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51.
Paraffin-embedded primary tumor specimens from 48 patients with breast cancer were examined for DNA ploidy, S-phase fraction (SPF), and concanavalin A (Con A) reactivity. The results were correlated with clinicopathological prognostic factors, including patients' age and menopausal status, stage of disease, nuclear grade, and size of the primary tumor. There were no associations among ploidy, SPF, Con A reactivity, and menopausal status, stage of disease, or size of the primary tumor. However, among patients who were 50 years or older, 81 % had diploid tumors and 73% had good reactivity (3+ or better staining score) with Con A. In contrast, among patients who were younger than 50 years, 45% had diploid tumors (P < 0.05) and 21% had good Con A reactivity (P < 0.05). Seven of 19 (37%) poorly differentiated tumors and 7 of 9 (78%) moderately differentiated tumors had good reactivity with Con A (P < 0.05). Reactivity of tumor cells with Con A in primary breast cancer tissues deserves further evaluation as a potential biomarker of prognosis. © 1994 Wiley-Liss, Inc.  相似文献   
52.
Recently, there has been many investigations on the relationship between leptin and obesity, which is the main health problem in developed countries. In some reports, it has been claimed that the adrenalectomy has lead to weight loss and thus prevented obesity induced in rodents in various ways. It has also been accepted that diet-induced obesity in animals is very similar to obesity in humans beings. In this study, obesity has been developed with high-calorie diet given for 8 weeks in Sprague-Dawley rats. Then, it has been investigated how leptin and some metabolic parameters change in blood samples obtained from rats 15 d after adrenalectomy. Leptin levels was determined with Radio Immun Assay (RIA, Linco Research Co) method. Our study showed that, there were statistically significant increases in leptin (p<0.001), glucose (p<0.05), triglyceride (p<0.01) levels in diet-induced obese rats (n=19) when compared with the findings of control rats, lean ones (n=16), (Tables 3, 4). Adrenalectomy led to decreased serum leptin (p<0.001) and triglyceride (p<0.01) levels both in the obese and lean rats (Table 5). As a conclusion, it could be claimed that the decrease in leptin levels may be attributed to reduced adipose tissue due to adrenalectomy. On the other hand, the decreases in glucose and triglyceride levels might be the consequence of reduced lipogenesis and impaired gluconeogenesis with the effect of adrenalectomy. It was concluded that adrenalectomy might prevent obesity by affecting leptin and intermediate metabolism.  相似文献   
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In this study, we investigated the effects of somatostatin analog RC-160 on the growth of the OV-1063 human epithelial ovarian cancer cell line in vitro. RC-160 inhibited cell proliferation, as measured by cell number, and [(3)H]thymidine incorporation into DNA at 10(-9)-10(-5) M. In OV-1063 cells, (125)I-labeled RC-160 was bound to one class of specific, saturable binding sites with high affinity (K(d) = 0.2 +/- 0.03 nM) and low capacity (5,500 binding sites per cell). (125)I-labeled RC-160 could be displaced by unlabeled RC-160. Ligand binding was dependent on time and temperature. Receptor internalization assay showed that the ligand-receptor complex was internalized at 37 degrees C, which indicates the presence of biologically active somatostatin receptors on OV-1063 cells. These results suggest that somatostatin analog RC-160 can suppress the growth of OV-1063 human epithelial ovarian cancer cells by a direct action and that the inhibitory effect of somatostatin analog is mediated through the high-affinity somatostatin receptors.  相似文献   
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Bilateral unusual coursed ovarian arteries were found in a 45-year-old female cadaver. The ovarian arteries arose from the abdominal aorta at a level inferior to the corpus of L1 vertebra bilaterally. The right ovarian artery was coursing behind the inferior vena cava. The left one was coursing between the left renal artery and vein upward to the level of the inferior part of the body of Th12 vertebra. At the level of Th12 vertebra, it turned caudally and proceeded downward between the anterior-inferior and posterior segmental renal veins. On both sides, ovarian arteries were on their normal routes below the L2 vertebra accompanying the ovarian veins. The variation determined by this study would reduce possible complications of nephrectomy operations that urologists, gynecologists and other related surgeons may encounter.  相似文献   
