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1.
Changes in lipoprotein profiles occur in dairy cows during the periparturient period and in cows with transition cow disease. Here, the lipoprotein profiles of Holstein–Friesian dairy cows during the periparturient period were obtained by anion-exchange, high-performance liquid chromatography to evaluate the usefulness of lipoprotein profile evaluation during the periparturient period and in cows with fatty liver and milk fever. Lipoprotein levels (including total and high- (HDL-C) and low-density lipoprotein (LDL-C) cholesterol) in 10 healthy cows were low 4 weeks prepartum, with the lowest values at calving or within 1 week of calving; the values increased at 8 weeks postpartum. The lipoprotein levels were measured in 16 cows diagnosed with fatty liver (n=10) or milk fever (n=6) and compared to 10 healthy dairy cows. A significant difference was observed in HDL-C between healthy cows (at calving and 1 week postpartum), and the fatty liver and milk fever cows. Cows with fatty liver and milk fever had a lower mean HDL-C than the 10 healthy dairy cows at calving and 1 week postpartum. HDL-C might be a good indicator of energy balance for differentiating healthy cows from those with transition cow disease.  相似文献   
2.
G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is associated with various physiological functions. It is reported that the genetic variant of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation functionally relates to obesity in humans. Obesity is a common nutritional disorder also in dogs, but the genetic factors have not ever been identified in dogs. In this study, we investigated the molecular structure of canine GPR120 and searched for candidate genetic variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those of other species, and seven transmembrane domains and two N-glycosylation sites were conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus, hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs, resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant c.595C>A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly higher in dogs with higher body condition scores, i.e. 0.320 in BCS4–5 dogs, 0.175 in BCS3 dogs and 0.000 in BCS2 dogs. We conclude that c.595C>A (p.Pro199Thr) is a candidate variant relating to obesity, which may be helpful for nutritional management of dogs.  相似文献   
3.
对厚层及均匀平铺载荷条件下稻谷和糙米的微波干燥过程中的能量效率问题进行了研究。根据本研究的实验数据,如果干燥方法和工艺安排合理,微波干燥稻谷和糙米可达到较高的能量效率,甚至可达到高于传统干燥方法。在微波干燥过程中安排一定的间歇时间以发挥照射后期作用、间歇照射作用或缓苏作用,可以有效地提高微波干燥过程中的能量效率。有2h间歇的干燥工艺的能量效率是没有间歇的干燥工艺的能量效率的5倍。载荷形式对微波干燥过程中的能量效率影响也较大。微波干燥中建议采用薄层载荷形式。  相似文献   
4.
两种功能高分子材料对沙土物理性质影响的比较   总被引:1,自引:0,他引:1  
采用SEM,透水系数法、加压板法等现代测试手段,观察与分析高分子吸水树脂、固沙植被多功能高分子复合材料表面微观结构形态,比较高分子吸水树脂与固沙植被多功能高分子复合材料改良沙土后沙土的透水、保水等特性及沙土水分的有效利用情况.实验结果证明固沙植被多功能高分子复合材料比高分子吸水树脂改良沙土的效果好,使沙土的气、液、固三相比有利植物的生长,能保持高的水有效利用率.本实验结果为固沙植被多功能高分子复合材料的应用提供了新的依据.  相似文献   
5.
6.
Resistance to organophosphate (OP) and/or carbamate insecticides can be due to mutations in the acetylcholinesterase gene (Ace). Genotypes of house fly, Musca domestica L., Ace were determined in twelve laboratory maintained strains (originally from North America, Europe and Asia) and two field collected populations from New York and Florida. There were 15 Ace alleles found and 11 of the alleles coded for a susceptible form of the enzyme (i.e., V260, A316, G342 and F407). Three of the four resistance alleles were previously described, while one is new. Phylogenetic analysis of the alleles suggests multiple origins of the F407Y mutation and multiple origins of the G342A mutation that confer OP resistance. Genotyping of field collected house flies from New York and Florida populations revealed the presence of only one resistance allele, Acev10 (containing the non-synonymous mutations for A342 and Y407). All other alleles detected from the field-collected flies coded for a susceptible AChE. Thus, we were able to categorize individual flies as having homozygous susceptible (AceS/AceS), homozygous insensitive (AceI/AceI or Acev10/Acev10) or heterozygous AChE. The frequencies of AceS and AceI were not different between the NY2002 and FL2002 populations. Both populations were out of Castle-Hardy-Weinberg equilibrium, having an excess of AceS/AceI individuals and very few AceS/AceS individuals. Comparison of Ace, Vssc and CYP6D1 genotypes indicates individual house flies commonly have resistance alleles at multiple loci. Comparison of genotype data with bioassays, as well as the use of genotype data in resistance studies is discussed.  相似文献   
7.
