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91.
Two purified diets supplemented with 0 or 20 000 IU vitamin D3 kg?1 of diet were fed to amago salmon, Oncorhynchus rhodurus (Jordan & McGregor), for 22 weeks. The feeding stopped when fish with deficiency signs including reduced growth, and caudal region and fin tip damage increased in number. Deficient fish had a thinned epidermis consisting of atrophied and necrotic epidermal cells over the basal cells. In lesions of the caudal peduncle, the skin and the underlying musculature were extensively necrotized. The liver showed degenerated and necrotic hepatocytes. Respiratory epithelium and cardiac muscle fibres were swollen. Hypocalcaemia was evident. No pathological changes were found in bone, eyes, brain and alimentary tract. The control groups fed a nutritionally complete diet grew well and displayed no pathological changes. The pathological changes were reversed after 4 weeks of feeding of vitamin-D3-suppliemented diet.  相似文献   
92.
Phosphoglucoisomerase (PGI) was studied to establish the genetic system of the isozymes in section Cepa of Allium. The results of isozyme analyses using 15 cultivars and clones in two cultivated species A. fistulosum and A. cepa, eight strains in four wild species A. altaicum, A. galanthum, A. oschaninii and A. vavilovii and a total of 10 hybrids between A. fistulosum and A. cepa and between the cultivated and wild species revealed that: 1) PGI was a dimeric enzyme; 2) the two cultivated and four wild species had a common gene locus Pgi-1 where six alleles were identified; and 3) A. fistulosum had Pgi-1 F-1 and Pgi-1 F-2, A. cepa had Pgi-1 A-1 and Pgi-1 A-2, A. altaicum had Pgi-1 F-1, A. galanthum and A. vavilovii had Pgi-1 A-1, and A. oschaninii had Pgi-1 A-1, Pgi-1O-1 and Pgi-1 O-1. The intra- and inter-specific polymorphisms of PGI isozymes are expected to be valuable tools for the genetics and practical utilization of the wild species in section Cepa.  相似文献   
93.
Black soybean seed coat extract (BE) is a polyphenol-rich food material consisting of 9.2% cyanidin 3-glucoside, 6.2% catechins, 39.8% procyanidins, and others. This study demonstrated that BE ameliorated obesity and glucose intolerance by up-regulating uncoupling proteins (UCPs) and down-regulating inflammatory cytokines in C57BL/6 mice fed a control or high-fat diet containing BE for 14 weeks. BE suppressed fat accumulation in mesenteric adipose tissue, reduced the plasma glucose level, and enhanced insulin sensitivity in the high-fat diet-fed mice. The gene and protein expression levels of UCP-1 in brown adipose tissue and UCP-2 in white adipose tissue were up-regulated by BE. Moreover, the gene expression levels of major inflammatory cytokines, tumor necrosis factor-α and monocyte chemoattractant protein-1 were remarkably decreased by BE in white adipose tissue. BE is a beneficial food material for the prevention of obesity and diabetes by enhancing energy expenditure and suppressing inflammation.  相似文献   
94.
Many cases of encephalitic disease with unknown etiologies have been reported in specific breeds of small dogs. High mobility group box 1 (HMGB1) in neuronal cells was recently found to be a novel cytokine-like mediator that is a marker of neuronal necrosis and inflammation. The aim of this study was to determine whether HMGB1 levels are elevated in the cerebrospinal fluid (CSF) of dogs suspected of having encephalitis. CSF was obtained from 31 dogs that were diagnosed with an encephalitic disease by clinical examinations and magnetic resonance image (MRI) scanning. The CSF samples were analyzed via western blotting (WB) and an enzyme-linked immunosorbent assay (ELISA) with a polyclonal antibody against HMGB1. The mean HMGB1 concentration was significantly higher in the encephalitic dogs than that in the healthy controls. The concentrations of HMGB1 were correlated with the cell counts and total protein concentrations, which are known CSF indicators of the neuronal inflammation associated with encephalitis. These results suggest that HMGB1 protein in CSF confirms the presence of necrosis and inflammation in most cases of canine encephalitis and that HMGB1 will be a new indicator of encephalitis.  相似文献   
95.
