Climate Change During the Last Deglaciation in Antarctica   总被引：1，自引：0，他引：1  

PA Mayewski  MS Twickler  SI Whitlow  LD Meeker  Q Yang  J Thomas  K Kreutz  PM Grootes  DL Morse  EJ Steig  ED Waddington  ES Saltzman  P Whung  KC Taylor 《Science (New York, N.Y.)》1996,272(5268):1636-1638

Greenland ice core records provide clear evidence of rapid changes in climate in a variety of climate indicators. In this work, rapid climate change events in the Northern and Southern hemispheres are compared on the basis of an examination of changes in atmospheric circulation developed from two ice cores. High-resolution glaciochemical series, covering the period 10,000 to 16,000 years ago, from a central Greenland ice core and a new site in east Antarctica display similar variability. These findings suggest that rapid climate change events occur more frequently in Antarctica than previously demonstrated.  相似文献   

Targeting malaria virulence and remodeling proteins to the host erythrocyte     

Marti M  Good RT  Rug M  Knuepfer E  Cowman AF 《Science (New York, N.Y.)》2004,306(5703):1930-1933

To establish infection in the host, malaria parasites export remodeling and virulence proteins into the erythrocyte. These proteins can traverse a series of membranes, including the parasite membrane, the parasitophorous vacuole membrane, and the erythrocyte membrane. We show that a conserved pentameric sequence plays a central role in protein export into the host cell and predict the exported proteome in Plasmodium falciparum. We identified 400 putative erythrocyte-targeted proteins corresponding to approximately 8% of all predicted genes, with 225 virulence proteins and a further 160 proteins likely to be involved in remodeling of the host erythrocyte. The conservation of this signal across Plasmodium species has implications for the development of new antimalarials.  相似文献   

"The big trouble with scientific writing . . ."     

Good RH 《Science (New York, N.Y.)》1967,157(3795):1374-1376

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Nucleolar clustering of dispersed tRNA genes     

Thompson M  Haeusler RA  Good PD  Engelke DR 《Science (New York, N.Y.)》2003,302(5649):1399-1401

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Rapid Variations in Atmospheric Methane Concentration During the Past 110,000 Years     

EJ Brook  T Sowers  J Orchardo 《Science (New York, N.Y.)》1996,273(5278):1087-1091

A methane record from the GISP2 ice core reveals that millennial-scale variations in atmospheric methane concentration characterized much of the past 110,00 years. As previously observed in a shorter record from central Greenland, abrupt concentration shifts of about 50 to 300 parts per billion by volume were coeval with most of the interstadial warming events (better known as Dansgaard-Oeschger events) recorded in the GISP2 ice core throughout the last glacial period. The magnitude of the rapid concentration shifts varied on a longer time scale in a manner consistent with variations in Northern Hemisphere summer insolation, which suggests that insolation may have modulated the effects of interstadial climate change on the terrestrial biosphere.  相似文献   

Impact of the national full herd depopulation policy on the recurrence of bovine tuberculosis in Irish herds, 2003 to 2005     

Good M  Clegg TA  Duignan A  More SJ 《The Veterinary record》2011,169(22):581

This study evaluated the impact of the Irish herd bovine tuberculosis (bTB) depopulation policy (depopulation, disinfection, contiguous testing and local badger removal where implicated) on the recurrence of bTB infection, by comparing the future risk in restocked herds following depopulation for either bTB or bovine spongiform encephalopathy (BSE) during 2003 to 2005. Each herd was assigned a 'previous bTB risk', based on bTB history during the five years before depopulation. Future bTB risk was estimated, using a multivariable Cox proportional hazard model for time-to-breakdown for each study herd, to identify risk factors associated with bTB. Future bTB risk varied significantly by reason for depopulation and previous bTB risk. Herds depopulated for bTB (by definition, at high bTB risk) were not significantly different from BSE herds with no or a low previous bTB risk. BSE herds with a high previous bTB risk were found to be at significantly greater future bTB risk. Herd bTB depopulation measures, as currently applied in Ireland, are shown to be effective in enabling herds to attain and retain bTB freedom following restocking. Based on the data presented, and consistent with current knowledge of the bTB epidemiology, local badger removal contributes to efforts to limit recurrence of bTB in Ireland.  相似文献   

Risk factors associated with Johne's disease test status in dairy herds in Ireland     

Barrett DJ  Mee JF  Mullowney P  Good M  McGrath G  Clegg T  More SJ 《The Veterinary record》2011,168(15):410

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Histopathological,Immunohistochemical, Lectinhistochemical and Molecular Findings in Spontaneous Bovine Abortions by Campylobacter fetus     

EL Morrell  CG Barbeito  CA Odeón  EJ Gimeno  CM Campero 《Reproduction in domestic animals》2011,46(2):309-315

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Health and metabolic responses of young calves housed at -30 degrees C to -8 degrees C.   总被引：2，自引：1，他引：1       下载免费PDF全文

R E Rawson  H E Dziuk  A L Good  J F Anderson  D W Bates  G R Ruth    R C Serfass 《Canadian journal of veterinary research》1989,53(3):268-274

Newborn, male, Holstein calves, were continuously housed for three weeks in calf hutches at 17 degrees C or in a thermal environment which varied rhythmically on a daily basis either between -20 degrees C and -8 degrees C (experiment A) or between -30 degrees C and -18 degrees C (experiment B). Compared to warm-housed calves, cold-housed calves in experiment A had metabolic rates which were significantly higher (p less than 0.001) in a standing position but which were not significantly different (p less than 0.05) in a recumbent position. Recumbent and standing cold-housed calves in experiment B had an increased (p less than 0.05) metabolic rate compared to warm-housed controls. Heat loss was less (p less than 0.05) for recumbent cold-housed calves in experiment B than for standing calves in a thermoneutral environment. Localized subcutaneous hemorrhages of hindlimbs were a consistent necropsy finding among all cold-housed calves. Average daily gains of cold-housed calves were not significantly different from warm-housed controls. Clinical, physiological and pathological findings indicated that cold treatments used in the present study did not cause serious harm to calves. It was concluded that calves housed in properly managed hutches are remarkably cold tolerant.  相似文献   

Follicle Wave Growth in Cattle   总被引：1，自引：0，他引：1  

M Mihm  MA Crowe  PG Knight  EJ Austin 《Reproduction in domestic animals》2002,37(4):191-200

Ovarian follicle growth in cattle culminates in the selection of a single dominant follicle which attains the ability for final maturation and ovulation once or twice during the luteal phase and at the end of the oestrous cycle, as well as during other reproductive states. This review will describe in detail the first follicle wave of the cycle leading to selection of the first wave dominant follicle, indicating the specific gonadotrophin dependencies of cohort and dominant follicles, and relating follicle fate to steroidogenesis. As a differential gonadotrophin response of growing antral follicles during the follies‐stimulating hormone (FSH) decline may determine which follicle becomes selected, first wave follicles are also characterized in relation to intrafollicular growth factors, which may modify the gonadotrophin response, such as inhibins and members of the insulin‐like growth factor (IGF) family. Subsequently, the follicular control of the transient FSH rise and decline so crucial to dominant follicle selection will be discussed. It is concluded that successful hormonal manipulation of follicle wave growth and dominant follicle selection will depend on our detailed understanding of the gonadotrophin requirements of differentiating wave follicles.  相似文献