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991.
This report describes the use of side-to-end anastomosis in a colostomy for an acute malignant large-bowel obstruction. A 59-year-old man presented with a colonic obstruction due to advanced descending colon cancer. The preoperative imaging studies revealed a complete obstruction of the descending colon at the site of the splenic flexure, a remarkably dilated transverse colon, and no other metastatic lesions. Side-to-end anastomosis was performed with the colostomy because of the high comorbidity associated with such cases. When the patient’s general condition improved, a stoma closure was performed under local anesthesia. In conclusion, a side-to-end anastomosis with a colostomy (STEC procedure) was found to be a simple, useful, and cost-effective technique for an acute malignant large-bowel obstruction, particularly in a high-risk patient.  相似文献   
992.
Introduction  We have accumulated over 170 patients since 1995 who underwent laparoscopic partial liver resection, laparoscopic left lateral sectionectomy, and laparoscopy-assisted hepatectomy. Bleeding control, which is a basic element of liver resection, needs to be better managed by methods suitable for safer laparoscopic liver resection. The aim of this study was to standardize the basic skills and to establish safer techniques for laparoscopic liver surgery in order to perform safe laparoscopic donor hepatectomy. Materials and methods  We analyzed initial results from the viewpoint of operative techniques of laparoscopic liver resection in our series. Laparoscopic liver resections have been successfully performed by the application of automatic suturing devices and the radiofrequency method. Results  We have performed 105 laparoscopic partial liver resections, 26 laparoscopic left lateral sectionectomies, and 45 laparoscopy-assisted major hepatectomies. A total of 176 patients underwent minimally invasive liver resections. Conclusion  For safer laparoscopic liver resection, efficient bleeding control techniques, such as radiofrequency pre-coagulation and the liver hanging maneuver, are needed during parenchymal transection of the liver. Laparoscopy-assisted donor hepatectomy can be safely performed without increasing operative risks with mini-laparotomy.  相似文献   
993.
Background and aim  A retrospective analysis was performed on 32 patients with histologically confirmed xanthogranulomatous cholecystitis (XGC) and 21 patients with gallbladder carcinoma who underwent surgical treatment between 1998 and 2007. Methods  All patients underwent preoperative CT scanning. The CT features analyzed were: the presence of intramural hypoattenuated nodules or bands, mucosal line, the patterns of wall thickening and enhancement, and the presence of stones in the gallbladder. The variables of the CT findings with XGC were analyzed using multivariate logistic regression analysis. Results  Intramural hypoattenuated nodules were observed in 21 patients (65%) with XGC, but in only six patients (29%) with gallbladder carcinoma (< 0.01). The mucosal line was observed in 27 patients (84%) with XGC and in only four patients (19%) with gallbladder carcinoma (< 0.0001). Gallstones were noted in 24 patients (75%) with XGC and five patients (24%) with gallbladder carcinoma (< 0.001). There was no significant difference in the pattern of gallbladder wall thickening (diffuse or focal) and the presence of changes outside the gallbladder. Multivariate logistic regression analysis revealed from the CT features that the enhanced continuous mucosal line (= 0.0013) and the presence of gallstones (= 0.0072) were independently correlated with XGC. Conclusion  CT features of the enhanced continuous mucosal line in a thickened gallbladder wall, together with gallstones in a patient with chronic gallbladder disease, are highly suggestive of XGC. Accurate diagnosis of XGC may therefore indicate the need to select a less aggressive surgical approach.  相似文献   
994.
Background  The double tract (DT) method was compared with the Roux-en-Y (R-Y) method to identify the optimal reconstruction procedure after total gastrectomy for patients with gastric cancer. The DT reconstruction is as simple as the R-Y, and it can be safely performed even after total gastrectomy. However, these have been no studies evaluating the usefulness of DT reconstruction in comparison to R-Y reconstruction. Methods  A group of 44 patients with gastric cancer were intraoperatively randomized for R-Y (n = 23) or DT reconstruction (n = 21) after total gastrectomy (TG). Body weight, food intake, nutritional conditions, and quality of life (QOL) were determined at 3 and 12 months after the operation. This study is registered with ClinicalTrials.gov, no. NCT00746161. Results  Food intake significantly decreased soon after the operation. No differences were observed between the DT and R-Y groups. The body weight decreased throughout the ensuing period (P < 0.05) and thereafter gradually recovered. However, no differences were observed between the two groups. Among the nutritional laboratory parameters, serum prealbumin, retinol-binding protein, total cholesterol, and triglyceride were decreased soon after the operation. The changes of those parameters were not substantially different between the two groups. The postoperative QOL was evaluated, and no differences were observed between those groups. Conclusions  There were no particular advantages in the DT method after TG in comparison to the simple R-Y method in terms of body weight, QOL, and nutritional conditions, suggesting that the DT method might not be recommended after TG for patients with gastric cancer.  相似文献   
995.

