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91.
Nefedova VV Korenberg EI Nesterenko LN Gintsburg AL Kovalevskiĭ IuV Gorelova NB 《Parazitologiia》2001,35(1):3-8
Indication of Borrelia (B. burgdorferi sensu lato) in 205 adult unfed I. persulcatus ticks from a natural focus was carried out simultaneously by methods of PCR and dark-field microscopy of vital preparations. PCR method revealed Borrelia prevalence in considerable number of ticks, in which Borrelia were not found by microscopy of 250 microscopic fields in a preparation from each individual tick. At the same time, PCR method didn't give positive results for approximately 8% of ticks, which contained rather high concentration of Borrelia (more than 10 per 100 microscopic fields). In general, PCR method doesn't have advantages in comparison with a microscopy of vital preparations for study the Borrelia prevalence in ticks. 相似文献
92.
The body-wall musculature of invasive cercariae and metacercariae of Diplostomum chromatophorum at different intervals after the penetration into the experimental intermediate host Cyprinus carpio (1, 3, 5, 6, 7, 10, 12, 20, 34, 40 days) has been investigated with the help of TEM technique. During the first 10 days after the invasion (in conditions of our experiment), the cercarial subtegumental muscle fibres degenerate. These muscles are replaced by newly formed ones. Mass differentiation of myoblasts beneath the tegument was observed in 7-10-day-old metacercariae. Obtained data indicate the metamorphosis of body-wall musculature during the morphogenesis in Diplostomum chromatophorum metacercariae. 相似文献
93.
Aniukhovskiĭ EP Rozenshtraukh LV 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1999,85(7):918-930
The ACh shortened the AP in canine epicardial and endocardial cells, the effect being more obvious in the latter. The findings suggest that 4-aminophyridine-sensitive transient outward current is expressed in canine atrial epicardial and endocardial cells, that the ACh exerts direct effects on epicardial and endocardial AP duration, that differential responses of epicardial and endocardial AP duration to the ACh may alter the gradient of repolarisation across the atrial wall and contribute to the vagus-indoced atrial flutter and fibrillation. 相似文献
94.
Kuz'min AI Kalenikova EI Zaretskaia MV Zaretskiĭ DV Zakharova NV Medvedev OS Chazov EI 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1999,85(7):867-877
Physostigmine and an 1-hour immobilisation stress similarly affected functions of the sympatho-adrenal and cardiovascular systems activating the catecholamine secretion and increasing the blood pressure. Yohimbine potentiated the secretory effect but did not change the pressor effect. Intermediate administration of atropine completely eliminated both effects of physostigmine but, being administered prior to the immobilisation, it potentiated the secretory response without affecting the pressor response. The findings reveal a difference in central cholinergic mechanisms of neurohumoral and haemodynamic responses to physostigmine and stress. 相似文献
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