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11.
The melanomacrophage aggregates or cells (MMC) are commonly used as biomarkers of exposure to pollution in fish, albeit their numbers and morphological characteristics can be influenced not only by environmental toxins but also by a range of physiological parameters and pathological conditions. Accordingly, before we can use MMC as biomarkers in any fish species, their normal, 'background' characteristics have to be established in apparently healthy fish. The knowledge of MMC in sharks is minimal. The aim of this study was to characterize MMC from 51 free-ranging, large pelagic sharks from the northwestern Atlantic, including shortfin mako, Isurus oxyrhinchus , thresher, Alopias vulpinus and blue shark, Prionacae glauca . The rationale of this study was twofold. First, because, sharks have life histories predisposing them to the accumulation of environmental toxins they constitute good sentinel species of the health of the global marine ecosystem. Second, because many shark populations are in decline or threatened by extinction, we need to expand our understanding of their health status in order to develop appropriate protective measures. All sharks were collected by sports fishing gear between June and August in 2007. Their health condition was assessed by necropsy, morphometrics, and by microscopic examination of gonads, livers, spleens and kidneys. Routine, haematoxylin and eosin and/or Pearl's reagent-stained paraffin embedded sections were studied by light microscopy. Our results provide the first data on the morphometric and morphological characteristics of MMC in viscera of apparently healthy free-ranging sharks from the northwestern Atlantic.  相似文献   
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Background

Neutrophil gelatinase–associated lipocalin (NGAL) is released from renal tubular cells after injury and serves in humans as a real‐time indicator of active kidney damage, including acute kidney injury (AKI) and chronic kidney disease (CKD). However, NGAL concentrations in dogs with naturally occurring AKI or CKD rarely have been explored in detail.

Hypothesis/Objectives

The goal of this study was to evaluate whether NGAL can serve as a useful biomarker in dogs with naturally occurring renal disease.

Animals

Client‐owned dogs with renal disease (57) and control dogs without any disease (12) were examined.

Methods

Serum NGAL (sNGAL) and urine NGAL (uNGAL) concentrations were measured in each animal by a newly developed ELISA system. Demographic, hematologic, and serum biochemical data were recorded. Survival attributable to AKI and CKD was evaluated at 30 days and 90 days, respectively.

Results

Serum and urine NGAL concentrations in azotemic dogs were significantly higher than in nonazotemic dogs and were highly correlated with serum creatinine concentration (< .05). Among CKD dogs, death was associated with significantly higher sNGAL and uNGAL concentrations compared with survivors. Receiver‐operating characteristic curve (ROC) analysis showed that sNGAL was better than serum creatinine concentration when predicting clinical outcomes for CKD dogs (< .05). The best cutoff point for sNGAL was 50.6 ng/mL, which gave a sensitivity and a specificity of 76.9 and 100%, respectively. Furthermore, dogs that had higher concentrations of sNGAL survived for a significantly shorter time.

Conclusion

sNGAL is a useful prognostic marker when evaluating dogs with CKD.  相似文献   
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The aim of the present study was to investigate the long-term effect of using bee venom (BV) on the reproductive performance, immune, and health status of rabbit does and its effect on their litters. Sixty mature does, from Spanish V-line rabbit stock, were randomly assigned to four homogeneous groups with 15 does each. The 1st, 2nd and 3rd groups were injected twice weekly under the neck skin with 0.1 ml solution contains 0.1, 0.2 and 0.3 mg BV/rabbit respectively. The 4th group served as a control group. From the results, litter size at birth, litter weight and survival rate at weaning age as well as milk yield were significantly (≤ 0.05) increased in BV groups than in the control group. Serum estradiol 17-β (E2) was significantly (≤ 0.05) higher (15%) in the rabbit does treated with BV compared to the control group. The treated does with BV at any study doses showed a gradual and significant (≤ 0.05) decrease (12%) in serum progesterone levels (P4) compared to the control. They also showed a significant (p≤0.05) increase in conception (17%) and fertility rates (10%) compared to the control does. Treatment of rabbit does with BV caused a gradual and significant (≤ 0.05) reduction in both aspartate aminotransferase (AST) (16%) and alanine aminotransferase (ALT) (37%) liver enzyme activities. Additionally, results have shown that BV resulted in a gradual and significant (≤ 0.05) increase in total antioxidant capacity (TAC), antioxidative enzymes such as glutathione S-transferase (GST) and glutathione peroxidase (GPx), serum IgG, IgM and IgA levels with significant (≤ 0.05) decrease in malondialdehyde (MDA) and thiobarbituric acid reactive substances (TBARS) in BV groups compared to the control group. Results suggest that BV can be used in rabbit farming as an effective and safe alternative to artificial chemical drugs (sexual-stimulants) to improve certain reproductive traits, immune response and health.  相似文献   
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罗芳  陶金忠 《畜牧兽医学报》2021,52(11):3118-3125
旨在筛选人工授精后第17天奶牛在不同妊娠状态时的候选生物标志物。本研究以宁夏某奶牛场体重为(550±50) kg,体况评分相近的经产(2~3胎次)健康荷斯坦奶牛为试验对象。同期发情后,在人工授精后第17天晨饲前对奶牛进行尾静脉采血,后期采用计步器和B超仪诊断出奶牛的妊娠状态。根据诊断结果将奶牛分为妊娠组(A组,n=12)和未妊娠返情组(B组,n=24),将这两组血样进行代谢轮廓及代谢物变化分析。主成分分析(PCA)和正交偏最小二乘法-判别分析(OPLS-DA)结果显示,A、B两组血浆代谢轮廓均发生了明显变化,A、B两组之间共检测出8种ROC (Receiver operating characteristic curve)曲线下面积(area under the ROC curve,AUC)>0.8的差异代谢物。丙氨酸-亮氨酸、甘氨酸、脯氨酸、L-正亮氨酸、DL-苯丙氨酸、肌氨酸、吡咯-2-羧酸和缬氨酸-蛋氨酸有望成为识别妊娠组(A组)和未妊娠返情组(B组)的差异代谢物。综上表明,血浆中的这8种代谢物有望成为奶牛妊娠识别阶段潜在的生物标志物,为配种早期妊娠识别提供新思路。  相似文献   
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采用定量气相色谱质谱技术,剖析了天2井原油的生物标志物组合特征并追踪了其油源。研究结果表明,天2井原油中C31-C35藿烷丰度依次降低,含有较高丰度的伽马蜡烷,无重排藿烷和重排甾烷,C27-C29规则甾烷呈反“L”型分布,C28甾烷丰度较高。甾烷的异构化成熟度参数、甲基菲指数均暗示原油成熟度低。在对本区可能烃源岩生物标志物组合特征广泛调查的基础上,从生物标志物指纹和绝对浓度特征确认了天2井原油与下白垩统巴音戈壁组下段烃源岩有成因联系,指出巴音戈壁组下段烃源岩为天草凹陷主力烃源岩。  相似文献   
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Precipitation and topsoil samples from a climate transect over the Scandinavian Mountains, Norway, were analyzed for bulk and compound‐specific δ18O values. The natural abundance of 18O in the plant‐derived hemicellulose biomarkers arabinose and xylose correlates positively with δ18O of bulk soil, but not with δ18O of precipitation. This suggests that other factors than δ18Oprec, such as evaporative 18O enrichment of leaf water, exert a strong influence on the natural abundance of 18O in soils.  相似文献   
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