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91.
The aim of this study was to evaluate breast parenchymal activity on scintimammography with bone-seeking agents and 99mTc-MIBI. Scintimammography was performed with bone-seeking agents in 61 patients and with 99mTc-MIBI in 33 patients. Activity in the breast parenchyma contralateral to the suspected lesion was visually assessed by two independent observers. Increased breast parenchymal activity was shown in 19 of 61 patients examined with bone-seeking agents, while it was demonstrated in only two of 33 patients examined with 99mTc-MIBI. Breast parenchymal activity of bone-seeking agents was higher in patients aged 50 years or younger than in those older than 50. Increased parenchymal activity of bone-seeking agents may disturb visualization of primary breast cancer especially in relatively young patients. Low parenchymal activity is suggested to be a favorable characteristic of 99mTc-MIBI as a scintimammographic agent.  相似文献   
92.
A questionnaire survey was carried out among 1041 students in secondary schools and colleges in Dar-es-Salaam, Tanzania to evaluate the relationship between HIV-risky sexual behaviour and anti-condom bias, as well as with AIDS-related information, knowledge, perceptions and attitudes. Self-reportedly, 54% of students (75% of the boys and 40% of the girls) were sexually active, 39% had a regular sexual partner and 13% had multiple partners in the previous year. The condom use rate was higher than previous reports. However, 30% of sexually active respondents did not always use condoms (Risk-1 behaviour) and 35% of those with multiple partners in the previous year did not always use condoms (Risk-2 behaviour). Multiple logistic regression analyses indicated that 'sex partner hates condom' had association with both Risk-1 behaviour (OR 2.47; 95% CI 1.58-3.85) and Risk-2 behaviour (OR 2.47; 95% CI 1.10-5.48). 'Use of condom prevents HIV infection' also had association with both Risk-1 behaviour (OR 2.09; 95% CI 1.19-3.67) and Risk-2 behaviour (OR 3.73; 95% CI 1.28-11.03). Students engaging in risky behaviour were aware of the risk, even though they failed to change their behaviour. Reasons for the AIDS epidemic among Tanzanian students and the importance of more effective AIDS education are also discussed.  相似文献   
93.
Factors associated with knee pain were investigated using 871 self-administered questionnaires (405 men and 466 women) from residents aged over 30 years in a rural area of Japan. The prevalence of knee pain increased with age, particularly in women over 50. It was significantly higher in women than in men. Body mass index (BMI) was significantly related to knee pain in women, though not in men. With reference to occupational factors, frequent heavy lifting on the job was significantly associated with knee pain in both men and women, whereas job-related standing and walking showed no such relationship. As for living conditions, residence on rather steep mountain slopes and the habit of sitting on Japanese tatami mats were significant factors related to knee pain in men, but not in women. There was no association of knee pain with the style of toilet (Japanese or Western). After controlling for all significant factors by multiple logistic regression analysis, age, heavy lifting, and residence on steep slopes were found to be independent factors related to knee pain in men; and age, BMI, and heavy lifting were the factors in women.  相似文献   
94.
The biosynthesis of benastatin A, produced by Streptomyces sp. MI384-DF12, has been studied by feeding experiments with 14C- and 13C-labeled compounds followed by measurement of radioactivity and 13C NMR analysis. The results indicate that benastatin A is derived from two methionine units and fourteen acetate units, condensed in the "head-to-tail" fashion of typical polyketide biosynthesis.  相似文献   
95.
The microvascular growth of ethylnitrosourea-induced rat glioma was observed using vascular casting and scanning electron microscopy (SEM). Light microscopy showed central necrosis and marginal invasive tumor cell growth with increased vascularity, and suggested that adopted pre-existing circulation was dominant in the inoculated brain tumors. In SEM, numerous buds or nodular protrusions and a few large and tortuous vessels along the tumor margin were seen at the early stage. In the intermediate stage, microaneurysms, buds with septum formation and anastomotic arches appeared, and these tumor vessels became more tortuous and larger, and extended as the tumor grew. Several "potato-shaped" huge vessels and linear nodular large vessels also appeared. In the late stage, glomeruli appeared and potato-shaped huge vessels increased in number. The neovascularization and microvascular growth of the tumors was characterized by three patterns: (a) growth of the parent vessels forming buds, (b) vascular growth in a meshwork formation producing glomeruli, and (c) vascular enlargement without a definite pattern creating potato-shaped huge vessels. The tumor vessels gradually lost their natural three-dimensional structure.  相似文献   
96.
