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1.
林宝元  王育生 《核技术》1993,16(5):283-285
对37名骨密度(BD)低下的飞行员(实验组)和BD正常的48名飞行员、100名地面人员(正常对照组)进行了BD和血清TT_3、TT_4、TSH IRMA、CT、PTH、E_2和T放射免疫测定。结果显示,实验组BD均值明显低于对照组(p<0.01),血清TT_3、TT_4、CT、E_2(女性)和T(男性)均值与对照组比较,大多数年龄存在着显著或非常显著差异(p<0.05或p<0.01)。同时对飞行人员BD与几种内分泌激素关系进行了探讨。  相似文献   
2.
Hormone signaling plays a pivotal role in plant–microbe interactions. There are three major phytohormones in plant defense: salicylic acid (SA), jasmonic acid (JA), and ethylene (ET). The activation and trade-off of signaling between these three hormones likely determines the strength of plant defense in response to pathogens. Here, we describe the allocation of hormonal signaling in Brassica napus against the fungal pathogen Leptosphaeria maculans. Three B. napus genotypes (Westar, Surpass400, and 01-23-2-1) were inoculated with two L. maculans isolates (H75 8-1 and H77 7-2), subsequently exhibiting three levels of resistance: susceptible, intermediate, and resistant. Quantitative analyses suggest that the early activation of some SA-responsive genes, including WRKY70 and NPR1, contribute to an effective defense against L. maculans. The co-expression among factors responding to SA/ET/JA was also observed in the late stage of infection. The results of conjugated SA measurement also support that early SA activation plays a crucial role in durable resistance. Our results demonstrate the relationship between the onset patterns of certain hormone regulators and the effectiveness of the defense of B. napus against L. maculans.  相似文献   
3.
Hormone receptor expression patterns often correlate with infiltration of specific lymphocytes in tumors. Specifically, the presence of specific tumor-infiltrating lymphocytes (TILs) with particular hormone receptor expression is reportedly associated with breast cancer, however, this has not been revealed in epithelial ovarian cancer (EOC). Therefore, we investigated the association between hormone receptor expression and TILs in EOC. Here we found that ERα, AR, and GR expression increased in EOC, while PR was significantly reduced and ERβ expression showed a reduced trend compared to normal epithelium. Cluster analysis indicated poor disease-free survival (DFS) in AR+/GR+/PR+ subgroup (triple dominant group); while the Cox proportional-hazards model highlighted the triple dominant group as an independent prognostic factor for DFS. In addition, significant upregulation of FoxP3+ TILs, PD-1, and PD-L1 was observed in the triple dominant group compared to other groups. NanoString analyses further suggested that tumor necrosis factor (TNF) and/or NF-κB signaling pathways were activated with significant upregulation of RELA, MAP3K5, TNFAIP3, BCL2L1, RIPK1, TRAF2, PARP1, and AKT1 in the triple dominant EOC group. The triple dominant subgroup correlates with poor prognosis in EOC. Moreover, the TNF and/or NF-κB signaling pathways may be responsible for hormone-mediated inhibition of the immune microenvironment.  相似文献   
4.
聚乙二醇化重组人生长激素的性质及活性   总被引:1,自引:0,他引:1  
目的 研究聚乙二醇化重组人生长激素的性质及活性。方法 通过分子筛高效液相 (SizeexclusionHPLC)、毛细管等电聚焦 (CIEF)、圆二色谱 (CD)以及荧光光谱等方法检测单聚PEG- GH的纯度、等电点、二级结构以及分子构象 ;采用妊娠兔肝细胞放射受体分析法 (RRA)检测单聚PEG GH的体外受体亲和力 ,采用未成年去垂体大鼠体重增加法检测体内生物活性。结果 分子筛高效液相图谱上仅出现一个峰 ,表明样品纯度很高 ,等电点范围为 5 .1~ 5 .2 ,与未修饰的rhGH的等电点相一致 ;CD谱与荧光光谱均表明单个mPEG ALD的修饰对rhGH的二级结构以及分子构象没有明显影响 ;与未修饰的rhGH相比 ,单聚PEG GH体外受体亲和力明显降低 ;但体内作用时间更长 ,且更加有效。结论 此结果为进一步研究和开发长效重组人生长激素提供了理论依据。  相似文献   
5.
