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91.
92.
S A Gusev 《Biulleten' eksperimental'no? biologii i meditsiny》1975,80(7):104-106
Regularities attending the change in the lumen diameter and the area of the endothelial cells were studied in the capillaries of the rat parotid gland during the secretory cycle under conditions of circulatory ischemia. The mean lumen diameter and the area of endothelial cells failed to change during the secretory cycle and during the occlusion of the carotid artery. It is thus supposed that enhanced capillary blood flow during the discharge of saliva could be explained by the growing number of the functioning capillaries. 相似文献
93.
94.
A mathematical model is suggested of the biological system of angular stabilization in space relative to the local vertical using measures whose parameters are near to the parameters of the semicircular canals and otolithic organ of the man. On the basis of computer simulation for physiologically adequate external stimulations contribution of each of measures to the total process of angular stabilization is evaluated. 相似文献
95.
O S Gorbatiuk E I Goufman A A Gusev L K Starosel'tseva I G Akmaev 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(7):105-107
The structural correlates of the cell responses in subnuclei of the hypothalamic paraventricular nuclei (PVN) in fasting and carbohydrate loaded adult male rats were studied using light microscopic morphometric methods. The data obtained revealed difference in responsiveness of the subnuclei studied to alternative shifts in the carbohydrate homeostasis: histophysiological features in five of ten cell-divisions, distinguished in the rat RVN, demonstrated their dependence on impaired carbohydrate homeostasis. 相似文献
96.
Pier?Francesco Palamara Laurent?C. Francioli Peter?R. Wilton Giulio Genovese Alexander Gusev Hilary?K. Finucane Sriram Sankararaman Genome of the Netherlands Consortium Shamil?R. Sunyaev Paul?I.W. de?Bakker John Wakeley Itsik Pe’er Alkes?L. Price 《American journal of human genetics》2015,97(6):775-789
The rate at which human genomes mutate is a central biological parameter that has many implications for our ability to understand demographic and evolutionary phenomena. We present a method for inferring mutation and gene-conversion rates by using the number of sequence differences observed in identical-by-descent (IBD) segments together with a reconstructed model of recent population-size history. This approach is robust to, and can quantify, the presence of substantial genotyping error, as validated in coalescent simulations. We applied the method to 498 trio-phased sequenced Dutch individuals and inferred a point mutation rate of 1.66 × 10−8 per base per generation and a rate of 1.26 × 10−9 for <20 bp indels. By quantifying how estimates varied as a function of allele frequency, we inferred the probability that a site is involved in non-crossover gene conversion as 5.99 × 10−6. We found that recombination does not have observable mutagenic effects after gene conversion is accounted for and that local gene-conversion rates reflect recombination rates. We detected a strong enrichment of recent deleterious variation among mismatching variants found within IBD regions and observed summary statistics of local sharing of IBD segments to closely match previously proposed metrics of background selection; however, we found no significant effects of selection on our mutation-rate estimates. We detected no evidence of strong variation of mutation rates in a number of genomic annotations obtained from several recent studies. Our analysis suggests that a mutation-rate estimate higher than that reported by recent pedigree-based studies should be adopted in the context of DNA-based demographic reconstruction. 相似文献
97.
98.
Mona Navaei-Nigjeh Milad Moloudizargari Maryam Baeeri Mahdi Gholami Nasrin Lotfibakhshaiesh Masoud Soleimani Ebrahim Vasheghani-farahani Jafar AI Mohammad Abdollahi 《Cytotherapy》2018,20(9):1124-1142
Background aims
Adipose tissue–derived mesenchymal stromal cells (AT-MSCs), widely known as multipotent progenitors, release several cytokines that support cell survival and repair. There are in vitro and in vivo studies reporting the regenerative role of AT-MSCs possibly mediated by their protective effects on functional islet cells as well as their capacity to differentiate into insulin-producing cells (IPCs).Methods
On such a basis, our goal in the present study was to use three different models including direct and indirect co-cultures and islet-derived conditioned medium (CM) to differentiate AT-MSCs into IPCs and to illuminate the molecular mechanisms of the beneficial impact of AT-MSCs on pancreatic islet functionality. Furthermore, we combined in vitro co-culture of islets and AT-MSCs with in vivo assessment of islet graft function to assess whether co-transplantation of islets with AT-MSCs can reduce marginal mass required for successful islet transplantation and prolong graft function in a diabetic rat model.Results
Our findings demonstrated that AT-MSCs are suitable for creating a microenvironment favorable for the repair and longevity of the pancreas β cells through the improvement of islet survival and maintenance of cell morphology and insulin secretion due to their potent properties in differentiation. Most importantly, hybrid transplantation of islets with AT-MSCs significantly promoted survival, engraftment and insulin-producing function of the graft and reduced the islet mass required for reversal of diabetes.Conclusions
This strategy might be of therapeutic potential solving the problem of donor islet material loss that currently limits the application of allogeneic islet transplantation as a more widespread therapy for type 1 diabetes. 相似文献99.
【目的】水稻白叶枯病是一种严重危害水稻的细菌性病害,培育抗性品种是治理该病害的重要途径。因此,明确云南水稻材料对检疫性病害水稻白叶枯病的抗性,可以为该病害的防治与监测、水稻栽培的合理布局和良好抗性资源的获取提供依据。【方法】采用剪叶接种法测定云南稻区30个品种对7个不同致病型白叶枯病菌的抗性。【结果】在供试的30个云南水稻品种中,2个品种(玉粳16和JS42糯稻)对7个不同致病型菌株均表现为抗性;15个品种对7个致病型菌株均表现感病;对HEN11、SCYC-6、YN7、YN11、FUJ、YN241和PX099等7个致病型菌株表现抗性的水稻品种分别占26.67%、16.67%、23.33%、13.33%、6.67%、10.00%和20.00%。此外,区试材料的抗性比例高于主栽品种,地方稻未发现抗性品种。【结论】现在生产上的大部分水稻品种对优势致病型病原菌入侵的抵抗能力降低甚至丧失。针对云南地区的优势致病小种FUJ筛选得到2个抗性品种:玉粳16和JS42糯稻。 相似文献
100.
Anna Mamaeva Zorigto Namsaraev Yevhen Maltsev Evgeniy Gusev Maxim Kulikovskiy Maria Petrushkina Alla Filimonova Boris Sorokin Nikita Zotko Vladimir Vinokurov Dmitry Kopitsyn Daria Petrova Andrei Novikov Denis Kuzmin 《Journal of applied phycology》2018,30(4):2237-2246
Manipulation of the nutrient concentration is an inexpensive and efficient method for increasing lipid and TAG accumulation in algal cells. However, high volumetric production requires finding a proper balance between the decrease of biomass production and the increase in the total lipid content. We isolated a strain of green microalga Bracteacoccus bullatus and increased its lipid content from 17 to 59% of biomass dry weight by manipulating of nitrogen and phosphorus content in the medium. The 10-fold reduction of the nitrogen and phosphorus concentration in the medium was the most efficient method of the lipid induction compared to nutrient deplete and high nutrient conditions. The oleic (48–64% mass of total fatty acids) and linoleic (14–24% mass of total fatty acids) acids dominated in the fatty acid profile, thus making this strain a suitable candidate for biodiesel production. 相似文献