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961.
T M Zh?ltikova A D Petrova-Nikitina A Kh Kanchurin V M Berzhets I L Muzyl?va 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1987,(3):4-21
Paper is the second part of the literature review on house dust mites (including 1985). It deals with the diagnosis of the dust mite allergy, the nature of the mite allergens, distribution and population density of the mites in various premises, seasonal population dynamics and population age structure of the dermatophagoid mites, life cycle and breeding of Dermatophagoides pteronyssinus and D. farinae on different food substrates. The methods of the house dust mite control are discussed. The original data on the house dust mite distribution in Moscow is shown. A comparative estimation of the results of mite antigens in the house dust discovering by the acarological and three immunological methods are given. 相似文献
962.
Characterization of the toxicity and cytopathic specificity of a cloned Bacillus thuringiensis crystal protein using insect cell culture 总被引:8,自引:2,他引:6
An insecticidal protein gene from Bacillus thuringiensis var. aizawai was cloned in Escherichia coli. The cloned gene expressed at a high level and the synthesized protein appeared as an insoluble, phase-bright inclusion in the cytoplasm. These inclusions were isolated by density gradient centrifugation, the isolated protein was activated in vitro by different proteolytic regimes and the toxicity of the resulting preparations was studied using insect cells grown in tissue culture. The inclusions consisted of a 130 kDa polypeptide which was processed to a protease-resistant 55 kDa protein by tryptic digestion. This preparation lysed lepidopteran (Choristoneura fumiferana) CF1 cells but not dipteran (Aedes albopictus) cells. When the crystal protein was activated by sequential treatment, first with trypsin and then with Aedes aegypti gut proteases, the resulting 53 kDa polypeptide was now toxic only to the dipteran cells and not to the lepidopteran cells. Thus the dual specificity of this var. aizawai toxin results from differential proteolytic processing of a single protoxin. The trypsin-activated preparation was weakly active against Spodoptera frugiperda cells. Membrane binding studies of the trypsin-activated toxin revealed a 68 kDa protein in the lepidopteran cell membranes, which may be the receptor for this toxin. 相似文献
963.
Jerzy Trojanowski Aloys Hüttermann Konrad Haider Joseph G. H. Wessels 《Archives of microbiology》1985,140(4):326-330
Protoplasts from a lignolytic fungus Fomes annosus were prepared through enzymatic hydrolysis of mycelium utilizing Novozym, a wall lytic enzyme preparation. Isolated protoplasts and living mycelium were compared in their ability to degrade 14C-labelled lignin related phenols and dehydropolymers of labelled coniferyl alcohol (synthetic lignin). The amounts of 14CO2 released from O14CH3-groups, 14C-2-side chains and 14C-rings by protoplasts was in the same range as those for intact mycelium. The methoxyl groups of synthetic lignin were more rapidly metabolized by protoplasts than by mycelium. When calculated in dpm of released 14CO2 per mg protein the decomposition of 14C-labelled synthetic lignin and lignin-related monomers in a hyphae-free system of protoplasts was considerable higher than that obtained by the intact mycelium. The presence of intact hyphae is thus not necessary for lignin degradation to occur.Non-common-abbreviations used DHP
Dehydropolymer of coniferyl alcohol
- LS
lignosulfonates prepared from DHP 相似文献
964.
Mutagenic effect of thioTEPA applied at a dose of 1.25 mg/kg was studied in late spermatids of C57BL/L male mice. The mutagen induced dominant lethal mutations in germ cells (39%) and symmetric translocations in 33.5% of F1 male offspring. The common frequency of sperms with chromosome mutations was 60%, that is ten times as much as the mutagenic effect in bone marrow cells. 39% of embryos at 3.5 days of development died or delayed their development at 2--22 blastomers stages. Structure chromosome aberrations were found in the cells of such embryos. The scheme of genetical screening of chemical compounds in laboratory mice, based on the data obtained early and in the present experiment, is proposed. 相似文献
965.
M R Lichinitser I V Assekritova V A Gorbunova S A Arseri? Kh M Vaarik 《Antibiotiki》1978,23(5):453-457
Karminomycin was used for the treatment of cases with disseminated cancer of the mammary gland in doses of 5 mg/m2 of the body surface intravenously every day for 5 days (15 patients) or 6 mg/m2 twice a week for 2-3 weeks (30 patients). Partial remission or diminution of the tumor size at least by 50 per cent was observed in 26 and 17 per cent of the patients respectively. The remission duration was from 2 to 6 months. With the use of the shortperiod scheme the frequency of the direct side reactions increased. Leucopenia as a side effect was registered in 100 and 40 per cent of the patients and thrombocytopenia was registered in 18 and 3 per cent of the cases respectively. 相似文献
966.
