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51.
热环境对虎斑颈槽蛇卵孵化期、孵化成功率和孵出幼体特征的影响 总被引:2,自引:0,他引:2
用恒温(24、27、30和33C)和波动温度(平均26.1C,范围20.1—32.7C)孵化虎斑颈槽蛇(Rhabdophis tigrinus lateralis)卵,检测热环境对孵化期、孵化成功率和孵出幼体的影响。孵化热环境显著影响孵化期、孵化成功率和胚胎畸形率,对孵出幼体性别无显著影响。孵化期随孵化温度升高而缩短,24、27、30和33C的平均孵化期分别为45.0、32.7、27.3和26.0d,波动温度的平均孵化期为37.9d。33C孵化成功率最低(16.7%),胚胎畸形率最高(100%)。孵出幼体总性比(雌性/雄性=0.6)不显著偏离1:1。孵出幼体的尾长显示两性异形,雄性尾长大于雌性;其它被检幼体特征无显著的两性差异。24、27和30C以及波动温度孵出幼体的所有被检指标均无显著差异。33C孵出幼体的体重和个体大小小于其它热环境中孵出的幼体,并特征性地具有较小的躯干、较大的剩余卵黄。33C中胚胎发育的能耗显著大于其它热环境中胚胎发育的能耗。33(‘孵出幼体的灰分含量较低,但孵出卵卵壳较重。33C孵出幼体不能运动;其它热环境中孵出的幼体在跑道上表现良好,这些幼体的不问断运动的最大距离、每分钟运动距离和每分钟停顿次数无显著的差异。结果表明,持续将虎斑颈槽蛇卵暴露在33C条件下不利于该种胚胎发育并可能对胚胎具有致死性影响,波动温度孵卵有利于拓宽存活孵化温度范围。 相似文献
52.
人谷胱甘肽硫转移酶A1在乳酸乳球菌中的表达及活性研究 总被引:11,自引:0,他引:11
用RTPCR技术从人肝总RNA中分离扩增了人谷胱甘肽硫转移酶A1基因的cDNA序列,克隆至大肠杆菌表达质粒pET23b,采用蛋白表达筛查法及DNA测序证明该cDNA序列完全正确。重组质粒pET23bhgst转化大肠杆菌BL21(DE3),经IPTG诱导获得高效表达的可溶性hGSTA1产物,其表达量约为大肠杆菌可溶性总蛋白的40%。将hGSTA1cDNA亚克隆至乳酸乳球菌表达载体pMG36e,电穿孔法转化乳酸乳球菌MG1363获得hGSTA1乳酸乳球菌表达株。SDSPAGE及Western杂交分析表明该菌株表达预期大小的hGSTA1融合蛋白,经谷胱甘肽琼脂糖亲和层析纯化获得的hGSTA1蛋白具有较高的谷胱甘肽硫转移酶活性。具hGSTA1酶活性的乳酸乳球菌工程菌可望应用于研制防癌保健乳制品。 相似文献
53.
甜荞是异花授粉作物,自然界中的甜荞种质资源多存在生物学混杂现象。每份甜荞种质资源可以分化出若干份新的遗传资源类型,其遗传背景复杂。简化甜荞种质资源的遗传背景,准确描述新品种的亲子代关系和遗传背景一直是世界荞麦工作者面对的技术难题。甜荞种质资源的繁育需要采取隔离措施,实施过程中需要考虑甜荞花粉粒大小、甜荞授粉机制、访问昆虫种类以及种子量多少等。为解决上述问题,本研究建立了以隔离杂交圃、隔离单繁圃、隔离扩繁圃、隔离比较圃和田间试验圃的荞麦繁育新方法——"五圃法",以期开发出不同类型的新的荞麦资源,在育种中可针对性的配制强优势组合,为新品种选育提供种质材料。 相似文献
54.
Xiaohong Yang Dian Teguh Jian-Ping Wu Bo He Thomas Brett Kirk Shengnan Qin Siming Li Honghui Chen Wei Xue Benjamin Ng Shek Man Chim Jennifer Tickner Jiake Xu 《Arthritis research & therapy》2015,17(1)
IntroductionStructural alterations in intra-articular and subchondral compartments are hallmarks of osteoarthritis, a degenerative disease that causes pain and disability in the aging population. Protein kinase C delta (PKC-δ) plays versatile functions in cell growth and differentiation, but its role in the articular cartilage and subchondral bone is not known.MethodsHistological analysis including alcian blue, safranin O staining and fluorochrome labeling were used to reveal structural alterations at the articular cartilage surface and bone–cartilage interface in PKC-δ knockout (KO) mice. The morphology and organization of chondrocytes were studied using confocal microscopy. Glycosaminoglycan content was studied by micromass culture of chondrocytes of PKC-δ KO mice.ResultsWe uncovered atypical structural demarcation between articular cartilage and subchondral bone of PKC-δ KO mice. Histology analyses revealed a thickening of the articular cartilage and calcified bone–cartilage interface, and decreased safranin O staining accompanied by an increase in the number of hypertrophic chondrocytes in the articular cartilage of PKC-δ KO mice. Interestingly, loss of demarcation between articular cartilage and bone was concomitant with irregular chondrocyte morphology and arrangement. Consistently, in vivo calcein labeling assay showed an increased intensity of calcein labeling in the interface of the growth plate and metaphysis in PKC-δ KO mice. Furthermore, in vitro culture of chondrocyte micromass showed a decreased alcian blue staining of chondrocyte micromass in the PKC-δ KO mice, indicative of a reduced level of glycosaminoglycan production.ConclusionsOur data imply a role for PKC-δ in the osteochondral plasticity of the interface between articular cartilage and the osteochondral junction.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0720-4) contains supplementary material, which is available to authorized users. 相似文献55.
