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31.
Thlaspi japonicum is a Japanese Ni-hyperaccumulator plant growing in areas with serpentine soil containing a high level of Ni. In the present study, we investigated the ability of wild Thlaspi japonicum plants inhabiting non-ultramafic soil areas of Hokkaido to accumulate Ni/Zn. Wild T. japonicum plants growing on Rebun Island (Rebun-T) accumulated small amounts of Ni, while the plants cultivated on ultramafic rock soil accumulated large amounts of Ni, like T. japonicum growing on Mt. Yubari (Yubari-T), and this change was also observed for T. japonicum growing on Mt. Tengu (Tengu-T). All the T. japonicum plants transplanted on both ultramaflc soil or Andosol accumulated over 100 mg kg−1 Zn, especially the Ni/Zn content of Tengu-T plants tended to be higher than that of the plants growing in the other two areas. In contrast, transplanting of Yubari-T plants from ultramafic soil with a high level of Ni to soil with a lower-Ni content decrease of the Ni concentration in the leaves. Wild Rebun-T plants showed a smaller biomass than the Yubari-T and Tengu-T plants, and some individuals of the Rebun-T population were smaller than those of the other populations, with tiny radical leaves. Zinc content of the small leaves was not significantly different from that in large leaves. These results suggested that T. japonicum plants are able to accumulate high Ni/Zn accumulation, regardless ecotype, habitat and leaf size.  相似文献   
32.
Several studies have indicated that viruses require a specific cytoskeletal structure for replication in host cells. In this study, we examined the role of actin fiber in the replication of canine distemper virus (CDV), belonging to the Morbillivirus genus of the family Paramyxoviridae. For this purpose, we used two actin depolymerizing agents, cytochalasin-D (C-D) and mycalolide-B (ML-B). In Vero cells, C-D disrupted actin fibers distributed in the cytosol, but peripheral actin fibers remained intact. On the other hand, ML-B completely disrupted the actin fibers distributed in both areas. Treatment of Vero cells with C-D or ML-B inhibited the replication of CDV. Double staining of CDV-infected Vero cells with antibody to N-protein and rhodamine-phalloidin revealed the presence of N-protein in mid-cytoplasm. However, the N-protein was specifically localized at the submembrane region in the presence of C-D, whereas it was clustered in the presence of ML-B. Viral mRNA levels of N- and H-proteins were rather increased by treatment with C-D or ML-B. The treatment with ML-B strongly inhibited N-protein expression, whereas C-D only slightly inhibited N-protein expression. These results suggest that actin microfilaments distributed in the cytoplasm and on the membrane region in host cells may have a different role in the process of CDV replication.  相似文献   
33.
The spermatogenic function and plasma testosterone (T) level in the sex maturation process were investigated as to 180 mixed breed cats ranging from 4 months to 2 years in age to be castrated. Testis/epididymis weights reached a peak at 10 and 8 to 9 months of age, respectively. In the testis, sperm appeared at 5 months of age. At 7 months of age, sperm were observed in 96.2% of the cats. In the tail of the epididymis, sperm appeared in 46.9% of the cats at 6 months of age and in all cats at 8 or more months of age. Furthermore, the mean plasma T level rapidly increased at 8 months of age, and reached a peak (2.64 +/- 0.68 (SE) ng/ml) at 10 months of age. Three of 180 cats (1.67%) had unilateral cryptorchidism. These results suggest that the spermatogenic function in male cats becomes mature at 8 to 10 months of age.  相似文献   
34.
Unilateral intrauterine horn insemination (UIUI) was carried out in cats, and we investigated the fertilization rate of ova ovulated from the contralateral ovary. Various numbers of sperm were used to inseminate the uterine horn on the side where ovulation was inhibited. The rates of conception were 1/11 (9.1%), 2/11 (18.2%), and 5/7 (71.4%) in the 2 x 10(6), 4 x 10(6), and 8 x 10 (6) groups, respectively. Furthermore, the fertilization rate was 70.7% in the 8 x 10(6) group. Thus, ova ovulated from the contralateral ovary were not fertilized or the fertilization rate was low in some cats even when UIUI was performed with a large number of sperm.  相似文献   
35.
The aim of this study was to determine whether dobutamine, dopamine, or milrinone (a phosphodiesterase [PDE] III inhibitor) would support cardiac function that had been attenuated by administration of the beta-blocker, carvedilol (0.2, 0.4, or 0.8 mg/kg). Hemodynamic and cardiac parameters including the heart rate (HR), left-ventricular fractional shortening (FS), and arterial pressure were measured in six healthy dogs without cardiac disease. Carvedilol did not affect FS or arterial pressure, but decreased the HR significantly. The positive inotropic and chronotropic responses to dobutamine and dopamine were attenuated by carvedilol, whereas arterial pressure was unaffected. Milrinone did not affect the HR and decreased arterial pressure, whereas FS was significantly greater both in the control and carvedilol-treated groups. Although milrinone affect the negative chronotropic effects of carvedilol, milrinone increased FS and prevented the decrease in arterial pressure. These results suggest that inhibition of PDE III preserves cardiac contractility and hemodynamic function in the presence of carvedilol.  相似文献   
36.
