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1.
D Gill 《Experientia》1979,35(3):400-401
Following Hirschfeld et al., dithionite was added to mounting media to inhibit fluorescence fading. Excellent response is reported for fluorescein, acridine orange, 33258 Hoechst, acriflavine, berberine (and ethidium bromide), but not for quinacrine.  相似文献   

2.
Summary Filipin, which interferes with sterol stabilization of phospholipid membrane layers, inhibits the photoperiodic induction of flowering in Xantium; the inhibition is reversed to a large extent by cholesterol.We are thankful to Upjohn Co., Kalamazoo, Mich., USA, for the gift of a sample of filipin used in this investigation.  相似文献   

3.
Summary A definite seasonal change is observed in 2 transaminases, SGOT and SGPT ofR. tigrina. Cold acclimation significantly depresses transaminase activity of serum.Acknowledgments. Thanks are due to Dr M.M. Goil and Dr R. K. Sharma for their invaluable help in various ways. Dr K. Singh would also like to thank S.C.S.T., U.P., for the financial assistance.  相似文献   

4.
Google Trends data is a dataset increasingly employed for many statistical investigations. However, care should be placed in handling this tool, especially when applied for quantitative prediction purposes. Being by design Internet user dependent, estimators based on Google Trends data embody many sources of uncertainty and instability. They are related, for example, to technical (e.g., cross-regional disparities in the degree of computer alphabetization, time dependency of Internet users), psychological (e.g., emotionally driven spikes and other form of data perturbations), linguistic (e.g., noise generated by double-meaning words). Despite the stimulating literature available today on how to use Google Trends data as a forecasting tool, surprisingly, to the best of the author's knowledge, it appears that to date no articles specifically devoted to the prediction of these data have been published. In this paper, a novel forecasting method, based on a denoiser of the wavelet type employed in conjunction with a forecasting model of the class SARIMA (seasonal autoregressive integrated moving average), is presented. The wavelet filter is iteratively calibrated according to a bounded search algorithm, until a minimum of a suitable loss function is reached. Finally, empirical evidence is presented to support the validity of the proposed method.  相似文献   

5.
Summary The cellular distribution of H3-dimetacrine in rat cerebral cortex was studied by electron microscopic autoradiography. A considerable proportion of autoradiographic grains (40.6%) was located over the synaptic areas, while the other structures (i.e., dendrites, axons, glial and neuronal cells) contained less autoradiographic activity.Acknowledgments. The authors wish to thank Siegfried AG., Switzerland, for the generous supply of 3-bromo-dimetacrine. Dimetacrine was kindly donated by Nippon Chemiphar Co., Ltd., Tokyo, Japan.  相似文献   

6.
The concept of conformational control of bond migration in the trnsition state to theD-homo-annulation of 17-hydroxy-20-keto steroids appears to provide a unified rationale for the observed phenomena.Contribution from Merck & Co., Inc., Rahway, N. J., presented before the North Jersey Section of the American Chemical Society byN. L. Wendler as part of a lecture entitledStereochemical Effects Attending D-Ring Rearrangements in Steroids, February 3, 1959.  相似文献   

7.
By means of gas chromatographic and mass spectroscopic methods, and combined GC-electroantennogram and electrosensillogram techniques, (E)-11-hexadecenal and (10E, 12E)-10,12-hexadecadienal [(E,E)-bombykal is also the main constituent of the pheromone of the silver-striped hawk-mothHippotion celerio. The biological activity of the substances was demonstrated with electroantennogram and single cell recording, and the physiological efficacy of the different hexadecadienal isomers compared.Pheromones, 79; as Pheromones, 78 is taken: Wu, Cai-Hong, and Bestmann, H. J., Chinese Science Bulletin34 (1989) 1475; pheromones, 77: Attygalle, A. B., Steghaus0Kovac, S., Ahmed, V. U., Maschwitz, U., Vostrowsky, Ol, and Bestmann, H. J., Naturwissen-schaften78 (1991) 90.  相似文献   

8.
Summary In PCB-treated rats total white cell and differential counts and lymphocyte proliferative response to PWM were unaltered. The lymphocyte response to PHA was increased in treated animals.Acknowledgements. Supported by grants from the Medical Research Council of Canada. We thank the Monsanto Chemical Co., St. Louis, Mo., for donating Aroclor 1254 and Dr.P. Cano for the protein determinations and electrophoresis.  相似文献   

9.
Zusammenfassung Nach Hemmung der Dopaminsynthese beschleunigte Morphin bei Ratten die Abnahme der Dopaminkonzentration im Corpus striatum. Dieser Effekt, der durch Naloxon gehemmt wurde, lässt sich durch eine Erhöhung des Dopamin-Umsatzes im Corpus striatum unter Einfluss von Morphin erklären.

