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991.
Ultrasonography of the liver was performed in 200 Holstein-Friesian dairy cattle using a 3.5 MHz transducer with a linear array electronic scanner. Liver samples were taken, processed and examined microscopically and the fat occupying rate was calculated. The hepatic ultrasonograms were evaluated according to the presence of bright pattern, dark pattern, deep attenuation, vascular blurring and blurring of edges. Of the 200 animals, 96 had a normal liver, 63 had hydropic degeneration of the liver, 37 had fatty infiltration of the liver, 3 had liver dystrophy and I had hepatic amyloidosis, diagnosed through histopathological examination. Amyloidosis was characterized by bright pattern and blurring of edges. Liver dystrophy had higher percentages of bright pattern and blurring of edges than normal liver. Hydropic degeneration had higher percentages of dark pattern and blurring of edges than normal liver. Fatty infiltration had higher percentages of bright pattern, deep attenuation, vascular blurring and blurring of edges than normal liver. The present results suggest that different ultrasonographic patterns can be observed in various diffuse hepatocellular disorders in dairy cattle  相似文献   
992.
Rapid, efficient, and reproducible procedures for isolating DNA before PCR gene amplification are essential for the diagnosis of piroplasms. In this study, we evaluated the ease and reliability of detecting Theileria equi by PCR using pre-extracted DNA samples (by QIAamp DNA Mini Kit and phenol-chloroform methods) compared with blood spotted on FTA cards as PCR templates. Although minimal variations in limit of detection were observed among the methods compared, overall, the use of pre-extracted DNA samples and blood spotted on FTA cards had comparable detection limits. These results indicate that T. equi infection can be efficiently detected directly from FTA cards by PCR without the need for pre-extraction of DNA from blood samples.  相似文献   
993.
1. Four experiments were conducted on broiler chickens between one and three weeks of age to determine their response to dietary protein concentrations.

2. Diets prepared by serial dilution of a concentrated protein mixture, well‐balanced with respect to all essential amino acids, were fed in three experiments, while in a fourth experiment, a lysine‐deficient protein mixture was used.

3. Response curves relating body‐weight gain to increasing concentrations of protein and of lysine intake are presented.

4. A table is presented from which optimum protein intakes can be calculated according to changes in input and output costs and changes in growth potential of the chickens.  相似文献   

