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1.
A rapid and efficient in vitro plant regeneration method was developed for Matteuccia struthiopteris (L.) Todaro (Ostrich fern). Side shoots, originating in meristems of sectioned rhizomes, were used as explant material. A very high rate of meristem multiplication was achieved by culturing the explants in half-strength MS liquid medium supplemented with 2.0 mg/l N-(4-Pyridyl)-N′-phenylurea (4-PU) and 0.5 mg/l thidiazuron (TDZ). Multiplication of the shoot primordia was faster in suspension culture than on solid medium. Rhizogenesis and growth of regenerants were best achieved on hormone-free one-quarter-strength MS solid medium amended with 0.4% agar and 1.0% activated charcoal. Regenerated plantlets continued to grow after transfer to soil in a phytotron. Received: 19 March 1998 / Revision received: 17 July 1998 / Accepted: 3 August 1998  相似文献   
2.
鸵鸟(Struthiocamelus)属于平胸总目鸟类,雌雄鸵鸟在性成熟前外部形态相同,很难通过外观和形态来鉴定性别,给早期分群饲养造成了很大的困难。实验利用鸵鸟羽毛提取基因组DNA,之后利用EE0.6和CHD基因中2个引物组合对3对已知性别和9只未知性别鸵鸟的性别基因片段进行特异性扩增。结果显示,这对引物组合在雄性鸵鸟的DNA中未扩增出片段,在雌性鸵鸟DNA中扩增出1条片段,可以对鸵鸟的性别作出准确鉴定,从而解决幼雏期鸵鸟难以从外貌上区分其性别的问题。  相似文献   
3.
This study reports the isolation and partial characterisation of the ostrich serpin, α2AP, and its target enzyme, ostrich plasmin, in its active and inactive proenzyme, namely plasminogen, forms. Ostrich α2AP was purified using lysine–Sepharose chromatography, ammonium sulfate fractionation, and Super Q-650S and ostrich LBSI–Sepharose chromatographies. It revealed a Mr of 84 K (thousand) and had one and two N-terminal amino acids in common with 11 of those of human and bovine α2AP, respectively. It showed the largest inhibitory effect on ostrich plasmin, followed by bovine trypsin and plasmin, respectively, and much less plasmin inhibition than bovine aprotinin, but much more so than human α2AP, DFP and EACA. Ostrich plasminogen was highly purified after lysine–Sepharose chromatography and showed a Mr of 92 K, a total of 775 amino acids and its N-terminal sequence showed 53% identity with those of human, rabbit, cat, and ox plasminogens. Ostrich plasmin, obtained by the urokinase-activation of ostrich plasminogen, revealed a Mr of 78 K, a total of 638 amino acids, an N-terminal sequence showing two to four residues identical to five of those of human, cat, dog, rabbit, and ox plasmins, and pH and temperature optima of 8.0 and 40°C, respectively.  相似文献   
4.
The amino-acid sequence of α-amylase isolated from the pancreas of the ostrich, Struthio camelus was determined. The α-amylase (OPA) consisted of 497 amino acid residues with pyroglutamic acid at the N-terminus and no oligosaccharide. Amino acid identity between OPA and chicken, porcine and human pancreatic α-amylases individually, was found to be 88, 82 and 86%, respectively.  相似文献   
5.
魏屹  高星 《人类学学报》2020,39(2):223-235
鸵鸟蛋皮串珠从旧石器时代开始成为人类主要的装饰品类型之一,提供人类行为和认知发展方面的重要线索,至今仍广泛流行于非洲的狩猎采集者社会中,充当个人和群体间信息通讯的媒介。本文将从鸵鸟蛋皮的结构和种属鉴定入手,系统介绍旧石器时代鸵鸟蛋皮串珠的发现,及民族学记录中鸵鸟蛋皮串珠的制作与使用,并对20世纪以来有关鸵鸟蛋皮串珠的考古学研究作以概述,以期对我国考古学的相关研究提供有价值的信息与帮助。  相似文献   
6.
