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1.
婴幼儿辅食的选择   总被引:1,自引:0,他引:1  
随着泌乳时间的延长,母乳中微量元素含量逐渐下降,加之婴儿期生长发育较快,应及时给婴儿补充一些富含微量元素的辅食,以补充母乳中微量元素的不足。从出生后三个月开始,母亲就应该开始补以一些富含铁的微量元素辅食。如何选择辅食却是很有学问的。我国婴儿生长发育到4~5个月后普遍不如发达国家那样好,因素很多,其中最重要的是辅助食品添加的数量和质量未达到婴儿生长发育的需要。  相似文献   

2.
卵巢癌患者血清中铜、锌含量及铜/锌比值分析   总被引:5,自引:0,他引:5  
为了解微量元素与卵巢癌的关系,对21例卵巢癌患者进行了血清Cu、Zn含量及Cu/Zn比值分析,并以30例健康女性为对照。结果表明,卵巢癌患者血清中Zn含量明显低于对照组(P<0.01),而Cu含量明显高于对照组(P<0.01),Cu/Zn比值也比对照组高。提示卵巢癌的发生与体内微量元素异常有关。  相似文献   

3.
中山市1387名青年学生头发微量元素检测与分析   总被引:1,自引:0,他引:1  
为了探讨中山市青年学生头发中的微量元素含量,测定了该市来自三个学校的1387名青年学生头发中的锌、铁、铜、钙、阵、锰、铅含量。结果表明,女生与男生的头发锌含量有显著差异(P<0.05),女生与男生的头发中钙含量有高度显著差异(P<0.001);城区与乡镇的青年学生头发中钙、铜含量有高度显著性差异(P<001);父母文化程度高与父母文化低的青年学生头发中钙含量有高度显著性差异(P<0.01);在青年学生的年龄、性别、家庭、居住地区等不同的比较中,以发钙值含量差异显著性最高。提示青年学生应注意饮食营养均衡,补充必需的微量元素,加强体育锻炼,对提高体系有一定的意义。  相似文献   

4.
反复呼吸道感染与微量元素的相关性研究   总被引:3,自引:0,他引:3  
为探讨反复呼吸道感染与微量元素锌、铜、铁、钙的关系,剪取枕后下头发0.5-1g,采用电感耦合高频等离子体发射光谱法检测了头发微量元素。结果表明:(1)反复呼吸道感染患儿发锌、铜、铁、钙含量明显低于正常健康儿童,差异有极显著性(P均<0.01)。(2)反复呼吸道感染患儿经过补充微量元素后,发锌、铜、锌、钙含量明显高于补充微量元素前,有显著性(P<0.01或<0.05)。(3)56例反复呼吸道感染患儿经过补充微量元素后,随访其后1年内呼吸道感染次数的变化,明显减少者占80.4%;基本没变者占19.6%。可见,微量元素缺乏是引起反复呼吸道感染的重要原因之一。补充微量元素可减少呼吸道感染的次数。  相似文献   

5.
为了解肝豆状核变性患者头发微量元素的含量,以及微量元素与肝豆状核变性病的关系,用火焰原子吸收分光光度计分别测定了患者和健康者头发的铜、锌、钙、铁的含量。结果表明,患病组头发与健康头发铜、锌、铁含量均在正常范围,无显著性差异(P〉0.05),而患者头发钙含量明显低于健康组头发含量,有显著性差异(P〈0.05)。可见患者发铜、锌、铁含量测定对肝豆状核变性病临床诊断没有意义,而发钙与肝豆状核变性病有密切关系,能反映患者体内钙代谢情况,提示患者排铜治疗的同时应及时补钙。  相似文献   

