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91.
The tick Ixodes persulcatus Schulze, 1930, has a wide distribution from the Baltic to the Far East and is a vector of a number of human pathogens. Thus, the study of the genetic structure and evolution of this species is of great epidemiological importance. rRNA genes were used as genetic markers to identify the phylogeographical structure of the ticks. The sequences of gene fragments of 28S (expansion segment D3) and mitochondrial 12S rRNA for 25 and 76 ticks, respectively, that had been collected in various regions of Russia in 2007–2011, were obtained. The sequences of the 28S rRNA D3 segment were identical for all ticks within the studied area. Analysis of the sequences of the mitochondrial 12S rRNA fragment revealed 4 haplotypes with one occurring at a frequency of 0.96. It is shown that the ‘deep’ population structure of I. persulcatus (McLain et al., 2001) was erroneous because of the inclusion of contaminating fungi sequences of 28S rRNA in the phylogenetic analysis. This was, possibly, due to the use of universal PCR primers that amplify the DNA of a wide range of eukaryotes, particularly of fungi which are common in samples of ticks. The influence of PCR conditions on the preferential amplification of the DNA of different organisms is also demonstrated. 相似文献
92.
During four weeks rats were learned to visit consequently 4 baited arms in the 8-armed radial maze. Picamilone (nicotinoyl-GABA) in a dose of 10 mg/kg daily accelerated rats to reach 80% level of learning (to 20-28 trials). After picamilone injections rats obtained the maximal level of short-term memory as just 3-5 trials. Piracetam in a dose of 200 mg/kg daily exerted no effects on long-term and short-term memory of rats in the radial maze. 相似文献
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The effect of a central fusion lock on forced vergence fixation disparity curve parameters, that is, magnitudes of fixation disparity and associated phoria, curve type and the central slope of the curve, was studied in 84 subjects because of ambiguity in the previous studies. It was found that the magnitudes of exo fixation disparity and exo associated phoria decreased significantly when they were measured with the central fusion lock. The central lock had no noticeable effect on the type of the curve, although, the central slope of the curve was flatter in the presence of the central lock. 相似文献
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Transient synovitis of the hip in children: role of US 总被引:7,自引:0,他引:7
Marchal GJ; Van Holsbeeck MT; Raes M; Favril AA; Verbeken EE; Casteels- Vandaele M; Baert AL; Lauweryns JM 《Radiology》1987,162(3):825-828
Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies. 相似文献
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A. A. Spasov G. V. Kovalev A. V. Tsibanev 《Bulletin of experimental biology and medicine》1990,110(2):1062-1065
Department of Pharmacology, Volgograd Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR D. A. Kharkevich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 8, pp. 164–166, August, 1990. 相似文献