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1.
Due to the potential for anti-erythrocyte membrane antibodies as possible enhancers of erythrocyte destruction, the presence of serum anti-erythrocyte membrane antibodies in 31 dogs with Babesia gibsoni infection admitted to a veterinary hospital was investigated by an enzyme linked immunosorbent assay (ELISA) and immunoblotting analyses. This infection resulted in an increase of anti-erythrocyte membrane antibodies in 84% (IgG) and 74% (IgM) of 31 infected dogs, respectively. This was confirmed by the similarity in the protein profiles of the erythrocyte membrane antigens immunoblotted with rabbit antiserum to dog erythrocyte membrane antigens and infected dog serum. These results suggest the production of anti-erythrocyte membrane antibodies was induced by B. gibsoni infection.  相似文献   
2.
The present study was conducted to examine the effects of three tannin relatives (tannic acid, TA; gallic acid, GA; and ellagic acid, EA) on antihyaluronidase and reactive oxygen species (ROS) scavenging activity, in vitro fertilization (IVF) parameters, and the acrosome reaction (AR) induced by sperm-zona interaction. Among the three tannin relatives, TA and EA showed the strongest potency for blocking the hyaluronidase activity of boar sperm, with concentration-dependent inhibition over the range of 2-10 microg/ml. In contrast, ROSs were effectively scavenged by TA and GA, but not EA. When cumulus-free oocytes were inseminated in IVF medium containing 5 microg/ml of the tannin relatives, polyspermy was significantly reduced by TA and EA (32 and 29%, respectively) compared with oocytes treated with or without GA (51 and 69%, respectively) under conditions that maintained a high sperm penetration rate (P<0.05). Interestingly, induction of the AR by treatment of preincubated sperm with progesterone was blocked by TA and GA as a result of their higher levels of ROS scavenging activity, while EA, which possessed weak ROS scavenging activity, did not disturb induction of the AR with progesterone. However, the incidence of AR induced by sperm-zona interaction was significantly decreased by the strong antihyaluronidase actions of TA and EA compared with that in the absence of these compounds. Treatment with the compounds caused neither a protective proteolytic modification of the zona pellucida matrix before fertilization nor a reduction in acrosomal proteolytic activity or the number of zona-bound sperm. These findings suggest that the antihyaluronidase action of EA effectively prevents polyspermy by suppression of AR functionality induced by sperm-zona interaction and that hyaluronidase intervention is therefore required during porcine IVF.  相似文献   
3.
A free-ranging California condor (Gymnogyps californianus) presented severely dehydrated, unable to stand, very weak, and with a distended crop. Toxicologic analysis revealed an elevated blood lead level of 291.4 microg/ ml. There was no evidence of lead exposure on radiographs. The condor was treated with chelating agents and intensive supportive care. Over a period of 10 days, a majority of its clinical signs improved, and lead levels dropped to near normal. However, the condor was left with a severe, persistent crop stasis and malnutrition. An esophagostomy tube, and later an ingluviostomy tube, were placed and maintained for a period of 1 mo. The condor was managed with continuous infusion feeding. After the feeding tube was removed, the condor was managed with small amounts of soft food orally. After 10 wk of treatment, the crop returned to normal function.  相似文献   
4.
Agrobacterium-mediated transformation for both Melastoma malabathricum and Tibouchina semidecandra were optimized using green fluorescent protein (GFP) as a reporter. The binary vector pCAMBIA1304 harboring the modified green fluorescent protein (mgfp) gene driven by the CaMV 35S promoter was used. Parameters optimized were bacterial strain, bacterial concentration, pre-culture period, co-cultivation period, immersion time, acetosyringone concentration and wounding type. Results obtained were based on the percentage of GFP expression which was observed 3 days post-transformation. Agrobacterium tumefaciens strain LBA4404 and EHA105 at concentration 1 × 107 cfu ml−1 (OD600nm 0.8) showed the highest virulence on M. malabathricum and T. semidecandra, respectively. Four days of pre-culture and 2 days of co-cultivation were optimum for M. malabathricum transformation, while 3 days of pre-culture and co-cultivation for T. semidecandra. Result also showed that 60 min of immersion and addition of 200 μM acetosyringone gave the highest percentage of positive transformants for both M. malabathricum and T. semidecandra. Mild wounding also significantly increased the efficiency of M. malabathricum transformation.  相似文献   
5.
