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101.
A system in which the retinal tissues of noninbred Wistar rats were used in combination with autoradiography was developed for measurement of DNA repair synthesis in ganglion cells of the central nervous system. Retinal tissues in short-term organ culture were treated with various carcinogens plus tritiated thymidine ([methyl-3H]dThd) or were irradiated with UV light and then treated with [methyl-3H]dThd. Preliminary study with retinal tissues from rats at various ages revealed no age-associated changes in the levels of unscheduled DNA synthesis in ganglion cells.  相似文献   
102.
The binding of benzo(a)pyrene (BP) to DNA in the presence ofliver microsomal preparations from 3-methylcholanthrene-treatedrats was increased 28.5% (P < 0.001) by addition of UDP-glucuronicacid to the incubation mixture at a 100 µM concentrationof BP. However this increase was not observed at lower concentrationsof BP. Analysis of DNA-hydrolysates by column chromatographyon Sephadex LH-20 indicated that this increase was due to greaterbinding of benzo(a)pyrene-7, 8-dihydrodiol-9, 10-epoxide. Theamount of bound adducts derived from 9-hydroxybenzo(a)pyrene(9-OH BP) was not significantly affected by UDP-glucuronic acid.Addition of UDP-glucuronic acid to incubation mixtures containingmicrosomes from untreated rat liver caused only a slight increasein total binding. These findings suggest that UDP-glucuronyltransferase may be involved in the activation of BP.  相似文献   
103.
Thickening of the root of the superior mesenteric artery (SMA) was studied by using preoperative sonography in 23 patients with pancreatic cancer and in 10 healthy control subjects. Of the 23 with cancer, 11 had neoplastic involvement of the SMA and 12 did not. Prominent thickening of the area around the SMA with (six patients) or without (five patients) decreased echogenicity compared with the adjacent retropancreatic connective tissue was observed in patients with involvement of the SMA, a finding called the "cuff sign." Mean thickness of the periarterial area in the cancer patients with and without involvement of the SMA and in control subjects were 8.5 mm, 4.0 mm, and 2.9 mm, respectively. With an upper limit of normal of 7.0 mm for the thickness of the SMA, the sensitivity, specificity, and overall accuracy of this sign in the evaluation of involvement of the SMA were 91%, 100%, and 96%, respectively. Decreased echogenicity of the periarterial area was not observed in patients without involvement of the SMA or in control subjects. Our results show that sonographic evidence of periarterial thickening of the root of the SMA (cuff sign), especially with decreased echogenicity, is a reliable finding of tumor infiltration of the SMA in patients with pancreatic carcinoma.  相似文献   
104.
A 26-year-old female patient complicated with reflux nephropathy and pheochromocytoma is reported. We could not find either intrinsic or extrinsic factor of urinary tract obstruction. The open bilateral renal biopsy was performed at the time of resection of the tumor. The renal biopsy specimen demonstrated minor glomerular change, severe tubular "thyroid-like" appearance and cast formation in the obvious reflux side. Otherwise focal glomerular sclerosis (FGS) lesion was found in less reflux side. In reflux nephropathy, FGS lesion is reported as main cause of progression, but mechanism of FGS lesion is unknown. This case which has both vesicoureteral reflux the high plasma nor-epinephrine concentration was considered to be important to emphasize circulative factor in the pathogenesis of FGS like lesion.  相似文献   
105.
