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51.
E.H. Appleman B.S. Sachais R. Patel K.J. Drobatz R.P. Groman D.R. Kennedy P.A. O'Donnell C. Bryan M.B. Callan 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(1):138-145
Background: Platelet cryopreservation allows long-term storage and immediate availability of transfusion products.
Hypothesis: The addition of a preparation inhibiting platelet activation (Thrombosol, in 2% dimethyl sulfoxide [DMSO]) will enhance in vitro function and prolong in vivo survival of cryopreserved platelets compared with those preserved in 6% DMSO.
Animals: Thirty-three research dogs.
Methods: Prospective study. Eleven fresh canine apheresis platelet concentrates (PCs) were each split into 3 units: fresh and cryopreserved in 6% DMSO or Thrombosol. Platelet analysis, performed 1–10 weeks postfreezing, included in vitro functional testing and in vivo survival assessed by administration of biotinylated platelets.
Results: Platelet aggregation was diminished in cryopreserved PC. Cryopreserved platelets could be activated, as based on mean thrombin-stimulated P-selectin expression (6% DMSO, 23.0%; Thrombosol, 18.4%), although to a lesser extent than fresh PC (49.1%) ( P < .0001). The mean maximum in vivo platelet recovery for fresh PC was 80.3%, significantly greater than recovery for 6% DMSO (49.2%) and Thrombosol PC (43.7%) ( P ≤ .001). The half-life (days) of fresh PC (3.8 ± 0.4) was significantly ( P < .002) greater than that of 6% DMSO (1.9 ± 1.0) and Thrombosol (2.4 ± 1.1) PC, with no difference ( P = .3) between cryopreserved PC.
Conclusions and Clinical Importance: Cryopreservation of canine platelets using Thrombosol did not provide any advantage over preservation using 6% DMSO. Cryopreserved platelets can be activated in vitro and provide therapeutic benefit when fresh platelets are unavailable. Further studies are needed to assess their in vivo hemostatic function. 相似文献
Hypothesis: The addition of a preparation inhibiting platelet activation (Thrombosol, in 2% dimethyl sulfoxide [DMSO]) will enhance in vitro function and prolong in vivo survival of cryopreserved platelets compared with those preserved in 6% DMSO.
Animals: Thirty-three research dogs.
Methods: Prospective study. Eleven fresh canine apheresis platelet concentrates (PCs) were each split into 3 units: fresh and cryopreserved in 6% DMSO or Thrombosol. Platelet analysis, performed 1–10 weeks postfreezing, included in vitro functional testing and in vivo survival assessed by administration of biotinylated platelets.
Results: Platelet aggregation was diminished in cryopreserved PC. Cryopreserved platelets could be activated, as based on mean thrombin-stimulated P-selectin expression (6% DMSO, 23.0%; Thrombosol, 18.4%), although to a lesser extent than fresh PC (49.1%) ( P < .0001). The mean maximum in vivo platelet recovery for fresh PC was 80.3%, significantly greater than recovery for 6% DMSO (49.2%) and Thrombosol PC (43.7%) ( P ≤ .001). The half-life (days) of fresh PC (3.8 ± 0.4) was significantly ( P < .002) greater than that of 6% DMSO (1.9 ± 1.0) and Thrombosol (2.4 ± 1.1) PC, with no difference ( P = .3) between cryopreserved PC.
Conclusions and Clinical Importance: Cryopreservation of canine platelets using Thrombosol did not provide any advantage over preservation using 6% DMSO. Cryopreserved platelets can be activated in vitro and provide therapeutic benefit when fresh platelets are unavailable. Further studies are needed to assess their in vivo hemostatic function. 相似文献
52.
