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1.
本文报告了应用稳定性同位素~(58)Fe对三组缺铁性贫血儿童,分别摄取平衡膳、平衡膳加大豆蛋白膳和平衡膳加大豆蛋白加维生素C膳时,各组儿童膳食铁的吸收率。测定结果顺次分别为12.0±3.6%、10.7±4.7%和18.1±3.6%。后者高于前二者,差异显著。据此,作者同意国际营养性贫血咨询小组(INACG)以及大多数学者的主张,即大豆制品不利于或降低膳食铁的生物利用率(bioavailability)。本文并结合实验讨论了本法的原理、操作技术及误差控制等问题,评价了本法在类似工作中的重要意义。 相似文献
2.
目的 :在大肠杆菌内快速构建两种分别含有人肝细胞生长因子 (hepatic growth factor,HGF)和非分泌型人尿激酶型纤溶酶原激活剂 (urokinase- type plasm inogen activator,u PA) c DNA片段的重组复制缺陷型腺病毒。方法 :分别将人 HGF和 u PA c DNA片段与穿梭载体 p Track- CMV连接 ,线性化后与骨架载体 Ad Easy- 1在大肠杆菌 BJ5 183内同源重组获得腺病毒载体 p Ad HGF和 p Adu PA,经 2 93细胞包装后得到复制缺陷型重组腺病毒 Ad HGF和 Adu PA;将 Ad HGF和 Adu PA分别体外感染肝细胞株 L0 2 ,以 Northern印迹法和 Western印迹法检测两种病毒在肝细胞中的表达。 结果 :连接、重组后通过酶切和测序法筛选出病毒质粒 p Ad HGF和 p Adu PA;经 2 93细胞包装 ,3d后均观察到绿色荧光蛋白明显表达 ,Cs Cl梯度离心纯化最终分别获得 4× 10 1 0 efu/ m l滴度的重组病毒 Ad HGF和 6× 10 1 0 efu/ ml Adu PA;两种病毒体外感染肝细胞 3d后 ,HGF和u PA表达均明显增加。结论 :细菌内同源重组制备复制缺陷型腺病毒 ,纯化过程简单 ,重组腺病毒在肝细胞中均高效表达 ,为肝细胞移植基因治疗肝纤维化提供了新的手段 相似文献
3.
Shinichiro Iwata Yasunori Suda Takeo Nagura Hideo Matsumoto Toshiro Otani Yoshiaki Toyama 《Knee surgery, sports traumatology, arthroscopy》2007,15(4):343-349
The purpose of this study is to evaluate the relationship between the magnitude of knee laxity and posterior instability at
different knee flexion angles and clinical disability in isolated posterior cruciate ligament (PCL) deficient patients. Knee
laxity at 20° and 70° of knee flexion were evaluated using KT-2000 arthrometer, and the posterior instability at 20°, 45°
and 90° of flexion were evaluated using stress radiography. We assessed the differences in the knee laxity and the tibial
translation between isolated PCL deficient knees and normal knees, and between the patients with giving-way during activities
of daily living (ADL) and without giving-way. There were statistical differences in the knee laxity and the tibial translation
at all knee flexion angles between the PCL deficient knees and normal knees. The magnitude of the knee laxity at 20° of flexion
measured with KT-2000 arthrometer was significantly larger in the patients with giving-way than those in the patients without
giving-way although there was no significant difference in the tibial translation at 70° between the two groups. The tibial
translation in both medial and lateral compartments at 20° and 45° measured with stress radiography were significantly larger
in the patients with giving-way than those in the patients without giving-way although there was not significant difference
at 90° between the two groups. These results suggested that the magnitude of the knee laxity and the posterior tibial translation
at shallow knee flexion angles would be related to giving-way during ADL in isolated PCL deficient patients. 相似文献
4.
We report on an individual with trimethyl-aminuria, Prader-Willi syndrome, and del(15) (q11q13). To our knowledge, such an association has never been reported. Skin sores secondary to choline-rich foods and amenable to dietary control have not been described in trimethylaminuria, although they are seen in some patients with Prader-Willi syndrome. Pathogenesis, clinical diagnosis, and management of reported cases with trimethylaminuria are reviewed. Serious social and behavioral problems may result from strong body odor. Amelioration of the “fish odor” by dietary choline restriction makes trimethylaminuria detection important. Association of trimethylaminuria with Prader-Willi syndrome and del(15) (q11q13) in this patient is of particular interest. It may represent a contiguous gene syndrome, or deletion of the normal allele leading to expression of a single recessive trimethylaminuria gene, or an unrelated association, such as in Noonan syndrome. However, recent development of mapping of flavin-containing monooxygenase 2 (FMO2), the likely enzyme that is defective in fish odor syndrome, to chromosome 1q probably excludes pathogenetic association of fish odor syndrome with the Prader-Willi syndrome. © 1993 Wiley-Liss, Inc. 相似文献
5.
