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81.
Background. Breast-conserving therapy has been widely accepted as a standard treatment for early breast cancer both in Western countries and in Japan. In Western countries, many studies have investigated the risk factors for local recurrence after breast-conserving therapy (BCT), but few such studies have been done in Japan. Methods. To determine the risk factors for local recurrence in 399 breast cancer patients (stage I and II, n = 396; stage III, n = 3) who had undergone BCT with or without postoperative radiation therapy, we evaluated their clinicopathological features by univariate and multivariate analyses. The patients were treated at Osaka National Hospital between February 1988 and December 1997. Results. Univariate analysis showed that a young age (≤45 years; P = 0.0005) was a significant risk factor for local recurrence, while radiation therapy (P = 0.0058) and adjuvant endocrine therapy (P = 0.0041) significantly reduced the risk of local recurrence. In patients with BCT, without radiation therapy a positive surgical margin significantly increased the risk of local recurrence (P = 0.0470). Multivariate analysis showed that a young age (P = 0.0285) was a significant independent risk factor for local recurrence, while radiation therapy (P = 0.0457) significantly decreased recurrence. In patients with a negative surgical margin, radiation therapy (P = 0.0158) and adjuvant endocrine therapy (P = 0.0421) significantly reduced the relative risk of local recurrence, to 0.160 and 0.366, respectively. In patients with a positive surgical margin, radiation therapy marginally significantly (P = 0.0756) reduced the relative risk of local recurrence, to 0.181, and adjuvant endocrine therapy significantly (P = 0.0119) reduced the risk, to 0.076. Conclusions. Young age and lack of radiation therapy or adjuvant endocrine therapy were risk factors for local recurrence in breast cancer patients treated with breast-conserving therapy, with surgical margin status also being a possible risk factor. Received: November 9, 1998 / Accepted: March 11, 1999  相似文献   
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83.
Twin pregnancy consisting of a complete hydatidiform mole (CHM) along with a live co-existing fetus is a rare entity and difficult to diagnose. A 37-year-old Japanese woman demonstrated a living fetus, a placenta and a multicystic mass within one gestational sac on ultrasound at 10 weeks. Termination of the pregnancy was performed, and the specimen was classified as partial mole by macro- and microscopic findings. The karyotype of the molar tissue was 46XX. DNA polymorphism analysis demonstrated that fetal DNA showed bi-parental origin while molar DNA showed paternal origin only. Thus, this case was erroneously classified by ultrasonography, macroscopic and pathologic findings, then correctly diagnosed as a twin pregnancy with a CHM and co-existing normal twin fetus by DNA polymorphism analysis. Immunohistochemistry of p57(KIP2), the paternally imprinted and maternally expressed gene, supported the genetic diagnosis. This case suggested that conventional diagnostic methods were inadequate for accurate diagnosis of CHM with a co-existing fetus. DNA polymorphism analysis should be requested for the diagnosis of hydatidiform mole, especially in cases where it is difficult to discriminate between partial hydatidiform mole and CHM with a co-existing fetus.  相似文献   
84.
Vascular endothelial growth factor (VEGF) and its receptors play an important role in tumor progression; however, there is no report regarding this factor in uterine sarcoma. Thirty-nine patients with uterine sarcoma, 14 carcinosarcomas, 4 endometrial stromal sarcomas, and 21 leiomyosarcomas, were studied. By immunohistochemical staining, VEGF was not detected in normal uterine smooth muscle, but VEGF receptor-1 (flt-1) and VEGF receptor-2 (flk-1) were observed in 14 and 4 of 14 normal smooth muscles, respectively. Of 39 sarcomas, 25 expressed VEGF, and 38 and 34 sarcomas expressed flt-1 and flk-1 at various intensities, respectively. The staining intensity of VEGF, flt-1, and flk-1 was significantly higher in sarcoma than in normal uterine smooth muscle, but that of phospho-flt-1 (p-flt-1) was significantly lower in sarcoma than in normal uterine smooth muscle. When sarcomas were divided into two groups according to staining intensity, a significant difference in survival curves was observed in only p-flt-1 of leiomyosarcoma (P= 0.008), and in all sarcomas, a lower survival curve was also observed in the high staining intensity group than in the low staining intensity group, although there was no significant difference (P= 0.102). In conclusion, VEGF and its receptors are suggested to be involved in progression of uterine sarcoma, but only the p-flt-1 level significantly affected the survival of leiomyosarcoma patients.  相似文献   
85.
86.
