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排序方式: 共有117条查询结果,搜索用时 15 毫秒
1.
The effects of protein malnutrition on responsiveness of macrophages to proteosepeptone stimulation and on their chemical
composition were investigated. Relative number of resident macrophages in rat peritoneal cavity was reduced by about 50 %
during 4 weeks on 3 % protein diet. Similarly, decreased migration capacity of the circulating macrophages to the peritoneal
exudate in response to the stimulant, was observed in protein-fasted rat compared to that in the 20 % protein-fed group. Further,
the chemical composition of the isolated elicited cells was determined. Total proteins, sugars, lipids and nucleic acids were
significantly low in the cells isolated from protein-deficient animals, though the cell size was not affected. However, cholesterol:
phospholipid molar ratios were distinctly higher than that in control and increased progressively in the 3 and 8 % protein-fed
animals. The implications of these structural changes in macrophages on their functional capability are discussed 相似文献
2.
近年来,常用未经丙酮固定的、由丁酸和巴豆油激活的B95-8细胞或P3HR-1细胞为靶细胞,检测人血清中EB病毒IgA/MA抗体以早期诊断鼻咽癌,效果良好。但由于B95-8细胞含有多种EB病毒抗原,不能用丙酮固定,需多次离心沉淀,在浮悬状态下检测,技术比较复杂。 相似文献
3.
HAU3是寄主范围很广的放线菌噬菌体。Southern杂交实验表明,HAU3可以整合到吸水链霉菌应城变种10-22和变铅青链霉菌66的突变体ZX1的染色体中,形成溶原,其溶原菌自发释放HAU3,不受热激和紫外线照射的诱导。通过比较HAU3衍生噬粒pIJ8300的DNA酶切片段在加热前、后电泳带谱的区别,将HAU3的cos位点在pIJ8300的图谱上得到了定位。还利用Southern杂交的方法定位了HAU3与宿主形成溶原时附着位点(attP),并利用脉冲电泳技术定位了在变铅青链霉菌ZX7和吸水链霉菌应城变种10-22中形成溶原的附着位点(attB)。这些信息均有利于以HAU3为基础的载体的发展和优化。 相似文献
4.
Molybdate agar was fortified with 0.125% calcium propionate and used for routine isolation and differentiation of a variety of yeasts from mixed floras including large numbers of fungi and actinomycetes inhabiting tropical fruits. The results suggest that this technique could be usefully incorporated in yeast isolation and identification procedures. 相似文献
5.
Dmitry Suplatov Evgeny Kirilin Vakil Takhaveev 《Journal of biomolecular structure & dynamics》2013,31(11):1752-1758
During evolution of proteins from a common ancestor, one functional property can be preserved while others can vary leading to functional diversity. A systematic study of the corresponding adaptive mutations provides a key to one of the most challenging problems of modern structural biology – understanding the impact of amino acid substitutions on protein function. The subfamily-specific positions (SSPs) are conserved within functional subfamilies but are different between them and, therefore, seem to be responsible for functional diversity in protein superfamilies. Consequently, a corresponding method to perform the bioinformatic analysis of sequence and structural data has to be implemented in the common laboratory practice to study the structure–function relationship in proteins and develop novel protein engineering strategies. This paper describes Zebra web server – a powerful remote platform that implements a novel bioinformatic analysis algorithm to study diverse protein families. It is the first application that provides specificity determinants at different levels of functional classification, therefore addressing complex functional diversity of large superfamilies. Statistical analysis is implemented to automatically select a set of highly significant SSPs to be used as hotspots for directed evolution or rational design experiments and analyzed studying the structure–function relationship. Zebra results are provided in two ways – (1) as a single all-in-one parsable text file and (2) as PyMol sessions with structural representation of SSPs. Zebra web server is available at http://biokinet.belozersky.msu.ru/zebra. 相似文献
6.
