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211.
The Asian tiger mosquito Stegomyia albopicta (= Aedes albopictus) (Diptera: Culicidae), native to Asian forests, is a nuisance mosquito and is responsible for the transmission of arboviruses of public health importance, such as dengue, chikungunya and Zika viruses. It has colonized parts of all continents, except Antarctica, over the past 30–40 years. However, to date, the only records of S. albopicta in North Africa refer to occasional collections in 2010 and 2014 in Algeria. In early September 2015, S. albopicta larvae and adults were collected in a district of Rabat, Morocco. Morphological identification was confirmed by molecular analysis. This is the first record of this invasive mosquito in Morocco. A national surveillance programme will be implemented in 2016 to establish its geographical distribution in Morocco and to instigate control measures to prevent the establishment of new populations and the transmission of arboviruses.  相似文献   
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Pure and partial agonist antioestrogens, exemplified by ICI 164,384 and tamoxifen or 4-hydroxytamoxifen (4'-OHT) respectively, differ in their capacity to inhibit the growth of MCF-7 human breast cancer cells. Under basal conditions which maintain but do not permit proliferation of MCF-7 cells, growth rate was enhanced by oestradiol, Phenol Red, insulin and 4'-OHT but not by ICI 164,384. Oestradiol and insulin together enhanced cell growth rate synergistically. 4'-OHT, but not ICI 164,384, similarly increased insulin-stimulated cell growth in the absence of oestradiol. ICI 164,384 blocked the stimulatory action of 4'-OHT. The stimulatory effect of the peptide growth factors TGF-alpha and IGFI on MCF-7 cells were attenuated by ICI 164,384 and 4'-OHT; ICI 164,384 was more effective than 4'-OHT. The antiproliferative action of ICI 164,384 on oestradiol or growth factor stimulated MCF-7 cells was only weakly inhibited by TGF-beta antibodies.  相似文献   
214.
During the screwworm eradication programme in Libya in 1991, trapped specimens of Cochliomyia hominivorax (Coquerel) were found infested with phoretic mites, Macrocheles muscaedomesticae (Scopoli), or parasitic mites, Trichotromidium muscarum (Riley). The possible sources of infestation and potential effects of mites on screwworm flies are discussed.  相似文献   
215.
ABSTRACT. We demonstrated here the presence of proteins antigenically related to human erythroid spectrin in the parasitic protozoan Toxoplasma gondii . A high molecular weight doublet (M, 245-240,000), present in equimolar ratio, and low molecular weight polypeptides (M, 75,000) were reacted with monoclonal and polyclonal anti-human erythroid spectrin antibodies on electroblotted nitrocellulose sheets. Indirect immunofluorescence assay clearly showed that these proteins were localized in the anterior pole of the organism. Immunogold staining further revealed specific labeling of conoid, rhoptries, micronemes, and dense granules of the apical complex. The presence of the M, 245–240,000 doublet and the M, 75,000 spectrin-like proteins in the anterior pole of T. gondii may probably be consistent with a structural stabilizer function in its organciles which are suspected to be involved in the process of host cell invasion.  相似文献   
216.
Novel steroidal pure antiestrogens   总被引:6,自引:0,他引:6  
A series of steroidal estrogen antagonists with no intrinsic estrogenicity in rat uterotrophic-antiuterotrophic tests has been discovered. The compounds are derivatives of estradiol containing amidoalkyl side chains at the 7 alpha-position. The most potent compounds are N-n-butyl-N-methyl-11-(3,17 beta-dihydroxyestra- 1,3,5(10)-trien-7 alpha-yl) undecanamide and N-2,2,3,3,4,4,4-heptafluorobutyl-N-methyl-11-(3,17 beta-dihydroxyestra- 1,3,5(10)-trien-7 alpha-yl) undecanamide. Structure activity relationships are discussed.  相似文献   
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Abstract. The overall prevalence of Theileria species, mainly, if not exclusively, T.annulata, in 901 Hyalomma detritum detritum collected from cattle in the Doukkala region of Morocco over a period of 2 years was 21.5%. The quantity of infection (number of sporoblasts per infected tick) followed the negative binomial distribution with between one and 250 sporoblasts per infected tick. Infected ticks were found in eight of fourteen areas examined whilst T.annulata was present in all fourteen. There were significant differences in both the prevalence and the quantity of infection between ticks collected from different farms, and between nymphs collected in the autumn from these farms, and moulted in the laboratory, and adults collected in the following summer. The prevalence, but not the quantity, of infection was higher in female than in male ticks. No correlations were established between infection of engorged nymphs and the breed, sex and Theileria piroplasm parasitaemia of the host animal. However, calves infected a greater proportion of nymphs than adult cattle and the heavier the infestation of nymphs on an animal, up to a plateau, the higher the prevalence of infection in those nymphs. There were no differences in infection between ticks moulted at 24oC and 37oC, after the engorged nymphs had been stored at 18oC to simulate over-wintering.  相似文献   
219.
Totally 39% out of 8371 feed and their component samples were contaminated by aflatoxin B1. Mean contamination was 36μg/kg with maximum yield 10100 μg/kg. Contamination of samples by total count of organisms, mean contamination and maximum yield, respectively was: 1) bacteria 99%, 2.2×106, 2.4×108; 2) proteolytic bacteria 94%, 1.2×105, 3.0×106;3) moulds 98%, 1.3×105, 9.0×106; 4) yeasts 44 %, 3.3×104, 3.6×106. The samples were contaminated in 92 % byAspergillus spp, in 71% byAspergillus flavus, in 83% byPenicillium spp, and in 20% byFusarium spp with mean contamination 8.3×104, 1.1×103, 4.2×104, 5.0×103 , and maximum yield 6.8×106, 1.0×105, 5.0×106, 1.5×106, respectively. Totally 8.5% of strains were aflatoxinogenic and 4.4% of the strains were isolated from feed and 21 % of the strains from grain/nut.  相似文献   
220.
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