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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.
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 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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
Siqi Li  Xingpeng Chen  Jiaxi Xu 《Tetrahedron》2018,74(14):1613-1620
Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular SN2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.  相似文献   

19.
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   

20.
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.  相似文献   

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