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排序方式: 共有605条查询结果,搜索用时 31 毫秒
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本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。  相似文献   
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The UTX gene escapes X inactivation in mice and humans   总被引:7,自引:3,他引:7  
We recently have identified a ubiquitously transcribed mouse Y chromosome gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A peptide derived from the UTY protein confers H-Y antigenicity on male cells. Here we report the characterization of a widely transcribed X-linked homologue of Uty , called Utx , which maps to the proximal region of the mouse X chromosome and which detects a human X-linked homologue at Xp11.2. Given that Uty is ubiquitously transcribed, we assayed for Utx expression from the inactive X chromosome (Xi) in mice and found that Utx escapes X chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the mouse X chromosome have been reported previously to escape inactivation. The human UTX gene was also found to be expressed from Xi. We discuss the significance of these data for our understanding of dosage compensation of X-Y homologous genes in humans and mice.   相似文献   
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L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
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Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
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Over a follow-up period of 6 years, 4 out of 31 live related renal allograft recipients (12.9%) developed azathioprine induced bone marrow suppression. Presentation in 3 patients was with fever and 2 patients also had associated graft dysfunction. All patients had leucopenia, 2 patients in addition had anaemia and one patient had pancytopenia. Bone marrow suppression developed 9.6 months (3.5-16.0 months) following transplantation and recovery followed over a period of 30 (18-49 days) days after withdrawal of the drug. One patient succumbed during the phase of bicytopenia.KEY WORDS: Azathioprine, Bone marrow suppression, Kidney transplantation  相似文献   
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Multiple carcinoid tumors of the small bowel with more than 3 lesions are very unusual. The authors report a case with 4 lesions, 2 of those localized in the jejunum with more advanced infiltration of the wall and extension to regional mesenteric lymph nodes, revealed by ultrasonography. The relative low incidence and particularly the vague, nonspecific clinical presentation, the unusual site in the jejunum, and failure of the radiological examine of one year before lead to not suspect this condition prior to US examination. However, the feature of asymmetric, concentric thickening of the bowel wall requiring a more accurate exam by CT with oral contrast was able to confirm the suspect of the intestinal tumor. The patient, 80 year old, underwent radical surgery with a wide lymph nodes dissection as well as double resection of the jejunum and distal ileum. The post-surgical outcome was uneventful. A 12-month follow-up is free of the disease.  相似文献   
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