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排序方式: 共有202条查询结果,搜索用时 15 毫秒
101.
Q Fang J Wang YY Hao H Li JX Hu GS Yang JH Hu 《Reproduction in domestic animals》2017,52(6):1061-1066
Microbial environment is one of the important factors that affect the quality of preserved semen. Iodine methionine (IM), participating in the production and activation of metabolic enzymes, is a new type of amino acid chelate. To date, there has been no report to evaluate the effects of IM on boar semen preservation at 17°C. This study was designed to investigate the effects of IM on boar sperm quality and reproductive performance during liquid storage at 17°C and its antibacterial effect. Semen samples collected from six Yorkshire boars were diluted with basic liquid containing different concentrations of IM (0, 20, 40, 80, 160 and 320 μM). Subsequently, sperm motility, plasma membrane integrity and acrosome integrity were determined. After 6 days of preservation, the difference in microbial composition between control group and 80 μM IM group was compared using 16S rDNA sequencing, and the effects of IM on reproductive performance were also compared and analysed between the two groups. The results demonstrated that 20, 40 and 80 μM IM improved boar sperm motility, plasma membrane integrity and acrosome integrity. 80 μM IM was the optimum concentration. Conversely, 160 and 320 μM IM resulted in deleterious consequences to boar sperm quality compared to the control group and other treatment groups (p < .05). After 6 days of preservation, sperm motility, plasma membrane integrity and acrosome integrity were 56.0%, 51.8% and 59.4%, respectively. There was no significant difference in non‐return rate between the two groups (p > .05). But the litter size of 80 μM IM group was significantly higher than that of control group (p < .05). 80 μM IM inhibited proliferation of the phylum Proteobacteria and the genus Staphylococcus as well as Pseudomonas (p < .05). Further studies are required to understand the antibacterial mechanism of IM in liquid‐preserved boar semen. 相似文献
102.
Yoon S Yoo HJ Shim NR Baek SY Kim BS Kim JB Jun EJ Son YK Lee SY Yoo YH 《Anatomia, histologia, embryologia》2003,32(2):80-88
This study was undertaken to investigate the immunohistochemical characterization of different subpopulations of macrophages and dendritic cells (DCs) of the spleen, thymus, tongue and heart in cyclophosphamide (CY)-induced immunosuppressed rat. After CY treatment, remarkably, ED1+, ED2+ and ED3+ macrophage subpopulations, in general exhibited signs of cellular activation such as an increase in number and size of cell, and an upregulation of the ED1, ED2 and ED3 reactive surface molecule expression in all the organs studied, except for some macrophage subpopulations including ED1+ macrophages in the non-lymphoid tissues. Subpopulations of DCs showed a differential sensitivity to CY. Lymphoid DCs were more sensitive to CY than non-lymphoid interstitial DCs. CY induced a conspicuous upregulation of intercellular adhesion molecule-1 (ICAM-1) expression in the vascular endothelial cells, splenic marginal zone and thymic cortex. In this study, we demonstrated the in vivo effects of CY treatment on subpopulations of macrophages and DCs as well as on ICAM-1 expression in the rat spleen, thymus, tongue and heart. Moreover, our results shed more light on the activation effects of CY on certain subpopulations of macrophages, on the differential sensitivity of DCs to CY between the immature and mature ones, on the functional role of different subpopulations of macrophages, and on the significance of upregulated ICAM-1 expression in the splenic marginal zone and thymic cortex after CY treatment. 相似文献
103.
In Jeong Kang Seung-Han Kim Yong Weon Seo Min Jeong Seo Hyeong Kwon Shim Dong Bum Shin Sunggi Heu 《Journal of Crop Science and Biotechnology》2015,18(4):279-284
Wildfire, caused by Pseudomonas amygdali pv. tabaci is one of the most destructive bacterial diseases and was recognized as a disease of soybean in 1943. Wildfire has been seen a steady increase in the incidence and prevalence on some cultivars of soybean in Korea by climatic changes but there is little information on effective control measures for wildfire or soybean varieties showing complete resistance to the disease. In this study, the efficient and reliable screening method to evaluate soybean genotype for resistance to P. amygdali pv. tabaci in field had been developed. In order to determine the host resistance of the soybean cultivar against P. amygdali pv. tabaci, development of symptom by infiltration inoculation was evaluated. Significant differences between susceptible plants and resistant plants were observed through these assays. Based on these results, ‘Shinpaldal2’, ‘Daepung’ are resistant to wildfire compared to ‘Hwangeum’, ‘Taekwang’. The optimum temperature of this pathogen was between 20-25°C and when the pathogen was in the optimum temperature, the responses of susceptible or resistant cultivar were dramatically different. Prior to initiation of resistance breeding of soybean wildfire, it is imperative to set uniform resistance screening techniques. The obtained results can be effectively used to enhance the selection of wildfire resistance as well as directly applied in resistant soybean development. Resistant lines identified through this assay could be directly used in soybean breeding programs for wildfire resistance. 相似文献
104.
