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排序方式: 共有210条查询结果,搜索用时 31 毫秒
91.
Rice flour (37% moisture content) was used to examine the effects of feed rate and screw speed on the specific energy input during single-screw extrusion cooking. Torque, raised by decreasing screw speed or increasing feed rate, was found to be a power law function of the ratio of feed rate to screw speed (Fr/Ss) with r2 > 0.94. Specific mechanical energy (SME) calculated from torque also was a power law function of Fr/Ss with r2 >0.84 and negative power law indices. The SME obtained was in the 225–481 kJ/kg range. Thus the extruder can be considered low shear. Increasing SME raised the die temperature and decreased both intrinsic viscosity and water absorption index (WAI). The degree of gelatinization and intrinsic viscosity of extrudates also were power law functions of Fr/Ss. The intrinsic viscosity correlated well with the degree of gelatinization, WAI, and cooking loss, and appeared to be a good index of the extrudate properties. Different screw profiles also affect torque measurement. 相似文献
92.
Pengcheng Wang Chiafen Yeh Jiang Chang Hongyan Yao Yiqiang Fu Chengte Yao Xiao Wang Shouhsien Li Zhengwang Zhang 《中国鸟类》2021,(2):227-236
Background: Understanding how species diversify is a long-standing question in biology. The allopatric speciation model is a classic hypothesis to explain the s... 相似文献
93.
94.
Lin LC Yeh CT Kuo CC Lee CM Yen GC Wang LS Wu CH Yang WC Wu AT 《Journal of agricultural and food chemistry》2012,60(28):7031-7039
Sulforaphane (SFN) has been indicated for the prevention and suppression of tumorigenesis in solid tumors. Herein, we evaluated SFN's effects on imatinib (IM)-resistant leukemia stem cells (LSCs). CD34(+)/CD38(-) and CD34(+)/CD38(+) LSCs were isolated from KU812 cell line flowcytometrically. Isolated LSCs showed high expression of Oct4, CD133, β-catenin, and Sox2 and IM resistance. Differentially, CD34(+)/CD38(-) LSCs demonstrated higher BCR-ABL and β-catenin expression and imatinib (IM) resistance than CD34(+)/CD38(+) counterparts. IM and SFN combined treatment sensitized CD34(+)/CD38(-) LSCs and induced apoptosis, shown by increased caspase 3, PARP, and Bax while decreased Bcl-2 expression. Additionally, the combined treatment reduced BCR-ABL and β-catenin and MDR-1 protein expression. Mechanistically, IM and SFN combined treatment resensitized LSCs by inducing intracellular reactive oxygen species (ROS). Importantly, β-catenin-silenced LSCs exhibited reduced glutathione S-transferase pi 1 (GSTP1) expression and intracellular GSH level, which led to increased sensitivity toward IM and SFN. We demonstrated that IM and SFN combined treatment effectively eliminated CD34(+)/CD38(-) LSCs. Since SFN has been shown well tolerated in both animals and human, this regimen could be considered for clinical trials. 相似文献
95.
The characteristic strength properties of structural glulam connections assembled with self-tapping screws were examined following the ASTM testing procedure in the study. Four screw types with various numbers were designated at each connection of the beam–girder structure with different nailing schedules. The results indicated that the maximum load capacity and dissipated energy of a connection fastened with 10-mm self-tapping screws were higher than those with 8-mm screws. And, the screws with both double-threaded sections and fully threaded shanks were higher than those of single-threaded screws. An improvement on the initial stiffness of a connection was found when the number of self-tapping screws increased. The connections assembled with the toe-nailing approach from the beam’s bottom surface provided higher maximum loading capacity, medium initial stiffness, and a larger ductility factor, resulting in higher dissipated energy with less fragile failure. The derived allowable loading values for a beam–girder connection fastened with self-tapping screws using the face-nailing approach were close to the code values for bolted and pinned connections. And, a toe-nailing approach provided higher allowable loads for connections than using a face-nail approach. 相似文献
96.
