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1.
The effects of cage fish farming on physico-chemical and bacteriological water quality in Lake Volta, Ghana, were investigated in 2013–2014. Farmed and unfarmed (control) areas of the lake were selected for monitoring. Nutrients, temperature, dissolved oxygen, conductivity, turbidity, pH, total coliforms, Pseudomonas and Vibrio spp. in the water were monitored monthly. Analyses of the water samples were carried out according to standard procedures. Physico-chemical quality of the water in both farm and control sites were within ranges typical of minimally impacted water and did not vary significantly between the two contrasting sites. The bacteriological analysis, however, revealed contamination of the lake water by fish farming. The bacterial counts at the farmed sites were significantly higher (p < 0.05) than those of the control sites, with figures at the farmed sites ranging from 132 to 1 708 cfu 100 ml?1 for total coliforms, 514 to 5 170 cfu 100 ml?1 Pseudomonas spp. and 14 to 516 cfu 100 ml?1 for Vibrio spp. The results suggested that cage fish farming has increased bacterial loads in the lake water, but has had minimal impact on its physico-chemical quality.  相似文献   
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This paper presents a summary of reported cases of Serious Adverse Events (SAEs) following treatment with Mectizan® (ivermectin, Merck, Sharpe &; Dohme) in onchocerciasis mass treatment programs from January 1, 1989 to December 31, 2001 through a passive surveillance system. A total of 207 SAE cases were reported out of approximately 165 million reported treatments delivered during the period under review, giving rise to a cumulative incidence of 1 reported SAE per 800,000 reported treatments. The mean age was 40 years and 70% of the cases were males. The mean time between ivermectin intake and onset of illness was 1 day. For 57% of the cases (n = 118), that was their first exposure to ivermectin. The majority of cases were reported from Cameroon (n = 176; 85%) with peaks in the incidence of SAE reporting in 1989–1991 and 1994–1995 when the program expanded to ivermectin-naïve populations. Fifty-five percent of the cases from Cameroon (i.e. 97 out of 176 cases) were encephalopathic and were reported from the central-southern region of the country; two-thirds of these cases were 'probable' or 'possible' cases of Loa loa encephalopathy temporally related to ivermectin treatment. Reporting bias may explain some but not all of the differences in SAE reporting between the 34 onchocerciasis-endemic countries that have, or have had, mass treatment programs. Further research is needed to understand the apparent clustering of encephalopathy cases in central-southern Cameroon since L. loa infection alone probably does not explain the increased incidence of this type of SAE from this region.  相似文献   
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Vibrio parahaemolyticus is a major pathogen that is mainly associated with seafood and is a global food safety issue. Our objective was to isolate and completely sequence a specific phage against this bacterium. Phage vB_VpaM_MAR is able to lyse 76% of the V. parahaemolyticus strains tested. MAR belongs to the Myoviridae family and has a genome comprised of double-stranded DNA with a size of 41,351 bp, a G+C content of 51.3%, and 62 open reading frames (ORFs). Bioinformatic analysis showed that phage MAR is closely related to Vibrio phages VHML, VP58.5, and VP882 and Halomonas aquamarina phage ΦHAP-1.  相似文献   
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Perfusion of beating false tendons of the dog heart with ionic lanthanum produced drastic but reversible modifications of the excitability and the transmembrane action potential of Purkinje cells. Ultrastructural examination of these cells revealed the appearance of a fine extracellular precipitate detectable on unstained sections. In addition, specimens perfused with La+++ showed a striking increase in the contrast of the sarcolemma, particularly in gap junctions and in pinocytic vesicles. La+++ deposits were restricted to the cytoplasmic leaflets of the sarcolemma; no precipitates were found at the plasma membrane of fibroblasts, endothelial and smooth muscle cells, or unmyelinated nerve fibers present in the same specimens. A selective deposition of La+++ was also observed in the sarcolemma of atrial and ventricular cells of dog, rabbit, and cat hearts, as well as in the membrane of the transverse tubular system of ventricular cells. Both the electrophysiological effects and the ultrastructural membrane deposits produced by La+++ disappeared when the specimens were subsequently perfused with phosphate-containing tyrode solution. These results tend to demonstrate that a distinctive feature of the sarcolemma of mammalian cardiac cells is the presence of regions with a high surface density of binding sites for polyvalent cations.  相似文献   
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Propolis is a multi-functional bee product rich in polyphenols. In this study, the inhibitory effect of Anatolian propolis against SARS-coronavirus-2 (SARS-CoV-2) was investigated in vitro and in silico. Raw and commercial propolis samples were used, and both samples were found to be rich in caffeic acid, p-coumaric acid, ferulic acid, t-cinnamic acid, hesperetin, chrysin, pinocembrin, and caffeic acid phenethyl ester (CAPE) at HPLC-UV analysis. Ethanolic propolis extracts (EPE) were used in the ELISA screening test against the spike S1 protein (SARS-CoV-2): ACE-2 interaction for in vitro study. The binding energy values of these polyphenols to the SARS-CoV-2 spike and ACE-2 protein were calculated separately with a molecular docking study using the AutoDock 4.2.6 program. In addition, the pharmacokinetics and drug-likeness properties of these eight polyphenols were calculated according to the SwissADME tool. The binding energy value of pinocembrin was highest in both receptors, followed by chrysin, CAPE, and hesperetin. Based on the in silico modeling and ADME (absorption, distribution, metabolism, and excretion) behaviors of the eight polyphenols, the compounds exhibited the potential ability to act effectively as novel drugs. The findings of both studies showed that propolis has a high inhibitory potential against the Covid-19 virus. However, further studies are now needed.  相似文献   
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The object was to determine the influence of dietary vitamin E, selenium and their combination on the fatty acid con-tent of erythrocytes, bone marrow and spleen lipids of Akkaraman lambs. After supplementation for 15 days, the amount of all fatty acids was slightly higher (p < 0·05) in the vitamin E as compared to the control group, whereas the amount of longer fatty acids was significantly higher (p < 0·01, p < 0·001) in the selenium and combination groups. On the thirtieth day, the amount of all fatty acids was slightly high (p < 0·5) in all the supplemented groups in comparison with the control group. In the bone marrow lipids, the amount of longer fatty acids was decreased (p < 0·05, p < 0·01, p < 0·001) in the vitamin E and combination groups as compared to the control. Although the amount of some fatty acids was high (p < 0·05, p < 0·01) in the selenium group compared to the control, linoleic (18:2), linolenic (18:3) and the polyunsaturated fatty acids (PUFA) were lower (p < 0·05, p < 0·001). In the spleen lipids, the amount of longer fatty acids was slightly decreased (p < 0·05) in the vitamin E group as compared with the control; however the amount of longer fatty acids was significantly higher (p < 0·05, p < 0·01) in the selenium and combination groups in comparison to the control group. Thus dietary supplementation with selenium was more effective than dietary vitamin E supplementation in altering the fatty acid content of the erythrocyte, bone marrow and spleen lipids. © 1997 John Wiley & Sons, Ltd.  相似文献   
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Cronobacter sakazakii is a pathogen that predominantly infects immunocompromised individuals, especially infants, where it causes meningitis. The genome of lytic C. sakazakii myovirus vB_CsaM_GAP31 has been fully sequenced. It consists of 147,940 bp and has a G+C content of 46.3%. A total of 295 genes, including 269 open reading frames and 26 tRNA genes, were identified. This phage is related to Salmonella phage PVP-SE1 and coliphages vB_EcoM-FV3 and rV5.  相似文献   
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