The objective of this paper is to investigate potential use of a spatially constrained harvest scheduling model for biodiversity concerns. Change in the degree of biodiversity is represented only by spatial characteristics of harvesting patterns of forest stands with different exclusion periods applied to adjacent forest stands. A spatially constrained harvest scheduling model called SSMART (Scheduling System of Management Alternatives foR Timber-harvest) is used for the analysis. It is one of the heuristics to solve a spatially constrained harvest scheduling problem by using the partitioning heuristic. The algorithm incorporated into SSMART is designed to seek a solution for a multicriteria problem with present net value maximum, meeting spatial feasibility and minimizing period-to-period harvest flow fluctuation, approximating even-flow constraints within the 0–1 integer programming framework. Our experimental analysis shows that the longer exclusion period, the less the harvest flow level and the total present net value are derived and the more heterogeneous the forest structure becomes in terms of the forest stand age distribution. It is also shown that the three exclusion period results in a stable forest stand age distribution over the time horizon for our experimental forest. This research supported by the Grants-in-Aid for Scientific Research (No. 09041071) from the Ministry of Education, Science, Sports, and Culture of Japan.  相似文献   
6.
Papaya seed represents a rich source of biologically active isothiocyanate   总被引:1,自引:0,他引:1  
In the present study, papaya (Carica papaya) seed and edible pulp were carefully separated and then the contents of benzyl isothiocyanate and the corresponding glucosinolate (benzyl glucosinolate, glucotropaeolin) quantified in each part. The papaya seed with myrosinase inactivation contained >1 mmol of benzyl glucosinolate in 100 g of fresh seed. This content is equivalent to that of Karami daikon (the hottest Japanese white radish) or that of cress. The papaya seed extract also showed a very high activity of myrosinase and, without myrosinase inactivation, produced 460 micromol of benzyl isothiocyanate in 100 g of seed. In contrast, papaya pulp contained an undetectable amount of benzyl glucosinolate and showed no significant myrosinase activity. The n-hexane extract of the papaya seed homogenate was highly effective in inhibiting superoxide generation and apoptosis induction in HL-60 cells, the activities of which are comparable to those of authentic benzyl isothiocyanate.  相似文献   
7.
The main energy sources of soil microorganisms are litter fall, root litter and exudation. The amount on these carbon inputs vary according to basal area of the forest stand. We hypothesized that soil microbes utilizing these soil carbon sources relate to the basal area of trees. We measured the amount of soil microbial biomass, soil respiration and microbial community structure as determined by phospholipid fatty acid (PLFA) profiles in the humus layer (FH) of an even-aged stand of Scots pine (Pinus sylvestris L.) with four different basal area levels ranging from 19.9 m2 ha−1 in the study plot Kasper 1 to 35.7 m2 ha−1 in Kasper 4. Increasing trend in basal respiration, total PLFAs and fungal-to-bacterial ratio was observed from Kasper 1 to Kasper 3 (basal area 29.2 m2 ha−1). The soil microbial community structure in Kasper 3 differed from that of the other study plots.  相似文献   
8.
Trials over two years were conducted using 1389 sweetpotato (Ipomoea batatas L.) genotypes collected from all over the world to characterize the polyphenolic composition in sweetpotato leaves. Wide variation was observed in relation to their total and individual leaf polyphenolic constituents. In all genotypes studied, the total polyphenol contents of sweetpotato leaf ranged from 1.42 to 17.1 g/100 g dry weight. The six different polyphenolic compounds were identified and quantified by NMR, FABMS, and RPHPLC analysis procedures. This is the first report of polyphenolic compositions in sweetpotato leaves. The relative levels of polyphenolic acids in sweetpotato leaves were as follows: 3,5-di-O-caffeoylquinic acid > 4,5-di-O-caffeoylquinic acid > chlorogenic acid (3-O-caffeoylquinic acid) > 3,4-di-O-caffeoylquinic acid > 3,4,5-tri-O-caffeoylquinic acid > caffeic acid. The highest 3,4,5-tri-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid occurred at 221 and 1183.30 mg/100 g dry weight, respectively.  相似文献   
9.
Shorter-wavelength surface-emitting laser sources are important for a variety of fields, including photonics, information processing, and biology. We report on the creation of a current-driven blue-violet photonic-crystal surface-emitting laser. We have developed a fabrication method, named "air holes retained over growth," in order to construct a two-dimensional gallium nitride (GaN)/air photonic-crystal structure. The resulting periodic structure has a photonic-crystal band-edge effect sufficient for the successful operation of a current-injection surface-emitting laser. This represents an important step in the development of laser sources that could be focused to a size much less than the wavelength and be integrated two-dimensionally at such short wavelengths.  相似文献   
10.
根癌农杆菌介导的叶用莴苣基因转化系统的建立   总被引:2,自引:0,他引:2  
以叶用莴苣微茎尖为试材,在含有BA和NAA的MS液体培养基上旋转培养,诱导出大量愈伤组织;进一步分化培养,获得大量不定芽并生根;将愈伤组织碎块与根癌农杆菌共培养,对经卡那霉素筛选后所得到的再生植株进行X-Gluc染色,蓝色反应阳性率为80%,表明建立了叶用莴苣愈伤组织基因转化系统。  相似文献   
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