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981.
A randomized complete block design experiment with 30 yearling crossbred steers (average BW = 436.3 ± 39.8 kg) fed a steam-flaked corn-based diet was used to evaluate the effects dietary vitamin A (Rovimix A 1000; DSM Nutritional Products Ltd., Sisseln, SUI) supplementation on myogenic gene expression and skeletal muscle fiber characteristics during the finishing phase. Steers were blocked by BW (n = 5 blocks; 6 steers/block), randomly assigned to pens (n = 2 steers/pen), and one of the following treatments: no added vitamin A (0 IU; 0.0 IU/kg of dietary dry matter intake of additional vitamin A), vitamin A supplemented at the estimated requirement (2,200 IU; 2,200 IU/kg of dietary dry matter (DM) of additional vitamin A), and vitamin A supplemented at 5× the estimated requirement (11,000 IU; 11,000 IU/kg of dietary DM of additional vitamin A). After all treatments underwent a 91-d vitamin A depletion period, additional vitamin A was top-dressed at feeding via a ground corn carrier. Blood, longissimus muscle, and liver biopsy samples were obtained on days 0, 28, 56, 84, and 112. Biopsy samples were used for immunohistochemical and mRNA analysis. Sera and liver samples were used to monitor circulating vitamin A and true vitamin A status of the cattle. Expression for myosin heavy chain (MHC)-I diminished and rebounded (P = 0.04) over time. The intermediate fiber type, MHC-IIA, had a similar pattern of expression (P = 0.01) to that of MHC-I. On day 84, C/EBPβ expression was also the greatest (P = 0.03). The pattern of PPARγ (P < 0.01) and PPARδ (P < 0.01) expression seemed to mimic that of MHC-I expression, increasing from days 84 to 112. Distribution of MHC-IIA demonstrated a change over time (P = 0.02). Muscle fiber cross-sectional area increased by day (P < 0.01) for each MHC with the notable increase between days 0 and 56. Total nuclei density decreased (P = 0.02) over time. Cells positive for only Myf5 increased (P < 0.01) in density early in the feeding period, then declined, indicating that satellite cells were fusing into fibers. The dual-positive (PAX7+Myf5) nuclei also peaked (P < 0.01) around day 56 then declined. These data indicated that gene expression associated with oxidative proteins may be independent of vitamin A status in yearling cattle.  相似文献   
982.
983.
Jackfruit latex gum was applied to pigment printing of cotton fabrics as a binder and their printing properties were compared with those of conventional pigment printing. The printing performances were influenced by the content of Jackfruit latex gum in the binder and the curing conditions. Based on a series of experiments, the pigment printing paste recipe and the process were optimized, considering color fastness, color strength, and fabric handle properties compared with those of the synthetic binder. The use of combined binder containing Jackfruit latex gum for pigment printing showed reasonable printing performances and offers an option for replacing synthetic binders, which cause adverse effect on human health and environments.  相似文献   
984.
Jeryl C.  Jones  DVM  PHD  Judith A.  Hudson  DVM  PhD  Donald C.  Sorjonen  DVM  MS  Charles E.  Hoffman  CVT  BS  LATG  Kyle G.  Braund  BVS  MVS  PhD  James C.  Wright  DVM  MS  PhD  Phillip D.  Garrett  DVM  MS  Jan E.  Bartels  DVM  MS 《Veterinary radiology & ultrasound》1996,37(2):133-140
Intraoperative Doppler ultrasonography was used to measure the effects of four experimental nerve root compression treatments (central compression, central-plus-lateral compression, lateral compression, and compression release) on arterial blood flow velocities in the seventh lumbar spinal ganglion of three dogs. Graphed blood flow velocity changes (change = treatment value − pretreatment value) were below baseline during the first three compression treatments and above baseline following compression release. Mean blood flow velocity changes for both central-plus-lateral compression and lateral compression differed (p ≤ 0.05) from changes for central compression. Changes for central-plus-lateral compression did not differ (p > 0.05) from changes for lateral compression. Changes among the first three compression treatments differed (p ≤ 0.05) from changes for compression release. No histologic abnormalities were identified in compressed nerve tissues, compared to contralateral controls. These findings indicate that stenosis within the L7-S1 intervertebral foramen may cause ischemia of the L7 spinal ganglion in dogs.  相似文献   
985.
