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201.
202.
为探明鱼类黏膜相关淋巴组织中黏液细胞对疫苗免疫的应答特性,本研究利用组织学和组织化学技术,研究了浸泡免疫灭活迟钝爱德华氏菌前后牙鲆皮肤、鳃、前肠、中肠和后肠中黏液细胞数量和特性的时序变化。苏木精-曙红(HE)、阿尔新蓝-过碘酸雪夫氏(AB-PAS)染色结果显示,免疫前皮肤主要分布含中性黏多糖的Ⅰ型黏液细胞以及含中性黏多糖和少量酸性黏多糖的Ⅲ型黏液细胞,鳃中可观察到Ⅰ、Ⅲ型以及含酸性黏多糖和少量中性黏多糖的Ⅳ型黏液细胞,前肠中主要分布Ⅰ型黏液细胞,中肠、后肠上皮中可观察到Ⅰ、Ⅲ、Ⅳ型和含酸性黏多糖的Ⅱ型黏液细胞。免疫后,牙鲆黏膜免疫相关淋巴组织中黏液细胞总量随时间呈现先增多后减少趋势,后肠在第5天达到峰值,其他于第3天达到峰值;免疫后各组织中Ⅰ型黏液细胞数量减少,含酸性黏多糖成分的Ⅱ、Ⅲ及Ⅳ型黏液细胞数量显著增多,表明疫苗免疫诱导黏液细胞成分由中性黏多糖向酸性黏多糖转变。p H 2.5和p H 1.0条件下AB染色结果显示,免疫后黏膜相关淋巴组织中酸性黏液细胞数量增多,且多数为硫酸化酸性黏液细胞。本研究结果为鱼类黏液的免疫防御功能及黏液细胞在鱼类黏膜免疫中的作用提供了理论依据。  相似文献   
203.
为了研究四种罗非鱼挥发性成份的化学成分,采用水蒸气蒸馏法提取罗非鱼挥发性成份,用气相色谱-质谱联用仪对其进行分离测定,结合计算机检索对分离的化合物进行结构鉴定,应用色谱峰面积归一化法测定各成分的相对百分含量。结果共鉴定出45种物质:奥利亚和奥尼各26种,尼罗24种,吉富18种。其中,有7种化合物为4种罗非鱼的挥发性成份所共有。2,4-二叔丁基苯酚在挥发性组份中的含量最高(奥利亚38.44%;尼罗37.34%;吉富35.21%;奥尼除外,占14.10%)。在挥发性成份中酯类、醇类、烯烃和有机酸类居多,分别有10种、6种、5种和4种,其中大部分为有特殊香味的挥发性物质,且该类物质在奥利亚、尼罗和奥尼三种罗非鱼中含量较多,在吉富中含量较少。奥尼罗非鱼中还检测出大量的特殊的挥发性物质L-抗坏血酸棕榈酸酯,其含量高达33.64%。  相似文献   
204.
唐家 《畜禽业》2011,(6):38-39
选择适合本地的3个优良品种及6个杂交组合,探讨不同组合的产仔数、初生窝重、30日龄断奶窝重、30日龄断奶成活率、90日龄成活率、90日龄个体重等生产指标,筛选最优杂交组合。结果表明:肉兔不同品种杂交生产性能明显提高;最优杂交组合为大♀×加♂杂交组合和加♀×新♂杂交组合;6个杂交组合90日龄个体重平均增加109g。  相似文献   
205.
为探究人工鱼礁区单片刺网对许氏平鲉(Sebastes schlegeli)和大泷六线鱼(Hexagrammos otakii)的选择性, 于 2021 年 10 月在荣成北部人工鱼礁区使用 4 种网目尺寸(40 mm、50 mm、60 mm、70 mm)的单片刺网进行选择性实验。在 SELECT 模型的架构下, 使用 Normal、Lognormal、Gamma、Bi-normal 模型进行选择性拟合, 根据赤池信息指数(AIC)和模型残差(MD)选择最佳拟合模型。结果表明: Lognormal 模型拟合效果最佳, 其 AIC 值和 MD 值均为最低值。根据 Lognormal 模型, 不同网目尺寸许氏平鲉的模型拟合长度分别为 114.23 mm、142.79 mm、 171.35 mm、199.90 mm; 大泷六线鱼的模型拟合长度分别为 129.67 mm、162.09 mm、194.51 mm、226.92 mm。许氏平鲉和大泷六线鱼的体长与最大剖面周长的线性关系分别为: G=0.2877L+0.7463(R2 =0.6722), G=0.2468L– 3.8531(R2 =0.6851)。选取 150 mm 作为许氏平鲉和大泷六线鱼的理论成熟体长(MBL)进行分析, 结合幼鱼留存比例, 发现网目尺寸为 60 mm 和 70 mm 的刺网能够保护人工鱼礁区许氏平鲉和大泷六线鱼的幼鱼资源。研究结果可为人工鱼礁区渔业资源的管理和养护提供参考。  相似文献   
206.
