Masaharu Yamamoto

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We explored the risk factors for gallbladder cancer and explanations for its sharp and constant incidence increase in Chile since the 1970s. We compared 114 consecutive patients with verified gallbladder cancer, diagnosed 1992-1995, to 114 matched hospital patients with gallstones, using conditional logistic regression analysis. Low education showed a(More)
The attainment of maximal peak bone mass early on in life is one of the most important strategies for the prevention of osteoporosis in women. The aim of this study was to clarify the correlation between gains in body size in all growth phases in childhood and adult bone mass in women. The subjects were 86 female first-year university students, aged 18–21(More)
AIM To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary. METHODS We examined 42 cases of gallbladder carcinoma: 22 Japanese and 20 Hungarian cases. p53 mutations at exons 5 to 8 and K-ras mutations at codon 12 were tested by direct sequencing.(More)
In anesthetized albino rabbits, ampullary branches of the vestibular nerve were stimulated electrically. Prominent and stable reflex contraction was induced in extra-ocular muscles by applying single current pulses of relatively long duration, 3–5 msec. Survey with a glass microelectrode revealed that, during application of relatively wide pulses to a(More)
We propose a method of reducing substrate noise and random fluctuations utilizing a self-adjusted forward body bias (SA-FBB) circuit. To achieve this, we designed a test chip that contained an on-chip oscilloscope for detecting dynamic noise from various frequency noise sources, and another test chip that contained 10-M transistors for measuring random(More)
Chilean red chili peppers contaminated with aflatoxins were reported in a previous study. If the development of gallbladder cancer (GBC) in Chile is associated with a high level of consumption of aflatoxin-contaminated red chili peppers, such peppers from other countries having a high GBC incidence rate may also be contaminated with aflatoxins. We aimed to(More)
Our previous study indicated an association of chili pepper consumption with gallbladder cancer (GBC) in the presence of gallstones (GS) in Chile. We investigated whether or not a similar association was present in Hungary, where mortality from GBC is high and chili peppers are frequently consumed. In a case-control study, we compared 41 female GBC patients(More)
In anesthetized albino rabbits, electric stimulation of vestibular nerve branches innervating semicircular canals produced not only reflex contraction in certain extraocular muscles, but also a transient relaxation in others. From relaxing muscles was recorded a slow muscle potential that reflected depression of spontaneous spike discharges in muscle(More)
Little has been understood about vitamin D status in relation to bone health in Asian women. The purpose of this study was to identify how the serum 25-hydroxyvitamin D (25[OH]D) concentration is associated with bone mass and bone metabolism. This cross-sectional, community-based epidemiologic study was conducted among 600 ambulatory postmenopausal women.(More)
To date, no study has investigated the nutritional status of vitamin D in frail elderly people living at home. The purposes of this study were to assess serum 25-hydroxyvitamin D (25[OH]D) levels and associated factors in noninstitutionalized elderly people who had various levels of physical disability, and to propose an adequate vitamin D nutritional(More)