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Sources and significance of variation in basal,summit and maximal metabolic rates in birds

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Current Zoology 2010年第6期56卷 741-758页

作者： Andrew E. MCKECHNIE david l. SWANSON DST/NRF Centre of Excellence at the Percy FitzPatrick Institute Department of Zoology and EntomologyUniversity of Pretoria Department of Biology University of South Dakota

The rates at which birds use energy may have profound effects on fitness, thereby influencing physiology, behavior, ecology and evolution. Comparisons of standardized metabolic rates （e.g., lower and upper limits of metabolic power output） present a method for elucidating the effects of ecological and evolutionary factors on the interface between physiology and life history in birds. In this paper we review variation in avian metabolic rates [basal metabolic rate （BMR; minimum normothermic metabolic rate）, summit metabolic rate （Msum; maximal thermoregulatory metabolic rate）, and maximal metabolic rate （MMR; maximal exercise metabolic rate）], the factors associated with this variation, the evidence for functional links between these metabolic traits, and the ecological and evolutionary significance of avian metabolic diversity. Both lower and upper limits to metabolic power production are phenotypically flexible traits, and vary in association with numerous ecological and evolutionary factors. For both inter- and intraspecific comparisons, lower and upper limits to metabolic power production are generally upregulated in response to energetically demanding conditions and downregulated when energetic demands are relaxed, or under conditions of energetic scarcity. Positive correlations have been documented between BMR, Msum and MMR in some, but not all studies on birds, providing partial support for the idea of a functional link between lower and upper limits to metabolic power production, but more intraspecific studies are needed to determine the robustness of this conclusion. Correlations between BMR and field metabolic rate （or daily energy expenditure） in birds are variable, suggesting that the linkage between these traits is subject to behavioral adjustment, and studies of the relationship between field and maximal metabolic rates are lacking. Our understanding of avian metabolic diversity would benefit from future studies of：（1） the functional and mechanistic li

关键词： Phenotypic flexibility Reaction norms Basal metabolic rate Maximal metabolic rate Birds

Turning the corner from observation to intervention in human genetics

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Journal of Genetics and Genomics 2018年第2期45卷 57-59页

作者： david l.Nelson Department of Molecular and Human Genetics Baylor College of Medicine Jan and Dan Duncan Neurological Research Institute

In the early 1990s,shortly after we identified the genetic defect in FMR1 that results in fragile X syndrome（Verkerk et al.,1991）,I attended a conference sponsored by the US National Fragile X *** biannual meeting m... 详细信息

关键词： Turning the corner from observation to intervention in human genetics

Peritonectomy HIPEC-contemporary results,indications

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Chinese Journal of Cancer Research 2013年第4期25卷 373-374页

作者： david l.Morris UNSW Department of Surgery St George Hospital

Paul Sugarbaker＇s procedural description in this paper （1）comes from the pioneer and master of this area. His original description of peritoneal cancer index （PCI） and cytoreduction score （CC） is also fundament... 详细信息

关键词： PCI Peritonectomy HIPEC-contemporary results,indications

Atomic-scale engineering of oxide interfaces yields a new family of synthetic magnetic structures

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Science Bulletin 2017年第17期62卷 1169-1170页

作者： david l.Cortie Xiaolin Wang ARC Centre of Excellence in Future low-Energy Electronics Technologies University of WollongongNorth WoUongongNSW 2522Australia The Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of Wollongong North WollongongNSW 2522Australia

A grand challenge in the field of magnetism is to find material systems that exhibit spin structures ranging from simple ferromagnets to exquisite non-collinear *** bulk three-dimensional(3D)materials,however,the magnetic exchange interactions are constrained by the crystal symmetry and quantum chemistry,making it challenging to adjust the intrinsic magnetic structure.A

关键词：铁磁性工程师原子尺度合成结构族氧化物交换相互作用界面

Probability to retrieve testicular spermatozoa in azoospermic patients

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Asian Journal of Andrology 2000年第3期2卷 199-205页

作者： H.-J.Glanden l.-C.horn W.Dorschner U.Paasch J.Kratzsch Department of Dermatology/Andrology Unit Department of Dermatology Department of PathologyDepartment of Dermatology Department of UrologyDepartment of Dermatology/Andrology UnitDepartment of Clinical Chemistry and Pathological Biochemistry University of Leipzig D-04103 Leipzig Germany

Aim: The degree of probability to retrieve spermatozoa from testicular tissue for intracytoplasmic sperm injection intooocytes is of interest for counselling of infertility patients. We investigated the relation of sperm retrieval to clinical dataand histological pattern in testicular biopsies from azoospermic patients. Methods: In 264 testicular biopsies from142 azoospermic patients, the testicular tissue was shredded to separate the spermatozoa, histological semi-thin sec-tions of which were then evaluated using Johnsen score. Results: The retrieval of spermatozoa correlated signifi-cantly (P lar volume (r = 0.49), the FSH concentration ( r = -0.66), the maximum score(r = 0.85) and the mean Johnsen score (r = 0.81). In the multivariate regression analysis the successful testicularsperm extraction showed the closest relationship to the maximum score. The testicular volume correlated significantlywith the mean Johnsen score ( r = 0.64, P l serum FSH concentration mainly with the maxi-mum score ( r = -0.77; P ly lower Johnsenscore compared to the patients who did not have any testicular disease in the past (3.7 ± 2.4 vs. 5.9 ± 2. 5; P lusion: In a limited range, the testicular volume and the FSH concentration in serum were related to theJohnsen score which correlated significantly with the sperm retrieval. The successful sperm retrieval can be expected inall azoospermic patients irrespective of the results of clinical examination. However, the probability of retrieval of sper-matozoa decreased significantly in patients with a FSH level > 18 U/l, tesficular volume l, mean Johnsen score< 5, and maximum Johnsen score < 7.

