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71.
Gerasimov IG 《Uspekhi fiziologicheskikh nauk》2011,42(2):90-96
The concept "functional state" is discussing with attraction notion about fundamental components of live organism: substance, structure, production of energy and information, entropy. In the specified terms is giving working definition of functional condition. From such of positions the normal functional state, and its making--physiological state and psychological state, is considered. 相似文献
72.
Juan Manuel Herrero-Medrano Hendrik-Jan Megens Martien AM Groenen Mirte Bosse Miguel Pérez-Enciso Richard PMA Crooijmans 《BMC genomics》2014,15(1)
Background
A major concern in conservation genetics is to maintain the genetic diversity of populations. Genetic variation in livestock species is threatened by the progressive marginalisation of local breeds in benefit of high-output pigs worldwide. We used high-density SNP and re-sequencing data to assess genetic diversity of local pig breeds from Europe. In addition, we re-sequenced pigs from commercial breeds to identify potential candidate mutations responsible for phenotypic divergence among these groups of breeds.Results
Our results point out some local breeds with low genetic diversity, whose genome shows a high proportion of regions of homozygosis (>50%) and that harbour a large number of potentially damaging mutations. We also observed a high correlation between genetic diversity estimates using high-density SNP data and Next Generation Sequencing data (r = 0.96 at individual level). The study of non-synonymous SNPs that were fixed in commercial breeds and also in any local breed, but with different allele, revealed 99 non-synonymous SNPs affecting 65 genes. Candidate mutations that may underlie differences in the adaptation to the environment were exemplified by the genes AZGP1 and TAS2R40. We also observed that highly productive breeds may have lost advantageous genotypes within genes involve in immune response – e.g. IL12RB2 and STAB1–, probably as a result of strong artificial in the intensive production systems in pig.Conclusions
The high correlation between genetic diversity computed with the 60K SNP and whole genome re-sequence data indicates that the Porcine 60K SNP Beadchip provides reliable estimates of genomic diversity in European pig populations despite the expected bias. Moreover, this analysis gave insights for strategies to the genetic characterization of local breeds. The comparison between re-sequenced local pigs and re-sequenced commercial pigs made it possible to report candidate mutations to be responsible for phenotypic divergence among those groups of breeds. This study highlights the importance of low input breeds as a valuable genetic reservoir for the pig production industry. However, the high levels of ROHs, inbreeding and potentially damaging mutations emphasize the importance of the genetic characterization of local breeds to preserve their genomic variability.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-601) contains supplementary material, which is available to authorized users. 相似文献73.
Ana C. Coan Brunno M. Campos Clarissa L. Yasuda Bruno Y. Kubota Felipe PG. Bergo Carlos AM. Guerreiro Fernando Cendes 《PloS one》2014,9(1)
Objective
Patients with temporal lobe epilepsy (TLE) with hippocampal sclerosis (HS) have diffuse subtle gray matter (GM) atrophy detectable by MRI quantification analyses. However, it is not clear whether the etiology and seizure frequency are associated with this atrophy. We aimed to evaluate the occurrence of GM atrophy and the influence of seizure frequency in patients with TLE and either normal MRI (TLE-NL) or MRI signs of HS (TLE-HS).Methods
We evaluated a group of 172 consecutive patients with unilateral TLE-HS or TLE-NL as defined by hippocampal volumetry and signal quantification (122 TLE-HS and 50 TLE-NL) plus a group of 82 healthy individuals. Voxel-based morphometry was performed with VBM8/SPM8 in 3T MRIs. Patients with up to three complex partial seizures and no generalized tonic-clonic seizures in the previous year were considered to have infrequent seizures. Those who did not fulfill these criteria were considered to have frequent seizures.Results
Patients with TLE-HS had more pronounced GM atrophy, including the ipsilateral mesial temporal structures, temporal lobe, bilateral thalami and pre/post-central gyri. Patients with TLE-NL had more subtle GM atrophy, including the ipsilateral orbitofrontal cortex, bilateral thalami and pre/post-central gyri. Both TLE-HS and TLE-NL showed increased GM volume in the contralateral pons. TLE-HS patients with frequent seizures had more pronounced GM atrophy in extra-temporal regions than TLE-HS with infrequent seizures. Patients with TLE-NL and infrequent seizures had no detectable GM atrophy. In both TLE-HS and TLE-NL, the duration of epilepsy correlated with GM atrophy in extra-hippocampal regions.Conclusion
Although a diffuse network GM atrophy occurs in both TLE-HS and TLE-NL, this is strikingly more evident in TLE-HS and in patients with frequent seizures. These findings suggest that neocortical atrophy in TLE is related to the ongoing seizures and epilepsy duration, while thalamic atrophy is more probably related to the original epileptogenic process. 相似文献74.
