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231.
232.
Heydenius dominicus n. sp. is described as a new species of fossil mermithid nematode from Dominican Republic amber. The species is represented by two specimens of parasitic juveniles that left their insect host and became embedded in the resin. The nematodes are associated with an adult male limoniid (Diptera: Limoniidae) and an adult female mosquito (Diptera: Culicidae). The parasites are thought to have emerged from the mosquito host. This is the first report of a fossil mermithid from a Neotropical area. 相似文献
233.
George M. White 《Cell biochemistry and biophysics》1987,11(1):25-33
Computers, the human mind, and social systems have common problems of inadequate memory and insufficient data manipulation
speed. In each of these domains, information compression techniques have evolved to reduce storage and processing needs. Among
the techniques for information compression, coding of information in procedures stands out as exceptionally powerful. Procedural
information coding also gives rise to behavior that may be defined as intelligent. It is found in the human mind, in machines
and in social systems. Its use in human thought is aided by language development which promotes regular review of abstract
procedures. A practical consequence of better understanding of procedural information coding is the possibility of training
people to exhibit greater mental capacity, a controversial possibility. This paper explores the impact of data processing
resource limitations, data compression and procedural thinking in men and machines. 相似文献
234.
235.
We have provided data relating Cd concentration in tissue to about a 40-fold range in blood Cd concentration. Osmotic pumps containing cadmium chloride were subcutaneously implanted in male New Zealand white rabbits. The pumps continuously delivered either 0.15 or 1.5 mg Cd/d. Blood and plasma levels of Cd were measured weekly throughout the study. After 28 d, the rabbits were killed and tissue concentrations of Cd determined by atomic absorption spectrophotometry. Less than 10% of the total Cd in the blood was carried in the plasma, the remainder was associated with the blood cells, where it was bound mainly to metallothionein. We found the blood and tissue levels of Cd were correlated for each tissue we investigated. There was a wide range in affinity of the tissues for Cd; liver and kidney had the highest Cd uptake, whereas brain affinity was about 500 times less than liver. 相似文献
236.
Summary Two new species of the Mermithidae (Nematoda) are described from the Japanese blackfly Simulium japonicum Matsumura. They are the first representatives of Gastromermis and Isomermis from Japan. Gastromermis mesostoma n. sp. is characterized by a terminal or near terminal mouth, 6 hypodermal cords and the absence of cloacal or vulvar lips.
Isomermis bipapillatus n. sp. is characterized by the small size of the spicules, their curved shape and by a pair of terminal hypodermal protuberances
in the tail.
This work was in part supported by a grant (No. 58570188) from the Japanese Ministry of Education, Science and Culture
This work was in part supported by a grant (No. 58570188) from the Japanese Ministry of Education, Science and Culture 相似文献
237.
Every week, for 20 weeks, the growth of naturally occurring grain storage fungi on wheat infested with the three commonest British grain storage mites,Acarus siro, Glycyphagus destructor andTyrophagus longior, was compared with that on uninfested wheat.The number of colonies of theAspergillus glaucus group per gram were always less on grain infested with mites than on uninfested grain.Penicillium spp. were also less numerous on grain which was infested withA. siro but did not appear to be affected by the other mites. In contrast, two fungi which are pathogenic to mites,Aspergillus restrictus andWallemia sebi, were more abundant in the presence of certain mites. The former was associated withG. destructor, the latter withG. destructor andA. siro.The three species of mites either feed on theA. glaucus group andPenicillium spp., or inhibit them by an unknown secretion. Pathogenic fungi are probably avoided. Mites are therefore an important variable in studies on fungal growth during grain drying and storage. 相似文献
238.
Three fungicides, chlorothalonil, dichloran and mancozeb were studied to determine the effects on growth and production of roridin E by Myrothecium roridum in vitro. With increasing concentrations of fungicides, both growth and production of roridin E were inhibited. Of the three fungicides, chlorothalonil was much more effective in the inhibition of growth and production of roridin E, than dichloran and mancozeb. 相似文献
239.
Thirty-nine isolates of Cryptococcus neoformans, nineteen serotype AD and twenty serotype BC, were assayed for susceptibility to eight antifungal agents using an in vitro agar dilution assay. Media employed were Kimmig agar and yeast nitrogen base supplemented with 10% glucose. The antifungal agents used were ketoconazole, amphotericin B, 5-fluorocytosine, nystatin, miconazole, BAY N 7133, ICI 153,066, and itraconazole. No clinically significant differences in in vitro minimum inhibitory concentrations were detected between serotypes AD and BC against any of the compounds tested. An adverse medium effect was observed in two of the assays, but the outcome of the AD/BC comparison was not affected. This is the first report in which the in vitro antifungal susceptibilities of Cryptococcus neoformans serotypes are analyzed. 相似文献
240.
Gabriella Fóris MD PhD George A. Medgyesi Mátyás Hauck 《Molecular and cellular biochemistry》1986,69(2):127-137
Summary Met-enkephalin (ME) exerts a bimodal effect on functional activities of rat peritoneal macrophages (PM); in a range of low concentration (10-9-10-7 M) antibody dependent cellular cytotoxicity (ADCC)was markedly stimulated with a simultaneous decrease of Fc receptor (FcR) mediated phagocytosis while the opposite was observed at 10-6-10-5 M concentrations.Studying the possible underlying mechanism(s) the followings were recorded: (1) ME in all applied concentrations induced an early Na+ influx which was followed by a Ca2+ efflux in the range of low concentrations. In the range of high concentrations Na+ influx was accompanied by a Ca2+ influx. (2) ME at 10-8 M concentration induced a rise in cGMP level with a plateau in the 60–120th min of incubation. This effect was prevented by 10-5 M of naloxone. At 10-6 M concentration a transient rise of cAMP level was recorded which was not affected by naloxone. (3) Verapamil in 10-6 M abolished both the Ca2+ influx and the rise in cAMP level induced by 10-6-10-5 M ME but not the rise in cGMP level induced by lower ME concentrations. (4) cAMP elevation by high ME concentrations was abolished by enkephalinase inhibitory puromycin. (5) PM-enkephalinase as assessed by the cleavage of fluorogenic substrate L-alanine beta naphthylamide (ABNA), was inhibited by 10-6-10-5 M of ME. This inhibition was abolished by verapamil, but not affected by naloxone. In the range of low concentrations ME appears to act on specific delta opioid receptors and its action is positively coupled to guanylate cyclase. In relatively higher concentrations ME-action is not mediated by specific delta opioid receptors and it appears to involve Ca2+ influx, adenylate cyclase activation as well as the processing of hormone by PM-enkephalinase. 相似文献