Card15/Nod2 has been suggested to be an intracellular pathogen-associated molecular pattern (PAMPs) recognition molecule, which contains a leucine-rich repeat region similar to the Toll-like receptors (TLRs). Card15/Nod2 gene variants play an important role in the susceptibility to Crohn's disease. In this study, we examined the kinetics of Card15/Nod2 expression in intestinal tissue during inflammation in the 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)-treated rat experimental colitis model. At 2 and 4 days after TNBS administration, the mononuclear cells remarkably infiltrated the mucosal layer and tunica muscularis, which was followed by a gradual decrease to resting levels at 14 days after TNBS administration. Card15/Nod2 mRNA expression increased and peaked at 4 days after the TNBS administration, followed by a gradual decrease in accordance with the amelioration of the inflammatory response. Expressions of Tlr2, Tlr4 and Myd88 were also upregulated in the inflamed colonic region, and in an in situ hybridization study, a positive signal for Card15/Nod2 was observed in the crypt of the epithelial cell layer and in the infiltrated cells of the submucosal and myenteric regions. These results suggest that in addition to the TLR recognition systems, Card15/Nod2 may contribute to the inflammatory process not only in the epithelial and submucosal layers but also in the tunica muscularis.  相似文献   
37.
To identify quantitative trait loci (QTLs) associated with the primary target traits for selection in practical rice breeding programs, backcross inbred lines (BILs) derived from crosses between temperate japonica rice cultivars Nipponbare and Koshihikari were evaluated for 50 agronomic traits at six experimental fields located throughout Japan. Thirty-three of the 50 traits were significantly correlated with heading date. Using a linkage map including 647 single-nucleotide polymorphisms (SNPs), a total of 122 QTLs for 38 traits were mapped on all rice chromosomes except chromosomes 5 and 9. Fifty-eight of the 122 QTLs were detected near the heading date QTLs Hd16 and Hd17 and the remaining 64 QTLs were found in other chromosome regions. QTL analysis of 51 BILs having homozygous for the Koshihikari chromosome segments around Hd16 and Hd17 allowed us to detect 40 QTLs associated with 27 traits; 23 of these QTLs had not been detected in the original analysis. Among the 97 QTLs for the 30 traits measured in multiple environments, the genotype-by-environment interaction was significant for 44 QTLs and not significant for 53 QTLs. These results led us to propose a new selection strategy to improve agronomic performance in temperate japonica rice cultivars.  相似文献   
38.
A 7-year-old, male, mixed breed dog was referred to the Veterinary Teaching Hospital at Kitasato University because of anorexia, lameness and multiple cutaneous lesions. Observation of bone marrow plasmacytosis, osteolytic bone lesions, serum myeloma protein and cutaneous infiltration of myeloma cells led us to a diagnosis of multiple myeloma (MM) with cutaneous involvement. Polymerase chain reaction and sequence analysis for the rearranged genes of immunoglobulin and T-cell receptor demonstrated that the neoplastic cells found in skin lesions or bone marrow are of B-lymphocyte lineage and share a common original precursor cell. The dog was treated with UW-Madison protocol or melphalan/prednisone protocol and survived 175 days. This is rare case of anaplastic MM with cutaneous involvement in dog.  相似文献   
39.
Serial changes in plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) and atrial natriuretic peptide (ANP) concentrations are unknown in dogs with myocardial injury. The time-course secretory responses between NT-proBNP and ANP or cardiac troponin-T (cTnT) related to myocardial infarction (MI) were investigated in this study. Six dogs were anaesthetised and the left anterior descending artery was ligated. A transient decrease in cardiac function was detected 1h after MI but returned to baseline levels within 7 days and remained so for 6 months. Echocardiographic examination revealed focal ventricular dyskinesis throughout the study. Six months following MI, the left atrium to aorta ratio increased significantly although the relative wall thickness decreased significantly from baseline. Significantly elevated plasma NT-proBNP and cTnT concentrations were detected 1 day after MI and these gradually decreased over 28 days to baseline levels without left ventricular pressure elevation. Plasma ANP was elevated significantly 6 months after MI. The NT-proBNP assay is a helpful diagnostic indicator for identifying asymptomatic acute and subacute myocardial injury whereas plasma ANP concentration mainly reflects atrial dilation.  相似文献   
40.
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