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101.
Midgut juice of Plutellaxylostella strain PXR which is resistant to Cry1Ac was biochemically characterized relative to the susceptible PXS strain. The midgut juice of PXR (PXR-Juice) was shown to process Cry1Ac protoxin to 60 kDa active toxin with the same processing pattern as that of juice from PXS (PXS-Juice) in SDS–PAGE. PXS larvae which were given the Cry1Ac toxin pre-processed with PXR-Juice were killed with the same rate as that with Cry1Ac pre-activated by trypsin. PXR-Juice was found to contain three times larger amount of 66 kDa protein (P66) than PXS-Juice and the N-terminal amino acid sequence of P66 was matched to that of glucosinolate sulfatase in data base search. The protein band of P66 was coincided with the band of p-nitro phenyl sulfatase activity in zymogram. P66 purified to homogeneity in SDS-PAGE bound to Cry1Ac and soybean agglutinin, and KD for Cry1Ac was estimated to be 718 nM with surface plasmon resonance analysis. Using purified sulfatase, Km and Vmax were estimated and involvement of the enzyme in the PXR resistance was discussed.  相似文献   
102.
103.
Atlanto-occipital fusion in a Japanese Brown calf was examined morphologically, paying special attention to skeletal changes. At the craniovertebral junction, the basal occipital bone fused to the cranial extremity of the ventral arch of the atlas with the rudiment of the atlantal centrum. The dens was not formed at the axis. These changes suggest that a hypocentrum and a centrum of the atlas derived from the first cervical sclerotome had failed to separate the occipital base from the proatlantal sclerotome including the apical element of the dens. Although a developmental disturbance at the cervical and thoracic vertebrae was also associated, critical neurological signs such as ataxia and paralysis were absent.  相似文献   
104.
Laboratory and field tests were conducted to evaluate the immunogenicity of a live-virus vaccine against infectious laryngotracheitis (ILT) of chickens that was prepared using tissue-culture-modified strain C7. Eighty-three percent or more of chickens vaccinated by the ocular (OC) or intranasal (IN) route with 10(4.75) TCID50 of the attenuated strain C7 at 50 days of age were protected against challenge with a virulent strain of ILT virus without showing any clinical signs for 4 weeks post-vaccination (PV). When vaccine was administered by aerosol, however, only 65% of vaccinated chickens were protected against challenge. Fifty-seven percent of chickens vaccinated at 70 days of age maintained immunity for 6 months PV. Immune response in younger chickens was inferior to that in older ones. In the field trials, clinical observation revealed no adverse reactions caused by the vaccination, and 60% or more of broilers and 80% or more of layers vaccinated by the OC route were protected against challenge at 4 weeks PV. These results confirmed the safety and efficacy of the vaccine.  相似文献   
105.
A pad equivalent for a dog was prepared as a substitute for the loss of footpad. In addition to the time course of formation on epidermal morphogenesis, we investigated expressions of alpha(6) integrin subunit as adhesive molecule, and laminin and type IV and VII collagens as extracellular matrices of basement membrane components. Epithelium of the pad equivalent was thick enough to be easily confirmed at 5 days at the air-liquid interface, but many creases appeared on it at 7 days, and it shrank at 10 and 14 days. Keratinocytes were increased in 4 to 5 cell layers at 1 day at the air-liquid interface, differentiating into basal cell layer. Granular and corneal cell layers were confirmed until 5 days, and maintained their shape at least until 14 days. Alpha 6 integrin was expressed at almost the same fluorescent intensity as native pad tissue at 1 day at the dermal-epidermal junction. Laminin and type IV collagen were intermittently expressed at 5 and 10 days, respectively, at the dermal-epidermal junction, and at 14 days the fluorescence showed almost the same intensity as native pad tissue. The expression of type VII collagen was discontinuous at 2 days at the dermal-epidermal junction, but remained as it was at 14 days. The present findings suggested that although the formation of anchoring fibrils in basement membrane was incomplete, the pad equivalent in the dog was reconstructed similar to a native pad by epidermal morphogenesis.  相似文献   
106.
In excretory urography, the osmolarity of contrast media has rarely been treated as important in veterinary medicine. In this study, the contrast effect of two contrast media (monomeric iohexol and dimeric iodixanol) in the renal cortex and aorta were compared using computed tomography (CT). Five beagle dogs were used and the study employed a cross-over method for each contrast media. The results showed that there was no difference between the media in the aorta, but iodixanol showed higher CT value and a longer contrast effect than iohexol in the renal cortex, in spite of having the same iodine dosage. It is believed that iodixanol, with its low osmolarity, is diluted less by osmotic diuresis than monomeric iohexol. It is important to consider the osmolarity of the contrast media when evaluating the contrast effect, and it is essential to use the same contrast media for each examination, or the renal excretory speed will be under/overestimated.  相似文献   
107.
