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1.
Summary The effect of volatile metabolites produced by 8 Aspergilli (i.e.,Aspergillus candidus, A. chevalieri, A. flavus, A. fumigatus, A. nidulans, A. niger, A. ochraceous andA. tamarii) on spore germination were tested againstAuxarthron conjugatum, Chrysosporium pannicola, Keratinomyces ajelloi andMicrosporum gypseum. The volatile metabolites inhibited the spore germination of all the test fungi.Acknowledgment. The authors thank Professor G.P. Mishra for the use of the facilities and S.K.D. acknowledges the fellowship award by I.C.M.R. New Delhi.  相似文献   

2.
Summary Ethidium bromide was fed toD. melanogaster andD. simulans males in order to test its toxic capacity and potency for the induction of dominant lethals. Our results show that ethidium bromide has a high toxicity and likewise produces dominant lethals to a significant extent in both species, but more effectively inD. melanogaster.  相似文献   

3.
This paper proposes a new evaluation framework for interval forecasts. Our model‐free test can be used to evaluate interval forecasts and high‐density regions, potentially discontinuous and/or asymmetric. Using a simple J‐statistic, based on the moments defined by the orthonormal polynomials associated with the binomial distribution, this new approach presents many advantages. First, its implementation is extremely easy. Second, it allows for a separate test for unconditional coverage, independence and conditional coverage hypotheses. Third, Monte Carlo simulations show that for realistic sample sizes our GMM test has good small‐sample properties. These results are corroborated by an empirical application on SP500 and Nikkei stock market indexes. It confirms that using this GMM test leads to major consequences for the ex post evaluation of interval forecasts produced by linear versus nonlinear models. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

4.
Summary L-Ascorbic acid (0.57 mM) and dimethylsulfoxide (14.1 mM) were found to potentiate four times the antibacterial activities of daunomycin and adriamycin in theStaphylococcus aureus test. This effect, however, could not be demonstrated against eukaryotic cells and leukemia P388 in mice. The authors thank Dr A. Maráz, Department of Microbiology, J.A. University, Szeged, and Dr Zs. Somfai, Institute of Oncology, Budapest, for collaboration in the experiments with yeast and tumor cells.  相似文献   

5.
The relationship between the induction of mutant clones and the time of mutagen treatment was studied in the somatic mutation and recombination test (SMART) in wing cells ofDrosophila melanogaster. Larvae trans-heterozygous for the recessive marker mutations multiple wing hairs (mwh) and flare (flr) were produced. Batches of these larvae were then treated with mutagen at different ages spanning all three larval instars. Methyl methanesulfonate was fed acutely for 2 h by immersing the larvae in a solution of the mutagen mixed with powdered cellulose. Wings of the surviving adult flies were mounted and scored for the presence of spots. The frequency and size of single and twin spots were recorded separately. Twin spots are produced exclusively by mitotic recombination, whereas single spots can results from various types of mutational and exchange events. There exists a clear correlation between time of induction and frequency as well as size of the single spots. In young larvae only few but very large spots are induced, whereas in older larvae the frequencies are considerably increased but the sizes are smaller. The twin spots show a different relationship. Practically no twin spots are found in very young and in very old larvae. The results demonstrate that in the wing spot test the optimal age of the larvae for mutagen treatment is 72 h.  相似文献   

6.
Summary A number of experiments all led to the conclusion that the Feulgen reaction is a valuable test for thein situ localization of thymonucleic acid: there is thus no serious reason to doubt that this acid is a constituent of chromatin and chromosomes.  相似文献   

7.
Summary Filtrates fromE. coli H10407 cultures, giving a positive response for heat-labile enterotoxin (LT) in the Y-1 cell test, show an inhibitory activity both on3H-thymidine uptake by Ehrlich ascites cells and on granulocytic-macrophagic precursors (CFU-C) in murine bone marrow.Acknowledgments. We gratefully acknowledge the expert technical assistance of L. Basso and A. Gerosa of Department of Pathology, Hospital of Desio.  相似文献   

8.
Riassunto Emazie umane normali trattate con cefalotina, in opportune condizioni sperimentali, si comportano in alcuni test di emolisi in vitro (test di emolisi acida, test di sensibilità agli isoanticorpi freddi) in modo simile alle emazie della emoglobinuria parossistica notturna (EPN) (emazie simil-EPN). A differenza di altri tipi di emazie simil-EPN, queste emazie danno anche un test di Coombs diretto positivo, di tipo non. Viene avanzata l'ipotesi che la lesione responsabile del comportamento simil-EPN di queste emazie sia da ricercare in una alterazione delle proteine stromali.  相似文献   

