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31.
Skinfold thicknessess (SFT) were measured at ulnar, triceps, subscapular and suprailiac sites in 730 boys and 724 girls (age 3–12 years) whose stature ranged from 100 to 150 cm and whose weight was within ±20% of the average. Means and standard deviation (SD) were calculated after logarithmic transformation of the original skinfold readings to demonstrate stature-based standards of SFT in Japanese children. The means of SFT exhibited nadirs (boys/ girls: ulnar 5.1/5.9 mm, triceps 7.9/9.5 mm, subscapular 4.9/6.1 mm, suprailiac 4.5/6.2 mm) in subjects 110–115 cm tall except for ulnar SFT in girls. SFT values increased as children increased in stature. Standard deviations of SFT at the four sites in short children (staturte < mean ?1 SD) were estimated using the stature-based standard as well as an age-based standard. Susms of the SDs assessed by the age-based standard were significantly smaller than those assessed by the stature-based standard in boys (P < 0.05) and girls (P < 0.01) with short stature, suggesting that SFT in short children was falsely understimated by the age-based standard. Thus, the stature-based standard is beneficial for the assessment of SFT, especially in children whose stature is below the mean ?-1 SD. © 1995 Wiley-Liss, Inc.  相似文献   
32.
Previous physiological and pharmacological studies have shown that the serotonin2A (5-HT2A) receptor is involved in cerebellar functions. However, the expression of 5-HT2A receptors in the developing cerebellum has not been elucidated to date. In the present immunohistochemical study, we examined developmental changes of the distribution of 5-HT2A receptors in Purkinje cells of the rat cerebellum from embryonic day 18 (E18) to postnatal day 21 (P21). The weak immunoreaction to 5-HT2A receptors was found in the deep cerebellar nuclei on E19. In the cerebellar cortex of the hemisphere and the posterior vermis, somata of Purkinje cells became weakly immunoreactive on P0. With the dendritic elongation and arborization, the immunoreaction appeared in the proximal parts of Purkinje cell dendrites. Distal parts of the dendrites became immunoreactive after P12, and were strongly immunolabeled by P21. The present study may provide a structural basis to investigate the roles of 5-HT2A receptors during the cerebellar development.  相似文献   
33.
Immediate hemolytic transfusion reactions (IHTR) occurred in the course of delayed hemolytic transfusion reactions (DHTR). An 84-year-old man had received a blood transfusion 20 years ago. Progressive anemia developed, because of continuous bleeding from a bladder tumor. He was transfused with concentrated red blood cells (CRC) which were Rh-E antigen negative, because he had anti-E antibodies (day 0). He received CRC on day 3, and underwent resection of bladder tumor on day 6. Although crossmatch-compatible CRCs were prepared for the operation, those were not required and were kept in a refrigerator in the ward. On day 9, when a CRC kept in the ward was transfused, he suddenly had a IHTR. In order to analyze a mechanism of IHTR, the anti-Jk(b) and anti-Di(b) antibodies, anti-HLA antibodies and the concentrations of inflammatory cytokines were measured in serum samples. The anti-Jk(b) and anti-Di(b) antibodies increased prior to IHTR experienced on day 9. The concentrations of IL-6 and IL-1beta increased from day 2, while the concentration of IL-8 increased from day 7. The anti-HLA class I antibody could be detected 2 days before IHTR. Thus, the anti-Jk(b) and anti-Di(b) antibodies induced the production of inflammatory cytokines and symptoms of DHTR and IHTR. The anti-HLA class I antibody could be produced in spite of using the filer for removing leukocytes, and may take part in the induction of IHTR. Further, blood products should be transfused soon after completing a crossmatch test in patients with anti-RBC alloantibodies.  相似文献   
34.
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts.  相似文献   
35.
Imogolite, a natural product in the clay fraction of Japanese soil, was characterized through its dilute solution properties. Various methods were employed for this characterization, including viscosity, sedimentation, static/dynamic light scattering, and small angle X-ray scattering. All these measurements have revealed consistently that imogolite is represented by a rigid thin rod within the accuracy of available theories, where its repeat unit is composed of twelve gibbsite units. Since the evaluation of the chain length from the observed quantities depends on the molecular weight distribution, its effect was also considered where Mw/Mn ≈ 1,2 was estimated from the sedimentation profile.  相似文献   
36.