Aldo Scarpa Franco Bonetti Fabio Menestrina Marta Menegazzi Marco Chilosi Maurizio Lestani Chiara Bovolenta Giuseppe Zamboni L. Fiore-Donati 《Virchows Archiv : an international journal of pathology》1987,412(1):17-21
Summary The Southern blot hybridization technique has been applied to study the configuration of immunoglobulin and T-cell receptor genes in 6 cases of the so called mediastinal large cell lymphoma with sclerosis. This lymphoma has been recently recognized as a separate entity among non-Hodgkin lymphomas mainly affecting young adult patients. The B-cell origin of this neoplasm was suggested by means of immunohistochemical analysis. However, the immunophenotypical B-cell related markers used do not always exhibit lineage fidelity. The Southern blot analysis demonstrated the presence of unique heavy and k-light chain immunoglobulin gene rearrangements, establishing genotypically their B-cell origin.This work was supported by the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy, and Progetto finalizzato Oncologia (contratto no 86.00461.44), CNR, Rome, Italy. Aldo Scarpa and Maurizio Lestani are supported by a Scholarship from the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy 相似文献
6.
Adrian Bot Alpana Nangpal Luminita Pricop Bjarne Bogen Azad Kaushik Constantin A. Bona 《Molecular immunology》1996,33(17-18)
The contribution of the λ-light chain to the development of peripheral B cell repertoire and generation of specific antibodies to haptens and polysaccharide antigens was studied in genetically manipulated kappa-deficient and λ2-transgenic mice. The results clearly demonstrate a non-stoichiometric VH gene family expression in the absence of k-light chain and suggest a non-stochastic pairing between VH and Vλ genes, expressed in the peripheral B cell repertoire. A shift in VH gene utilization in the case of Vlλ+ antibodies was evident in response to β2–6 fructosan and TNP hapten. These observations demonstrate the availability of compensatory mechanisms in the absence of VK genes and are consistent with the hypothesis that VH gene family expression is controlled by genetic factors from inside the VH locus. Furthermore, genetic factors from outside the VH locus, namely restricted available light chain diversity, may lead to a shift in VH gene utilization in the peripheral B cell repertoire. 相似文献
7.
Objective: To investigate whether cockroach allergen extract can stimulate Protease-activated receptor 2 (PAR-2) expressed in mouse lung fibroblast.Materials: We established an immortalized lung fibroblast cell line, DM5, from PAR-2 deficient mice. By stable transfection with either an empty vector (DM5/EV) or an expression vector encoding mouse PAR-2 cDNA (DM5/Par2), a pair of lung fibroblast cell lines with or without functional PAR-2 expression were prepared.Treatment: The cells were exposed to cockroach allergen extract {up to 800 protein nitrogen unit (PNU)/ml}, trypsin (up to 100 nM), SLIGRL agonist peptide (up to 500 M), and trans-cinnamoyl-LIGRO agonist peptide (up to 400 M).Methods: The cells were loaded with Fluo-3 calcium indicator and mobilization of intracellular calcium with the stimuli was monitored by a fluorometric plate reader. Extracellular signal-regulated kinase (ERK) phosphorylation was examined by Western blot analysis using an anti-phospho ERK antibody.Results: The cockroach extract induced intracellular calcium transients in a concentration dependent manner in DM5/Par2 but not in DM5/EV. The activity was abolished when the cockroach extract was heat denatured or pre-incubated with PMSF (phenylmethanesulfonyl fluoride) prior to the assay. Concomitantly, ERK phosphorylation was seen in DM5/Par2 with the cockroach extract but not with a heat-denatured extract. The responses were sensitive to an inositol-1,4,5 triphosphate antagonist (2-APB) indicating that calcium was mobilized from intracellular store.Conclusions: Cockroach allergen extract can activate PAR-2 and thereby stimulate mouse lung fibroblasts likely through protease(s). The present study proposes a potential mechanism for cockroach antigens, similar to house dust mite antigens, in the etiology of respiratory diseases.Received 29 February 2004; returned for revision 12 April 2004; accepted by M. Katori 22 April 2004 相似文献
8.
目的 :探讨可溶性转铁蛋白受体 (sTfR)、血清中铁蛋白 (SF)在缺铁性贫血诊断中的意义。方法 :分别应用免疫比浊法和化学发光法测定缺铁性贫血、隐性缺铁患者和正常对照组的转铁蛋白受体和铁蛋白。结果 :缺铁性贫血组sTfR的值为 7.2 3± 4 .5 2mg/L ,明显高于隐性缺铁组 (2 4 3± 0 77mg/L ,P <0 0 1)和正常对照组 (1 34± 0 35mg/L ,P <0 0 1)。缺铁性贫血组和隐性缺铁组的SF分别为 :4 3± 1 8μg/L ,7 2± 3 7μg/L ,两组均明显低于对照组 (46 5± 18 2 μg/L)。结论 :sTfR是诊断缺铁性贫血的较敏感的指标 ,SF是诊断隐性缺铁可靠指标。联合检测sTfR和SF ,尤其是计算sTfR/SF对于早期诊断缺铁性贫血具有重要意义。 相似文献
9.
目的 阐明下丘脑室旁核催产素能神经元与免疫功能之间的联系 .方法 用免疫组织化学方法 ,对具有免疫功能缺陷的芳香烃受体 (Ah R)基因缺陷小鼠下丘脑室旁核催产素能神经元的形态特征进行观察 .结果 Ah R基因缺陷小鼠与野生型小鼠相比 ,催产素能神经元突起增多、增粗 ,许多粗大的纤维穿行至第三脑室室管膜下 .基因缺陷小鼠的下丘脑垂体束与野生型小鼠相比更加密集 ,纤维增粗 .结论 Ah R基因缺陷小鼠下丘脑催产素能神经元发生了塑性变化 ,提示催产素能神经元在神经免疫调节中可能具有重要作用 相似文献
10.