Evidence for existence of polyol pathway in cultured rat mesangial cells   总被引:4,自引:0,他引:4  
The accumulation of polyols has been previously found in renal glomeruli isolated from streptozocin-induced diabetic (STZ-D) rats, although the intraglomerular polyol pathway has not been exactly localized. Because we have previously observed mesangial cell dysfunction in STZ-D rats, we examined whether the polyol pathway exists in mesangial cells as a possible candidate of the cause of cellular dysfunction. The activities of two polyol pathway enzymes, aldose reductase and sorbitol dehydrogenase, were clearly detected in the crude homogenate of cultured mesangial cells at higher levels than those of whole glomeruli when DL-glyceraldehyde or D-fructose was used as substrate. When cells were incubated in medium containing 55 mM glucose or galactose, a large amount of sorbitol or galactitol was accumulated intracellularly. The accumulation of polyols was effectively blocked by an aldose reductase inhibitor, ICI 128436. These results suggest that the polyol pathway exists in mesangial cells of rat glomeruli and may play a role in the development of mesangial cell dysfunction found in STZ-D rats.  相似文献   
87.
88.
The "reduced in osteosclerosis" transporter (Roct), which shows decreased expression in the osteosclerosis (oc) mutant mouse, has high homology with rat and human organic anion transporter 3 (OAT3). However, its transport properties and involvement in bone turnover are poorly understood. Here, we examined Roct-mediated transport using a Xenopus laevis oocyte expression system. Roct-expressing oocytes exhibited uptake of [(3)H]estrone sulfate, [(3)H]p-aminohippuric acid, [(3)H]benzylpenicillin, [(3)H]estradiol 17beta-glucronide, [(3)H]indoxyl sulfate, [(14)C]indomethacin, [(3)H]homovanillic acid, [(3)H]cimetidine, [(14)C]glutarate, [(14)C]salicylic acid, and [(3)H]methotrexate. Furthermore, the uptake of [(3)H]benzylpenicillin by Roct coexpressed with Na(+)-dicarboxylate cotransporter was trans-stimulated by glutarate preloading, and [(3)H]estrone sulfate uptake showed a similar tendency, suggesting that Roct is a dicarboxylate exchanger. [(3)H]Benzylpenicillin uptake by Roct was inhibited by OAT3 substrates and inhibitors, and by sulfate or glucuronide conjugates, and compounds involved in bone turnover. Roct mRNA is expressed abundantly in the kidney and was also detected in the brain, choroid plexus, and eye. Immunohistochemical analysis revealed that Roct is localized in brain capillary endothelial cells. These results indicate that the transport properties and tissue distribution of Roct are similar to those of OAT3, suggesting that Roct functions as mouse OAT3. Because Roct is expressed in the kidney and at the blood-brain barrier, it may play a role in the excretion of substrates such as conjugates and bone turnover factors.  相似文献   
89.
The thiazolidinedione compounds are well known hypoglycemic agents via increasing insulin-sensitivity. Herein, we provide the possibility that thiazolidinedione compounds could be useful for renal dysfunction through mechanism dependent or independent of its insulin-sensitizing action. In type 2 diabetes, troglitazone could reduce urinary albumin-creatinine ratio compared to metformin. Furthermore, we have shown that troglitazone was able to prevent diabetic glomerular dysfunction through inhibition of diacylglycerol-protein kinase C-extracellular signal-regulated kinase pathway in type 1 diabetic rats. Thus, thiazolidinediones might be effective agents for treating insulin-resistant diabetes as well as diabetes-induced kidney disease.  相似文献   
90.
OBJECTIVE: The purpose of this study was to evaluate the efficacy of fidarestat, a novel aldose reductase (AR) inhibitor, in a double-blind placebo controlled study in patients with type 1 and type 2 diabetes and associated peripheral neuropathy. RESEARCH DESIGN AND METHODS: A total of 279 patients with diabetic neuropathy were treated with placebo or fidarestat at a daily dose of 1 mg for 52 weeks. The efficacy evaluation was based on change in electrophysiological measurements of median and tibial motor nerve conduction velocity, F-wave minimum latency, F-wave conduction velocity (FCV), and median sensory nerve conduction velocity (forearm and distal), as well as an assessment of subjective symptoms. RESULTS: Over the course of the study, five of the eight electrophysiological measures assessed showed significant improvement from baseline in the fidarestat-treated group, whereas no measure showed significant deterioration. In contrast, in the placebo group, no electrophysiological measure was improved, and one measure significantly deteriorated (i.e., median nerve FCV). At the study conclusion, the fidarestat-treated group was significantly improved compared with the placebo group in two electrophysiological measures (i.e., median nerve FCV and minimal latency). Subjective symptoms (including numbness, spontaneous pain, sensation of rigidity, paresthesia in the sole upon walking, heaviness in the foot, and hypesthesia) benefited from fidarestat treatment, and all were significantly improved in the treated versus placebo group at the study conclusion. At the dose used, fidarestat was well tolerated, with an adverse event profile that did not significantly differ from that seen in the placebo group. CONCLUSIONS: The effects of fidarestat-treatment on nerve conduction and the subjective symptoms of diabetic neuropathy provide evidence that this treatment alters the progression of diabetic neuropathy.  相似文献   
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