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81.
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   
82.
83.
A successful case of Norwood operation for a 5-day-old infant with hypoplastic left heart syndrome is reported. Norwood procedure and central shunting with a 4 mm PTFE tube was performed. Cerebral and coronary artery were perfused independently during reconstruction of aorta in order to shorten the time of circulatory arrest. Post operative UCG documented un-obstructive systemic output from the right ventricle, well regulated pulmonary arterial blood flow and widely patent interatrial communication. This baby was discharged the hospital 66 days after surgery. He has been clinically well for six month after the operation.  相似文献   
84.
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   
85.
OBJECTIVE: To minimize the neurological complications following cardiovascular surgery, it is essential to prevent an occurrence of cerebrovascular embolism and to detect and solve cerebral malperfusion without delay in the operating theater. Although we have introduced near-infrared spectroscopy (NIRS) monitoring for the purpose of detecting cerebral malperfusion, no criterion has been available. We searched for this criterion by examining the relationship of sustained drop in the regional oxygen saturation (rSO2) of the frontal lobes to the occurrence of neurological events. METHODS: The 59 consecutive patients undergoing aortic surgery with selective cerebral perfusion (SCP) were examined. The rSO2 was monitored throughout the surgery and the durations of drops in rSO2 to below 55% and those below 60% were determined for each patient. The durations of rSO2 drop and other surgery-related parameters were compared between the patients in whom neurological events occurred and those without such events. RESULTS: A total of 16 cases (27.1%) presented with neurological events. Newly developed cerebral infarction was documented in 6 of these 16 cases. Operation time and the durations for which rSO2 dropped were significantly longer for the 16 patients with neurological events than for the 43 patients without events (Op time: 546.8 versus 448.1 min, P=0.0064; rSO2 below 60%: 141.2 versus 49.8 min, P=0.0032; rSO2 below 55%: 66.6 versus 10.6 min, P=0.0011), while there was no significant difference in age, bypass time, aortic clamping time, SCP time, and circulatory arrest time between the two groups. In the 3 patients with infarcts suggestive to hypoperfusion, sustained decrease in rSO2 was observed, while it was not significant in the remaining 3 patients with infarcts suggestive to embolism. Among the 53 patients without infarction, transient neurological events occurred more frequently in patients with sustained drop in rSO2 below 55% for over 5 min (44.4% versus 5.7%, P=0.0014). CONCLUSIONS: A sustained drop in rSO2 during aortic surgery is closely related to the occurrence of neurological events following surgery. We recommend that recovery of drop in rSO2 below 55% should be addressed without delay. However, use of NIRS is limited for detecting embolic events or hypoperfusion in the basilar region.  相似文献   
86.
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   
87.
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   
88.
We report the first case of early-onset Parkinson's disease (EOP) with the PTEN-induced kinase 1 (PINK1) gene deletion in 62 years old Japanese female. The symptoms were started with unstable gait at the age 38. Parkinsonian symptoms became apparent in 45 years old. L-Dopa was markedly effective on her parkinsonian symptoms. However, equinovarus foot induced by L-Dopa intake appeared three months prior to the admission. On admission, she presented with mild cognitive impairment, severe depression, marked retropulsion, resting tremor in the left upper limb and mild hyperreflexia in the four limbs. Rigidity was not present. Mutational analysis revealed homozygous deletion from exon 6 to 8 in the PINK1 gene. An ethnic diversity in PINK1 mutation is suggested.  相似文献   
89.
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   
90.
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