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31.
Variability of the haptoral hard parts of four Black Sea Gyrodactylus species (G. alviga Dmitrieva & Gerasev, 2000; G. crenilabri Zaika, 1966; G. flesi Malmberg, 1957; G. sphinx Dmitrieva & Gerasev, 2000) was studied in relation to season, host and geographical variability. A discriminant analysis was carried out on the measurements of 14 characters of the haptor of all four species. The haptoral hard parts of the investigated gyrodactylids decrease in size with an increase in water temperature. It is known that life-span of gyrodactylids is negatively correlated with water temperature and they exhibit peak intensities at low temperature. At the same time, life-span is considered to be a general indicator of a favourable environment. Therefore, high water temperature is not apparently advantageous for gyrodactylids. In the case of low marine salinity, in adapted species the sizes of the haptoral hard parts are larger at lower levels of salinity and vice versa for typical marine species. Lastly, in specimens parasitising the primary host, these features are larger than in those parasitising a secondary host. It is possible to say that, in general, the more favourable the environment for gyrodactylids the larger their haptoral hard parts. Unfavourable environmental conditions reduce the time of embryogenesis, which has a dual effect on gyrodactylids: positive in relation to their reproduction (by increasing the reproduction rate) and negative in relation to their development (by decreasing the size of the haptoral hard parts). 相似文献
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Glycolate oxidase isoforms are distributed between the bundle sheath and mesophyll tissues of maize leaves 总被引:5,自引:0,他引:5
Glycolate oxidase (EC 1.1.3.15) activity was detected both in the bundle sheath (79%) and mesophyll (21%) tissues of maize leaves. Three peaks of glycolate oxidase activity were separated from maize leaves by the linear KCl gradient elution from the DEAE-Toyopearl column. The first peak corresponded to the glycolate oxidase isoenzyme located in the bundle sheath cells, the second peak had a dual location and the third peak was related to the mesophyll fraction. The mesophyll isoenzyme showed higher affinity for glycolate (Km 23 micromol x L(-1)) and a higher pH optimum (7.5-7.6) as compared to the bundle sheath isoenzyme (Km 65 micromol x L(-1), pH optimum 7.3). The bundle sheath isoenzyme was strongly activated by isocitrate and by succinate while the mesophyll isoenzyme was activated by isocitrate only slightly and was inhibited by succinate. It is concluded that although the glycolate oxidase activity is mainly attributed to the bundle sheath, conversion of glycolate to glyoxylate occurs also in the mesophyll tissue of C4 plant leaves. 相似文献
34.
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
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Dmitrieva LI Stepanian IE Perfil'ev AV Shemetun ON Romanov RG 《Vestnik rentgenologii i radiologii》2000,(3):8-16
The authors studied the pattern of X-ray changes detectable in the lungs of 41 patients with LCH. The results of classical X-ray study were supplemented by the data of computed tomography, ultrasonography, and 99mTc and 67Ga citrate radioisotopic studies. The diagnostic values of these techniques were compared. X-ray syndromes of changes in the lung in LCH were found to be interstitial, interstitial and granulomatous, tumorous (focal). The authors emphasize the multisystematic character of a lesion, the phasic nature and progression of the disease into fibrosis. 相似文献
37.
Dmitrieva NA Molchan OK Komissarov AA Sokolov VB Aksinenko AIu Pushin AN Chekhlov AN Debabov VG 《Bioorganicheskaia khimiia》1998,24(12):920-925
5,5-Bis(hydroxymethyl)-2-oxo-[1-(2-trifluoromethyl)-3,3,3- trifluoropropionamido)-1-trifluoromethyl-2,2,2-trifluoroethyl- 1,3,2-dioxaphosphan (CA-423) is an in vitro inhibitor of the Escherichia coli uridine and thymidine phosphorylases. Unlike widely studied nucleoside analogues, this compound binds to the enzymes irreversibly. Its LD50 in mice was 40 mg/kg. Due to the involvement of pyrimidine phosphorylases in carcinogenesis and the relatively low toxicity of CA-423, it is promising for anticancer therapy. 相似文献
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S V Minenko N V Dmitrieva K L Chimishkian N V Zhukov E N Sokolova V B Larionova V V Ptushkin 《Antibiotiki i khimioterapii͡a》2002,47(7):13-19
Evaluation of benzylpenicillin (penicillin G) effect for infection prophylaxis at the oncological patients with severe postcytostatic neutropenia was performed. All the patients with neutrophils levels lower than 0.5 x 10(9)/L were recommended to use antibiotics for infection prophylaxis. Test-group (n = 40) used ciprofloxacin (0.5 g twice daily, per os) combined with benzylpenicillin (1.0 g four times daily, i/v); control group was treated by ciprofloxacin in the same dose only. Combination with benzylpenicillin resulted in statistically significant reduction of infections frequency among oncological patients. 相似文献
40.
Rachaneeporn Tiyawisutsri Matthew TG Holden Sarinna Tumapa Sirirat Rengpipat Simon R Clarke Simon J Foster William C Nierman Nicholas PJ Day Sharon J Peacock 《BMC microbiology》2007,7(1):19