Fracture risk is influenced by both bone strength and by falls. Measures of physical function and performance are predictors of falls. However, the interrelationships among bone mineral density (BMD), regular physical activity, and measures of physical performance are not well known. We studied 447 community-dwelling Japanese people aged 40 years and over (96 men and 351 women) to examine the association of calcaneus BMD with measures of physical performance (grip strength, walking speed, chair stand, and functional reach) and regular physical activity. Calcaneus BMD decreased with age by approximately 25% in men and 42% in women. Measures of physical performance decreased with age by approximately 30% in both genders, however, performance on the chair stand test declined by approximately 60%. There were only minimal differences in performance measures and calcaneus BMD between people with and those without regular physical activity in both genders, and most differences were not significant. However, there were significant BMD increases of 3–6% per standard deviation (SD) increase in all performance measures for women and a 7% increase in BMD per SD increase in grip strength for men, after adjusting for age. These associations remained after additional adjustment for body mass index and regular physical activity. These findings suggest that bone density and physical function decline markedly in both men and women with age, and that low BMD and poor function tend to occur together, which would increase fracture risk more than either risk factor alone. Received: 9 August 1999 / Accepted: 4 February 2000  相似文献   
97.
A 73-year-old man with myasthenia gravis required quadruple coronary artery bypass grafting due to triple-vessel disease. Anesthetic management was performed with general anesthesia using a reduced dose of muscle relaxant with the aid of a neuromuscular transmission monitor. He was extubated 14 hrs after surgery without difficulty under this monitor. His postoperative course was uneventful. A patient with myasthenia gravis who required coronary artery bypass surgery was successfully performed by the deliberate preoperative evaluation of patient's myasthenic and cardiac status, and by the careful perioperative management.  相似文献   
98.
To investigate the process of carcinogenesis in gastric cancer, we studied the histological features of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-treated rats. Samples of the gastric mucosa from both MNNG-treated and control rats were histologically examined every 2 months, for 10 months. In 40% of the MNNG-treated rats, atrophy in the gastric mucosa was observed after 2 months, and regenerative epithelium was observed after 4 months, followed by adenomatous proliferation and disappearance of the tight junction electron microscopically after 6 months. A small intestinal cancer had developed in 2 rats at 6 months. While gastric cancer had developed in 3 rats at 8 months, and in one of these 3 rats, peritoneal dissemination was observed macroscopically and histologically. These results suggested that adenomatous proliferation and disappearance of the tight junction observed electron microscopically were characteristic pathological features of precancerous lesions in the stomach in MNNG-treated rat.  相似文献   
99.
A retrospective study of 25 patients treated for primary gastric lymphoma was made to investigate a number of problems related to treatments and report the factors influencing prognosis. In the 5-year-survival rate according to Working Formulation classification, either survival rate of low-grade type or intermediate-grade type was higher than that of high-grade type. Both the 5-year-survival rate of cases without lymph node metastasis and that of cases that involved perigastric lymph nodes were higher than that of cases that involved distant gastric lymph nodes. Those surviving five years after perigastric lymph node metastasis had received D3 or D4 dissection and postoperative multicombined chemotherapy. Tumors invading only to the submucosal layer had received D2 dissection and were not treated by postoperative multicombined chemotherapy, and recurrence was not recognized in these cases. Of 9 cases infiltrating into the musclaris propria or serosa without lymph node metastasis, 8 cases were treated by postoperative multicombined chemotherapy and were alive without recurrence, but one case without postoperative multicombined chemotherapy died by recurrence. Therefore, adequate therapy for gastric lymphoma with infiltrating into submucosal layer is gastrectomy with D2 lymph node dissection, and postoperative multicombined chemotherapy is not necessary. The cases with perigastric lymph node metastasis, or the cases with invading from muscularis propria to serosa require D3 or D4 lymph node dissection with postoperative multicombined chemotherapy. But the cases with distant gastric lymph node metastasis or invading adjacent structure or high-grade type histologically (WF classification) require preoperative chemotherapy.  相似文献   
100.
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