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11.
The metabolism of 52–73-day old Antarctic fur seal pups from Bird Island, South Georgia, was investigated during fasting periods of normal duration while their mothers were at sea foraging. Body mass decreased exponentially with pups losing 3.5–3.8% of body mass per day. Resting metabolic rate also decreased exponentially from 172–197 ml (O2)·min−1 at the beginning of the fast and scaled to Mb0.74 at 2.3 times the level predicted for adult terrestrial mammals of similar size. While there was no significant sex difference in RMR, female pups had significantly higher (F1,18=6.614, P<0.019) mass-specific RMR than male pups throughout the fasting period. Fasting FMR was also significantly (t15=2.37, P<0.035) greater in females (823 kJ·kg−1·d−1) than males (686 kJ·kg−1·d−1). Average protein turnover during the study period was 19.3 g·d−1 and contributed to 5.4% of total energy expenditure, indicating the adoption of a protein-sparing strategy with a reliance on primarily lipid catabolism for metabolic energy. This is supported by observed decreases in plasma BUN, U/C, glucose and triglyceride concentrations, and an increase in β-HBA concentration, indicating that Antarctic fur seals pups adopt this strategy within 2–3 days of fasting. Mean RQ also decreased from 0.77 to 0.72 within 3 days of fasting, further supporting a rapid commencement of protein-sparing. However, RQ gradually increased thereafter to 0.77, suggesting a resumption of protein catabolism which was not substantiated by changes in plasma metabolites. Female pups had higher TBL (%) than males for any given mass, which is consistent with previous findings in this and other fur seal species, and suggests sex differences in metabolic fuel use. The observed changes in plasma metabolites and protein turnover, however, do not support this.  相似文献   
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目的 了解TORCH感染情况,为妇幼保健提供参考依据.方法 采用捕获ELISA方法对1 253例孕妇和新生儿的血清进行TORCH-IgM抗体检测.结果 689例孕妇CMV、TOX、RV及HSVⅡ特异性IgM抗体阳性率分别为1.89%、0.87%、0.44%和0.73%;564例新生儿CMV-IgM、TOX-IgM、RV-IgM和HSVⅡ-IgM阳性率分别为6.91%、0.18%、0和0.35%.结论 检测TORCH特异性抗体对优生优育有重要关系.  相似文献   
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Operant generalization has been demonstrated in neonates only recently. To investigate the development of intradimensional stimulus control immediately after hatching, northern bobwhite chicks (Colinus virginianus) pecked for brief heat presentations while hearing a high-pitched sound repeated at two constant rates: an S+ tempo signaling a rich reinforcement schedule, alternating with an S− tempo signaling a leaner schedule. Tempo generalization was then assessed in extinction. The expected excitatory gradients were produced after a threshold number of training sessions; unexpectedly, below that threshold, gradients were inhibitory. The chicks’ rapidly developing thermoregulatory capability may have resulted in a change from perceived negative reinforcement initially to positive reinforcement later. Given past research showing excitatory gradients after negative reinforcement, we suggest that these results demonstrate that all negative reinforcement is not equivalent, and, further, that classical conditioning effects require consideration.  相似文献   
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目的:评价脑脊液检查在早产儿及足月儿细菌性脑膜炎诊断中的价值。方法:选取2014年6月1日至2016年12月31日上海市儿童医院新生儿科收治的行腰椎穿刺检查的447例新生儿,回顾性分析新生儿的一般资料、脑脊液常规生化、培养等指标,根据胎龄将患儿分为早产儿167例与足月儿280例,再根据有无患发细菌性脑膜炎分为早产儿细菌性脑膜炎27例(早产儿观察组)、早产儿非细菌性脑膜炎140例(早产儿对照组)、足月儿细菌性脑膜炎38例(足月儿观察组)、足月儿非细菌性脑膜炎242例(足月儿对照组),采用受试者工作特征(ROC)曲线评估蛋白定量、白细胞计数、葡萄糖对早产儿及足月儿细菌性脑膜炎的诊断价值。结果:与同组对照组相比,足月儿观察组和早产儿观察组蛋白定量和白细胞计数均明显升高,而葡萄糖含量显著下降,且差异均具有统计学意义(P0.05);本研究65例细菌性脑膜炎患儿脑脊液培养分离出11株细菌(16.9%)。足月儿脑脊液白细胞计数、蛋白定量以及葡萄糖诊断细菌性脑膜炎的ROC曲线下面积分别为0.995、0.846、0.703。早产儿脑脊液白细胞计数、蛋白定量以及葡萄糖诊断细菌性脑膜炎ROC曲线下面积分别为0.970、0.711、0.705。结论:脑脊液白细胞计数、蛋白定量在足月儿和早产儿细菌性脑膜炎中具有较高的诊断价值。  相似文献   
15.
