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21.
Tikhonov A Kuz'minov A Poletov N Minbaev Sh Poliakova N 《Vestnik rentgenologii i radiologii》2001,(4):43-47
The paper discusses whether X-ray study of patients with perineal fistulas is required and justified. The main reason is that there is a diversity of diseases which display the same signs as paraproctitis. Of 426 examinees, perineal fistulas were mainly caused by chronic paraproctitis in 85% and by other various diseases showing the similar symptoms in 15%. The basic studies of these patients included fistulography made in 300 patients with external fistulas and proctofistulography performed in 126 patients with incomplete internal fistulas. Comparing the data of X-ray study with those of clinical and morphological ones showed the sensitivity of the former to be 94.5%. Based on the results of their own observations, the authors defined indications for fistulography or proctofistulography. In addition to the analysis of the findings, they present the main points of differential X-ray diagnosis of different diseases manifested by perineal fistulas. 相似文献
22.
Onishchenko GG Aĭdinov GT Moskvitina EA Lomov IuM Tikhonov NG Prometnoĭ VI Shvager MM Ryzhkov VIu Savchenko PP Dmitrieva TA Batashev VV Pukhov IuM Pichurina NL Ivanova NG Gavrinev SA Kovalev EV Kipaĭkin VA Pauk VL Emel'ianova ZN Orekhov IV Lipkovich AD Stakheev VV Trepel' VG Usatkin AV Markov VI Borisevich IV Merkulov VA Makhlaĭ AA Vasil'ev NT Mishan'kin BN Vodop'ianov SO Mazrukho TV Badunenko VP 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2000,(2):36-42
The results of the epidemiological analysis of the outbreak of hemorrhagic fever which was caused by Crimean-Congo hemorrhagic fever virus and occurred during the period of July 3-19, 1999, in the Oblivskaya district of Rostov Province are presented. The specific epidemiological features of the outbreak have been determined. The possible versions of the appearance of the focus of infection and the role of Ixodes ticks in the circulation of the infective agent are discussed. 相似文献
23.
Fabrizio Grandi Marcia M Colodel Lidianne N Monteiro João Rafael VP Leão Noeme S Rocha 《BMC veterinary research》2010,6(1):45
Backgroud
Extramedullary hematopoiesis (EMH) is defined as the presence of hematopoietic stem cells such as erythroid and myeloid lineage plus megakaryocytes in extramedullary sites like liver, spleen and lymph nodes and is usually associated with either bone marrow or hematological disorders. Mammary EMH is a rare condition either in human and veterinary medicine and can be associated with benign mixed mammary tumors, similarly to that described in this case. 相似文献24.
Alvarez-Venegas R Sadder M Tikhonov A Avramova Z 《Molecular biology and evolution》2007,24(2):482-497
The presence of Supressor of variegation-Enhanser of zeste-Trithorax (SET) domain genes in bacteria is a current paradigm for lateral genetic exchange between eukaryotes and prokaryotes. Because a major function of SET domain proteins is the chemical modification of chromatin and bacteria do not have chromatin, there is no apparent functional requirement for the existence of bacterial SET domain genes. Consequently, their finding in only a small fraction of pathogenic and symbiotic bacteria was taken as evidence that bacteria have obtained the SET domain genes from their hosts. Furthermore, it was proposed that the products of the genes would, most likely, be involved in bacteria-host interactions. The broadened scope of sequenced bacterial genomes to include also free-living and environmental species provided a larger sample to analyze the bacterial SET domain genes. By phylogenetic analysis, examination of individual chromosomal regions for signs of insertion, and evaluating the chromosomal versus SET domain genes' GC contents, we provide evidence that SET domain genes have existed in the bacterial domain of life independently of eukaryotes. The bacterial genes have undergone an evolution of their own unconnected to the evolution of the eukaryotic SET domain genes. Initial finding of SET domain genes in predominantly pathogenic and symbiotic bacteria resulted, most probably, from a biased sample. However, a lateral transfer of SET domain genes may have occurred between some bacteria and a family of Archaea. A model for the evolution and distribution of SET domain genes in bacteria is proposed. 相似文献
25.
Aleksandrova NP Donina ZhA Tikhonov MA Baranov VM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2007,93(6):670-677
The role of lung receptors in respiratory control during acute head-down tilt (AHDT, -30 degrees) was investigated in anesthetized, tracheostomized rats. The results show that AHDT increased the mechanical respiratory load, slowed inspiratory flow, reduced the end expiratory lung volume, tidal volume and minute ventilation. On the other hand, during AHDT a significant rise in inspiratory swings of oesophageal pressure was recorded indicated a compensatory increase in inspiratory muscle contraction force. These effects were reduced after transaction of the vagus nerve. It was also shown that respiratory response on added mechanical load was reduced during AHDT as compared with the value in horizontal position. This deference disappeared after vagotomy. The data obtained suggested that afferent information from lung receptors take part in compensation of respiratory effects of AHDT. The cause of reduction in respiratory response to loading during AHDT involves weakness of lung reflexes evoked by volume changes. 相似文献
26.
Biophysics - An Erratum to this paper has been published: https://doi.org/10.1134/S0006350922330016 相似文献
27.
A. V. Tikhonov A. V. Nedoluzhko V. V. Martynov D. B. Dorokhov 《Russian Journal of Genetics》2011,47(3):295-299
Data are presented on the genetic diversity and spatial structure of the natural wild soybean population from the neighborhood
of the settlement of Ekaterinovka in Primorskii krai and on the relationship between the genetic structure of this population
and its spatial organization. These data are discussed in comparison with the results of studies of wild soybean populations
in the Far East region of the Russian Federation and China. Recommendations are given concerning the collection of genetic
wild soybean resources. 相似文献
28.
29.
Donina ZhA Lavrova IN Tikhonov MA Kotov AN Kolesnikov VI Baranov VM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2005,91(9):1091-1096
In ground-based model of the hemodynamics effects of weightlessness, the intersystem relation of breathing and circulation was investigated during inspiration and expiration separately in anesthetized catz. It's shown that the dynamics of central venous pressure, esophageal pressure and filling pressure of the heart during inspiration in supine and head-down tilt position has obvious similarity to those which hypothetically can be present in microgravity. The results suggest that intrathoracic hemodynamics during inspiration in supine and head-down position may be an adequate ground model for investigation of weightlessness influences on intrathoracic circulation. 相似文献
30.
Extracellular human immunodeficiency virus-1 (HIV-1) Tat protein and Tat-derived peptides are biologically active but mechanisms of Tat processing are not known. Within the highly conserved basic region of HIV-1 Tat protein (amino acids, a.a. 48-56), we identified two putative furin cleavage sites and showed that Tat protein was cleaved in vitro at the second site, RQRR\ (a.a. 53-56\). This in vitro cleavage was blocked by a monoclonal antibody that binds near the cleavage site or by the furin inhibitor alpha-1 PDX. Monocytoid cells rich in furin also degraded Tat and this process was slowed by the furin inhibitor or the specific monoclonal antibody. Furin processing did not affect the rates for Tat uptake and nuclear accumulation in HeLa or Jurkat cells, but the transactivation activity was greatly reduced. Furin processing is a likely mechanism for inactivating extracellular HIV-1 Tat protein. 相似文献