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1.
Chickens contact-exposed to lymphoid leukosis virus at various ages up to 32 weeks responded with relatively high rates of infection as determined by the presence of neutralizing antibody. Virus shedding as determined by cloacal swab and albumen testing occurred in 7 of 8 groups of such chickens, but the incidence was 10% or less and sporadic. Vaccination of chickens immediately before exposure with a low pathogenicity virus of subgroup A at 8 weeks of age did not eliminate subsequent shedding.  相似文献   
2.
Tubulointerstitial nephritis antigen-like 1 (Tinagl1, also known as adrenocortical zonation factor 1 [AZ-1] or lipocalin 7) is a matricellular protein. Previously, we demonstrated that Tinagl1 expression was restricted to extraembryonic regions during the postimplantation period and detected marked expression in mouse Reichert’s membranes. In uteri, Tinagl1 is markedly expressed in the decidual endometrium during the postimplantation period, suggesting that it plays a physical and physiological role in embryo development and/or decidualization of the uterine endometrium during pregnancy. In the present study, in order to determine the role of Tinagl1 during embryonic development and pregnancy, we generated Tinagl1-deficient mice. Although Tinagl1–/– embryos were not lethal during development to term, homologous matings of Tinagl1–/– females and Tinagl1–/– males showed impaired fertility during pregnancy, including failure to carry pregnancy to term and perinatal lethality. To examine ovarian function, ovulation was induced with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); the number of ovulated oocytes did not differ between Tinagl1–/– and Tinagl1flox/flox. In vitro fertilization followed by embryo culture also demonstrated the normal developmental potential of Tinagl1-null embryos during the preimplantation period. Our results demonstrate that Tinagl1 deficiency affects female mice and results in subfertility phenotypes, and they suggest that although the potential of Tinagl1–/– oocytes is normal, Tinagl1 is related to fertility in adult females but is not essential for either fertilization or preimplantation development in vitro.  相似文献   
3.
Abstract

The adsorption of Cr(VI) ion on synthetic hydrated oxides of iron (goethite (α-FeOOH) and lepidocrocite (γ-FeOOH)) with different crystallinities was studied in order to remove the Cr(VI) ion from polluted water. At pH 4.5, the amounts of the adsorbed Cr(V1) ion on goethite and lepidocrocite were 51.9 and 62.2 mmol g?, respectively. Probably, this is due to the fact that the structure of lepidocrocite is more open than that of goethite. Lepidocrocite, therefore, is more effective for the removal of Cr( V1) ion from Cr(Vl)-contaminated and acidic groundwater and sewage.  相似文献   
4.
Cadmium (Cd) is a common impurity in phosphate fertilizers and application of phosphate fertilizer may contribute to soil Cd accumulation. Changes in Cd burdens to agricultural soils and the potential for plant Cd accumulation resulting from fertilizer input were investigated in this study. A field experiment was conducted on Haplaquept to investigate the influence of calcium superphosphate on extractable and total soil Cd and on growth and Cd uptake of different Komatsuna (Brassica rapa L. var. perviridis) cultivars. Four cultivars of Komatsuna were grown on the soil and harvested after 60 days. The superphosphate application increased total soil Cd from 2.51 to 2.75?mg?kg?1, 0.1?mol?L?1 hydrochloric acid (HCl) extractable Cd from 1.48 to 1.55?mg?kg?1, 0.01?mol?L?1 HCl extractable Cd from 0.043 to 0.046?mg?kg?1 and water extractable Cd from 0.0057 to 0.0077?mg?kg?1. Cd input reached 5.68?g?ha–1 at a rate of 240?kg?ha–1 superphosphate fertilizer application. Superphosphate affected dry-matter yield of leaves to different degrees in each cultivar. ‘Nakamachi’ produced the highest yield in 2008 and ‘Hamami No. 2’ in 2009. Compared with the control (no phosphate fertilizer), application of superphosphate at a rate of 240?kg?ha–1 increased the Cd concentration in dry leaves by 0.14?mg?kg?1 in ‘Maruha’, 1.03?mg?kg?1 in ‘Nakamachi’, 0.63?mg?kg?1 in ‘SC8-007’ in 2008, and by 0.19?mg?kg?1 in Maruha’, 0.17?mg?kg?1 in ‘Hamami No. 2’, while it decreased by 0.27?mg?kg?1 in ‘Nakamachi’ in 2009. Field experiments in two years demonstrated that applications of different levels of calcium superphosphate did not influence Cd concentration in soil and Komatsuna significantly. However, there was a significant difference in Cd concentration of fresh and dry Komatsuna leaves among four cultivars in 2008 and 2009. The highest Cd concentration was found in the ‘Nakamachi’ cultivar (2.14?mg?kg?1 in 2008 and 1.91?mg?kg?1 in 2009). The lowest Cd concentration was observed in the ‘Maruha’ cultivar (1.51?mg?kg?1?dry weight (DW)) in 2008 and in the ‘Hamami No. 2’ cultivar (1.56?mg?kg?1?DW) in 2009. A decreasing trend in Cd concentration was found in ‘Nakamachi’, followed by ‘SC8-007’, ‘Hamami No. 2’ and ‘Maruha’ successively. It is necessary to consider a low-uptake cultivar for growing in a Cd polluted soil. In these two years’ results, ‘Maruha’ cultivar was the lowest Cd uptake cultivar compared to the others.  相似文献   
5.
