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131.
A survey of AFM1 residues in 58 commercial milk powder samples was carried out using an enzyme‐linked immunosorbent assay (ELISA) based on a monoclonal antibody against aflatoxin M1 (AFM1). The samples were collected from the USA (10), China (28), Italy (14), New Zealand (3) and Poland (3). The ELISA was performed without the need for clean‐up procedures. The data revealed that 4 (US), 21 (Chinese) and 1 (Polish) samples were positive for AFM1, with an average of 95.5, 102.8 and 85.0 pg g‐1 of the AFM1respectively.  相似文献   
132.
目的 评价3 2 磷简易敷贴药膜治疗小儿皮肤血管瘤的效果 .方法  2 4 5 0例不同年龄的血管瘤小儿接受3 2 磷简易敷贴药膜治疗 ,治疗次数为 1~ 9次 ,平均 3.5次 ;每次间隔 2个月 ,按不同年龄给不同的照射量 ,以治疗时间换算 ,每次治疗剂量为 0 .92 5MBq/cm2 × ( 12~ 4 2 )h .结果 血管瘤和血管痣治愈率 71.7% ,部分治愈 2 2 .5 % ,总有效率 94 .2 % ,无效者 5 .8% .其中血管瘤效果明显优于血管痣 (p<0 .0 1) ,并且年龄越小效果越明显 (p<0 .0 1) .结论 3 2 磷简易敷贴药膜治疗小儿皮肤血管瘤是一种治疗简便、疗效确切的方法 ,尽早治疗效果更明显  相似文献   
133.
王胜利  张仲才 《医学信息》2003,16(12):697-698
文章主要介绍了中小型图书馆在现有条件下,如何利用东方光驱魔术师软件科学管理光盘数据,节省经费,方便读者使用。  相似文献   
134.
观察自制冷冻干燥机冷冻干燥生物材料的效果。采用 R5 0 2压缩机和制冷剂制成 FD- 1冷冻干燥机。本实验冷冻干燥了胶原海绵、菌种及去纤酶。在冻干箱负载或空载情况下蒸发冷凝器温度均可达到 - 4 5℃ ,小冰箱可达到 - 30℃ ,冻干的胶原海绵具有许多孔洞的结构 ,冻干的菌种和去纤酶性能保持良好。 FD- 1冷冻干燥机适用于生物样品中小批量的冷冻干燥  相似文献   
135.
136.
To describe special facial features of children with Williams syndrome in China by using method of three‐dimensional craniofacial anthropometry. Using three‐dimensional stereo photogrammetric device, 14 craniofacial anthropometric measurements were performed and five indices were calculated in 52 children with Williams syndrome and 208 age and sex matched controls of Han Chinese ethnicity. Except intercanthal width, mouth breadth, morphological face height, nasal height‐breadth index, nasal breadth‐depth index, morphological ear index, the Williams syndrome group under 3 years old were smaller than the control group in the other 12 variables. Compared with the control group, the Williams syndrome group aged 3–5 years old had smaller biocular breadth, nasal length, nasorostral angle, bitragal breadth, ear width, morphological ear index and face depth. The Williams syndrome group aged above 6 years old had smaller biocular breadth, nasal breadth, bitragal breadth, ear width, ear length and face depth than the control group. The craniofacial variability index of the Williams syndrome group was greater than the control group. Greater variation was found among children with Williams syndrome than normal in China, specifically at eye, nose, ear and face shape, which demonstrate the usefulness of three‐dimensional stereo photogrammetric analysis in supporting accurate diagnose of the patient with Williams syndrome.  相似文献   
137.
EKLF/KLF1 was the first of the Krüppel-like factors (KLFs) to be identified in mammals and plays an important role in primitive and definitive erythropoiesis. Here, we identify and characterize EKLF in the chicken (cEKLF). The predicted amino acid sequence of the zinc finger region of cEKLF is at least 87.7% similar to mammalian EKLF proteins and is 98.8% and 95% similar to the EKLF orthologues in Xenopus and zebrafish, respectively. During early embryonic development, cEKLF expression is seen in the posterior primitive streak, which gives rise to hematopoietic cells, and then in the blood islands and in circulating blood cells. cEKLF mRNA is expressed in blood cells but not in brain later in chicken embryonic development. cEKLF mRNA is increased in definitive compared with primitive erythropoiesis. The conserved sequence and expression pattern of cEKLF suggests that its function is similar to its orthologues in mammals, Xenopus, and zebrafish.  相似文献   
138.
