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91.
Investigation of hemolytic activity of leptospirae on solid culture media   总被引:1,自引:0,他引:1  
Results of investigation of hemolytic activity of leptospirae against red blood cells of various animal species on solid culture media using the technique of agar layers are presented. It has been shown that hemolytic properties of pathogenic and saprophytic leptospirae differ with respect to red blood cells of the sheep, the rabbit, the hamster, the albino rat and the albino mouse. Hemolytic activity of leptospirae regarding the erythrocytes of the cattle, the horse and the fowl depends on the strain of leptospirae. The advantage of using solid nutrient media for the determination of hemolytic properties of leptospirae in comparison with liquid media has been demonstrated.  相似文献   
92.
Exposing muskmelon (Cucumis melo L.) cultivar seedlots to N2atmosphere created totally anaerobic conditions which stimulatedethanol production and accumulation in both high and low vigourseeds. However, accumulation of ethanol was consistently higherin the low vigour seeds than in the high vigour ones. In addition,CO2 production under N2 and in air suggests the presence ofan apparent ‘Pasteur effect’ in the low vigour seedsbut not in the high vigour seeds. Acetaldehyde production underN2 was very low and did not seem to be associated with seedvigour, probably because of its nature as an intermediate inethanol production. The fast shift toward ethanol may be dueto the fact that alcohol dehydrogenase, the enzyme which catalyzesthe conversion of acetaldehyde to ethanol, exists in sufficientamounts in the imbibing seeds so that it is not a limiting factorin the conversion to ethanol. Alcohol dehydrogenase activitydid not appear to be related to seed vigour. Key words: Cucumis melo L., Anaerobic respiration, Germination, Seeds.  相似文献   
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转化生长N子TGF—β1和结缔组织生长因子CTGF是骨形成过程中不可或缺的重要生长因子。研究发现TGF-β1和CTGF具有协同生物效应,CTGF可能作为TGF-β1的下游信号发挥作用。本文对近年来TGF-β1/CTGF通路在骨发育与创伤愈合中相关信号转导调控及分子机制研究进行讨论。尤其是对成骨细胞增殖、分化和功能的调控机理进行综述。  相似文献   
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Background  

Comparative sequence analysis of complex loci such as resistance gene analog clusters allows estimating the degree of sequence conservation and mechanisms of divergence at the intraspecies level. In banana (Musa sp.), two diploid wild species Musa acuminata (A genome) and Musa balbisiana (B genome) contribute to the polyploid genome of many cultivars. The M. balbisiana species is associated with vigour and tolerance to pests and disease and little is known on the genome structure and haplotype diversity within this species. Here, we compare two genomic sequences of 253 and 223 kb corresponding to two haplotypes of the RGA08 resistance gene analog locus in M. balbisiana "Pisang Klutuk Wulung" (PKW).  相似文献   
98.
A modified nucleotide on the 3'-side of the anticodon loop of tRNA is one of the most important structure element regulating codon-anticodone interaction on the ribosome owing to the stacking interaction with the stack of codon-anticodon bases. The presence and identity (pyrimidine, purine or modified purine) of this nucleotide has an essential influence on the energy of the stacking interaction on A- and P-sites of the ribosome. There is a significant influence of the 37-modification by itself on the P-site, whereas there is no such one on the A-site of the ribosome. Comparison of binding enthalpies of tRNA interactions on the P- or A-site of the ribosome with the binding enthalpies of the complex of two tRNAs with the complementary anticodones suggests that the ribosome by itself significantly endows in the thermodynamics of codon-anticodon complex formation. It happens by additional ribosomal interactions with the molecule of tRNA or indirectly by the stabilization of codon-anticodon conformation. In addition to the stacking, tRNA binding in the A and P sites is futher stabilized by the interactions involving some magnesium ions. The number of them involved in those interactions strongly depends on the nucleotide identity in the 37-position of tRNA anticodon loop.  相似文献   
99.
Recurrence and progression to higher grade lesions are characteristic behaviorsof gliomas. Though IDH1 mutation frequently occurs and is considered as an early event in gliomagenesis, little is known about its role in the recurrence and progression of gliomas. We therefore analysed IDH1 and IDH2 statusat codon 132 of IDH1 and codon 172 of IDH2 by direct sequencing and anti-IDH1-R132H immunohistochemistry in 53 paired samples and their recurrences, including 29 low- grade gliomas, 16 anaplastic gliomas and 8 Glioblastomas. IDH1/IDH2 mutation was detected in 32 primarytumors, with 25 low- grade gliomas and 6 anaplastic gliomas harboring IDH1 mutation and 1 low- grade glioma harboring IDH2 mutation. All of the paired tumors showed consistent IDH1 and IDH2 status. Patients were analyzed according to IDH1 status and tumor-related factors. Malignant progression at recurrence was noted in 22 gliomas and was not associated with IDH1 mutation. Survival analysis revealed patients with IDH1 mutated gliomas had a significantly longer progression-free survival (PFS) and overall survival (OS). In conclusion, this study demonstrated a strong tendency of IDH1/IDH2 status being consistent during progression of glioma. IDH1 mutation was not a predictive marker for malignant progression and it was a potential prognostic marker for gliomas of Chinese patients.  相似文献   
100.
目的:探讨Orem自理模式在经尿道膀胱肿瘤电切患者护理中的应用,以Orem自护理论作为指导,对膀胱肿瘤患者电切术后实行护理干预,观察Orem自理模式对膀胱肿瘤电切术后患者生活质量及术后复发率的影响。方法:选择2008年10月至2012年6月我科经尿道膀胱肿瘤电切术患者160例随机分为两组,即对照组和实验组,各80例。其中对照组采用术后常规护理,实验组将Orem自理模式贯穿于常规护理的全过程。比较两组患者术后下床活动时间、住院时间、患者对相关知识的掌握情况及患者满意度。结果:实验组患者术后下床活动时间、住院时间、患者对疾病的认知度、患者满意度均明显高于对照组(P〈0.05)。结论iOrem自理模式应用于经尿道膀胱肿瘤电切术后患者的护理,训练患者及家属自我护理技术和能力,不仅能调动和激发经尿道膀胱肿瘤电切患者主观能动性,变“替代护理”为“自我护理”,而且能减少并发症的发生,提高患者的自理能力及生存质量,初步实现了对经尿道膀胱肿瘤电切患者教育的个体化、系统性、连贯性和重复性。  相似文献   
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