A 1,268-bp polynucleotide probe for heat-labile and heat-stable enterotoxins (LTh, STIa, STIb) was conjugated with horseradish peroxidase (HRP). The HRP-conjugated trivalent probe was applied to the detection of enterotoxigenic Escherichia coli (ETEC) by colony and stool hybridizations. The binding of the probe to its targets was assayed by the addition of HRP substrates hydrogen peroxide and luminol in the presence of an enhancer, and the chemiluminescence was recorded by exposure to X-ray film. Slot blot hybridization demonstrated that the HRP-conjugated trivalent probe specifically hybridized with the DNA isolated from ETEC strains. The trivalent probe also specifically identified bacterial colonies of ETEC that produced LTh, STIa, STIb, LTh-STIa, or LTh-STIb. Treatment of targets with sodium dodecyl sulfate and proteinase K remarkably reduced nonspecific hybridization to DNAs of non-ETEC strains. Furthermore, this probe was able to detect stool specimens seeded with 10(2) original ETEC cells per 5 mg of feces. These results suggest that the HRP-conjugated trivalent probe is a candidate for use in the clinical laboratory to detect ETEC.  相似文献   
37.
Although frequently encountered, no available consensus about the association between skeletal abnormalities and skin pigmentation. Several syndromes are characterized by the presence of skin pigmentation in association with skeletal disorders like neurofibroamtosis 1, McCune-Albright Syndrome, Jaffe-Campanacci Syndrome and Jaffe-Lichtenstein Syndrome. Even in the absence of these syndromes, skeletal abnormalities were detected in all radiologically examined patients having patterned skin pigmentation. Although skin pigmentation is controlled by several factors, melatonin is the most reliable factor to have relation to development of skeletal abnormalities. Recent research works support that melatonin might play a role in bone development and several hypotheses link melatonin with some bone diseases associated with skin pigmentation. It seems that melatonin deficiency is a probable operating co-factor in a lot of clinical situations characterized by skin pigmentation and skeletal disorders. This would explain some of the un-explained observations related to these syndromes and research works along these lines might lead to the development of efficient treatment for these diseases.  相似文献   
38.
With electrophysiological techniques, we found phase-dependent modification of the efficacy of signal transmission in the procerebrum (PC), the oscillatory olfactory center, of the terrestrial mollusk Limax marginatus and elucidated its neuronal mechanism. Previous studies have indicated that about 10(5) PC neurons can be classified into only two types: bursting (B) neurons and nonbursting (NB) neurons, and both types of neurons have ongoing and phase-locked periodic oscillation of their membrane potentials. On olfactory nerve stimulation, excitatory postsynaptic potentials (EPSPs) were evoked with a constant latency in NB neurons, while EPSPs with a variable latency were evoked in B neurons. These findings suggest a monosynaptic connection from the olfactory nerve to NB neurons, but a polysynaptic connection between the olfactory nerve and B neurons. This polysynaptic transmission is most likely mediated by NB neurons because the olfactory nerve makes synaptic connection only with NB neurons in the PC. The latency of the evoked EPSPs in B neurons depended on the phase of the PC oscillatory activity, presumably because of the oscillation of the intervening NB neurons. These results suggest that the efficacy of olfactory nerve-B neuron polysynaptic transmission is regulated by the activity level of the phasically oscillating NB neurons. Thus, the intrinsic oscillation in the PC can serve as a filter for olfactory information conveyed from the olfactory nerve as a train of neuronal spikes. This filtering system may also produce a phase-dependent modification by the olfactory input of the PC oscillation frequency.  相似文献   
39.
The acidic aqueous solution of imogolite is proposed to be an ideal lyotropic system. No temperature dependence was marked on the two phase boundary concentrations (A and B points) of imogolite solutions as predicted by the theories of Flory and Onsager. A satisfactory quantitative agreement was observed with Onsager's theory. The polydispersity of rod lengths was found to shift the A point towards lower concentrations than expected from theory.  相似文献   
40.
Summary In this study we attempted to determine the effects of exercise training at the intensity corresponding to lactate threshold (Thla ) on various health-related variables in sedentary but apparently healthy elderly subjects. Six men and five women volunteers [mean age 68.9 (SD 3.4) years] performed supervised endurance-type training on stationary cycle ergometers for 30 min and recreational activities for 30 min, 3 days a week for 12 weeks. Four men and four women served as the control group [68.8 (SD 4.4) years]. As a result of the training programme, statistically significant increases in maximal oxygen consumption (10%), oxygen consumption at Thla (18%), distance covered in 12-min walk, side step, and leg extensor power were found in the training group, while no changes occurred in the control group. The changes in serum cholesterol and triglyceride concentrations from the pre- to post-training period were statistically significant. High-density lipoprotein cholesterol remained unchanged, and low-density lipoprotein cholesterol tended to decrease following the training programme. These data would indicate that exercise training at the intensity corresponding to Thla may have favourable effects on overall physical fitness and some serum lipid variables in older individuals.  相似文献   
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