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141.
Data of 13'469 blood samples from 10'999 dogs and 2'470 cats tested for rabies neutralizing antibodies within the framework of pet travel schemes were analysed for single and combined factors influencing antibody titres and failures. The time span between vaccination and drawing the blood sample was confirmed as a major source of failure in dogs with a proportion of 23 % at 4 months after primary vaccination (single dose). Failures in dogs and cats (titre < 0.5 IU) were significantly reduced after double primary vaccination (2 doses within 7 - 10 days), although failures reached comparable levels in dogs as early as 6 months after vaccination. In contrast, failure after vaccination was generally below 5 % in dogs and absent in cats after a booster applied at earliest 12 months after single primary vaccination. Statistically significant differences between the failures of the vaccine brands ?Rabisin? (1.5 %), ?Defensor? (6.7 %), ?Nobivac Rabies? (11.0 %) and ?Rabdomun? (18.2 %) were found in dogs but also between the titres induced in cats. Significant differences were found between different dog breeds with some small breeds showing a significantly higher responsiveness. Taken together, a new regimen for rabies vaccination consisting of double primary vaccination with a short interval of 7 - 10 days and a one-year booster appears to be highly recommended for dogs and cats.  相似文献   
142.
The objective of the present study was to establish a method for nuclear replacement in metaphase‐II (M‐II) stage porcine oocytes. Karyoplasts containing M‐II chromosomes (K) and cytoplasts without chromosomes (C) were produced from in vitro‐matured oocytes by a serial centrifugation method. The oocytes were then reconstructed by fusion of one karyoplast with 1, 2, 3 or 4 cytoplasts (K + 1C, K + 2C, K + 3C and K + 4C, respectively). Reconstructed oocytes, karyoplasts without fusion of any cytoplast (K) and zona‐free M‐II oocytes (control) were used for experiments. The rates of female pronucleus formation after parthenogenetic activation in all groups of reconstructed oocytes (58.2–77.4%) were not different from those of the K and control groups (58.2% and 66.0%, respectively). In vitro fertilization was carried out to assay the fertilization ability and subsequent embryonic development of the reconstructed oocytes. The cytoplast : karyoplast ratio did not affect the fertilization status (penetration and male pronuclear formation rates) of the oocytes. A significantly high monospermy rate was found in K oocytes (p < 0.05, 61.6%) compared with the other groups (18.2–32.8%). Blastocyst formation rates increased significantly as the number of the cytoplasts fused with karyoplasts increased (p < 0.05, 0.0–15.3%). The blastocyst rate in the K + 4C group (15.3%) was comparable with that of the control (17.8%). Total cell numbers in both the K + 3C and K + 4C groups (16.0 and 15.3 cells, respectively) were comparable with that of the control (26.2 cells). Our results demonstrate that a serial centrifugation and fusion (Centri‐Fusion) is an effective method for producing M‐II chromosome transferred oocytes with normal fertilization ability and in vitro development. It is suggested that the number of cytoplasts fused with a karyoplast plays a critical role in embryonic development.  相似文献   
143.
Phytochemical investigation of the methanol extract of Tinospora cordifolia aerial parts led to the isolation of four new and seven known compounds. The structures of two new aporphine alkaloids, N-formylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside A, 1) and N-acetylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside B, 2), a new clerodane diterpene, tinoscorside C (3), and a new phenylpropanoid, sinapyl 4-O-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (tinoscorside D, 6) were determined by extensive spectroscopic methods including FTICR-MS and 1D and 2D NMR.  相似文献   
144.
Lignin and cellulose contents and wood basic density were related to diameter at breast height (DBH) in six fast-growing and five slow-growing families from a combined progeny test and seedling seed orchard of Eucalyptus urophylla grown for 10 years in northern Vietnam. The mean cellulose content of the fast-growing families was significantly higher than that of the slow growing-families (40.0 and 37.1%, respectively), and for individual trees cellulose content was significantly correlated phenotypically with DBH. Wood basic density was significantly lower in the fast-growing group than in the slow-growing group (0.506 and 0.535 g cm−3, respectively), and was significantly negatively correlated phenotypically with DBH. The lignin contents were not significantly different between groups. Cellulose content and wood basic density were not correlated. The main conclusion is that there is no obstacle to combining high growth rate with high cellulose content, for plantation of forests intended mainly for pulpwood.  相似文献   
145.
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147.
