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人绒毛膜促性腺激素激发试验在性发育异常儿童中的诊断作用评估

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中国当代儿科杂志 2024年第2期26卷 158-163页

作者：梁翠丽刘国昌程静牛会林伏雯张丽瑜贾炜张文刘丽广州医科大学附属广州市妇女儿童医疗中心遗传与内分泌科广东广州510623 广州医科大学附属广州市妇女儿童医疗中心泌尿外科广东广州510623 广州医科大学附属广州市妇女儿童医疗中心病理科广东广州510623

目的探讨人绒毛膜促性腺激素(human chorionic gonadotrophin,hCG)激发试验在诊断不同分型性发育异常(disorder of sexual development,DSD)患儿中的价值。方法回顾性分析132例DSD患儿,按染色体核型分为46,XX组(n=10)、46,xy组(n=87)、性染色体异常组(n=35),比较各组患儿hCG激发试验前后的性激素水平,分析形态学上是否存在睾丸组织对hCG激发试验结果的影响。结果3组患儿激发试验后睾酮(testosterone,T)增加倍数比较差异无统计学意义(P>0.05)。46,xy组中,5α-还原酶2缺乏症患儿激发试验后的T与双氢睾酮(dihydrotestosterone,DHT)比值高于其他46,xy DSD患儿(P<0.05)。形态学上,有睾丸组织的DSD患儿激发试验后T增加倍数高于无睾丸组织患儿(P<0.05)。结论hCG激发试验对于评估不同类型的DSD患儿的睾丸间质细胞存在和功能均具有重要价值,对于性腺性质不明确的DSD患儿,均建议行hCG激发试验。

关键词：性发育异常人绒毛膜促性腺激素激发试验睾丸间质细胞睾酮儿童

Syntheses of New Crowned Indolinospirobenzopyrans

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Chinese Chemical Letters 1997年第4期8卷 285-288页

作者： Wu, xy Wu, CT WUHAN UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

Two new indolinospirobenzopyrans bearing monoaza-benzo-15-C-5 were synthesized. And they were determined by IR, H-1 NMR and MS.

关键词： RECOGNITION INDUCED ISOMERIZATION SPIROBENZOPYRANS

12-Deoxyphorbol Esters from Euphorbia Fischeriana

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Chinese Chemical Letters 1996年第10期7卷 917-918页

作者： liu, WZ Wu, xy Yang, GJ Ma, QG Zhou, TX Tang, XC Qin, GW SUN YAT SEN UNIV MED SCI DEPT CHEM GUANGZHOU 510089 PEOPLES R CHINA CHINESE ACAD SCI SHANGHAI INST MAT MED SHANGHAI 200031 PEOPLES R CHINA Second Mil Med Univ SCH PHARM SHANGHAI 200433 PEOPLES R CHINA

Two compounds, 12-deoxyphorbol-13-hexadecanoate 1 and 12-deoxyphorbol-13-acetate 2 were isolated from the roots of Euphorbia fischeriana. Compoound 1 was elucidated as a new diterpenoid. Compound 2 was discovered for ... 详细信息

关键词： Deoxyphorbol Esters from Euphorbia Fischeriana

Spectroscopic studies on interaction of hemoglobin and serum albumin with nicotine

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Chinese Science Bulletin 2002年第7期47卷 538-542页

作者： Wang, HF Wang, Y Cheng, Y Sun, HF Wang, xy liu, YF Peking Univ Coll Chem & Mol Engn Dept Appl Chem Beijing 100871 Peoples R China

The interactions of nicotine and Hb/SA were studied in vitro by UV/Vis, fluorescence, 1H NMR and FT-IR spectroscopies. The UV/Vis absorbance of Hb/SA (200nm) shifted to red and decreased gradually with the addition of nicotine, indicating that the protein conformational change resulted from the chemical interaction. With increasing nicotine concentration, incubation of SA with nicotine caused the quenching of fluorescence typical of protein tryptophan residues, which meant that the vicinity of the tryptophan residues of SA was changed because of nicotine. FT-IR spectra showed that α-helix component of Hb/SA decreased, turn and β-structure components of Hb/SA increased in the presence of nicotine. In the 1H NMR spectra of nicotine, all proton peaks on pyrrolidinyl ring moved to downfield and the resonance emanating from nicotine was preferentially broadened while the concentration of Hb/SA increased. All these results indicate that nicotine and Hb/SA in vitro interact on each other, forming a new

关键词： hemoglobin (Hb) serum albumin (SA) nicotine spec-troscopic studies.

Construction of human combinatorial antibody library and screening of monoclonal antibody Fabs to human immunodeficiency virus type Ⅰ

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Chinese Science Bulletin 1999年第4期44卷 352-356页

作者： Wang, X He, YX Zhou, Y liu, S Yan, xy Tien, P Chinese Acad Sci Inst Microbiol Beijing 100080 Peoples R China Beijing Ditan Hosp Dept Virol Beijing 100011 Peoples R China

The heavy chain Fd genes and K chain genes of immunoglobulin were amplified by RT-PCR from PBL of three volunteer donors with HIV-positive. Phage antibody library was constructed with the Fd genes and K chain genes using pComb3 as vector. Three-round selection against coated gpl20 showed specific enrichment of phage antibodies. After the third round selection, 40 out of 50 clones exhibited gpl20 binding capacity. The specificity of the clones was verified by ELISA and competition inhibition ELISA. The V_H was derived from subgroups V_Ⅱ and V_Ⅲ, V_L belonged to subgroups V_K Ⅰ and V_K Ⅲ with DNA sequencing. These results suggest that the antibodies obtained are specific to gpi20.

