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111.
112.
The liver and kidney of rat underwent severe histopathological lesions when treated with a single bolus dose of carbendazim, a fungicide, particularly affecting the hepatocytes and the renal corpuscles, respectively. The effects appear to be manifestations of the microtubule-disrupting activity of carbendazim. Treatment of carbendazim-treated rats with the powder of tuberous root of Withania somnifera (Ashwagandha) for 48 days resulted in complete cure of these organs. The results indicate that Withania somnifera would be an effective curative for carbendazim-induced histopathological changes in the liver and kidney. 相似文献
113.
A. B. Savin 《Journal of Ichthyology》2012,52(7):449-462
Biomass of bottom and near-bottom fishes in the eastern Sea of Okhotsk has been calculated using results of a bottom trawl survey performed in the summer 2010 through depths of 200?C1000 m. Obtained data are compared with the results of investigations performed in compatible water areas during the same season of 1989 and 1997. Biomass variability patterns of major species have been revealed for the period of more than two recent decades. The bathymetric and spatial distribution of major fish species has been revealed using the modern information. Species are listed whose commercial catches could be enlarged. 相似文献
114.
Bertin N.; Guichard S.; Leonardi C.; Longuenesse J. J.; Langlois D.; Navez B. 《Annals of botany》2000,85(6):741-750
Changes in yield and quality of fresh tomatoes in response toair vapour pressure deficit (VPD) and plant fruit load werestudied under Mediterranean summer conditions. Plants thinnedto three or six fruits per truss were grown in two compartments,one at a VPD below 1.5 kPa, the other without VPD control. Theseasonal trend in fruit yield and quality was assessed fromApril to September by weekly measurement of number, fresh weightand dry matter content of harvested fruits, together with theoccurrence of blossom-end-rot (BER) and cracking. On two occasions,in July and September, sugar and acid content was measured atthree ripening stages. The seasonal decrease in fresh yieldwas attenuated at low VPD, because of higher individual fruitfresh weight, especially at low fruit load. Low VPD decreasedoccurrence of BER but like low fruit load, it increased fruitcracking. Fruit dry matter content was lower at low VPD, butwas unaffected by fruit load. Sugar content and the ratio ofsugars:acids was increased at high VPD and low fruit load, withinteractive effects depending on season and ripening stage.The influence of VPD on acid content differed with fruit loadand also changed during ripening and between seasons. Resultsshowed that water was the main limiting factor for growth offruits picked in July; at this time, reducing fruit load topromote mean fruit size had negative effects on BER and cracking.Reducing VPD reduced BER but had a negative effect on crackingand diluted both the dry matter and sugar content. For fruitsharvested later in summer, these negative effects were attenuatedbecause fruit growth was also carbon limited. Copyright 2000Annals of Botany Company Lycopersicon esculentum Mill., tomato, water and carbon stress, yield, quality, dry matter, sugar, acid, BER, volatile composition 相似文献
115.
Cyanobacteria are prominent constituents of the marine biosphere that account for a significant percentage of oceanic primary productivity. In an effort to resolve how open-ocean cyanobacteria persist in regions where the Fe concentration is thought to be limiting their productivity, we performed a number of Fe stress experiments on axenic cultures of marine Synechococcus spp., Crocosphaera sp., and Trichodesmium sp. Through this work, we determined that all of these marine cyanobacteria mount adaptive responses to Fe stress, which resulted in the induction and/or repression of several proteins. We have identified one of the Fe stress-induced proteins as an IdiA homologue. Genomic observations and laboratory data presented herein from open-ocean Synechococcus spp. are consistent with IdiA having a role in cellular Fe scavenging. Our data indicate that IdiA may make an excellent marker for Fe stress in open-ocean cyanobacterial field populations. By determining how these microorganisms respond to Fe stress, we will gain insight into how and when this important trace element can limit their growth in situ. This knowledge will greatly increase our understanding of how marine Fe cycling impacts oceanic processes, such as carbon and nitrogen fixation. 相似文献
116.
K. H. Jang J. W. Seo K. B. Song C. H. Kim S. K. Rhee 《Bioprocess and biosystems engineering》1999,21(5):453-458
Secretion of levansucrase from Zymomonas mobilis in Escherichiacoli by glycine supplement was investigated. A significant amount of levansucrase (about 25% of total activity) was found in intact whole-cells. Cell fractionation experiments showed that levansucrase was found both in the periplasmic space and in the cytoplasmic fraction of E. coli. None or only trace amounts of levansucrase was detected in the extracellular culture broth at 24 h of cultivation and it accrued with the increasing concentration of glycine in the culture medium and duration of the culture period. Optimal glycine concentration for the maximum secretion of levansucrase was in the range of 0.8-1%, in which approximately 20-50% of levansucrase was released into the extracellular fraction at 24 h of cultivation, although glycine retarded the bacterial growth. 相似文献
117.
118.
C. Minard-basquin C. Chaix C. Pichot B. Mandrand 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1285-1287
Abstract A new strategy has been developed to obtain polymer-ODN conjugates. However, free ODN appeared to contaminate synthesis. Various hypotheses are described herein to explain this side reaction. 相似文献
119.
Thomas A. Worthington Shannon K. Brewer Nicole Farless Timothy B. Grabowski Mark S. Gregory 《PloS one》2014,9(5)
Habitat fragmentation and flow regulation are significant factors related to the decline and extinction of freshwater biota. Pelagic-broadcast spawning cyprinids require moving water and some length of unfragmented stream to complete their life cycle. However, it is unknown how discharge and habitat features interact at multiple spatial scales to alter the transport of semi-buoyant fish eggs. Our objective was to assess the relationship between downstream drift of semi-buoyant egg surrogates (gellan beads) and discharge and habitat complexity. We quantified transport time of a known quantity of beads using 2–3 sampling devices at each of seven locations on the North Canadian and Canadian rivers. Transport time was assessed based on median capture time (time at which 50% of beads were captured) and sampling period (time period when 2.5% and 97.5% of beads were captured). Habitat complexity was assessed by calculating width∶depth ratios at each site, and several habitat metrics determined using analyses of aerial photographs. Median time of egg capture was negatively correlated to site discharge. The temporal extent of the sampling period at each site was negatively correlated to both site discharge and habitat-patch dispersion. Our results highlight the role of discharge in driving transport times, but also indicate that higher dispersion of habitat patches relates to increased retention of beads within the river. These results could be used to target restoration activities or prioritize water use to create and maintain habitat complexity within large, fragmented river systems. 相似文献
120.
R H Ward B Modell M Petrou F Karag?zlu E Douratsos 《BMJ (Clinical research ed.)》1983,286(6377):1542-1544
Samples of chorionic villi were obtained in the first trimester by aspiration using a cannula passed transcervically under the guidance of real time ultrasound. In initial studies in 47 anaesthetised patients immediately before therapeutic abortion a method was developed giving a success rate of 89%. In 10 patients successful sampling was performed as an outpatient procedure without anaesthesia. In all, seven diagnostic procedures were undertaken and four of the five unaffected pregnancies continued. The technique of chorionic villous sampling using real time ultrasound is simple to learn and yields material for biochemical analysis and chromosomal study without the need for tissue culture. The exact obstetric risk, however, remains to be defined. 相似文献