Background

To investigate biomaterials seeking for their possible use for aneurysm treatment, in vivo screening tests using a number of potential materials are required. However, there is no established animal model that is suitable for such purpose. Some models require special preparation of tested materials for transcatheter delivery and others are inappropriate in view of their cost-effectiveness. The purpose of this study is to establish an animal model that overcomes these limitations and help us select potential materials before the preclinical evaluation.

Methods

Bilateral CCAs in a rabbit were surgically ligated, and a 2-cm segment of either a bare platinum coil or a polymeric coil (a platinum coil coated with PLGA 10/90) was implanted into each blind-ended arterial segment (n = 26). They were harvested at day 1, 7, 10, 14, or 30, respectively. Angiographic and histologic evaluations as well as quantitative analysis on the development of the organized thrombus were performed.

Results

One day after the implantation, both platinum and PLGA coils were surrounded by immature thrombus that was induced by blood flow stagnation in the arterial segment. At day 7, minimal thrombus organization was observed around both types of materials. At postimplantation days 10 and 14, fibrocellular responses, the early findings of the thrombus organization process, were observed in both material groups. Such histologic findings were more prominent in the PLGA coil group as compared to the platinum coil group (day 10, P = .051; day 14, P = .011). Well-organized thrombus was observed in both material groups at day 30 without showing statistical difference (P = .12).

Conclusion

Given the cost-effectiveness, the simple material preparation process, and its feasible histologic evaluation methods, this new animal model can be useful in screening other potential biomaterials for the development of new coil devices.  相似文献   
996.
Reported herein is a case of medulloblastoma with myogenic differentiation in a 3-year-old girl who died 1 year after appearance of clinical signs. Magnetic resonance imaging indicated a mass lesion in the cerebellar vermis. She underwent total resection of the tumor, followed by chemotherapy and radiotherapy in the brain and spinal cord. The resected specimen mainly consisted of densely packed cells with round-to-oval highly chromatic nuclei surrounded by scanty cytoplasm and focally of long spindle-shaped cells with elongated nuclei and eosinophilic cytoplasm showing discernible cross-striations. Immunohistochemistry indicated partial expression of synaptophysin in the former area and focal expression of desmin in the latter area. The diagnosis was medulloblastoma with myogenic differentiation, also known as medullomyoblastoma. Autopsy indicated disseminated proliferation of immature neuroglial cells with highly chromatic nuclei and scanty cytoplasm showing partial expression of synaptophysin, neurofilaments, and GFAP, and focal proliferation of round-to-oval immature cells showing immunoreactivity of myoglobin. The tumor cells had large nuclei, frequent mitoses, apoptoses, nuclear molding, and cell wrapping, indicating moderate anaplasia. Their Ki-67 labeling index was 54%. In addition, some tumor cells had double immunopositivity for synaptophysin or neurofilament and myoglobin, suggesting that the neuroectodermal cells may undergo differentiation into rhabdomyoblasts.  相似文献   
997.
We describe a strategy for the in vitro engineering of enamel tissue using a novel technique for culturing enamel organ epithelial (EOE) cells isolated from the enamel organ using 3T3-J2 cells as a feeder layer. These subcultured EOE cells retain the capacity to produce enamel structures over a period of extended culture. In brief, enamel organs from 6-month-old porcine third molars were dissociated into single cells and subcultured on 3T3-J2 feeder cell layers. These subcultured EOE cells were then seeded onto a collagen sponge in combination with primary dental pulp cells isolated at an early stage of crown formation, and these constructs were transplanted into athymic rats. After 4 weeks, complex enamel-dentin structures were detected in the implants. These results show that our culture technique maintained ameloblast lineage cells that were able to produce enamel in vivo. This novel subculture technique provides an important tool for tooth tissue engineering.  相似文献   
998.
999.
1000.
Background  The present study aimed to elucidate the relationship between microvessel count (MVC) according to CD34 expression and prognosis in intrahepatic cholangiocarcinoma (ICC) patients who underwent hepatectomy based on our preliminary study. Methods  Relationships between MVC and clinicopathological factors were examined in 37 ICC patients. CD34 expression was analyzed using immunohistochemical methods. Results  Median MVC for ICC patients was 140/mm2, which was applied as a cutoff value. Lower MVC was significantly associated with larger tumor size, periductal infiltrating type, and advanced Japanese tumor–node–metastasis stage (p < 0.05). Univariate survival analysis identified higher carcinoembryonic antigen level, periductal infiltrating type, poor histological differentiation, and lower MVC as significantly associated with lower 5-year survival rates. The 5-year survival rate in the higher-MVC group was significantly greater than that in the lower-MVC group (44% vs. 7%, p = 0.048). According to Cox multivariate survival analysis, only periductal infiltrating type on macroscopic examination was identified as a significant independent risk factor for poor survival after hepatectomy (risk ratio 4.8; p = 0.006), not MVC (1.1; p = 0.82). Conclusion  Tumor MVC might offer a useful prognostic marker of ICC patient survival after hepatectomy and further investigation in a larger series is warranted.  相似文献   
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