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971.
S. M. Gueye S. N. Diop P. A. Fall E. K. Dagadou M. O. C. Abdallahi M. Ba A. Mensah 《Andrologie》1999,9(4):515-518
Objective
To assess the etiological factors of erectile dysfunction in male diabetics.Material and methods
We have performed a prospective evaluation including 69 diabetic patients suffering from erectile dysfunction. Studied parameters including age, type and duration of diabetes, complications, treatments and associated risk factors were analysed. Comparison was done with a control group of 138 diabetic patients without erectile dysfunction.Results
There was a significant difference between the diabetic with neurologic complications and the others without neuropathy (p=0.0004). The duration of the diabete was was another risk factor of erectile dysfunction (p=0.049)Conclusion
We confirm various authors who demonstrated that diabetic impotence seems to be mainly neuropathic in etiology even though it was a multifactorial discomfort. 相似文献972.
Korshunov VM Urtaeva ZA Smeianov VV Efimov BA Sarkisov SE Krymshokalova ZA Baĭnov NA Pikina AP Korshunova OV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1999,(5):72-77
The antagonistic activity of 4 strains of bifidobacteria (B. adolescentis 2 F1, B. longum Z4, B. breve R2 and B. bifidum G1), isolated from the vagina of healthy females of the reproductive age, with respect to Escherichia coli, Klebsiella ozaenae, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Gardnerella vaginalis were studied in vitro and in vivo. The in vitro experiments revealed that all above-mentioned bifidobacteria were capable of inhibiting the growth of all indicator bacterial strains. Still of all the bifidobacteria under study had different levels of activity. B. adolescentis strain 2 F1 exhibited the highest inhibiting activity in vitro. In contrast to in vitro experiments, in vivo experiments with B. breve R2 demonstrated its high antagonistic activity with respect to E. coli. The data thus obtained indicate that in the study of antagonistic activity the use of the in vivo model as also expedient, for it is mainly in vivo that probiotic preparations show their activity. 相似文献
973.
By the methods of NMR, PMR and EPR spectrometry and X-ray diffaction, the occurrence of polymorphic liquid-crystalline transformations in phosphatidylcholine liposomes from the bovine brain and the influence of phenozan (sterically screened phenol antioxidant) and adrenocorticotropic hormone were shown in the temperature range 25-55 degrees C. Phenozan and the adrenocortcotropic hormone, which have a nootropic activity in vivo, change the phase transition temperatures, promote polymorphic transformations in lipids and increase the disordering of lipid bilayer and the thickness of phosphatidylcholine membranes. We assume that the lipid polymorphysm is a step of information recording and keeping processes in synapse membranes. 相似文献
974.
Supply P Warren RM Bañuls AL Lesjean S Van Der Spuy GD Lewis LA Tibayrenc M Van Helden PD Locht C 《Molecular microbiology》2003,47(2):529-538
Deciphering the structure of pathogen populations is instrumental for the understanding of the epidemiology and history of infectious diseases and for their control. Although Mycobacterium tuberculosis is the most widespread infectious agent in humans, its actual population structure has remained hypothetical until now because: (i) its structural genes are poorly polymorphic; (ii) adequate samples and appropriate statistics for population genetic analysis have not been considered. To investigate this structure, we analysed the statistical associations (linkage disequilibrium) between 12 independent M. tuberculosis minisatellite-like loci by high-throughput genotyping within a model population of 209 isolates representative of the genetic diversity in an area with a very high incidence of tuberculosis. These loci contain variable number tandem repeats (VNTRs) of genetic elements named mycobacterial interspersed repetitive units (MIRUs). Highly significant linkage disequilibrium was detected among the MIRU-VNTR loci in this model. This linkage disequilibrium was also evident when the MIRU-VNTR types were compared with the IS6110 restriction fragment length polymorphism types. These results support a predominant clonal evolution of M. tuberculosis. 相似文献
975.
