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1.
An apocrine adenocarcinoma was observed in the subcutis of the abdomen of golden hamster. Histologically, the tumor cells irregularly formed multiple layers of cysts and some detached cells were presented in the cystic space. PAS stain with alpha-amylase digestion revealed PAS-positive alpha-amylase-resistant granules in the cytoplasm. Immunohistochemically, cytokeratin was demonstrated in the tumor cells. By electron microscopy, the tumor cells had an oval nucleus with invagination, abundant cytoplasmic organelles and microvilli protruding into the intercellular spaces.  相似文献   
2.
Partially purified vascular permeability (VP) factor (VPF) of Bacillus cereus induced fluid accumulation in the ligated intestinal loops of mouse (MIL) and rabbit (RIL), suggesting that the VP activity may correlate with fluid accumulation in ligated intestinal loops of these animals. Fluid accumulation was observed at 6-8 hr in 55-67% of mouse intestinal loops inoculated with 40-50 immunodiffusion units (IDU) of partially purified VPF, whereas it was found at 2 hr in all loops with 400-600 IDU of partially purified VPF. In rabbit intestinal loops with 120-190 IDU of partially purified VPF, fluid accumulation was observed at 6 hr. From these findings, VPF produced by B. cereus can be easily detected in both MIL and RIL. The intestinal tissue of mouse intestinal loops was histopathologically damaged at different concentrations of the VPF to induce fluid accumulation. With 50 IDU of partially purified VPF, severe edema was found in the laminia proprial layer and submucosa. With 600 IDU of partially purified VPF, on the other hand, severe necrosis in the surface epithelium of villus and laminia proprial layer, and hyperemia in the submucosa were observed, suggesting that partially purified VPF may be cytotoxic and/or intestinecrotic.  相似文献   
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Data from six primiparous and nine multiparous Holstein cows were used to clarify the difference of Ca and P mobilization between primiparous and multiparous cows during early lactation. The dry matter intake (DMI) of primiparous cows was lower (P < 0.01) than those of multiparous cows. Milk yield was lower in primiparous cows at 7, 14, 21 (P < 0.01), and 28 days (P < 0.05) after parturition. There was no significant difference in milk Ca and P concentrations between primiparous and multiparous cows. There were no significant differences in plasma Ca and P concentrations between primiparous and multiparous cows. The plasma P level at 7 days postpartum in primiparous cows was lower (P < 0.05) than 28 days postpartum. The concentration of plasma osteocalcin (OC) measured as bone formation marker of primiparous cows was significantly higher than multiparous cows (P < 0.01) at 21 and 28 days postpartum. The urinary deoxypyridinoline (DPD) as bone resorption marker of primiparous cows tended to be higher (P < 0.10) than multiparous cows at 21 days after parturition and decreased to the same level as that of multiparae toward the peak lactation. These results show that Ca and P mobilization of primiparous cows are more active than multiparous cows.  相似文献   
6.

Background

In veterinary medicine, congenital methemoglobinemia associated with nicotinamide adenine dinucleotide (NADH)‐cytochrome b5 reductase (b5R) deficiency is rare. It has been reported in several breeds of dogs, but little information is available about its etiology.

Objectives

To analyze the NADH‐cytochrome b5 reductase gene, CYB5R3, in a Pomeranian dog family with methemoglobinemia suspected to be caused by congenital b5R deficiency.

Animals

Three Pomeranian dogs from a family with methemoglobinemia were analyzed. Five healthy beagles and 5 nonrelated Pomeranian dogs without methemoglobinemia were used as controls.

Methods

Methemoglobin concentration, b5R activity, and reduced glutathione (GSH) concentration were measured, and a turbidity index was used to evaluate Heinz body formation. The CYB5R3 genes of the affected dog and healthy dogs were analyzed by direct sequencing.

Results

Methemoglobin concentrations in erythrocytes of the affected dogs were remarkably higher than those of the control dogs. The b5R activity of the affected dogs was notably lower than that of the control dogs. DNA sequencing indicated that this Pomeranian family carried a CYB5R3 gene missense variant (ATC→CTC at codon 194) that resulted in the replacement of isoleucine (Ile) by leucine (Leu).

Conclusions and Clinical Importance

This dog family had familial congenital methemoglobinemia caused by b5R deficiency, which resulted from a nonsynonymous variant in the CYB5R3 gene. This variation (c.580A>C) led to an amino acid substitution (p.Ile194Leu), and Ile194 was located in the proximal region of the NADH‐binding motif. Our data suggested that this variant in the canine CYB5R3 gene would affect function of the b5R in erythrocytes.  相似文献   
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Oriental persimmon (Diospyros kaki) originated in Eastern Asia, and many indigenous cultivars have been developed in China, Japan, and Korea. These cultivars are classified into four groups based on their natural astringency loss on the tree and seed formation: pollination-constant non-astringent (PCNA), pollination-variant non-astringent (PVNA), pollination-constant astringent (PCA), and pollination-variant astringent (PVA). PCNA is the most desirable type because the fruit can be eaten without any postharvest treatment; therefore, one of the goals of our persimmon breeding programs is to release superior PCNA cultivars. The PCNA genotype is recessive to the other three non-PCNA genotypes, and PCNA-type F1 offspring are obtained exclusively from crosses among PCNA genotypes. Moreover, the number of superior PCNA cross-parents have been limited. In the late 1980s, inbreeding depression became obvious, especially in terms of fruit size, tree vigor, and productivity. To mitigate the inbreeding, a backcross program using PCNA [(non-PCNA × PCNA) × PCNA] was started in 1990. This process, however, was inefficient because only 15% of the offspring were PCNA, and all offspring had to be grown to the fruiting stage. Therefore, molecular markers linked to the PCNA locus were developed for discriminating PCNA offspring. A molecular marker linked to Chinese PCNA has also been developed.  相似文献   
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The growth and morphology of rumen methanogenic archaea (15 strains of 10 species in 5 genera, including 7 strains newly isolated in the present study) and bacteria (14 species in 12 genera) were investigated using unsupplemented in vitro pure cultures and cultures supplemented with cashew nut shell liquid (CNSL) and its phenolic compound components, anti-methanogenic agents for ruminant animals. Growth of most of the methanogens tested was inhibited by CNSL and alkylphenols at different concentrations ranging from 1.56 to 12.5 μg/ml. Of the alkylphenols tested, anacardic acid exhibited the most potent growth inhibition. Three gram-negative bacterial species involved in propionate production were resistant to CNSL and alkylphenols (>50 μg/ml). All the methanogens and bacteria that were sensitive to CNSL and alkylphenols exhibited altered morphology; disruption of the cell surface was notable, possibly due to surfactant activity of the tested materials. Cells division was inhibited in some organisms, with cell elongation and unclear septum formation observed. These results indicate that CNSL and alkylphenols, particularly anacardic acid, inhibit both rumen bacteria and methanogens in a selective manner, which could help mitigate rumen methane generation.  相似文献   
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