994.
Thyroid scintigraphy using sodium 99mTechnetium pertechnetate (99TcO4-) was performed in normal and radiothyroidectomized cockatiels ( Nymphicus hollandicus ). 131I scintigraphy was performed in the course of ablating the thyroid glands. The thyroid glands in normal birds were clearly visualized, but were not individually resolvable. Thyroid glands were not visualized in thyroid-ablated birds. With 99mTcO4 scans, thyroid (or other region of interest)/body count density ratios were used for comparisons of normal and thyroid-ablated birds. Normal 99mTcO4- thyroid/body ratios (mean +/− SD) for the dorsal and lateral views were 1.83 +/− 0.31 and 1.70 +/− 0.34 respectively. Pertechnetate thyroid/body count density ratios decreased (to 0.93 -/−0.14 and 0.88 +/− 0.12 for dorsal and lateral views respectively) after thyroid ablation, while crop/body ratios increased. 99mTcO4- thyroid scintigraphy, therefore, was capable of detecting hypofunctional thyroid abnormalities in 131I radiothyroidectomized cockatiels.  相似文献   
995.
996.
In order to optimise production of the edible flower buds produced by myoga (Zingiber mioga Roscoe) a greater understanding of the growth and development of the plant and factors influencing flower initiation and development are required. The vegetative growth phase in myoga was characterised by a distinct period of pseudostem development from the planted rhizome piece followed by an extended period of rhizome growth from both the base of pseudostems and the planted rhizome piece. The transition from pseudostem formation to the initiation of rhizome growth occurred at the same time as the dry weight of the planted rhizome piece ceased to decline. Flower bud initiation and development occurred over an extended period, beginning soon after the commencement of new rhizome growth and ending prior to foliage senescence. Flower buds were observed at the terminal meristem of first, second, third and fourth order rhizomes. Increasing temperatures stimulated both increased vegetative growth and flower bud initiation and development. Low flower bud yields recorded under conditions of low temperature were the result of reduced rate of floral initiation and not abortion of flower buds. Increased shading of plants grown under glasshouse conditions resulted in reduced flower bud yield and similarly the response resulted from decreased initiation rather than abortion.  相似文献   
997.
The success of many intercropping systems in North America is attributable to the generation of a short term return from an agricultural crop during the early, unprofitable years of a longer term crop that is fruit, nuts or wood. This highly-efficient use of land and related profitability are important not only in the development of intercropping systems per se, but also in other applications which have tremendous potential independent of profitability. For example, intercropping can be effectively used during the establishment phases of hardwood plantations where it is essential to have a high level of weed control, the costs of which are often recovered with the agricultural production. Intercropping can also be used to grow trees rapidly and with a form that can be easily integrated into recreational or park situations, or urban fringe areas. In an urban context, intercropping can be used to grow trees in agricultural areas that are likely to be developed where traditional forestry options are not appropriate and the value of younger, thrifty trees may enhance property values far in excess of the cash value of the wood.  相似文献   
998.
Mildly extracted peanut allergen Ara h 1 was previously reported to occur as an oligomeric complex. In this paper we describe how the protein in this oligomeric complex interacts noncovalently with phenolic compounds of the proanthocyanidin type. These interactions are being disrupted during anion exchange chromatography, resulting in the dissociation of the oligomeric Ara h 1 complex into protein trimers. By use of the known three-dimensional structure of beta-conglycinin, a soy protein homologous to Ara h 1, proline-rich regions were observed in silico on both faces of its trimeric structure, which are conserved in Ara h 1. These proline-rich regions could explain the binding of proanthocyanidins to Ara h 1 and the formation of multiple Ara h 1 trimer complexes. This was supported by the observation that the addition of peanut proanthocyanidins to trimeric Ara h 1 and to beta-conglycinin resulted in the formation of soluble oligomeric protein complexes. The structurally related legumin proteins do not contain such proline-rich regions on both sides of the protein, and proanthocyanidins were shown to have a lower affinity for legumin proteins from peanuts and soybeans (peanut allergen Ara h 3 and soy glycinin, respectively). Ara h 1 present as the oligomeric complex is assumed to be the representative form of the allergen in which it is consumed by humans.  相似文献   
999.
Sorption of Cd at low concentrations onto river Rhine suspended matter was examined in terms of sorption rate, reversibility and factors such as competition and complexation with major inorganic sea-water ions. More than 90% of the final amount of Cd is sorbed within the first few hours. Desorption experiments show that the process is virtually reversible. In experiments with diluted sea water the sorption of Cd strongly decreases even at low salinity. Sorption isotherms show that the sorption of Cd in NaNO3 solutions is regulated by the free Cd2+ activity. In a Ca(NO3)2 environment the Cd sorption decreases with increasing Ca2+ concentrations, which implies competition between Ca2+ and Cd2+ for the different sorption sites. In different electrolyte solutions of similar ionic strength the sorption of Cd decreases in the solution order NaNO3 > NaCl > NaCl+MgCl2+CaCl2 > diluted sea water. Although inorganic speciation calculations show that even at low salinities dissolved Cd is dominated by Cd-chloro complexes, chloride accounts for only about one third of the increased mobility of Cd. As a result of addition of Ca2+ and Mg2+ the sorption capacity of suspended matter for Cd is further reduced by a factor three.  相似文献   
1000.
A monoclonal antibody to an Albanian isolate of plum pox potyvirus (PPV) was obtained (MAbAL), that specifically recognized strain M of this virus. The specificity of MAbAL, assessed by comparative ELISA on 130 PPV isolates of different geographical origin, 22 of which were also tested by comparative IC-PCR, gave consistent and highly reproducible results. MAbAL seems to be elicited by a stable surface determinant that makes it particularly suitable for successful use under a wide range of conditions. MAbAL is an useful addition to the panel of PPV-specific MAbs available to date.  相似文献   
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