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BACKGROUND: The life expectancy of patients with chronic renal failure who are dependent on dialysis is very poor. This study was undertaken to determine time-related outcomes in dialysis patients requiring cardiac valve replacement. METHODS: From 1994 to 2001, 29 end-stage renal disease (ESRD) patients on hemodialysis (HD) program underwent 30 valve replacement operations: 29 received mechanical valves (97%), and one received bioprosthetic valves. The sites of valve replacement were 11 aortic (36.7%), 18 mitral (60%), and one both aortic and mitral (3.3%). Mean age was 42.46 +/- 14.26 years (range 17-75 years). Follow-up was completed in 28 patients (96.5%). RESULTS: Early postoperative mortality (in the first 30 days) was 3.4% (n = 1). The overall estimated Kaplan-Meier survival was 56.7% at 36 months, 46.7% at 60 months, and 43.3% at 96 months. HD program was discontinued for two patients after renal transplantation in the follow-up period. All patients, except the one with bioprosthesis, used warfarin sodium for anticoagulation and none of them had bleeding. One of the patients had a major cerebrovascular accident (CVA) and another one had a minor CVA at the follow-up (6.7%). CONCLUSIONS: Life quality is better and life expectancy is longer after valve replacement in ESRD patients who have valvular disease. Also, longer life expectancy increases the probability for finding donors for kidney transplantation.  相似文献   
59.
OBJECTIVE: Stricture formation is a late complication of caustic esophageal burn, which is a common problem in childhood. For this reason, this experimental study was designed to observe the possible effect of nitric oxide on healing and fibrosis formation in caustic esophageal burns. MATERIALS AND METHODS: The rats were divided into five groups. Group A (n=12) received sham burn and treatment with saline injection. Group B (n=34) received caustic burn. Rats in group C (n=31), were given water supplement with 10 g/L L-arginine that was started 24 h preoperatively and continued until postoperative day 4. In group D (n=21), S-methylisothiourea (SMT, specific inducible nitric oxide synthase (iNOS) inhibitor), was injected at a dose of 3 mg/kg i.p. at 30 min before caustic burn, and similar dose was reinjected immediately after caustic burn. SMT 6 mg/kg/day injections continued for 4 days long. In group E (n=22), Nomega-nitro-L-arginine (L-NNA, nonspecific nitric oxide synthase (NOS) inhibitor) was injected at a dose of 15 mg/kg i.p. at 30 min before caustic burn, and similar dose was reinjected immediately after caustic burn. L-NNA 30 mg/kg/day continues for 4 days. RESULTS: Dead rates were significantly higher in group E than in groups A-D. The mean hydroxyproline levels in esophageal tissue were significantly lower in groups A and B than in group D. Histopathologically, tissue damage scores in the esophageal tissue were higher in group D than in groups A-C. CONCLUSIONS: Inhibition of iNOS with SMT was impaired in wound healing due to caustic esophageal burn and provoked collagen accumulation at a later period. Those effects may due to inhibition of antioxidant, immunomodulatory and antifibrotic effects of NO.  相似文献   
60.
Foreign body asphyxiation in children   总被引:3,自引:0,他引:3  
Goren S  Gurkan F  Tirasci Y  Kaya Z  Acar K 《Indian pediatrics》2005,42(11):1131-1133
We aimed to investigate the frequency and epidemiological features of deaths due to foreign body asphyxiation (FBA) in childhood, over 1990-2003. Of the victims, 14 (63.6%) were male and 8 (36.4%) females. The mean age of the victims was 2.2 +/- 0.6 years. There were 20 (90.9%) children between 1 and 3 years, and two other cases at 2/12 and 5 years of ages. All aspirations had occurred at home. Eight (36.4%) of the victims were dead on arrival, 11 (50%) on intervention, and 3 (13.6%) after complications. Food material was the most commonly aspirated foreign body in 81.8% of the cases, nuts being the most common (50%). Food asphyxiation remains a common problem particularly in children between 1 and 3 years of age in our region. These fatal accidents can be prevented by parental education and early recognition and management of the situation.  相似文献   
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