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81.
82.
(Jpn. J. Soil Sci.Plant Nutr., 77, 293–298, 2006)
"Kitanokaori" is a new variety of wheat for bread use bred at the National Agricultural Research Center for Hokkaido Region. The grain protein content of wheat for bread use should be higher than 120 g kg−1. Much nitrogen application is necessary to obtain high grain protein content. Therefore, it is necessary to determine the optimum amount of nitrogen to obtain the required protein content and to prevent nitrogen from remaining in the soil. The nutrition diagnosis using leaf color was investigated to predict the need and the amount of top-dressing. Field experiments were conducted for four years with nitrogen treatments in Andosol, which has moderate nitrogen fertility, and in Histosol, which is a fertile soil. The leaf color was measured using a chlorophyll meter SPAD502 (CM value) at the middle part of the leaf, avoiding the center rib. The colors of the 10·15 uppermost second leaves were measured in one plot and averaged.
A close relation was found between leaf color at the full heading stage and grain protein content at harvest. Leaf color at the full heading stage is therefore a good index to control the protein content. Considering the effect of top-dressing at the full heading stage in each CM value, the diagnosis criterion was decided. When the CM value is over 52 at the full heading stage, more nitrogen application is not needed. When the CM value is 50·52, 30 kg N ha−1 of top-dressing at the full heading stage is needed, and when the CM value is 45·50, 60 kg N ha−1 of top-dressing is needed to obtain a grain protein content of more than 120 g kg−1.  相似文献   
83.
84.
Jiro  KOYAMA  Akira  KAKUNO 《Fisheries Science》2004,70(4):587-594
ABSTRACT:   This study examines the toxicity of three dispersants and heavy fuel oil to a marine fish, red sea bream ( Pagrus major ). Also studied was the toxicity of a mixture of heavy fuel oil and the least toxic of the three dispersants. The 24-h LC50 of all three dispersants were at least 1500 mg/L; these dispersants appeared relatively less toxic to marine fish than others studied in the past. The mean lethal oil concentration of the water-accommodated oil fraction was 325 µg/L. Mixtures of oil and dispersant were more toxic than dispersant or oil alone. Large amounts of dispersant decreased the toxicity of the mixture for the marine fish. Use of a dispersant-to-oil percentage of 20%, which is recommended by the manufacturer because of its efficiency in oil emulsification and dispersion, yielded higher 24-h oil concentrations and resulted in a higher mortality rate than did the use of higher percentages of dispersant. The application of dispersant to oil in coastal areas, especially with higher activities of fisheries and aquaculture like Japan, must be considered carefully in the context of the benefits versus environmental cost.  相似文献   
85.
Pneumotropic virus invasion of parenchymal organs in mice with immunosuppressants is worth studying from an etiopathogenetic viewpoint as an animal model of a compromised host. This study analyzed the invasion by Sendai virus (SeV) of mouse organs in immunosuppressive states induced by cortisone (CO) and cyclophosphamide (CY). After subcutaneous inoculation of CO or CY, or both, in mice infected intra-nasally with SeV, the SeV invasion was investigated by detecting viremia and viral antigen in organs. SeV Nagoya strain and one treatment of CO or CY caused viremia at 18 hr or 3 d, respectively, with infection in tracheal lymph nodes, but not in untreated mice. SeV invaded hepatocytes and splenolymphocytes on days 10 and 5-10, respectively, after infection. CO or CY treatment, three times, induced viral invasion of brain tissues or serious respiratory infection, respectively, but progressive invasion of abdominal parenchymal organs was not different between treated groups. One CO and two CY treatments intensified viral invasion into many organs, maintaining seronegativity. Cerebral blood vessels had the highest incidence of viral antigen in the brain. Astroglial sheets, choroid plexuses, pia maters, and ventricular epithelia tested positive; test-positive neurons were few. SeV MN strain caused progressive invasion of the brain with gliosis and neuronophagy. Blood-brain barrier disruption was caused by virulence of the MN strain. Half the infected mice in two groups treated with CO once and CY twice succumbed to delayed hypersensitivity, suggested by cerebro-microvascular nodulation.  相似文献   
86.