ABSTRACT: Group A rotaviruses (GARs) are one of the most common causes of diarrhea in suckling pigs. Although a number of G and P genotypes have been identified in porcine GARs, few attempts have been made to study the molecular epidemiology of these viruses associated with diarrhea outbreaks within a farm over an extended period of time. Here, we investigated the molecular characteristics of GARs that caused four outbreaks of diarrhea among suckling pigs in a farrow-to-finish farm over the course of a year. G and P genotyping of GARs detected at each outbreak demonstrated genetic diversity in this farm as follows: G9P[23] was detected at the first outbreak, G9P[13]/[22] and G9P[23] at the second, G3P[7] at the third, and G9P[23], G5P[13]/[22], and P[7] combined with an untypeable G genotype at the fourth. Sequence analysis of the detected GARs revealed that such genetic diversity could have resulted not only from the introduction of new GAR strains, but also from gene reassortment between GAR strains within the farm. Further, the GAR strain carrying the untypeable G genotype was shown to be a novel porcine GAR bearing a new G26 genotype, as confirmed by the Rotavirus Classification Working Group.  相似文献   
96.
The carboxylesterase cauxin is a major urinary protein in cats that is also found in seminal fluid (SF). This study investigated cauxin in feline SF including biochemical features, concentration, distribution and gene expression in epididymal tissue, and its reaction with acylglycerol substrates.Monomeric, dimeric, and/or multimeric forms of cauxin carrying N-glycosylations were detected on Western blots of feline SF but most were monomeric. Cauxin concentrations were markedly lower in SF (0.042 ± 0.020 mg/mL) than in urine (∼0.5 mg/mL) and cauxin gene expression was 60-fold lower in the epididymis than in the kidney. Immunohistochemical examination localised cauxin within the stereocilia and cytoplasm of epithelial cells lining the caput and corpus epididymis. Cauxin-positive spermatozoa were detected in the lumen of the cauda epididymis but not in the cytoplasm of the epithelial cell lining. Using an in vitro assay, cauxin hydrolysed saturated 1-mono- but not di- and tri-acylglycerols. The results suggest that cauxin secreted from the caput and corpus epididymis acts as an esterase on lipid within feline SF.  相似文献   
97.
A simple capillary electrophoretic method is described for the simultaneous determination of soluble oxalate and nitrate in forage grasses. Grass samples were ground and extracted with water. The extracts were filtered and submitted to capillary electrophoresis. Electrophoresis was performed in a 75 microm x 50 cm fused silica capillary with 30 mM sodium sulfate containing an electroosmotic flow modifier under constant voltage at -8 kV. Separated oxalate and nitrate were detected with direct UV absorption at 214 nm. The present method can be used for routine monitoring of the concentration of soluble oxalate and nitrate in grasses.  相似文献   
98.
Serological analysis was performed to detect Toxoplasma gondii and Neospora caninum infection in seals in Hokkaido. Serum samples were collected from 322 Kuril harbor seals (Phoca vitulina stejnegeri) at Nosappu, Akkeshi and Erimo, from 46 spotted seals (P. largha) at Nosappu, Erimo, Yagishiri Island, Hamamasu and Syakotan, and from 4 ribbon seals (P. fasciata) and a bearded seal (Erignathus barbatus) at Nosappu between 1998 and 2006. Recombinant surface antigen of T. gondii (SAG2t) and N. caninum (NcSAG1t) were used as antigens for ELISA to detect antibodies. Antibodies against SAG2t were detected from 4% of 77 Kuril harbor seals at Nosappu in 2005. Antibodies against NcSAG1t were detected from 2% (1/66) in 2003, 5% (4/79) in 2004 and 10% (8/77) in 2005 of Kuril harbor seals and 11% of 9 spotted seals in 2004 sampled at Nosappu. Eight percent of 12 Kuril harbor seals from Akkeshi and 25% of 4 spotted seals from Erimo in 2005 also contained antibodies against NcSAG1t. These suggest sporadic infection of T. gondii and N. caninum in Kuril harbor seals and spotted seals in Hokkaido. Of the ELISA-positive seals, 2 seals having anti-SAG2t antibodies and 3 seals having anti-NcSAG1t antibodies in 2005 were judged to be juveniles that have no maternal antibodies. These suggest that the protozoan infections have occurred in recent years. Infection of terrestrial protozoa such as T. gondii and N. caninum in seals indicates that the sea environment has been contaminated with protozoa.  相似文献   
99.
黑龙江省安达市草地碱化后土壤物理性状变化   总被引:2,自引:0,他引:2  
调查了安达市盐碱地生物资源环境研究中心试验区羊草Leymus chinensis地土壤物理性状,包括土壤硬度、含水量、饱和导水率、粒径分布、剖面特征和土壤温度等.阐明土地碱化对土壤物理性质的影响,为安达市以及松嫩平原生态环境的修复和土地资源的永续利用提供科学依据.同时,讨论了地下水化学成分和土壤冻融变化对碱化的可能影响,认为在没有植被覆盖的条件下,冻融变化会加剧土壤的碱化程度.  相似文献   
100.
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