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71.
本文综述甲状腺激素相关研究的进展 ,探讨碘在甲状腺激素与细胞内激素受体蛋白结合中的结构作用。文中评述了关于甲状腺激素与血浆运载蛋白和细胞内受体蛋白结合的溶液亲合性、结构研究和甲状腺激素碘代酚环的分子识别特性与碘的结构效应模拟研究的数据结果 ,并就碘对激素 受体蛋白结合的结构作用提出了作者的观点 相似文献
72.
Site‐Selective and Metal‐Free Aliphatic CH Oxidation Enabled Synthesis of [5,24,25‐D3]‐(25S)‐Δ7‐Dafachronic acid
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Weilong Liu Xiangke Li Jie Chen Tiemei Li Prof.Dr. Mengqiu Dong Prof.Dr. Xiaoguang Lei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5345-5349
Steroid hormones play significant roles in both worms and mammalians. (25S)‐Δ7‐Dafachronic acid (Δ7‐DA, 1 ) is a member of the dafachronic acid hormonal series that regulates both development and lifespan of C. elegans. Despite its importance, effective tools for the illumination of its mode of action are lacking. Herein, we report an efficient synthesis of trideuterated Δ7‐DA, [5,24,25‐D3]‐(25S)‐Δ7‐dafachronic acid ([D3]‐Δ7‐DA, 2 ), as a useful chemical tool for subsequent biological studies. Key steps for this bioinspired synthesis approach include site‐selective aliphatic C?H oxidation mediated by methyl(trifluoromethyl)dioxirane (TFDO), and the iridium/phosphine‐oxazoline‐catalyzed late‐stage asymmetric deuterium reduction. 相似文献
73.
74.
Mateusz Dako Anna Doga Magdalena Siedzielnik Karol Biernacki Olga Ciupak Janusz Rachon Sebastian Demkowicz 《Molecules (Basel, Switzerland)》2021,26(13)
Herein, we present the synthesis and crystal structures determination of five 4-(1-phenyl-1H-1,2,3-triazol-4-yl)phenol derivatives containing halogen atoms, 6a–e, which may be used as an excellent mimic of steroids in the drug development process. Good quality crystals obtained for all of the synthesized compounds allowed the analysis of their molecular structures. Subsequently, the determined crystal structures were used to calculate the Hirshfeld surfaces for each of the synthesized compounds. Furthermore, results of our docking studies indicated that synthesized derivatives are able to bind effectively to the active sites of selected enzymes and receptors involved in the hormone biosynthesis and signaling pathways, analogously to the native steroids. 相似文献
75.
76.
淇河鲫生长激素(growth hormone)全长cDNA的克隆与序列分析 总被引:1,自引:0,他引:1
用RT-PCR法和3′、5′RACE(Rapid amplification of cDNAends)法从淇河鲫脑垂体RNA克隆出生长激素(Growth hormone,GH)cDNA.此cDNA全长1191 nt(含Poly(A)14 nt),其5′端非编码区长55 nt、阅读框(Open readingframe,OAF)长633 nt,3′端非编码区长503 nt.其推导的GH由210个氨基酸组成,其中氮端前22个氨基酸为信号肽部分.氨基酸序列比较表明:淇河鲫与同目的鲫鱼、鲤鱼、团头鲂和斑马鱼的同源性分别为98.6%,96.2%,91.5%和88.6%;与不同目鱼的胡子鲇和鳗鲡的同源性分别为74.6%和49.5%;与哺乳类的家鼠和人等的同源性低于40%. 相似文献
77.
建立了准确、快速测定痕量人体生长激素的同位素稀释质谱法。选取同位素标记脯氨酸、缬氨酸和苯丙氨酸为内标物,将内标物以重量法与待测样品准确混合,利用Kinetex C18色谱柱分离,以电喷雾三重串联四级杆质谱多反应监测模式测定,建立了人体生长激素的液相色谱–同位素稀释质谱联用定量方法。人体生长激素溶液标准物质的含量测定结果为(1.82±0.04)mg/g,相对标准偏差为0.43%(n=6)。该方法简易、实用、准确、可靠,可作为人体生长激素溶液标准物质的定值方法,并为人体生长激素的日常检测提供参考。 相似文献
78.
Solution-enhanced dispersion by supercritical fluids (SEDS) was applied to produce nano-sized recombinant human growth hormone
(hGH) particles. Ethanol was used to help the supercritical carbon dioxide to extract water from the aqueous protein solution.
Various sizes of hGH nanoparticles were successfully prepared with a narrow particle size distribution from aqueous ethanol
solution without using any additive. The theoretical particle sizes were deduced from the calculated droplet sizes based on
a modified Jasuja’s equation. The calculated mean particle sizes and the experimentally obtained ones were compared and the
results showed an excellent correlation coefficient (R
2) of 0.995.
Figure Distribution of hGH Nano-particles 相似文献
79.
Leonie A. Menke Theo C.J. Sas Sophie H.L. van Koningsbrugge Maria A.J. de Ridder Gladys R.J. Zandwijken Bart Boersma Philippe H. Dejonckere Sabine M.P.F. de Muinck Keizer-Schrama Barto J. Otten Jan M. Wit 《Journal of voice》2011,25(5):602-610
Objectives/Hypothesis
Oxandrolone (Ox) increases height gain but may also cause voice deepening in growth hormone (GH)-treated girls with Turner syndrome (TS). We assessed the effect of Ox on objective and subjective speaking voice frequency in GH-treated girls with TS.Study Design
A multicenter, randomized, placebo (Pl)-controlled, double-blind study was conducted.Methods
One hundred thirty-three patients were included and treated with GH (1.33 mg/m2/d) from baseline, combined with Pl or Ox in a low (0.03 mg/kg/d) or conventional (0.06 mg/kg/d) dose from the age of 8 years and estrogens from the age of 12 years. Yearly from starting Ox/Pl until 6 months after discontinuing GH + Ox/Pl, voices were recorded and questionnaires were completed.Results
At start, mean (±standard deviation [SD]) voice frequency SD score (SDS) was high for age (1.0 ± 1.2, P < 0.001) but normal for height. Compared with GH + Pl, voices tended to lower on GH + Ox 0.03 (P = 0.09) and significantly lowered on GH + Ox 0.06 (P = 0.007). At the last measurement, voice frequency SDS was still relatively high in GH + Pl group (0.6 ± 0.7, P = 0.002) but similar to healthy girls in both GH + Ox groups. Voice frequency became lower than −2 SDS in one patient (3%) on GH + Ox 0.03 and three patients (11%) on GH + Ox 0.06. The percentage of patients reporting subjective voice deepening was similar between the dosage groups.Conclusions
Untreated girls with TS have relatively high-pitched voices. The addition of Ox to GH decreases voice frequency in a dose-dependent way. Although most voice frequencies remain within the normal range, they may occasionally become lower than −2 SDS, especially on GH + Ox 0.06 mg/kg/d. 相似文献80.