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1.
Three isolations of a virus of the Hughes group were obtained from seabird ectoparasites, Ornithodoros (Alectorobius) maritimus, on Great Saltee Island, Ireland. The agent is closely related to Soldado virsu, originally obtained from related ticks near Trinidad, West Indies, and represents the second recorded tickborne arbovirus in Ireland.  相似文献   

2.
Summary Treatment of neonatal mice with an antiviral factor, (AVF), obtained from the leaves ofMelia azederach L. protected them against lethal encephalitis caused by Tacaribe virus inoculation. The degree of protection obtained varied from 66% to 100% depending on the virus dose. Similarly, administration of AVF to nursing mothers protected their offspring from developing virus encephalitis. AVF does not directly inactivate Tacaribe virus; it inhibits an early step (s) in the replication process in cell cultures.Dedicated to Prof. Luis Leloir on his 80th birthday.Acknowledgment. This study was supported by Grant 9353/84 from the Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET), Argentina.  相似文献   

3.
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   

4.
Summary Filtrates prepared from heavily grown agar cultures ofM. pulmonis strain Negroni-52 formed plaques on lawns ofA. laidlawii strain JA1 but not on those ofM. pulmonis strains Ash or Negroni-52. The plaque-forming agent proved to be rod-shaped particles morphologically identical with mycoplasmavirus group 1. Evidence supporting the conclusion that the virus originated from Negroni-52 has been obtained. Electron microscopy revelaed that Negroni-52 is also a carrier of long-tailed phage-like particles.  相似文献   

5.
This essay describes the background and possible reasons for legal intervention in the use of lime in the early bleaching industry and draws on the Statutes at Large and other Acts of Parliament as primary sources. The developing chemical knowledge that may have contributed to the later Acts of repeal is also considered in some detail. The earliest noted prohibition was in 1633 and the years 1823, 1825, and 1828 were important repeal dates. No related legislation later than 1828 has been found. During the period from 1633 to 1828 there were many renewals and modifications to existing laws concerning linen and hempen manufacture; several of these contained subsections regarding bleaching. The considerable number of such Acts may account for the apparent confusion shown by earlier authors on this subject. Furthermore, the various Acts passed by the Irish House of Commons over its lifetime from 1400 to 1800, with its many interruptions, were published in a limited number of editions and are consequently held by few libraries. Ireland instituted its own laws and it was only after the Act of Union in 1800 that matters were dealt with by Westminster. Indeed, earlier historians have not always appreciated that, at certain periods of the history of the United Kingdom, Ireland and Scotland (as well as England) had their own separate parliaments.  相似文献   

6.
Summary of conclusions The seven MS lunar and Paschal tables of De ratione paschali fall into two distinct groups which we have classified as Sirmond-type and Padua-type respectively, and from these we have restored the tables of their archetype. The Sirmond-type tables preserve a unique lunar year, which we term the Anatolian lunar year, and they first emerge in the context of a larger computus which was assembled in southern Ireland c. 658, a copy of which Wilfrid had evidently obtained by the time of the Synod of Whitby. The weight of circumstantial evidence supports the hypothesis that it was he who then instigated the corruption of both the tables and the patristic authorities of De ratione paschali, a copy of which subsequently passed to Bede and thence to the Sirmond group of MSS. The Padua-type tables on the other hand are represented only by the Padua MS, and they appear to have originated from within Insular circles on the Continent. These too were crudely corrupted, first by changing their lunar year from Anatolian to Roman and moving their ferial data from January to December and changing some Paschal data, and then secondly by collation with Sirmond-type tables. In the case of both types the objective was clearly to weaken the relationship between the lunar and Paschal tables and to try and obscure the Paschal principles that they preserve and thereby undermine the position of those followers of the Insular latercus who relied on the authority of De ratione paschali for their Pasch. These conclusions naturally give a rather different colour to the events of Whitby from that given by Bede, who places them completely in a theological context. However in material terms what was really at stake at Whitby was the transfer of the patronage of the entire kingdom of Northumbria from the Celtic to the Roman church. Here then was sufficient motivation to justify the most ruthless of expedients.  相似文献   