关键词： sperm extraction testicular histology azoospermia male infertility follicle stimulating hormone

The skeleton gets a （reproductive） life

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Asian Journal of Andrology 2011年第5期13卷 651-652页

作者： Charles M Allan david l Handelsman ANZAC Research Institute Concord Hospital Universityof Sydney Sydney NSW 2139 Australia

To most well-informed scientists who do not work on bone, the idea that bones determine anything other than your posture and location for the miseries of arthritis would come as quite a surprise. It would be like imagining that the walls of our home played something more than a passive role in the complexities of the lives conducted within. Yet something precisely as radical as that is what Karsenty and his colleagues boldly imagined,1 and then provocatively established in a series of studies over the past decade.20steocalcin （OCN） is a vitamin K- dependent peptide hormone secreted by the bone-formine osteoblasts.

关键词： reproductive david J Handelsman

Kri1l: a novel gene that links defective ribosome biogenesis to impaired hematopoiesis through excessive autophagy

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Science Bulletin 2015年第17期60卷 1547-1548页

作者： Yong Zhang david l.Wiest Blood Cell Development and Function Program Fox Chase Cancer Center Philadelphia

The ribosome is an ancient and conserved molecular machine responsible for translating mRNA into protein in all known organisms. The eukaryotic ribosome is com- posed of - 80 ribosomal proteins （RPs） and four ribosomal RNAs （rRNAs）. These RNA and protein components are assembled within the nucleolus into the small 40S and large 60S subunits of the ribosome, through a process termed ribosome biogenesis. Ribosome biogenesis is a highly orchestrated and carefully controlled process that requires - 150 associated proteins and 70 small nucleolar RNAs （snoRNAs）, which assist in prerRNA transcription and maturation, ribosome component assembly, and trafficking to the cytosol. Defects in ribosome biogenesis resulting from mutations in biogenesis cofactors, or in ribosomal structural components themselves, cause a collection of human diseases termed ＂ribosomopathies＂.

关键词： Ribosome biogenesis Hematopoietic stem cell Autophagy Ribosomopathy Zebrafish

Seasonal metabolic flexibility is correlated with microclimate variation in horned larks and house sparrows

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Current Zoology 2022年第2期68卷 199-210页

作者： Paige OBOIKOVITZ david l.SWANSON Department of Biology University of South DakotaVermillionSD 57069USA

Maximum and minimum metabolic rates in birds are flexible traits and such flexibility can be advantageous in variable *** climatic variability hypothesis(CVH)posits that more variable climates should result in greater metabolic flexibility for geographically distinct *** the CVH applies to sympatric species occupying microclimates differing in variability is *** of open habitats are likely more variable than those of sheltered *** the CVH extends to microclimates,we expect birds from open habitats to show greater flexibility than those from sheltered *** test this extension of the CVH,we compared seasonal variation in microclimates and metabolic rates for sympatric horned larks Eremophila alpestris,which occupy open habitats,and house sparrows Passer domesticus,which occupy sheltered *** measured operative temperature(T_(e′) an integrative measure of the thermal environment),summit metabolic rate(M_(sum′) maximal cold-induced metabolic rate),and basal metabolic rate(BMR,minimal maintenance metabolic rate)in summer and *** both winter and summer,daily minimum Te was similar between open and sheltered habitats but maximum Te was higher for open *** microclimates,however,were colder for open than for sheltered habitats after accounting for convective *** species increased M_(sum) in winter,but seasonal M_(sum) flexibility was greater for larks(43%)than for sparrows(31%).Winter increases in BMR were 92.5% and 11% for larks and sparrows,respectively,with only the former attaining statistical ***,species*season interactions in general linear models for whole-organism metabolic rates were significant for BMR and showed a similar,although not significant,pattern for M_(sum),with greater seasonal metabolic flexibility in horned larks than in house *** results suggest that extending the CVH to sympatric bird species occupying different microclimates

关键词： climatic variability hypothesis Eremophila alpestris metabolic flexibility metabolic rates microclimates Passer domesticus

A New Chinese Anurognathid Pterosaur and the Evolution of Pterosaurian Tail lengths

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Acta Geologica Sinica(English Edition) 2012年第6期86卷 1317-1325页

作者： lÜ Junchang david W.E.HONE Institute of Geology Chinese Academy of Geological Sciences School of Biology and Environmental Sciences University College Dublin

A new anurognathid pterosaur specimen from the Middle Jurassic Tiaojishan Formation of Qinglong, northern Hebie Province is described. The new specimen is referred to Dendrorhynchoides, based on the general morphology of the skeleton, but it represents a new species, named here as Dendrorhynchoides mutoudengensis sp. nov.. It is characterized by the presence of short, robust and straight teeth, and bearing wing metacarpal approximately 40% of the length of humerus. The new specimen provides further osteological information for anurognathid pterosaurs, especially the presence of a relatively elongate tail.

关键词： Pterosauria rhamphothynchoids anurognathid Dendrorhynchoides mutoudengensis,pterodactyloids tail evolution.