THE OXYGEN CONSUMPTION OF NERVE DURING ACTIVITY     

Gerard RW 《Science (New York, N.Y.)》1930,72(1860):195-196

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Paucity of genes on the Drosophila X chromosome showing male-biased expression     

Parisi M  Nuttall R  Naiman D  Bouffard G  Malley J  Andrews J  Eastman S  Oliver B 《Science (New York, N.Y.)》2003,299(5607):697-700

Sex chromosomes are primary determinants of sexual dimorphism in many organisms. These chromosomes are thought to arise via the divergence of an ancestral autosome pair and are almost certainly influenced by differing selection in males and females. Exploring how sex chromosomes differ from autosomes is highly amenable to genomic analysis. We examined global gene expression in Drosophila melanogaster and report a dramatic underrepresentation of X-chromosome genes showing high relative expression in males. Using comparative genomics, we find that these same X-chromosome genes are exceptionally poorly conserved in the mosquito Anopheles gambiae. These data indicate that the X chromosome is a disfavored location for genes selectively expressed in males.  相似文献   

A critical role for eosinophils in allergic airways remodeling     

Humbles AA  Lloyd CM  McMillan SJ  Friend DS  Xanthou G  McKenna EE  Ghiran S  Gerard NP  Yu C  Orkin SH  Gerard C 《Science (New York, N.Y.)》2004,305(5691):1776-1779

Features of chronic asthma include airway hyperresponsiveness, inflammatory infiltrates, and structural changes in the airways, termed remodeling. The contribution of eosinophils, cells associated with asthma and allergy, remains to be established. We show that in mice with a total ablation of the eosinophil lineage, increases in airway hyperresponsiveness and mucus secretion were similar to those observed in wild-type mice, but eosinophil-deficient mice were significantly protected from peribronchiolar collagen deposition and increases in airway smooth muscle. These data suggest that eosinophils contribute substantially to airway remodeling but are not obligatory for allergen-induced lung dysfunction, and support an important role for eosinophil-targeted therapies in chronic asthma.  相似文献   

Use of time-activity budgets to measure early progress of a social attraction restoration project     

Peter J. Kappes  Gerard J. McChesney  Michael W. Parker  Harry R. Carter  Stephen W. Kress  Richard T. Golightly 《Biological conservation》2011,(1):620-626

Social attraction is a useful technique for re-establishing or relocating waterbird colonies and other species groups. However, little information exists regarding how newly attending individuals behave when the social environment is influenced predominantly by artificial stimuli. To help assess early progress of colony re-establishment, we compared time-activity budgets of common murres (Uria aalge) at a social attraction site (Devil’s Slide Rock; DSR) in central California with two nearby reference colonies during the first 3 years (1996–1998) of efforts. Murres at all colonies spent over 95% of their time engaged in resting, comfort, courtship, and alert activities during the pre-breeding period and over 88% of their time in similar activities during the breeding period. Although patterns were similar overall, comparisons of pooled and year-specific time budget data revealed significant differences between all three colonies, especially during pre-breeding. Murres at DSR typically engaged in comfort behaviors less frequently and in alert and courtship behaviors more frequently than reference colonies. Differences likely were due to recent re-establishment, including lower bird densities and higher proportions of non-breeders and first-time breeders at DSR, along with other factors such as disturbance. Results indicate that newly attracted birds at DSR behaved “normally” even though the social environment was influenced predominantly by artificial stimuli. Furthermore, re-established breeding in the first year of efforts, subsequent colony growth, and high productivity reflected successful restoration efforts. Thus, time-activity budgets can provide important measures of early progress of social attraction efforts and as such can be used to inform adaptive management decisions.  相似文献   

The impact of environmental change on the intensity and spatial pattern of water erosion in a semi-arid mountainous Andean environment     

Veerle Vanacker  Gerard Govers  Jean Poesen  Jozef Deckers  Gerd Dercon  George Loaiza 《CATENA》2003,51(3-4):329-347

Aerial photographs taken in 1976 and 1989 and a field survey in 1999 showed that land use in a 900-ha catchment in the southern part of the Ecuadorian Andes is highly dynamic. Over 23 years, ca. 83 ha of arable land was abandoned and ca. 70 ha was taken into agricultural production. Changes in land use were not spatially homogeneous. Parcels on unstable geologic formations and close to village centres were preferably set-aside. Land taken into cultivation was preferably located on gently sloping areas close to newly built sites and arterial roads. The area with bush vegetation increased by regeneration of natural vegetation on fields set-aside in the late 1970s and early 1980s. There was a complex interaction between water erosion and environmental change in the study area. Land taken into production was levelled for furrow irrigation: this led to a net reduction in the area susceptible to water erosion. However, one quarter of the area affected only by sheet and rill erosion 23 years ago has since become incised by deep gullies. This increase in gully density was related to inadequate construction and management of irrigation infrastructure, rather than to change in vegetation cover and/or soil erodibility caused by agricultural practices. This factor is often overlooked in studies of the effects of environmental change on geomorphologic processes.  相似文献   