6.
为探讨 2~ 4个月婴儿头发微量元素的含量和相关性 ,用电感耦合高频等离子体发射光谱法测定了广州市 1 0 0 7例 2~ 4个月健康婴儿的头发中Zn、Fe、Cu、Ca、Mn、Pb 6种元素的含量 ,并用SPSS统计软件包进行了数据处理和相关性分析。结果表明 ,2~ 4个月男女婴儿微量元素以低Zn最为明显 ,分别是 3 3 8%和 3 5 4% ,无性别的差异 (P >0 0 5 ) ;其次是低Cu、Ca、Mn,存在性别的差异 (P <0 0 5 ) ;高Pb分别是 3 5 7%和 2 4 6% ,有性别的差异 ,男婴高Pb比女婴严重(P <0 0 5 )。Fe与Zn、Cu与Ca、Mn与Zn有正相关性 (P <0 0 5 ) ;Pb与其它微量元素含量不存在相关性 (P >0 0 5 )。提示 :广州市 2~ 4个月婴儿存在不同程度的微量元素缺乏 ,母婴均应注意均衡饮食 ,避免铅暴露  相似文献   

7.
对产后1-6个月的乳母及其婴儿分别进行了乳汗中钙、铁、锌含量测定和婴儿身高、体重测量。结果显示,母乳中钙、铁含量与国内资料接近, 而锌含量偏低;乳汁中的铁和锌含量随喂养时间延长而逐渐下降;钙含量在四个月半前无明显变化,五个月后呈下降趋势。相关统计结果表明,乳汁中的钙、铁与婴儿的身高、体重无显著相关(P>0.05),锌与婴儿身高、体重呈显著正相关(P<0.01)。  相似文献   

8.
为探讨儿童头发中微量元素是否有协同或拮抗作用,测定了646名1-3岁和3803名4-7岁儿童头发中的Zn,Fe,Cu,Ca,Mn和Pb含量,并研究了各元素间的相互关系,结果表明:1-3岁幼儿头发中Zn,Fe,Cu,Ca,Mn和Pb各元素间均呈正相关,4-7岁儿童的发锌含量与发铅含量呈非常显著负相关(P值均<0.001),其它各元素间均呈正相关。  相似文献   

9.
妊娠糖尿病与非妊娠糖尿病患者头发微量元素含量分析   总被引:2,自引:0,他引:2  
采用高频等离子体发射光谱法测定了妊娠糖尿病患者、非妊娠糖尿病患者以及相应对照组的头发微量元素锌、铁、铜、锰、锶、镁和常量元素钙的含量。56例健康妊娠妇女的发锌含量为(139.9±31.5)×10-6,而11例妊娠糖尿病妇女为(114.3±29.4)×10-6,两者比较差异有显著性,(P<0.05),其它元素铁、铜、锰、锶、镁和钙不存在显著性差异。而45例非妊娠糖尿病女性与33名健康非妊娠女性的头发微量元素含量比较表明:两者锌含量不存在显著性差异,但糖尿病组铜显著低于健康对照组(P<0.05),分别为(6.32±2.31)×10-6和(9.05±16.50)×10-6,糖尿病组铁含量(21.5±11.7)×10-6亦显著低于健康对照组(26.9±10.7)×10-6,其余元素无显著性差异。前后两组实验结果表明妊娠糖尿病患者与非妊娠糖尿病患者的微量元素代谢状况并不相同,妊娠糖尿病患者的锌缺乏状态值得引起注意。  相似文献   

10.
选取人类白细胞抗原(HLA-B27)呈阳性的强直性脊柱炎患者54例,采晨空腹血,用原子吸收光谱法测定了全血中锌,铜,铁,钙及锶五种必需元素的含量。与50名无关节炎者组成的正常对照组进行比较。结果表明,患者组全血锌,铁,钙含量显著低于对照组(P<0.01),锶低于对照组(P<0.05),铜无统计学意义。提示患者体内微量元素代谢失常,很可能与该病的发生与发展有一定的关系。  相似文献   

11.
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%.  相似文献   

12.
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.  相似文献   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

19.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

20.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

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