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排序方式: 共有159条查询结果,搜索用时 31 毫秒
1.
The purpose of this study was to evaluate seasonal influences on thyroid hormone levels of healthy outdoor dogs in Hokkaido. We surveyed serum basal total thyroxine (tT4), free thyroxine (fT4), and canine thyroid-stimulating hormone (cTSH) levels, and tT4 levels after administration of TSH for a year. Basal tT4 levels decreased in January, and increased in August and September. fT4 levels increased in January and November. No significant seasonal variation was found in cTSH. tT4 levels after administration of TSH in August and November increased. These results suggested that the thyroid gland may have been activated in November. We should take seasonal variation into consideration when thyroid function is tested.  相似文献   
2.
Oxidative damage to the membrane in canine erythrocytes with inherited high Na, K-ATPase activity (HK cells) was compared with that in normal canine cells (LK cells). When 30 mM beta-acetylphenylhydrazine (APH) was applied to HK and LK cells, lipid peroxidation and hemoglobin denaturation occurred. Lipid peroxidation determined from malondialdehyde (MDA) formation was significantly lower in HK than in LK cells so far as endogenous glutathione (GSH) concentration was maintained at appropriate levels. With the depletion of GSH, MDA formation was accelerated and difference between HK and LK cells was not significant. Denatured hemoglobin bound to the membrane protein was less in HK than in LK cells. During incubation with APH, osmotic fragility increased markedly in LK cells, while HK cells showed very little change. The amounts of total lipid, total and free cholesterol, glycolipid, phospholipid and fatty acids were essentially the same in both cell types. Fatty acid compositions showed very small differences. The membrane of HK cells thus appear to have greater protection against oxidative damage induced by APH, owing to the presence of excess GSH in HK cells. The capability of HK cells to withstand oxidative damage would not be due to differences in membrane lipid compositions.  相似文献   
3.
Lactobacillus rhamnosus GG (LGG) is a well‐established probiotic strain. The beneficial properties of this strain are partially dependent on its prolonged residence in the gastrointestinal tract, and are likely influenced by its adhesion to the intestinal mucosa. The pilin SpaC subunit, located within the Spa pili structure, is the most well studied LGG adhesion factor. However, the binding epitopes of SpaC remain largely unknown. The aim of this study was to evaluate the binding properties of SpaC to the carbohydrate moieties of intestinal glycoconjugates using a recombinant SpaC protein. In a competitive enzyme‐linked immunosorbent assay, SpaC binding was markedly reduced by addition of purified mucin and the mucin oligosaccharide fraction. Histochemical staining revealed that the binding of SpaC was drastically reduced by periodic acid treatment. Moreover, in the surface plasmon resonance‐based Biacore assay, SpaC bound strongly to the carbohydrate moieties containing β‐galactoside at the non‐reducing terminus of glycolipids. We here provide the first demonstration that SpaC binds to the oligosaccharide chains of mucins, and that the carbohydrate moieties containing β‐galactoside at the non‐reducing termini of glycoconjugates play a crucial role in this binding. Our results demonstrate the importance of carbohydrates of SpaC for mucus interactions.  相似文献   
4.
Sterility in male hypogonadic (hgn/hgn) rats results from congenital testicular dysplasia caused by a single recessive gene hgn on rat chromosome 10. We recently identified an insertion mutation in the Spag5/astrin gene of hgn/hgn rats that may cause defective proliferation of immature Sertoli cells in the postnatal hgn/hgn testis. Since the pathological alterations were present in the testes at birth, we examined the involvement of defective mitosis and apoptotic cell death in embryonic development of hgn/hgn testes. Testicular hypoplasia was apparent at embryonic day (ED) 18.5. Immunostaining of hgn/hgn testes at ED 21.5 with antibody to GATA-4, which is specific for fetal Sertoli cells in the seminiferous cords, showed that the significant decrease in the number of fetal Sertoli cells was accompanied by a two fold increase in their mitotic index and abnormal mitosis and apoptosis. Prior to this, we observed a decrease in the number of BrdU-labeled cells, an increase in the number of TUNEL-positive apoptotic cells, and presence of MIS-positive apoptotic cells in hgn/hgn testes on ED 17.5 and 18.5. These results suggest that the Spag5 mutation may cause a reduction in mitotic activity and an increase in apoptosis of fetal Sertoli cells in hgn/hgn testes.  相似文献   
5.
An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses.  相似文献   
6.
水稻土CH4产生潜力及其影响因素   总被引:4,自引:1,他引:4  
培养试验所用15种水稻土样品采自全国各主要稻米产区。15种水稻土产CH4潜力差异很大,厌氧培养CH4产生率显著大于好氧培养,整个培养期(132d)总CH4产生量的变化范围为1.18~1180μgg-1(厌氧培养)和0.41~136μgg-1(好氧培养)。土壤CH4产生量受与土壤有机质含量有关的有机碳和全氮含量的显著影响,而与活性铁锰含量、颗粒组成、阳离子交换量、土壤pH等其他土壤理化性质之间无显著相关性,表明土壤有机质含量是影响CH4产生的最重要土壤性质。与类似试验的结果比较说明,土壤有机质含量对CH4产生量的影响程度可能与土样代表的空间尺度有关。  相似文献   
7.
