84 research outputs found
Enhanced Auditory Brainstem Response and Parental Bonding Style in Children with Gastrointestinal Symptoms
The electrophysiological properties of the brain and influence of parental bonding in childhood irritable bowel syndrome (IBS) are unclear. We hypothesized that children with chronic gastrointestinal (GI) symptoms like IBS may show exaggerated brainstem auditory evoked potential (BAEP) responses and receive more inadequate parental bonding. = 0.024). Multiple regression analysis in females also supported these findings.It is suggested that children with chronic GI symptoms have exaggerated brainstem responses to environmental stimuli and inadequate parental behaviors aggravate these symptoms
生殖器官の生産量からみたシイ林の有性生殖(林学部門)
松尾大社(京都市嵐山)の境内のシイ成熟林において, リタートラップ法で1986年∿1989年の生殖器官の生産量(林分当たり)を測り, また花粉生産量は開花前の雄花序当たり花粉量を基に推定した。これらの諸量を検討し, 有性生殖についてえた主な結果は次の通りである。花粉生産量は重量(218∿359kg (ha)^ (yr)^)では最大クラス, 粒数(64.2∿103×(10)^(ha)^ (yr)^)では突出して多く, しかも年次変動が小さかった。この莫大な花粉数は, しかし, 胚珠数に見合ったものであった(花粉/胚珠の数比, 4.1∿8.3×(10)^5)。花粉粒は小形であるから(1.94∿4.30×(10)^mg), 同化産物の花粉への流れは節約されている。開花年ごとの乾物量は1609∿1803kg (ha)^で, 雄性と雌性の部分量は逆比例の関係にあった。年度ごとの乾物生産量は1237∿2204kg (ha)^ (yr)^の範囲で, これは種子の並作∿凶作の年の値である。この生産量の多少と各部分の割合との間には, 一定の傾向はなかった。これは種子成熟に2カ年を要することに関係がある。また, 当年生と1年生の部分の生産量は等しくなる年が多かった。結実率は低いが(5.5%∿10.6%), ほかの種と大略等しい。年々の種子数は結実率と並行して推移し, 総雌花数も種子生産に関係があるようだ。種子対投資の重量比は種子の並作年に3倍, 凶作年6倍で, これはほかの重力散布種子の種の値と一致した。In a mature stand of Shii chinkapin (Castanopsis cuspidata SCHOTTKY) at Matsuotaisya shrine, Arashiyama, Kyoto, annual production rates of reproductive organs were studied using 20 litter traps (each 50cm×50cm in mouth area) in 1986-1989,and those of pollen were estimated by multiplying the number of fallen male catkins per ha per year by the mean amount of pollen per catkin before anthesis. The main results were as follows. The pollen production rate of 218-359kg d. w. (ha)^ (yr)^ was one of the highest among other species, and that of 64.2-103×(10)^(ha)^ (yr)^ was by far the largest number; moreover, these showed small year-to-year fluctuations. Such a huge number of pollen grains, however, was balanced by the number of ovules in a stand (numerical ratio of pollen grains to ovules : 4.1-8.3×(10)^5). The light pollen grains (1.94-4.30×(10)^mg d. w.) save the assimilation products invested in pollen formation. Dry matter of reproductive organs by the year of anthesis was within the range 1609-1803kg d. w. (ha)^, and those of male and female parts were inversely proportional to each other. Annual production rates were within the range 1237-2204kg d. w. (ha)^ (yr)^, equivalent to values in years of average to poor seed crop. There was no relationship between the annual production rates (by weight) of male and female parts, because fruit maturation requires two growing seasons. In three years among four, the 0-and 1-yr-old parts showed equal dry weight allocation. Seedmaturing ratios or numerical ratios of mature nuts to total female flowers were small (5.5%-10.6%), being approximately equal to those of other species. The year-to-year trend in nut production (by number) parallelled those of seed-maturing ratio and the number of female flowers. Mean nut weight vs. assimilation products necessary for producing a single nut, calculated by dividing the drymatter production rate of overall parts by the number of nuts, was 1 : 3 in a year with an average seed crop, and 1 : 6 in a year with a poor crop. This seed production effort was similar to those of five other barachorous species
Methylmercury Exposure and Developmental Outcomes in Tohoku Study of Child Development at 18 Months of Age