Diazotized 3-{4-[2-chloro-4-amino-5-carboxybenzyl]-5-chloro-2-carboxyphenyl}-6-iodo-2-phenylquinazolin-4(3H)-one (4) was coupled with various p-nitro anilino cyanurated coupling components (6a-j) to give the corresponding quinazolinone based reactive dyes (7a-j) in reasonable yields. All the reactive dyes (7a-j) were characterized by spectroscopic technique and elemental analysis. These dyes were applied to silk, wool, and cotton
fibers as reactive dyes and their spectroscopic data, colorimetric data, antimicrobial activity, thermal stability, and fastness
properties were evaluated. 相似文献
53.
In Seong Choi Seung Gon Wi Se Ra Jung Darshan H. Patel Hyeun-Jong Bae 《Journal of Wood Science》2009,55(5):329-334
β-Glucosidase (β-1,4-D-glucoside glucohydrolase: EC.3.2.1.21) catalyzes the hydrolysis of β-glucosidic bonds between saccharides
and aryl or alkyl groups. A gene encoding β-glucosidase from Bacillus licheniformis KCTC 1918, an anaerobic spore-forming soil bacterium, was cloned and characterized. The structural gene for the β-glucosidase
consists of 1410 bp encoding 469 amino acid residues, and has a molecular weight of 53.4 kDa as estimated by sodium dodecyl
sulfate polyacrylamide gel electrophoresis with 12% separating gel. The enzyme activity was determined against pNPG as a substrate. The enzyme was optimally active at pH 6.0 (citrate-phosphate buffer) and 47°C. β-Glucosidase retained
100% of its original activity for 24 h. The activity of the enzyme was stimulated by glycerol and urea and was decreased by
Ca2+, Cu2+, Hg2+, Mg2+, and Mn2+. In particular, Cu2+ had the strongest negative effect on β-glucosidase activity. The purified β-glucosidase was active against pNPG and cellobiose. When the β-glucosidase was tested for cellulose hydrolysis, the supplement of β-glucosidase with cellulose
increased the glucose yield from pine wood powder by 139.8%. 相似文献
54.
用10年生丛生竹的节片通过离体腋笋增殖和生根产生出府竹小苗。不同季节对无菌培养物的建立、腋芽发萌和初代培养的影响很大。3片丛生林中,无菌培养物的建立有差别,但腋芽发萌没有差别。用加有31.06uM BA和2.85um IAA的MS液体介质,最大的增值率为3.18;用加有20~25um IBA MS液体介质,离体生根率为66.7~77.8%。用不同的植物生长素,生根所用的天数也不同,而IBA液能在短期促进生根,仅仅为2-3周。成功炼苗后,在装有土壤、沙子和农家肥塑料袋里,离体繁殖的小苗成活率为90%,大约有2000株小苗用于野外栽植。 相似文献
55.
Culture-dependent and culture-independent microbial investigation of pine litters and soil in subtropical Australia 总被引:1,自引:1,他引:0
Background, aim, and scope Forest plantations, widely grown for wood production, involve the selective promotion of single-tree species or replacement
of natural species by exotic tree species. Slash pine (Pinus elliottii) has been chosen for reforestation of infertile sandy soils in southeast Queensland, Australia. These exotic pine plantations
minimize soil and water losses and are important scientific study sites. The soil environment of these plantations, though
devoid of sufficient nutrients, organic carbon and other factors, harbors innumerable bacteria that may play a crucial role
in maintaining soil quality and ecosystem functions. These soil microorganisms also have the potential for use as sensitive
biological indicators to reflect environmental changes. It is therefore essential to understand the interrelationships among
bacterial communities and their environment by assessing their structural and functional diversity and their responses to
disturbances. The main aim of our investigation was to determine the diversity of bacterial communities in forest litters
and soil during the forest leaf litter decomposition using culture-dependent and culture-independent techniques.
Materials and methods A 25-cm (diameter) × 40-cm core sample was collected and fractionated into three subsamples designated E1 (L leaf litter layer),
E2 (F leaf litter layer), and E5 (0–10 cm soil layer). Both culture-dependent and culture-independent methods were applied
in this study. In the culture-independent study, a strategy of whole-community DNA extraction, polymerase chain reaction (PCR)
amplification followed by cloning and 16S rDNA sequence analysis was used; for culture-dependent study, the strategy included
sample plating and bacteria isolating, DNA extraction, PCR amplification, and 16S rDNA sequence analysis. The diversity similarities
between two bacterial communities and two methods are quantified using Jensen–Shannon divergence.