The aim of the present study was to determine the whole nucleotide sequence of the open reading frame of the sex‐determining region Y (SRY‐ORF) in wild sika deer. The SRY gene of wild sika deer was obtained by polymerase chain reaction (PCR) with DNA from blood samples. The whole nucleotide sequence of the SRY‐ORF in wild sika deer consisted of 687 bp and encoded 229 deduced amino acids. In comparison with the bovine SRY gene, the percentage of nucleotide sequence homology was 91.0% in the overall ORF, and those of the N‐terminal, high mobility group (HMG) box, and C‐terminal regions within ORF were 88.9%, 96.2% and 87.9%, respectively. The nucleotide sequences of sika deer SRY‐ORF characterized in the present study can be used for phylogenetic analysis or sexing in wild sika deer.  相似文献   
6.
Japanese larch wood loaded with nickel (1%–4%) alone or with nickel and calcium (0.25%–1.5%) was carbonized at 800°–900°C for 0–120min with a heating rate of 5°–20°C min−1 in a helium flow of 5.8−46.4 ml STP cm−2 min−1 to examine the influence of these variables on the crystallization of carbon (the formation of T component) and the development of mesoporosity. From the obtained results, reaction conditions suitable for effective production of carbon with the dual functions of adequate electroconductivity and adsorption capacity in liquid phase were established, thereby explaining the factors that govern the process. It was also confirmed that mesopore having a diameter of about 4 nm was selectively produced at the cost of specific (BET) surface area in parallel with the formation of T component. This result provided good insight into how the simultaneous dual function could be realized.  相似文献   
7.
8.
Studies that investigate the underlying mechanisms of disease and treatment options typically require the use of a suitable animal model. Few suitable animal models exist for left atrial thrombosis. Here, we demonstrated that the Spontaneously-Running-Tokushima-Shikoku (SPORTS) rat — a Wistar strain known for its running ability—is predisposed to the development of thrombi in the left atrium. We investigated the incidence of left atrial thrombosis in male (n = 16) and female (n = 17) SPORTS rats and observed organized atrial thrombosis in 57% and 38% of males and female rats, respectively. In the male rats, systolic blood pressures and heart rates were significantly higher in SPORTS rats than in control Wistar rats. We could not find any evidence of arrhythmias, such as atrial fibrillation, during electrocardiographic examination of SPORTS rats. We believe that the SPORTS rat could serve as a new research model for left atrial thrombosis; further, it may be suitable for research investigating the development of new antithrombotic approaches for the control of atrial thrombosis or familial thrombophilia in humans.  相似文献   
9.
ABSTRACT:   It is important to clarify trophic dynamics in marine ecosystems for management of the fishing ground. Organic carbon sources and trophic position of pelagic fishes in the coastal waters of the south-eastern Izu Peninsula, Japan, were examined on the basis of carbon and nitrogen stable isotope distributions. The δ13C of the fishes was mostly distributed from −19 to −16‰ for nektonic fishes (13 species of adults and immatures) and planktonic fishes (10 species of larvae and juveniles), close to the δ13C values of particulate organic matter and planktonic decapods. These δ13C signatures for the inhabitants of the water column were in contrast with the high δ13C values (mainly −16 to −13‰) for demersal fishes of Scorpaeniformes and benthic polychaetes collected in the surf zone. These results indicate that nektonic and planktonic fishes depend on phytoplankton for carbon supply. The δ15N signatures suggest that the trophic position ranged 3.1–4.5 for the nektonic fishes and 2.9–3.7 for the planktonic fishes, premised on trophic level 3 for larval Japanese anchovy Engraulis japonicus . Thus, planktivorous fishes should be mainly assigned to trophic levels 3 and 4 in this area.  相似文献   
10.
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