关键词： immunoglobulin combinatorial library phage antibody Fab gp120 HIV-1.

Sealing Interfaces of Pin in Colour Picture Tube

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Journal of Materials Science & Technology 1996年第1期12卷 78-80页

作者： Wang, GQ Tang, xy Ma, JS Dept. of Materials Science and Engineering Tsinghua University Beijing 100084 China

interfacial geometric morphology, chemistry and microstructure have been studied by SEM, EDAX, HREM, and XPS. It is found that the oxide scale/metal interface consists of two layers. The first one is amorphous SiO2 growing inward metal matrix, and the second one under the first layer is TiO2 distributing in metal matrix. There is microstructural transition zone at Cr2O3/SiO2 interface, and an atomic mixed zone with 8 nm width at SiO2/metal interface. The transition zone which is saturated with Cr diffusing from oxide scale exists at the oxide scale/glass interface. The reasons why sand-blasting process can improve bonding strength of the oxide scale and the metal are also discussed. The ideal interfaces are proposed finally.

关键词： Television picture tubes

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多情景下张家口市土地利用变化及碳储量分析

环境科学与技术 2024年第6期47卷 200-212页

作者：罗义刘伟强董一凡王霞刘文焕宋锦阳河北建筑工程学院市政与环境系河北张家口075132 伊犁师范大学物理科学与技术学院新疆伊宁835000

土地利用改变促进生态系统碳储量变化,进而对全球气候产生影响,研究土地利用变化对碳储量的影响,对区域生态系统和实现经济可持续发展具有重要意义。该研究以张家口市为例,基于2000年、2010年和2020年土地利用数据,结合PLUS模型和InVES... 详细信息

土地利用改变促进生态系统碳储量变化,进而对全球气候产生影响,研究土地利用变化对碳储量的影响,对区域生态系统和实现经济可持续发展具有重要意义。该研究以张家口市为例,基于2000年、2010年和2020年土地利用数据,结合PLUS模型和InVEST模型分析土地利用变化与碳储量的关系并对未来不同情景下的碳储量进行评估。结果表明:(1)张家口市土地利用类型以耕地和草地为主,占该地区总面积约71%。20年间,耕地和草地面积呈下降趋势,林地、建设用地面积呈现增长态势,其主要转换方向为耕地转为建设用地。(2)2030年,自然发展情景下,耕地、林地、水域均有所下降,草地、建设用地和未利用地有所增长;生态保护情景下,林地和草地相较自然发展有所增加,其余地类均有不同程度的减少;耕地保护情景下,耕地面积相较于自然发展情景增加约1.11 km^(2)。(3)过去20年间,该区域碳储量先上升后下降,但总体碳储量依然呈现下降趋势,年均下降0.19×10^(6)t;2030年自然发展情景下,碳储量为766.43×10^(6)t;耕地保护情景下,碳储量为767.28×10^(6)t;生态保护情景下,碳储量为768.5×10^(6)t。耕地保护碳储量介于自然发展和生态保护之间,因此张家口市在未来发展中应实行耕地优先发展前提下采取一定生态保护措施,以减缓碳储量下降速率。

关键词：土地利用结构变化 PLUS模型 InVEST模型碳储量张家口市

Characterization of Nanocrystalline Intermetallic Compound NiAl Synthesized by Condensation

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Journal of Materials Science & Technology 1996年第6期12卷 461-463页

作者： Qin, Y Qin, xy Zhang, LD Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

Nanocrystalline intermetallic compound NiAl was synthesized by evaporating NiAl master alloy in inert-gas followed by in situ compaction, and its structure was studied by means of X-ray diffractometry and transmission electron microscope. Experimental results reveal that the as-synthesized nanocrystalline sample has a mean grain size of less than 10 nm and it is dominantly composed of the cubic structure phase NiAl. However, nanocrystalline Ni3Al as a trace phase mixed in NiAl phase, was also detected by transmission electron microscope observation.

关键词： Intermetallics

Research on Water-Taking Characteristics of Huanghua Power Plant Reach

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China Ocean Engineering 1998年第1期13卷 99-112页

作者： Tong, ZS Ying, xy Qian, BF Nanjing Hydraul Res Inst Dept Hydraul Engn Nanjing 210029 Peoples R China

In this paper the water-taking characteristics of the first,the second and the third stage of theHuanghua Power Plant are studied by numerical model and physical *** results show that the pres-ent inlet channel only satisfies the supply need of the first stage of the power *** the riverbed of the in-let reach is properly dredged,the need of water supply for the third stage of the power plant could be met.

关键词： physical model numerical simulation cooling water tidal river