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1.
This paper examines the views of members of the veterinary profession towards the change in orientation of professional practice that is occurring. It contrasts the values of veterinarians with those of doctors, dentists, lawyers and accountants. Particular attention is given to the areas of business efficiency, competition and advertising. Data was derived from self-completion questionnaires containing 40 Likert scales which were mailed to 300 members of each of the five professions. 相似文献
2.
Alkaline phosphatase (APase) activity in tissue samples, with adherent bacteria, was measured from two sites in the rumen and from two sites in the abomasum of 57 yearling Angus and Hereford bulls and heifers fed a high or a low energy diet. In the rumen, APase activity was higher at the caudoventral blind sac than at the dorsal sac in animals of both breeds fed the high energy diet and in Angus bulls fed the low energy diet, but the reverse was observed in Hereford bulls fed the low-energy diet (P less than .01). In the abomasum, APase levels were higher for bulls than heifers (P less than .01) and higher at the fundic than at the pyloric region (P less than .01). Morphological studies also showed that rumen samples from animals fed a high energy diet exhibited a more widely distributed APase activity and an increase in the digestive recycling of epithelial cells that produced some "pitting" of the tissue. The higher APase activity of the epithelial tissue of animals fed the high energy diet may be explained by the greater rate of cell death and renewal indicated by the higher mitotic index reported by other researchers who have studied the cell cycle of the rumen epithelium in ruminants fed high and low energy diets. 相似文献
3.
Tongjun Ren Shunsuke Koshio Orhan Uyan Connie Fay Komilus Saichiro Yokoyama Manabu Ishikawa Md Kadel Abdul 《Journal of the World Aquaculture Society》2008,39(6):797-803
A trial was conducted to determine the effect of ascorbyl‐2‐monophosphate Na/Ca (AMP‐Na/Ca) on blood chemistry and nonspecific immune response of red sea bream juveniles. Test diets with three levels of AsA (free, 107, and 325 mg/kg diet) were fed to juvenile red sea bream (36.0 ± 1.3 g) two times a day for 3 wk. There were no significant differences in hematocrit, glucose, and blood urea nitrogen. Total cholesterol and triglyceride in plasma of fish fed AsA‐free diet was significantly (P < 0.05) higher than that of fish fed two other diets. There were no significant differences in serum albumin, total bilirubin, and total serum protein. Glutamyl oxaloacetic transaminase in serum of fish fed diets containing 107 and 325 mg of AsA were significantly (P < 0.05) lower than that of fish fed AsA‐free diet. Serum lysozyme activity (LA) of fish fed diets containing 107 and 325 mg of AsA were significantly (P < 0.05) higher than that of fish fed AsA‐free diet. There was no significant difference in mucus LA. The results mentioned above demonstrated that AMP‐Na/Ca is a bioavailable AsA source for red sea bream juveniles. Supplement of more than 107 mg AsA/kg in diets improved blood chemistry and nonspecific immune function of red sea bream juveniles. 相似文献
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5.
Summary The seasonal cambial activity of balsam fir producing normal and compression wood was observed. Samples were taken throughout one growing season. Activity was initiated in normal wood with the precocious development of one sieve cell per file 2 weeks before activity was initiated in compression wood with the formation of one new sieve cell per file. Deactivation dates in normal and compression wood were the same.Dating of the phloem adjacent to normal wood can be carried out using crushed sieve cells or an annually formed band of tannin filled parenchyma whereas adjacent to compression wood, only crushed sieve cells can be used.The maximum cambial zone widths in normal and compression wood were 15 and 16 cells, respectively. The final xylem to phloem ratio in normal wood was 14:1 while in compression wood it was 21:1.Time required for development of tracheids was examined throughout the growing season. Growth trends for the radial growth and differentiation phases were studied in both normal and compression wood. Tracheid development in normal wood took between 14 and 33 days while in compression wood it varied between 5 and 49 days.Research financed under McIntire-Stennis Research Project 5009 and COE Projects R625-173 and R625-195 相似文献
6.
