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61.
62.
The carcinogenic activity of endogenously synthesized N-nitrosobis(2-hydroxypropyl)amine(BHP) was investigated in male Wistar rats administered bis(2-hydroxypropyl)amine(BHPA) mixed in powder diet at a concentration of 1%, and sodiumnitrite (SN) dissolved in distilled water at concentrationsof 0.15 and 0.3%, for 94 weeks. Urinary excretion of BHP wasdetected in rats given 1% BHPA and 0.3% SN but not in the groupsreceiving either of these precursors alone. Nasal cavity, lung,esophagus, liver and urinary bladder tumors were found in animalstreated with combinations of 1% BHPA and 0.15 or 0.3% SN, suggestingthat the target organs of the endogenously synthesized BHP aresimilar to those affected when the carcinogen is administeredexogenously. The incidences of nasal cavity and lung tumorsreached 74 and 58% in rats given 1% BHPA and 0.3% SN, respectively.Tumors at sites other than target organs were only found atlevels similar to those previously reported for spontaneoustumors in male Wistars. The present results clearly indicatedthe tumor inducibility of a nhrosatable amine, BHA, throughan endogenous nitrosation by feeding to rats in conjunctionwith nitrite, and provide further suggestive evidence that endogenousnitrosations of environmental nitrosatable amines can be a potentialrisk factor in human cancer development.  相似文献   
63.
In 268 of the 1,115 patients (24.0%) with gastric cancer who underwent a curative resection in our clinics, the tumor was located in the middle third of the stomach. The clinicopathological features and prognosis of these patients were divided into two groups, according to site of the tumor: anterior wall (n = 58) vs. other sites (n = 210). Clinicopathological factors did not differ between the two groups. The survival time for patients with a tumor in the anterior group was shorter than that for patients with a tumor in other areas (P < 0.05). The five-year survival rate was 79.3% for patients with an anterior tumor and 91.9% for those with a tumor at a different site. A multivariate analysis indicated lymph node metastasis, serosal invasion, and anterior wall location to be independent prognostic factors indicative of a poor prognosis when the tumor was located in the middle third of the stomach. For such patients, close follow-up is needed to detect possible recurrences. © 1993 Wiley-Liss, Inc.  相似文献   
64.
The purpose of the present study was to elucidate the cardiac structure and function in patients who have metabolic syndrome but no history of cardiovascular disease by analyzing echocardiographic findings. Echocardiographic examination was performed to screen for cardiovascular disease in 135 patients who were in their sixties. Patients were divided into metabolic syndrome (n=65, age: 65+/-2.7 years) and non-metabolic syndrome (n=70, age: 66+/-2.5 years) groups based on the criteria for metabolic syndrome proposed by the Japanese Society of Hypertension and seven other societies in 2005. The left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. The relative wall thickness, LV mass index, and LV ejection fraction (LVEF) were calculated. LV diastolic function was assessed by the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial filling (A velocity), and the ratio of E to A (E/A) was assessed by the transmitral flow. The Tei index, which reflects both LV diastolic and systolic function, was also calculated. There were no differences in relative wall thickness, LV mass index, or LVEF between the two groups. However, both the EIA and Tei index were significantly different between the metabolic syndrome (0.66+/-0.14 and 0.36+/-0.07, respectively) and non-metabolic syndrome (0.88+/-0.25 and 0.29+/-0.09) groups (p<0.001). These results indicate that patients with metabolic syndrome can have cardiac diastolic dysfunction even if they have neither LV hypertrophy nor systolic dysfunction.  相似文献   
65.
Recently, a self‐expandable metallic stent has been recognized for treatment of malignant duodenal stenosis. But the complications by stenting are important problems even now. In the present study, we report our new method of duodenal stenting by using of double‐balloon enteroscopy considered safe and effective.  相似文献   
66.
