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Abstract

Diethyl and dibutyl α-anilinobenzylphosphonates and [α-(4-benzeneazoanilino)benzyl]-phosphonates and their new palladium(II) halide complexes were evaluated for their cytostatic and antiviral activity in different cell systems.  相似文献   
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Synopsis Attempts to culture lake sturgeon, Acipenser fulvescens, in the past have generally met with limited success. The Wisconsin Department of Natural Resources has been experimenting with artificial propagation of this species since 1979. The intent has been to develop egg collection and handling techniques, hatching regimes, larva and juvenile diet formulations, and to evaluate juvenile survival after stocking. Eggs were collected by caesarian section and fertilized with milt from ripe males taken during annual sturgeon spawning runs on the Fox and Wolf rivers in central Wisconsin. After insemination, the eggs were treated in a saturated solution of Bentonite clay and transported to the hatchery. Eggs were incubated at temperatures ranging from 13–16° C and embryos began hatching within 4 to 8 days. Hatching success ranged from 42 to 96%. Yolksac absorption was complete within 10 days of hatching. Larvae then became positively phototactic and swam actively as if searching for food. Successful larval diets consisted of live brine shrimp nauplii followed by larger zooplankton, primarily Daphnia sp. Juveniles grew best on diets of live Tubifex sp. and chopped earthworms. Liver, fish mash (ground up trout) and pelleted dry food were poorly accepted. Hatchery reared sturgeon grew more slowly than did wild fish.  相似文献   
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An isolated population of the three‐spined stickleback Gasterosteus aculeatus in Croatia was found to have a high incidence of specimens either having a fourth dorsal spine or showing remnants of a fourth spine. Juvenile individuals showed a 9·4% incidence of a fourth spine. The population was examined for asymmetry of the skeletal defensive complex in order to determine whether the additional spine could be the result of developmental instability, a response to predation or environmental conditions.  相似文献   
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The medium forin vitro culture of green and SANDOZ herbicides-treatedChenopodium rubrum L. plants contained saccharides and hormones in different concentrations. Five days after sowing, the plants were exposed to non-inductive (15 long days—LD) or inductive (6 short days—SD + 9 LD) photoperiodic conditions. The length of hypocotyl and cotyledon blade were measured and percentage of flowering was scored. Gibberellic acid (GA3) stimulated hypocotyl growth of green and photobleached plants under SD and inhibited under LD conditions. Indole-3-acetic acid (IAA) slightly stimulated hypocotyl growth of green plants only under LD conditions. Benzylaminopurine (BAP) inhibited hypocotyl growth regardless of photoperiodic regime. The optimal concentration of glucose or saccharose for flowering in green and SANDOZ-treated plants was 5%. In green SAN 9785-treated plants exogenous saccharides compensated lack of photosynthates to bring about full flowering, but SAN 9789-treated plants needed in addition GA3.  相似文献   
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In vitro culture of long-day plant Chenopodium murale L was established. The effects of photoperiod, glucose and gibberellic acid (GA3) on flowering and growth in vitro were investigated. Oscillatory changes of photoperiodic sensitivity were noticeable with regard to plant age. The plants induced at the phase of the 1st and the 3rd pair of leaves flowered to higher degree than those induced at the phase of 2nd pair. Plants induced at the phase of the 1st pair of leaves flowered to 17 % on 5 % glucose-containing medium and the addition of 5 mg dm-3 GA3 resulted in maximum flowering (43 %). Neither glucose nor GA3 were able to compensate for photoperiodic requirements for flowering. Hypocotyl growth was decreased and the 1st internode elongation and development of leaves were increased due to inductive photoperiodic conditions, as compared to non-inductive ones.  相似文献   
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