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91.
92.
Background
Variance of peak bone mass has a substantial genetic component, as has been shown with twin studies examining quantitative measures such as bone mineral density (BMD) and quantitative ultrasound (QUS). Evidence implicating single nucleotide polymorphisms (SNPs) of the transforming growth factor beta-1 (TGFB1) gene is steadily accumulating. However, a comprehensive look at multiple SNPs at this locus for their association with indices of peak bone mass has not been reported. 相似文献93.
Abstract The purpose of the present study was to investigate how bright light during the daytime could influence circadian rhythms of core temperature and nocturnal sleep. Seven females (age 20 ± 2 years) served as participants. The participants lived in the experimental unit for 4 days and were exposed to either 6000 lx (bright) or 200 lx (dim) light during the daytime. Rectal temperature (Tre ) was measured during the experimental period. Subjective alertness was measured by the Kansei-gakuin Sleeping Scale five times a day. The minimum Tre was significantly lower after bright exposure ( P < 0.05). The Tre fell rapidly after bright exposure before they retired ( P < 0.05) and increased more rapidly during bright light after they woke up ( P < 0.05). The morning wakefulness under bright exposure was more active than under dim exposure ( P < 0.05). The melatonin secretion at wake up during bright exposure was significantly lower than during dim exposure ( P < 0.05). Exposure to bright light during daytime lowered the nocturnal level of Tre , its evening fall was faster and the morning rise quicker. This suggests that indoor light during daytime should be bright enough to promote healthy sleep at night. 相似文献
94.
Scales for the measurement of attitudes toward blood donation 总被引:1,自引:0,他引:1
Attitudes toward blood donation are frequently assumed to vary along a single dimension from unfavorable to favorable. In contrast, theories of attitude structure specify three distinct attitude components: affect, cognition, and behavior. This article describes the development of three new scales for the measurement of affective, cognitive, and behavioral components of attitudes toward blood donation. The scales were developed using the method of equal-appearing intervals and were administered to both donors of blood and nondonors. Correlations among the scales were relatively small and supported the three-component distinction. Affect was more strongly correlated with the number of prior donations than was cognition, which suggested an important role for emotional factors in blood donation. Scores on all three scales showed the attitudes of blood donors to be more favorable than those of nondonors. 相似文献
95.
Spinocerebellar ataxia type 7 (SCA7): a neurodegenerative disorder with neuronal intranuclear inclusions 总被引:8,自引:13,他引:8
Holmberg M; Duyckaerts C; Durr A; Cancel G; Gourfinkel-An I; Damier P; Faucheux B; Trottier Y; Hirsch EC; Agid Y; Brice A 《Human molecular genetics》1998,7(5):913-918
Autosomal dominant cerebellar ataxia with progressive macular degeneration
is caused by a CAG/glutamine repeat expansion in the SCA7 gene/protein.
Neuronal intranuclear inclusions were detected in the brain of an early
onset SCA7 case with the 1C2 antibody directed against an expanded
polyglutamine domain. Nuclear inclusions were most frequent in the inferior
olivary complex, a site of severe neuronal loss in SCA7. They were also
observed in other brain regions, including the cerebral cortex, not
considered to be affected in the disease. Using confocal microscopy we
showed that some inclusions were ubiquitinated, but to varying degrees,
ranging from <1% in the cerebral cortex to 60% in the inferior olive. In
addition, we also observed cytoplasmic staining using the 1C2 antibody,
particularly in the supramarginal gyrus, the hippocampus, the thalamus, the
lateral geniculate body and the pontine nuclei. These data confirm that the
presence of intranuclear inclusions in neurons is a common characteristic
of disorders caused by CAG/polyglutamine expansions, but unlike what has
been reported for Huntington's disease, SCA1 and SCA3/MJD, in SCA7 the
inclusions were not restricted to the sites of severe neuronal loss.
相似文献
96.
Genetic analysis of epidermal growth factor action: assignment of human epidermal growth factor receptor gene to chromosome 7. 总被引:5,自引:6,他引:5 下载免费PDF全文
R L Davies V A Grosse R Kucherlapati M Bothwell 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(7):4188-4192
Purified murine epidermal growth factor (EGF) binds to mouse and human cells. Two mouse transformed cell lines of different origins, PG19 and B82, were found to lack EGF receptors (EGFR). The defect in each of these two cell lines seems to be identical because they fail to complement each other. Somatic cell hybrids between these EGFR-deficient mouse cells and human cells expressing EGFR were produced. Several of these hybrids bound labeled EGF. Detailed cytogenetic analysis of these cell hybrids, followed by correlation of EGFR expression with human chromosomes revealed that EGFR presence correlated with human chromosome 7. The results suggest that the structural gene or a gene necessary for expression of the human EGF receptor is located on human chromosome 7. 相似文献
97.
