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111.
Duck meat consumption is low but steady in the United States (US), while rapidly expanding in other countries. The duck industry is moving from a traditional whole carcass product towards deboned breast fillets and other portions, which has prompted strain selection for breast weight and yield. The effect of bird strain was therefore evaluated for fillet weight, yield, and breast meat quality characteristics. Eighty butterflied paired fillets were obtained from each of 4 Pekin duck strains after carcasses were sized by weight at the processing plant (n = 640). All fillets were weighed and then half of the fillets were evaluated for color. One fillet from each carcass-pair was either frozen or kept fresh for cooking, reweighing, and subsequent color analysis (Commission Internationale de I'Eclairage (CIE) lightness L*, redness a*, and yellowness b*). Both fillets in each carcass-pair were evaluated using Allo–Kramer (AK) and Warner–Bratzler (WB) shear. Strain affected (P < 0.05) raw and cooked fillet weight. Strain C, with the largest BW and selected for both breast yield and growth rate, had higher raw and cooked breast weight. Cooked yield was not affected by strain and averaged 64.4%. Neither AK nor WB shear values were affected by strain, and averaged 4.8 kg/g and 4.2 kg, respectively. Strain had a slight but significant effect on color, affecting lightness (L*) values of all categories, and redness (a*) values of raw and cooked meat. Freezing and thawing produced large and significant thaw losses ranging from 10.4 to 13.6%; differing losses depended on the strain of duck. Duck strain affected breast fillet weights and lightness to a slight extent, but not cook yield or shear values.  相似文献   
112.
试验选用体重约8kg的三元杂交(杜长大)猪60头,随机分成3组,每组2个重复,分别饲喂含不同剂量中华富铁康900的饲粮,研究中华富铁康900对仔猪生产性能、肤色的影响。结果表明,以中华富铁康900取代饲粮中部分硫酸亚铁,显著提高仔猪平均日增重(P<0.05),显著降低料重比(P<0.05),明显改善仔猪肤色。根据试验效果,仔猪饲粮中中华富铁康900的添加量为2×10-4~4×10-4。  相似文献   
113.
随着城市的发展,园林植物在景观上的作用越来越重要,文章主要分析园林植物外在的线条、外形、质地、色彩的特性,并归纳了一些处理植物配置与色彩、质地、距离、光影、地形等之间关系的艺术手法。  相似文献   
114.
二维结合彩色多普勒超声对诊断乳腺肿块的价值   总被引:1,自引:1,他引:0  
目的探讨二维及彩色多普勒超声(CDFI)对乳腺肿块鉴别诊断的价值。方法120例女性患者,术前应用二维超声观察乳腺肿块的大小、形态、位置、边界、包膜、内部回声;采用CDFI检测肿块周边及内部的血流形态、特点,并将彩色血流分为0~Ⅲ级。结果超声诊断乳腺肿块检出率为100%,良、恶性肿瘤超声诊断符合率分别为88.5%、85.7%。良性肿瘤多表现为边界光滑,侧缘回声减弱,CDFI血流分级以Ⅰ~Ⅱ级为主;恶性肿瘤多表现为形态不规则,边界不清,内部回声不均,CDFI血流分级以Ⅱ~Ⅲ级为主。恶性组的收缩期峰值流速(Vmax)、阻力指数(RI)、搏动指数(PI)分别为(28.2±7.3)cm/s、(0.78±0.09)、(1.8±0.3),良性组则分别为(13.5±6.7)cm/s、(0.63±0.07)、(1.2±0.2),差异均有统计学意义(P<0.01)。结论二维超声联合CDFI在乳腺良恶性肿瘤的鉴别诊断中有较高的应用价值。  相似文献   
115.
Summary The contorted hazelnut, Corylus avellana L. f. contorta (Bean) Rehder, is an ornamental tree prized for its twisted trunk and branches. Crosses of normal growth habit cultivars and Contorta, as it is commonly called, produced all normal growth habit seedlings. Sib matings of these normal seedlings of Contorta produced offspring in the ratio of 3 normal: 1 contorted, while backcrosses to Contorta segregated 1 normal: 1 contorted. These segregation ratios indicate control of contorted growth by a single recessive gene for which we propose the name twisted and the symbol tw. Progenies segregating simultaneously for growth habit and leaf anthocyanin indicated that the two loci are independent.  相似文献   
116.
