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981.
The treatment strategies in patients with gastric cancer aged 80 years or older have not yet been well defined. We examined the incidence of postoperative complications and hospital mortality regarding the preoperative condition of such patients. A preoperative examination included evaluations of the cardiac, pulmonary, renal, and hepatic functions, the presence or absence of anemia, nutritional status, and blood sugar content. The incidence of postoperative complications and hospital mortality were then studied in relation to the number of preoperative abnormal parameters. The incidence of postoperative complications was 37.0%. The rate of hospital mortality was 11.1%. Among the patients with abnormalities in five or more items, the incidence of complications was 76.9% and the rate of hospital mortality was 23.1%. In the patients with an operative time of 4h or longer, the same incidence was 71.4%. Among the patients who underwent a curative resection, the 5-year survival rate was 92.3%. For elderly gastric cancer patients with abnormalities in five or more items during a preoperative examination and for those showing a poor level of daily life activity, a less invasive treatment modality should be planned. Patients with abnormalities of four or fewer items at a preoperative examination appear to be good candidates for curative resection.  相似文献   
982.
Two cases of an extremely rare cystic lymphoepithelial lesion of a lymph node associated with the pancreas are presented herein. The first patient was a 57-year-old woman with a serous cystoadenoma who underwent resection of the body and tail of pancreas, and the other patient was a 75-year-old woman with cancer of the papilla of Vater who underwent pylorus-preserving pancreatoduodenectomy. Both lesions were incidentally found during pathologic examination of lymph nodes from the peripancreatic region. Histologically, there were many scattered nests of the lymphoepithelial lesion in the lymphoid stroma, each of which was lined with stratified squamous epithelium. The pathological structure was found to resemble the lymphoepithelial lesion of the pancreas. Although the histogenesis is unknown, we hypothesize that the lesion might have arisen from squamous metaplasia of a benign epithelial inclusion such as the pancreatic duct of an ectopic pancreas in a peripancreatic lymph node. Therefore, a cystic lesion formed as a result of keratinization of the squamous epithelium with invasion into the pancreas could become a lymphoepithelial cyst of the pancreas.  相似文献   
983.
PurposeTo investigate the impact of the size and location of waterclefts (WC), which are one of several cataract subtypes, on visual function by optical simulation analysis.MethodsAn optical simulation software (CODE V) was used to develop a schematic eye model and several sizes of WC central and peripheral types that were located below the anterior and posterior subcapsules of the crystalline lens, and analyses of refraction, higher-order aberrations (HOA), and the modulation transfer function (MTF) were performed.ResultsAn increase in the WC size increased the refraction and HOA and decreased the MTF. The impact of the WC below the posterior subcapsule on the visual function was more enhanced than that below the anterior subcapsule. Large WC demonstrated a remarkable hyperopic shift in refractive power as well as an increase in HOA. The MTF decreased slightly with increasing WC size at a spatial frequency of 20 cycles/mm, and it decreased remarkably at 60 cycles/mm.ConclusionsThe impact on the visual function increased with increasing WC size. It was revealed that eyes with WC below the posterior subcapsule are more hyperopic than those with WC below the anterior subcapsule, and the former have a higher HOA and lower MTF than the latter.  相似文献   
984.
985.
The purpose of the present study was to evaluate the clinical outcome of peripheral stent placement after failed balloon angioplasty in patients with grafts who are on hemodialysis. We examined 30 Wallstents that were placed in 26 patients because balloon angioplasty failed or early restenosis (<3 months) occurred within 3 months. We retrospectively reviewed 267 consecutive balloon angioplasties performed in 71 patients with graft access between August 2000 and March 2007. Stent placements accounted for 30 (11.2%) of the 267 balloon angioplasties. The clinical success rate of stent placement was 93.3% (28 of 30 stent placements). The 3-, 6-, and 12-month primary patency rates were 73.3%, 39.3%, and 17.7%, respectively. The 1-, 2-, and 3-year secondary patency rates were 90.2%, 83.8%, and 83.8%, respectively. Primary patency was significantly prolonged by stent placement after early restenosis compared with previous balloon angioplasty alone (P = 0.0059). Primary patency after stent placement was significantly lower than after successful balloon angioplasty without indications for stent placement (P = 0.0279). Secondary patency rates did not significantly differ between stent placement and balloon angioplasty alone. The mean number of reinterventions required to maintain secondary patency after stent placement was significantly larger than that after balloon angioplasty alone (Mann–Whitney U test, P = 0.0419). We concluded that peripheral stent placement for graft access is effective for salvaging vascular access after failed balloon angioplasty and for prolonging patency in early restenosis after balloon angioplasty. However, reinterventions are required to maintain secondary patency after stent placement. Furthermore, peripheral stent placement for graft access cannot achieve the same primary patency as balloon angioplasty alone.  相似文献   
986.
