,n=11).2组均静脉输注生理盐水和6%羟乙基淀粉200/0.5,晶体液和胶体液的比例为1∶(0.5 ~ 1.0),输注速率800~ 1600 ml/h,容量治疗过程中Ⅰ组维持CVP8~ 12mmHg;Ⅱ组维持CVP>8 mm Hg和GEDVI 600 ~ 750 ml/m2.分别于容量治疗前及容量治疗开始后6h时采集动脉及中心静脉的血样,测定血乳酸浓度和中心静脉血氧饱和度(ScvO2),计算乳酸和ScvO2的变化率.结果 与Ⅰ组比较,Ⅱ组乳酸变化率升高(P<0.05),ScvO2变化率差异无统计学意义(P>0.05).结论 与CVP指导容量治疗比较,CVP联合GEDVI指导感染性休克患者容量治疗时可增加组织灌注,其效果较好.  相似文献   
137.
目的 探讨改良颈腮腺入路在高位咽旁间隙良性肿瘤手术中的应用疗效。 方法 7例咽旁间隙良性肿瘤患者,术前影像学检查提示为高位、肿瘤巨大、哑铃型且边界欠清,采用改良颈腮腺入路术式,解剖辨认面神经总干及颞面干后,于外耳道软骨前方、腮腺的后缘以及颞面干的上方间隙向深部分离至肿瘤上极,剥离子分离并下压肿瘤与下方常规颈部自下而上肿瘤游离会师后,从颌下区取出肿瘤。腮腺浅叶不切除,面神经分支不做过多解剖。 结果 所有患者均一次性完整切除肿瘤;术后病理示多形性腺瘤6例,神经鞘瘤1例;术中出血均少于300 mL;1例患者出现术后同侧眼睑轻度闭合障碍,两周后完全正常;所有患者面容美学保存理想。 结论 对于高位咽旁间隙良性肿瘤采用改良颈腮腺入路术式,不仅可以安全完整地切除肿瘤,同时由于减少了面神经及腮腺浅叶的处置,术后相关神经并发症及腮腺区凹陷性改变的发生率下降。  相似文献   
138.
139.
Creating prefabricated flaps using tissue expanders in combination with the implantation of maximal blood flow vascular pedicles into suitable tissue areas represents a new tendency in the reconstruction of large skin defects. In 42 Chinchilla Bastard female rabbits weighing 3,700-4,600 g, skeletonized arteriovenous pedicles with maximal blood flow, dissected from the femoral and saphena magna bundles, were implanted underneath abdominal fasciocutaneous flaps. Oval tissue expanders of 250 ml were placed and fixed on the abdominal wall to expand these prefabricated flaps. The evaluation parameters were macroscopic observation, blood analysis, selective microangiography, histology, and scintigraphy. The study results showed that neovascularization in expanded prefabricated flaps was established from newly formed vessels generated from the implanted pedicles and their vascular connections with the originally available vasculature in the flap. After 20 days of prefabrication, the entirety of the expanded prefabricated flaps was perfused by blood flow supplied from newly implanted arteriovenous pedicles. The study indicated that an expanded prefabricated flap can be successfully created by the simultaneous implantation of a maximal blood flow pedicle in combination with flap expansion.  相似文献   
140.
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