Dispersion is an important issue for clay leaching in soils. In paddy soils of the Red River Delta (RRD), flooding with fresh water and relatively high leaching rates can accelerate dispersion and the translocation of clay. For the clay fraction of the puddled horizon of a typical paddy soil of the RRD, the effect of various cations and anions as well as humic acid (HA) at different pH values on the surface charge (SC) were quantified and the dispersion properties were determined in test tubes and described by the C50 value. In the <2 µm fraction, dominated by illite, the proportion of 2:1 vs. 1:1 clay minerals is 5:1. The organic‐C content of the clay fraction is 2.2%. Surface charge was found to be highly pH‐dependent. At pH 8 values of –32 and at pH 1 of –8 mmolc kg–1 were obtained. Complete dispersion was observed at pH > 4, where SC is > –18 mmolc kg–1. The flocculation efficiency of Ca strongly depends on the pH. At pH 4, the C50 value is 0.33, 0.66 at pH 5, and 0.90 mmol L–1 at pH 6. At pH 6, close to realistic conditions of paddy soils, the effect of divalent cations on the SC and flocculation decreases in the order: Pb > Cu > Cd > FeII > Zn > Ca > MnII > Mg; FeII was found to have a slightly stronger effect on flocculation than Ca. An increase in concentrations of Ca, MnII, and Mg from 0 to 1 mmol L–1 resulted in a change in SC from –25 to approx. –15 mmolc kg–1. In comparison, the divalent heavy‐metal cations Pb, Cu, Cd, and Zn were found to neutralize the SC more effectively. At a Pb concentration of 1 mmol L–1, the SC is –2 mmolc kg–1. From pH 3 to 5, the dispersion of the clay fraction is facilitated rather by SO than by Cl, which can be explained by the higher affinity of SO to the positively charged sites. With an increase of the amount of HA added, the SC continuously shifts to more negative values, and higher concentrations of cations are needed for flocculation. At pH 3, where flocculation is usually observed, the presence of HA at a concentration of 40 mg L–1 resulted in a dispersion of the clay fraction. While high anion concentrations and the presence of HA counteract flocculation by making the SC more negative, FeII and Ca (C50 at pH 6 = 0.8 and 0.9 mmol L–1, respectively) are the main factors for the flocculation of the clay fraction. For FeII and Ca, the most common cations in soil solution, the C50 values were found to be relatively close together at pH 4, 5, and 6, respectively. Depending on the specific mineralogical composition of the clay fraction, SC is a suitable measure for the determination of dispersion properties and for the development of methods to keep clay particles in the soil in the flocculated state.  相似文献   
148.
The lnbA gene of Lactococcus lactis ssp. lactis IL1403 encodes a polypeptide with similarity to lacto-N-biosidases and N-acetyl-β-D-hexosaminidases. The gene was cloned into the expression vector pET-21d and overexpressed in Escherichia coli BL21* (DE3). The recombinant purified enzyme (LnbA) was a monomer with a molecular weight of approximately 37 kDa. Studies with chromogenic substrates including p-nitrophenyl N-acetyl-β-D-glucosamine (pNP-GlcNAc) and p-nitrophenyl N-acetyl-β-D-galactosamine (pNP-GalNAc) showed that the enzyme had both N-acetyl-β-D-glucosaminidase and N-acetyl-β-D-galactosaminidase activity, thus indicating that the enzyme is an N-acetyl-β-D-hexosaminidase. K(m) and k(cat) for pNP-GlcNAc were 2.56 mM and 26.7 s(-1), respectively, whereas kinetic parameters for pNP-GalNAc could not be determined due to the K(m) being very high (>10 mM). The optimal temperature and pH of the enzyme were 37 °C and 5.5, respectively, for both substrates. The half-life of activity at 37 °C and pH 6.0 was 53 h, but activity was completely abolished after 30 min at 50 °C, meaning that the enzyme has relatively low temperature stability. The enzyme was stable in the pH 5.5-8 range and was unstable at pH below 5.5. Studies with natural substrates showed hydrolytic activity on chito-oligosaccharides but not on colloidal chitin or chitosan. Transglycosylation products were not detected. In all, the data suggest that LnbA's role may be to degrade chito-oligosaccharides that are produced by the previously described chitinolytic system of L. lactis.  相似文献   
149.
Silver nanoparticles (AgNPs) have significantly increased in production and use for anti-microbial propose. This agent, after used, is released into sewerage system resulting in possibility to inactivate non-targeted microorganisms in wastewater treatment plants. In this study, the inhibitory effect of AgNPs on ammonia oxidation was investigated using respirometric assay. The initial concentrations of AgNPs and ammonia ranged 0.25?C10.00 and 14?C280?mg/L, respectively. Half saturation constant (K s) for ammonia oxidation was found to be 15.9?mg?N/L. Under the presence of AgNPs, the maximum oxygen uptake rate and K s declined. The effect of AgNPs was proved to follow an uncompetitive-like inhibition kinetic type with the inhibition coefficients (K i) of 5.5?mg/L. Increasing AgNPs from 0.25 to 10.00?mg/L inhibited 4 to 50?% of ammonia-oxidizing activities at the initial ammonia concentrations from 14 to 280?mg/L. Based on transmission electron microscopic observation, AgNPs could damage the microbial cells. All findings indicated that AgNPs substantially reduced ammonia-oxidizing microorganisms and their activities. Thus, special attention should be made to manage discharge of AgNPs into the environment.  相似文献   
150.
The meal value of Soybean for monogastric animals is determined partly by sucrose, raffinose and stachyose. Of these, sucrose is desirable, while raffinose and stachyose are indigestible, causing flatulence and abdominal discomfort. The objective of this study was to identify quantitative trait loci (QTL) controlling seed sucrose, raffinose, and stachyose in a set of 140 SoyNAM (Nested Association Mapping) recombinant inbred lines (RILs), developed from the cross between lines IA3023 and LD02‐4485. A total of 3,038 SNP markers from the Illumina SoyNAM BeadChip SNP were used to map the QTLs for sucrose and the RFOs, raffinose, and stachyose. Significant genotypic differences (p < .001) among RILs were observed for sucrose, raffinose and stachyose contents across years. A 3038 Illumina SoyNAM BeadChip SNPs identified three QTLs for sucrose, one on chromosome 1, explaining 10% variance and two on chromosome 3 each explaining 22%. Raffinose QTL was detected on chromosome 6, explaining 6% variance. The mapped QTLs were novel and spanned regions harbouring candidate genes with roles in plant growth including seed development.  相似文献   
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