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71.
Nitrogen balance in barrows fed low-protein diets supplemented with essential amino acids 总被引:3,自引:0,他引:3
D. Deng R.L. Huang T.J. Li G.Y. Wu M.Y. Xie Z.R. Tang P. Kang Y.M. Zhang M.Z. Fan X.F. Kong Z. Ruan H. Xiong Z.Y. Deng Y.-L. Yin 《Livestock Science》2007,109(1-3):220-223
This study was conducted to determine the effect of addition of essential amino acids (EAA) to low-protein diets on N balance in barrows. Thirty barrows (Duroc × Yorkshire) with an initial BW of 36 kg were fed 5 corn- and soybean meal-based diets containing 13.6 to 18.2% crude protein (CP) for 10 d in a randomized complete block design. The 18.2% CP diet was formulated without addition of EAA (Lys, Met or Thr). The other diets contained 13.6 to 16.5% CP and were supplemented with EAA to provide 0.83% true digestible lysine equal to that in the 18.2% CP diet. Fecal, urinary, and total N excretion as well as N retention (g/d) decreased with decreasing dietary CP level (P < 0.01). The apparent digestibility of N was almost the same for the 18.2 and 16.5 CP diets, but the value was 2% higher (P = 0.07) than that for the 13.6% CP diet. These findings indicate that, compared with the 18.2% CP diets, supplementation with three EAA to the lowest-protein diets (13.6 CP) is inadequate for maximum intestinal protein digestion, amino acid absorption, or tissue protein deposition in growing barrows. 相似文献
72.
ZHANG Hui-zhong LI Hai-gang WEI Yi-ping LIU Jin-geng WU Deng CAO Yong-ke WANG Mei 《园艺学报》2006,22(10):2018-2021
AIM: To investigate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and endothelin converting enzymes (ECE) in non-small-cell lung carcinoma (NSCLC), and their relationship with lymphoid metastasis and prognosis.METHODS: Expression of EMMPRIN and ECE in 77 cases of patients with NSCLC was detected immunohistochemically.The relationship of the expression of EMMPRIN and ECE with tumor size, histological type, differentiation, lymphoid metastasis, clinical stage, and prognosis were analyzed.RESULTS: The expressive rate of EMMPRIN and ECE was 66% and 45%, respectively.The expression of EMMPRIN and ECE was associated positively with lymphoid metastasis (both P<0.01, r=0.371 and 0.467, respectively), and inversely with survival time (P<0.01 and P<0.01).No relationship was found in the expression of EMMPRIN and ECE with tumor size, histological type, and differentiation (P>0.05).The expression of EMMPRIN was associated with the expression of HGF in NSCLC (P<0.05, r=0.243).CONCLUSION: The expression of EMMPRIN and ECE is associated with lymphoid metastasis and prognosis in NSCLC.Overexpression of EMMPRIN and ECE implies infavourable prognosis in NSCLC. 相似文献
73.
74.
Gross Anatomy of the Pancreatic Lobes and Ducts in Six Breeds of Domestic Ducks and Six Species of Wild Ducks in China 总被引:1,自引:0,他引:1
J. W. Liu H. Evans P. Larsen D. Pan S. Z. Xu H. C. Dong X. B. Deng B. Wan T. Gi 《Anatomia, histologia, embryologia》1998,27(6):413-417
A previously unreported pancreatic duct was found by Liu (1989) in Pekin ducks. This duct has now been consistently found in six breeds of domestic ducks and six species of wild ducks in China. For purposes of Nomina Anatomica Avium it is hereby called the ‘first pancreatic duct’(Ducius pancreaticus primus) since it enters the duodenum at or near the flexure where the descending duodenum becomes the ascending duodenum. All other pancreatic ducts enter the duodenum later, closer to where it joins the jejunum. This first pancreatic duct drains the caudal extremity of the dorsal lobe of the pancreas and can be easily exteriorized for experimental purposes. Within the parenchyma of the dorsal lobe of the pancreas this duct communicates with the dorsal pancreatic duct. In the present study of the gross anatomy of the pancreatic lobes of domestic and wild Chinese ducks we describe and illustrate variations in position and number of all biliary and pancreatic ducts. 相似文献
75.
76.
Lei Chen Gang Gu Chengxu Wang Zhufeng Chen Wei Yan Man Jin Gang Xie Junli Zhou Xing Wang Deng Xiaoyan Tang 《作物学报(英文版)》2021,(4):750-758
Herbicide resistance in crop plants is valuable for integrated weed management in agriculture. Herbicide resistant rice, in particular, is important to manageme... 相似文献
77.
