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121.
The analysis of changes in the epidemic situation with HIV infection in Kaliningrad Province, the first territory in Russia involved into the epidemic, is presented. The experience in the realization of preventive programs is discussed with the analysis of both successes and problems arising in Kaliningrad, whose inhabitants constitute the absolute majority among HIV-infected persons in the region. The expediency of creating a new section--service of information, consultation and psychological assistance in the AIDS Centers is proposed for discussion.  相似文献   
122.
Forty serotonin-related neurochemicals were tested on embryos and larvae of Lytechinus variegatus and other sea urchin species. Some of these substances (agonists of 5-HT1 receptors, antagonists of 5-HT2, 5-HT3 or 5-HT4 receptors, and inhibitors of the serotonin transporter, SERT) perturbed post-blastulation development, eliciting changes in embryonic/larval phenotypes typical for each class of receptor ligand. These developmental malformations were prevented completely or partially by serotonin (5-HT) or 5-HT analogs (5-HTQ, AA-5-HT), providing evidence for the putative localization of cellular targets. Immunoreactive 5-HT, 5-HT receptors and SERT were found in pre-nervous embryos and larvae of both L. variegatus and Strongylocentrotus droebachiensis. During gastrulation, these components of the serotonergic system were localized to the archenteron (primary gut), mesenchyme-like cells, and often the apical ectoderm. These results provide evidence that pre-nervous 5-HT may regulate early events of sea urchin embryogenesis, mediated by 5-HT receptors or the 5-HT transporter.  相似文献   
123.
A collection of DNA samples obtained from primary open-angle glaucoma (POAG) patients from St. Petersburg was analyzed for single-strand conformation polymorphism (SSCP) to reveal sequence variants in exon 3 of the myocilin gene (MYOC/TIGR) and in exons 4 and 5 of the optineurin gene (OPTN), where most of the mutations revealed worldwide are located. The Q368X mutation (c. 1102 C → T) in exon 3 of MYOC/TIGR was detected in 1.2% (2/170) of the POAG patients from St. Petersburg, i.e., with the frequency close to that observed in other world populations. Three known polymorphisms in exon 3 of MYOC/TIGR were detected in glaucoma patients, namely Y347Y (c. 1041 T → C) (12.4%), T325T (c. 975 G → A) (0.6%), and K398R (c. 1193 A → G) (0.6%). No statistically significant differences in frequencies of these polymorphisms were revealed between the POAG patient and control groups. The L41L polymorphism (c. 433 G → A) in exon 4 of OPTN was detected in 2.9% of probands and in 1% of controls. The frequency of heterozygotes for the M98K polymorphism (c. 603 T → A) in the OPTN exon 5 was statistically significantly higher (P = 0.036; Fisher's exact test) among the POAG patients (6.5%) than among the controls (1%). In the sample examined the E50K (c. 458G → A) mutation, typical of the patients with pseudonormal intraocular pressure glaucoma (commonly known as low-tension glaucoma, LTG) was not found.  相似文献   
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Choline and N,N-dimethylaminoethyl esters of arachidonic and some other fatty acids were synthesized. Experiments on the embryos and larvae of sea urchins, sensitive to cholinergic compounds, showed that arachidonoylcholine exhibited cholinomimetic activity similar to that of nicotine while N,N-dimethylaminoethyl arachidonate acted as acetylcholine antagonist. The corresponding esters of docosahexaenoic acid were found to manifest similar biological properties.  相似文献   
126.
It has been found for the first time that protein deficit in female's nutrition during prenatal development of the offspring is accompanied by considerable changes in the activity of intestinal digestive enzymes and of the same hydrolases in the colon, liver and kidneys both in early and in late ontogenesis. It seems possible that changes of the small intestine enzyme functions and hydrolytic functions of other digestive and non-digestive organs in result of an unfavorable early "metabolic/nutritional programming" may be crucial in disorders of metabolic processes leading to development of diseases of risk in adult life.  相似文献   
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Lipid peroxidation was studied in the course of the development of anoxic injury to the mitochondria in vitro. Hydrolysis of mitochondial phospholipids was accompanied by an increase in antioxidant activity (AOA) of the organelles. At the same time the ability to transoxidation in liposomes formed from lipids extracted from the injured mitochondria was discovered to be increased. It is assumed that AOA of the mitochondria rises at the expense of antioxidants not extractable with a mixture of chloroform and methanol.  相似文献   
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