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51.
Morphometric Golgi methods were used to study dendritic development of neurons in the cervical ventral and dorsal horns and the hypoglossal nucleus of 8 victims of sudden infant death syndrome and 20 age-matched control infants. The dendrites and spines of these neurons proliferated rapidly until 28 weeks gestation, then increased slowly until shortly after birth. Dendritic spine density of motor neurons in the cervical anterior horn and hypoglossal nucleus of victims of sudden infant death syndrome was similar to that of the controls. Thus, the delayed maturation of dendritic spines seen in the reticular formation and vagal nuclei is not present in motor neurons of the cervical anterior horn and hypoglossal nucleus.  相似文献   
52.
Immunohistochemical staining with polyclonal antibodies to synthetic amyloid (residues 1-28 of A4) was performed on normal and Down syndrome brains from fetuses to adults. Positive staining appeared in the cytoplasmic processes of astrocytes in the subpial layer and white matter of developing brains, and reappeared in astrocytic fibers of the subpial layer as well as in cerebrovascular and plaque core amyloid in elderly brains. The reappearance of positively stained astrocytes and amyloid occurred earlier in adult Down syndrome patients. The results indicate that the A4 protein is a developmental protein, and its reappearance in Alzheimer and adult Down syndrome brains may be related to the regeneration process.  相似文献   
53.
OBJECTIVE: To assess the status of dietary folate intake, serum and red blood cell (RBC) folate, and related nutritional biomarkers in healthy Japanese women in early pregnancy. DESIGN: A cross-sectional, observational study. SUBJECTS: Pregnant women in the first trimester, at 7-15 weeks gestation (n=70), who were not consuming any folate supplements or folate fortified foods. METHODS: Three-day dietary records were obtained from each subject to assess dietary folate intake. Blood samples were collected for measurement of biomarkers. Biomarkers and nutrient intake were analyzed in two groups defined by their serum folate concentrations: the low folate group (serum folate < 9 ng/ml) and the high folate group (serum folate > or = 9 ng/ml). RESULT: Mean serum and RBC folate concentrations in all subjects were 10.3 and 519 ng/ml, respectively. These levels were remarkably higher than the reported values from many other countries despite our subjects receiving no folic acids supplements. However, mean folate intake by our subjects from natural foods was 289 microg/day, which is thought to be low according to the Japanese dietary recommendation specified for pregnant women. The intake of spinach and fruits was significantly greater in the high folate group than in the low folate group. CONCLUSION: Folate intake was thought to be adequate to maintain a desirable level of serum folate concentration in Japanese pregnant women in the first trimester, although the intake of folate from natural food was not high enough to meet the recommended daily intake.  相似文献   
54.
Background Adequate folate status in pregnancy is important for satisfactory pregnancy outcome. Aim of the Study The objective of the present study was to evaluate folate status in healthy pregnant women by assessing dietary folate intakes and measuring changes in folate-related biomarkers including plasma tHcy, serum vitamin B12 (B12), and serum and RBC folate concentrations in each trimester and to examine their relation to fetal growth. Methods From 94 pregnant women, 3-day-dietary records were obtained and blood was collected for plasma total homocysteine (tHcy), serum B12, and serum and red-blood cell (RBC) folate measurements. Infant anthropometric measurements were made immediately after birth. Results Average folate intake was less than 300 μg/day with a mean energy intake of about 1800 kcal. Mean serum and RBC folate concentrations declined significantly during gestation (p < 0.05). Mean serum B12 also significantly decreased (p < 0.01), whereas plasma tHcy increased from 5.1 in the first trimester to 5.9 μmol/l in the third trimester (p < 0.01). Multiple regression analyses, after controlling for maternal age, parity and pre-pregnancy body-mass index indicated that a 1.0 μmol/l increase in plasma tHcy in the third trimester corresponded to a 151 g decrease in birth weight (p < 0.01). Neither B12 nor folate concentrations in all three trimesters showed any significant associations with birthweight. Plasma pyridoxal-5′-phosphate concentrations were markedly low, and were consistent with low intake of vitamin B6 in our population. Conclusion Our data suggest that higher plasma tHcy in the third trimester is a predictor of lower birth weight. In general, the dietary intake of B-vitamins and energy may be inadequate in our population, suggesting intervention is necessary.  相似文献   
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56.
We present a case of small cell lung cancer whose shadow resembles bead son chest radiographs. An 81-year-old woman who had been receiving treatment from her doctor for pulmonary emphysema and chronic respiratory failure consulted our department because a small nodular shadow had been detected radiographically in the right lower lung field. The bead-like shadows in the radiographs and tomograms extended from the periphery of the right lower lobe to the pulmonary hilum. This case of small cell lung cancer appeared in chest radiographs to have an unusual shape.  相似文献   
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58.
We reported a 67-year-old woman who had developed abnormal behavior and dementia from January 21, 2001 and deteriorated to akinetic mutism on February 15. T2-weighted magnetic resonance imaging showed high intensity in bilateral globus pallidus and a rapid spreading of diffuse high intensity in bilateral deep white matter. Later on, we got an important information that she had used a little coal stove three times about three weeks before presenting the initial symptom. She was diagnosed as carbon monoxide intoxication and treated with hyperbaric oxygen from March 1. A remarkable improvement on dementia and motor disability was observed. We conclude that this case is the first reported example of a case of intermittent carbon monoxide intoxication presenting subacute dementia as an initial symptom.  相似文献   
59.
The present study was undertaken to define optimal conditions for cryopreservation of fetal rat liver tissue fragments. First, various cooling rates (1, 4, 10, 20 and 30 degrees C/min) and preserving temperatures (-20, -80 and -196 degrees C) were examined. Next, various concentrations of Me2SO (5, 10, 20 and 30 per cent vol/vol) were examined by freezing at a rate of 4 degrees C/min to -80 degrees C before transfer to -196 degrees C. All samples were preserved for at least one week. After recovery from cryopreservation, the fragments were transplanted into the spleens of syngeneic rats. Histological assessment of the grafts was made one month after transplantation. Consequently, the optimal cryopreserving conditions for fetal rat liver fragments were defined as follows: cooling rate was 1 to 10 degrees C/min, preserving temperature was at -196 degrees C, concentration of Me2SO was 20 per cent (final concentration: 10 per cent). In the long term observation, the stored liver fragments could be differentiated into adult hepatocytes and the surviving hepatocytes showed little difference from the nonfrozen controls, either histochemically or ultrastructurally. The surviving hepatocytes in the stored transplants were less numerous than in the nonfrozen ones and hepatic cell plates and sinusoids were nil.  相似文献   
60.
We reported a 45-year-old man who had repeated isolated thoracic spinal cord lesion on MRI in the clinical course of seven years. He had transient bilateral plantar numbness and urinary retention on December, 1994. Then, spastic paraplegia, total anesthesia of feet, and severe sphincter disturbance struck him on May, 1995. He was diagnosed as incomplete Beh?et's disease and neuro-Beh?et's disease on June, 1995 because of recurrent oral aphta, genital ulceration, and foliculitis. T2-weighted magnetic resonance imaging showed high intensity enhanced with Gd-DTPA in thoracic spinal cord from Th 5 to 8 level. Any other abnormal lesion on brain or spinal MRI was not observed. He was treated with corticosteroids and recovered incompletely. Another two big attacks occurred to him. No new lesion but thoracic spinal cord lesion was observed. We conclude that this case is the first reported example of neuro-Beh?et's disease with repeating isolated thoracic spinal cord lesion.  相似文献   
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