BACKGROUND: Prostatic intraepithelial neoplasia (PIN), an intraluminar proliferation of epithelial cells in ducts and acini, is divided into high-grade (HGPIN) and low-grade (LGPIN), based on morphologies. HGPIN is considered to be a putative precursor of prostatic adenocarcinoma (PCA). Information on PIN has been limited in Japan, because PIN had not been regarded as a precursor lesion for PCA. METHODS: In this study, extent and zonal distribution of PIN together with its relationship with PCA were examined in totally embedded radical prostatectomy specimens obtained from 70 patients with PCA. Fifty-three patients received androgen deprivation therapy (castrated) and remaining 17 did not (noncastrated). RESULTS: Frequency of HGPIN in noncastrated cases (76%) was much higher than that in castrated cases (26%) (P < 0.001). LGPIN showed the same tendency, but the difference was smaller. Difference in mean number of HGPIN in noncastrated and castrated cases (12.0 and 6.4, respectively) was more marked than in LGPIN (6.4 and 5.1, respectively). Reduction rate of mean size in HGPIN (26%) by the androgen deprivation therapy was larger than in LGPIN. When evaluated in noncastrated cases, the coexistence of PCA and HGPIN was found in 76% of cases in the nontransition and 53% in the transition zone. Close association of PCA and PIN (相似文献   
106.
The purpose of this study is to evaluate the influence of surgery for unruptured aneurysms on neuropsychological status and cerebral metabolism. We studied 21 patients with unruptured aneurysms treated with direct surgery accompanied by craniotomy, rather than by the endovascular method. Patients were evaluated before and after surgery, using the Wechsler adult intelligence scale revised (WAIS-R) and proton magnetic resonance spectroscopy which measured the ratio of N-acetyl-aspartate to creatine (NAA/Cr). Although the results of WAIS-R (total IQ, verbal IQ and performance IQ) was not significantly different after surgery in any of the patients, the total IQ of the patients with anterior communicating artery aneurysms (AcoA) showed a significant decline compared with patients with other aneurysms after surgery. Five of eight AcoA patients showed a specific reduction in verbal IQ, suggesting deterioration of recent memory. The NAA/Cr remained within the normal range and was not significantly different before and after surgery. However, the NAA/Cr in the white matter of the frontal lobe of AcoA patients showed a significant reduction compared with that of non-AcoA patients. All three elderly patients older than 70 showed a reduction in NAA/Cr of more than one standard deviation from normal subjects in their frontal or parietal lobes. These results indicated that operation for unruptured aneurysms is reliable and well established but they also show that careful consideration should be given to possible deterioration in neuropsychological status and cerebral metabolism after operation in AcoA and elderly patients.  相似文献   
107.
Donor safety is the first consideration in living related liver transplantation. Left hemihepatectomy including the middle hepatic vein is a reasonable donor procedure for obtaining a large graft for living related liver transplantation. This procedure, however, needs to be modified in donors with hepatic venous variation. While carrying out donor hepatectomy, we encountered two cases showing a variant form of hepatic venous drainage comprising a thick middle hepatic vein draining segment 6 of the liver. This variation made it necessary to preserve the middle hepatic vein in the donor liver remnant. Failure to recognize such a variant would result in congestion in the remaining right liver of the donor. To guarantee donor safety, evaluation of the drainage area of the corresponding hepatic vein is a matter of great importance in donor hepatectomy.  相似文献   
108.
109.
BACKGROUND: The role of changes in peri-operative blood lactate levels in recipients of living-related liver transplants has not yet been clarified. METHODS: Forty-three recipients were included in this study. Blood lactate, plasma total bilirubin, aminotransferase, body temperature, and gastric mucosal PCO2 levels were measured at six time points during surgery: just before the initiation of surgery, just after dissection of the hepatic vasculature, at the end of the anhepatic phase, and 30, 60, and 120 min after reperfusion. We calculated the rate of lactate accumulation during the pre-anhepatic and anhepatic phases and the elimination rate during reperfusion (neohepatic phase), and examined the correlation between these results and the clinical findings. RESULTS: The rate of lactate elimination during the neohepatic phase was correlated with the ratio of graft weight to standard liver volume (P<0.0001). There was also a significant correlation between the rate of lactate accumulation during the pre-anhepatic phase and the preoperative total bilirubin levels (P=0.0008). CONCLUSIONS: Each pre-anhepatic, anhepatic, and neohepatic phase had a characteristic blood lactate profile. The graft size strongly affected lactate levels during the early neohepatic phase.  相似文献   
110.
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