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Mixed urogenital infection in men   总被引:1,自引:0,他引:1  
High occurrence of sexually transmitted diseases (STD) caused by a combination of different infective agents was established. In 62.5% of cases such diseases took a course typical for mixed infections. Combinations of infective agents of STD were found to have several typical associations, e.g. Ureaplasma urealyticum and Mycoplasma hominis in combination with opportunistic microflora. The microbiocenosis of the reproductive tract was shown to form under the influence of a complex of endogenous (natural biological) and exogenous (sexual behavioral) factors leading, in each particular case, to the formation of stable associations.  相似文献   
33.
Two new steroid glycosides from the starfish Fromia milleporella collected in the Seychelles were isolated and characterized: milleporoside A, (20R, 24R)-29-O-[3-O-methyl-beta-D-xylopyranosyl-(1-->4)-3-O-methyl-beta-D-xylopyranosyl]-24-ethyl-5alpha-cholestane-3beta,4beta,6alpha,8,15beta,16beta,29-heptaol, and milleporoside B, (20R, 24R)-(22E)-28-O-[3-O-methyl-beta-D-xylopyranosyl-(1-->4)-3-O-methyl-beta-D-xylopyranosyl]-24-methyl-5alpha-cholest-22-ene-3beta,4beta,6alpha,8,15beta,16beta,28-heptaol. The structures of the glycosides were determined from their spectra and a comparison with spectral characteristics of known compounds. These compounds exhibit a moderate cytostatic activity toward the embryos of the sea urchin Strongylocentrotus intermedius.  相似文献   
34.
A study of the morphology of the salivary glands of the colubrid snake Oxyrhopus trigeminus showed the following: The acini of supralabial, infralabial, and premaxillary glands are formed by mucous and mucoserous cells; the tubules of Duvernoy's gland are formed by seromucous cells; and mucous cells produce neutral and acid mucosubstances, mucoserous cells secrete neutral and acid mucosubstances and protein, and seromucous cells have neutral mucosubstance and protein secretions.  相似文献   
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Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies.  相似文献   
37.
Microbiological technology for the enhancement of oil recovery based on the activation of the stratal microflora was tested in the high-temperature horizons of the Kongdian bed (60 degrees C) of the Dagang oil field (China). This biotechnology consists in the pumping of a water-air mixture and nitrogen and phosphorus mineral salts into the oil stratum through injection wells in order to stimulate the activity of the stratal microflora which produce oil-releasing metabolites. Monitoring of the physicochemical, microbiological, and production characteristics of the test site has revealed large changes in the ecosystem as a result of the application of biotechnology. The cell numbers of thermophilic hydrocarbon-oxidizing, fermentative, sulfate-reducing, and methanogenic microorganisms increased 10-10 000-fold. The rates of methanogenesis and sulfate reduction increased in the near-bottom zone of the injection wells and of some production wells. The microbial oil transformation was accompanied by the accumulation of bicarbonate ions, volatile fatty acids, and biosurfactants in the formation waters, as well as of CH4 and CO2 both in the gas phase and in the oil. Microbial metabolites promoted the additional recovery of oil. As a result of the application of biotechnology, the water content in the production liquid from the test site decreased, and the oil content increased. This allowed the recovery of more than 14000 tons of additional oil over 3.5 years.  相似文献   
38.
Higher harmonics of alternating current in bilayer lipid membranes caused by sinusoidal voltage applied to the membrane were measured. The bilayer lipid membranes were prepared from diphytanoylphosphatidylcholine in n-decane and n-tetradecane, and measurements were conducted with the aid of an analog-to-digital converter of 16th category. Sinusoidal voltage was formed using a digital-to-analog converter of the 16th category. The dynamic region of measurements was up 90 dB. The results of measurements were used to determine the alpha and beta coefficients of the expansion of membrane capacity C in terms of membrane voltage U C = C0 (1 + alphaU2 + betaU4). We showed in the framework of the electrostriction model that the relation between the alpha and beta coefficients characterizes the inhomogeneity of bilayer lipid membrane with respect to its thickness and Young modulus of elasticity.  相似文献   
39.
Recent studies demonstrated that the Golgi reassembly stacking proteins (GRASPs), especially GRASP55, regulate Golgi-independent unconventional secretion of certain cytosolic and transmembrane cargoes; however, the underlying mechanism remains unknown. Here, we surveyed several neurodegenerative disease–related proteins, including mutant huntingtin (Htt-Q74), superoxide dismutase 1 (SOD1), tau, and TAR DNA–binding protein 43 (TDP-43), for unconventional secretion; our results show that Htt-Q74 is most robustly secreted in a GRASP55-dependent manner. Using Htt-Q74 as a model system, we demonstrate that unconventional secretion of Htt is GRASP55 and autophagy dependent and is enhanced under stress conditions such as starvation and endoplasmic reticulum stress. Mechanistically, we show that GRASP55 facilitates Htt secretion by tethering autophagosomes to lysosomes to promote autophagosome maturation and subsequent lysosome secretion and by stabilizing p23/TMED10, a channel for translocation of cytoplasmic proteins into the lumen of the endoplasmic reticulum–Golgi intermediate compartment. Moreover, we found that GRASP55 levels are upregulated by various stresses to facilitate unconventional secretion, whereas inhibition of Htt-Q74 secretion by GRASP55 KO enhances Htt aggregation and toxicity. Finally, comprehensive secretomic analysis identified novel cytosolic cargoes secreted by the same unconventional pathway, including transgelin (TAGLN), multifunctional protein ADE2 (PAICS), and peroxiredoxin-1 (PRDX1). In conclusion, this study defines the pathway of GRASP55-mediated unconventional protein secretion and provides important insights into the progression of Huntington’s disease.  相似文献   
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