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1.
The short-term prognosis of the epidemic situation requires the establishment of the system of constant surveillance, which takes into account the data on morbidity rates for several years, both total and in various age groups, the data on the morbidity level and its changes, induced by meningococci of the epidemic group, in the IV quarter of the year, the data on the level of carriership among the indicator groups of the population in this period, as well as the data on changes in antibody titers in the sera of donor blood samples taken in summer and in December.  相似文献   
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The activity of the third International Standard of streptomycin was determined to be equal to 755 IU/mg with the use of accurately weighed amounts of streptomycin and 78037 IU with the use of streptomycin ampoules. The Standardization Center of the WHO decided to use the whole content of the ampoule of the Third International Standard of streptomycin, the activity of which is determined to be equal to 78500 IU per an ampoule.  相似文献   
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The authors state their opinion on this problem by analyzing their 5-year use of their programme specially developed for detection of breast disease, mainly cancer, among females visiting specialized rooms of non-mammological profiles (gastroenterology, endocrinology, rheumatology, pulmonology, neurology, cardiology, hematology, nephrology, etc.) in the consulting polyclinics of regional (territorial) hospitals and large city hospital-polyclinic complexes. In this period, mammographic studies were made in 9169 women included into a breast cancer-risk group. Of them 1370 young female patients with well-developed glandular tissue that makes mammographic diagnosis of presumed masses difficult underwent breast ultrasonography. Abnormalities were found in 6092 (66.44%) patients. Breast cancer and nodal benign masses (including cysts and fibroadenomas) were detected in 278 (3.03%) and 669 (7.30%) women, respectively. The detection rates of unpalpable breast malignant and benign masses carcinomas were 0.4 and 3.03%, respectively. The findings allow the authors to recommend their proposed screening programme for wide use in large regional (territoreal), city, and town polyclinic complexes.  相似文献   
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Induction of the expression of the delta-endotoxin gene from Bacillus thuringiensis var. tenebrionis in the recombinant strain Pseudomonas putida IPM-36 negatively affected the viability and the growth rate of the culture. In order to optimize the insecticide production by the recombinant strain, mutant clones exhibiting anticipating growth on an inducer-containing medium were selected and studied. These clones differed in such aspects as the localization of mutations (either in plasmid pBTN11, carrying the cry3A gene, or in the chromosome), growth rate, or the level of delta-endotoxin synthesis after induction. Several mutants obtained proved much superior to P. putida IPM-36 in their structural and segregation stability, although they were as efficient as the original strain with respect to the production of the insecticide (protei Cry3A).  相似文献   
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Combination of two factors in rats such as the isolation (during 2-4 months, beginning from the 21st day of age) and procedure of space cyclic learning results in a rare kind of behavioral strategy (in 30% animals), when the cyclic behavior is realized without food reinforcement. Such a dissociation between the vital motivation and searching behavior may be considered as an analogue of the disintegration phenomenon in neuropsychotic patients. The deep depression of learning owing to lowering of search represents the dominant type of behavioral disorders in isolants. The cyclic habit training, including a 2-months pause between two sessions, significantly increases behavioral search activity. The behaviors are accompanied by morphological shifts in the sensomotor cortex: significant decrease of the fifth layer (giant pyramids) thickness, selective lowering in the satellite glia density and elimination of normal behavior-glia correlations.  相似文献   
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A study was made of changes in the rates of respiration, heat production, and membrane characteristics in cells of excised roots of wheat seedlings under the modulation of plasma membrane ion permeability by two membrane active compounds: valinomycin (20 microM (V50)) and chlorpromazine (50 microM (CP50) and 100 microM (CP100)). Both compounds increased the loss of potassium ions, which correlated with the lowering of membrane potential, rate of respiration, and heat production after a 2 h exposure. The differences in alteration of these parameters were due to specific action of either compound on the membrane and to the extent of ion homeostasis disturbance. V20 had a weak effect on the studied parameters. V50 caused an increase of the rate of respiration and heat production, which enhanced following a prolonged action (5 h) and were associated with ion homeostatis restoration. The extent of alteration of membrane characteristics (an increase of potassium loss by roots, and lowering of cell membrane potential) as well as energy expense under the action of CP50 during the first period were more pronounced than in the presence of V50. During a prolonged action of CP50, the increase of respiration intensity and heat production correlated with partial recovery of ion homeostatis in cells. Essential lowering of membrane potential and substantial loss of potassium by cells, starting from the early stages of their response reaction, were followed by inhibition of respiration rate and heat production. Alterations of the structure and functional characteristics of excised root cells indicate the intensification of the membrane-tropic effect of a prolonged action of CP100, and the lack of cell energy resources.  相似文献   
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Melanoma is the most lethal cutaneous cancer with a highly aggressive and metastatic phenotype. While recent genetic and epigenetic studies have shed new insights into the mechanism of melanoma development, the involvement of regulatory non‐coding RNAs remain unclear. Long non‐coding RNAs (lncRNAs) are a group of endogenous non‐protein‐coding RNAs with the capacity to regulate gene expression at multiple levels. Recent evidences have shown that lncRNAs can regulate many cellular processes, such as cell proliferation, differentiation, migration and invasion. In the melanoma, deregulation of a number of lncRNAs, such as HOTAIR, MALAT1, BANCR, ANRIL, SPRY‐IT1 and SAMMSON, have been reported. Our review summarizes the functional role of lncRNAs in melanoma and their potential clinical application for diagnosis, prognostication and treatment.  相似文献   
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