Cytochalasin B: effects on microfilaments and movement of melanin granules within melanocytes   总被引：12，自引：0，他引：12  

J McGuire  G Moellmann 《Science (New York, N.Y.)》1972,175(22):642-644

The intracellular translocation of melanin granules within both epidermal and dermal melanocytes of Rana pipiens is influenced by cytochalasin B. Cytochalasin B prevents dispersion of pigment granules by melanocytestimulating hormone (MSH) and causes centripetal movement of pigment granules that have been dispersed by MSH. Microfilaments are abundant in the dendritic processes of epidermal melanocytes in which pigment granules have been dispersed by MSH. Microfilaments are dramatically reduced in number in the processes of melanocytes that have been lightened by cytochalasin B. These observations suggest that microfilaments mediate dispersion of pigment granules.  相似文献   

Prevalence of antibodies to herpesvirus types 1 and 2, arteritis and infectious anemia viral antigens in equine serum   总被引：2，自引：0，他引：2  

T C McGuire  T B Crawford  J B Henson 《American journal of veterinary research》1974,35(2):181-185

  相似文献   

Comparison of palatability traits of beef produced by young bulls and steers     

J O Reagan  Z L Carpenter  G C Smith  G T King 《Journal of animal science》1971,32(4):641-646

  相似文献   

Viral-induced hemolysis in equine infectious anemia   总被引：4，自引：0，他引：4  

T C McGuire  J B Henson  S E Quist 《American journal of veterinary research》1969,30(12):2091-2097

  相似文献   

Immunity in equine infectious anemia     

J B Henson  J R Gorham  K Kobayashi  T C McGuire 《Journal of the American Veterinary Medical Association》1969,155(2):336-343

  相似文献   

Inoculation of two genotypes of Hemobartonella felis (California and Ohio variants) to induce infection in cats and the response to treatment with azithromycin     

Westfall DS  Jensen WA  Reagan WJ  Radecki SV  Lappin MR 《American journal of veterinary research》2001,62(5):687-691

OBJECTIVES: To describe clinical and laboratory findings associated with cats experimentally infected by inoculation with the 2 recognized genotypes of Hemobartonella felis (small variant, Hfsm; large variant, Hflg) and to determine the response of cats to treatment with azithromycin. ANIMALS: 18 young adult domestic shorthair cats of both sexes. PROCEDURES: Cats were inoculated with H felis and monitored weekly, using CBC counts and a polymerase chain reaction (PCR) designed to detect both genetic variants of H felis. Beginning 26 days after inoculation, 11 cats were administered azithromycin (15 mg/kg of body weight, PO, q 12 h, for 7 days). RESULTS: Inoculation resulted in coinfection with Hflg and Hfsm, and both variants were detected by PCR. Clinical abnormalities and anemia were most severe in Hflg- and dual-infected cats. Results of PCR and CBC were positive for H felis in 112/112 (100%) and 42/112 (37.5%), respectively, samples collected after inoculation. Administration of azithromycin had little effect on clinical variables, including anemia. All cats, regardless of treatment with azithromycin, had positive results for the PCR at the end of the study period. CONCLUSIONS AND CLINICAL RELEVANCE: In these cats, Hflg was more pathogenic than Hfsm, and coinfection with both variants was detected. Results of the PCR were superior to results of CBC for detecting infection with H felis. Azithromycin administered at the dose and duration reported here was not efficacious for the treatment of cats with hemobartonellosis.  相似文献   

Consumer impressions of Tender Select beef.   总被引：14，自引：0，他引：14  

S D Shackelford  T L Wheeler  M K Meade  J O Reagan  B L Byrnes  M Koohmaraie 《Journal of animal science》2001,79(10):2605-2614

  相似文献   

Energetic and kinematic consequences of weighting the distal limb     

Wickler SJ  Hoyt DF  Clayton HM  Mullineaux DR  Cogger EA  Sandoval E  McGuire R  Lopez C 《Equine veterinary journal》2004,36(8):772-777

REASON FOR PERFORMING STUDY: It is well known that adding a load to a horse's back increases its energetic costs of locomotion, but the magnitude of increase obtained by loading the most distal portion of limb has not been measured. OBJECTIVES: To measure oxygen consumption in horses with mass added to the back and hooves. Because such mass distribution alters inertial parameters of the limbs, kinematic measurements were made to quantify the magnitude of change in limb movement. METHODS: Steady-state oxygen consumption was measured in 6 horses with a load of 2.4 kg. The load was either carried on the back or distributed equally between the 4 limbs. Modified bell boots kept the mass at the level of P3. Horses trotted on a treadmill at speeds ranging from 2 to 5 m/sec (in 0.5 m/sec increments). High-speed (250 Hz) digital images were recorded in a sagittal plane and the positions of retroreflective markers located on standard positions on the limbs were digitised for kinematic analysis. RESULTS: Loading of the distal limbs produced a 6.7% increase in metabolic rate, an order of magnitude higher than when the mass was added over the back. Although the stride period was 2% longer in horses with loads on the distal limbs, time of contact and duty factor were not different. Distal limb loading increased the range of motion in hind- but not forelimbs. CONCLUSIONS: The costs of swinging the limbs in the horse are considerable and the addition of weights to the distal limb can have a profound effect on not only the energetics of locomotion but also the kinematics, at least in the hindlimb. POTENTIAL RELEVANCE: The use of weighted shoes, intended to increase animation of the gait, increases the metabolic effort of performance horses a disproportionate amount. The additional mass also increases the joint range of motion and, potentially, the likelihood of injury.  相似文献   

National Beef Tenderness Survey-1998     

Brooks JC  Belew JB  Griffin DB  Gwartney BL  Hale DS  Henning WR  Johnson DD  Morgan JB  Parrish FC  Reagan JO  Savell JW 《Journal of animal science》2000,78(7):1852-1860

Fifty-six retail stores representing 15 retail chains and 14 foodservice facilities in eight U.S. cities were sampled to determine the tenderness of beef steaks at retail and foodservice levels based on Warner-Bratzler shear (WBS) values and consumer evaluation panels. Retail consumer panels were conducted at five universities. Each retail and foodservice steak was evaluated using 10-point scales. Steaks were divided into the following quality groups for statistical analysis: Prime, Top Choice, Choice, Select, and Lean or No Roll. Quality group had no effect on WBS values of retail clod, chuck roll, top round, bottom round, eye of round, top loin, top sirloin, or ribeye steaks but did (P < .05) affect values for the T-bone/porterhouse. The percentages of retail top round, eye of round, and bottom round steaks with a WBS force > 3.9 kg were 39.6, 55.9, and 68.0, respectively. Foodservice ribeye, top loin, and top sirloin steaks had WBS values less than 3.4 kg for all quality groups, with Prime ribeye steaks having lower (P < .05) WBS values than ribeyes from the other quality groups. With the exception of the retail ribeye steak, quality group did not affect consumer sensory ratings of retail and foodservice steaks. Average postfabrication aging times were 32 d for foodservice subprimals and 19 d for retail cut subprimals. These data indicate that improvements in the tenderness of retail cuts from the round are needed. Finally, quality group had little or no effect on consumer sensory evaluations and WBS values of retail and foodservice steaks used in this study.  相似文献   

Xylem and soil CO2 fluxes in a Quercus pyrenaica Willd. coppice: root respiration increases with clonal size     

Roberto Salomón  María Valbuena-Carabaña  Jesús Rodríguez-Calcerrada  Doug Aubrey  MaryAnne McGuire  Robert Teskey  Luis Gil  Inés González-Doncel 《Annals of Forest Science》2015,72(8):1065-1078

  相似文献