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61.
The efficacy of orthotopic liver transplantation (OLT) for hepatocellular carcinoma (HCC) associated with hepatitis C virus (HCV) is not well defined. This study examines the variables that may determine the outcome of OLT for HCC in HCV patients. From 1990 to 1999, 463 OLTs were performed for HCV cirrhosis. Of these patients, 67 with concurrent HCC were included in the study. Univariate and multivariate analyses considered the following variables: gender, pTNM stage, tumor size, number of nodules, vascular invasion, incidental tumors, adjuvant chemotherapy, preoperative chemoembolization, alpha-fetoprotein (AFP) tumor marker, lobar distribution, and histological grade. Overall OLT survival of HCV patients diagnosed with concomitant HCC was significantly lower when compared to patients who underwent OLT for HCV alone at 1, 3, and 5 years (75%, 71%, and 55% versus 84%, 76%, and 75%, respectively; P < 0.01). Overall survival of patients with stage I HCC was significantly better than patients with stage II, III, or IV (P < .05). Eleven of 67 patients developed tumor recurrence. Sites of recurrence included transplanted liver (5), lung (5), and bone (1). Twenty-four of 67 patients (36%) died during the follow-up time. Causes of deaths included recurrent HCC in 8 of 24 patients (12%) and recurrent HCV in 3 of 24 patients (4.5%), whereas 13 (19.5%) patients died from causes that were unrelated to HCV or HCC. Both univariate and multivariate analysis demonstrated that pTNM status (I versus II, III, and IV; P < .05) was a reliable prognostic indicator for patient survival. Presence of vascular invasion (P = .0001) and advanced pTNM staging (P = .038) increased risk of recurrence. Multivariate analysis showed that pretransplant chemoembolization and adjuvant chemotherapy reduced risk of death after OLT in HCC recipients. In conclusion, this study demonstrates the effectiveness of OLT for patients with HCC in a large cohort of chronic HCV patients. Advanced tumor stage, and particularly vascular invasion, are poor prognostic indicators for tumor recurrence. Early pTNM stage, adjuvant chemotherapy, and preoperative chemoembolization were associated with positive outcomes for patients who underwent OLT for concomitant HCV and HCC.  相似文献   
62.
BACKGROUND: Laparoscopic cholecystectomy (LC) has replaced open cholecystectomy for the treatment of gallbladder disease. Despite the well-accepted success of LC in chronic cholecystitis, the efficacy of this technique has been subject to some debate in acute cholecystitis (AC). This study was designed to evaluate our institution's experience with LC for AC and chronic symptomatic calculous cholecystitis (CC), based on complication and conversion rates to open surgery. PATIENTS AND METHODS: The records of 1158 patients with LC from September 1991 to December 2001 were analyzed. The parameters of age, gender, early and late complication rates, and conversion rates from LC to open cholecystectomy were compared in patients with AC and CC. RESULTS: During the study period, LC was performed in 1158 patients. Of these, 162 patients had AC (group 1) and 996 patients had CC (group 2). The conversion rates were 4.3% (7/162) in group 1 and 2.4% (24/996) in group 2. The complication rates were not significantly different (5.6% in group 1, 5.1% in group 2, P > 0.05). Difficulty in dissection around Calot's triangle and obscure anatomy were the main reasons for conversion to conventional open surgery. The mortality rate was 1.2% in group 1 and 0.01% in group 2. CONCLUSION: LC appears to be a reliable, safe, and effective treatment modality for AC and CC. The surgical approach should be performed carefully because of the spectrum of potential hazards of the laparoscopic procedure. Conversion and complication rates are similar in both AC and CC groups, and improve as surgeons gain experience.  相似文献   
63.
The purpose of this study was to investigate the sinus node artery in the sheep heart to establish adequate baseline information for use in cardiovascular research, and to compare this information with similar data for man. The coronary arteries were exposed by using injection-corrosion casting technique in 60 sheep hearts. Polyester and diluted sulfuric acid were used. When the corrosion was completed, the specimens were photographed. The sinus node artery was single in 59 specimens, and double in one specimen. The artery originated from the right coronary artery (in 42 specimens), left coronary artery (in 16 specimens), and right aortic sinus (in 1 specimen). In the majority of specimens, sinus node artery corresponded to the right superior (anterior) atrial artery. Pericaval termination was common. Mean measurements about the sinus node artery were tabulated. According to the present study, we can state that the sinus node artery in sheep heart is similar to that of humans. Because of the importance of animal research, we suggest that experimental surgical studies of the sinus node artery should be performed on the sheep heart.  相似文献   
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Purpose  

Adjuvant chemotherapy is currently offered, as standard, after curative resection for patients with rectal cancer who receive neoadjuvant chemoradiation (NCRT). We postulate that adjuvant chemotherapy adds minimal oncologic benefit for patients who undergo total mesorectal excision who are node-negative after neoadjuvant chemoradiation.  相似文献   
67.
68.