Densitometric Quantification and Optimization of Polyphenols in Phyllanthus maderaspatensis by HPTLC
UK Ilyas Muhammed Elayadeth-Meethal Mohamed Saheer Kuruniyan Syed Altafuddin Quadri R.S. Rajasree Punnoth Poonkuzhi Naseef 《Saudi Journal of Biological Sciences》2022,29(3):1521
Quantifying and optimizing the polyphenol content of Phyllanthus maderaspatensis was accomplished using a single-solvent HPTLC system. Analyzing hydroalcoholic extracts for kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, we simultaneously quantified and optimized their concentration. In the experiment, the methanol to water ratio (%), temperature (°C), and time of extraction (min) were all optimized using a Box-Behnken statistical design. Kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid were among the dependent variables analyzed. In the HPTLC separation, silica gel 60F254 plates were used, and toluene, ethyl acetate, and formic acid (5:4:1) made up the mobile phase. For kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid, densitometric measurements were carried out using the absorbance mode at 254 nm. Hydroalcoholic extract of P. maderaspatensis contains rutin (0.344), catechin (2.62), gallic acid (0.93), ellagic acid (0.172), quercetin (0.0108) and kaempferol (0.06). Further, it may be affected by more than one factor at a time, resulting in a varying degree of reaction. A negative correlation was found between X1 (extraction time (min)) and X2 (temperature), as well as X1 and X3 (solvent ratios). Taking these characteristics into consideration, the method outlined here is a validated HPTLC method for measuring kaempferol, rutin, ellagic acid, quercetin, catechin, and gallic acid. 相似文献
7.
Background
Cyclic vomiting syndrome (CVS), which is defined by recurrent stereotypical episodes of nausea and vomiting, is a relatively-common disabling condition that is associated with migraine headache and mitochondrial dysfunction. Co-enzyme Q10 (Co-Q) is a nutritional supplement that has demonstrated efficacy in pediatric and adult migraine. It is increasingly used in CVS despite the complete lack of studies to demonstrate its value in treatment 相似文献8.
Effect of simvastatin on fracture healing--an experimental study 总被引:2,自引:0,他引:2
Left femur was osteotomized and fixed with K wire in 21 rabbits. One group was fed simvastatin (120 mg/kg body wt/day) orally, whereas another group without medication served as control. Both groups were assessed radiologically, morphologically, histologically and biomechanically at 4, 8 and 12 weeks. An analysis of various parameters of study showed that simvastatin treated group had improved bone healing at 4 and 8 weeks of follow up, however, the difference was not significant statistically at 12 weeks. So it is concluded that Simvastatin favourably hastened the process of fracture healing in the rabbits at earlier phases. 相似文献
9.
Differential survival and reproduction in colour forms of Philaenus spumarius give new insights to the study of its balanced polymorphism 总被引:1,自引:0,他引:1 下载免费PDF全文
EDUARDO MARABUTO SELÇUK YURTSEVER PAULO A. V. BORGES JOSÉ A. QUARTAU OCTÁVIO S. PAULO SOFIA G. SEABRA 《Ecological Entomology》2015,40(6):759-766
1. Colour polymorphisms are common across animals and are often the result of complex selection regimes. Philaenus spumarius (Linnaeus) (Hemiptera, Aphrophoridae) shows a widely studied dorsal colour polymorphism with several described phenotypes whose variation in their occurrence and frequency, as well as their maintenance across time, have been reported. Several selective influences have been suggested to play a role, but the mechanisms underlying the maintenance of this polymorphism are still poorly understood. 2. To explore the adaptive significance of the colour polymorphism of P. spumarius, an experiment was conducted in captivity under semi‐natural conditions to measure survival, reproductive success, and duration of egg maturation. 3. It was found that there was higher longevity, a higher number of oviposition events, and a higher number of eggs laid by trilineatus phenotype females than by typicus and marginellus, supporting previous reports of an increase in trilineatus frequency during the season. The duration of egg maturation did not differ among phenotypes. 4. The higher longevity and fertility of the trilineatus phenotype may compensate, for example, the higher rate of attack by parasitoids and/or higher solar radiation reflectance in this phenotype, which have already been reported in previous studies, constituting a possible mechanism for the maintenance of this polymorphism. 相似文献
10.