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91.
There is little evidence concerning the biosynthetic pathways for cyclic diarylheptanoids. We previously demonstrated that the cyclic diarylheptanoids myricanol and myricanone were biologically synthesized from two molecules of 4-coumaric acid by the feeding of 4-[8,9-13C2]coumaric acid to young shoots of Myrica rubra. In the present study, using a 13C-labeled compound, we revealed that two molecules of 3-(4-hydroxyphenyl)propionic acid could also be a biosynthetic precursor of myricanol in M. rubra. These results indicated that both 4-coumaric acid and its dihydro-derivative were incorporated into myricanol. Competitive feeding experiments with 4-[8,9-13C2]coumaric acid and 3-(4-hydroxyphenyl)-[1-13C]propionic acid were performed in M. rubra to determine the preferential incorporation of these two precursors. 13C-NMR studies indicated that 3-(4-hydroxyphenyl)-[1-13C]propionic acid was preferentially incorporated into myricanol. The data provided evidence for a biosynthetic sequence originating from 4-coumaric acid and leading to myricanol, through 3-(4-hydroxyphenyl)propionic acid, in M. rubra.  相似文献   
92.
Using an F1 population from a cross between Japanese pear (Pyrus pyrifolia Nakai) cultivars ‘Akiakari’ and ‘Taihaku’, we performed quantitative trait locus (QTL) analysis of seven fruit traits (harvest time, fruit skin color, flesh firmness, fruit weight, acid content, total soluble solids content, and preharvest fruit drop). The constructed simple sequence repeat-based genetic linkage map of ‘Akiakari’ consisted of 208 loci and spanned 799 cM; that of ‘Taihaku’ consisted of 275 loci and spanned 1039 cM. Out of significant QTLs, two QTLs for harvest time, one for fruit skin color, and one for flesh firmness were stably detected in two successive years. The QTLs for harvest time were located at the bottom of linkage group (LG) Tai3 (nearest marker: BGA35) and at the top of LG Tai15 (nearest markers: PPACS2 and MEST050), in good accordance with results of genome-wide association study. The PPACS2 gene, a member of the ACC synthase gene family, may control harvest time, preharvest fruit drop, and fruit storage potential. One major QTL associated with fruit skin color was identified at the top of LG 8. QTLs identified in this study would be useful for marker-assisted selection in Japanese pear breeding programs.  相似文献   
93.
Progressive ataxia and paralysis in three Miniature Dachshunds were found to be caused by idiopathic sterile pyogranulomatous inflammation of epidural fat between T5 and L4. All dogs were managed by hemilaminectomy and removal of epidural compressive material. Surgical findings and histopathological evaluation were necessary to diagnose epidural pyogranulomatous inflammation. A dog did not regain motor and sensor function after the surgery. Two dogs had exhibited improved neurological function after the surgery, but they recurred. Oral cyclosporine treatment was useful for their long remission. Idiopathic sterile pyogranulomatous inflammation of epidural fat can be considered to be a cause of thoracolumbar myelopathy in dogs.  相似文献   
94.
Platelet-rich plasma (PRP) was administered to cattle with hoof defects (10-mm drill hole) to promote sole defect healing. Two types of gels were prepared. One was a mixed gel [compound of gelatin microspheres (GM) incorporated with PRP and alginate] and was used for the test group, while the other was an alginate gel used for the control group. Each hole was filled with one of these gels. The drill hole depth, pressure pain, and hardness of the regenerated tissue were measured for 3 weeks after treatment. These measurements improved significantly in the test group than in the control group. The results suggest that a compound of GM incorporated with PRP and alginate had a hoof-regenerating effect in cattle.  相似文献   
95.
In peripartum dairy cows, insulin resistance (IR) increases to adjust the direction of energy to lactation after calving. To investigate the effect of prepartum IR on postpartum reproductive performance, the insulin tolerance test (ITT) was applied to 15 cows at 3 weeks (Pre21) and 10 days (Pre10) before the predicted calving date. Blood glucose area under the curve (AUC(glu)) within 120 min after administration of 0.05 IU/kg-BW insulin was calculated. The occurrence of first ovulation, days to first artificial insemination (AI) and first AI conception rate were recorded. Nutritional status postpartum was evaluated by blood chemical analysis. Based on AUC(glu) changes from Pre21 to Pre10, cows were classified into either the AUC-up group (AUC(glu) increase, n=5) or the AUC-down group (AUC(glu) decrease, n=10). There was no difference in the decrease in blood glucose at 30 min after insulin injection between groups, although glucose recovery from 30 to 60 min during the ITT was slow at Pre10 in the AUC-up group. The AUC-up group had a higher number of days to first AI and high glucose, total protein, globulin, γ-glutamyltransferase, triacylglycerol levels and a low albumin-globulin ratio at the 14th day postpartum. The present study infers that prepartum slow glucose recovery rather than insulin sensitivity might increase the potential for subclinical health problems postpartum and thus suppress reproductive performance. During the prepartum transition period, glucose dynamics in the ITT can be considered as a new indicator for the postpartum metabolic status and reproductive performance of dairy cows.  相似文献   
96.
97.