Seafood is an important component in a healthy diet and may contain methylmercury or other contaminants. It is important to recognize the risks and benefits of consuming seafood. A longitudinal prospective birth cohort study has been conducted to clarify the effects of neurotoxicants on child development—the Tohoku Study of Child Development (TSCD) in Japan. TSCD comprises two cohorts; a polychlorinated biphenyls (PCB) cohort (urban area) and a methylmercury cohort (coastal area). Our previous results from the coastal area showed prenatal methylmercury exposure affected psychomotor development in 18-month-olds, and boys appear to be more vulnerable to the exposure than girls. In this report, we have added the urban area cohort and we reanalyzed the impact of prenatal exposure to methylmercury, which gave the same results as before. These findings suggest prenatal exposure to low levels methylmercury may have adverse effects on child development, especially in boys
Effects of intrauterine exposures to polychlorinated biphenyls, methylmercury, and lead on birth weight in Japanese male and female newborns
Abstract Background The effects of prenatal exposures to polychlorinated biphenyls (PCBs), methylmercury, and lead on birth weight remain disputable. The aim of this study was to investigate whether these chemicals affect birth weight of Japanese newborns, with special emphasis on determining whether these effects differ between males and females. Methods The subjects from Tohoku Study of Child Development, which was designed to examine the developmental effects of prenatal exposures to such hazardous chemicals, were 489 mother-newborn pairs with complete data including smoking habit during pregnancy. Results The mean birth weight of all newborns was 3083 (range, 2412–4240) g. The median values of biomarkers in cord blood were 46.0 (5th and 95th percentiles, 18.6–113.8) ng/g–lipid for total PCBs, 10.1 (4.3–22.4) ng/g for total mercury (THg), and 1.0 (0.6-1.7) μg/dL for lead. The birth weight was significantly heavier in the 252 male newborns than in the 237 female ones. A negative association between total PCBs and birth weight was observed in both male and female newborns, even after adjusting for possible confounders. However, a negative association of THg with birth weight was found only in the male newborns. There was no significant relationship between lead and birth weight in both groups. Conclusion Birth weight appears to be affected by prenatal PCB exposure in Japanese male and female newborns, and the effect of methylmercury exposure on male fetal growth may be stronger than that for females. This implication is that the effects on fetal growth should be assessed in males and females separately
A methodological consideration for blood lead concentrations obtained from the earlobe in Japanese adults occupationally unexposed to lead
Abstract Background Neuropsychological effects of considerably low levels of lead exposure are observed in children, and a reliable and possibly painless technique that can detect such levels is required for the assessment of such exposure. We examined whether the blood lead (BPb) concentrations obtained from the earlobe were as valid and useful as those from the median cubital vein. Methods Paired blood samples were collected from the earlobe and cubital vein of 112 Japanese participants occupationally unexposed to lead, and the BPb levels were determined using ICP-MS. Results The limit of detection of BPb for the ICP-MS method was 0.015 μg/dL, and there was no participant with a BPb level below this limit. The median values of BPb concentrations were 0.91 (range, 0.41–2.48) μg/dL for earlobe blood using a 175-μL capillary tube and 0.85 (0.35–2.39) μg/dL for venous blood using a 5-mL vacuum tube. There was a significant correlation between the earlobe BPb levels and cubital vein BPb levels (Spearman rank correlation r S = 0.941), though the earlobe BPb levels were significantly higher than the cubital vein BPb levels. Most of the participants regarded earlobe puncture as a painless method. Conclusions These data suggest that earlobe BPb levels can be used to assess lead exposure in children. Blood collection using a capillary tube should be done carefully and promptly because slow withdrawal may lead to measurement bias
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