A dipstick dye immunoassay (DDIA) was developed to detect immunoglobulin G (IgG) or IgM antibodies of toxoplasmosis infection in humans. The assays employ a blue colloidal dye particles (D-1) conjugated to sheep anti-human IgG and rabbit anti-human IgM as the visualizing agents and a soluble antigen of tachyzoites of Toxoplasma gondii strain RH (TSA) as the detective antigen. The mixture of dye-labeled anti-human antibody-special human antibody was captured by TSA onto a nitrocellulose membrane dipstick by means of immunochromatography. The assays are rapid (the whole test can be completed within 15 min), simple, and cheap, and they don't require any equipment. They are sensitive and specific for the detection of anti-Toxoplasma IgG or IgM antibodies and generally agree closely with the results from the enzyme-linked immunosorbent assay. The assays are especially suitable for field applications.  相似文献   
139.
We assessed the functional determinants of the properties of L-type Ca(2+) currents in hair cells by co-expressing the pore-forming Ca(V)1.3alpha(1) subunit with the auxiliary subunits beta(1A) and/or alpha(2delta). Because Ca(2+) channels in hair cells are poised to interact with synaptic proteins, we also co-expressed the Ca(V)1.3alpha(1) subunit with syntaxin, vesicle-associated membrane protein (VAMP), and synaptosome associated protein of 25 kDa (SNAP25). Expression of the Ca(V)1.3alpha(1) subunit in human embryonic kidney cells (HEK 293) produced a dihydropyridine (DHP)-sensitive Ca(2+) current (peak current density -2.0 +/- 0.2 pA/pF; n = 11). Co-expression with beta(1A) and alpha(2delta) subunits enhanced the magnitude of the current (peak current density: Ca(V)1.3alpha(1) + beta(1A) = -4.3 +/- 0.8 pA/pF, n = 10; Ca(V)1.3alpha(1) + beta(1A) + alpha(2delta) = -4.1 +/- 0.6 pA/pF, n = 9) and produced a leftward shift of approximately 9 mV in the voltage-dependent activation of the currents. Furthermore, co-expression of Ca(V)1.3alpha(1) with syntaxin/VAMP/SNAP resulted in at least a twofold increase in the peak current density (-4.7 +/- 0.2 pA/pF; n = 11) and reduced the extent of inactivation of the Ca(2+) currents. Botulinum toxin, an inhibitor of syntaxin, accelerated the inactivation profile of Ca(2+) currents in hair cells. Immunocytochemical data also indicated that the Ca(2+) channels and syntaxin are co-localized in hair cells, suggesting there is functional interaction of the Ca(V)1.3alpha(1) with auxiliary subunits and synaptic proteins, that may contribute to the distinct properties of the DHP-sensitive channels in hair cells.  相似文献   
140.
淋巴细胞经TCR-CD3活化增殖作用的分析   总被引:1,自引:0,他引:1  
本文探讨了抗CD3单抗诱导的淋巴细胞活化增殖及有关影响因素。实验结果表明:①淋巴细胞内钙升高是淋巴细胞活化增殖的重要条件,CD3McAb引起的早期胞浆游离钙迅速升高主要由内质网释放钙离子所致,而淋巴细胞增殖不仅需要细胞内钙释放,还需要细胞外钙内流;②GTP结合蛋白是淋巴细胞激活过程的一重要环节,经G蛋白作用物霍乱毒素作用后,淋巴细胞DNA合成显著降低;③新霉素和PSS可抑制PLC和PkC的活性,对淋巴细胞NDA合成造成剂量依赖性抑制作用。此外,抗CD3McAb诱导的淋巴细胞DNA合成需要辅佐细胞的存在,高度纯化的T细胞对CD3McAb的刺激不发生增殖反应。  相似文献   
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