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2.
L V Antonova A A Kamenski? T I Vlasova N Iu Sarycheva V N Nezavibat'ko 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(11):569-571
Heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro (ACTH4-10 analog) at a dose of 0.015 mg/kg failed to alter open field behaviour of rats in the first test series. The peptide abolished amphetamine-induced stimulation of the exploratory and grooming behaviour. Extinction of the rats' exploratory behaviour during second test series in the open field (7 days later) was disturbed when haloperidol or apomorphine were injected before the first test series. When the peptide was administered with haloperidol or apomorphine, the extinction tended to become normal. Heptapeptide failed to change noradrenaline, dopamine or 5-hydroxytryptamine content in the rat forebrain. However, this peptide at a concentration of 10(-4) M moderately diminished tyrosine hydroxylation velocity in the rat striatal or hypothalamic synaptosomes, the effect depending on tyrosine concentration. These data suggest the involvement of catecholaminergic component into the heptapeptide action on the behaviour of rats. 相似文献
3.
M S Petrova R G Shakirova N A Antonova G N Feoktistova 《Antibiotiki i khimioterapii͡a》1992,37(11):40-43
The data accumulated within the last years required revision of the indications to the use of antibiotics in treatment of pertussis. One of the aims of antibiotic therapy in pertussis was to prevent colonization of B. pertussis in the respiratory tracts. With that end in view the choice of antibiotics should be limited by those, to which the pathogen is the most sensitive i.e. erythromycin, ampicillin and augmentin. Comparative efficacy of erythromycin and ampicillin during the first 2 weeks of the disease was studied in 79 infants at the age not older than 1 year with pertussis and it was shown that erythromycin was advantageous by its therapeutic activity and less side effects. Expedience of the antibiotic therapy during the spastic period for providing a preventive effect on development of bronchopulmonary complications was studied in 201 patients with pertussis. No preventive effect of the antibiotics on development of the bronchopulmonary complications defined by the secondary bacterial flora was recorded. In the group of the patients treated with the antibiotics prophylactically (group 1) the complications were 2.6 times more frequent than in the patients treated with pathogenetic agents alone (group 2). Intrahospital pneumonia developed in 8.9 per cent of the patients in group 1 and in 1.5 per cent of the patients in group 2. Therefore, antibiotics should not be used at the late periods of pertussis for prophylaxis of secondary bacterial complications. 相似文献
4.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals. 相似文献
5.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
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Interstitial cells of the renal papilla have the phenotypic appearance, being more of a fibroblast than of a histiocyte character. Interstitial cells differ from the "typical fibroblasts" in the number of lipid droplets, in the development of cisternae of the Golgi complex and rough endoplasmic reticulum, and in the number of lysosome-like bodies and mitochondria. 相似文献
8.
L B Hejfets L A Levina L V Salmin A A Antonova L S Segal M L Kuzminova K M Slavina A V Vasileva 《Journal of hygiene, epidemiology, microbiology, and immunology》1976,21(3):292-299
A total of 3 controlled field trials were carried out. One of them (1963) showed that aerosol chemical typhoid vaccine did not protect vaccinated subjects from the disease. Two other tests (1964 and 1965) assessing the effectivity of killed orally administered typhoid vaccine revealed a short term (up to 3 months) protective effect expressed by an effectivity coefficient of 45%, fiducial limits being 8-70%. In the assessment of oral paratyphoid B vaccine, the difference in morbidity in the experimental and control groups was statistically insignificant due to a small number of cases of disease. 相似文献
9.
大中型食肉动物肇事事件导致人类与野生动物关系恶化,给生物多样性保护工作带来巨大的挑战。若尔盖湿地是我国三大湿地之一,湿地、草原分布广泛,生物多样性丰富,畜牧业发达,但近年来狼(Canis lupus)捕杀牲畜的肇事事件时有发生。为了解若尔盖野生狼肇事件的空间分布以及牧民对人-狼冲突管理的看法,本研究于2022年对若尔盖县13个乡镇83个行政村进行走访调查。结果表明:(1)多数受访者(66.0%)认为在过去5年内,若尔盖县野生狼数量有所增加;(2)狼肇事事件具有明显的空间分异性,最严重的是包座乡。包座乡临近山区,该区域牧场面积广阔、牧民饲养牲畜数量多等原因导致该镇发生狼肇事事件较多;(3)对于狼肇事,绝大多数牧民(85.0%)更希望采取经济补偿或者驱赶措施,只有少数牧民(9.4%)希望采取捕杀的措施;(4)影响牧民对狼肇事管理措施的偏好因子中,受教育程度、年龄、民族以及被杀牲畜数量有显著影响。建议加强狼种群监测管理,采取措施减少狼捕杀牲畜,优化补偿机制,缓解当地牧民与狼之间的矛盾。本研究为当前若尔盖县野生动物保护和管理决策提供了依据,对其他地区大型食肉动物与当地居民冲突管理具有借鉴意义。 相似文献
10.
肠道病毒71型作为引起儿童群体常见传染性手足口病(HFMD)的主要病原,具有导致少量感染个体出现脑炎等神经系统病变以及相关心肺功能衰竭的病理学特性.因此其预防性疫苗的研发具有重要的公共卫生意义.在前期工作的基础上,一种EV71灭活病毒疫苗(人二倍体细胞)在本研究中基于恒河猴婴猴模型进行了相应的免疫保护性分析.以160EU剂量对2~3月龄婴猴进行0,4周免疫后,动物在第4周接受了剂量为10。~CCID50的病毒经呼吸道的攻击.对病毒攻击后动物在14天内的临床症状、血液生物学、器官病原学分布以及病理学检测的动态观察表明,经疫苗免疫的动物未出现对照动物所具有的特征性临床表现,其血液生物学及病理学检测均无异常.同时,器官病原学分布亦呈阴性.结合动物中和抗体的明确增长及对照动物的综合表现分析,本文的工作证实了该EV71灭活病毒疫苗(人二倍体细胞)在恒河猴婴猴体内的免疫保护性. 相似文献