Mulkerrin EC; Clark BA; Epstein FH 《QJM : monthly journal of the Association of Physicians》1997,90(6):411-415
We studied blood pressure and natriuretic responses to acute salt loading,
and the effect of non-steroidal anti-inflammatory agents on these
responses, in five healthy normotensive women aged 65 to 71 years. Five
women aged 25 to 31 years acted as controls. Intravenous saline loading,
with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h.
Baseline blood pressures were higher in the elderly. Saline infusion
without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in
the older group only. Ibuprofen increased baseline SBP in the elderly (129
+/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen
again raised blood pressure by about 25 mmHg in the elderly only. The
elderly group showed markedly increased sodium excretion during saline
loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP
or sodium excretion in controls. Ageing appears to increase susceptibility
to salt retention and hypertension from non-steroidal anti-inflammatory
agents.
相似文献
98.
Amplification of genes encoding human myeloid membrane antigens after DNA-mediated gene transfer 总被引:2,自引:0,他引:2
Spontaneous amplification of genes encoding two different human myeloid surface antigens was observed after DNA-mediated gene transfer of cellular DNA from the human myeloid cell line HL-60 into NIH-3T3 mouse fibroblasts. Transformed recipient cells with highly amplified expression of either of two donor membrane polypeptides, gp150 or p67, were isolated with a fluorescence-activated cell sorter (FACS), using monoclonal antibodies specific for human myeloid cells. Immunoprecipitation of enzymatically radioiodinated polypeptides from the surface of transformed NIH-3T3 cells confirmed that expression of these proteins was amplified tenfold to 20-fold in comparison to their expression on human myeloid cell lines. The cellular DNA of cloned secondary and tertiary transformants expressing high levels of gp150 and p67 contained amplified sets of DNA restriction fragments that hybridized with human repetitive DNA sequences. Cytogenetic analysis of subclones overexpressing gp150 revealed extrachromosomal double minutes (DMs), whose presence correlated with the unstable expression of the membrane polypeptide. Human sequences in gp150-positive clones did not localize to chromosomes, consistent with their association with extrachromosomal DMs. By contrast, p67-positive subclones stably expressed the antigen, and in situ hybridization to metaphase spreads demonstrated that amplified human DNA sequences were integrated into a specific marker chromosome. Cytogenetic analysis of the parental NIH- 3T3 subclone used in these studies disclosed DMs in a low percentage of metaphases, suggesting that the recipient cells have a propensity for amplifying donor DNA. 相似文献
99.
Pretreatment hematocrit in 117 advanced-stage Hodgkin's disease patients treated with a combined modality therapy program was evaluated as an independent prognostic variable with regard to survival and relapse-free survival. Age greater than 40 years, and multiple extranodal sites of involvement were found to be statistically significant independent negative prognostic factors with regard to survival. Pretreatment hematocrit, however, was not an independent negative prognostic variable. 相似文献
100.
The Effects of Ascorbic Acid Supplementation on the Absorption of Iron in Maize, Wheat and Soya 总被引:2,自引:0,他引:2
M. H. Sayers S. R. Lynch P. Jacobs R. W. Charlton T. H. Bothwell R. B. Walker F. Mayet 《British journal of haematology》1973,24(2):209-218
The absorption of iron from three staple vegetables was measured by the red cell utilization method in iron deficient subjects. The food iron had been labelled with 55 Fe by the hydroponic cultivation method. In addition, 59 Fe was added with or without carrier iron in the form of ferric ammonium citrate, prior to cooking. The constant relationship reported by others between the absorption of the two isotopes was confirmed, suggesting that the extrinsic iron and the food iron were absorbed from a common pool. The addition of ascorbic acid to maize porridge before cooking significantly enhanced the absorption of both the intrinsic and the added iron. However, no effect was noted with soya biscuits or with whole wheat bread (100% extraction). Evidence was obtained that these differences were due to the oxidative destruction of the ascorbic acid by the high temperatures required for baking. If, therefore, a feasible method were found for supplementing vegetable foodstuffs with ascorbic acid and inorganic iron, nutritional benefit would only be anticipated with uncooked or boiled foods. 相似文献