105.
enVix is a novel regenerated cellulosic fiber, which is prepared from cellulose diacetate fiber using environmentally friendly
manufacturing process. Vat dyeing properties of the enVix were investigated and compared with those of regular viscose rayon.
The enVix exhibited better dyeability than viscose rayon. The colour yields of vat dyes on the enVix were found to be dependent
on dyeing temperature as well as the amount of levelling agent and salt. Good build-up and good to excellent fastness properties
were obtained on the enVix fabric. 相似文献
106.
The effects of increasing dietary concentrations of phosphorus on growth, feeding efficiency and body composition were studied in the tiger barb (Barbus tetrazona) (Bleeker, 1855). Juvenile tiger barbs (initial weight 0.33 ± 0.02 g) were fed purified diets containing graded levels of KH2PO4 to provide 0.17–1.57% available dietary phosphorus for 8 weeks in freshwater glass aquaria. The weight gain, feeding efficiency and mineral composition of the whole body and bone were significantly (p<0.05) affected by dietary phosphorus. Growth response data calculated by broken line analysis showed that the minimum dietary phosphorus level required for maximum growth was 0.52%. The carcass protein, fat and ash contents but not moisture were affected by various dietary phosphorus levels. Fish fed a low-phosphorus diet had high body crude fat. 相似文献
107.
Poly(ethylene terephthalate) (PET) and poly(ethylene glycol) (PEG) copolymers cross-linked with pentaerythritol, a four-way
cross-linker, are prepared to compare their mechanical and shape memory properties with the one cross-linked by glycerol.
Composition of PEG and pentaerythritol is varied to search for the one with the best mechanical and shape memory properties.
The highest shape recovery rate is observed for the copolymer composed of 30 mol% PEG-200 and 2.5 mol% pentaerythritol. Four-way
cross-linking by pentaerythritol significantly improves shape recovery rate and retention of high shape recovery rate after
repeated use compared to the one cross-linked by glycerol, a three-way cross-linker, and difference and advantage of additional
cross-linking point are discussed. 相似文献
108.
Apparent and true values of protein digestibility (APD vs. TPD) and amino acid availability (AAAA vs. TAAA) of casein, gelatin, fish meal, shrimp meal, soybean meal and spirulina meal were determined for juvenile Chinese hairy crab Eriocheir sinensis H. Milne‐Edwards. Assay diets were prepared by incorporation of 20% of a protein source into a reference diet. A protein‐free diet (PFD) was used to estimate the metabolic faecal nitrogen (MFN) content and amino acid composition (MFAA). MFN content was 445.3 mg 100 g?1 PFD. MFAA ranged from 19.6 mg 100 g?1 PFD for tryptophan to 228.5 mg 100 g?1 PFD for glutamic acid. Casein and gelatin trended towards higher APD, while fish meal had the lower APD and TPD. Although there was reasonable agreement between protein digestibility and average amino acid availability, protein sources had significant effects on AAAA and TAAA. For total amino acids and most individual amino acids, casein and gelatin were relatively higher both in AAAA and in TAAA, soybean meal and spirulina meal intermediate, while fish meal was lower. Data of AAAA and TAAA suggest that soybean meal and spirulina meal could be used as substitutes for animal proteins. Individual AAAAs and TAAAs were variable within and among protein sources. Those results suggest that determination of amino acid availabilities is necessary for the more accurate and economical feed formulation. 相似文献
109.
Sullim Lee Geum Jin Kim Hyukbean Kwon Joo-Won Nam Ji Yun Baek Sang Hee Shim Hyukjae Choi Ki Sung Kang 《Marine drugs》2021,19(4)
Menopause, caused by decreases in estrogen production, results in symptoms such as facial flushing, vaginal atrophy, and osteoporosis. Although hormone replacement therapy is utilized to treat menopausal symptoms, it is associated with a risk of breast cancer development. We aimed to evaluate the estrogenic activities of Spartina anglica (SA) and its compounds and identify potential candidates for the treatment of estrogen reduction without the risk of breast cancer. We evaluated the estrogenic and anti-proliferative effects of extracts of SA and its compounds in MCF-7 breast cancer cells. We performed an uterotrophic assay using an immature female rat model. Among extracts of SA, belowground part (SA-bg-E50) had potent estrogenic activity. In the immature female rat model, the administration of SA-bg-E50 increased uterine weight compared with that in the normal group. Among the compounds isolated from SA, 1,3-di-O-trans-feruloyl-(-)-quinic acid (1) had significant estrogenic activity and induced phosphorylation at serine residues of estrogen receptor (ER)α. All extracts and compounds from SA did not increase MCF-7 cell proliferation. Compound 1 is expected to act as an ERα ligand and have estrogenic effects, without side effects, such as breast cancer development. 相似文献
110.