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61.
To analyze a population's marital structure with respect to the ethnicity and birthplace of the spouses and to estimate the indices of endogamy, migration, and marriage assortativeness, the records of marriages in Tomsk during two periods of time (1970-1972 and 1985-1990) were studied. The parameters of the population-genetic and demographic structure proved to change during the studied period: the endogamy index and the indices of marriage assortativeness increased, and the migration index decreased. These data suggest that the genetic structure of the Tomsk urbanized population stabilized with time and that the intrapopulation subdivision decreased (a tendency for panmixia).  相似文献   
62.
The presence of 5-3deltabeta-hydroxysteroid dehydrogenase, IIbeta-hydroxysteroid dehydrogenase, 17beta-hydroxysteroid dehydrogenase and glucose-6-phosphate dehydrogenase has been demonstrated histochemically in the adrenal gland of the rain quail Coturnix coromendalica, barn owl Tyto alba, brown crake Amaurornis akool and painted partidge Francholinus pictus. All these enzymes occurred in the inter-renal cells. No activity was observed in the chromaffin cells. It is suggested that the inter-renal cells of these four species of birds are capable of synthesizing both corticosteroids and sex steroids.  相似文献   
63.
A PET‐MRI fusion system is developed for molecular‐genetic imaging. The purpose of the system is to obtain images of the in‐vivo human brain using two high‐end imaging devices, an advanced PET and an ultrahigh‐field MRI. These are the HRRT‐PET, a high‐resolution research tomograph dedicated to brain imaging on the molecular level, and the 7.0‐T MRI, an ultrahigh field version used for morphological imaging. HRRT‐PET delivers high‐resolution molecular imaging with a resolution down to 2.5 mm FWHM, which is currently the highest spatial resolution available for the observation of the human brain's molecular activities, including enzymes and receptors, which are manipulated genetically, such as reporter genes and probes. The 7.0‐T MRI began to reveal submillimeter resolution images of the cortical as well as deep brain areas, down to 250 μm, which allows us to visualize the fine details of the cortical and brainstem areas, including the line of Gennari in the visual cortex and the corticospinal tracts in the pontine area. The current PET‐MRI fusion imaging system produces the highest quality images of molecular and genetic activities of the human brain in vivo. It is starting to provide many answers to the key questions about the neurological diseases. Some of these start providing answers to many cognitive neuroscience problems with clear molecular and genetic bases. There is great potential in the PET‐MRI for early diagnosis of cancers as well as other neurological diseases, which we were previously unable to diagnose, such as microscopic molecular changes that occur in Parkinson's and Alzheimer's diseases. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 252–265, 2007  相似文献   
64.
This study explodes the relationships between the height adjustment of bed sectors and subjective comfort depending on three types of sleeping positions. An adjustable bed system that regulates the heights of 8 adjustment sectors of the bed was developed. To evaluate the comfort of 9 body areas, subjective ratings were requested from 64 subjects ranging in age from 25 to 50. The subjects included 29 males and 35 females. For an objective evaluation, the patterns of pressure distribution were investigated according to the three sleeping positions. During two separate states (before bed adjustment and after bed adjustment), measurements of the adjusted bed height and pressure distribution, and subjective ratings according to three sleeping positions were performed. Based on the results of the adjusted heights of the 8 sectors in the bed, the subjects preferred the W‐shaped sleeping posture in both the supine and side positions. However, the U‐shaped sleeping posture was preferred in the prone position. With respect to these sleeping positions, the heights of sectors significantly correlated with the subjective ratings presented by the subjects, as well as the ratios of pressure. © 2009 Wiley Periodicals, Inc.  相似文献   
65.
Experiments were designed to determine whether the omega 3-unsaturated fatty acid eicosapentaenoic acid affects the production of nitric oxide evoked by interleukin-1 beta in cultured vascular smooth muscle cells. Incubation of cultured rat or human aortic smooth muscle cells with interleukin-1 beta evoked a time- and concentration-dependent release of nitrite, an oxidation product of nitric oxide. The exposure of cells to interleukin-1 beta in combination with eicosapentaenoic acid caused a significantly larger production of nitrite than that evoked by the cytokine alone. The potentiation by eicosapentaenoic acid was concentration-dependent. The production of nitrite evoked by equieffective concentrations of interleukin-1 beta in the presence and absence of eicosapentaenoic acid were inhibited to a similar extent by nitro L-arginine (an inhibitor of nitric oxide synthase), transforming growth factor beta 1, platelet-derived growth factorAB and thrombin. The addition of interleukin-1 beta-activated smooth muscle cells to suspensions of washed and indomethacin-treated platelets inhibited the aggregation caused by thrombin. The inhibitory effect was enhanced when the smooth muscle cells were exposed to the cytokine in the presence of eicosapentaenoic acid prior to the experiment. Smooth muscle cells exposed to interleukin-1 beta and eicosapentaenoic acid did not affect platelet aggregation in the presence of oxyhemoglobin or methylene blue. Untreated cells or cells exposed to the fatty acid alone did not have such effects. These observations suggest that eicosapentaenoic acid potentiates the production of nitric oxide evoked by interleukin-1 beta in vascular smooth muscle.  相似文献   
66.
