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N-methyl-D, L-aspartate (NMA) elicited secretion of growth hormone (GH)-releasing hormone from both the hypothalamic-preoptic area and the median eminence that were collected from boars. We suggest that the previously described increase in GH secretion that follows peripheral treatment of swine with NMA is attributable, at least in part, to NMA-stimulated secretion of GH-releasing hormone from the central nervous system. 相似文献
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This review focuses on the effects of freezing storage on the microstructure and baking performance of frozen doughs, and provides an overview of the activities of dough improvers, including emulsifiers, hydrocolloids and other improvers used in frozen dough applications. The overall quality of bread baked from frozen dough deteriorates as the storage of the dough at sub-zero temperatures increases due to several factors which are discussed. Lipid-related emulsifiers such as diacetyl tartaric acid esters of mono and diglycerides and sucrose esters employed as anti-staling agents, dough modifiers, shortening sparing agents, and as improvers for the production of high-protein bread have also been employed in frozen doughs. Hydrocolloids are gaining importance in the baking industry as dough improvers due to their ability to induce structural changes in the main components of wheat flour systems during breadmaking steps and bread storage Their effects in frozen doughs is discussed. Other dough improvers, such as ascorbic acid, honey and green tea extract, are also reviewed in the context of frozen doughs. 相似文献
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黄朝霞 《厦门水产学院学报》2011,(2):141-144
在Lω-空间中引进加强了的ωTi(i=1,2)-分离性等概念,系统地讨论了这些概念的特征性质,得出它们保持了LF拓扑空间中Ti-分离性的主要结论,进而说明加强了的ωTi(i=1,2)-分离性是L-好的推广. 相似文献
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M Fevrier 《Comparative immunology, microbiology and infectious diseases》1985,8(2):159-170
Antibody response to an antigen involves the co-operation between three types of cells: macrophages, T cells and B cells. The cognate interactions between these cells play a fundamental role in the expression of a specific antibody response, but the last is modulated by antigen-nonspecific soluble factors produced either by macrophages or by T cells. Macrophages elaborate a spectrum of molecules modulating the function of lymphoid cells; among them are IL1 and prostaglandins of the E series, which are respectively enhancer and inhibitor of the antibody response in vitro. These molecules alter T cell and B cell activities through different mechanisms involving activation or inhibition of IL2 production, or alteration of cells surface antigens. However, the cellular events following the fixation of soluble factor on its receptors are not known. 相似文献
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Prolonged elevated atmospheric CO2 might alter decomposition. In a 90-day incubation study, we determined the long-term (9 years) impact of elevated CO2 on N mineralization of Lolium perenne and Trifolium repens plant material grown at ambient and elevated CO2 and low- and high-15N fertilizer additions. No significant differences were observed in recovery rates between any of the treatments, except an N addition effect was observed for L. perenne (0.4 versus 0.5% day−1 in high versus low N). The results suggest that elevated CO2 did not change plant N mineralization in any of the soils, because of a surplus of available N in the fertilized and leguminous systems, and because of insignificant plant responses to elevated CO2 in the low soil N availability systems. 相似文献
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对以色列野生二粒小麦(母本)和光稃野燕麦(父本)远缘杂交亲本与后代的核型及进化关系进行了分析。结果表明:母本的染色体长度比为1626,核型公式为2n=4x=28=18m(2SAT)+10sm(2SAT),核型为1A。父本的染色体长度比为2526,核型公式为2n=6x=42=20m(2SAT)+22sm(4SAT),核型类型为2B。以色列野生二粒小麦和光稃野燕麦杂交后代0878株系的染色体数目为42,染色体长度比为1.802,核型公式为2n=6x=42=22m(2SAT)+20sm(2SAT),核型为2A。 0878-1株系的染色体数目为42,染色体长度比为2.057,核型公式为2n=6x=42=38m+4sm(4SAT),核型为2B。由于光稃野燕麦遗传物质渗入到该杂交后代,获得了进化程度高于其母本的普通小麦型小麦新种质。 相似文献
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水磷耦合对小麦耗水特性和子粒产量的影响 总被引:3,自引:1,他引:2
在低磷地力、沙质壤土条件下,选用强筋小麦品种济麦20,设置全生育期不灌水(W0),灌底墒水+拔节水+开花水,每次灌水30 mm (W1)、60 mm(W2)、90 mm (W3) 4个灌溉处理;每个灌溉处理下设置不施磷(P0)、施P2O5105 kg/hm2(P1)、210 kg/hm2(P2)3个施磷量处理,研究了水磷耦合对麦田耗水特性、产量及水分利用率的影响。结果表明,1)在同一磷素水平下,随灌水量增加,小麦总耗水量增大,降水量和土壤供水量占耗水量的比例降低。综合考虑耗水量、产量、收获指数、水分利用率等指标,最优处理为P1W2处理,其次为P1W1处理,其总耗水量分别为435.5 mm、366.0 mm,灌水量、降水量和土壤供水量占耗水量的比例分别为41.3%、39.3%、19.3%和24.6%、46.8%、28.6%;开花至成熟阶段的耗水量占小麦全生育期耗水量的36.9%~43.3%,此阶段两处理的日耗水量、耗水模系数分别为4.6 mm、3.6 mm和42.3%、39.3%。2)施用磷肥,各处理的干物质积累量增加,子粒产量表现为W2、W3W1W0,W2、W3处理之间差异不显著;与不施磷肥的处理比较,显著提高了土壤供水量占总耗水量的比例。3)收获指数和水分利用率均为W1W2W3,P2水平下W1、W2、W3处理的收获指数和水分利用率均低于P1水平。以上结果表明,在本试验条件下,施磷(P2O5)105 kg/hm2(P1)、灌水180 mm(W2)的处理获得高产和较高的水分利用率;施磷(P2O5)105 kg/hm2(P1)、灌水90 mm(W1)的处理获得较高的产量,水分利用率显著高于上述处理,耗水量则显著低于上述处理,可供生产中水资源不足的情况下参考。 相似文献