Acknowledgements: The skilful technical assistance of Mrs.H. Kügler is gratefully acknowledged. I am indebted to the Endo Labs., Inc. Garden City, N.Y., USA, for a generous gift of naloxone.  相似文献   

10.
Summary An accessory for a commercial 10-place filtration apparatus is described, which allows the easy recovery of both filter-bound material and flow-through in the study of DNA-protein interactions by assaying binding of protein to cellulose nitrate filters.The technical assistance of Christine Michalowski is gratefully acknowledged., Supported by the Deutsche Forschungsgemeinschaft.  相似文献   

11.
Summary Ecdysterone was found in large amounts in the Mediterranean zoanthidGerardia savaglia both immediately after its collection and after it had been kept for 15 months in an aquarium. This is the first time that an ecdysteroid has been found in a marine animal which does not belong to the phylum Arthropoda.Acknowledgments. We are grateful to Dr E. Volpi, Trento, for collecting, and keeping alive, the zoanthid, and to Prof. L. Rossi, Torino, both for the identification and for useful comments, and to Prof. L. Colombo, Padova, for stimulating discussions. This work was funded by the Provincia Autonoma di Trento, Assessorato Agricoltura e Foreste, within our program for biological control of phytopathogenic fungi, by C.N.R., Roma, and by M.P.I., through the Centro Interuniversitario di Biologia Marina in Livorno.Laboratorio di Chimica.Stazione Sperimentale Agraria.To whom reprint requests should be addressed.  相似文献   

12.
Summary Presynaptic terminals typically contain secretory granules, usually 100–200 nm in diameter, in addition to the smaller synaptic vesicles. Evidence is presented that granule exocytosis is a widespread phenomenon in invertebrate neuropiles. Such secretory release is apparently associated with morphologically unspecialized regions of the plasmalemma, rather than synaptic thickenings.Acknowledgments. The authors gratefully acknowledge the assistance of Mr R. M. Hewit and Mrs. S. Al-Yousuf. Supported by research grant GR/A88743 from the S.E.R.C., U.K., to D.W. Golding.  相似文献   

13.
Neural networks (NNs) are appropriate to use in time series analysis under conditions of unfulfilled assumptions, i.e., non‐normality and nonlinearity. The aim of this paper is to propose means of addressing identified shortcomings with the objective of identifying the NN structure for inflation forecasting. The research is based on a theoretical model that includes the characteristics of demand‐pull and cost‐push inflation; i.e., it uses the labor market, financial and external factors, and lagged inflation variables. It is conducted at the aggregate level of euro area countries from January 1999 to January 2017. Based on the estimated 90 feedforward NNs (FNNs) and 450 Jordan NNs (JNNs), which differ in variable parameters (number of iterations, learning rate, initial weight value intervals, number of hidden neurons, and weight value of the context unit), the mean square error (MSE), and the Akaike Information Criterion (AIC) are calculated for two periods: in‐the‐sample and out‐of‐sample. Ranking NNs simultaneously on both periods according to either MSE or AIC does not lead to the selection of the ‘best’ NN because the optimal NN in‐the‐sample, based on MSE and/or AIC criteria, often has high out‐of‐sample values of both indicators. To achieve the best compromise solution, i.e., to select an optimal NN, the preference ranking organization method for enrichment of evaluations (PROMETHEE) is used. Comparing the optimal FNN and JNN, i.e., FNN(4,5,1) and JNN(4,3,1), it is concluded that under approximately equal conditions, fewer hidden layer neurons are required in JNN than in FNN, confirming that JNN is parsimonious compared to FNN. Moreover, JNN has a better forecasting performance than FNN.  相似文献   

14.
Summary Representative members in each of the four orders of Oomycetes (Phytophthora cactorum, Peronosporales;Lagenidium callinectes, L. giganteum, Lagenidiales;Saprolegnia ferax, Saprolegniales;Apodachylella completa, Leptomitales) have been examined for their ability to synthesize and polycyclize squalene-oxide (SO) to a tetracyclic product and to differentiate between cycloartenol and lanosterol metabolism to sterols.P. cactorum andL. giganteum failed to synthesize or metabolize SO, cycloartenol or lanosterol. While the other three fungi synthesized sterols via SO and lanosterol, a minor metabolism of added cycloartenol to the 4,4-desmethyl-14-methylcyclosteroid dehydropollinastanol was observed.Acknowledgment.Saprolegnia ferax-ATCC 3605 (1),Lagenidium callinectes ATCC 24973 (2),Apodachlyella completa (3) were obtained from Dr J. Aronson, Arizona State Univ. (3),Lagenidium gigateum was obtained from a drainage ditch in California (4), andPhytophthora cactorum was obtained from the U.C. Berkeley Fungal Collection (5). The fungi were cultured as previously described: Cultures 1,2,3: Berg, L. B., Ph. D. dissertation, Univ. of MD., College Park (1983); culture 4: Kerwin, J.L., and Washino, R.K., Exp. Mycol.7 (1983) 109; culture 5: Nes, W.D., and Stafford, A.E., Lipids19 (1984) 544. Preliminary observations involving the labeled substrates were presented by Le, P.H., Nes, W.D., and Parish, E.J. J. Am. Oil Chem. Soc.62 (1985) 655(A). Please address all correspondence to W.D. Nes, Plant Physiology and Chemistry Research Unit, ARS-US Dept of Agriculture, Berkeley, CA 94710, USA.  相似文献   

