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51.
The vasodilator effects of C-type natriuretic peptide (CNP) were investigated in isolated rat cerebral arterioles. CNP caused dose-dependent vasodilation, maximally by 10.0±2.2% at 10−6 M. The median effective concentration (EC50) was 5.2×10−10 M. In contrast, atrial natriuretic peptide and B-type natriuretic peptide, other members of the natriuretic peptide family, produced little or no vasodilation. Pretreatment with methylene blue (10−4 M) abolished CNP-induced vasodilation, whereas pretreatment with NG-monomethyl--arginine or indomethacin did not inhibit vasodilation. Thus, CNP is suggested to cause significant vasodilation in cerebral arterioles via a cyclic guanosine monophosphate-dependent mechanism. © 1997 Elsevier Science B.V. All rights reserved.  相似文献   
52.
A case-control study was conducted to examine factors relating to discontinuation of domiciliary care for the bedridden elderly in Shinagawa-ku, Tokyo. Cases were bedridden residents aged 65 years and over who had abandoned home care and applied for admission to live in a special nursing home for the aged between April and September in 1990 after being recipients of welfare allowances for disabled elderly. Controls were bedridden residents who continued to be given home care and matched to cases by sex, age and beginning month of the receiving of allowances. Among 50 cases and 94 controls interviewed, we obtained responses from 31 cases (62%) and 60 controls (64%). The main results were as follows: 1. During the home-care period, ADL (activities of daily living) of cases, especially walking ability, deteriorated more severely than in controls. Night delirium also appeared more frequently in cases. 2. The primary caregivers of cases were older than those of controls. Remarkable differences between cases and controls were observed in the family structure, the number of family members and the number of sub-caregivers. Cases tended to live alone or live with a spouse only, and with smaller number of family members and caregivers. 3. Case lived more frequently in houses with small numbers of rooms and without rooms of their own. 4. As regards utilization of domiciliary care services, cases used dispatch of home helpers more frequently and used day services less frequently.  相似文献   
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A review of data on 360 patients with esophageal squamous cell carcinoma who underwent esophageal resection revealed 14 cases (3.9%) and 16 lesions with synchronous gastric carcinomas. Among the 16 lesions, there were 14 (87.5%) early gastric carcinomas and two advanced carcinomas. Of the 14 early gastric carcinomas, two were minute (less than 5 mm in the largest diameter) early gastric carcinomas and four small (6-10 mm in the largest diameter). These gastric carcinomas were in a relatively early stage. The six early gastric carcinomas were not detected preoperatively. However, a thorough observation of the gastric mucosa could not be done in four of those due to stenosis which had developed as a result of the esophageal carcinoma. Therefore, intraoperative gastric observation should be done in cases in which the findings of the preoperative endoscopic examination of the stomach are inadequate and the upper gastrointestinal series reveal certain gastric abnormalities.  相似文献   
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The heating performance of prototype variable power control units attached to two domestic microwave ovens, 500 W and 700 W, was investigated. The units employed the phase control method where rated voltage was obtained by switching AC supply at a particular angular position on the sinusoidal voltage. In order to create experimental conditions employed in a previous study, Sydney tap water (50 mL) was heated at a 10% power level in the 500 W oven. Water boiled at 10 min in both experiments. However, the precision and control of the heating was greatly improved with addition of the control unit. A disinfecting solution (50 mL) and a tissue fixative (10 mL) were included for experiments with the 700 W oven. A power level of only 1% was sufficient to maintain the temperature of the fixative at low temperatures (30-40 degrees C) where many biological reactions occur. The present results indicate that microwave heating power can be controlled by the variable power control method. This will make temperature control possible through the provision of an electronic feedback loop which links a thermocouple with the power control unit.  相似文献   
57.
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported. A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate angiography, a CT scan, and magnetic resonance imaging is necessary.  相似文献   
58.
40 specimens consisting of 27 carcinomas, 9 lymphomas, 2 thymomas, 1 sarcoma and 1 neurinoma were studied by immunoperoxidase technique to demonstrate a cell proliferation-associated antigen defined by proliferating cells (PC) antibody. Though PC antibody expression did not seem to correlate well with histologic grading of carcinomas, positivity to this was consistently more intense in carcinomas than in normal epithelia. Correlation with histologic grading of lymphomas was more significant: the high grade types, e.g. ATL, exhibited greater positivity than intermediate grade types, e.g. diffuse medium lymphoma and certainly much more than low grade types, e.g. follicular lymphomas. These data were compared to another proliferation-associated antigen, the transferrin receptor.  相似文献   
59.
Systemic acute rhinosinusitis therapy consists mostly of antibiotic treatment because pathogens play a major role. Amoxicillin is the drug of choice for treatment of acute rhinosinusitis, with second- and third- generation cephalosporins, azythromycin, clarithromycin, and telithromycin as possible options, especially in the case of allergy to amoxicillin. If the clinical course suggests that an anaerobic pathogen is more likely, clindamycin or metronidazole can be considered in combination with a broad-spectrum drug. In antimicrobial treatment of chronic sinusitis there is no consensus on treatment length, organism coverage, or which antibiotics are most effective because the bacteriology is variable with polymicrobial anaerobic and aerobic organisms present. Adjuvant therapies need to be proven by additional studies. Chronic rhinosinusitis is heterogeneous and treatment should vary according to the causative factor involved. Short courses of systemic steroids have been found very useful to decrease mucosal swelling and inflammation in chronic rhinosinusitis. However, no randomized controlled studies have been performed to validate their efficacy in children. A variety of other agents are used in the treatment of chronic rhinosinusitis including antihistamines, decongestants, and leukotriene modifiers. To date, there is no good evidence from randomized controlled studies to support the use of any of these agents in the treatment of this disease in either children or adults.  相似文献   
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