We previously reported that the progression of staining-type hypermelanosis spontaneously ceased at a specific time and area in Japanese flounder Paralichthys olivaceus. To examine whether time is a limiting factor in the spontaneous cessation of staining, we experimentally controlled the initiation and duration of staining by manipulating the bottom substrate condition in the fish tanks. At 151 days post hatching (DPH; 11 weeks), spontaneous cessation of staining was observed in fish reared in tanks without a sandy substrate. However, staining resumed (or was initiated) in tanks where sand was removed from 11 weeks, indicating a strong but temporary effect of bottom sand and the absence of time limitation in the staining progression by 151 DPH. Extended duration of the inhibitory period of hypermelanosis expansion (9 weeks or more) aided in only a 20 % reduction of the final staining area because of the increased rate of staining expansion. The bottom sandy substrate decreased the visibility of the staining area in individuals, but this was observed only before the completion of the staining expansion. These findings are discussed in relation to possible presence of area limitation of future staining, as well as the fundamental nature of staining.  相似文献   
8.
This study aimed to characterize the physiological and morphological traits that are associated with adaptation to unflooded soil conditions in rice. Four indica rice cultivars (Puluik Arang, Badari Dhan, Shwe Nang Gyi, and Ratul), which were previously identified as highly or less adaptable to unflooded soil conditions, were grown under flooded and unflooded (soil water potential; -0.10 MPa) soil conditions. Water uptake was measured every day for three weeks, and then the leaf water potential, the stomatal conductance, the dry matter weight, shoot and root morphological traits were measured. Puluik Arang and Badari Dhan exhibited greater leaf area expansion and higher maintenance of root development under the unflooded condition than that by other cultivars. The leaf water potential and stomatal conductance of fully expanded highest leaf in Puluik Arang and Badari Dhan were not affected by unflooded soil regime. Leaf area and root morphological traits were significantly correlated with water uptake regardless of soil moisture regimes. These results suggested that Puluik Arang and Badari Dhan exhibited great water uptake capacity through physiological and morphological adaptation of shoot and root traits to unflooded condition, resulting in great biomass productivity under the condition.  相似文献   
9.
We encountered a case of cutaneous squamous cell carcinoma (SCC) in a 17-year-old female koala at a zoo. A fragile, papillary, elevated mass was found on the third digit of the right hind limb. SCC was identified histopathologically: squamous cell-like polygonal tumor cells showed a nest-like growth pattern with epidermal down growth, central keratinization and necrotic foci, and invaded dermal connective tissues. Metastatic lesions were observed in various organs, including the lung and axillary lymph node: in the lung, multiple metastatic foci similar to the primary lesion, and in the axillary lymph node, individual polygonal tumor cells infiltrated the sinusoids. Immunohistochemistry revealed that the tumor cells were positive for proliferating cell nuclear antigen, which exhibited 32–33% of labeling indices in the tumor cells. To our knowledge, this is the first report of a case of SCC in a digit of a koala.  相似文献   
10.
A 5-year-old castrated male domestic shorthair cat was diagnosed with diabetic ketoacidosis and severe insulin resistance. Although the conventional treatment for diabetic ketoacidosis was provided, the cat required frequent hospitalization because of severe dehydration and repeated diabetic ketoacidosis. We detected anti-insulin antibodies for human in this cat. Serum insulin-binding IgG levels were markedly elevated compared with those in healthy cats and other diabetic cats. We initiated prednisolone to suppress the effects of anti-insulin antibodies. After initiation of prednisolone, the cat was gradually recovered with increasing activity and appetite. Furthermore, satisfactory glycemic control was achieved with combined subcutaneous injection of insulin detemir and insulin degludec.  相似文献   
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