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71.
Two entomogenous fungi, Metarrhizium anisopliae and Beauveria bassiana, were cultured in liquid culture media containing various commercial peptone sources to determine the effect of the sources on growth and sporulation. Each fungus responded differently to the various peptone sources. Tryptone, Casitone, and yeast extract were effective for mycelial growth of M. anisopliae; however, yeast extract was the most effective in production of spores. Soytone Casitone, Neopeptone, and casein hydrolysate were used effectively for mycelial growth of B. bassiana, but the latter two were not as effective for production of spores. Gelatone and Peptone (Bacteriological) were not effective for production of growth or sporulation for either fungus.  相似文献   
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A retrospective study of 250 cadaver kidney transplants was carried out to determine the effects of the agonal period, the warm and cold ischaemic times, and the use of kidneys with vascular anomalies on the primary success and failure and the subsequent level of function of the transplants. Kidneys with vascular anomalies or from non-ventilated donors had a primary failure rate of over 30%, whereas those with normal vasculature or from ventilated donors had a rate of 17%. An initial warm ischaemic time of more than 60 minutes was associated with a primary failure rate of 57% and a cold ischaemic time of over 550 minutes with a primary failure rate of 47%. The interrelationship between the warm and cold ischaemic times in the primary success or failure of the transplants was examined and criteria defined for selecting potentially viable cadaver kidneys for transplantation, as follows: (1) The donor should be (a) ventilated, (b) aged 6-50 years, and (c) have normal ante-mortem renal function and have secreted more than 1-5 1 of urine in the 24 hours before death (or an equivalent volume if the urinary output was recorded for less than 24 hours before death); (2) the kidney should have normal renal vasculature enabling single arterial and venous anastomoses to be performed; (3) kidneys with I.W.I.T.s of longer than 60 minutes should not be used; (4) for kidneys with I.W.I.T.s of less than 20 minutes the C.I.T. is not critical but should not exceed 12 hours; (5) for kidneys with I.W.I.T.s of 20-60 minutes the C.I.T. should not exceed 450 minutes.  相似文献   
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BackgroundSulfadoxine-pyrimethamine (SP) is recommended in Africa in several antimalarial preventive regimens including Intermittent Preventive Treatment in pregnant women (IPTp), Intermittent Preventive Treatment in infants (IPTi) and Seasonal Malaria Chemoprevention (SMC). The effectiveness of SP-based preventive treatments are threatened in areas where Plasmodium falciparum resistance to SP is high. The prevalence of mutations in the dihydropteroate synthase gene (pfdhps) can be used to monitor SP effectiveness. IPTi-SP is recommended only in areas where the prevalence of the pfdhps540E mutation is below 50%. It has also been suggested that IPTp-SP does not have a protective effect in areas where the pfdhps581G mutation, exceeds 10%. However, pfdhps mutation prevalence data in Africa are extremely heterogenous and scattered, with data completely missing from many areas.Methods and findingsThe WWARN SP Molecular Surveyor database was designed to summarize dihydrofolate reductase (pfdhfr) and pfdhps gene mutation prevalence data. In this paper, pfdhps mutation prevalence data was used to generate continuous spatiotemporal surface maps of the estimated prevalence of the SP resistance markers pfdhps437G, pfdhps540E, and pfdhps581G in Africa from 1990 to 2020 using a geostatistical model, with a Bayesian inference framework to estimate uncertainty. The maps of estimated prevalence show an expansion of the pfdhps437G mutations across the entire continent over the last three decades. The pfdhps540E mutation emerged from limited foci in East Africa to currently exceeding 50% estimated prevalence in most of East and South East Africa. pfdhps540E distribution is expanding at low or moderate prevalence in central Africa and a predicted focus in West Africa. Although the pfdhps581G mutation spread from one focus in East Africa in 2000, to exceeding 10% estimated prevalence in several foci in 2010, the predicted distribution of the marker did not expand in 2020, however our analysis indicated high uncertainty in areas where pfdhps581G is present. Uncertainty was higher in spatial regions where the prevalence of a marker is intermediate or where prevalence is changing over time.ConclusionsThe WWARN SP Molecular Surveyor database and a set of continuous spatiotemporal surface maps were built to provide users with standardized, current information on resistance marker distribution and prevalence estimates. According to the maps, the high prevalence of pfdhps540E mutation was to date restricted to East and South East Africa, which is reassuring for continued use of IPTi and SMC in West Africa, but continuous monitoring is needed as the pfdhps540E distribution is expanding. Several foci where pfdhps581G prevalence exceeded 10% were identified. More data on the pfdhps581G distribution in these areas needs to be collected to guide IPTp-SP recommendations. Prevalence and uncertainty maps can be utilized together to strategically identify sites where increased surveillance can be most informative. This study combines a molecular marker database and predictive modelling to highlight areas of concern, which can be used to support decisions in public health, highlight knowledge gaps in certain regions, and guide future research.  相似文献   
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Barnes SA  Knight JS  Gray JC 《Plant physiology》1994,106(3):1123-1129
Tobacco plants (Nicotiana tabacum L.) transformed with sense and antisense constructs of a cDNA encoding the tobacco phosphate-triose phosphate-3-phosphoglycerate translocator (phosphate translocator) were shown to contain altered amounts of phosphate translocator mRNA and protein. Phosphate translocator activity in intact chloroplasts isolated from transformed plants showed a 15-fold variation, from 20% of the wild-type activity in antisense transformants to 300% of the wild-type activity in sense transformants. However, the maximal rates of photosynthesis and the rates of photosynthetic carbon assimilation in ambient CO2 showed no consistent differences between transformants. Starch content was decreased by 20% and total soluble sugars were increased by 20% in leaves of antisense transformants compared to sense transformants. The 40% decrease in the ratio of starch to total soluble sugars in antisense transformants relative to sense transformants indicates that distribution of assimilate between starch and sugar had been altered. However, the amount of sucrose in the leaves was unchanged. The changes in total soluble sugars were accounted for completely by changes in glucose and fructose, suggesting the existence of a homeostatic mechanism for maintaining sucrose concentrations in the leaves at the expense of glucose and fructose.  相似文献   
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A plasma membrane fraction was obtained by the combined use of differential centrifugation and aqueous polymer two-phase partitioning techniques. Vanadate-inhibited ATPase and glucan synthase activities were highly enriched in this fraction, although the presence of ATPase activity which was not inhibited by vanadate, nitrate, molybdate, anyimycin A or azide was also detected. Other intracellular membrane marker activities were present at very low or undetectable levels. A further separation step using Percoll density gradient centrifugation resulted in the separation of a fraction which exclusively contained vanadate-inhibited ATPase activity, and was enriched with silicotungstic-acid-staining membrane material. Latency tests performed on the plasma membrane markers showed that the membrane vesicles were in the right-side-out orientation.  相似文献   
80.
STATUS OF STUDIES ON FOSSIL MARINE MAMMALS   总被引:4,自引:0,他引:4  
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