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41.
Pharmacokinetics of kanamycin was studied after its targeted delivery to the liver in autological erythrocyte ghosts on 25 noninbred dogs with experimental acute cholecystitis in comparison to the routine intravenous administration of the antibiotic in solution. Kanamycin concentrations in the tissues of the liver, pancreas, spleen, kidneys and lungs as well as in bile and blood serum were determined by the agar diffusion method 24, 48 and 72 hours after the last administration. It was found that the targeted delivery of kanamycin in blood shadows made it possible to provide high concentrations of the antibiotic for prolonged periods in the liver and biliary ducts and to more efficiently arrest the clinical manifestations of acute cholecystitis as well as normalize the laboratory indices. The data showed that using blood shadows as a reliable system for targeted delivery of antibiotics to the liver was advisable in purulent inflammatory affections of the biliary ducts. 相似文献
42.
S. M. Pershin E. Sh. Ismailov Z. G. Suleimanova Z. N. Abdulmagomedova D. Z. Zagirova 《Biophysics》2014,59(2):334-338
It has been experimentally established that cultivation of yeast cells in depleted, dietary or normal nutrient aqueous solutions enriched with ortho-H2O spin isomers is accompanied by an increase in the amount of carbon dioxide produced by the cells and an increase in their biomass. It has been revealed that the rate of metabolic processes and biological activity depends on the quality of nutrition and enhances in time in both nutrient solutions. In contrast, the reproductive function and the rate of cell division are insusceptible to the components of nutrition, but intensified in a solution enriched with ortho-H2O similar to retardation of aging. The observed effects are discussed in assumption that an increase of a portion of ortho-H2O molecules occurs in the neighborhood of water channels in the cell membrane that let through only monomers of H2O and determine the rate vicinity of metabolic processes. 相似文献
43.
We tried to answer the question to what extent neurons in the tectum of the superior colliculus (SC) of the cat and in regions of the mesencephalic reticular formation (MRF) localized more ventrally are involved in the
control of movements of the limbs. The impulse activity of neurons of the above-mentioned structures was recorded in animals
performing targeted operated food-procuring movements by their forelimbs (pressing the pedal). As was found, neurons with
impulse reactions correlating with forelimb movements are rather numerous in the SC and adjacent MRF, and there are several
groups of neurons, whose impulse responses reached their maxima within different phases of the movements. These were neurons
with peaks of the discharge frequency coinciding with the target-reaching movement, with the moment of touching the pedal,
with pressing the pedal, and with the development of the muscle force counteracting the forced withdrawal of the limb toward
the initial position. Such specific patterns of the responses of different neurons of the SC and neighboring MRF are indicative
of a rather specific involvement of the above structures in the control of forelimb movements in cats.
Neirofiziologiya/Neurophysiology, Vol. 39, No. 3, pp. 245–254, May–June, 2007. 相似文献
44.
The genus Sinotrisus Yin & Li, comprising four species, is redefined and revised. Members of Sinotrisus are often found with ants of the subfamily Formicinae, or in humid forest habitats. The type speciesand three new species are (re-)described and illustrated: Sinotrisus kishimotoi Yin & Nomura, sp. n. (China: Sichuan), Sinotrisus nomurai Yin, Li & Zhao (type species) (China: Zhejing), Sinotrisus sinensis Yin & Nomura, sp. n. (China: Sichuan) and Sinotrisus vietnamensis Yin & Nomura, sp. n. (Vietnam: Lai Chau). A key is included as an aid to distinguishing these species. 相似文献
45.
The somatotropic axis, the control system for growth hormone (GH) secretion and its endogenous factors involved in the regulation of metabolism and energy partitioning, has promising potentials for producing economically valuable traits in farm animals. Here we investigated single nucleotide polymorphisms (SNPs) of the genes of factors involved in the somatotropic axis for growth hormone (GH1), growth hormone receptor (GHR), ghrelin (GHRL), insulin-like growth factor 1 (IGF-I) and leptin (LEP), using polymerase chain reaction–single-strand conformation polymorphism (PCR–SSCP) and DNA sequencing methods in 452 individual Mehraban sheep. A nonradioactive method to allow SSCP detection was used for genomic DNA and PCR amplification of six fragments: exons 4 and 5 of GH1; exon 10 of GH receptor (GHR); exon 1 of ghrelin (GHRL); exon 1 of insulin-like growth factor-I (IGF-I), and exon 3 of leptin (LEP). Polymorphisms were detected in five of the six PCR products. Two electrophoretic patterns were detected for GH1 exon 4. Five conformational patterns were detected for GH1 exon 5 and LEP exon 3, and three for IGF-I exon 1. Only GHR and GHRL were monomorphic. Changes in protein structures due to variable SNPs were also analyzed. The results suggest that Mehraban sheep, a major breed that is important for the animal industry in Middle East countries, has high genetic variability, opening interesting prospects for future selection programs and preservation strategies. 相似文献
46.