To evaluate the effect of organic manure application with chemical fertilizers on rice yield and soil fertility under long-term double-rice cropping system, a six year field experiment was conducted continually in the paddy soil derived from Quaternary red clay in Hunan Province of southern China. Four different treatments, i.e., no nitrogen with chemical P and K (PK), swine manure only (M), N, P and K chemical fertilizers only (NPK), and half chemical fertilizers combined with half swine manure (NPKM) with four replications were included. Each N, P and K application rate was the same at all the treatments (except the N application rate at PK) and N application rate was 150 kg N ha^-1. All fertilizers were applied to soil tillage layer with once application as baseal fertilizers. The nutrients uptake rate, grain yield, nitrogen use efficiency, and soil organic matter content at each treatment were investigated. The NPKM treatment achieved the highest mean annual yield of 12.2 t ha^-1 (68% higher than that of PK). Higher dry matter accumulation and nutrients absorption were observed during the middle-late growth period in the NPKM treatment, with higher panicle number per unit and filled-grain number per panicle. Its average nitrogen use efficiency was 36.3% and soil organic matter increased by 18.5% during the experimental period in the NPKM treatment, which were significantly higher than those in the NPK treatment. Organic manure application with chemical fertilizers increased the yield and nitrogen use efficiency of rice, reduced the risk of environmental pollution and improved soil fertility greatly. It could be a good practical technique that protects the environment and raises the rice yield in this region.  相似文献   
8.
As a part of the elucidation of the pathogenesis of anemia in Theileria sergenti infection, oxidized-erythrocyte membrane proteins (OEMPs) collected from T. sergenti-infected calves were examined. The amount of OEMPs were seen to increase with the progress of the anemia and showed a maximum value around the crisis period of the infection. The increase of OEMPs coincided with band Nos. 1, 2, 2.1, 3, 4.1, 5, 6, and 7. The majority of them was located at the Triton X-100 un-extractive phase, and was confirmed as cytoskeletal proteins. This evidence indicates the enhancement of erythrocytic oxidation, and suggests that it might be one of the aggravating factors of anemia in T. sergenti infection.  相似文献   
9.
The present study was designed to evaluate the effects of tumour necrosis factor-alpha (TNF-alpha) on lactating bovine mammary functions such as milk protein secretion and the integrity of the milk-blood barrier. The effect on the induction of the systemic inflammatory response was also examined using concentrations of serum haptoglobin (Hp), a major inflammatory acute-phase protein, as an index. One hundred micrograms per mammary gland of recombinant bovine (rBo) TNF-alpha or placebo saline was individually infused into a rear mammary gland of each of four lactating cows, and milk and blood samples were collected before and 4, 8, 24, 32, 48, 96 and 168 h after infusion. In the rBoTNF-alpha-infused gland, increases of somatic cell counts were observed at 4-48 h. Although concentrations of total milk protein were not changed, compositions of milk proteins varied following rBoTNF-alpha infusion. Concentrations of caseins, alpha-lactalbumin and beta-lactoglobulin were significantly decreased at 4 and 8 h. Lactoferrin concentrations were significantly increased at 4 h. Significant infiltrations of serum albumin, immunoglobulin G1 (IgG1) and IgG2 were observed at 4 and 8 h. Elevations of the serum concentration of Hp were detected at 8-32 h, but were very small in comparison with those reported in inflammatory diseases. Changes in rectal temperature and white blood cell counts were not significant. These results show that single rBoTNF-alpha infusion into the lactating mammary gland suppresses the lactogenic function of the gland and influences the function of the milk-blood barrier, with little effect on the generalized inflammatory response.  相似文献   
10.
We previously isolated a novel immunomodulatory alpha-(1,4)(1,6)(1,2)- d-glucan-protein complex (MPG-1) from mycelia of Tricholoma matsutake in basidiomycetes. In the present study, we raised a polyclonal antibody by immunizing rabbits with MPG-1 and constructed a sandwich enzyme-linked immunosorbent assay (ELISA) system to examine the distribution of MPG-1 among edible mushrooms and related processed foods. The system detected MPG-1 quantitatively at concentrations of more than 10 ng/mL, with a coefficient of variation of less than 10% by intra-assay and interassay precision. Analysis with the system of chemically modified MPG-1 suggested that the sugar moiety was mainly involved in the detection. The system detected MPG-1 in the extracts of the fruiting bodies of T. matsutake but not in those of 34 other basidiomycete species. Moreover, a significant amount of MPG-1 was detected in the extracts of their cultured mycelia. The antigenic structure of MPG-1 was relatively stable in terms of pH and temperature. MPG-1 was detected in processed foods supplemented with T. matsutake. These results suggest that MPG-1 is distributed predominantly in T. matsutake species and that the ELISA system can detect it in processed foods supplemented with T. matsutake.  相似文献   
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