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61.
We report a case of para-adrenal angiofollicular lymph node hyperplasia (Castleman's disease) of the hyaline-vascular type. The mass could not be differentiated from an adrenal tumor by ultrasonography and computed axial tomography (CT). However, magnetic resonance imaging (MRI) suggested the possibility of an extra-adrenal origin of the mass. The intensity of the mass by MRI was homogeneous and of a higher intensity in the T2-weighted image than in the T1-weighted image, a finding similar to lymphadenopathy, lymphatic tumorous mass or metastatic tumor of the lymph node. Ultrasonography, CT and MRI may not be useful in characterizing Castleman's disease, but MRI was useful to distinguish asymptomatic para-adrenal masses from those of adrenal origin.  相似文献   
62.
To investigate the role of glucose in regulating glucose transporters in pancreatic beta-cells, we studied the hamster clonal beta-cell line HIT-T15, which retains responsiveness to glucose. Northern blot analysis demonstrates that GLUT2 and GLUT1 mRNA are abundant in HIT cells. After a 24-h culture with various concentrations of glucose (0-22.2 mM [0-400 mg/dl]), the GLUT2 mRNA level in HIT cells increased by 40% at 22.2 mM (400 mg/dl) glucose compared with 11.1 mM (200 mg/dl) without a change in mRNA stability. It also decreased proportionally to the reduction of glucose concentration. Glucose deprivation resulted in a decrease of GLUT2 mRNA to an almost undetectable level, with a marked increase in the degradation rate of mRNA. In contrast, the GLUT1 mRNA was not affected by glucose. We show that glucose uptake is highest in HIT cells incubated at 2.8-5.5 mM (50-99 mg/dl) glucose for 24 h, and that levels in cells cultured at 0 mM (0 mg/dl) and 22.2 mM (400 mg/dl) glucose decrease to approximately 20% of the maximum level. This decrease is consistent with the effects of glucose on glucose-stimulated insulin secretion in HIT cells. Our results indicate that glucose is involved in regulating GLUT2 mRNA and glucose uptake activity and that the glucose responsiveness of the insulin secretion correlates with the glucose-induced change in glucose uptake activity in HIT cells.  相似文献   
63.
The present study examined the relationship between number of steps and body mass index (BMI) among male workers in the metropolitan area. The number of subjects were 310 (aged 30-59) and they were studied for seven consecutive days. The number of steps was measured by a pedometer. Energy expenditure was assessed by the activity record method. Energy intake was assessed by a food frequency questionnaire. Height and body weight were examined by a self-administered questionnaire. BMI of 81 subjects (26.1%) was greater than 25 kg/m2. The number of steps was 10,682 +/- 4,365 on working days, and 7,135 +/- 4,536 on holidays. Average energy expenditure in seven days was 2,259 +/- 378 kcal/d. The physical activity level (PAL) was 1.5 +/- 0.1. There was a significant correlation between BMI and the number of steps in a working day (r=-0.188, p<0.01). In addition, there were significant correlations between PAL and daily steps on working days (r=0.301, p<0.001), and on holidays (r=0.296, p<0.001). Subjects were divided into four groups according to the median number of steps on working days and energy intake (I; > or =9,894 steps, <1,901 kcal, II; > or =9,894 steps, > or =1,901 kcal, III; <9,894 steps, <1,901 kcal, IV; <9,894 steps, > or =1,901 kcal). BMI of Group IV (24.7 kg/m2) was significantly higher than that of the other Groups. Group III had the highest proportion of subjects (15.7%) with lifestyle related diseases.  相似文献   
64.
OBJECTIVE: Our treatment strategy for pulmonary atresia with ventricular septal defect (VSD) and major aortopulmonary collateral arteries is a staged repair that comprises the first complete unifocalization (UF) with 'unification' of intrapulmonary arteries and then the definitive repair. The purpose of this study is to evaluate the outcome of our staged repair strategy with complete UF and to determine the results of our current management strategy. METHODS: From 1982 to 2004, 113 consecutive patients were treated with staged repair at our institute. We evaluated the risk of definitive repair failure or death in the 3 years after definitive repair using logistic regression. Furthermore, we compared the early group (patients who underwent UF before December 1995) and the late group (patients who underwent UF after January 1996). RESULTS: The mean follow-up interval was 8.8 years (0.8 months to 23.3 years), and Kaplan-Meier-estimated overall survival rates after first UF were 80.9, 73.8, and 69.9% at 5, 10, and 15 years, respectively. Survival in patients with an absent central pulmonary artery (PA) was significantly lower than in those with a central PA (p<0.05), and the factor that was significantly associated with definitive repair failure or death in the 3 years after definitive repair was central PA morphology (p<0.05). Higher mean PA pressure after UF was detected in patients with hypoplastic central PA, compared with those without hypoplastic PA (30.9 mmHg vs 23.3 mmHg, p<0.05). In the late group, age (in years) at first UF (3.9 vs 8.4, p<0.01), second UF (4.3 vs 9.2, p<0.01), and definitive repair (5.8 vs 9.1, p<0.01) was significantly younger than in early group, and the survival rate after first UF in the late group was 96.2 and 91.3% at 3 and 7 years, respectively. Systolic right ventricular pressure and the pressure ratio between the right and the left ventricles after definitive repair in the late group were significantly lower than in the early group (53.6 mmHg vs 75.0 mmHg, p<0.01; 61.7% vs 75.9%, p<0.05). CONCLUSIONS: Hypoplastic central PA was a significant risk factor in this disease. The overall survival was improved by our current management strategy. Improved RV pressure after definitive repair appears to affect the long-term outcome.  相似文献   
65.