We encountered a rare case of unilateral internal carotid arterial defect complicated with anterior communicating aneurysm and subclavian artery aneurysm. The patient was a 56-year-old man in whom cerebral angiography and 3D-CTA revealed defects in the right internal carotid artery and the right carotid canal, and an unruptured aneurysm in the anterior communicating artery. In addition, the patient was also found to have an unruptured aneurysm in the right subclavian artery. As both the aneurysms were considered to have a high risk of rupture and such subclavian aneurysms were likely to cause an embolism, radical surgery was performed for each aneurysm. The postoperative course was uneventful, and the patient was discharged without ambulatory limitations. Although the defect in the internal carotid artery is a relatively rare vascular deformity, the incidence of cerebral aneurysm is about 30% in such cases due to the marked hemodynamic stress involved. On the other hand, there have been only two previous case reports of internal carotid arterial defect complicated with a subclavian aneurysm. Moreover, there have been no previous reports of internal carotid arterial defect complicated with both an intracranial aneurysm and a subclavian aneurysm, as observed in the present case. Thus, this case was very rare and is reported here.  相似文献   
67.
68.
Benazepril (CGS 14824A HCl) is a new prodrug type angiotensin converting enzyme (ACE) inhibitor. The active form is considered to be benazeprilat, a diacid hydrolyzed compound. Benazepril and benazeprilat inhibited the contraction induced by exposure with angiotensin I, not angiotensin II, in the isolated rabbit aorta. The ACE inhibiting activity of benazeprilat was 1000 times more potent than that of benazepril in this experiment. Benazepril as well as benazeprilat and captopril exerted little influence on norepinephrine, serotonin and high K(+)-induced contraction or bradykinin-induced relaxation in isolated blood vessel preparations, thus angiotensin II synthesis inhibition seemed to be the main cause for its vasodilation. Benazepril, unlike benazeprilat or captopril showed considerable influence on prostaglandin (PG)-induced responses at higher concentrations. The vasocontraction induced by PGF2 alpha was competitively antagonized at 10(-5)-10(-4) mol/l, while vascular responses induced by PGE1, PGE2 or PGI2 was inhibited at 3 x 10(-4) mol/l of benazepril. Although these influences on PGs might not contribute much to its vasodilatory mechanism, the action seemed interesting in relation to cough induction, a known side effect of ACE inhibitors in the market. Benazepril has two asymmetric carbon atoms, thus four optical isomers are possible, SS (benazepril), SR (CGP 14'829A), RS (CGP 42'454A), RR (CGP 42'456A). The SS configuration was the most potent for antagonizing angiotensin I-induced vasocontraction, which seemed to be the best fitted for the ACE molecule.  相似文献   
69.
We investigated the effects of age and naftidrofuryl oxalate (Naftidrofuryl), a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus using quantitative autoradiography. [3H]Quinuclidinyl benzilate (QNB), [3H]cyclohexyl-adenosine (CHA), [3H]MK-801, and [3H]muscimol were used to label muscarinic acetylcholine, adenosine A1, N-methyl-d-aspartate (NMDA), and γ-aminobutyric acid-A (GABAA) receptors, respectively. [3H]PN200-110 labeled L-type Ca2+ channels. [3H]Forskolin, [3H]cyclic adenosine monophosphate (cAMP), [3H]phorbol 12,13-dibutyrate (PDBu), and [3H]inositol 1,4,5-triphosphate (IP3) were used to label adenylate cyclase, cAMP-dependent protein kinase, protein kinase C (PKC), and IP3 receptors, respectively. Approximately 20% reductions in [3H]QNB, [3H]forskolin, and [3H]PDBu binding were observed in the hippocampus of 9-month-old gerbils in comparison with 5-week-old gerbils. Treatment with Naftidrofuryl (10 mg/kg, i.p., once a day for 7 days) ameliorated these reductions. No changes were found in [3H]CHA, [3H]MK-801, [3H]muscimol, [3H]PN200-110, [3H]cAMP, and [3H]IP3 binding. The results suggest that Naftidrofuryl may have beneficial effects on the age-related alterations in signal transmission and transduction systems in the brain. Because the acetylcholine system, adenylate cyclase, and PKC are considered to be involved in learning and memory processes, the result may have clinical implications.  相似文献   
70.
We report herein the case of a 75-year-old man who developed anal canal metastasis from squamous cell carcinoma of the lung. Initially, he underwent a right middle and lower lobectomy combined with left atrial wall resection under cardiopulmonary bypass. He presented 3 months later with an anal polyp which had prolapsed and bled, for which he underwent a transanal polypectomy. Histologically, the polyp was classified as squamous cell carcinoma and considered to be a metastasis from the primary lung cancer. He is presently well with no signs of recurrence 9 months after his initial operation. To our knowledge, there has been no other case of anal metastasis from lung cancer ever reported.  相似文献   
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