Antibacterial Drug Resistance in Aeromonas spp. Isolated from Domestic Goldfish and Koi from California     

Beverly A.  Dixon Gerard  Issvoran 《Journal of the World Aquaculture Society》1993,24(1):102-104

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Growth and Survival of the Australian Red Claw Crayfish Cherax quadricarinatus at Three Densities in Earthen Ponds     

Gerard F.  Pinto David B.  Rouse 《Journal of the World Aquaculture Society》1996,27(2):187-193

Australian red claw crayfish Cherax quadricarinatus were cultured in nine 0.02-ha earthen ponds at densities of l/m², 3/m² and 5/m² for 158 d. Average weight at stocking was 3.2 g. All ponds were provided with a combination of hay and corn silage at a rate of 500 kg/ha per month and a commercial crayfish ration fed at 5%, decreasing to 2% of estimated biomass/d during the growing season. Overall survival rate was 72%, and did not differ among treatments. Final yields and average weights varied significantly with stocking density. Red claw averaged 67 g with an average pond yield of 475 kg/ha at l/m². At 3/m² and 5/m², red claw averaged 48 g and 38 g, respectively, and yielded 1,020 kg/ha and 1,422 kg/ha, respectively.  相似文献   

Analysis of Mammalian Masticatory Mechanisms: Progress and Problems     

Carl  Gans  Fritz de  Vree Gerard C.  Gorniak 《Anatomia, histologia, embryologia》1978,7(3):226-244

Direct measurement of bone movements and muscle activation in mammalian mastication is now possible. Early results indicate that the patterns are quite variable and depart from the stereotyped versions sometimes reported. Most mammals masticate unilaterally; only a few chew simultaneously on both sides. Orbital movements are complex and three-dimensional. While most muscles are active during the reduction phase, it is difficult to define phases by sharp transitions of activity. The fascicles of pinnate muscles differ in fiber architecture and physiology; they tend to function at different times and with distinct mechanical advantages. Interspecific diversity and marked responses to food consistency and size, still preclude generalizations. Improved methods for comparisons among orbits, for correlation of forces and excursions, and automated correlations of movements, forces and electromyograms are beginning to be available and need to be more generallv applied to analysis.  相似文献   

Oral squamous cell carcinoma in a cat     

Teske E  Rutteman GR 《Tijdschrift voor diergeneeskunde》2005,130(24):764-766

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In vitro effects and in vivo efficacy of a novel cyclooxygenase-2 inhibitor in cats with lipopolysaccharide-induced pyrexia     

McCann ME  Rickes EL  Hora DF  Cunningham PK  Zhang D  Brideau C  Black WC  Hickey GJ 《American journal of veterinary research》2005,66(7):1278-1284

OBJECTIVE: To determine cyclooxygenase (COX)-2 selectivity, pharmacokinetic properties, and in vivo efficacy of firocoxib (ML-1,785,713) in cats. ANIMALS: 5 healthy male and 14 healthy female domestic shorthair cats. PROCEDURE: Selectivity of firocoxib for inhibiting COX-2 was determined by comparing the potency for inhibiting COX-1 with that of COX-2 in feline blood. Pharmacokinetic properties were determined after i.v. (2 mg/kg) and oral (3 mg/kg) administration in male cats. In vivo efficacy was evaluated in female cats with lipopolysaccharide (LPS)-induced pyrexia with administration of firocoxib 1 or 14 hours before LPS challenge. RESULTS: Blood concentrations resulting in 50% inhibition of COX-1 and COX-2 activity in vitro were 75 +/- 2 microM and 0.13 +/- 0.03 microM, respectively, and selectivity for inhibiting COX-2 relative to COX-1 was 58. Firocoxib had moderate to high oral bioavailability (54% to 70%), low plasma clearance (4.7 to 5.8 mL/min/kg), and an elimination half-life of 8.7 to 12.2 hours. Firocoxib at doses from 0.75 to 3 mg/kg was efficacious in attenuating fever when administered to cats 1 or 14 hours before LPS challenge. CONCLUSIONS AND CLINICAL RELEVANCE: Firocoxib is a potent COX-2 inhibitor and is the only selective COX-2 inhibitor described for use in cats to date. It is effective in attenuating febrile responses in cats when administered 14 hours before LPS challenge, suggesting it would be suitable for once-a-day dosing. Because selective COX-2 inhibitors have an improved therapeutic index relative to nonselective nonsteroidal anti-inflammatory drugs in humans, firocoxib has the potential to be a safe, effective anti-inflammatory agent for cats.  相似文献