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81.
82.
我国木梳素以小叶黄杨、楠木、枣木、梨木等树种为制梳材料。由于人口膨胀,木梳需求量巨增,制梳原材料渐已匮乏,绵延1 500多年的传统木梳手工艺文化正面临消亡的威胁。笔者选择速生树种——意杨为制梳材料,按木梳实用功能和产业经济的实际需求,对意杨压缩木进行一般物理特性试验,对其木梳制品进行实用和成本分析,最终确定50%左右的意杨压缩木完全能替代木梳传统原材料。 相似文献
83.
杉木人工林地力衰退研究概述 总被引:6,自引:0,他引:6
介绍了我国杉木人工林地力衰退的现状,从森林土壤条件、杉木人工林的营养循环特点和人为经营措施等方面分析了导致杉木人工林地力衰退的原因,提出营建人工复层林、林地施肥、适当延长轮伐期,加强植被管理和进行定位观测等措施防止地力衰退。 相似文献
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Casmara patrona is one of the main borer pests damaging Camellia oleifera in China. Few reports about this insect were published. The life history, biological characteristics and natural enemies of C. patrona were investigated through field survey and laboratory observation in this study. The results showed that C. patrona had one generation in one year or two years, and overwintered as 3rd-5th instar larva in Zhejiang Province. About 88 percent of larvae began to pupate in early May, and the rest kept feeding till the next year. The adults could be observed from early June to early July, and the peak of emergence occurred in late June. The adults began to oviposit in late June and terminated in early July. The eggs started hatching in early July, and then the larvae bored into the branch to feed. The entrance holes of the larvae distributed predominately in the middle of the eastern and southern part of C. oleifera tree. The larva had five instars, and there were 10-50 days when the larva did not feed between consecutive instars. 相似文献
88.
Mohamed M’BAYE Guohua HUA Hamid Ali KHAN Liguo YANG 《The Journal of reproduction and development》2015,61(5):391-397
Inhibins are members of the TGFβ superfamily and act as suppressors
of follicle stimulating hormone (FSH) secretion from pituitary glands
via a negative feedback mechanism to regulate folliculogenesis. In
this study, the INHBB gene was knocked down by three
RNAi-Ready pSIREN-RetroQ-ZsGreen vector- mediated recombinant plasmids
to explore the effects of INHBB silencing on
granulosa cell (GC) cell cycle, apoptosis and steroid production
in vitro. Quantitative real-time polymerase chain
reaction, Western blot, flow cytometry and ELISA were performed to
evaluate the role of INHBB in the mouse GC cell
cycle, apoptosis and steroid production in vitro. The
results showed that the relative mRNA and protein expression of
INHBB in mouse GCs can be significantly reduced by
RNAi with pshRNA-B1, pshRNA-B2 and pshRNA-B3 plasmids, with pshRNA-B3
having the best knockdown efficiency. Downregulation of the expression
of INHBB significantly arrests cells in the G1 phase
of the cell cycle and increases the apoptosis rate in GCs. This was
further confirmed by downregulation of the protein expressions of
Cyclin D1, Cyclin E and Bcl2, while the protein expression of Bax was
upregulated. In addition, specific downregulation of
INHBB markedly decreased the concentration of
estradiol and progesterone, which was further validated by the
decrease in the mRNA levels of CYP19A1and
CYP11A1. These findings suggest that inhibin βB is
important in the regulation of apoptosis and cell cycle progression in
granulosa cells. Furthermore, the inhibin βB subunit has a role in the
regulation of steroid hormone biosynthesis. Evidence is accumulating
to support the concept that inhibin βB is physiologically essential
for early folliculogenesis in the mouse. 相似文献
89.
This experiment was intend to study the changes of long non-coding RNA (H19) expression levels in skeletal muscle development and regeneration,and lay the foundation of its mechanism reach in skeletal muscle development.C2C12 cell line and ICR mice were used as experimental material,bioinformatics assay was used to exploit its non-coding character and low conservatism in different species,and the expressions of H19 in C2C12 cell differentiation,skeletal muscle development and the phase of muscle regeneration were detected by quantitative Real-time PCR (qRT-PCR).The results showed that,H19 expression levels in postnatal mouse skeletal muscle decreased with increasing age;during C2C12 cell differentiation,H19 mRNA increased gradually,and then maintained a high level;The expression of H19 was maintained at a high level through days 4 to 6 after injury.In consideration of its express character in C2C12 cell differentiation and skeletal muscle damage repair model,H19 may play an important role in promoting myogenesis and skeletal muscle regeneration. 相似文献
90.
【目的】 筛选具有诱导番茄系统抗性的促生菌并验证其对加工番茄早疫病、灰霉病的防效,为新疆加工番茄病害的生物防治提供理论依据和菌种资源。【方法】 采用稀释涂布法,分离番茄等作物的根部土壤细菌,以无菌生理盐水和稀释至104倍数未接菌的NB培养基为空白对照,利用发芽实验初筛加工番茄促生菌;用菌株发酵液灌根处理加工番茄幼苗,以清水处理为空白对照,测量叶片中茉莉酸含量,复筛系统抗性诱导菌株,分别挑战接种番茄早疫病、灰霉病病原菌,统计疫情指数和诱抗效果。测定菌株16S rDNA序列,初步进行菌种鉴定。【结果】 共分离到147株细菌,筛选得到19株显著(P<0.05)促进加工番茄种子萌发、增加根长的促生菌,有4株促生菌显著(P<0.05)提高加工番茄叶片中茉莉酸含量,防病验证最终得到3株能同时有效防治加工番茄早疫病、灰霉病的菌株,诱抗防效在27.59%~39.44%。菌株FY10、FY12、FY93鉴定为Bacillus atrophaeus,Pseudomonas wadenswilerensis和Bacillus pumilus。【结论】 获得3株具有系统抗性诱导功能且有效防治加工番茄早疫病、灰霉病的促生菌。 相似文献