针对网络故障诊断中的模式识别问题, 提出一种基于多重提升(MultiBoost) 的优化支持向量机集成学习方法. 首先, 利用自适应的荷尔蒙调节遗传算法(HMGA), 对支持向量机基分类器进行建模参数优化; 然后, 通过构建MultiBoost 集成学习方法将多个基分类器集成, 建立以多分类器优化集成为核心的故障诊断系统. 实验结果表明, 所提出的方法在网络故障诊断中, 迭代次数少、建模时间短, 并且能够明显提高故障分类的准确率.  相似文献   
6.
为了解决多机器人系统分布式控制问题,借鉴人体内分泌系统研究的理论成果,提出基于晶格的人工内分泌系统模型.该模型以环境晶格化为基础,以细胞智能化为依托,以累加激素为纽带,以靶细胞为导向,能够适应外环境的持续变化,保持内环境的相对稳定,充分体现人体内分泌系统的自组织和自修复特性.实验结果表明,无需复杂的集中控制策略,基于该...  相似文献   
7.
周剑玲  王秀艳 《计算机工程》2010,36(10):181-183
鉴于动态r匹配算法对为了提高入侵检测系统的性能的重要性,通过研究内分泌系统对生物体内环境的调节机制,提出一个内分泌激素浓度的动态平衡模型及一种基于激素浓度调节的动态r匹配算法。仿真实验结果表明,该匹配算法能根据网络状态的变化,自适应地调整匹配参数,具有较好的匹配效果。  相似文献   
8.
《Journal of dairy science》2021,104(10):10854-10862
We studied the use of the 3 commonly used reproductive hormones, namely prostaglandins, GnRH, and progesterone, and associated herd-level factors on 760 Dutch dairy farms from 5 veterinary clinics. From 2017 to 2019 we collected data on the sales of reproductive hormones, converted this data into the number of reproductive hormone doses conducted, and expressed this as the annual number of reproductive hormone doses per 100 adult dairy cows. Additional herd-level information was available for 2019. Due to the excess of zeros in the data set (i.e., a substantial number of farms did not use any hormones), we used a zero-inflated negative binomial model to identify related herd-level factors for the use of reproductive hormones. In the entire study period of 2017 to 2019, 5.8% of the dairy farms did not use any reproductive hormones, with the proportion of nonusers varying between 0.0 and 10.3% per veterinary clinic. This proportion was around 13.5% on an annual basis. Prostaglandins were the most frequently used reproductive hormone in Dutch dairy cows (62.9%), followed by GnRH (33.1%) and progesterone (4.0%). Furthermore, participating in a veterinary herd health management program had a significant effect on reproductive hormone use. These farms used more reproductive hormones than farms that did not participate in a herd health management program and were less represented in the group of nonuser farms. Technologies, such as pedometers and automatic milking systems, also had an effect on reproductive hormone use. The presence of pedometers or activity monitors did not reduce the use of the reproductive hormones but was associated with a greater frequency of users. Farms with an automatic milking system used more reproductive hormones than farms with a conventional milking system. With this study, we have made a first step in achieving transparency in the Dutch dairy industry by providing an objective overview of reproductive hormone use on Dutch dairy farms and identifying associations with some herd-level factors.  相似文献   
9.