Hsieh CW Liu LK Yeh SH Chen CF Lin HI Sung HY Wang AY 《Journal of agricultural and food chemistry》2006,54(8):3101-3107
Three Bo beta fruct cDNAs encoding acid invertases were cloned from shoots of the green bamboo Bambusa oldhamii. On the basis of the amino acid sequences of their products and phylogenetic analyses, Bo beta fruct1 and Bo beta fruct2 were determined to encode cell wall invertases, whereas Bo beta fruct3encodes a vacuolar invertase. The recombinant proteins encoded by Bo beta fruct2 and Bo beta fruct3 were produced in Pichia pastoris and purified to near homogeneity using ammonium sulfate fractionation and immobilized metal affinity chromatography. The pH optima, pI values, and substrate specificities of the isolated enzymes were consistent with those of plant cell wall or vacuolar invertases. The growth-dependent expression of Bo beta fruct1 and Bo beta fruct2 in the base regions of shoots underscores their roles in sucrose unloading and providing substrates for shoot growth. Its high sucrose affinity suggests that the Bo beta fruct2-encoded enzyme is important for maintaining the sucrose gradient between source and sink organs, while the predominant expression of Bo beta fruct3 in regions of active cell differentiation and expansion suggests functions in osmoregulation and cell enlargement. 相似文献
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98.
Tariq Mahmood Muhammad H. Rahman Gary R. Stringam Francis Yeh Allen G. Good 《Euphytica》2007,154(1-2):101-111
A doubled haploid population of Brassica juncea, developed from a cross between two parental lines differing for days to maturity, was used to study the efficiency of indirect
selection for a primary trait through selection of secondary trait(s) over direct selection for the primary trait when quantitative
trait loci information is available for both primary and secondary traits, and applied. Days to maturity was considered as
primary trait, while days to first flowering, days to end of flowering, flowering period and plant height were considered
as secondary traits. An RFLP linkage map was employed for QTL analysis of maturity and maturity-determinant traits, and a
stable QTL B6 simultaneously affecting these two types of traits was identified. This linked QTL explained 11.7% phenotypic
variation for days to maturity, 20.7% variation for days to first flowering, 24.3% variation for days to end of flowering
and 14.4% variation for plant height. Phenotypic evaluation of maturity and/or maturity-determinant traits, viz. days to first
flowering, days to end of flowering and plant height revealed that limited genetic advance for early maturity can be achieved
through phenotypic selection of the primary and/or the secondary trait(s). However, the estimates of genetic advance for early
maturity based on combined phenotypic evaluation and linked QTL data was found to be, at least, three times higher compared
to genetic advance based on phenotypic evaluation only, demonstrating the potential of marker-assisted selection in breeding
for early maturity in B. juncea. 相似文献
99.
Mycelia from Antrodia camphorata in Submerged culture induce apoptosis of human hepatoma HepG2 cells possibly through regulation of Fas pathway 总被引:2,自引:0,他引:2
The objective of this study was to investigate the antiproliferative effect and the mechanism of the methanol extracts of mycelia (MEM) form Antrodia camphorata in submerged culture toward HepG2 cells. The results showed that MEM-induced cell apoptosis involved up-regulation of Fas and down-regulation of Bcl-2, DR3, DR4, TNFRI, and TNFRII in HepG2 cells, while no changes on the levels of Bax, Bid, Bad, and Bak protein were observed. On the basis of these results, the involvement of the Fas/Fas ligand (FasL) death-receptor pathway, in MEM-induced apoptosis in HepG2 cells, was investigated. The apoptosis inducing activity was significantly enhanced by a Fas activator and inhibited by a Fas antagonist. To know about the effect of MEM on the activation of the apoptotic pathway, the adenovirus transfected with Bcl-2 was infected on HepG2 cells. The data showed that the percentage of apoptotic cells induced by MEM in Bcl-2-infected HepG2 (Bcl-2 overexpression) was not significantly different from that of uninfected HepG2. These results demonstrate that MEM induces HepG2 apoptosis through inhibition of cell growth and up-regulation of Fas/FasL to activate the pathway of caspase-3 and -8 cascades. 相似文献
100.