9.
The autoregressive conditional heteroscedastic (ARCH) model and its extensions have been widely used in modelling changing variances in financial time series. Since the asset return distributions frequently display tails heavier than normal distributions, it is worth while studying robust ARCH modelling without a specific distribution assumption. In this paper, rather than modelling the conditional variance, we study ARCH modelling for the conditional scale. We examine the L1‐estimation of ARCH models and derive the limiting distributions of the estimators. A robust standardized absolute residual autocorrelation based on least absolute deviation estimation is proposed. Then a robust portmanteau statistic is constructed to test the adequacy of the model, especially the specification of the conditional scale. We obtain their asymptotic distributions under mild conditions. Examples show that the suggested L1‐norm estimators and the goodness‐of‐fit test are robust against error distributions and are accurate for moderate sample sizes. This paper provides a useful tool in modelling conditional heteroscedastic time series data. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

10.
Summary In order to test the possibility for microsomes to multiply like viruses, microsomes of chick liver were inoculated on chorioallantoïc membranes. The glucose-6-phosphatase activity, an enzyme located in the liver microsomes, was determined in the treated membranes. The activity decreased during the first 24 h after inoculation. It reached, after 48 h, from two to six times the value attained after 24 h.A suspension of heated granules, or of heatedTétrahymèna géléii, though producing the same lesions of the membrane, did not increase the phosphatase activity of the microsome fraction after 48 h.The present results are compatible with the idea that liver microsomes multiply by autoduplication.  相似文献   

11.
Summary The presence and distribution of human A, B and H isoantigens were demonstrated in Cynomolgus monkey (Macaca fascicularis) by means of red cell adherence test. Although no human antigens were found on primate erythrocytes, various epithelial tissues revealed the presence of A, B or H antigenic substance. The distribution and localization was similar to that found in human tissues. Majority of specimens from each individual animal possessed only 1 human type isoantigen with the exception of the salivary and sweat glands, where all animals showed the presence of H antigen in addition to other specificity, and of Brunner's gland, where all sections reacted positively also for A antigen.  相似文献   

12.
The COI-COII intergenic region ofApis mellifera mitochondrial DNA contains an important length polymorphism based on a variable number of copies of a 192–196 bp sequence (Q) and the completer or partial deletion of 67 pb sequence (Po). This length variability has been combined with a restriction site polymorphism to produce a rapid and simple test for the characterization of mtDNA haplotypes. This test included the amplification by the polymerase chain reaction of the COI-COII region followed by aDraI restriction of the amplified fragment. In a survey of 302 colonies belonging to 12 subspecies, 21 different haplotypes have been found which have been unambiguously allocated to one of the 3 mtDNA lineages of the species. Although all colonies of lineage C exhibit the same pattern (C1), each one of lineages A and M presents up to 10 different haplotypes, opening the way to studies on the genetic structure and the evolution of a large fraction of the species. This test also differentiates southern Spanish and South African colonies, which can be of great interest for the Africanized bee problem.  相似文献   

13.
The conventional growth rate measures (such as month‐on‐month, year‐on‐year growth rates and 6‐month smoothed annualized rate adopted by the US Bureau of Labor Statistics and Economic Cycle Research Institute) are popular and can be easily obtained by computing the growth rate for monthly data based on a fixed comparison benchmark, although they do not make good use of the information underlying the economic series. By focusing on the monthly data, this paper proposes the k‐month kernel‐weighted annualized rate (k‐MKAR), which includes most existing growth rate measures as special cases. The proposed k‐MKAR measure involves the selection of smoothing parameters that are associated with the accuracy and timeliness for detecting the change in business turning points. That is, the comparison base is flexible and is likely to vary for different series under consideration. A data‐driven procedure depending upon the stepwise multiple reality check test for choosing the smoothing parameters is also suggested in this paper. The simple numerical evaluation and Monte Carlo experiment are conducted to confirm that our measures (in particular the two‐parameter k‐MKAR) improve the timeliness subject to a certain degree of accuracy. The business cycle signals issued by the Council for Economic Planning and Development over the period from 1998 to 2009 in Taiwan are taken as an example to illustrate the empirical application of our method. The empirical results show that the k‐MKAR‐based score lights are more capable of reflecting turning points earlier than the conventional year‐on‐year measure without sacrificing accuracy. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

14.
Summary A new method for the classification of antiphlogistics is described using the growth inhibition ofLactobacillus casei. In this test the fenamic acids and particularly the new class of the Cinnopentazon-antiphologistics (Scha 306, Scha 764 etc.) exhibit bacteriostatic properties of a medium intensity.