Context

Primary vesicoureteral reflux (VUR) is a common congenital urinary tract abnormality in children. There is considerable controversy regarding its management. Preservation of kidney function is the main goal of treatment, which necessitates identification of patients requiring early intervention.

Objective

To present a management approach for VUR based on early risk assessment.

Evidence acquisition

A literature search was performed and the data reviewed. From selected papers, data were extracted and analyzed with a focus on risk stratification. The authors recognize that there are limited high-level data on which to base unequivocal recommendations, necessitating a revisiting of this topic in the years to come.

Evidence synthesis

There is no consensus on the optimal management of VUR or on its diagnostic procedures, treatment options, or most effective timing of treatment. By defining risk factors (family history, gender, laterality, age at presentation, presenting symptoms, VUR grade, duplication, and other voiding dysfunctions), early stratification should allow identification of patients at high potential risk of renal scarring and urinary tract infections (UTIs). Imaging is the basis for diagnosis and further management. Standard imaging tests comprise renal and bladder ultrasonography, voiding cystourethrography, and nuclear renal scanning. There is a well-documented link with lower urinary tract dysfunction (LUTD); patients with LUTD and febrile UTI are likely to present with VUR. Diagnosis can be confirmed through a video urodynamic study combined with a urodynamic investigation. Early screening of the siblings and offspring of reflux patients seems indicated.Conservative therapy includes watchful waiting, intermittent or continuous antibiotic prophylaxis, and bladder rehabilitation in patients with LUTD. The goal of the conservative approach is prevention of febrile UTI, since VUR will not damage the kidney when it is free of infection. Interventional therapies include injection of bulking agents and ureteral reimplantation. Reimplantation can be performed using a number of different surgical approaches, with a recent focus on minimally invasive techniques.

Conclusions

While it is important to avoid overtreatment, finding a balance between cases with clinically insignificant VUR and cases that require immediate intervention should be the guiding principle in the management of children presenting with VUR.  相似文献   
69.
Organ transplantation offers children in acute or chronic severe organ failure similar opportunities to adults. However, while the number who might benefit is relatively low, significantly fewer cadaveric donors exist for any given child compared with an adult. Incompatible organ size and relatively low donation rates mean that despite living parental donation and innovations to reduce donated organ size, children die before organs become available. The severity of the UK situation is compounded by restrictions on paediatric living donation, uncertainties over the application of brain death criteria, and ethical concerns about the use of donation after circulatory death. The UK Department of Health's Organ Donation Task Force suggested the means by which the adult donor pool might be increased, recommending that outstanding ethical and legal issues be resolved, but made no specific recommendations about children.  相似文献   
70.
Micturating cystourethrogram (MCUG) is an imaging technique indicated in the diagnosis and follow-up of many diseases. We investigated the reliability and the efficacy of midazolam and chloral hydrate in sedation and anxiolysis during micturating cystourethrogram. Fifty-three children of similar ages (39 girls, 14 boys, mean age of 5.8±3.5 years) were randomized to midazolam (n=17), chloral hydrate (n=18) and control groups (n=18). Oral midazolam 0.6 mg/kg or chloral hydrate 25 mg/kg or saline were administered to the study groups 15–30 min prior to the urinary catheterization. Brietkopf and Buttner, Frankl and Houpt scales and Spielbergers State Anxiety Inventory and parents impressions were used to assess the level of sedation and anxiety. The Brietkopf and Buttner classification of emotional status and Houpt behavior rating scale demonstrated a significantly better emotional status and sedation in the midazolam group when compared to controls (P=0.01 and P=0.018, respectively). The catheterization was described as a more unpleasant and distressing event by the parents of the control and the chloral hydrate groups when compared to the parents of the midazolam group (P<0.05). Bladder capacity and frequency of detection of residual urine were not statistically different between the three study groups (P>0.05). Vital signs did not change significantly in any child. Sedation with midazolam does not have adverse effects on the results of micturating cystourethrogram, while it reduces the discomfort in children undergoing this radiological technique.This paper was presented as an oral poster at the Thirteenth Congress of the International Pediatric Nephrology Association.  相似文献   
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