Salivary gland duct ligation is an alternative to gland excision for treating sialorrhea or reducing salivary gland size prior to tumor excision. Duct ligation also is used as an approach to study salivary gland aging, regeneration, radiotherapy, sialolithiasis and sialadenitis. Reports conflict about the contribution of each salivary cell population to gland size reduction after ductal ligation. Certain cell populations, especially acini, reportedly undergo atrophy, apoptosis and proliferation during reduction of gland size. Acini also have been reported to de-differentiate into ducts. These contradictory results have been attributed to different animal or salivary gland models, or to methods of ligation. We report here a bilateral double ligature technique for rabbit parotid glands with histologic observations at 1, 7, 14, 30, 60 days after ligation. A large battery of special stains and immunohistochemical procedures was employed to define the cell populations. Four stages with overlapping features were observed that led to progressive shutdown of gland activities: 1) marked atrophy of the acinar cells occurred by 14 days, 2) response to and removal of the secretory material trapped in the acinar and ductal lumens mainly between 30 and 60 days, 3) reduction in the number of parenchymal (mostly acinar) cells by apoptosis that occurred mainly between 14–30 days, and 4) maintenance of steady-state at 60 days with a low rate of fluid, protein, and glycoprotein secretion, which greatly decreased the number of leukocytes engaged in the removal of the luminal contents. The main post- ligation characteristics were dilation of ductal and acinar lumens, massive transient infiltration of mostly heterophils (rabbit polymorphonuclear leukocytes), acinar atrophy, and apoptosis of both acinar and ductal cells. Proliferation was uncommon except in the larger ducts. By 30 days, the distribution of myoepithelial cells had spread from exclusively investing the intercalated ducts pre-ligation to surrounding a majority of the residual duct-like structures, many of which clearly were atrophic acini. Thus, both atrophy and apoptosis made major contributions to the post-ligation reduction in gland size. Structures also occurred with both ductal and acinar markers that suggested acini differentiating into ducts. Overall, the reaction to duct ligation proceeded at a considerably slower pace in the rabbit parotid glands than has been reported for the salivary glands of the rat. 相似文献
75.
The main nongenetic factors are revealed which regulate the catalytic activity and substrate specificity of microsomal monooxygenases preinduced by phenobarbital-type xenobiotics (barbituric acid and pyrazolone derivatives). It is shown that a blockage of the primary microsomal metabolism of an inducer is the obligate condition for its inductive effect on the content and activity of cytochrome P-450. On this basis it is practicable to convert the typical monooxygenase substrates into inducers of the enzyme biosynthesis by the blockage of the molecule site subjected to monooxygenation. A model is suggested which shows the phenobarbital participation in the formation of the specific configuration of the active site of cytochrome P-450 synthesized; the latter catalyzes the oxidation of a number of substrates by the way typical of inducer itself. 相似文献
76.
The R-R intervals were measured in 25 female volunteers aged 21–34 years after exposure to lower body negative pressure (LBNP). A number of advantages of information entropy (h) as an index of cardiovascular performance were revealed. With h used as a controlled variable, it was possible to ensure individual targeted changes in the functional state (FS) during LBNP. It was found that an individual exposure to LBNP caused regular changes in h and FS. Equations for targeted changes in human FS were derived.__________Translated from Fiziologiya Cheloveka, Vol. 31, No. 4, 2005, pp. 61–64.Original Russian Text Copyright © 2005 by Gerasimov, Ignatov. 相似文献
77.
The results of methodical work, carried out on the sources of synchrotron radiation (SR) with the aim of using SR as a powerful source of X-rays for studying biopolymer structure, are presented. The questions of monochromatization are considered. The technique designed for photoregistration of diffraction patterns within the wide range of scattering angles is described. X-ray diffraction patterns of feather ceratin, collagen and striated muscle are obtained with exposure periods ten times less than those in the case of X-ray tubes. The high resolution of diffraction lines, the absence of parasitic phone and the presence of reflections within the wide range of scattering angles are characteristic of these patterns. 相似文献
78.
79.
A. V. Krylov D. B. Kosolapov N. G. Kosolapova A. A. Hovsepyan Yu. V. Gerasimov 《Biology Bulletin》2018,45(5):505-511
The appearance of Daphnia (Ctenodaphnia) magna Straus, 1820 in the pelagial of Sevan Lake caused significant changes in the communities of planktonic algae, bacteria, and heterotrophic nanoflagellates. Phytoplankton and nanoflagellates were the most affected by the direct impact of D. magna, and the number and biomass of bacteria increased due to the reduction in the trophic pressure of the protists. It was also facilitated by the increased supply of phosphorus as a result of the activity of the cladocerans, as well as the decrease in the number and biomass of phytoplankton, which competes with heterotrophic bacteria for the nutrients. 相似文献
80.
V. V. Frol'kis D. P. Artemenko V. D. Gerasimov T. A. Dubiley Yu. E. Rushkevich 《Neurophysiology》1995,27(2):98-104
In the experiments performed on adult and aged rats, the effect of morphine on the electrical activity, recorded from the emotion-producing zones of the hypothalamus, the ventromedial nucleus (VMN), and the lateral hypothalamic area (LHA), was studied. In thein vitro experiments, an age-dependent reduction of background impulse activity (BIA) was found in the VMN single neurons, but not in the LHA neurons. Morphine reduced BIA in most of the VMN neurons, but enhanced it in the LHA neurons of adult rats, and enhanced BIA in the neurons of both structures of the aged rats. The inhibitory effect of morphine on the VMN and LHA neurons and its excitatory effect on the LHA neurons decreased with age. In thein vivo experiments, an age-dependent reduction of the background field electrical activity (background electrogram, BEG) was found in the neurons of both emotion-producing zones. Morphine reduced the BEG magnitude in the VMN and LHA more effectively in the aged rats than in the adult rats. The results allow us to suggest that both the opiate regulation of hypothalamic functions and formation of an opiate dependence in the adult rats essentially differ from those in the aged rats.Neirofiziologiya/Neurophysiology, Vol. 27, No. 2, pp. 126–133, March–April, 1995. 相似文献