Vakhitov VA Chemeris AV Sabirzhanov BE Akhunov ED Kulikov AM Nikonorov IuM Gimalov FR Bikbulatova SM Baĭmiev AKh 《Genetika》2003,39(1):5-17
The process of accumulation of knowledge on wheat and related wild species during the 20th century is briefly reviewed with special reference to the evidence of the recent years on evolution of polyploid wheats and the role of diploid species. The latter serve as potential donors of the genomes, detection of which is particularly important because of the continuing speciation in the tribe Triticeae and artificial development of synthetic forms. The arguments in favor of the donor role for various diploid wheat species and aegilopses from the section Sitopsis are compared. It is stated that in the formation of the both lines of polyploid wheats turgidum-aestivum and timopheevi, diploid Aegilops speltoides acted as a maternal form. In addition to plasmatic genomes, this aegilops species introduced into them also the B and G nuclear subgenomes. A comparison of nucleotide sequences in the variable part of the promoter of evolutionary conserved rRNA genes in polyploid wheats with their counterparts in diploid wheats and aegilopses confirmed the accepted wheat phylogenies. 相似文献
976.
977.
Inventory and functional characterization of the HAK potassium transporters of rice 总被引:29,自引:0,他引:29
Plants take up large amounts of K(+) from the soil solution and distribute it to the cells of all organs, where it fulfills important physiological functions. Transport of K(+) from the soil solution to its final destination is mediated by channels and transporters. To better understand K(+) movements in plants, we intended to characterize the function of the large KT-HAK-KUP family of transporters in rice (Oryza sativa cv Nipponbare). By searching in databases and cDNA cloning, we have identified 17 genes (OsHAK1-17) encoding transporters of this family and obtained evidence of the existence of other two genes. Phylogenetic analysis of the encoded transporters reveals a great diversity among them, and three distant transporters, OsHAK1, OsHAK7, and OsHAK10, were expressed in yeast (Saccharomyces cerevisiae) and bacterial mutants to determine their functions. The three transporters mediate K(+) influxes or effluxes, depending on the conditions of the experiment. A comparative kinetic analysis of HAK-mediated K(+) influx in yeast and in roots of K(+)-starved rice seedlings demonstrated the involvement of HAK transporters in root K(+) uptake. We discuss that all HAK transporters may mediate K(+) transport, but probably not only in the plasma membrane. Transient expression of the OsHAK10-green fluorescent protein fusion protein in living onion epidermal cells targeted this protein to the tonoplast. 相似文献
978.
Pashkov VS Mareeva TIu Balashova TA Vychalkovskiĭ AA Samokhvalova LV Baĭdakova LK Rodionov IL Nesmeianov VA 《Bioorganicheskaia khimiia》2002,28(2):109-117
Effect of the monoclonal antibody (MAb) 5B6 produced to the solubilized preparation of bacteriorhodopsin on the protein photocycle was studied to examine conformational rearrangements on the surface of functioning bacteriorhodopsin molecule. Using the methods of solid phase enzyme immunoassay, peptide phage display, and 1H NMR spectroscopy, we demonstrated that the epitope recognized by MAb 5B6 is the Val69-Pro-Phe-Gly72 fragment of the protein, with the aromatic ring of Phe71 and the methyl groups of Val69 participating in the binding. MAb 5B6 exerted no significant effect on the photocycle of bacteriorhodopsin solubilized in Triton X-100 at pH 6.2 and 7.4, which suggested that, when functioning, bacteriorhodopsin retains the conformation and position of its Val69-Pro-Phe-Gly72 fragment. 相似文献
979.
- 1 To contribute to the development of IPM strategies in olive groves, the selectivity of several insecticides to Pullus mediterraneus Fabr. (Coleoptera: coccinellidae) was investigated in the laboratory. The study assessed the toxicity of seven chemical pesticides and one bacteriological insecticide to adult P. mediterraneus.
- 2 The LC50 was estimated by applying the pesticides on the dorsal side of adults. Lambda‐cyhalothrin, methomyl and cypermethrin resulted in the highest toxicity followed, in decreasing order of toxicity, by malathion, fenthion and dimethoate. Parathion had the least effect on the coccinellid.
- 3 Consumption of Bacillus thuringiensis bacteria (applied as a commercial formulation), over a period of 10 consecutive days, resulted in low mortality of adult P. mediterraneus.
- 4 The results of these laboratory experiments indicate that the most widely used chemical pesticides were toxic to P. mediterraneus. Their use in olive groves must take account of the activity period of this predator. In contrast, B. thuringiensis seemed to be a suitable candidate to be included in pest management systems.
980.