We used metal wires and fibers to fabricate a composite knitted stent and then compare the mechanical characteristics of this stent with those of a pure metallic stent of the same construction in order to develop a stent that offers a comparable degree of expandability as metallic stents but can be used for highly curved lesions that cannot be treated using metallic stents. We fabricated two types of composite knitted stent (N–Z stents), using nitinol wire with a diameter of 0.12 mm and polypara-phenylene-benzobisoxazole (PBO) multifilament fiber (Zyron AS; Toyobo, Osaka, Japan). Stents were knitted into a cylindrical shape using the same textile pattern as a Strecker stent. Two loop lengths (L) of nitinol wire were used in the N–Z stents: L = 1.84 mm (N–Z stent L = 1.84) and L = 2.08 mm (N–Z stent L = 2.08). For the sake of comparison, we fabricated a metallic stent of nitinol using the same textile pattern (N–N stent L = 1.92). We applied a radial compression force diametrically to each stent and applied a bending force diametrically at the free end of a stent with one end fixed in order to evaluate the relationship between stent elasticity and load values. In addition, we macroscopically evaluated the generation of kinks when the stent was bent 180°. The radial compressive force when the stent diameter was reduced by 53% was 6.44 N in the case of N–Z stent L = 1.84, 6.14 N in the case of N–Z stent L = 2.08, and 4.96 N in the case of N–N stent L = 1.92 mm. The composite stent had a radial compressive force higher than that of a metallic stent. The restoring force to longitudinal direction at a 90° bending angle was 0.005 N for N–Z stent L = 1.84, 0.003 N for N–Z stent L = 2.08, and 0.034 N for N–N stent L = 1.92. The restoring force of the composite stent was significantly lower. Finally, the composite stent generated no definitive kinks at a bending angle of 180°, regardless of loop length. However, the N–N stent clearly produced kinks, causing blockage of the inner cavity. In conclusion, the use of a metal and fiber composite in the construction of a knitted stent ensures an expansion performance comparable to that of metallic stents, while providing better kink resistance.  相似文献   
987.
Breast cancer is common in women all over the world, and exploration of chemopreventive approaches to this cancer is very important. Nimesulide, a selective inhibitor of cyclooxygenase-2 (COX-2), is a good candidate as a chemopreventive agent with low toxicity. We examined its effects on mammary tumor development in female Sprague-Dawley rats induced with the environmental carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Rats at 7 weeks of age received intragastric intubations of PhIP (85 mg / kg body weight) 4 times weekly for 2 weeks and were maintained on control diet (high fat diet) or experimental diet (high fat diet supplemented with 400 ppm nimesulide) throughout the experiment. COX-2 protein was over-expressed in epithelial cancer cells and stromal cells of the PhIP-induced mammary carcinomas, but was weak or not apparent in normal mammary gland cells. The development of mammary carcinomas was clearly suppressed by administration of nimesulide. The carcinoma incidence was 51% as compared to 71% for the control diet group. The average multiplicity of carcinomas in the experimental diet group was 1.2 +/- 0.2 (P < 0.05), significantly smaller than the control diet group value (2.6 +/- 0. 5). The size of carcinomas was also clearly decreased; 1.1 +/- 0.4 cm(3) / rat in experimental diet group (P < 0.05), 4.1 +/- 1.3 cm(3) / rat in the control diet group. The results therefore provide evidence that the selective COX-2 inhibitor, nimesulide, possesses chemopreventive activity against PhIP-induced mammary carcinogenesis in rats.  相似文献   
988.
OBJECTIVE: This study was conducted to determine whether specific ultrasonographic findings in the prenatal period were associated with survival of children affected with trisomy 18. METHOD: Between October 1987 and July 2004, we collected 24 cases with trisomy 18. We investigated the relationship of prenatal ultrasonographic findings, gestational age at delivery, the Apgar score, the mode of delivery, and the neonatal treatment strategies, with survival time. RESULTS: 17 of the 24 neonates died within 1 month after birth (Group 1), 5 died within 12 months (Group 2), and 2 survived for more than 1 year (Group 3). Severe polyhydramnios was more frequent in group 1. In groups 2 and 3, the fluid in fetal stomach was visible in all cases. Severe cardiac anomalies were more frequent in group 1. In groups 2 and 3, all neonates were girl. CONCLUSION: Prenatal ultrasonographic findings associated with survival less than 1 month included severe polyhydramnios, absence of the fluid in the stomach, severe cardiac anomaly and male sex.  相似文献   
989.
990.
A 50-year-old woman was diagnosed as having stage IV breast cancer with bilateral supraclavicular lymph node metastasis resistant to CAF therapy. She received immunotherapy using autologous tumor lysate-pulsed dendritic cells (DCs). Four cycles of DC injection into the right supraclavicular lymph nodes resulted in regression of bilateral supraclavicular lymphogenous metastasis. Histological studies revealed an accumulation of CD45+ T lymphcytes in the regressive lymph nodes. This case suggests that immunotherapy with DCs may be a safe and promising approach for the treatment of advanced breast cancer. Received: July 27, 2000 / Accepted: January 9, 2001  相似文献   
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