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521.
Kee-Pyo Kim Cui Li Daria Bunina Hyun-Woo Jeong Julia Ghelman Juyong Yoon Borami Shin Hongryeol Park Dong Wook Han Judith B. Zaugg Johnny Kim Tanja Kuhlmann Ralf H. Adams Kyung-Min Noh Steven A. Goldman Hans R. Schöler 《Cell Stem Cell》2021,28(7):1291-1306.e10
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522.
Western societies can reduce avoidable mortality and morbidity by better understanding the relationship between obesity and chronic disease. This paper examines the empirical association between obesity and the incidence of heart disease, diabetes, hypertension, and elevated cholesterol. We analyze a broadly representative Spanish dataset, the 1999 Survey on Disabilities, Impairments and Health Status, using a health production theoretical framework together with a seemingly unrelated probit model approach that controls for unobserved heterogeneity and endogeneity. Its findings provide evidence of a positive and significant, although specification-dependent, association between obesity and the prevalence of all chronic illness examined. 相似文献
523.
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525.
The proposal that EPR Signal II in spinach chloroplasts is due to a plastoquinone cation radical (O'Malley, P.J. and Babcock, G.T. (1983) Biophys. J. 41, 315a) has been investigated in further detail. The similarity in spectral shape between Signal II and the 2-methyl-5-isopropylhydroquinone cation radical is shown to arise from hyperfine coupling to one methyl group for both radicals. A well-resolved four line EPR spectrum of approximate relative intensity 1:3:3:1 for membrane orientation parallel and perpendicular to the applied magnetic field direction also indicates that the partially resolved structure of Signal II is due to hyperfine interaction with one methyl group, i.e., the 2-CH3 group of the plastoquinone cation radical. The ENDOR band observed for this coupling is similar to that observed for methyl group bands of model quinone radicals. The principal hyperfine tensor values obtained for the methyl group interactions are A⊥ = 27.2 MHz and . The large isotropic coupling value (28.6 MHz) of the plastoquinone cation radical's 2-methyl group in vivo indicates that the antisymmetric orbital is the sole contributor to the spin-density distribution of Signal II. The orientation data also suggest that the plastoquinone cation radical is oriented such that the C-CH3 bond direction, and hence the aromatic ring plane, lies perpendicular to the membrane plane. 相似文献
526.
Toshiyuki Furutani Masakatsu Furui Hiroshi Ooshima Jyoji Kato 《Enzyme and microbial technology》1996,19(8)
Lipase-catalyzed
-acylations of β-amino alcohols such as ethanolamine and
-serine were investigated. To prepare
-acyl derivatives by taking advantage of the acyl migration, we first carried out a screening of suitable enzymes for the desired reaction. As a result, we found a higher activity for
-acylation with Lipase
L. This lipase had higher hydrolytic activity for the o-acyl compound but not the
-acyl compound. The observation shows that
-acylation results from the esterification and successive acyl migration into the amino group. Using Lipase
L, we then investigated the
-acylation of ethanolamine or
-serine with fatty acids as acyl donors. The reaction parameters for the
-acylation were clarified. 相似文献
527.
Amanda Grobe 《应用植被学》2023,26(3):e12744
Aims
The cultivation of Sphagnum mosses in paludiculture has high potential for the use of formerly drained peatlands under wet conditions. The aim of this study was to evaluate the plant species composition and vegetation structure of Sphagnum cultivation sites in comparison with near-natural donor sites and rewetted sites without Sphagnum introduction.Location
Central Europe, northwest Germany close to the Dutch–German border.Methods
The treatments (rewetting with and without Sphagnum introduction) and a near-natural donor as a reference were each studied at three different sites. At each site, bryophyte and vascular plant species composition as well as parameters of vegetation structure were sampled in 40 randomly positioned plots of 25 cm × 25 cm.Results
In addition to the highly frequent Sphagnum, several further plant species typical of bogs were introduced. At two cultivation sites, the species composition showed a high degree of similarity to the near-natural donor sites, whereas the third site was more similar to the rewetted sites without the introduction of Sphagnum biomass. Rewetted sites were species-poor in comparison with all other sites. Apart from a high cover of Sphagnum, the vegetation structure at the cultivation sites differed significantly from the near-natural donor sites.Conclusions
Sphagnum cultivation sites can be used to grow donor material for peatland restoration and contribute to species conservation by providing substitute habitat for bog-typical and threatened plant species. 相似文献528.
《Theriogenology》2016,85(9):1587-1593.e4
The relationship between the quality of cool-shipped stallion semen and fertility has not been adequately described. This study evaluated sperm quality of cool-shipped semen from 459 ejaculates (N = 130 stallions) that were used for insemination of 196 embryo donor mares (n = 496 estrous cycles). Embryo recovery rate (ERR; %) increased, as all sperm measures (e.g., motility, viability, DNA quality, morphology, concentration, and total number) increased. Threshold values are reported for each sperm quality measure (e.g., total sperm motility ≥ 65%) that separate two ERR groups (e.g., average: ∼50% ERR; high: ∼65% ERR). 相似文献
529.
Water is clearly important for the functioning of Photosystem II (PSII). Apart from being the very substrate that needs to be transported in this water oxidation enzyme, water is also vital for the transport of protons to and from the catalytic center as well as other important co-factors and key residues in the enzyme. The latest crystal structural data of PSII have enabled detailed analyses of the location and possible function of water molecules in the enzyme. Significant progress has also been made recently in the investigation of channels and pathways through the protein complex. Through these studies, the mechanistic significance of water for PSII is becoming increasingly clear. An overview and discussion of key aspects of the current research on water in PSII is presented here. The role of water in three other systems (aquaporin, bacteriorhodopsin and cytochrome P450) is also outlined to illustrate further points concerning the central significance that water can have, and potential applications of these ideas for continued research on PSII. It is advocated that water be seen as an integral part of the protein and far from a mere solvent. 相似文献
530.
Existing empirical research often do not explain which concepts about genetics underlie the assumption that genetic information is deemed important for donor-conceived offspring. This study focused on how donor-conceived individuals following anonymous sperm donation give meaning to and make sense of genes and genetics. Analysis is based on focus groups and interviews with adult donor-conceived offspring. Findings suggest that genes are part of their specific context of being donor-conceived but also play a role in daily life. Genes make sense on an individual level and a relational level, both on parent-child as sibling-level. On an individual level they were perceived as (1) a biological starting package, (2) their own unique combination and (3) as a reference point. On a relational level, genes were seen as (1) “person-al”, (2) connecting and (3) locating individuals. This information is essential for those supporting/counseling donor conceived offspring and families as well as for policy-members. 相似文献