Regeneration and reorganization of the proximal cut end of the pituitary stalk is demonstrated in Ompok bimaculatus with the aid of in situ staining technique. The lesioned end exhibited an increase of axonal density and some axons became prominent by their uncontrolled growth. In few instances the cut ends were reorganized into a neurohypophysis-like organ. 相似文献
967.
V G Morozov V Kh Khavinson N V Il'in 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1978,(7):61-65
Lowmolecular factor of polypeptide nature (thymarin) was extracted from calf thymus. This factor differed by physical and chemical characteristics from thymosin. The percentage content of "active" T-lymphocytes increased under the effect of thymarin in the cultures of lymphoid cells obtained from healthy individuals. The total T-cell count remained unchanged. Thymarin favoured increase of the total T-lymphocyte and "active" T-lymphocyte count in the cultures of cells from patients with chronic inflammatory processes. Cellular immunity reactions were restored and the course of the main disease improved under the effect of parenteral administration of thymarin. It is supposed that T-immunity system incompetence was associated with the inadequate production of the thymus factor capable of restoring the activity of the thymus-dependent lymphocyte population. 相似文献
968.
The marine, mobile, peritrichous ciliate Urceolaria convexa n. sp., a harmless ectozoon on Anaitides mucosa (Oerstedt, 1843), is described from the coast of the Northsea near Büsum (FRG). It is characterized by its bellied lateral walls and the dome shaped peristome (name), which is clearly separated from the body. The adoral cilia describes slightly more than a full circle (400°) and extends nearly horizontally. The height of Urc. convexa n. sp. varies between 27 and 35 µm, the diameter between 32 and 56 µm, The macronucleus has roughly the form of the letter H.
Zoologisches Institut and Zoologisches Museum der Universität Hamburg, (Geschäftsführender Direktor: Prof. Dr. W. Villwock) 相似文献
969.
Oxyhaemoglobins of six digenetic trematodes,--Srivastavaia indica, Gastrothylax crumenifer, Gigantocotyle explanatum, Fasciolopsis buski, Gastrodiscoides hominis, Isoparorchis hypselobagri, and of their 3 vertebrate hosts, Bubalus bubalis, Sus scrofa, Wallago attu, were subjected to alkali denaturation at a pH of 12.4. All oxyhaemoglobins from trematodes and their hosts differ from each other in the rate and extent of alkali denaturation which may be explained due to variations in the amino acid sequences of a particular haem protein in addition to other factors. 相似文献
970.
Marina?I.?OrlovaEmail author Thomas?W.?Therriault Pavel?I.?Antonov Gregory?Kh.?Shcherbina 《Aquatic Ecology》2005,39(4):401-418
Two invasive freshwater mussels, Dreissena rostriformis bugensis (quagga mussel) and D. polymorpha (zebra mussel), reveal differences in patterns and timing of their invasions in Europe. They belong to different clades in
Dreissena phylogenetics: D. rostriformis bugensis genetically is coupled with the brackish water, lacustrine D. r. distincta and the two are believed to represent a single species. As such, the guaqqa mussel has environmental requirements that differ
from the congeneric D. polymorpha. D. rostriformis bugensis invasions were confined to reservoirs of the Dnieper, Don and Dniester Rivers of the Black Sea basin. We recorded D. r. bugensis outside the Black Sea basin for the first time between 1992 and 2001, along the Volga River reservoir cascade including the
Northern Caspian Sea shallows. This represents a 40-year invasion time lag since an invasion corridor through the Volgo-Don
Waterway was established in 1952 (a corridor used extensively by many invertebrate species from the Black Sea region). We
attribute the postponed invasion of Europe by D. r. bugensis, including peculiarities in establishment and its absence in fossil records, to its phylogenetically close relationship with
D. r. distincta and its recent evolutionary origin. The relatively rapid range expansion of D. r. bugensis in eastern Europe during the past several decades was facilitated by human-mediated ecosystem transformation, notably impoundment
of large eastern European rivers, that have allowed this species to utilize newly transformed ecosystems. 相似文献