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1.
儿童锌营养缺乏症的流行病学调查   总被引:2,自引:0,他引:2  
对390例有锌营养缺乏表现的0~6岁儿童.进行发锌检测及锌营养缺乏的相关因素分析。结果表明与无锌营养缺乏表现的儿童相比,缺锌率分别是90.6%及37%,发锌均值分别是78.8×10-6±17.82×10-6和116.4×10±26.42×10-6。体格发育正常的儿童发锌均值明显低于生长发育低下的儿童,分别是76.7×10-6±17.82×10-6和98.4×10-6±18.95×10-6。资料表明,年龄越小越易发生锌营养缺乏。  相似文献   

2.
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。  相似文献   

3.
广州地区妊娠妇女锌、钙代谢状况调查   总被引:3,自引:0,他引:3  
调查了31名早孕妇女的头发锌、钙含量,其中锌为(139.0±40.1)×10-6,钙为(1081±478)×10-6;中孕妇女37名,发锌为(142.4±25.2)×10-6,钙为(666.1±143.3)×10-6;而69名晚孕妇女头发锌含量为(140.9±25.0)×10-6,钙含量为(864.7±562.8)×10-6。对照组为非妊娠健康妇女,共41名,头发锌含量为(158.1±61.9)×10-6,钙含量为(1241±546)×10-6。结果显示,三期妊娠妇女的发锌、发钙含量均显著低于正常对照组。  相似文献   

4.
对82名苯作业工人和100名对照组工人的发铁、发锌和发铜含量水平进行了研究。结果揭示,油漆作业工人发铁含量为10.3×10-6±2.3×10-6,明显低于对照组(14.4×10-6±3.1×10-6).P<0.01,发铜含量为7.4×10-6±1.2×10-6,亦低于对照组(9.8×10-6±1.3×10-6).P<0.05;发锌含量为169.2×10-6±26×10-6,与对照组(172.5×10-6±28×10-6)基本相同,P>0.05.  相似文献   

5.
沙棘颗粒对发铅高儿童的干预治疗   总被引:3,自引:1,他引:3  
为探讨发铅值升高儿童的干预治疗方法,将45例发铅水平在10.14×10-6-17.38×10-6的儿童随机分为两组:治疗组口服沙棘颗粒冲剂;对照组口服“迪巧”。分别于干预2个月后复查了发铅水平。结果表明,治疗组(n=23)干预后的发铅水平由15.34×10-6±4.62×10-6下降到9.03×10-6±3.76×10-6,下降了41.1%;对照组(n=22)由14.82×10-6±4.37×10-6下降到10.54×10-6±3.62×10-6.下降了28.9%。干预前各组问发铅的水平没有差异(P>0.05),而干预后治疗组与对照组比较,对照组与治疗组之间有显著差异。提示沙棘冲剂有降低发铅水平的作用,效果较单用钙剂为好。  相似文献   

6.
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)。  相似文献   

7.
南城县学龄儿童发锌水平的研究   总被引:1,自引:1,他引:0  
采用原子吸收光谱法测定了南城县城关小学540名6-14岁学龄儿童头发中锌的水平。将所得数据在计算机上进行统计分析。结果表明,本资料属非正态性资料,样本中位数为108.3×10-6,其中男性为103.85×10-6,女性为111.5×10-6。男女间有显著差别。年龄与发锌值之间呈正相关。  相似文献   

8.
佝偻病患儿发中微量元素观察   总被引:1,自引:0,他引:1  
对48例佝偻病患儿发中锌、铅、铜3种元素用ICP-AES法测定,同时采患儿指端血用超微量分析仪测定血钙、磷、碱性磷酸酶(AKP),与正常组对比,以探讨佝偻病与微量元素的关系.结果表明:佝偻病患儿发锌、血钙、血磷低于对照组,发锌100.36×10-6±51.88×10-6,167.76×10-6±113.52×10-6,P<0.01;血钙4.77±0.86mg/dL,5.29±0.57mg/dL,P<0.05;血磷8.21±1.06mg/dL,9.45±1.44mg/dL,P<0.01,发铅、铜/锌比值及AKP高于对照组,分别为发铅46.7×10-6±26.7×10-6,26.79×10-6±11.6×10-6,P<0.01;铜/锌0.2589±0.187,0.1442±0.106,P<0.05;AKP36.43±24.65u,25.18±5.79u,P<0.05。提示婴幼儿体内锌含量不足及铅过高是引起佝偻病的原因之一。在防治佝偻病时,应补充微量元素锌.  相似文献   

9.
全寄宿学校学生微量元素营养状况分析   总被引:1,自引:1,他引:1  
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。  相似文献   

10.
714名0~6岁儿童头发中6种微量元素含量及水平分析   总被引:1,自引:0,他引:1  
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。  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.
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.  相似文献   

13.
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.  相似文献   

14.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
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.  相似文献   

15.
16.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

17.
Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.  相似文献   

18.
A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.  相似文献   

19.
A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).  相似文献   

20.
Both soluble guanylate cyclase (sGC) inhibitors ODQ 1 and NS2028 2 are synthesized via improved protocols. In the former case treating 3,4-dihydroquinoxalin-2(1H)-one oxime 8, which can be prepared in two steps from 1,2-benzenediamine, with 1,1′-carbonyldiimidazole (CDI) gives the dihydro-ODQ 10 that in the presence of KMnO4 oxidises to give ODQ 1 in an overall yield of 46% starting from 1,2-benzenediamine. In the latter case, the synthesis affords NS2028 2 from 2-amino-4-bromophenol 3 in three steps with an overall yield of 85% and avoids the need for chromatography. Furthermore, Suzuki-Miyaura reaction conditions are described that enable the preparation of 8-aryl and 8-heteroaryl derivatives of NS2028 directly from NS2028 2. Finally, demethylation of the 8-(methoxyphenyl) substituted analogues afforded the 8-(hydroxyphenyl) derivatives 40-42. All new products are fully characterised.  相似文献   

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