Summary Investigations on the inheritance of root color in carrot (Daucus carota L.) were carried out by crossing uniformly colored roots to various tinge type roots, i.e. roots of which the xylem differs in color from the phloem.A single major gene (Y) was found to be responsible for the observed differences in progenies of orange x tinge orange-white (orange referring to phloem color, white to xylem color) crosses. Plants carrying the dominant Y-allele had either white or tinge orange-white roots, whereas plants with orange roots were of the genotype yy. Similarly one major gene (Y 2) determined the segregation found in progenies of orange x yellow crosses. In the latter crosses, plants having the dominant Y 2-allele had either yellow or tinge orange-yellow roots while the recessive would be orange. Variation in phloem color, i.e. differences between white and tinge orange-white or between yellow and tinge orange-yellow, was apparently caused by minor genes, modifiers, gene interactions, or by genes that are not involved in carotenogenesis in a direct way.When both the Y- and Y 2-genes were present, the roots were always white. Usually white roots gave a digenic segregation pattern in the F2 when crossed to orange, but there was some evidence that a third gene (Y 1) was segregating in some crosses. Tinge orange-white x yellow crosses gave approximately the same results as orange x white crosses, confirming that the same Y- and Y 2-genes were segregating.In crosses between orange lines and a light yellow line (RY) certain F1 's appeared to have a light orange xylem and a fairly dark orange phloem, which seems to be some evidence for the existence of recessive yellow. Although almost nothing is known yet about the genetics of RY it is assumed that it still carries a dominant inhibitor gene which may be leaky in heterozygous condition. The value of such a line as an aid in the selection of superior orange lines is discussed.Alpha- and beta-carotene were found to be the major pigments in orange carrot tissue; phytofluene, zetacarotene, gamma-carotene and xanthophylls were shown to be present in smaller amounts. Besides xanthophylls and a small amount of beta-carotene dark yellow carrot tissue appeared to contain an appreciable amount of an unidentified pigment (pigment I). Light yellow and white phloem or xylem tissue were low in total carotenoids.Research supported by the College of Agricultural and Life Sciences and by a grant from the Campbell Soup Company, Camden, New Jersey, USA. The investigation is a portion of a thesis submitted in 1978 as partial fulfillment of the requirements of the PhD degree.  相似文献   
117.
Summary Variation in pigment content of the flour of bread wheats (Triticum aestivum L.) was studied in the progenies of F1 and F2 of three crosses and their reciprocals. Reciprocal differences in pigment content were observed in the F1 and F2 means. Low pigment content was found to be partially dominant or over dominant in the crosses studied. There was evidence of substantial mid-parent F1 heterosis in all crosses and betterparent F1 heterosis in three crosses. In the F2, heritability estimates were moderate to high. The F2 frequency distributions were not normal. Estimation of effective factor pairs indicated the presence of one or two major gene pairs involved in the expression of pigment content in the flour. Action of modifiers was also assumed in one cross and its reciprocal. A factorial approach to metrical character suggested that the F2 segregation ratios of low pigment content to high pigment content were 3:1, 15:1, 13:3 and 9:7 for the different crosses. Utilization of the findings in a wheat breeding program is briefly discussed.  相似文献   
118.
In view of color image characteristic, the paper improves the zero algorithm in the application of concrete algorithm, draws a new algorithm-incomplete scanning method, which is applied to color image compression. The authorsconvert color image from the RGB space into luminance-chrominance YUV space, then compress the converted image to encode/decode. Theoretical analysis and simulation experiment indicate that the compression ratio and encoding/decoding speed are increased, at the sase time the quality of restored image is guaranteed.  相似文献   
119.
栎属4个树种秋冬叶色与生理变化的关系   总被引:2,自引:1,他引:2  
为了研究栎类树种秋冬转色期叶色变化的生理机制,以栎属4个树种——鲜红栎(Quercus coccinea)、纳塔栎(Quercus nuttallii)、沈氏栎(Quercus shumardi)、针栎(Quercus palustris)为试材,测定其秋冬转色期叶绿素、类胡萝卜素、花色素苷3种色素和可溶性糖、可溶性蛋白质含量变化。结果表明:叶绿素a、叶绿素b、总叶绿素含量均呈先快后慢的下降趋势;类胡萝卜素含量鲜红栎和沈氏栎呈现下降-上升-下降的趋势,其他2个树种呈平缓下降的趋势;花色素苷含量呈波动上升趋势;叶绿素a与叶绿素b的比值变化趋势前中期较为平缓,后期迅速下降;鲜红栎的可溶性糖含量为单峰曲线,其他3个树种呈双峰曲线,与花色素苷相关性不显著;蛋白质含量与花色素苷含量呈正相关。  相似文献   
120.
本研究以半年生翠云草盆栽为试验材料,研究不同遮荫处理对翠云草叶色变化的影响。试验设置全光照R0(透光率100%NS)、一层遮荫R1(38%NS)、二层遮荫R2(20%NS)、三层遮荫R3(16%NS)和四层遮荫R4(10%NS)共5个处理。处理3个月后,比较叶片中叶绿素a、叶绿素b、叶绿素a+b、叶绿素a/b、类胡萝卜素、花色素苷、苯丙氨酸解氨酶及可溶性糖含量变化。结果显示,叶绿素含量在3层遮荫处理下最高,叶片表现出特殊的蓝绿色;全光照下,叶绿素含量和花色素苷含量均最低,而类胡萝卜素含量最高,说明叶片受到强光胁迫,是类胡萝卜素而不是花色素苷取代了那部分被破坏的叶绿素,因此叶片表现出红色。方差分析表明,不同遮荫处理对翠云草叶片中叶绿素含量影响极显著,对花色素苷含量影响显著,而对类胡萝卜素含量影响不显著。掌握翠云草叶色在不同遮荫条件下的变化规律,有助于在园林中根据景观需要进行合理配置,创造别具特色的园林植物景观。  相似文献   
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