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1.
Restriction maps of the rDNA cistron of twelve species of mosquitoes in six genera of the subfamily Culicinae were constructed using eight 6 bp recognition restriction enzymes. Anopheles albimanus was used as an outgroup. The size of the rDNA cistron ranged from 8.5 kb in Aedes katherinensis to 12.9 kb in Ae. polynesiensis. A total of twenty-six sites were scored; eighteen were polymorphic among ingroup taxa. The proportion of polymorphic nucleotide sites (Pnuc) was 0.059 and the heterozygosity per nucleotide site (Hnuc) was 0.028. Wagner and Fitch Parsimony, Dollo Parsimony and Nei-Li distance/neighbour-joining methods were used to construct phylogenetic trees. The rDNA RFLP dataset did not provide a well-supported phylogeny among culicine taxa. The RFLP phylogenies are incongruent with the morphology character based and molecular phylogenies and derived relationships did not correspond with current taxonomic classifications. The lack of resolution was due to homoplasy arising from frequent independent loss or gain of restriction sites among unrelated taxa.  相似文献   
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The results of a study of a new synthetic drug dimephosphon used as a pathogenetic means in the treatment of experimental tuberculosis are presented. Dimephosphon was found to be responsible for both the in vivo and in vitro decrease of the degree of MBT resistance to rifampicin. The findings of macroscopic, histologic and bacteriologic examinations demonstrated a significant increase in the effectiveness of antituberculous therapy. Dimephosphon monotherapy in mice elicited manifested stimulation of peritoneal macrophages: increase in O2- production, and decline in extracellular 5-nucleotidase activity. Nemolysine-synthetic cellular splenic activity in mice rose essentially. No direct stimulating influence of dimephosphon on functional macrophage activity in vitro was found.  相似文献   
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The effects of herpes vaccine on immunologic parameters and clinical manifestations of recurrent herpes stomatitis (RHS) were studied. Altogether 70 patients with RHS were examined: 30 before and 40 after vaccination and revaccination. The clinical effect of vaccination was shown to be associated with stimulation of cell-mediated factors of immunity as well as with the desensitizing effect of the vaccine. It is suggested that herpes vaccine is characterized by immunomodulating properties.  相似文献   
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Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 25, No. 6, pp. 57–59, June, 1991.  相似文献   
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Examination of 38 patients with chronic postembolic pulmonary hypertension revealed gross hemorheological disorders: increased viscosity of blood, extreme aggregation activity of blood cells, diminished property or erythrocytes to undergo deformity when circulating through the capillaries. Small amounts of UV-irradiated autologous blood were infused repeatedly for the correction of these disorders. After a course of treatment the hemorheological indices were normalized in all the patients, which was attended by improvement of the general condition and positive hemodynamic shifts.  相似文献   
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We studied the effect of culturing conditions on the fate of human neural stem cells after transplantation into rat brain. Human neural stem cells cultured in the presence of mitogens without LIF migrated along the ependyma and cerebral vessels of recipients, but to a great extent degenerated by the 20th day after transplantation. Neural stem cells cultured with LIF migrated, apart from the above mentioned pathways, in the cortex and hippocampus, well survived; proliferating cells were retained 30 days after transplantation.__________This revised version was published online in July 2005 with the addition of the issue title and article categoryTranslated from Kletochnye Tekhnologii v Biologii i Meditsine, Vol. 1, No. 1, pp. 13–19, January, 2005  相似文献   
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Dihydropyridine (DHP) calcium channel antagonists, which inhibit the slowly inactivating or L-type cardiac calcium (Ca) current, have been shown to be ineffective in blocking45Ca influx and Ca-dependent secretion in a number of neuronal preparations. In the studies reported here, however, the antagonist DHP nifedipine inhibited both the L-type Ca current and potassium-evoked substance P (SP) release from embryonic chick dorsal root ganglion (DRG) neurons. These results suggest that, in DRG neurons. Ca entry through L-type channels is critical to the control of secretion. The inhibition of Ca current by nifedipine was both voltage and time-dependent, significant effects being observed only on currents evoked from relatively positive holding potentials maintained for several seconds. As expected from these results, nifedipine failed to inhibit L-type Ca current underlying the brief plateau phase of the action potential generated from the cell's normal resting potential; likewise, no significant effect of the drug was observed on action potential-stimulated SP release evoked by electrical field stimulation. The results of this work are discussed in terms of an assessment of the role of L-type Ca channels in neurosecretion.This work was supported by United States Public Health Service Grant NS16483 (KD) and by a USPHS Postdoctoral Fellowship (SGR)  相似文献   
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