7.
Summary The size and morphology of virus particles isolated from citrus red mite (Panonychus citri) are similar to those observed in thin sections. The similarity to the virus particles isolated fromOryctes rhinoceros suggests affinity to theBaculovirus group.Presently at USDA, ARS, Fruit and Vegetable Insect Laboratory, Vincennes, IN 47591.  相似文献   

8.
Treatment of neonatal mice with an antiviral factor, (AVF), obtained from the leaves of Melia azedarach L. protected them against lethal encephalitis caused by Tacaribe virus inoculation. The degree of protection obtained varied from 66% to 100% depending on the virus dose. Similarly, administration of AVF to nursing mothers protected their offspring from developing virus encephalitis. AVF does not directly inactivate Tacaribe virus; it inhibits an early step (s) in the replication process in cell cultures.  相似文献   

9.
The presence of a multidrug resistance (MDR) related protein, P-170, in normal and pathological lymphoid cells has been described. The present report evaluates the expression of themdr 1 gene by using the reverse Polymerase Chain Reaction (PCR) on cells obtained from the thymus and bursa of chicken embryos starting from day 12 until hatching. Results show that the thymic cells are positive from day 12 to the end of the observation period. In contrast,mdr mRNA was detected in the bursa from day 14 to day 17 of embryonic life. Possible relationships between the expression ofmdr and the development of T and B lymphocytes are discussed.  相似文献   

10.
Summary The inhibitory effect of four flavonoid compounds on virus multiplication and their influence on the intracellular cyclic AMP (cAMP) level were studied in cell cultures. Quercetin and quercitrin reduced the yields ofHuman (alpha) herpesvirus 1 (HSV-1) andSuid (alpha) herpesvirus 1 (pseudorabies virus), but hesperidin and rutin had no effect. Further, quercetin and quercitrin elevated the intracellular level of cAMP, whereas hesperidin and rutin did not alter the cAMP level. Both antiviral activity and cAMP-enhancing effect were dependent on the concentrations of the flavonoids, and these effects turned out to be parallel.This study suggests that a relation exists between the antiviral effect and the cAMP-enhancing activity of flavonoids.  相似文献   

11.
Summary Bacterially fermented mistletoe preparations (BFMP) were tested on rat hepatoma tissue culture (HTC) cells and human leukemia Molt 4 cells. A dose-dependent inhibition of the growth rate of the cells was observed. For both cell lines, cytostatic concentrations, expressed in weight of fresh plant, were 0.5 mg/ml culture medium for oak BFMP and 1 mg/ml for apple tree BFMP. However, the action of the two preparations was markedly different on each cell line. Non-viable HTC cells were not stained by trypan blue while non-viable Molt 4 cells were fully colored by this reagent. A lysis of cellular membranes of HTC cells was observed by electron microscopy. Furthermore, oak BFMP inhibited the growth of virus transformed 3T3-SV40 cells more than that of non-transformed 3T3 cells. In contrast to BFMP, non-fermented extracts and a purified mistletoe lectin showed a greater inhibition of the growth of Molt 4 cells than of HTC cells. Samples withdrawn at different times during fermentation gradually lost their inhibitory effect on the growth of Molt 4 cells while their action on HTC cells increased up to the 4th day of fermentation. These results are discussed in relation to the cytotoxic substances of mistletoe already characterized.The bacterially fermented mistletoe preparations, named BFMP in the text, were obtained from the Hiscia Institute, CH-4144 Arlesheim, Switzerland, under the name of Iscador. For oak BFMP, mistletoe was fromQuercus petraea Liebl. andQuercus robur L.; for apple tree BFMP fromMalus domestica Borkh.  相似文献   

12.
Summary Isolates ofTrichoderma spp. from pasture soils of Nova Scotia produce at least 7 toxic peptides, probably related to alamethicin, some of which inhibit the growth of cellulase producing rumen bacteria. One of the peptides has been obtained in crystalline form and crystal data on this material is reported.  相似文献   

