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1.

Background  

Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure.  相似文献   
2.
1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage.  相似文献   
3.
After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation.  相似文献   
4.
5.
Pietro Rubegni  MD    Sara Poggiali  MD    Aldo Cuccia  MD    Maurizio Biagioli  MD    Michele Fimiani  MD 《Dermatologic surgery》2004,30(12P2):1539-1542
Background. Striated palmoplantar keratoderma or Brunauer-Fohs-Siemens syndrome is a very rare, focal, nonepidermolytic palmoplantar keratoderma with autosomal inheritance. Unlike other palmoplantar keratodermas, no association with visceral or skin cancer has ever been reported.
Objective. We report a case of malignant melanoma arising in the hyperkeratotic lesions on the right heel of a patient with striated palmoplantar keratoderma. The lesion was completely excised; our patient also underwent sentinel lymph node biopsy and then was treated with high-dose interferon adjuvant therapy.
Methods. Sentinel lymph node biopsy incision was made in elliptical fashion, long enough to harvest a full-thickness skin graft to cover the wide local excision defect. The skin graft was defatted by sharp dissection. Several perforations were made in graft and it was secured in place with sutures and bolster dressing.
Results. At follow-up, the grafted skin showed hyperkeratotic changes but no local or systemic signs of the disease was observed.
Conclusion. The association between striated palmoplantar keratoderma and acral melanoma is discussed.  相似文献   
6.
7.
S100A1 is a calcium-binding protein, which has been recently found in renal cell neoplasms. We evaluated the diagnostic utility of immunohistochemical detection of S100A1 in 164 renal cell neoplasms. Forty-one clear cell, 32 papillary, and 51 chromophobe renal cell carcinomas, and 40 oncocytomas, 164 samples of normal renal parenchyma adjacent to the tumors and 13 fetal kidneys were analyzed. The levels of S100A1 mRNA detected by quantitative RT-PCR analysis of frozen tissues from seven clear cell, five papillary, and six chromophobe renal cell carcinomas, four oncocytomas, and nine samples of normal renal tissues adjacent to neoplasms were compared with the immunohistochemical detection of protein expression. Clear cell and papillary renal cell carcinomas showed positive reactions for S100A1 in 30 out of 41 tumors (73%) and in 30 out of 32 (94%) tumors, respectively. Thirty-seven renal oncocytomas out of 40 (93%) were positive for S100A1, whereas 48 of 51 (94%) chromophobe renal cell carcinomas were negative. S100A1 protein was detected in all samples of unaffected and fetal kidneys. S100A1 mRNA was detected by RT-PCR in all normal kidneys and renal cell neoplasms, although at very different levels. Statistical analyses comparing the different expression of S100A1 in clear cell and chromophobe renal cell carcinomas observed by immunohistochemical and RT-PCR methods showed significant values (P<0.001), such as when comparing by both techniques the different levels of S100A1 expression in chromophobe renal cell carcinomas and oncocytomas (P<0.001). Our study shows that S100A1 protein is expressed in oncocytomas, clear cell and papillary renal cell carcinomas but not in chromophobe renal cell carcinomas. Its immunodetection is potentially useful for the differential diagnosis between chromophobe renal cell carcinoma and oncocytoma. Further, S100A1 protein expression is constantly detected in the normal parenchyma of the adult and fetal kidney.  相似文献   
8.
N-Nitrosodi-n-butylamine (NDBA), the NADPH generating system and various concentrations of butylated hydroxyanisole (BHA) added to rat hepatic S9 fractions resulted in a significant drop (30-50%) in N-nitrosobutyl(4-hydroxybutyl)amine (NBHBA) formation and a consequent rise in the amount of substrate recovered unchanged. When NBHBA and NAD+ were incubated with BHA and S9 fractions, the amount of N-nitrosobutyl(3-carboxypropyl)amine (NBCPA) was decreased by 20-40%, and the amount of unmetabolized NBHBA increased.  相似文献   
9.
10.
The urinary excretion of polyamines was evaluated before, during and after radiotherapy in 16 patients with advanced squamous cell carcinoma of the uterine cervix (stage IIb or IIIb) and in 7 cases with pelvic recurrence after surgery for various types of carcinoma. The concentration of spermidine was significantly higher in the patients with primary tumors than in those with recurrent tumors. After the first radiation fractions putrescine increased in the patients with primary tumors whereas it decreased in patients with recurrent tumors. The values tended to return to baseline levels with time following treatment initiation. Polyamine increased markedly during treatment in patients who remained disease-free for at least 5 years but not in the patients with progressive disease or relapse. The results suggest a different polyamine metabolism and a different response to radiotherapy of recurrent tumors compared to primary tumors. The increase of urinary polyamines, but not the baseline values, seemed to be correlated to the response after radiotherapy.  相似文献   
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