Cell-to-cell interaction via cell contact-dependent pathway is essentially important for maintenance and regulation of corpus luteum (CL) integrity and its physiological actions. The objective of the present study was to evaluate the mRNA expression of the cell adhesion molecules (CAMs) that are constituent factors of gap junctions [connexin (Cx) 43] and adherence junctions (VE-, E-, N-cadherin) in two types of endothelial cells from the mid CL and in CL tissue during the estrous cycle and PGF(2alpha)-induced luteolysis in the cow. Specific mRNA expression for Cx43 and N-cadherin was detected in cytokeratin-positive (CK+) and cytokeratin-negative (CK-) luteal endothelial cells (EC) and fully luteinized granulosa cells (LGC). E-cadherin mRNA was expressed in CK+EC and LGC, but not in CK-EC. VE-cadherin mRNA was expressed in both CK+ and CK-EC. During the estrous cycle, Cx43 mRNA expression was significantly lower in the regressing CL. VE-cadherin expression also tended to increase in the mid CL and increased significantly in the regressing CL. E-cadherin mRNA expression was higher in the early and late CL than in the mid- and regressing CL. N-cadherin mRNA expression gradually increased from the early to late CL followed by a decrease in the regressing CL. During PGF(2alpha)-induced luteolysis, Cx43 mRNA expression appeared to increase, and VE-cadherin and E-cadherin mRNA significantly increased at 24 h. N-cadherin mRNA expression decreased 2 and 4 h after PGF(2alpha) administration. Collectively, expression of the mRNAs for CAMs was different in the two types of luteal endothelial cells and fully luteinized granulosa cells and changed independently in the CL during the estrous cycle and PGF(2alpha)-induced luteolysis in the cow. The results suggest that CAMs play physiological roles in cell-to-cell communication to regulate both gap and adherence junctions during CL development and regression in the cow.  相似文献   
108.
The aims of this study were 1) to determine whether dairy cows can be induced to ovulate by the treatment with gonadotropin releasing hormone (GnRH) followed by prostaglandin F(2 alpha) (PGF(2 alpha)) during the early postpartum period and 2) to describe their ovarian and hormonal responses according to ovarian status. Cows were divided in two groups and received 10 microg of buserelin followed by 500 microg of cloprostenol 7 days apart starting from 21 (GnRH21, n=7) or around 37 days postpartum (GnRH37, n=7). The groups were further classified according to presence (-CL) or absence (-NCL) of functional corpora lutea (CL) on the day of GnRH treatment (d 0): GnRH21-NCL (n=4), GnRH21-CL (n=3) and GnRH37-CL (n=7). Ovarian morphology was monitored and the concentrations of P(4), E(2), FSH and insulin-like growth factor 1 (IGF-1) were measured. All cows ovulated after administration of GnRH. The P(4) levels of the GnRH21-NCL group from d 0 to d 5 were lower than those of the GnRH21-CL (P<0.05) and GnRH37-CL groups (P<0.01). In contrast, the E(2) levels of the GnRH21-NCL group within d 2 to d 6 were higher (P<0.05) than those of the other groups. Compared with the GnRH37-CL group, the GnRH21-NCL group had more small follicles on d 2 (P<0.05), d 3 (P<0.01) and d 4 (P<0.01) and more large follicles on d 5 (P<0.05). The induced CL and new ovulatory follicles were larger in the GnRH21-NCL group compared with the GnRH21-CL (P<0.001 and P<0.01) and GnRH37-CL groups (P<0.001 and P<0.05). IGF-1 did not differ among the groups. The GnRH21-NCL group had higher FSH levels than the GnRH21-CL (P<0.01) and GnRH37-CL groups (P<0.001) on d 0. Low P(4) and high FSH levels may suggest higher gonadotropin support on the enhanced ovarian morphology of the GnRH21-NCL group. PGF(2 alpha) treatment induced CL regression and subsequent ovulation in 3/4 (75%), 3/3 (100%) and 7/7 (100%) cows in the GnRH21-NCL, GnRH21-CL and GnRH37-CL groups, respectively. In conclusion, a 7-day GnRH-PGF(2 alpha) synchronization protocol can effectively induce dairy cows to ovulate as early as 21 days postpartum, regardless of ovarian status.  相似文献   
109.
The stem productivity of the hinoki cypress (Chamaecyparis obtusa Endlicher) in relation to plant nitrogen status and water-use efficiency was investigated in the Okuono (OKU) and Karakawa (KRK) areas in Shikoku district, Japan, where abundant precipitation occurs. The nitrogen concentration and carbon isotopic composition (δ13C) in the leaves were used as indexes of plant nitrogen status and water-use efficiency, respectively. The leaf nitrogen concentration increased with decreasing soil carbon/nitrogen (C/N) ratio and with increasing soil pH. There was a marginally significant negative correlation between leaf δ13C and soil water content in the KRK area, but leaf δ13C in the OKU area did not correlate with the soil water condition, and increased on the upper slope. The results suggest that hinoki trees in the KRK area have higher water-use efficiency (high leaf δ13C) under lower soil water conditions. In the OKU area, meanwhile, leaf δ13C in the upper slope was higher due to adaptation to adverse conditions. When 12 plots in two areas were included, the mean height and stem increments increased with increasing leaf nitrogen concentration and with decreasing leaf δ13C. These findings suggest that nitrogen acquisition is a primary factor for stem productivity in the areas concerned but the productivity of some forests is restricted by the soil water condition or other conditions, as indicated by the high value of leaf δ13C. The measurement of nitrogen concentration and δ13C in leaves can provide us with valuable insights into the relative importance of nitrogen, water and other conditions on stem productivity in the two areas.  相似文献   
110.
Sodium (Na) application has marked beneficial effects on plant growth when the potassium (K) supply is low. Under low K supply, three japonica rice (Oryza sativa L.) cultivars, Koshihikari, Nipponbare, and Sasanishiki, accumulated more Na than three indica cultivars, IR36, IR64, and Kasalath, and the effect of Na application on growth was greater in japonica Koshihikari plants than in indica IR64 plants. A quantitative trait locus (QTL) analysis using a population of backcross inbred lines derived from japonica Koshihikari and indica Kasalath identified two significant loci associated with shoot Na concentration on chromosomes 3 and 6. The quantitative trait locus for shoot Na accumulation on chromosome 6 was confirmed in a population of chromosome segment substitution lines. The major QTL detected in this study could be useful for increasing crop productivity under low K input.  相似文献   
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