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1.
Canine cationic trypsin was purified by salting-out, gel filtration and affinity chromatography. Purity was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight was ca. 28 kDa by SDS-PAGE.

Thirty hybridomas were obtained which produced mAb to canine cationic trypsin by the cell fusion technique. Twenty-two of these recognized cationic trypsin only, while eight hybridomas recognized both cationic and anionic trypsin. Several of the anti-canine cationic trypsin mAb were purified by salting-out and DEAE ion-change chromatography using ascites fluid of immunized BALB/c mice. The mAb proved to have very high specificity to canine cationic trypsin as shown by immunoblotting and it may be possible to use them to develop clinical assays.  相似文献   

2.
Cadmium levels were determined in rice grains of Japonica, Indica, Javanica, and Indica-Japonica hybrid-bred varieties that were produced in the same plot of a non-polluted field in 1983 and 1985, using nameless atomic absorption spectrophotometry.

Cadmium levels in the brown rice grains harvested in 1983 and 1985 ranged from 2.1 to 27 0 ppb Cd for 28 Japonica varieties, 4.1 to 55.5 for 23 Indica varieties, 4.4 to 16.5 for 5 Javanica varieties, and 24.5 to 73.6 for 4 hybrid varieties.

The significant correlation of the cadmium levels between the 1983 and 1985 products may indicate the possible occurrence of varietal differences in the natural abundance of cadmium in rice grains. There was no correlation between the cadmium levels and the duration of ripening in each variety, suggesting that these differences could be partly attributed to some physiological characteristics of the rice varieties.  相似文献   
3.
Nitrogen nutrition has great influences not only on the yields, but also on the chemical components of the plants. Nitrate nitrogen is generally found to be superior to ammonium nitrogen as the nitrogen source for higher plants (1). As reported in the previous paper (2), young plants of sugar beet grown with the culture solution containing a high level of ammonium nitrogen developed the symptom of ammonia toxicity. To make clear the mechanism of ammonia toxicity, comparative studies on the absorption and the assimilation of ammonium- and nitrate-nitrogen in higher plants at young stages of growth were carried out.  相似文献   
4.
A female congenic rat produced by repeated backcrossing of Nihon rats, a model for hereditary renal cell carcinoma, to Brown Norway rats was necropsied at 24 months of age. At necropsy, a white mass about 1 centimeter in size was observed in the thoracic cavity, and the mass partly adhered to the esophagus and the diaphragm. Histologically, the mass was clearly circumscribed by connective tissue, and consisted of neoplastic cuboidal epithelial cells that showed cystic tubular proliferation. Some islands of well-differentiated hepatocytes and some vessels were observed in the mass. Immunohistochemically, the tumor cells were strongly positive for cytokeratin and partly positive for vimentin but were negative for mesothelin and Von Willebrand Factor. The positive rate for Ki-67 was 2.4%. Based on these histological and immunohistochemical evidences, we diagnosed this tumor as a cystic cholangioma that might have arisen from the ectopic hepatic tissue in the thoracic cavity.  相似文献   
5.
6.
Amyloid beta peptide (Abeta), the pathogenic agent of Alzheimer's disease (AD), is a physiological metabolite in the brain. We examined the role of neprilysin, a candidate Abeta-degrading peptidase, in the metabolism using neprilysin gene-disrupted mice. Neprilysin deficiency resulted in defects both in the degradation of exogenously administered Abeta and in the metabolic suppression of the endogenous Abeta levels in a gene dose-dependent manner. The regional levels of Abeta in the neprilysin-deficient mouse brain were in the distinct order of hippocampus, cortex, thalamus/striatum, and cerebellum, where hippocampus has the highest level and cerebellum the lowest, correlating with the vulnerability to Abeta deposition in brains of humans with AD. Our observations suggest that even partial down-regulation of neprilysin activity, which could be caused by aging, can contribute to AD development by promoting Abeta accumulation.  相似文献   
7.
The distribution of zinc, manganese, copper, cobalt, and nickel in Andosols was investigated. Sixty nine soil samples were collected from different horizons of an Andosols profile in Miyakonojo Basin in south Kyushu, Japan, The total contents of heavy metals were determined by digestion and four extraction solutions, 1 M NH4Ac (ammonium acetate) pH 4.5, 0.1 M HCl, 0.01 M EDTA (ethylenediaminetetraacetic acid) pH 6.5, and 0.005 M DTPA (diethylenetri-aminepentaacetic acid) pH 7.3 were used to determine the contents of available Zn, Mn, Cu, Co, and Ni in Andosols in relation to the organic carbon content. The results of the extraction analysis showed that by the use of 0.1 M H Cl high value of extracted heavy metals in the upper layers of the humus horizons were obtained while EDTA extraction yielded a large amount of the above mentioned metals in the high humus horizons. The extractable heavy metals contents were high and these metals closely related to the organic carbon content mostly in the humus horizons in the profile. Where, biocycling process may play an important role in the concentration of heavy metals. Based on the study, it was found that the total content of Zn increased towards the C horizons or pumice layers in the soil profile. Such a trend was also found in the case of the Mn content. While the Cu content in the humus horizons was much higher in the upper part of each humus horizon. According to this study the distribution of heavy metals, Cu (organic matter complexes) in the Andosols profile was more stable than that of Zn (organic matter complexes) in soils. It was shown that Zn in the surface humus horizon was enriched but that some amount was leached under buried conditions. The same phenomenon was also observed in the distribution of Mn in the profile. The movement of Co and Ni in the soil profile was limited, as evidenced by the sharp reduction in the concentrations of these two metals in buried soils.