AIM:To investigate the affecting factors of detecting platelet activation by flow cytometry (FCM).METHODS:Using decoagulant of natrium citricum, anticoagnlated peripheral venous bloods from 6 healthy donors were labeled with the method of three-colour immunofluorescence assay.Platelet activation markers fibrinogen receptor (Fib-R, PAC-1) and P-selectin (CD62P) were measured.In the same time, the reproducibility of FCM was assessed.RESULTS:The platelet activation markers PAC-1 and CD62P at each time point showed significant difference(P<0.05).The ratio was increased with time extending.The positive ratio of PAC-1 and CD62P immediately measured (within 10 min) was 2.7% and 3.5% less than those at time point of 30 min.The results were measured several times under different activation levels.The coefficient of variation was less than 5%.CONCLUSION:In room temperature and with decoagulant of natrium citricum, if the measurements of PAC-1 and CD62P are finished within 30 min after sampling, good reproducibility should be achieved.  相似文献   
207.
AIM: To investigate the associated proteins and sensitive biomarkers for early diagnosis of colorectal adenocarcinoma by comparing the results of differential proteomic analysis between colorectal adenoma and early malignantly transformed adenoma. METHODS: Two-dimensional gel electrophoresis was used to define patterns of protein expressions of colorectal adenoma and early malignantly transformed adenoma. Proteins expressed differentially among groups were detected, cut out and analyzed by MALDI-TOF/TOF mass spectrometry. RESULTS: Two-dimensional protein maps of colorectal adenoma and early malignantly transformed adenoma were analyzed with gel-analysis software, an average of 1 672 spots in adenoma, 1 732 in early malignantly transformed adenoma were observed. 28 spots of a 1.5-fold change were found, including 15 proteins down-regulated and 13 up-regulated in early malignantly transformed adenoma, in which 23 proteins were identified by mass spectrometry, the rate of identification was 82.14%. 13 differential proteins were attained, 8 were up-regulated and 5 were down-regulated, which was classified to 6 categories, including protease inhibitor, complement, immunoglobulin, keratoproteins, signal transduction protein and function-unknown proteins. CONCLUSION: The changes of serum proteins in early malignantly transformed adenoma from adenoma can be identified by proteomic technology. Proteins detected in the study may provide new biomarkers correlated with biological behavior of colorectal adenocarcinoma.  相似文献   
208.
美王是以自交系M16为母本,以自交系W-2为父本配制而成的早熟西瓜一代杂种。露地地膜覆盖栽培,果实发育期30 d(天)左右,全生育期97 d(天)左右;日光温室秋冬茬或冬春茬栽培,果实发育期50 d(天)左右,全生育期108 d(天)左右。植株生长势中等,主蔓第6节着生第1雌花,以后每隔 2~3节现1雌花,结果能力强,田间整齐度好。果实圆球形,果皮绿色覆墨绿色规则条带,瓤大红色,剖面均匀一致,中心可溶性固形物含量11.6 %,边部 10.6 %,VC含量84 mg·kg-1,风味好,品质佳。单瓜质量3.5 kg左右,每667 m2产量3 800 kg左右,适于露地早熟栽培和保护地栽培。  相似文献   
209.
Cucumber chilling-resistant cultivar Changchun mici and -sensitive cultivar Beijing jietou were used in this study to investigate the effects of exogenous PAs on protection against chilling injury as well as on changes of physiological features, and the fluctuation of free PAs content in the leaves under chilling stress. Upon chilling treatment, free spermidine (Spd), spermine (Spm) and putrescine (Put) were remarkably induced in the leaves of cv. Changchun mici 1 day after treatment. The induction of Put declined thereafter, whereas Spd and Spm levels increased steadily. In the leaves of cv. Beijing jietou, Put content was increased only at 1 day after chilling while Spd content decreased significantly upon chilling treatment. Chilling reduced soluble protein content, and decreased the activities of antioxidant enzymes, including superoxidase dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) only in Beijing jietou. However, these changes could be renovated by exogenous application of Put and Spd. It was also found that pretreatment with Put and Spd diminished the increased electrolyte leakage and malondialdehyde (MDA) content caused by chilling in the leaves of both cultivars. Pretreatment of methyglyoxal-bis-(guanylhydrazone) (MGBG), the PAs biosynthetic inhibitor cancelled the effects of PAs in most of the treatments. Moreover, histochemical staining and quantitative measurements showed that exogenous application of Put and Spd eliminated but MGBG exaggerated the hydrogen peroxide (H2O2) accumulation caused by chilling stress, especially in leaves of Beijing jietou. Interestingly, Changchun mici was found to contain higher endogenous free PAs contents compared to Beijing jietou. While no significant difference of SOD, POD and CAT activities was found between non-chilling Changchun mici and Beijing jietou seedlings, the former exhibited higher APX activity than the latter. These results suggest that PAs play important roles in the tolerance of cucumber against chilling stress, which is most likely achieved by acting as oxidative machinery against chilling injury.  相似文献   
210.
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