15.
Summary Hydrostatic pressure applied to isolated eel gills induces changes in the tissue, Na+, K+ and Cl contents. It also inhibits the activity of the (Na++K+) ATPase. Results are discussed in terms of an effect of pressure on the Na+ and Cl pumps and on the passive permeability processes.A. P., Chargé de Recherches du F. N. R. S.; R. G., Chercheur qualifié du F. N. R. S., We are grateful to Prof. A. Distèche and E. Schoffeniels for their advice throughout this work. We also want to thank Mr J. M. Theate and Mrs C. Marchand-Coquay for their valuable technical assistance.  相似文献   

16.
Summary Interactions between germinating spores of phylloplane microfungi andPestalotiopsis funerea Desm., a leaf spot pathogen ofEucalyptus globulus Labill., were studied in vitro. Findings suggest that sporostasis imposed onP. funerea by germinating spores of other nonparasitic microfungi was due to nutrient impoverishment or mycotoxins present in spore exudates.Acknowledgments. Financial assistance in the form of SRF from CSIR, New Delhi is gratefully acknowledged. Thanks are due to Professor R. S. Dwivedi for encouragement.  相似文献   

17.
城市土地集约利用潜力评价信息系统构建浅析   总被引:2,自引:0,他引:2  
城市土地集约利用潜力评价是一项复杂的系统工程。在整合城市规划信息系统、多用途地籍信息系统、房地产开发与管理信息系统、城镇土地定级估价信息系统等的基础上开发城市土地集约利用潜力评价信息系统,可实现此项工作的一期自动化,日常管理更新动态化,从而推动土地工作向科学化、现代化方向发展。  相似文献   

18.
Summary Dechlorinated products were isolated from the urine of rats that were administered chlorobiphenylols, the primary hydroxylated metabolites of PCB in mammals. The mechanism of chlorine loss from chlorobiphenylols is different from the mechanism of dechlorination via arene oxides whereby concomitant hydroxylation is always observed.A fellowship to the first author by the Organisation for the Advancement of Pure Research (stichting Z. W. O., The Netherlands) is gratefully acknowledged.  相似文献   

19.
Summary In vitro and in vivo efficacy data indicate that chemical activity is optimized at the 2 carbon chain length and that these compounds have injectable potency and spectrum of activity against major animal external parasite species.Acknowledgments are due to R.O. Drummond, U.S.D.A., Kerrville, Texas; T.E. Elward, Stanford Research Institute and D.E. Weidhaas, U.S.D.A., Gainesville, Florida.  相似文献   

20.
Hyperlipidemia is a risk factor for atherosclerosis that is characterized by lipid accumulation, inflammatory cell infiltration, and smooth muscle cell proliferation. It is well known that hyperlipidemia is a stimulator for endothelial dysfunction and smooth muscle cell migration during vascular disease development. Recently, it was found that vessel wall contains a variable number of mesenchymal stem cells (MSCs) that are quiescent in physiological conditions, but can be activated by a variety of stimuli, e.g., increased lipid level or hyperlipidemia. Vascular MSCs displayed characteristics of stem cells which can differentiate into several types of cells, e.g., smooth muscle cells, adipocytic, chondrocytic, and osteocytic lineages. In vitro, lipid loading can induce MSC migration and chemokines secretion. After MSC migration into the intima, they play an essential role in inflammatory response and cell accumulation during the initiation and progression of atherosclerosis. In addition, MSC transplantation has been explored as a therapeutic approach to treat atherosclerosis in animal models. In this review, we aim to summarize current progress in characterizing the identity of vascular MSCs and to discuss the mechanisms involved in the response of vascular stem/progenitor cells to lipid loading, as well as to explore therapeutic strategies for vascular diseases and shed new light on regenerative medicine.  相似文献   

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