Kimchi fermentation usually relies upon the growth of naturally-occurring various heterofermentative lactic acid bacteria (LAB). This sometimes makes it difficult to produce kimchi with uniform quality. The use of Leuconostoc mesenteroides as a starter has been considered to produce commercial fermented kimchi with uniform and good quality in Korea. In this study, a combination of a barcoded pyrosequencing strategy and a 1H NMR technique was used to investigate the effects of Leu. mesenteroides strain B1 as a starter culture for kimchi fermentation. Baechu (Chinese cabbage) and Chonggak (radish) kimchi with and without Leu. mesenteroides inoculation were prepared, respectively and their characteristics that included pH, cell number, bacterial community, and metabolites were monitored periodically for 40 days. Barcoded pyrosequencing analysis showed that the numbers of bacterial operational taxonomic units (OTU) in starter kimchi decreased more quickly than that in non-starter kimchi. Members of the genera Leuconostoc, Lactobacillus, and Weissella were dominant LAB regardless of the kimchi type or starter inoculation. Among the three genera, Leuconostoc was the most abundant, followed by Lactobacillus and Weissella. The use of Leu. mesenteroides as a starter increased the Leuconostoc proportions and decreased the Lactobacillus proportions in both type of kimchi during kimchi fermentation. However, interestingly, the use of the kimchi starter more highly maintained the Weissella proportions of starter kimchi compared to that in the non-starter kimchi until fermentation was complete. Metabolite analysis using the 1H NMR technique showed that both Baechu and Chonggak kimchi with the starter culture began to consume free sugars earlier and produced a little greater amounts of lactic and acetic acids and mannitol. Metabolite analysis demonstrated that kimchi fermentation using Leu. mesenteroides as a starter was completed earlier with more production of kimchi metabolites compared to that not using a starter, which coincided with the decreases in pH and the increases in bacterial cell number. The PCA strategy using all kimchi components including carbohydrates, amino acids, organic acids, and others also showed that starter kimchi fermented faster with more organic acid and mannitol production. In conclusion, the combination of the barcoded pyrosequencing strategy and the 1H NMR technique was used to effectively monitor microbial succession and metabolite production and allowed for a greater understanding of the relationships between the microbial community and metabolite production in kimchi fermentation.  相似文献   
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68.
Gleason's score (GS) has been reported to be the most valuable prognostic factor in cases of prostate cancer. GS is solely dependent on the histological architecture of the prostate cancer, but, it seems doubtful that histological patterns are sufficient for evaluating the degree of malignancy of prostate cancer. We previously reported that the estimation of volume-weighted mean nuclear volume (MNV) might be a more useful prognosticator for prostate cancer than subjective histological grading. However, the previous study was conducted on patients treated in a single hospital, and the number of subjects was too small to draw a definitive conclusion. In this study, we analyzed a larger number of subjects at another institution using a blinded study design. A retrospective prognostic study of 195 patients with prostate cancer diagnosed between January 1966 and December 1988 at Kyoto University Hospital, and treated by conservative therapy, was conducted. Unbiased estimates of MNV were compared with the clinical stage and histological grading according to GS with regard to the prognostic value. Univariate analysis revealed that estimates of MNV, clinical stage, and GS all correlated significantly with disease-specific survival in cases of prostate cancer. Multivariate analysis of all cases also revealed that all of these factors were significant independent prognosticators of disease-specific survival. However, focusing on clinically localized cases (stages A, B, and C), multivariate analysis revealed that the estimation of MNV was the only powerful prognosticator of prostate cancer. This study indicates that the estimation of MNV is prognostically equal or superior to GS in cases of prostate cancer. We emphasized that the estimates of MNV is a more objective method for histological grading to predict the malignant potential of prostate cancer.  相似文献   
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70.
0 引言 为了在用能效率上作出工程努力,Cortagena技术大学去年4月已决定实施一项雄心勃勃的计划,要在此后的4年中削减用电费用。为了证实不同政策的可行性和成本效益,应用于原海军医院(工业工程高等技术学校总部)的许多展示活动将在最近期内完成。当然,在此建筑中合理用电的对象将集中在两个主要的电气末端即:电  相似文献   
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