13.
Summary Peripheral blood samples of a transplantable guinea-pig leukemia revealed that, only during the terminal stages of the disease, leukemic cells produce virus particles indistinguishable from the RNA tumor viruses of the Retraviridae family genusOncorna virus B.This study was supported partly by the Israel Cancer Association.  相似文献   

14.
Summary LD50 values as well as time-dependent parameters of granulosis virus infections were determined at different times during the last larval instar (L5) of the codling moth,Cydia pomonella L., induced either for pupation or for diapause. A significant increase of tolerance to virus was found in 48-h-old L5 induced for pupation, and 24 h later in L5 induced for diapause.  相似文献   

15.
SV40 was discovered as a contaminate of poliovirus vaccine lots distributed to millions of individuals in the United States between 1955 and 1963 while contaminated vaccine batches were later circulated worldwide. After SV40 was observed to cause in vitro animal and human cell transformations and in vivo tumor formations in animals, the search for a connection between the virus and human malignancies has continued to the present day. Different molecular methods have been used to detect SV40 gene products in a variety of human cancers, though SV40 causality in these tumor types has yet to be established. These data, however, are not without controversial issues related to inconclusive SV40 serological and epidemiological evidence alongside tools and methodologies that may contribute to false-positive results in human specimens. This review will also explore how vaccination against SV40 protein products may be used to help prevent and treat individuals with SV40-expressing cancers. Received 19 September 2006; received after revision 8 November 2006; accepted 13 December 2006  相似文献   

16.
Summary Pretreatment with BCG yielded a high degree of protection against experimental vaccinia virus infections in mice.Corynebacterium parvum andAristolochia acid were less protective; other immunostimulants were ineffective.  相似文献   

17.
Summary Crude coralloid root extract ofCycas revoluta showed significant antiviral activity against viruses of the tomato plant (PVX, PVY, TMV, TAV and TRSV) when applied 24 h before virus inoculation, or when mixed with different virus inocula before virus inocultion, in hypersensitive and systemic hosts. No such inhibition was observed when extract was applied 24 h after virus inoculation. TAV did not show any inhibitory response in a systemic host.Authors are thankful to Dr S. N. Gupta and Dr (Smt.) K. Shukla for their valuable guidance and providing laboratory facilities and U.G.C. for financial assistance.  相似文献   

18.
Zusammenfassung Das Verhältnis nicht-enzymatischer Verwandlung von Glutamin zu Ammoniak wird gesteigert, wenn pH, Temperatur und Phosphatmenge vermehrt werden. Bei alkalischer Probe bemerkt man eine Verringerung von Glutamin.

This work was supported by a grant from the Medical Research Council of Ireland.

Miss G. W.Warner was a recipient of a Medical Research Council of Ireland summer student fellowship during the performance of some of this work.  相似文献   

19.
Bovine enteric Corona virus (BEC) multiplies spontaneously with very high efficiency in HRT 18 cells; this line established from human rectum adenocarcinoma presents some properties of the differentiated brush border cell of the intestinal villi. Titers obtained are very high (5 x 10(7) TCID 50/ml virus strain F15). The virus produced had the characteristic of BEC: shape, spikes, density 1.19, hemadsorption and hemagglutination of rat erythrocytes. Human and dog enteritic corona viruses replicate also in HRT 18 cells.  相似文献   

20.
The effect of corticotropin-releasing factor (CRF) and pro-opiomelanocortin (POMC)-derived peptides on hemocyte phagocytosis in two molluscs,Planorbarius corneus andViviparus ater was studied. The peptides and related fragments examined are those which have been shown to influence hemocyte motility in the two species. The results obtained revealed that the effects on phagocytosis are not directly correlated with previous findings on cell motility. Furthermore, the mode of action of an individual peptide could be species-specific and dose-dependent. The relationships between peptides, locomotion and phagocytosis in these molluscs are discussed.  相似文献   

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