Blood acid-base and electrolyte status was studied in four sedentary Miniature Horses treated with 200, 300, 400 and 500 mg of sodium bicarbonate (NaHCO3) per kg of body weight (BW). Arterial blood was collected before treatment with NaHC03 and each hour for 5 h after treatment. All treatments resulted in an increase in blood pH, bicarbonate (HCO3) concentration and base excess (BE) by 1 h post-dosage, which continued through the 5th hour (P < .05). Treatment with 200 mg NaHC03/kg BW resulted in less elevated blood HCO3 concentrations (P < .03) and BE values (P < .01) when compared to the other treatments. Following dosing with NaHCO3, plasma Na+ concentrations increased among all treatments but declined to initial values by 3 h post-treatment. The 200 mg NaHCO3/kg BW dosage resulted in the smallest increases in plasma Na+ concentrations (P < .03). Both plasma K+ and Ca++ concentrations were lower (P < .05) among all treatment groups 1 h post-dosage but returned to initial values by 5 h and 3 h posttreatment, respectively, with no differences (P >.05) among treatments. All NaHCO3 dosages increased blood buffering capacity as indicated by increased blood pH, HCO3 concentration and BE. Maximum blood pH, HCO3 concentration and BE was reached using a dosage of 300 mg NaHCO3/kg BW. Also, all treatments altered the plasma electrolyte concentrations.  相似文献   
986.
Renal allograft transplantation was performed as treatment for terminal renal failure in six veterinary patients. Three patients failed to survive the postsurgical period, one patient died due to acute allograft rejection, one patient died subsequent to complications of previous parenteral hyperalimentation and infection, and one patient was euthanatized due to the inability of the clients to maintain the effort necessary to manage a transplant recipient. Further clinical studies are necessary to determine if renal transplantation with cyclosporine (cyclosporin A)/prednisolone immunosuppression has the potential to provide practical treatment of terminal renal disease in clinical veterinary medicine. Pharmacologic and immunologic monitoring of transplant recipients with individualized immunosuppression is imperative. Careful surveillance is necessary to identify and eliminate nosocomial sources of infection. Candidates for transplantation cannot be critically ill or malnourished prior to surgery, and pet owners must be prepared for the financial and time commitments associated with caring for a renal allograft recipient.  相似文献   
987.
Twenty g sample, to which sulfamerazine has been added as internal standard, is extracted with 0.3N HCl + 1.5% diethylamine in 25% methanol. The sample extract is chilled (to aid clarification), centrifuged, and filtered. The sulfonamides are separated from each other and from co-extracted materials on a C-18 reverse-phase column and detected at 450 nm following post-column derivatization with dimethylaminobenzaldehyde. Two isocratic mobile phases have been tested: (1) acetonitrile-2% acetic acid (17 + 83), with an analysis time of 13 min; and (2) acetonitrile-methanol-2% acetic acid (4 + 16 + 80), with an analysis time of 20 min but an improved analysis for some samples. As many as 40 samples have been analyzed at one time unattended with the aid of an autosampler. A total of about 1500 field samples have been assayed using the method. Method sensitivity is 0.1 ppm for either analyte in a hog finishing fed. Linearity for each of the analytes is satisfactory over a range of 0.4-25 ppm in spiked feeds. Coefficients of variation range from 13% at 0.5 ppm to 2% at 13 ppm as tested over a period of time in naturally contaminated samples. The absolute recovery of sulfamerazine varies with sample matrix, but, in the presence of sulfamerazine as internal standard, recovery has been 96.7-99.7% over the range of 0.1-10 ppm. Sulfamerazine and sulfamoxole were tested for their suitability as internal standards. Sulfamerazine is a good internal standard for sulfamethazine; neither is ideal for sulfathiazole.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
988.
The efficacy of 3% chloroxylenol (PCMX) or 4% chlorhexidine gluconate (CG) for preoperative skin preparation was assessed in 100 dogs undergoing clean or clean-contaminated surgical procedures. Replication Organism Detection and Counting (RODAC) plates were used to quantify skin bacteria colony forming units (CFU) at the operative site before and after skin preparation and immediately postoperatively. Reduction of CFU after skin preparation and immediately postoperatively was significant for each agent. However, CFU levels were significantly lower in the CG group than in the PCMX group after surgical preparation, regardless of initial CFU numbers. No significant difference in CFU counts was observed between antiseptic groups postoperatively. Within-group comparisons showed PCMX to be significantly less efficacious when the prescrub CFU number was greater than 1,000. Bacterial reduction was similar in the CG group regardless of prescrub CFU levels. The number of negative cultures after skin preparation was significantly greater with CG than with PCMX. Chlorhexidine gluconate also had fewer cultures with heavy bacterial growth (>5 CFUs) after surgical preparation. There was no significant difference between antiseptics in the number of negative cultures or cultures with more than 5 CFUs immediately after surgery. The number of skin reactions and postoperative wound infections that occurred with each technique were similar. Three percent PCMX, as used in this study, was less effective than 4% CG in its immediate antimicrobial activity, however, this difference was not associated with an increased wound infection rate.  相似文献   
989.
Following head trauma, the left globe of a Red Tail Hawk showed demonstrable indentation on palpation. Recurrent anterior chamber collapse and reformation dependent on head position was the most significant clinical finding. A fracture of the scleral ossicles in the caudal portion of the scleral ring was identified in the rostrocaudal radiograph of the skull. Conservative management of the fracture resulted in phthisis bulbi. Fractured scleral ossicles have been shown radiographically in the enucleated globe but have not been previously demonstrated in the eye of the living bird.  相似文献   
990.
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