56.
Zhenxiang He Chengjiang Ruan Pei Qin Denise M. Seliskar John L. Gallagher 《Ecological Engineering》2003,21(4-5):271-276
Kosteletzkya virginica (L.) Presl. is a perennial dicot halophytic species, that grows in brackish portions of coastal tidal marshes of the mid-Atlantic and southeastern United States. New saline mudflats have been increasing every year in Northern Jiangsu, China. In 1993, we introduced K. virginica (L.) into China from the Halophyte Biotechnology Center (University of Delaware, USA) as a potential species to improve the soil and develop ecologically sound saline agriculture. Our nearly 10 years of experimental research, both in a test garden and in the field, indicated that K. virginica adapts excellently to the heavy saline soils of Jiangsu Province, China. The average seed yield of K. virginica in 2001 at Yancheng was 638 kg/ha from 1-year old seedlings. There were significant variations among individuals from the unselected population of K. virginica on growth, quality, and seed yield traits. There is great potential to increase the seed yield if superior clones are selected. The seed yield of 35 selected individuals was six times greater than that of the average. Four growth traits of K. virginica were found to have a significant correlation with seed yield. However, there was no strong positive or negative correlation among seed quality traits. The mean seed weight and the germination ratio of the 35 selected individuals of K. virginica were 16.36±0.32 g and 76.11±1.82%, respectively. The percentage content of oil and crude protein in the seeds was 11.28±0.67 and 8.17±0.19%, respectively. The percentage of seed vigor of the selected individuals was 99%, as determined by soft X-ray radiography. 相似文献
57.
Feiyu Jia Chongxi Liu Xiangjing Wang Junwei Zhao Qianfeng Liu Ji Zhang Ruixia Gao Wensheng Xiang 《Antonie van Leeuwenhoek》2013,103(2):399-408
A novel endophytic actinomycete, designated strain NEAU-J3T, was isolated from soybean root (Glycine max (L.) Merr) and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain NEAU-J3T fell within the family Micromonosporaceae. The strain was observed to form an extensively branched substrate mycelium, which carried non-motile oval spores with a smooth surface. The cell walls of strain NEAU-J3T were determined to contain meso-diaminopimelic acid and galactose, ribose and glucose were detected as whole-cell sugars. The major menaquinones were determined to be MK-9(H4) and MK-9(H6). The phospholipids detected were phosphatidylcholine and phosphatidylethanolamine. The major cellular fatty acids were determined to be C16:0, C18:1 ω9c, C18:0, C17:0, C17:1 ω7c, anteiso-C17:0, C16:1 ω7c and C15:0. The DNA G + C content was 62.5 mol%. On the basis of the morphological and chemotaxonomic characteristics, phylogenetic analysis and characteristic patterns of 16S rRNA gene signature nucleotides, strain NEAU-J3T is considered to represent a novel species of a new genus within the family Micromonosporaceae, for which the name Wangella harbinensis gen. nov., sp. nov. is proposed. The type strain of Wangella harbinensis is strain NEAU-J3T (=CGMCC 4.7039T = DSM 45747T). 相似文献
58.
59.
目的:用RP-HPLC方法对注射用重组人尿激酶原制剂蛋白含量进行定量分析。方法:用反相C18柱、0.1%TFA水溶液与0.1%乙腈进行梯度洗脱,280nm波长紫外检测器监测;以重组人尿激酶原同质标准品作为对照品,根据进样量和相应的峰面积建立标准曲线方程,将待测定样品的峰面积代入标准曲线方程,可测得蛋白含量。结果:按照方法学验证要求对此方法进行了专属性、检测限、定量限、线形、精密度(重复性、中间精密度)、准确度(回收率)考察,线性范围为9~27μg,回收率在97%以上,RSD2.0%,完全满足对制剂蛋白的定量需求。结论:本方法准确,适用于注射用重组人尿激酶原成品制剂蛋白定量测定。 相似文献
60.