P. Sittisart M. M. Hyland M. A. Hodgson C. Nguyen A. Fernyhough 《Wood Science and Technology》2014,48(4):841-853
The aim of this project was to fabricate electroless nickel-coated cellulose fibres. Ultimately, these nickel-coated cellulose fibres will be used to develop a cost-effective polymer composite for electromagnetic interference (EMI) shielding and/or electrostatic discharge (ESD) applications. An attempt has been made to impart electrical conductivity onto cellulose fibres via an electroless nickel plating process. The aim was to achieve a homogeneous, continuous layer of Ni on the cellulose fibres, and the plating conditions were optimized to achieve this. The relationship between the coating morphology and the performance of the coated fibre was also of interest. Testing was carried out using cellulose filter paper and then loose cellulose fibres. Scanning electron microscopic (SEM) images of nickel-coated filter paper showed that nickel particles are bonded to the cellulose fibres. The coating appeared more compacted and continuous as plating time increased, corresponding to lower surface resistivity. This observation suggested a correlation between morphology and electrical conductivity of the coating. For nickel-coated cellulose fibres, after optimization of plating conditions, a uniform deposition of nickel particles around the cellulose surfaces was confirmed by SEM images. EDS and XRD results confirmed similar coating could be produced on filter paper and cellulose fibres. SEM images of cross-sectioned nickel-coated cellulose fibres illustrated nickel particles had penetrated into the inner walls of the cellulose fibres. This impregnation of the fibres should act to increase the bonding between nickel coating and cellulose fibres. These nickel-impregnated cellulose fibres could now be incorporated into a polymer matrix to create an electrically conducting composite with the right processing parameters. 相似文献
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8.
This study vividly presents results from a seasonal particulate matter measurement campaign conducted at world’s largest ship-breaking yard i.e., Alang-Sosiya (Gujarat, India) at six locations and a reference station at Gopnath which is 30 km south of this ship-breaking yard. The collected suspended particulate matter (SPM) 24-h samples were critically analyzed for heavy metals (Pb, Cd, Co, Ni, Cr, Mn, Fe, Cu, Zn). The average concentration of SPM within the ship-breaking yard during the investigation was 287.5 ± 20.4 μg m?3 and at reference station it was 111.13 ± 5.81 μg m?3. These values are found to be in excess of the permitted national standards. The levels of heavy metals at Alang-Sosiya are very high as compared to US EPA and WHO guidelines. The mean concentrations of all metals are in the order: Fe >>Zn >Cu > Mn > Cd >Pb > Co >Ni >Cr. The results on enrichment factors (EF) suggest that most of the metals in the ship-breaking yard exhibit EF values of near or above 100 which must have been comprehensively affected by ship-breaking activities. Metal data was used to evaluate the role of spatial factors on their distribution characteristics. Thereafter, factor analysis was carried out to identify the main components liable for the variance of the data set. 相似文献
9.
Engelman JA Zejnullahu K Mitsudomi T Song Y Hyland C Park JO Lindeman N Gale CM Zhao X Christensen J Kosaka T Holmes AJ Rogers AM Cappuzzo F Mok T Lee C Johnson BE Cantley LC Jänne PA 《Science (New York, N.Y.)》2007,316(5827):1039-1043
The epidermal growth factor receptor (EGFR) kinase inhibitors gefitinib and erlotinib are effective treatments for lung cancers with EGFR activating mutations, but these tumors invariably develop drug resistance. Here, we describe a gefitinib-sensitive lung cancer cell line that developed resistance to gefitinib as a result of focal amplification of the MET proto-oncogene. inhibition of MET signaling in these cells restored their sensitivity to gefitinib. MET amplification was detected in 4 of 18 (22%) lung cancer specimens that had developed resistance to gefitinib or erlotinib. We find that amplification of MET causes gefitinib resistance by driving ERBB3 (HER3)-dependent activation of PI3K, a pathway thought to be specific to EGFR/ERBB family receptors. Thus, we propose that MET amplification may promote drug resistance in other ERBB-driven cancers as well. 相似文献
10.
Gauthier-Jaques A Bortlik K Hau J Fay LB 《Journal of agricultural and food chemistry》2001,49(3):1117-1122
An analytical method capable of identifying >30 chlorophyll-related compounds in plant extracts has been developed. The method employs liquid chromatography coupled to UV-vis, MS, and MS/MS detection. It can be applied without modification to analyze natural chlorophyll degradation products and other metalloporphyrines. It was successfully applied to identify chlorophyll derivatives found in rehydrated spinach powder and conventionally canned and Veri-Green-processed beans. In the Veri-Green-processed beans several degradation products were identified that are zinc-containing analogues to the chlorophyll derivatives found in vegetables after conventional canning. They have been characterized by liquid chromatography and mass spectrometry. 相似文献