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81.
Role of bacterial translocation in necrotizing enterocolitis   总被引:1,自引:0,他引:1  
The intestinal mucosa functions as a major local defense barrier preventing bacteria that colonize the gut from invading organs and tissues. Under certain circumstances, bacteria colonizing the gastrointestinal tract can cross the gut mucosal barrier to infect the mesenteric lymph node and systemic organs via a process termed bacterial translocation. Factors that promote the translocation of bacteria or endotoxin from the gut include bacterial overgrowth with gram-negative enteric bacilli, impaired host immune defenses and injury to the gut mucosa resulting in increased intestinal permeability. These same promoting factors are present in patients at increased risk of developing necrotizing enterocolitis. Consequently, this review focuses on the potential role of bacterial and endotoxin translocation from the gut in the pathogenesis of necrotizing enterocolitis.  相似文献   
82.
One hundred and twenty eight Brazilian children with lymphoblastic leukaemia were intensively treated with a Berlin-Frankfurt-Munich based protocol. More children had a white cell count above 50 x 10(9)/l (31%) then observed in developed countries. After a median follow up of 31 months (11-58 months), the estimated probability of relapse free survival was 41% (7%) for the whole group. After adjustment in the Cox's multivariate model, malnutrition was the most significant adverse factor affecting duration of complete remission. Age above 8 years and high peripheral white cell count were also significant adverse factors. Among the nutritional indices, the height for age and weight for age z scores were both significant, whether the cut off points of z-2 or z = -1.28 were chosen to define malnutrition. A strong statistical association between the two indices was found; the contribution of height for age z score to the prediction of relapse free survival was more significant. Children with height for age z score < -2 had a relapse risk of 8.2 (95% confidence interval 3.1 to 21.9) relative to children with z score > -2. The results of this study suggest that socioeconomic and nutritional factors should be considered in the prognostic evaluation of children with leukaemia in developing countries.  相似文献   
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Background : In 1993, the Australian Optometrical Association developed competency standards for entry-level to the profession.1 These competencies were the basis for the development of an assessment process to determine suitability for entry to the profession. Methods : The competency standards were ranked in order of importance for assessment. Methods were developed to assess the competencies with a number of methods used to assess more highly ranked competencies. A pilot examination was conducted to test the process. Passes were awarded if the performance of the candidate was suitable for entry-level to the profession. Results : The final examination consisted of: Two written papers (six hours), containing a number of case histories and requiring short answers, were used to assess knowledge in basic and clinical science and application of this knowledge clinically. A ‘diagnosis and management’ paper (two hours), containing photographic information accompanied by case histories, was used to assess ability to interpret information and offer diagnoses and management options. Skills station assessment (three and one-half hours) was used to assess the performance of 21 clinical skills. Clinical examinations were used to assess the performance during a full optometric examination, with the interpretation of results and determination of management plans.  相似文献   
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OBJECTIVE: The aim of this study was to determine whether aggressive management of neuroendocrine hepatic metastases improves survival. SUMMARY BACKGROUND DATA: Survival in patients with carcinoid and pancreatic neuroendocrine tumors is significantly better than adenocarcinomas arising from the same organs. However, survival and quality of life are diminished in patients with neuroendocrine hepatic metastases. In recent years, aggressive treatment of hepatic neuroendocrine tumors has been shown to relieve symptoms. Minimal data are available, however, to document improved survival with this approach. METHODS: The records of patients with carcinoid (n = 84) and pancreatic neuroendocrine tumors (n = 69) managed at our institution from January 1990 through July 2004 were reviewed. Eighty-four patients had malignant tumors, and hepatic metastases were present in 60 of these patients. Of these 60 patients, 23 received no aggressive treatment of their liver metastases, 19 were treated with hepatic resection and/or ablation, and 18 were managed with transarterial chemoembolization (TACE) frequently (n = 11) in addition to resection and/or ablation. These groups did not differ with respect to age, gender, tumor type, or extent of liver involvement. RESULTS: Median and 5-year survival were 20 months and 25% for the Nonaggressive group, >96 months and 72% for the Resection/Ablation group, and 50 months and 50% for the TACE group. The survival for the Resection/Ablation and the TACE groups was significantly better (P < 0.05) when compared with the Nonaggressive group. Patients with more than 50% liver involvement had a poor outcome (P < 0.001). CONCLUSIONS: These data suggest that aggressive management of neuroendocrine hepatic metastases does improve survival, that chemoembolization increases the patient population eligible for this strategy, and that patients with more than 50% liver involvement may not benefit from an aggressive approach.  相似文献   
89.

Background/Purpose

The aim of this study was to analyze the outcome of giant omphalocele repaired in the neonatal period.

Methods

Twelve consecutive (1997-2004) neonates with giant omphalocele (defect >6 cm with liver herniation) were reviewed. A silo of Prolene mesh (Ethicon) was attached to the fascia and the defect was closed without opening the amniotic sac after sequential reduction. In 2 neonates with ruptured omphalocele a plastic sheet was inserted below the mesh. Data are reported as median and range.

Results

Gestational age was 38 weeks (range, 32-40 weeks) and birth weight was 2.9 kg (range, 1.0-3.1 kg). The final closure was achieved at 26 days (range, 16-62 days). Three neonates (25%) died before final closure (causes: ruptured omphalocele, lung hypoplasia, cardiac anomalies, and intestinal failure). In the 9 surviving neonates, mechanical ventilation was required for 8 days (range, 2-20 days), hospital stay was 42 days (range, 23-73 days), and full enteral feeding was achieved on day 12 (range, 4-53 days). Complications included wound infection in 5 neonates and midgut volvulus in 1. Prophylactic Ladd's procedure was performed laparoscopically at a later stage in 4 children. At laparoscopy, intraperitoneal adhesions were minimal and the central liver did not preclude the operation. The 9 survivors are all well after 46 months (range, 12-67 months).

Conclusions

Giant omphalocele can be safely repaired in the neonatal period without opening the amniotic sac. Intestinal malrotation should be excluded and Ladd's procedure can be performed laparoscopically at a later stage.  相似文献   
90.
Purpose: To develop and preliminarily evaluate a Social Difficulties Inventory (SDI) for use in oncology practice. Methods: Item generation from patients (n=96), staff (n=49) and the literature. Questions constructed and pre-tested (n=42) resulting in a 22-item questionnaire. Psychometric evaluation (n=271) assessed frequency of endorsement, factor structure, summated scales and construct validity followed by randomisation to criterion validity or test-retest arms. Results: Items met preset frequency of endorsement criteria. Factor analysis revealed a four-factor structure, three clearly definable, (1) Physical ability, (2) Providing for the family and (3) Contact with others, explaining 45.8% variance. Summated scales developed from these demonstrated good reliability (Cronbachs alpha > 0.7) and were used to test and confirmed construct validity. Several comparators from the Life Events and Difficulties Schedule (LEDS) and CAncer Rehabilitation Evaluation System Short Form (CARES-SF) tested criterion validity and majority agreements were moderate to good. Test–retest reliability was good with most kappa values > 0.6. One item was eliminated resulting in a 21-item questionnaire. Conclusion: The SDI is relevant and easy to understand. Initial psychometric evaluation was encouraging. Ongoing work to evaluate the clinical meaning and utility of the instrument and to examine the relationships between SDI scores and clinical outcomes will provide guidance about its usefulness as an assessment tool in routine oncology practice.Presented in part at the British Cancer Research Meeting (poster presentation) 2001 and at the World Congress of Psycho-Oncology (poster presentation) 2003.  相似文献   
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