Results From culture-dependent study, 336 colonies in total were isolated and grouped from the three subsamples, and the 16S rRNA
sequence analysis from a representative isolate from each morphogroup (21 isolates) indicated that they belonged to the phyla
Actinobacteria, Firmicutes, and Proteobacteria. Culture-independent assessment based on 16S rRNA gene library comprising 194 clones revealed that members of the phylum Actinobacteria were absent in the culture-independent studies. Clones in libraries from E1 consisted exclusively of members of the Firmicutes. The majority of clones from E2 were related to Firmicutes (79%) and Proteobacteria (21%). Clones derived from E5 were mostly affiliated with Acidobacterium (42%), followed by unclassified bacteria (27%), Verrucomicrobiales (12%), Proteobacteria (11%), and Planctomycetes (8%).
Discussion This study showed that bacterial culturabilities in different fractions of leaf litters were similar, and both of them were
higher than the bacterial culturability in the soil. Unculturable bacterial diversity in the soil, however, was much higher
than the leaf litter bacterial diversity. The bacterial diversity on the top layer of leaf litters was slightly less than
that on the bottom layer of leaf litters. This might indicate that forest soils are a more complex environment than leaf litters
are and also that they might inhabit more unculturable microorganisms in the forest soils, which would need to be further
investigated. The leaf litter layer samples also demonstrate the significant difference between the bacterial community diversity
discovered by these two methods in this study. The information provided by assessing the different fractions of leaf litters
and forest soil has improved our understanding of the bacterial community distributions within the forest soil and the above-leaf
litters in an exotic pine plantation of subtropical Australia.
Conclusions This study represents the first attempt to examine the bacterial community in the different fractions of forest leaf litters
and soil in subtropical Australia. The data from this study show that the 16S rDNA clone libraries provided more comprehensive
phylogenetic diversity in the soil and leaf litter samples than the culture collections provided, and both the culture-dependent
and culture-independent studies revealed that the bacterial diversity present in the leaf litters was very different to that
present in the soil. The comparative analysis of bacterial communities in different fractions of leaf litters and soil samples
has also provided important baseline information about the bacterial diversity and composition in the exotic pine forest plantations.
Recommendations and perspectives The experimental data provided important information on the bacterial diversity in forest leaf litter and soil samples, though
additional surveys and comparisons at different locations would be needed to further characterize. In addition, combined methods
that can provide different parts of information on bacterial diversity are encouraged to be used in bacterial community study.
The established libraries of diverse 16S rRNA gene fragments from slash pine leaf litters and forest soil can be used to construct
specific DNA primers and probes to target bacterial groups of interest. It may then be possible to study the ecology of these
bacterial communities and the role of specific bacterial groups that contribute to the many interesting properties of these
environments. 相似文献
56.
A series of monoazo disperse dyes based on 2-amino-4-phenylthiazole was prepared using variousN,N-dialkylaniline derivatives as the coupling component. The dyes were characterized by IR spectral studies, visible absorption
spectroscopy and elemental analysis. The dyeing performance of these dyes was assessed on cellulose triacetate and nylon fibers.
These dyes were found to give a wide range of colour shades varying from bright red to royal blue with very good depth, brightness
and levelness on fibers. The dyed fibers showed good to very good light fastness and very good to excellent fastness to washing,
perspiration, rubbing and sublimation. The dyebath exhaustion and fixation on the fibers were found to be very good. 相似文献
57.
