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1.
Flying is the main means of locomotion for most avian species, and it requires a series of adaptations of the skeleton and of feather distribution on the wing. Flight type is directly associated with the mechanical constraints during flight, which condition both the morphology and microscopic structure of the bones. Three primary flight styles are adopted by avian species: flapping, gliding, and soaring, with different loads among the main wing bones. The purpose of this study was to evaluate the cross-sectional microstructure of the most important skeletal wing bones, humerus, radius, ulna, and carpometacarpus, in griffon vultures (Gyps fulvus) and greater flamingos (Phoenicopterus roseus). These two species show a flapping and soaring flight style, respectively. Densitometry, morphology, and laminarity index were assessed from the main bones of the wing of 10 griffon vultures and 10 flamingos. Regarding bone mineral content, griffon vultures generally displayed a higher mineral density than flamingos. Regarding the morphology of the crucial wing bones involved in flight, while a very slightly longer humerus was observed in the radius and ulna of flamingos, the ulna in griffons was clearly longer than other bones. The laminarity index was significantly higher in griffons. The results of the present study highlight how the mechanics of different types of flight may affect the biomechanical properties of the wing bones most engaged during flight.  相似文献   
2.
目的采用高速逆流色谱(HSCCC)分离纯化长春花中长春新碱,建立相关工艺条件,为工业生产提供参考数据。方法采用高速逆流色谱仪,氯仿-甲醇-0.3mol.L-1 HCl(4∶3∶2)溶剂体系,上相为固定相,下相为流动相,流动相流速为2.0mL.min-1,紫外检测波长为280nm,主机转速为800r.min-1,恒温循环温度为28℃。结果 HPLC检测HSCCC纯化后长春新碱质量分数为79.7%。结论高速逆流色谱纯化长春花中长春新碱容量大、分离纯度和效率高,避免了有机溶剂的大量使用,适用于工业生产高纯度产品。  相似文献   
3.
We report a 67‐yr‐old woman with hepatitis C–related liver cirrhosis and hepatoma who had developed severe bone marrow suppression after taking Cantharanthus roseus as an alternative anticancer treatment. The patient developed severe pancytopenia with initial presentations of vomiting, diarrhea, oral ulcer, and fever about 1 week after taking 5‐days' course of Cantharanthus roseus. Bone marrow biopsy showed autolysis, which indicated massive necrosis of the hematopoietic cells. There was no malignant cell infiltration. The patient also had severe gastrointestinal disturbances, bacteremia, urinary tract infection, and impaired renal and liver function. Supportive care with broad‐spectrum antibiotics, granulocyte colony‐stimulating factor, repeated blood transfusions, and albumin supplement was given. She recovered and was discharged after 48 days hospitalization. Coadministration of Cantharanthus roseus and cisapride was noted, and these two drugs are both substrates of cytochrome P450 3A4 enzymes (CYP 3A4). Because the vinca alkaloids are extensively metabolized by the liver cytochrome P450 enzymes, poor hepatic function and drug‐herb interaction might predispose the patient to develop the bone marrow toxicity. This case report demonstrated possible effect of oral dose of vinca alkaloids and also hinted that all the substrates and inhibitors of CYP 3A4 have propensity to interfere with metabolism of vinca alkaloids.  相似文献   
4.
以长春花为研究对象,分析其密码子使用偏好性,以期为相关基因的异源表达、基因的预测、物种的进化研究提供指导。该研究以长春花的30 437条蛋白质编码序列为数据来源,对长春花密码子组成和密码子偏性的各项参数进行了计算和统计分析。计算了长春花萜类吲哚生物碱(terpenoid indole alkaloids,TIAs)生物合成途径中25个关键酶基因含有大肠杆菌或酿酒酵母稀有密码子的比例。结果显示,长春花基因的平均GC量为42.47%,密码子第3位碱基平均GC量为35.89%。长春花中共有28个密码子的同义密码子相对使用度(relative synonymous codon usage,RSCU)大于1,其中26个以A或T结尾。25个关键酶基因含有大肠杆菌稀有密码子的比例明显高于酿酒酵母稀有密码子的比例。长春花主要偏爱使用以A和T结尾的密码子;相比于酿酒酵母,其密码子使用特点与大肠杆菌的差异更大,推测酿酒酵母可能是长春花基因更合适的异源表达宿主。  相似文献   
5.