Chiou-Chu Su Chung-Jan Chang Wen-Jen Yang Shih-Tien Hsu Kuo-Ching Tzeng Fuh-Jyh Jan Wen-Ling Deng 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(2):203-216
Pear leaf scorch, the only Xylella fastidiosa-induced disease reported from Taiwan, was found in area where the variety Hengshan (Pyrus pyrifolia) was grown. Strains of pear leaf scorch Xyl. fastidiosa (XF-PLS) shared similarities to strains of other host origins in the requirement of complex medium and the exhibition of
rippled cell walls, however, recent serological and molecular biology studies showed difference among them. Five strains of
XF-PLS were compared with 20 other strains originally isolated from almond, oleander, pecan, plum, peach, mulberry, grapes,
citrus, coffee, and sycamore by sequence analyses of the 16S rRNA gene and 16S–23S rRNA internal transcribed spacer region
(ITS). When sequences of 16S rRNA gene based on fragment size of 1,537–1,540 bp were compared, the similarity index among
5 XF-PLS strains was 99.3–99.8%, whereas it was 97.8–98.6% between XF-PLS strains and strains from other hosts. When sequences
of 16S–23S rRNA ITS based on fragment size of 510–540 bp were compared, the similarity index among 5 XF-PLS strains was 99.0–100%,
whereas it was 80.7–82% between XF-PLS strains and strains from other hosts. Multiple sequence alignments led to the identification
of 5 polymorphic nucleotides in the 16S rRNA gene among the 25 Xyl. fastidiosa strains, and there were considerable variations in the nucleotide sequences of 16S–23S rRNA ITS between XF-PLS and the other
20 Xyl. fastidiosa strains. The phylogenetic trees revealed that XF-PLS strains were separated from strains of other hosts. Strains of other
hosts were divided into four subgroups: strains from (1) oleander, (2) grape, almond M23 and mulberry, (3) citrus and coffee,
and (4) pecan, peach, plum, sycamore and almond M12. Results indicate that XF-PLS strains were not closely related to the
above-mentioned strains from other hosts and could possibly belong to a new subspecies of Xyl. fastidiosa. 相似文献
78.
不同生长阶段群体数量特征对产草量作用的分析 总被引:8,自引:0,他引:8
在相同的光,温,水,肥条件下,同时对营养生长期的高羊茅和生殖生长期的多年生黑麦草人工草地产草量和群体数量特征的定量关系进行研究。在营养生长期,参数的变异程度小于生殖生长期。营养生长期各因子对产草量直接作用的程度排序这:叶面积指数〉草丛高度〉分蘖密度,生殖生长期为;草丛高度〉叶面积指数〉分蘖密度。 相似文献
79.
The effects of using 100% black spruce (Picea mariana) bark fibers as core layer material accounting for up to 70% of the board and its resin content (between 6 and 10%) on the
properties of three-layer medium-density fiberboard (MDF) were investigated using a full factorial experimental design with
two independent variables and three levels. Five response variables, namely internal bond strength, modulus of rupture, modulus
of elasticity, thickness swelling and water absorption were statistically analyzed using a response surface methodology and
two-way analysis of variance. The effects of the proportion of core layer (bark fibers) and its resin content on panel properties
were significant. All properties studied were positively affected by increasing core layer resin content. The effects of the
proportion of core layer (bark fibers) on mechanical properties and water absorption were negative, but positive on thickness
swelling. Simultaneous optimization of panel properties indicated that at a density of 850 kg/m3, a three-layer MDF with a core layer resin content of 6.5%, a face resin content of 12 and 60% of core layer proportion (spruce
bark fibers) would satisfy the minimum requirements of ANSI standard for 130-grade MDF. Overall, black spruce bark, a major
residue source in the Eastern Canada, should be considered as a supplemental furnish for the core layer materials of a three-layer
MDF. 相似文献
80.
本研究对2014年从新疆额敏县分离到的一株野鸟源H3N8亚型流感病毒A/wild bird/Xinjiang/S3525/2014(H3N8)进行了全基因序列和进化分析。序列分析显示,HA裂解位点序列为~(339)PEKQTR-GLFG~(348),为典型的低致病性禽流感病毒特征,NA基因具有6个潜在的糖基化位点,与病毒株A/mallard/Czech Republic/14333-1K/2011(H3N8)核苷酸高度同源(97.7%)。该毒株的内部基因来源较复杂,其PB1、NP基因分别与A/ruddy shell duck/Mongolia/921C2/2009(H7N1)和A/wild duck/Korea/MHC39-26/2011(H7N9)的同源性最高,其余内部基因与H2、H3、H6、H7等亚型禽流感病毒分离株同源性最高,呈现明显的异源性。除PB2基因外,其余基因片段均来源于野鸟源禽流感病毒。 相似文献