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To compare the effects of time of daily protein supplementation on grazing behavior, forage intake, digesta kinetics, ruminal fermentation, and serum hormones and metabolites, 12 ruminally cannulated Holstein steers (449 and 378 kg average initial and final BW, respectively) were allotted to three groups. Treatments consisted of CON = no supplement, AM = cottonseed meal (.25% of BW) at 0600, and PM = cottonseed meal (.25% of BW) at 1200. Steers grazed a dormant (1.1% N) intermediate wheatgrass (Thinopyrum intermedium Host) pasture. Sampling trials occurred in December, January, and February. Supplementation altered (P = .01) time spent grazing; CON steers grazed approximately 1.5 h longer than supplemented steers. Supplemented steers lost less (P = .02) BW (-40 kg) than CON steers (-75 kg) did. Supplementation did not alter (P greater than .15) forage OM intake; however, total OM intake was greater (P = .01) for supplemented steers (22.3 g/kg of BW) than for CON (18.4 g/kg of BW) steers. Supplementation did not affect (P greater than .15) digesta kinetics. Extent of in situ NDF (96 h) and rate (%/h) of disappearance for supplemented steers was greater (P = .01) than for CON steers. Across all periods, ruminal NH3 N and total VFA concentrations were lower (P = .01) for CON steers than for supplemented steers. Serum insulin (ng/mL) concentration was lower (P = .03) and concentration of serum growth hormone (ng/mL) was higher (P = .02) for CON steers than for supplemented steers. Cottonseed meal supplementation enhanced utilization of intermediate wheatgrass; however, supplementation time had minimal effects on the variables measured.  相似文献   
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The growth factor receptor‐bound protein 14 (Grb14) is a cellular adapter protein belonging to the Grb7 family of proteins. Studies with human and rodent cells have demonstrated that Grb14 acts as a negative regulator of tyrosine kinase receptor signalling through the MAPK and PI3K pathways. In cattle, tyrosine kinase receptors are activated during follicular development but the role of Grb14 in this process has not yet been investigated. Therefore, the aim of the present study was to characterize Grb14 mRNA expression in ovarian somatic cells during follicular growth and deviation in cattle. We found Grb14 mRNA expressed in both granulosa and theca cells derived from follicles at different stages of development (3–5 , 6–8, >8 mm in diameter). The abundance of mRNA for Grb14 was higher in granulosa cells of subordinate compared with those from dominant follicles at days 3 and 4 of the follicular wave (p < 0.05). Further, there was a negative correlation between the abundance of mRNA for Grb14 and P450Arom in granulosa cells (R2 = 0.367; p < 0.05) and between the abundance of mRNA for Grb14 in granulosa cells and concentration of oestradiol in follicular fluid (R2 = 0.545; p < 0.05). In theca cells, the expression of Grb14 mRNA did not differ between dominant and subordinate follicles (p > 0.05). These findings suggest that Grb14 may play a regulatory role in granulosa cells during follicular deviation in cattle.  相似文献   
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Cyclooxygenase (COX) enzymes catalyze the synthesis of prostaglandins and exist as two isoforms, COX-1 and COX-2. COX-2 is a potent inducible mediator of inflammation. COX-2 is also upregulated in several human tumors and in canine squamous cell, renal cell, and transitional cell carcinomas, prostatic adenocarcinoma, and intestinal neoplasia. The purpose of this study was to determine whether COX-2 is expressed in various feline tumors. Results of this study may help determine whether COX-2 is a potential target for therapeutic and preventive strategies in cats. Immunohistochemical studies were performed on paraffin-embedded tissues using the amplified streptavidin-biotin-horseradish peroxidase system. COX-2 was found in 7 of 19 (37%) feline transitional cell carcinomas and in 2 of 21 (9%) feline oral squamous cell carcinomas. No COX-2 immunoreactivity was detected in cutaneous squamous cell carcinomas (6), adenocarcinomas (nine mammary, eight pulmonary, seven intestinal), lymphomas (six nasal, six intestinal), or 10 vaccine-associated sarcomas. The widespread absence of COX-2 expression in most feline neoplasms might suggest that COX-2 inhibitors would have a low potential as anticancer agents.  相似文献   