The effect of the larger molecular weight l-amino acids on the development of spleen explants from 1- and 21-day rats in organotypic tissue culture was studied. The amino acids asparagine, lysine, arginine, and glutamic acid inhibited the growth zone of explants of immature tissue from 1-day animals but had an opposite, stimulating, effect on mature spleen tissue of 21-day rats. Immunohistochemical analysis revealed a reciprocal correlation between the expression of the proapoptotic protein, p53, and T-cell proliferation in response to lysine, asparagine, and glutamic acid. Interestingly only arginine reduced the area of p53 expression both in explants of mature and immature spleen tissue. The ability of arginine to reduce p53 expression can be suggested as one of the mechanisms of the tumor growth stimulation.  相似文献   
16.
摘要 目的:探讨与分析高胆红素血症新生儿肠道菌群特点与苯巴比妥治疗效果的相关性。方法:选择2020年6月到2022年6月在本院诊治的565例高胆红素血症新生儿作为研究对象,所有患儿都给予苯巴比妥治疗,检测新生儿肠道菌群与血清α-谷胱甘肽-s-转移酶(α-GST)、肌酸激酶同工酶(CK-MB)、胆红素含量,判定患儿的治疗效果并进行相关性分析。结果:565例患儿治疗7 d后,有效490例(有效组),有效率为86.7 %。有效组的血清胆红素、经皮胆红素含量都明显低于无效组(P<0.05)。有效组的血清α-GST、CK-MB含量都明显低于无效组(P<0.05)。有效组的肠球菌属、埃希氏菌属、链球菌属相对丰度均低于无效组,拟杆菌属相对丰度明显高于无效组(P<0.05)。在565例患儿中,Spearsman分析显示苯巴比妥治疗效果有效与肠球菌属、埃希氏菌属、链球菌属、拟杆菌属相对丰度都呈现相关性(P<0.05)。结论:苯巴比妥治疗新生儿高胆红素血症的效果有待提高,通过胆红素、α-GST、CK-MB、肠道菌群检测能有效判定患儿的治疗效果,同时肠道菌群与治疗效果存在相关性。  相似文献   
17.
Blood chemistry and hematology were examined in 238 Steller sea lion pups (Eumetopias jubatus) to assess the health status of pups <1 month of age. Failure of juvenile recruitment (possibly due to nutritionally or physiologically compromised pups) into breeding populations has been proposed as a cause of recent declines of this endangered species in Alaska. To identify potential correlations with areas of high population decline, blood chemistry data were considered for three areas: eastern Aleutian Islands (low rates of population decline to stable populations), Gulf of Alaska (high rates of decline), and Southeast Alaska (stable to increasing population). Southeast Alaska pups showed elevated ketone body concentrations (β-hydroxybutyrate, (β-HBA)) and depressed glucose levels when compared with animals from the Aleutian Islands and lower blood urea nitrogen (BUN) and glucose levels than pups in the Gulf of Alaska. Over 40% of the pups from Southeast Alaska had elevated β-HBA concentrations suggesting they underwent longer periods of fasting than seen in pups from other areas. Hematocrit (Hct), hemoglobin concentration (Hb) and water content of the blood exhibited typical mammalian relationships. In summary, blood chemistry and hematology data showed no indication that Steller sea lion pups <1 month old from areas of population decline were nutritionally compromised.  相似文献   
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摘要 目的:研究不同病情高胆红素血症新生儿血清谷草转氨酶(AST)、胰岛素样生长因子-1(IGF-1)、神经元特异性烯纯化酶(NSE)、胱抑素C(CysC)水平的表达及临床意义。方法:将我院从2017年1月~2018年12月收治的高胆红素血症新生儿316例作为研究组。按其病情分成轻度组152例、中度组105例以及重度组59例,另取同期健康新生儿100例作为对照组。比较四组新生儿血清AST、IGF-1、NSE、CysC、总胆红素(TSB)水平,分析上述各项指标的关系。此外,比较对照组与研究组的基线资料,分析新生儿高胆红素血症发病的影响因素。结果:轻度组、中度组、重度组血清AST、IGF-1、NSE、CysC、TSB水平均高于对照组,且中度组、重度组上述指标高于轻度组,重度组上述指标高于中度组(P<0.05)。经Pearson相关性分析可得:高胆红素血症新生儿TSB水平与血清AST、IGF-1、NSE、CysC水平均呈正相关(P<0.05)。研究组和对照组在母婴血型不合、产前使用催产素、围生期疾病以及TSB、AST、IGF-1、NSE、CysC方面对比差异均有统计学意义(P<0.05)。经多因素Logistic回归分析可得:新生儿高胆红素血症发病的影响因素为产前使用催产素、围生期疾病以及TSB、AST、IGF-1、NSE、CysC(P<0.05)。结论:随着高胆红素血症新生儿病情的加剧,血清AST、IGF-1、NSE、CysC水平均逐渐升高且均与血清TSB水平呈正相关,临床工作中可能通过联合检测上述血清学指标辅助评估高胆红素血症新生儿病情,且以上指标水平的升高会增加新生儿高胆红素血症的发病风险。  相似文献   
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