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121.
Air quality of American homes 总被引:1,自引:0,他引:1
In a survey of particulate fallout in homes it was found that there is a relation between pollution inside and outside a home. The level inside the home also depends on the location of the home (urban, suburban, or rural). Bathrooms and kitchens show heavier particle fallout than living rooms or bedrooms. 相似文献
122.
Schaefer BF 《Science (New York, N.Y.)》2005,308(5726):1267-1268
123.
S H Boyer A N Noyes G R Vrablik L J Donaldson E W Schaefer C W Gray T F Thurmon 《Science (New York, N.Y.)》1971,171(967):182-185
Small quantities of unusual hemoglobins were found in 1 of 37 chimpanzees and 2 of 6 gorillas. In each genus these hemoglobins contain unique alpha chains that differ from the ordinary by eight to nine scattered amino acid changes. The unusual chains arise from a hitherto undetected hemoglobin (3)alpha locus. No (3)alpha products are found in most apes; accordingly, (3)alpha is considered synthetically inactive in all but a few reversion mutants. Indirect evidence that the inactive (3)alpha locus is juxtaposed to an active alpha locus together with the supposition that (3)alpha exists in man provides a setting wherein thalassemia might be produced by nonhomologous recombination between two loci. 相似文献
124.
125.
Bis(3-fluorosalicylaldehyde) ethylenediimine cobalt(II), a reversible oxygen-carrying compound, has been crystallized as a tetramer with two oxygen molecules bound to the four cobalt atomns, each oxygen molecule bridging between two metal atoms. These dimers are further linked by two bonds between the oxygen atom of the salicylaldehyde and the cobalt atom. The oxygen-to-oxygen distance, 1.21 angstroms in molecular oxygen, has increased to 1.308(28) angstroms (where the number in parentheses is the estimated standard deviation) in this compound, the shortest distance yet observed in sutch a bridging arrangement. 相似文献
126.
Schaefer VJ 《Science (New York, N.Y.)》1970,170(3960):851-852
When relatively clean country air is exposed to the saturated vapor of iodine or turpentine, very large numbers of condensation nuclei develop. It is believed that such air contains clusters of molecules that are polymerized by the vapor of turpentine or iodine to form nuclei. 相似文献
127.
128.
A Tvarijonaviciute JD Carrillo‐Sanchez JJ Ceron 《Reproduction in domestic animals》2013,48(3):520-524
The aim of this study was to evaluate the possible association between hormonal changes that occur during oestrus and biomarkers related with glucose metabolism (glucose and insulin), lipid metabolism (lipidic profile and BChE) and adipokines (adiponectin and ghrelin) in healthy bitches. For this purpose, we measured these analytes in serum of bitches, at two times: before (T1) and after (T2) the LH peak that were established according to progesterone concentrations. Increased levels of total cholesterol (p < 0.01), high density lipoprotein cholesterol (HDL‐C) (p < 0.01), low density lipoprotein cholesterol (LDL‐C) (p < 0.01), adiponectin (p < 0.01) and ghrelin (p < 0.05) were observed at T2 in comparison with T1. No statistically significant changes were observed in serum glucose, insulin, homoeostasis model assessment for insulin sensitivity (HOMA), triglycerides and BChE. When all data of T1 and T2 were pooled, serum adiponectin showed positive correlation with progesterone (r = 0.353; p = 0.022) and HDL‐C (r = 0.307; p = 0.048), and negative with insulin (r = ?0.429; p = 0.005), HOMA (r = ?0.446; p = 0.003) and BChE (r = ?0.522; p < 0.001). Ghrelin showed negative correlation with estradiol (r = ?0.701; p = 0.004). BChE was negatively correlated with estradiol (r = ?0.441; p = 0.018) and glucose (r = ?0.343; p = 0.028), and positively with insulin (r = 0.460; p = 0.003) and HOMA (r = 0.505; p < 0.001). In conclusion, changes in metabolic biomarkers occur in bitches after LH peak, characterized by increased lipids (total cholesterol, HDL cholesterol and LDL cholesterol) without changes in BChE activity, and increased adiponectin and ghrelin concentrations, without significant changes in glucose and insulin. 相似文献
129.
Robert McCorkell Katherine Wynne-Edwards Jayson Galbraith Al Schaefer Nigel Caulkett Soren Boysen Ed Pajor The UCVM Class of 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(8):769-774
Ranched bison are typically less acclimated to handling than are domesticated livestock, suggesting that they might be more vulnerable to handling and transportation stressors. Grain-finished bison were slaughtered on-farm (n = 11), or held for 48 h, transported to a research abattoir, held in lairage for 18 h, and then slaughtered (n = 11). An additional group (n = 10) was sampled at a conventional fixed location abattoir. Measures included serum cortisol and corticosterone concentrations during on-farm handling and exsanguination, serum glucose, creatinine phosphokinase (CPK), aspartate aminotransferase (AST), and trim losses. Transport was associated with an increase in trim loss. On-farm, glucose was elevated, CPK was positively associated with handling order over 12 h, and corticosterone concentration, although lower than cortisol concentration, showed a greater response to prolonged disturbance. With appropriate on-farm handling facilities, the use of on-farm slaughter and mobile abattoir could avoid muscle damage and trim losses, and mitigate injuries sustained during handling and transport of bison. 相似文献
130.
N. Schaefer 《African Zoology》2013,48(2):309-326
Growth was calculated for the world’s smallest tor toise species, Homopus signatus signatus, by compar ing body size data gathered in spring 2000, 2001 and 2002. Sexual differences could not be identified, but mean growth was significantly lower in 2000/01 than in 2001/02, possibly due to higher winter rainfall preceding the second period. Variation in growth rates was highest in juveniles. Growth decreased with increasing straight carapace length, resulting in a preliminary estimate of 11 years for females to reach sexual maturity. 相似文献