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CASE DESCRIPTION: A 2.5-year-old spayed female Persian cat was evaluated for acute inability to close its mouth. CLINICAL FINDINGS: A wry-mouth malocclusion was evident, and the right side of the mandible was longer than the left side. The right mandibular tooth row appeared to be lowered. The lower jaw was persistently maintained in an open position. The presumptive diagnosis was open-mouth jaw locking. Diagnostic imaging with computed tomography and 3-dimensional reconstruction was performed for definitive diagnosis and to achieve a better understanding of the lesions. Imaging revealed locking of the right ramus of the mandible, which was displaced ventrolaterally, causing the coronoid process to impinge on the right zygomatic arch. TREATMENT AND OUTCOME: A bilateral partial ostectomy of the rostroventral margins of the zygomatic arches with an autogenous fat graft implantation was performed. The cat recovered without complications and by the following morning was bright, alert, and responsive and eating canned cat food comfortably. One year after surgery, the owner reported that the cat had continued to function well, was eating normally, and had not had any observed locking episodes since surgery. CLINICAL RELEVANCE: Unlike radiographic imaging, computed tomography may be used to create 3-dimensional reconstructions of structures in cases of suspected open-mouth jaw locking; improve evaluation of the lesions; and improve decision-making and client education for diagnosis, treatment options, and prognosis.  相似文献   
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An approximately 12-year-old female Vietnamese Pot-Bellied Pig was presented to the Mississippi State College of Veterinary Medicine Food Animal Service for anorexia of 2 days duration. On physical examination, the patient appeared depressed and lethargic with significantly pale mucus membranes, open mouth breathing, and nostril flaring. On abdominal palpation, the abdomen was tense and uncomfortable. A complete blood count (CBC) and chemistry profile were performed. The CBC revealed significant anemia and mild leukocytosis characterized by mild neutrophilia with a left shift. Mast cells were rarely observed. Hematocrit = 8.1% (RI 22-50), RBC = 1.25 × 106/μL (RI 3.6-7.8), WBC = 19.85 × 103/μL (RI 5.2-17.9), Neutrophils = 15.08 × 103/μL (RI 0-11.4), and Bands = 0.993 × 103/μL (RI 0-0.019). The chemistry profile was unremarkable with a mildly elevated BUN and slightly decreased total protein and albumin (BUN = 39 mg/dL [RI 4.2-15.1], total protein = 6.2 g/dL [RI 6.6-8.9], and albumin = 2.5 g/dL [RI 3.6-5.0]). An abdominal ultrasound revealed numerous hypoechoic nodules diffusely scattered throughout the hepatic parenchyma. An FNA of one of the hepatic nodules was performed. A mild suppurative component and numerous variably granulated mast cells were observed. A presumptive cytologic diagnosis of mast cell tumor was made. Histopathology was performed, confirming the cytologic interpretation.  相似文献   
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Ultrasonic interferometric measurements, developed for polycrystalline samples in a multi-anvil apparatus, were extended to single-crystal samples of San Carlos olivine and forsterite. The elastic moduli, C22 and C55 of San Carlos olivine and C55 of pure forsterite, were measured to about 13 gigapascals. These data on C22 for San Carlos olivine and C55 for forsterite are consistent with earlier measurements and extrapolations. The C55 for San Carlos olivine increases linearly as a function of increasing pressure, unlike the earlier nonlinear behavior observed at high pressure with impulsive stimulated scattering techniques.  相似文献   
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Temperatures in Jupiter's atmosphere derived from Galileo Probe deceleration data increase from 109 kelvin at the 175-millibar level to 900 ± 40 kelvin at 1 nanobar, consistent with Voyager remote sensing data. Wavelike oscillations are present at all levels. Vertical wavelengths are 10 to 25 kilometers in the deep isothermal layer, which extends from 12 to 0.003 millibars. Above the 0.003-millibar level, only 90- to 270- kilometer vertical wavelengths survive, suggesting dissipation of wave energy as the probable source of upper atmosphere heating.  相似文献   
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