Using a 5-d controlled internal drug-release (CIDR)-Cosynch resynchronization protocol, the objective of this study was to determine the effect of the initial GnRH injection on pregnancy per artificial insemination (P/AI) to the second artificial insemination in lactating Holstein dairy cows. On 37 ± 3 d (mean ± standard deviation) after the first artificial insemination, and upon nonpregnancy diagnosis (d 0 of the experiment), lactating cows eligible for a second artificial insemination (n = 429) were enrolled in a 5-d CIDR-Cosynch protocol. On d 0, all cows received a CIDR insert and were assigned randomly to receive the initial GnRH injection (GnRH; n = 226) of the protocol or no-GnRH (n = 203). Blood samples were collected from a sub-group of cows (n = 184) on d 0 and analyzed for progesterone (P4) concentration. On d 5, CIDR inserts were removed, and all cows received 1 injection of PGF. On d 6 and 7, cows were observed once daily by employees for tail-chalk removal, and cows detected in estrus on d 6 or 7 received artificial insemination that day (EDAI), and did not receive the final GnRH injection. The remaining cows not detected in estrus by d 8 received GnRH and timed artificial insemination (TAI). Pregnancy status was confirmed by transrectal palpation of uterine contents at 37 ± 3 d (mean ± standard deviation) after the second artificial insemination. Eliminating the initial GnRH injection had no effect on P/AI compared with cows receiving GnRH (27 vs. 21%), respectively. Similarly, method of insemination (EDAI vs. TAI) and its interaction with treatment had no effect on P/AI. Primiparous cows had greater P/AI than multiparous cows (31 vs. 21%). Mean P4 concentrations (n = 184) at the initiation of the protocol did not differ between treatments (4.51 ± 0.35 ng/mL no-GnRH vs. 3.96 ± 0.34 ng/mL of GnRH). When P4 concentrations were categorized as high (≥1 ng/mL) or low (<1 ng/mL), P/AI tended to be greater for high P4 concentrations (n = 136) compared with low (n = 48) P4 concentrations (26 vs. 16%, respectively). No differences were observed in the proportion of cows with high or low P4 between treatments. Collectively, these results provide evidence that eliminating the initial GnRH in a 5-d CIDR-Cosynch resynchronization protocol for lactating dairy cows did not reduce P/AI in this study.  相似文献   
10.
《Journal of dairy science》2019,102(12):11597-11608
Dairy cows cope with severe energy insufficiency in early lactation by engaging in intense and sustained mobilization of fatty acids from adipose tissue. An unwanted side effect of this adaptation is excessive lipid accumulation in the liver, which in turn impairs hepatic functions. Mice experiencing increased hepatic fatty acid flux are protected from this condition through coordinated actions of the newly described hormone fibroblast growth factor-21 (FGF21) on liver and adipose tissue. The possibility of an analogous role for FGF21 in dairy cows is suggested by its rapid increase in plasma levels around parturition followed by chronically elevated levels in the first few weeks of lactation. To test this hypothesis, dairy cows were randomly assigned on d 12.6 ± 2.2 (± standard error) of lactation to receive either an excipient (control; n = 6) or recombinant human FGF21 (n = 7), first as an FGF21 bolus of 3 mg/kg of body weight (BW) followed 2 d later by a constant i.v. infusion of FGF21 at a rate of 6.3 mg/kg of metabolic BW for 9 consecutive days. After bolus administration, human FGF21 circulated with a half-life of 194 min, and its constant infusion increased total plasma concentration 117-fold over levels in excipient-infused cows. The FGF21 treatment had no effect on voluntary feed intake, milk yield, milk energy output, or net energy balance measured over the 9-d infusion or on final BW. Plasma fatty acids circulated at lower concentrations in the FGF21 group than in the control group for the 8-h period following bolus administration, but this reduction was not significant during the period of constant i.v. infusion. Treatment with FGF21 caused a 50% reduction in triglyceride content in liver biopsies taken at the end of the constant i.v. infusion without altering the mRNA abundance of key genes involved in the transport, acyl coenzyme A activation, or oxidation of fatty acids. In contrast, FGF21 treatment ablated the recovery of plasma insulin-like growth factor-1 seen in control cows during the 9-d i.v. infusion period despite a tendency for higher plasma growth hormone. This effect was associated with increased hepatic mRNA abundance of the intracellular inhibitor of growth hormone receptor trafficking, LEPROT. Overall, these data confirm the ability of FGF21 to reduce lipid accumulation in bovine liver and suggest the possibility that FGF21 does so by attenuating the hepatic influx of adipose tissue-derived fatty acids.  相似文献   
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