Sh. R. Madyarov 《Biochemistry. Biokhimii?a》2014,79(7):687-693
The effects of detergents, trypsin, and bivalent metal ions on production of phosphatidic and lysophosphatidic acids by the action of phospholipase D (PLD) on lecithin and lysolecithin were studied. It was found that these reaction products and dodecyl sulfate ions activate PLD, whereas other anionic detergents are less effective. A protective effect of the functioning enzyme against its hydrolytic inactivation by trypsin was found. Bivalent metal ions can be arranged in the following sequence by their ability to activate PLD in the hydrolysis of lecithin and lysolecithin: Ca2+ > Sr2+ > Ba2+ > Mg2+. These results are considered in relation to a proposed mechanism of activation and functioning of PLD with the participation of clusters of phosphatidates and lysophosphatidates. Such Me2+-induced formation of rafts or microdomains from the products of hydrolysis of phospholipids can rationalize not only PLD activation and self-regulation, but also the action of this mechanism on other components and properties of biomembranes. PLD and other lipolytic enzymes can be classified as lateral vector enzymes. 相似文献
47.
Background impulse activity (BIA) of neuronal elements of the fastigial nucleus (FN) of rat cerebellum were investigated for the first time with the aid of various methods of statistical analysis. A clear predominance of stationary impulse flows (IFs) was discovered, along with irregularities in such flows, variously expressed and including a significant number of realizations of a regular component of impulse activity. Nonstationary IFs constituted a special variety of BIA; they were found in 15% of the total number of neurons investigated. Serial correlation analysis of the durations of interspike intervals (ISIs), both of stationary and nonstationary IFs, allowed us to identify six main varieties of ISI dynamics in the BIA of neurons of the fastigial nucleus. The patterns of recorded IFs and variations in IFs can serve as an adequate indices of the state of cellular activity during intracellular recording from cells of the central nervous system.L. A. Orbeli Institute of Physiology, Armenian Academy of Sciences, Yerevan. Translated from Neirofiziologiya, Vol. 23, No. 4, pp. 441–450, July–August, 1991. 相似文献
48.
Yousry Hawash Laila Sh. Dorgham Ayman S. Al-Hazmi Mohammed S. Al-Ghamdi 《The Korean journal of parasitology》2014,52(5):479-485
Cryptosporidium diarrhea represents a relevant clinical problem in developing countries. In Al-Taif, a city of Saudi Arabia that lies at an altitude of an around 2 km above the sea level, Cryptosporidium infection seems to be undiagnosed in nearly all clinical laboratories. Furthermore, nothing was published regarding Cryptosporidium-associated diarrhea in this area. The objectives of this research were to (1) determine the Cryptosporidium prevalence among patients with diarrhea and (2) to estimate the performances of 3 different diagnostic methods. Total 180 diarrheal fecal samples, 1 sample per patient, were collected between January and August 2013. Samples were screened for Cryptosporidium with modified Zeihl Neelsen (ZN) microscopy, RIDA® Quick lateral flow (LF) immunotest, and a previously published PCR. The Cryptosporidium prevalence rate was 9.4% (17/180), 10% (18/180), and 11.6% (21/180) by microscopy, LF, and PCR test, respectively. Infection was significantly (P=0.004) predominant among children <5 years (22%) followed by children 5-9 years (11.1%). Although infection was higher in males than in females (16.2% males and 8.5% females), the difference was not statistically significant (P=0.11). Compared to PCR, the sensitivity of microscopy and the LF test were 80.9%, 85.7%, respectively. To conclude, high Cryptosporidium-associated diarrhea was found in this area especially in children ≤9 years. The PCR test showed the best performance followed by the LF test and ZN staining microscopy. The primary health care providers in Al-Taif need to be aware of and do testing for this protozoon, particularly for children seen with diarrhea. 相似文献
49.
为了评价胡瓜钝绥螨在我国日光大棚中对茄子上烟粉虱虱的控制作用。笔者研究了在24~34℃下胡瓜钝绥螨以烟粉为猎物时的发育历期,并在我国山东省寿光市的蔬菜基地上开展了利用胡瓜钝绥螨控制日光大棚茄子上烟粉虱的研究与应用。结果表明:胡瓜钝绥螨能够取食烟粉虱的卵、成虫、若虫及伪蛹;利用胡瓜钝绥螨能有效地控制烟粉虱成虫、卵、若虫种群数量的增长。根据胡瓜钝绥螨和烟粉虱的生物学特性,结合大棚茄子栽培过程中的环境条件,笔者提出了在日光大棚中应用胡瓜钝绥螨控制茄子上烟粉虱的策略:(1)在茄子的整个生长季节(250d)中需释放胡瓜钝绥螨4~6次,苗期每次每株释放5~10头,结果期每次每株释放20~40头;(2)释放胡瓜钝绥螨的生防区比常规化防区减少农药使用18次;(3)安装防虫网、适时释放胡瓜钝绥螨是生防成功之关键,生防区配合使用黄板效果更好。 相似文献
50.
Denisova TV Kazeev KSh 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2006,46(1):89-93
The Influence of gamma-radiation by dozes 1, 5, 10 and 20 kGy on enzyme activity of ordinary chemozem were studied. Dynamics of the restoration of the enzyme activity after the influence of gamma-radiation in model experiments in 3, 30, 90 and 180 days was investigated. The doze 1 kGy did no statistically significant influence on the investigated enzymes. Dehydrogenase is more radiosensitive enzyme than catalase. Values of the saccharase activity differed a significant variation so in most cases it has not been registered statistically significant changes. In 90-180 days of the incubation enzymes activity was restored up to control values. Dehydrogenase activity in 180 days in variants with dozes 10 and 20 kGy was restored up to a level of the control, over variants with dozes 1 and 5 kGy--is higher than the control over 78% and 23% accordingly. Saccharase activity in 180 days after the influence of gamma-radiation with a doze 20 kGy was on 61% lower than the control. 相似文献