A nine-year-old, male, mongrel dog was unsteady after falling down a set of stairs. The dog exhibited a mildly abnormal gait 2 days after injury, and was not able to stand, with spasticity of the right limbs, 4 days after injury. MR imaging revealed a clearly demarcated mass on the top of the left lateral ventricle that showed mild hyperintensity on T1-weighted images and hyperintensity on T2-weighted images. The authors diagnosed the dog as having a traumatic intracerebral hematoma. This type of case, in which the clinical signs deteriorated due to edema associated with hematoma, is extremely rare.  相似文献   
87.
This study describes a chemotaxis assay of ferret polymorphonuclear cells (PMNs). The optimal conditions for this chemotaxis assay were investigated for three chemoattractants: zymosan activated serum (ZAS), recombinant human interleukin-8 (rhIL-8) and N-formyl-Met-Leu- Phe (fMLF). In this study, ferret polymorphonuclear cells (PMNs) reacted to ZAS and rhIL-8, but not fMLF. The optimal concentration of ZAS and rhIL-8 were 5% and 100 ng/ml, respectively. The optimal incubation time of each reagent was 60 min. Due to the lack of response shown from fMLF, the existence of formyl peptide receptors (FPR) on ferret PMNs was investigated by evaluating FPR binding using flow cytometry. The receptor was not detected, implying that ferret neutrophils may lack FPR. This study confirms the fundamental experimental conditions for ferret PMNs chemotaxis and elucidates new findings concerning FPR in ferret neutrophils.  相似文献   
88.
To investigate the early host defense function in aquatic animals, the respiratory burst activity of bottlenose dolphin neutrophils against soluble and particulate stimulants was measured by luminol-dependent chemiluminescence assays and compared with those of bovine and human. Dolphin neutrophils generated the respiratory burst in response to phorbol 12-myristate 13-acetate (PMA), concanavalinA (ConA), heated-plasma (HP), and homologous-plasma opsonized zymosan except N-formyl-Met-Leu-Phe (fMLP). However, the respiratory burst of dolphin neutrophils stimulated by lipopolysaccharide and Staphylococcus aureus was inferior to those of bovine and human. Furthermore, DP-OZ also induced the respiratory burst of bovine and human neutrophils. In conclusion, dolphin neutrophils responded to several soluble and particulate stimulants as well as human neutrophils, but were refractory or slightly responded to bacterial agents.  相似文献   
89.
Manganese deficiency results in neurological and skeletal defects, together with ultrastructural disarrangement of the retina in rats. Wild birds show a range of Mn concentrations in their tissues, including the liver, raising the possibility of Mn-related disorders in the wild. Electroretinography (ERG) provides a useful noninvasive approach to evaluate visual function. This method is especially useful in birds, as objective analysis of them is very difficult, while they have well-developed vision. In this study, we carried out a convenient and reliable ERG recording using a contact lens electrode with a built-in light source (LED electrode) of Japanese quail (Coturnix coturnix japonica) fed a Mn-deficient diet. After 10 min light adaptation, single-flash and flicker cone responses were reproducibly recorded to cause an intensity-dependent increase in amplitude of both a-wave and b-wave in single-flash ERG. Mn-deficient feeding markedly decreased the Mn concentration in the liver by almost half in 3 to 6 weeks, followed by body weight loss in 13 to 15 weeks. Implicit time of a-wave and b-wave cone response by single-flash stimulation was significantly delayed in quail with a Mn depletion from 3 to 6 weeks. Every cone response of the Mn-deprived quail had a tendency to decrease amplitude. The ultrastructure of cone photoreceptor cells was disorganized by Mn deficiency, including changes in outer segment discs of photoreceptor cells. These results suggest the essential role of Mn in the integrity of the retinal function of birds.  相似文献   
90.
The aim of this study was to classify the histopathological features of pigs infected with Mycobacterium avium complex (MAC). We used slaughtered pig organs systemically infected with MAC. The results showed granulomatous lesions which were observed predominantly in the digestive organs and regional lymph nodes rather than respiratory organs. The histological picture showed a wide range of granulomatous stages from exudative to fibrotic reactions to the MAC infection. Eosinophils and giant cells were characteristically observed in the exudative reactions. The histopathological type in primary focus tended to be maintained in the respective organs. Most strains with the same genotype showed pathogenicity for guinea pigs irrespective of the type of granuloma. Although these findings suggest that different stages of a granulomatous lesion originating from the same causative agent might influence histological patterns, other possibilities such as the hereditary background of the host, or the effects of viral infections should be considered.  相似文献   
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