A myofibril-bound serine protease (MBSP) was partially purified from ostrich (Struthio camelus) skeletal muscle. MBSP was dissociated from the myofibrillar fraction by ethylene glycol treatment at pH 8.5, followed by partial purification via Toyopearl Super Q 650 S and p-aminobenzamidine column chromatographies. Ostrich MBSP revealed a major protein band of approximately 21 kDa on SDS-PAGE, showing proteolytic activity after casein zymography. Optima pH and temperature of ostrich MBSP were 8 and 40 °C, respectively. Substrate specificity analysis revealed that the enzyme cleaved synthetic fluorogenic substrates at the carboxyl side of arginine residues. Kinetic parameters (Km and Vmax values) were calculated from Lineweaver–Burk plots. The kinetic characteristics of ostrich MBSP were compared to values obtained for commercial bovine trypsin in this study, as well as those obtained for MBSP from mouse and various fish species. The results suggest that ostrich MBSP is a tryptic-like serine protease. Ostrich MBSP exhibited low sequence identity to commercial bovine trypsin (44%), MBSP from lizard fish skeletal muscle (33%) and trypsinogen from ostrich pancreas (22%).  相似文献   
7.
Two categories of behaviour involving lateralized posture were observed in semi-natural conditions in ostriches (Struthio camelus). Observing preferences for left or right foot, both in the forward foot posture (the foot standing in front at rest) and the starting foot used to initiate locomotion, a population-level right-foot preference was shown for the whole group and for each of the three age ranges considered (chick, young and adult). Ostriches are known to rely upon a lateralized behaviour during hatching (using their right foot to break the egg shell) suggesting the hypothesis that the precocious motor laterality observed at hatching might stand as a precursor of limb preference later in development, as already observed in other avian species.  相似文献   
8.
A caffeic acid derivative was isolated from Matteuccia struthiopteris (ostrich fern) as a major radical scavenger. The compound consisted of caffeic acid and L-homoserine. NMR and MS analysis revealed the structure as L-O-caffeoylhomoserine.  相似文献   
9.
We measured oxygen consumption ( ) and carbon dioxide emission ( ) rates, air-cell gas partial pressures of oxygen (PAO2) and CO2 (PACO2), eggshell water vapour conductance and energy content of the ostrich (Struthio camelus) egg, ‘true hatchling’ and residual yolk, and calculated RQ and total oxygen consumption ( ) for ostrich eggs incubated at 36.5°C and 25% relative humidity. The pattern showed a drop of approximately 5% before internal pipping. just prior to internal pipping agrees with allometric calculations. Despite the higher incubation temperature compared to other studies, and the resultant shorter incubation duration (42 days), (91.7 l kg−1) was similar to a previously reported value. RQ values during the second half of incubation (approx. 0.68) were lower than expected for lipid catabolism. Prior to internal pipping, PAO2 and PACO2 were 98 and 48.3 torr (13.1 and 6.4 kPa), respectively. The growth pattern of the ostrich embryo is different from the typical precocial pattern, showing a time delay in the rapid growth phase. As a result, the lowered overall energy expenditure for tissue maintenance, as compared to other species, is reflected in the low yolk utilization and high residual yolk fraction of the whole hatchling dry mass. These could also result from the relatively short incubation period of the ostrich egg, thereby evading desiccation by excess water loss.  相似文献   
10.
This work reports the purification and biochemical characterization of angiotensin I-converting enzyme (ACE) from ostrich (Struthio camelus) lung. The molecular weight of the purified enzyme was approximately evaluated to be 200 kDa and the maximum enzyme activity was observed at pH 7.5. The enzyme activity was increased by detergents of Triton X-100 (0.01%), cetyltrimethylammonium bromide (CTAB) (0.1 and 1 mM) and sodium dodecyl sulfate (SDS) (0.1 mM), while decreased by Triton X-100 (1% and 10%) and SDS (1 mM and 10 mM). The secondary and tertiary structure and activity of ACE in the absence and presence of trifluoroethanol (TFE) were investigated using circular dichroism, fluorescence quenching and UV–visible spectroscopy, respectively. Our results revealed that TFE stabilizes ACE at low concentrations, while acts as a denaturant at higher concentration (20%). The Km, Kcat and Kcat/Km values of ostrich ACE towards FAPGG were 0.8 × 10?4 M, 59,240 min?1 and 74 × 107 min?1 M?1, respectively. The values of IC50 and Ki for captopril were determined to be 36.5 nM and 16.6 nM, respectively. In conclusion, ostrich lung ACE is a new enzyme which could be employed as a candidate for studying ACE structure and its natural or synthetic inhibitors.  相似文献   
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