Hence, it is concluded that the distribution of Zn, Mn, Cu, Co, and Ni was considerably higher in the humus horizons of the Andosols profiles.  相似文献   
8.
An 18-month-old male Brown Norway (BN) rat showed a grayish-white subcutaneous mass in the right cheek. Histologically, the mass was composed of highly pleomorphic cells producing collagen. Immunohistochemical analysis showed that the tumor cells were strongly positive for vimentin and partially positive for Ki-67; however, they were negative for ED-1, ED-2, S-100, cytokeratin, desmin and myoglobin. Ultrastructurally, the cytoplasms of the tumor cells contained well-developed rough endoplasmic reticulum. Thus, the tumor had no characteristic feature other than collagen production and was diagnosed as a fibrosarcoma.  相似文献   
9.
It is not known why sweet potato (Ipomoea batatas) cultivated in tropical regions tolerates acid soil. Here, we report the involvement of mycorrhizal symbiosis in this tolerance. Plants were grown in root-boxes filled with either acidic soil (pH 4.2) or the same soil amended with lime (pH 5.2) for 30 d in a growth chamber. In the inoculated treatments, the percentage of root length colonized by Gigaspora margarita was not affected by soil pH (23±9% at pH 4.2 vs. 30±12% at pH 5.2). The root and shoot dry weights of the non-mycorrhizal plants at pH 4.2 were 27 and 35%, respectively, of those at pH 5.2. The root and shoot dry weights of the mycorrhizal plants at pH 4.2 were 70 and 51% of those at pH 5.2. Growth promotion in mycorrhizal plants was significant only at pH 4.2 (2-fold increase in whole plant dry weight), but not at pH 5.2. As a result, no significant difference was detected in whole plant dry weight between the mycorrhizal plants at pH 4.2 and non-mycorrhizal plants at pH 5.2. The mycorrhizal plants at pH 4.2 showed reduced toxic symptoms of Mn (brown specks on mature leaves) and Al (poor root growth) compared to non-mycorrhizal ones, but tissue concentrations of P, K and Ca did not increase in mycorrhizal plants. We assume that the mycorrhizal colonization can reduce toxic effects of those elements while the exact mechanisms should be further investigated.  相似文献   
10.
Radish (Raphanus sativus cv. Akamaru‐Hatsukadaikon) was grown for several experiments in a glasshouse with zinc (Zn) supply in the nutrient solution. Lack of Zn resulted in stunted growth and reduced leaf of radish shoots were observed. Two‐dimensional thin layer chromatography (TLC) and gas chromatography‐mass spectrometry (GC‐MS) analysis revealed the presence of endogenous indole‐3‐acetic acid (IAA) in Zn‐deficient radish shoots. An estimate has been made of alkali‐labile (1 and 7N NaOH) IAA in Zn‐deficient radish shoots with the use of gas chromatography (GC). The level of 7N NaOH‐labile IAA (peptidic + ester + free) and IN NaOH‐labile IAA (ester + free) in Zn‐deficient radish shoots was almost the same as that of control radish shoots. These results suggest that Zn nutrition did not affect the level of endogenous IAA in radish shoots.  相似文献   
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