N. S. Nathawat M. S. Kuhad C. L. Goswami A. L. Patel Rakesh Kumar 《Journal of plant nutrition》2013,36(4):569-598
ABSTRACT The interactions between salinity and different nitrogen (N) sources nitrate (NO3 ?), ammonium (NH4 +), and NO3 ? + NH4 + were investigated on Indian mustard (Brassica juncea cv. RH30). Treatments were added to observe the combined effect of two salinity levels (8 and 12 ds m? 1) and three nitrogen sources (NO3 ?, NH4 +, and NO3 ? + NH4 +) on different growth parameters and mineral composition in different plant parts, i.e., leaves, stem, and root. Salinity has been known to affect the uptake and assimilation of various essential nutrients required for normal growth and development. Different growth parameters, i.e., leaf area, dry weight of different plant parts, absolute growth rate (AGR), relative growth rate (RGR), and net assimilation rate (NAR) declined markedly by salinity at pre-flowering and flowering stages. All growth indices were less sensitive to salinity (12 d s m? 1) with the nitrate form of nitrogen. It is pertinent mention that a high dose (120 kg ha? 1) of nitrogen in ammonium form NH4 +, acted synergistically with salinity in inhibiting growth. Plants fed with combined nitrogen (NO3 ? + NH4 +) had an edge over individual forms in ameliorating the adverse effects of salinity on growth and yield. Under salt stress, different nutrient elements such as N, phosphorus (P), potassium (K+), and magnesium (Mg2 +) were decreased in different plant parts (leaves, stem, and root). The maximum and minimum reduction was observed with ammoniacal and combined form of nitrogen, respectively, while the reverse was true of calcium (Ca2 +), sodium (Na+), chloride (Cl?), and sulfate (SO4 2?) at harvest. Nitrogen application (120 Kg ha? 1) in combined form had been found to maintain highest concentrations of N, P, Mg2 +, and Ca2 + along with reduced concentrations of Na+, Cl?, and SO4 2 ?. However, reverse was true with ammoniacal form of nitrogen. 相似文献
58.
Determination of the physico-chemical characteristics of composite soft wheat flours in which 5–25% (w/w) of the wheat flour was replaced with untreated, roasted and germinated black gram (Phaseolus mungo) flours (BGF) showed that when roasted BGF comprised 20% (w/w) of the blend, the increases in the ash and protein contents were 123% and 35%, respectively. The values for the gluten contents and the Zeleny and sodium dodecyl sulphate sedimentation test volumes for the composite flours indicated a weakening effect of BGF on the quality of soft wheat flour proteins, which could be beneficial for the preparation of biscuits (cookies). The alkaline water retention capacity values increased with the increasing addition of differently processed BGFs. Biscuit baking studies indicated that the diameter and spread ratio of biscuits were reduced, while the thickness increased, with increasing addition of all three BGFs, but the maximum reduction in diameter was observed with the addition of germinated BGF. The hardness value for biscuits increased with the addition of BGFs, but the effect was minimal with roasted BGF and maximal with germinated BGF. The surface grain score was reduced with increasing addition of BGF, but, in general, the roasted BGF showed the minimum adverse effect. From the overall biscuit making quality, addition of untreated BGF at the 15% level and of roasted and germinated BGFs at the 20% level were considered optimal for supplementing wheat flour. 相似文献
59.
V. Gonzalo-Nadal A. Kohl M. Rocchi B. Brennan J. Hughes J. Nichols A. Da Silva Filipe J. I. Dunlop M. Fares J. J. Clark R. Tandavanitj A. H. Patel A. Cloquell-Miro J. Bongers J. Deacon A. Kaczmarska C. Stalin T. Liatis J. Irving R. Gutierrez-Quintana 《The Journal of small animal practice》2024,65(2):132-143
60.
N H Dodman L Shuster M H Court J Patel 《Journal of the American Veterinary Medical Association》1988,192(11):1585-1586
Nalmefene, an opioid antagonist, caused a decrease in self-mutilative behavior in a 500-kg stallion. Self-mutilative attempts were counted during a control period and on 4 subsequent occasions after the IM administration of 100 mg, 200 mg, 400 mg, or 800 mg of nalmefene. The frequency of self-mutilation decreased with increasing doses of nalmefene and was virtually abolished with the 800-mg dose. 相似文献