Objective

To develop a novel approach for the green synthesis of silver nanoparticles using aqueous leaves extracts of Catharanthus roseus (C. roseus) Linn. G. Don which has been proven active against malaria parasite Plasmodium falciparum (P. falciparum).

Methods

Characterizations were determined by using ultraviolet-visible (UV-Vis) spectrophotometry, scanning electron microscopy (SEM), energy dispersive X-ray and X-ray diffraction.

Results

SEM showed the formation of silver nanoparticles with an average size of 35–55 nm. X-ray diffraction analysis showed that the particles were crystalline in nature with face centred cubic structure of the bulk silver with the broad peaks at 32.4, 46.4 and 28.0.

Conclusions

It can be concluded that the leaves of C. roseus can be good source for synthesis of silver nanoparticle which shows antiplasmodial activity against P. falciparum. The important outcome of the study will be the development of value added products from medicinal plants C. roseus for biomedical and nanotechnology based industries.  相似文献   
6.
7.
目的研究用复合酶解法从长春花中提取长春碱的中试工艺。方法在小试基础上采用三因素三水平正交实验考察酶解时间、加水量及搅拌转速对结果的影响。结果中试的最佳工艺为酶解pH4.5、纤维素酶用量1.5%、果胶酶用量1%、酶解温度50℃,加水量5倍,搅拌转速40r/min,酶解时间4h。结论搅拌可加快酶介罐中的酶解进程,提高酶解效率。  相似文献   
8.
不同因子对长春花愈伤组织中药用成分积累的影响   总被引:11,自引:0,他引:11       下载免费PDF全文
 目的 研究继代次数、继代龄(继代组织块的年龄)、生长素、金属离子等因子的改变对长春花愈伤组织生长及吲哚生物碱类药用成分积累的影响。方法 测定不同因子的影响下,长春花愈伤组织的鲜重,并对吲哚总碱进行提取、含量测定和比较。结果 随继代次数的增加,长春花愈伤组织中吲哚总碱含量有所下降;20 d继代龄最利于组织生长;2,4-二氯苯氧乙酸的存在对吲哚总碱的积累有一定的抑制作用,但却有利于愈伤组织生长,两种生长素组合比单一的生长素更利于组织生长,也较利于吲哚总碱积累;钙离子浓度为220 mg·L-1,锌离子浓度为8.6哗·L-1时,对提高吲哚总碱产量最有效。结论 继代次数、继代龄、生长素、金属离子对长春花愈伤组织生长及吲哚生物碱类药用成分的积累有较大影响。  相似文献   
9.
目的探讨乙烯利、乙酰水杨酸、色氨酸3种试剂对长春花植株中药用成分积累的影响。方法用不同质量浓度的3种试剂溶液分别处理温室盆栽长春花植株,2d后,测定叶片中的总吲哚生物碱含量,并采用RP-HPLC法测定长春碱和长春质碱的含量。结果3种试剂处理后吲哚总碱、长春碱、长春质碱的积累均有明显的提高,并确定了最适的处理质量浓度。结论3种试剂对长春花植物中吲哚生物碱的产生有明显的促进作用。  相似文献   
10.
长春花内生真菌的分离及其发酵产生药用成分的初步研究   总被引:15,自引:0,他引:15  
首次报道从长春花 Catharanthus roseus (L.) G. Don茎的韧皮部中分离出尖孢镰刀菌Fusariumoxysporum, 为该植物的一种内生真菌, 并用 TLC和 HPLC对该菌的97CG3菌株培养物进行了分析, 初步结果表明该真菌能产生抗癌药长春新碱成分。  相似文献   
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