Gametophytic self-incompatibility in Japanese pear (Pyrus pyrifolia Nakai) is controlled by the single, multi-allelic S-locus. Information about the S-genotypes is important for breeding and the selection of pollen donors for fruit production. Rapid and reliable S-genotype identification system is necessary for efficient breeding of new cultivars in Japanese pear. We designed S allele-specific PCR primer pairs for ten previously reported S-RNase alleles (S1S9 and Sk) as simple and reliable method. Specific nucleotide sequences were chosen to design the primers to amplify fragments of only the corresponding S alleles. The developed primer pairs were evaluated by using homozygous S-genotypes (S1/S1S9/S9 and S4sm/S4sm) and 14 major Japanese pear cultivars, and found that S allele-specific primer pairs can identify S-genotypes effectively. The S allele-specific primer pairs developed in this study will be useful for efficient S-genotyping and for marker-assisted selection in Japanese pear breeding programs.  相似文献   
98.
The objective of our study was to compare the characteristics of the corpus luteum (CL) formed after ovulation of the dominant follicle (DF) of the first follicular wave (W1) and those of the CL formed after ovulation of the DF of the second (induced) follicular wave (W2). Non-lactating Holstein cows were used for this study. In Experiment 1, cows were treated with PGF2α and GnRH on days 6 and 8 (day 0 = day of follicular wave emergence) for W1 (n = 6) and W2 (n = 6), respectively. Dominant follicles were aspirated on day 9 to quantify the amounts of mRNA (VEGF120, VEGF164, FGF-2, StAR, P450-scc and 3β-HSD) in granulosa cells (GC). In Experiment 2, the size and blood flow area of the CL formed after ovulation of the DF in W1 (W1CL; n = 6) and W2 (W2CL; n = 6) (the day of DF ovulation in W1 and W2 was day 10) were evaluated on days 12, 15, 18 and 21. The plasma P4 concentration was measured on days 10 to 21. The amounts of VEGF164, P450-scc and 3β-HSD mRNA were higher (P < 0.05) in the DF in W1, and those of VEGF120,FGF-2 and StAR mRNA tended to be higher (P < 0.1) in the DF in W1. The size of the CL was greater in the W1CL on days 15, 18 and 21. The blood flow area of the CL was greater in the W1CL on days 12 and 15. The plasma P4 concentrations were higher in the W1CL. These results indicate that the CL formed after ovulation of the DF in W1 was greater in terms of size, blood flow and plasma P4 concentration.  相似文献   
99.
The infection status of 15 viruses in 120 pigs aged about 6 months was investigated based on tonsil specimens collected from a slaughterhouse. Only 5 species of porcine parvoviruses and porcine circovirus type 2 (PCV2) were detected at high frequencies; 67% for porcine parvovirus (PPV) (PPV-Kr or -NADL2 as the new abbreviation), 58% for PPV2 (CnP-PARV4), 39% for PPV3 (P-PARV4), 33% for PPV4 (PPV4), 55% for PBo-likeV (PBoV7) and 80% for PCV2. A phylogenetic analysis of PPV3 suggested that Japanese PPV3s showed a slight variation, and possibly, there were farms harboring homogeneous or heterogeneous PPV3s. Statistical analyses indicated that the detection of PCV2 was significantly coincidental with each detection of PPV, PPV2 and PPV3, and PPV and PPV4 were also coincidentally detected. The concurrent infection with PCV2 and porcine parvoviruses in the subclinically infected pigs may resemble the infection status of pigs with the clinical manifestations of porcine circovirus associated disease which occurs in 3–5 months old pigs and is thought to be primarily caused by the PCV2 infection.  相似文献   
100.
OBJECTIVE: To evaluate tissue Doppler imaging (TDI) of the left ventricular (LV) free wall (FW) and ventricular septum (VS) as an indicator of LV systolic function in dogs. ANIMALS: 7 healthy Beagles. PROCEDURES: Doses of dobutamine (5 and 10 microg/kg/min) and esmolol (50 and 100 microg/kg/min) were infused into the LV of each dog. With each dose, heart rate; myocardial performance index (MPI); transmitral inflow and ejection time (determined via pulsed-wave Doppler [PWD] echocardiography); and FW and VS velocities of the mitral valve annulus (determined via TDI during systole [S'], early diastole [E'], and late diastole [A']) were assessed. RESULTS: With each dose, dobutamine significantly increased heart rate and the first derivatives of LV pressure (+dP/dt and -dP/dt), whereas esmolol significantly decreased the +dP/dt and -dP/dt values, compared with baseline. Esmolol (100 microg/kg/min) significantly decreased the VS-TDI-derived S' velocity and FW-TDI-derived E' velocity; dobutamine significantly increased transmitral inflow and TDI velocities. Regression coefficient between VS-TDI-derived S' velocity and +dP/dt was higher than that between FW-TDI-derived S' velocity and +dP/dt. Compared with baseline, the PWD- and VS-TDI-derived MPI were significantly decreased by dobutamine and significantly increased by esmolol at each dose. Values of FW-TDI-derived MPI were higher than values derived via the other techniques. Correlation between +dP/dt and VS-TDI-derived MPI was greater than that between +dP/dt and FW-TDI- or PWD-derived MPI. CONCLUSIONS AND CLINICAL RELEVANCE: In healthy dogs, the VS-TDI-derived S' velocity and MPI appear to be reliable assessments for evaluating LV systolic function.  相似文献   
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