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171.
Milks from commercial dairy herds in Southeastern Pennsylvania were analyzed for total protein, casein, whey protein, beta-lactoglobulin, nonprotein nitrogen, and lactose contents. Data for fat contents and milk yields were from Dairy Herd Improvement Association records for the same lactation. Milk samples were from a single milking of healthy cows (151) in midlactation. Since the remainder of the milk was returned to the bulk milk of the farm, the data represent market milk composition. The data were grouped and analyzed by breed and beta-lactoglobulin phenotype; there were 18 to 33 cows per breed. In true protein percentage, the breeds ranked: Jersey 4.07 plus or minus .49, Brown Swiss 3.84 plus or minus .47, Guernsey 3.56 plus or minus .53, Ayrshire 3.30 plus or minus .52, Milking Shorthorn 3.17 plus or minus .47, Holstein 3.07 plus or minus .43. Breeds differed in all other components and in milk yield. Brown Swiss ranked highest in yield of protein. Only whey protein and beta-lactoglobulin contents were influenced by the beta-lactoglobulin genotype with beta-lactoglobulin A greater than AB greater than B in whey protein content. 相似文献
172.
The paper concerns the production of highly oriented polyethylene by means of pressing the softened but essentially still solid material through a reducing capillary between 90 and 120° C. The objectives were to explore this route towards the achievement of high tensile modulus and to assess its practicability, both of which are presented in the paper. In addition, however, information was obtained relevant to deformation processes and to the relation between tensile properties and microstructure in general. Thus the induced deformation in the solid state and its dependence on processing variables was found to be interpretable in terms of Eyrings theory of viscosity with simple shear as an important element. Both changes in the fold length and fold content could be followed most informatively by low frequency Raman spectroscopy and it was observed, in the course of the present solid-state deformation, that the chains partly refolded to a fold length appropriate to the processing temperature, and partly unfolded. The former is in accord with earlier analogous observations on cold-drawing [13], the latter, as assessed through the reduction of fold content, correlated in an apparently uniquely defined way with the measured tensile modulus where the lowering of the fold content corresponds to an increase in modulus. Thus, this Raman spectroscopically determined fold content represents a promising new parameter in the correlation of structure with properties, it is applied further in the present paper for assessing modulus variation across the width of the extrudate. Other observations on the extrudate include a quantitative analogy with wood, the fibrous structure element being the common denominator. 相似文献
173.
Ocular abnormalities and psychomotor difficulties were prominent in two unrelated children; in addition, the older child had respiratory irregularity during sleep. The pathologic findings included lesions of the optic nerve in the case with available material and established the diagnosis of Leigh's subacute necrotizing encephalopathy. This disorder is thought to result from inhibition of a thiamine-dependent enzymatic process and may be modified by greatly increased thiamine intake. Suspicion of the diagnosis in a child with ophthalmoplegia or other ocular abnormalities may lead to earlier recognition and more successful treatment of the disease. 相似文献
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176.
Medical definitions of occupational and professionally conditioned pathology are given in the article together with relevant examples. With the view to account appropriately occupational pathology in accordance with its severity classification based on the degree of working capacity loss is presented. Notions of acute occupational disease (intoxication) and professional accident are determined. International list of occupational diseases is considered. Suggestions intended at promotion of safe working conditions are made on perfection of the Ukrainian list. 相似文献
177.
The new American Association on Mental Retardation (AAMR) definition of mental retardation (Luckasson et al., 1992) represents a radical departure from previous definitions. In the present paper we examined the extent to which the new definition provides decision rules to guide clinicians and researchers in classification efforts. We concluded that the IQ criterion of 75 will increase the proportion of the general population eligible near the cut-off score. Moreover, the 10 adaptive skill areas adopted fail to consider developmental factors and cannot be assessed reliably with current scales. Proposed differentiation by levels of needed supports is also challenged as being imprecise and not amenable to reliable measurement. Implications of this new definition for diagnostic practices and research endeavors were explored. 相似文献
178.
FS Machado EC Telles L Fouto EP da Silva N Lan?a I de Oliveira 《Canadian Metallurgical Quarterly》1996,15(6):465-71, 459
The objective of this study is to contribute to the positioning of the intravenous digital subtraction angiography (IVDSA) in the detection of morphologic abnormalities of renal arteries (RAs), susceptible to originate renovascular hypertension (RVH). The authors focus on the prevalence of RVH in the broad spectrum of systemic arterial hypertension. The definition of RVH is given and its diagnostic criteria are revisited. The angiography methods used in the evaluation of RAs morphologic abnormalities are described. 相似文献
179.
EP Pélissier 《Canadian Metallurgical Quarterly》1998,17(6):613-621
Pentavalent rhenium-188 dimercaptosuccinic acid [188Re(V)DMSA] is a beta-emitting analogue of 99mTc(V)DMSA, a tracer that is taken up in a variety of tumours and bone metastases. The aim of this study was to develop the kit-based synthesis of the agent on a therapeutic scale, to assess its stability in vivo, and to obtain preliminary biodistribution and dosimetry estimates, prior to evaluation of its potential as a targeted radiotherapy agent. The organ distribution of 188Re in mice was determined 2 h after injection of 3 MBq 188Re(V)DMSA prepared from eluate from a 188W/188Re generator. Three patients with cancer of the prostate and three with cancer of the bronchus, all with bone metastases confirmed with a standard 99mTc-hydroxymethylene diphosphonate (99mTc-HDP) scan, were given 370 MBq 188Re(V)DMSA and imaged at 3 h and 24 h using the 155-keV gamma-photon (15%). Blood and urine samples were collected to determine clearance and to analyse the speciation of 188Re. Organ residence times were estimated from the scans, and used to estimate radiation doses using MIRDOSE 3. In mice, 188Re(V)DMSA was selective for bone and kidney. In patients, it showed selectivity for bone metastases (particularly those from prostate carcinoma) and kidney, but uptake in normal bone was not significantly greater than in surrounding soft tissues. Of the normal tissues the kidneys received the highest radiation dose (0.5-1.3 mGy/MBq). The images were strongly reminiscent of 99mTc(V)DMSA scans in similar patients. High-performance liquid chromatography analysis of blood and urine showed no evidence of 188Re in any chemical form other than 188Re(V)DMSA up to 24 h. In conclusion, 188Re(V)DMSA and its 186Re analogue warrant further clinical assessment as generator/kit-derived agents for treatment of painful bone metastases. These agents should also be assessed in medullary thyroid carcinoma and other soft tissue tumours which have been shown to accumulate 99mTc(V)DMSA. 相似文献
180.