Alexander von Muralt zum 65. Geburtstag gewidmet.  相似文献   

15.
Summary The toxic effects of Temik (aldicarb) on a fresh water Himalyan lake teleost,Barbus conchonius were investigated in hard and soft water. The 48-, 72- and 96-h TLm-values in mg/l were 8.99, 2.39 and 2.42 respectively in the hard-water test and 3.30, 0.62 and 0.46 in the soft-water test. The toxicity of Temik toB. conchonius increases many fold in soft water.One of us (S. C. P.) is grateful to U. G. C., for the award of a senior research fellowship.  相似文献   

16.
Summary The proximal half of the A (=X) chromosome ofD. madeirensis has a gene arrangement very similar to the A1 or A6 inversions found inD. subobscura. Polytene chromosome analysis of hybrids betweenD. madeirensis and strains ofD. subobscura homozygous for such inversions shows, however thatD. madeirensis has a gene arrangement different from any known forD. subobscura. These results provide evidence for a greater differentiation of the X chromosome in these species than has previously been described; it seems that the X chromosome is the only one that has undergone structural variation during the speciation process.  相似文献   

17.
Summary Halocyamine A, an antimicrobial substance isolated from hemocytes of the solitary ascidianHalocynthia roretzi, inhibited in vitro the growth of fish RNA viruses (infectious hematopoietic necrosis virus and infectious pancreatic necrosis virus). Pretreatment of RNA virus with halocyamine A reduced the infectivity of the virus toward host cells. The growth of marine bacteria,Achromobacter aquamarinus andPseudomonas perfectomarinus, was also inhibited by halocyamine A but that ofAlteromonas putrefaciens andVibrio anguillarum was not. These results suggest that halocyamine may have a role in the defense mechanisms ofH. roretzi against marine viruses and bacteria.  相似文献   

18.
Summary Spherical structures in the test cells that surround the embryos of the ascidianCiona intestinalis L. (Tunicata, phylum Chordata) were studied by both light and electron microscope. Our data support the view that these structures are microorganism-like cells living in symbiosis with the test cells. Their possible role is discussed.Acknowledgment. The authors are indebted to the Institute of Comparative Anatomy of Palermo for the use of the Zeiss EM 9 Electron Microscope. Particular thanks to Mr Salvatore Bucculeri for his technical assistance.  相似文献   

19.
Structural analogues of syringomycin and syringotoxin were produced by fermentation, characterized by FAB-MS and amino acid analysis and compared to the parent compounds in the antibiosis test againstRhodotorula pilimanae. The C-terminal residue was shown to be important for the activity.  相似文献   

20.
Malaria results in up to 2.5 million deaths annually, with young children and pregnant women at greatest risk. The great majority of severe disease is caused by Plasmodium falciparum. A characteristic feature of infection with P. falciparum is the accumulation or sequestration of parasite-infected red blood cells (RBCs) in various organs, such as the brain, lung and placenta, and together with other factors is important in the pathogenesis of severe forms of malaria. Sequestration results from adhesive interactions between parasite-derived proteins expressed on the surface of infected RBCs and a number of host molecules on the surface of endothelial cells, placental cells and uninfected RBCs. Some receptors for parasite adhesion have been implicated in particular malaria syndromes, such as intercellular adhesion molecule 1 in cerebral malaria and chondroitin sulfate A and hyaluronic acid in placental infection. The principal parasite ligand and antigen on the RBC surface, P. falciparum erythrocyte membrane protein 1 encoded by a multigene family termed var, is clonally variant, enabling evasion of specific immune responses. An understanding of these host-parasite interactions in the context of clinical disease and immunity may reveal potential targets to prevent or treat severe forms of malaria. Received 25 June 2001; received after revision 22 August 2001; accepted 24 August 2001  相似文献   

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