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101.
The variability of the contents of tropane and isoquinoline alkaloids, ashes, Na, K, Ca, Mg, Fe, Mn, Cu, Zn, Co, Mo, Cr, Al, Ba, V, Ni, Sr, Cd, Pb, J, and Ag was studied in individual plants of the industrial population of belladonna (Atropa belladonna L.) and yellow horned poppy (Glaucium flavum Crantz.). Numerous linear and nonlinear correlations of isoquinoline and tropane alkaloids with ashes and mineral elements were revealed by means of correlation and regression analyses. Alkaline earth elements (especially Sr and Ba) were shown to have a major role in the regulation of tropane alkaloid accumulation in belladonna leaves. K and Ni were of particular importance in the aerial part of yellow horned poppy. These elements at the suboptimal concentrations were most favorable for isoquinoline alkaloid accumulation in yellow horned poppy. Analytical mathematical models were derived for the regulation of alkaloid metabolism in test plants by some mineral elements (Ba, Mg, Al, Sr, Ni, Mn, and K). Our results indicate that the interrelation between alkaloids and elements in these plants is genetically determined.  相似文献   
102.
Seven polymorphic microsatellite loci are described in the marine intertidal gastropod Littorina saxatilis. Preliminary data on allelic variation of these loci in a White Sea population of L. saxatilis are presented in order to assess their potential utility as high‐resolution genetic markers for this model species.  相似文献   
103.
The study of the accumulation pattern of extracellular proteins with chitinase activity in the parent Serratia marcescens strain Bú 211 (ATCC 9986) grown in the presence of mitomycin C and its mutant strain with the constitutive synthesis of chitinases grown in the absence of the inducer showed that chitinase activity appeared in the culture liquids of both strains at the end of the exponential phase (4 h of growth) and reached a maximum in the stationary phase (18–20 h of growth). The analysis of the culture liquids (12 h of growth) by denaturing electrophoresis in PAAG followed by the protein renaturation step revealed the presence of four extracellular proteins with chitinase activity and molecular masses of 21, 38, 52, and 58 kDa.  相似文献   
104.
This investigation examined the exposure of Egyptian infants to Aflatoxin M1 (AfM1) and of lactating mothers to Aflatoxin B1, using AfM1 in human milk as a biomarker for exposure to AfB1. The presence of ochratoxin A (OA) in human milk was also investigated to determine the levels of infants exposure to OA from human milk. The results indicated that AfM1 was found in 66 (55 %) of 120 human milk samples with a mean of 0.3 ± 0.53 ng/mL (range 0.02 to 2.09 ng/mL). OA was found in 43 (35.8 %) of 120 human milk samples with a mean of 21.1 ± 13.7 ng/mL (range 5.07 to 45.01 ng/mL), which will cause a daily intake of OA from human milk exceeding the suggested tolerable dose of 5 ng/kg-1 of OA body weight. On the other side AfM1 was found in 25 % of blood samples (5 out of 20 samples), at a mean of 1.18 ng/mL, but it was detected only in one urine sample (1 out of 20 samples). OA was detected only in 2 out of 13 blood samples (15.4 %) with an average 3.67 ng/mL. Whereas OA was not detected in all analyzed urine samples.  相似文献   
105.
106.
Spectral characteristics of species-specific acoustic signals were analyzed in cats under various unfavourable conditions: hunger, isolation, pain stimulation, agony. The increase in the need to get rid of the discomfort accompanied by the development of emotional excitation was reflected in spectral characteristics of produced signals. The frequency and duration of signals increased, their spectrum widened accompanied by spectral maxima shifted towards the high-frequency area similar to the range of formant frequencies in the signals of newborn kittens. The similarity between spectral characteristics of the above signals in adult and newborn cats might indicate the appearance of infantile features in adult cats under conditions of a marked desire to change the existing situation. The fact that motivational state was reflected in spectral characteristics of acoustic signals along with stable responses to the signals, spoke in favour of a considerable contribution made by communication to the organization of intraspecific relations.  相似文献   
107.
The results of the clinico-laboratory and epidemiological study of a newly developed live measles vaccine obtained from strain Moscow-5, genetically homogeneous and cloned from strain JI-16, are presented. The data indicate that the vaccine obtained from strain Moscow-5 is safe and possesses low reactogenicity and high immunological potency, thus meeting all requirements for vaccinal preparations.  相似文献   
108.
In this work the possibility of using microwaves for immunomodulation in the immunization of animals with thymus-independent antigen was studied. The projection zones of the thymus and adrenal glands of the test animals were subjected to the action of decimeter, or ultrahigh frequency (UHF), waves, while the corresponding zones of the control animals were subjected to imitation UHF irradiation. Vi-antigen was shown to be a thymus-independent antigen for rabbits (according to the results of the evaluation of the functional state of thymocytes, as manifested by the adsorption of acridine orange by the chromatin of thymocyte nuclei and by the content of RNA and DNA in the thymus). The action of UHF waves on the projection zone of the thymus was accompanied by a decrease in the glucocorticoid activity of the adrenal cortex, observed simultaneously with a pronounced immunostimulating effect. The UHF irradiation of the zone of the adrenal glands was accompanied by immunosuppression in combination with enhanced glucocorticoid activity of the adrenal cortex.  相似文献   
109.
110.
The effects of 12 elements on the formation and accumulation of isoquinolines were studied in opium poppy seedlings (Papaver somniferum L.). Three types of concentration dependences of the effects of the elements under study were determined. The elements served as activators (Co, Mo, W, Cr, and Cu) or inhibitors of these processes (B, Fe, V, Mn, and Ca). The molecular mechanisms of action of these regulators are discussed. The optimum concentrations of Co and Mo were tested under combined treatment conditions with these elements.  相似文献   
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