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31.
The growth of carcass tissues and developmental changes in tissue distribution were studied in three pig types which were selected to have morphologies that could be described as attenuated, blocky and flabby. These were achieved by incorporating, respectively, Landrace, Pietrain and Meishan genes to give commercial 'types' (designated L, P and M,) exhibiting some of the phenotypic qualities of these breeds. Twenty-five female pigs of each type with an average start weight of 27.2 kg were fed ad libitum and slaughtered over a (nominal) live weight range of 35-115 kg. Relations were quantified using the logarithmic transformation of data in the allometric model. Significant type differences in relative growth rates (the b coefficient or slope in the logarithmic plot) were not common, occurring in 14% of the relationships examined, whereas 61% of differences in the constant term (a or intercept in the logarithmic plot) were significant. Increase in carcass weight with age was not different between the types but in relation to slaughter live weight (dressing percentage) P had the highest value, M the lowest. Carcass dimensions showed that, relative to body length, P had the widest ham and shoulder over the whole size range whereas M had a deep (ventral-dorsal) shoulder and wide belly, attributes of shape that would be regarded as undesirable by the meat trade. Relative to carcass weight, L was only slightly longer (3 mm) in the body than M at the heavy end of the weight range but markedly longer (29 mm) than P. These differences in carcass conformation were also evident in the shape of pelvic limb muscles which, at a given length, were lightest and narrowest in M and, in some cases, heavier and wider in P than in L. Pelvic limb volume relative to limb length was greatest in P and least in M. Carcass composition (at a given prepared side weight) of P was characterized by low fat and high lean weights, and a high lean to bone ratio. Subcutaneous fat b was lowest in P, indicating that P was early maturing, but M carcasses had the most subcutaneous and intermuscular fat, also indicative of early maturing. There was, thus, no simple relation between maturity characteristics and carcass composition. M carcasses also had the greatest weight of skin. P had a light hindloin and heavy pelvic limb, M a heavy shoulder, hindloin and flank but a light pelvic limb; L had a light shoulder but a heavy foreloin. The distribution of individual tissues mirrored these differences in joint weights to a varying extent; in most cases the match (relatively heavy/light) was with a single tissue. These data, thus, indicated some pig type differences in tissue distribution and of particular significance was the relatively light lean mass in the pelvic limb of M. The results showed important differences in carcass quality between commercially available pig types differing in conformation.  相似文献   
32.
We present a new peak-detection algorithm based on the method of 'minimum average risk' proposed by Kolmogorov and developed for signal processing in various fields. In this method, translations of features within a signal scan are quantified by minimizing the integrated pointwise product of each scan relative to the first derivative of the immediately previous scan. We have adapted this method for use in a new algorithm to monitor dynamic changes of sarcomere length in single myofibrillar sarcomeres of striated muscles, but the algorithm can also be used more generally for peak localization. We find that this method results in sub-nanometer precision and higher signal-to-noise ratio than current methods. At an equal noise level, the RMS deviation of the minimum average risk algorithm was 1.3 times lower than that of the center of mass method with modeled data and 3-4 times lower with actual data.  相似文献   
33.
34.
We introduce two parameters, large-scale and small-scale rms roughness, to take into account the interface properties of thin films and multilayers in the calculation of their specular reflectance and transmittance. A theoretical motivation for the introduction of these two parameters instead of a standard single rms roughness is provided. Experimental power spectral density functions of several samples are used to illustrate ways in which the parameters introduced can be evaluated.  相似文献   
35.
The relationships between coefficients of electromechanical coupling (CEMC) of various types of piezoceramic resonator (PR) vibrations are considered. Being constant for a given piezoceramic state, the range of variation of piezoceramics dielectric permittivity from a mechanically "free" condition at relatively low frequencies up to an "overall clamped" condition at high frequencies is determined by a consecutive "clamping", caused by a complex of CEMCs of various particular vibrational modes peculiar to the resonator. As the difference between "free" and "overall clamped" permittivities is always determined by the maximal piezomaterial /spl kappa//sub i3/ coupling coefficient, the difference does not depend on the path that was gone through the low-high frequency range, which includes all the vibrational modes possible for a particular PR. The influence of the piezoelectric and elastic anisotropy of lead-zirconate-titanate (PZT) piezoceramic materials on relative CEMC variations was experimentally investigated.  相似文献   
36.
A Series of comparisons were conducted to test the capabilities of a range of metrological techniques and analytical laboratories engaged in the assay of thorium in the workplace. The results of these exercises are presented together with the decision criteria used to determine whether results are significantly different from the true value. The discussion highlights those aspects which warrant closer and further attention.  相似文献   
37.
Selenium level was determined in sera of 27 patients including 15 patients with chronic gastrointestinal diseases and 12 patients with intestinal malabsorption after some kinds of stomach or small intestine resection. Deficiency of this trace element was found in 5 patients and suboptimal concentration in 4 patients in the first group and in 3 and 5 patients of second group respectively. Supplementation of patients with 45 mg of selenium organic form based on autolysis extract of selenious baker's yeast resulted in increase of selenium level in 23 (85%) patients including all of them with selenium deficiency or suboptimal level. It was concluded about high bioavailability of selenium in supplement studied. Perturbed intestinal absorption after surgical resection of stomach or small intestine may be considered as an indication for prophylactic taking of organic selenium form preparation.  相似文献   
38.
Analysis of modern resources of normal human microflora correction has shown an importance of microbiological aspect in principles of a balanced feeding for realization of the optimum mechanism of normal human microflora maintenance.  相似文献   
39.
The carried out research of vitamin C status of 250 young people 17-20 years old constantly living in region of the periodic radioactive control of the Gomel region of Republic Byelorussia have shown, that in the spring the vitamin C deficiency is observed at more than 55% examined, and autumn this parameter is reduced approximately on 20%. The vitamin C provision of the women is slightly higher, than one of men. The vitaminization of the population within 1 month by polyvitaminic complexes results in twofold reduction of number examined with vitamin deficiency.  相似文献   
40.
The coevolution of genomics and proteomics has led to advancements in the field of diagnosis and molecular mechanisms of disease. Proteomics is now stepping into the field of obstetrics, where early diagnosis of pregnancy complication such as preeclampsia (PE) is imperative. PE is a multifactorial disease characterized by hypertension with proteinuria, which is a leading cause of maternal and neonatal morbidity and mortality occurring in 5-7% of pregnancies worldwide. This review discusses the probable molecular mechanisms that lead to PE and summarizes the proteomics research carried out in understanding the pathogenicity of PE, and for identifying the candidate biomarker for diagnosis of the disease.  相似文献   
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