铅在人体中的允许量及其与锌的相关性

236名健康人按年龄分6组统计，发铅值（x±S）为8．98×10－6±4．95×10－6~25.66×10－6±14．16×10-6；高锌及低锌儿童共69例的发铅、发锌相关系数r＝-0．2849，呈负相关，P＜0．01。     

葡萄糖酸锌治疗3～7岁缺锌儿童疗效观察

检测了玉林市城区八所幼儿园3280名3～7岁儿童发锌。对检出发锌＜110×10-6及生长发育迟缓、厌食、头发稀黄、营养不良等1725人采用口服葡萄糖酸锌治疗（1mg／kg体重·d，分两次饭后服，连服2个月）。治疗后总有效率为95．65％，无效占4．35％，防治后发锌由原来的87．2×10－6±34．6×10-6上升为115．3×10-6±43．6×10-6，差异非常显著（P＜0．001）。     

微量元素与妊娠及围产医学的关系

为探讨微量元素与妊娠及围产医学的关系，取４９例正常孕产妇和５１例异常孕产妇的头发进行微量元素检测．结果表明，异常孕产妇中妊娠高血压综合征组发锌均值（１０４±１７．５４）×１０－６明显低于正常组（１６８±２２．１２）×１０－６，而发铜均值（１３．３±０．７８）×１０－６明显高于正常组（１１．３±０．９４）×１０－６，不明原因流产组发锌（１１５±１０．３２）×１０－６，发铜（９．０３±１．０３）×１０－６两项均值明显低于正常组，羊膜早破组仅发铜均值（７．５９±１．９７）×１０－６低于正常组；畸胎组则锌、铜、铁、钙均值都低于正常组．经统计学处理均有显著性差异（Ｐ＜０．０５或产＜０．０１）     

深圳市小学生头发中锌,铜,铁含量与血红蛋白的相关分析

为探讨深圳市小学生头发中锌、铜、铁的含量与贫血的关系，随机选择了9～14岁的小学51名，检测了头发中锌、铜、铁的含量，血红蛋白（Hb）水平，结果显示：深圳市小学生发锌、铜、铁均值分别为155．43×10-6，7．03×10-6，17．63×10-6，发锌值处于国内部分城市的较高水平，发铜含量较低，发铁居中。结合该51名小学生Hb的测定，按我国儿童少年贫血筛检国家标准，贫血29名，发锌均值为150．94×10-6；血红蛋白含量正常22名．其发锌均值为168．98×10-6，贫血组和正常组发锌含量的显著性检验t＝2．035，P＜0．05，两组发锌含量差别有显著意义，说明贫血与发锌含量有联系。在锌的日膳食供给量（RDA）基本正常的情况下，则应注意贫血和体内钢、铁含量及其利用率的相互关系。     

714名0～6岁儿童头发中6种微量元素含量及水平分析

报道了南山区714名0～6岁儿童头发中锌、铜、铁、钙、镁和锰的含量，发锌79．88×10－6、发铜9．64×10－6、发铁31．36×10－6、发钙560．54×10－6、发镁为66．12×10－6、发锰为2．24×10－6，并对分析数据进行了医学统计分析，结果表明各年龄组间、性别间无显著性差异。     

儿童发铅与智商关系的研究

为探讨环境中低浓度铅对儿童智商的影响，选择131名合肥市某小学四年级学生，以其发铅水平作为铅暴露指标，智商为效应指标。结果发现：131名儿童发铅值水平在0．05×10－6～8．35×10-6（均数上标准差为2．57×10－6±1．87±10-6，拟和智商（FIQ）水平在72～135（均数±标准差为105．27±12．68）。以3．5×10-6和1．5×10－6发铅值为分界线进行t检验，结果发现，发铅值在较低水平时（1．5×10－6）时，仍对智商有影响（P＜0．05）。控制11个对智商有影响的混杂因素后，经多元逐步回归分析，发铅值排在11个影响因素中的第2位。     

深圳市儿童发锌含量的分析研究

报道了深圳市988名1－7岁儿童头发中的锌平均值为79．88±21．88（×10-6）。男性儿童缺锌402例，占男性调查儿童的78．88％；女性儿童缺锌362例，占75．57％；总缺乏力764例，占77．33％；男女儿童锌含量性别间有显著意义。     

全寄宿学校学生微量元素营养状况分析

测定了两所全寄宿学校一、二年级学生头发微量元素锌、铜、锰、铅和宏量元素钙的含量，并研究了上述元素与学生身高、体重及学习成绩的相关关系。结果表明：招生条件相似的两所寄宿学校的锌水平存在着显著性差异，两所学校一年级学生平均发锌含量分别为（115．3±27．3）×10-6和（83.5±31.9）×10-6，二年级学生平均发锌含量分别为（12．1±25．3）×10-6和（97．6±31．8）×10-6，锌水平较高的学校学生的身高、体重亦显著高于低锌学校学生，由此可见全寄宿学校膳食结构的不同对学生身体微量元素水平及身体的发育有着极大影响。     

微量元素锌与反复呼吸道感染的相关性

对28例反复呼吸道感染患儿(下称复感儿)及26例健康儿进行微量元素发锌测定。发现前者发锌平均值为(92.3±14.7)×10~(-6),后者为(132.5±21.5)×10~(-6),P<0.01,差异非常显著。对复感儿进行口服锌治疗,观察其疗效及治疗前后发锌变化。治疗前发锌平均值为(92.3±14.7)×10~(-6),治疗后为(137.5±20.2)×10~(-6),P<0.01差异非常显著。有效率达85.7％。故缺锌可能是复感儿患病的影响因素之一,锌治疗小儿反复呼吸道感染是十分必要的。     

微量元素影响幼儿智力发育多因素分析

研究了3609名1～岁儿童头发中微量元素与儿童智力发育不全的关系.结果表明,智力发育不全(IQ值55～69)儿童的发Zn为(68.24±16.56)×10-6、Pb为(14.73±8.68)×10-6;高智商(IQ值109～131)儿童的发Zn为(98.62±20.47)×10-6、Pb为(7.92±6.31)×10-6.正常儿童头发中Zn含量[(83.16±19.35)×10-6]显著高于智力发育不全儿童[(80.08±18.47×10)-6,P＜0.05].而正常儿童头发中Pb含量[(12.67±7.48)×10-6则明显低于智力发育不全儿童[(13.25±7.57)×10-6,P＜0.05].正常女童发Zn明显高于智力发育不全儿童的发Zn(P＜0.05).正常女童发Mn、Pb明显低于智力发育不全儿童的发Mn(P＜0.05)、Pb(P＜0.05).正常男童的发Zn、Cu明显高于智力发育不全儿童的发Zn(P＜0.05)、Cu(P＜0.05).正常男童的发Pb明显低于智力发育不全儿童的发Pb(P＜0.05).低锌高铅可能是儿童智力发育不全的重要致病原因.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.