We present here a rare case of left-side catamenial pneumothorax, in which endometrial tissue pleura was found on the visceral pleura histologically. A chest roentogenogram confirmed the left pneumothorax, but did not reveal bullae or any associated anomalies, in a 41-year-old woman with three documented episodes of left-side pneumothorax occurring every menstruation. Video-assisted thoracoscopic surgery revealed not only tiny holes in the diaphragm, but also a scattered small brown spots on the visceral pleura. Histological examination of the lung sections revealed the existence of endometrial tissue on the visceral pleura with disrupted pleural elastic fibers. Our case suggests that cyclic erosion of the visceral pleura by the implanted endometrial tissue caused air leakage from the lung, in addition to the most accepted concept that air is aspirated into the thoracic cavity via the abdomen through the acquired fenestration of the diaphragm.  相似文献   
66.
This study compares neuropsychological functioning in a Japanese schizophrenia spectrum disorder group and a group of healthy Japanese volunteers. Participants were 37 patients diagnosed with schizophrenia, 28 schizotypal patients, and 99 psychiatrically-normal volunteers. A wide range of cognitive measures were examined. All participants completed a Japanese version of a neuropsychological battery assessing executive function, working memory, processing speed, language, verbal memory, and spatial organization. Comparisons of neuropsychological function demonstrated similarities and differences between patients diagnosed with schizotypal disorder and those diagnosed with schizophrenia. Impairments in verbal memory, language, and processing speed were common to both patient groups and may represent a vulnerability to schizophrenia. Impairments in aspects of working memory, spatial organization and executive function were preferentially observed in schizophrenia and may be features of the overt manifestation of psychosis. Possible differences in the contributions of prefrontal and temporo-limbic structures provide direction for further studies.  相似文献   
67.
A prototype electronic radial scan ultrasound endoscope has been developed by Olympus (Tokyo, Japan) for endoscopic ultrasound (EUS) study. The ultrasound view‐angle of this model is 360° vertical to the scope. Though the diameter of the scanner and the shaft of the scope is bigger than those of the present mechanical radial scan model, clinical manipulation of the new scope is the same as that of the present model. Image quality of the ultrasound picture demonstrated by the electronic radial model was as clear as those provided by the mechanical radial scan model. Ultrasound penetration was better and satisfactory because of less echoic reduction compared to the mechanical radial model. The newly developed electronic radial model can be evaluated as an ultrasound endoscope for the next generation. The advantage of this system is to facilitate the clinical use of color Doppler function and tissue harmonic imaging, and this system can be operated by the same monitor unit as a convex model of ultrasound endoscope.  相似文献   
68.
In our previous study, we demonstrated that high-dose 60Co irradiation was able to prevent rejection of canine tracheal allografts. To determine the maximum possible length of these grafts, in the present study we attempted to transplant five-ring and ten-ring tracheal allografts in two groups of five dogs each. Either five or ten rings were excised from donor tracheas and irradiated with 100,000 cGy of 60Co. The irradiated tracheal grafts were transplanted to replace either five- or ten-ring sections of the mediastinal tracheas removed from the recipient dogs. The grafts were covered with omental pedicles and no immunosuppressants were used. Graft incorporation was achieved in four of the five dogs in the five-ring group, and three of these dogs survived for more than 700 days. However, four of the five animals in the ten-ring group died from tracheostenosis accompanied by ischemia within 3 weeks. These findings demonstrate the impossibility of performing ten-ring tracheal allotransplantation using irradiated grafts, even with omentopexy.  相似文献   
69.
Abstract: Two autopsied female sibling cases of sudanophilic leukodystrophy are reported. Case A and case B were the second and third of seven siblings, and a sister and a brother died from severe progressive neurological disease with similar symptoms. Consanguineous marriages were noted in the family of both cases through the past three generations. Case A gradually developed intellectual deterioration and tetraplegia at the age of 29, progressed to akinetic mutism within one year and thereafter survived for 14 years. Neuropathologically, a severe atrophy and degeneration were noted in the white matter of the whole cerebrum, sparing the subcortical U-fibers. Myelin and axons were severely damaged with peripheral astrocytic gliosis. Case B developed similar clinical symptoms at the age of 20 and survived for 7 years in the state of akinetic mutism. Similar postmortem findings as those of case A were found in the white matter of the cerebrum with formation of sudanophilic breakdown products and with thick fibrillary gliosis. The pyramidal tract was completely degenerated. There was no accumulation of abnormal lipid in the brains of both cases.  相似文献   
70.
Background Stressful psychological stimuli produce an increase in renal sympathetic nerve activity (RSNA) and a decrease in renal blood flow. Very few direct analyses of the relationship between RSNA and renal blood flow during the application of psychological stimuli have been conducted by recording these 2 measurements simultaneously in the same individual animals. Methods We simultaneously measured RSNA and renal blood flow as a Doppler shift in conscious, unrestrained, spontaneously hypertensive rats. The rats were stressed by directing a continuous air jet at their faces for 20 seconds. Results Air-jet stimulus increased RSNA 81%±15% (mean±standard error of the mean, n=10), mean arterial pressure (21±3 mm Hg), and renal vascular resistance (37%±6%), and decreased renal blood flow (−15%±2%). The percentage change in RSNA correlated positively with the change in mean arterial pressure (r=0.934,P<0.001) and percentage change in renal vascular resistance (r=0.912), and negatively with the percentage change in renal blood flow (r=−0.804). The denervation of renal nerves prevented renal blood flow from decreasing in response to air-jet stress. Conclusions A reduction in renal blood flow in response to short-term air-jet stress is elicited mainly by neural mechanisms in spontaneously hypertensive rats. Enhancement of RSNA by air-jet stimulus exerts a potent constricting effect on the renal vascular bed, resulting in a reduction in renal blood flow.  相似文献   
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