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101.
102.
Adipose tissue in various stages of fish oil-induced yellow fat disease in the rat had the same acid phosphatase and 5-nucleotidase activity pattern as similar stages of the disorder in mink and pig. A weak acid phosphatase and 5-nucleotidase activity was seen in interstitial lipofuscin-laden macrophages in "stage M" yellow fat disease without fat cell degeneration. Activity of these macrophagic enzymes increased when there was fat cell degeneration ("stage S" and "stage E" yellow fat disease). This different phosphatase activity in the same cell type may result from phagocytosis of substrates with variable digestibility. Macrophages directly surrounding affected fat cells in steatitis areas ("stage S" and "stage E") had strong acid phosphatase and 5-nucleotidase activity. As in the pig, increased 5-nucleotidase activity was found in affected fat cells, which probably indicates plasma membrane damage. Increased nonspecific esterase activity occurred around affected fat cells. Only a small part of this esterase activity originated from inflammatory cells. This indicates that an increase of esterase activity in degenerating adipose tissue may be an endogeneous process in this tissue.  相似文献   
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104.
Based on the time that symptoms of blackleg become evident in the field and the various ways of inoculation, it is concluded that the spread of symptom expression is due to the depth at which the bacteria penetrate into the interior of the tubers. Moreover, it is demonstrated that it is not the closed lenticels which prevent penetration, but the absence of a waterfilm in the intercellular spaces of the tuber tissue.  相似文献   
105.
Marine sponge-derived endozoic fungi have been gaining increasing importance as promising sources of numerous and unique bioactive compounds. This study investigates the phytochemical profile and biological activities of the ethyl acetate extract of Penicillium chrysogenum derived from Cliona sp. sponge. Thirty-six compounds were tentatively identified from P. chrysogenum ethyl acetate extract along with the kojic acid (KA) isolation. The UPLC-ESI-MS/MS positive ionization mode was used to analyze and identify the extract constituents while 1D and 2D NMR spectroscopy were used for kojic acid (KA) structure confirmation. The antimicrobial, antioxidant, and cytotoxic activities were assessed in vitro. Both the extract and kojic acid showed potent antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa with MIC 250 ± 0.82 µg/mL. Interestingly, the extract showed strong antifungal activity against Candida albicans and Cryptococcus neoformans with MIC 93.75 ± 0.55 and 19.53 ± 0.48 µg/mL, respectively. Furthermore, KA showed the same potency against Fusarium oxysporum and Cryptococcus neoformans with MIC 39.06 ± 0.85 and 39.06 ± 0.98 µg/mL, respectively. Ultimately, KA showed strong antioxidant activity with IC50 33.7 ± 0.8 µg/mL. Moreover, the extract and KA showed strong cytotoxic activity against colon carcinoma (with IC50 22.6 ± 0.8 and 23.4 ± 1.4 µg/mL, respectively) and human larynx carcinoma (with equal IC50 30.8 ± 1.3 and ± 2.1 µg/mL, respectively), respectively. The current study represents the first insights into the phytochemical profile and biological properties of P. chrysoenum ethyl acetate extract, which could be a promising source of valuable secondary metabolites with potent biological potentials.  相似文献   
106.
为阐明全球气候变暖和微塑料复合胁迫对长牡蛎(Crassostrea gigas)免疫应答、氧化应激和能量代谢的影响,本研究采用3个微塑料(microplastics, MPs)水平[无微塑料、小粒径聚苯乙烯微塑料(SPS-MPs,6μm)和大粒径聚苯乙烯微塑料(LPS-MPs,50~60μm)]和2个温度水平(20℃和25℃)对长牡蛎进行了为期21 d的单一和复合暴露,检测分析了各组长牡蛎血细胞功能[吞噬活性、活性氧(reactive oxygen species,ROS)含量]、糖原含量以及免疫相关基因表达的变化。研究结果表明,SPS-MPs暴露能增加长牡蛎血淋巴细胞中ROS含量,降低血细胞吞噬活性,揭示SPS-MPs毒性作用更强。升温与微塑料的协同作用增加了长牡蛎消化腺组织中的糖原含量。实时荧光定量PCR结果显示,升温与SPS-MPs复合暴露组长牡蛎消化腺组织通过上调热休克蛋白90 (heat shock protein90, HSP90)、核因子κB抑制蛋白(inhibitor of NF-κB, IκB)和p53基因表达量进行免疫应答;升温与微塑料的拮抗作用增加了鳃组织p53基...  相似文献   
107.
为探究适应冀西北地区旱作马铃薯高产高质的栽培技术,本试验以马铃薯品种京张薯3号为试验材料,研究了在旱作雨养条件下,不同覆膜材料和增施有机肥对旱作马铃薯植株形态、光合效应、产量和品质的影响。试验结果表明:与对照相比,覆膜和增施有机肥处理FOB和FOS可以提高马铃薯出苗率,缩短出苗天数,增加植株株高和茎粗。FOS、FOB和FOW处理在马铃薯块茎形成期、块茎膨大期、淀粉积累期三个时期,显著提高了马铃薯净光合速率、气孔导度和蒸腾速率。从产量和产量构成因素看,FOS和FOB处理单株结薯数比对照分别增加37.9%和25.2%,单株结薯重提高38.1%和33.7%,折合667 m2产量比对照提高31.29%和27.82%。FOS处理马铃薯淀粉含量比对照显著提高21.8%。综合各项指标,对于冀西北坝上地区,增施有机肥+渗水降解地膜是有效的旱作栽培措施。  相似文献   
108.
Storage losses in moist hay treated with propionic acid were compared with those occurring in untreated moist hay in two experiments and with field-cured hay in three experiments. Dry matter losses in treated hays ranged from 41 to 8.6% and from 1.7 to 12.6% in untreated hays. Digestible organic matter losses in both treated and untreated hays were generally greater than dry matter losses. Only in one experiment did propionic acid application significantly reduce nutrient losses in moist hays. Nutrient losses, and water-soluble carbohydrate losses in particular, were shown to be correlated with maximum and cumulative bale temperatures during storage in two of the experiments. The rise in hale temperatures during storage was reduced in all three experiments, to a greater or lesser extent, by application of the additive. Loss of propionic acid from the hay during and after application was very large. In the three experiments 86.2, 85.3 and 85.6% of the acid applied was lost by the end of the storage period. Acid distribution studies indicated that variation in acid concentration within bales was as great as between bales. It was concluded that more research is needed into applicator design and position on the baler and into alternative application methods if the benefits of propionic acid as a moist hay preservative are to be fully exploited.  相似文献   
109.
Abstract. The histological features of the disease caused by infection of turbot by Herpesvirus scophthalmi are described. Infection of epidermal cells of skin and gill resulted in the formation of giant cells showing a variety of nuclear and cytoplasmic changes associated with the replication of the virus. The effects of the condition together with possible control measures are discussed.  相似文献   
110.
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