色素减少性蕈样肉芽肿的微小残留病变

作者报道1例I期色素减少性蕈样肉芽肿，患者为一13岁男孩，尽管临床上病情得到完全缓解，但T细胞受体γ多聚酶联反应发现仍有微小残留病变。通过对缓解后皮损的T细胞受体γ多聚酶联反应产物的进一步克隆和测序，发现原发性T细胞克隆仍存在，但数量有所下降。随访3年半，无任何新出皮损。蕈样肉芽肿残留的恶性T细胞克隆的临床意义还有待阐明。     

Increased basal and induced tyrosine phosphorylation of the insulin- like growth factor I receptor beta subunit in circulating mononuclear cells of patients with polycythemia vera

We have previously shown that circulating progenitor cells in patients with polycythemia vera (PV) are hypersensitive to insulin-like growth factor I (IGF-I) with respect to erythroid burst formation in serum- free medium, and that this effect occurs through the IGF-I receptor. To investigate the molecular basis of this IGF-I hypersensitivity phenomenon, we examined tyrosine phosphorylation of the IGF-I receptor beta subunit in peripheral blood mononuclear cells (PBMNC) from eight PV patients and six normals. Cells were exposed to IGF-I at concentrations of 10(-8) and 10(-10) mol/L for 0, 1, 3, and 10 minutes, and then lysed. The IGF-I receptor beta subunit was immunoprecipitated, and the protein was resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotted with antiphosphotyrosine antibody (4G10). We found that, in the absence of exogenous IGF-I, there was a basal level of tyrosine phosphorylation of the IGF-I receptor beta subunit, and it was substantially greater in PV than in normal. At 10(-10) mol/L IGF-I in normals, no evidence of increased tyrosine phosphorylation was detected; however in PV, a pronounced increase in tyrosine phosphorylation was observed at both 10(-10) and 10(-8) mol/L IGF-I, and it occurred earlier and attained a higher level than in normal. In contrast, in PBMNC from three patients with erythrocytosis, no significant increase above normal was seen in either basal or induced tyrosine phosphorylation of the IGF-I receptor beta subunit. Thus, our findings show two distinctive features of the PV phenotype in PBMNC: (1) an increased basal tyrosine phosphorylation of the IGF-I receptor beta subunit, and (2) a hypersensitive and hyperresponsive receptor with respect to tyrosine phosphorylation. These features may influence the ability of the receptor to transmit a proliferative signal; thus, they may play a role in the pathogenesis of PV.     

Intra-observer reproducibility in measuring new putative MR markers of demyelination and axonal loss in multiple sclerosis: a comparison with conventional T2-weighted images

New magnetic resonance (MR) measures considered to be putative markers of demyelination and axonal loss were found to be more closely related to clinical disability than T2-weighted MR imaging (MRI) findings in patients with multiple sclerosis (MS). In this study, we evaluated the reproducibility of such measurements in order to assess their reliability for longitudinal studies in MS. The intra-observer coefficients of variation for repeated measurements did not significantly differ among the MR techniques studied [2.6% for T2-weighted MRI, 4.38% for unenhanced T1-weighted MRI, 3.65% for magnetisation transfer imaging (MTI) and 2.28% for spinal cord cross-sectional area at C5]. Our findings suggest that non-conventional MR techniques may be reliable outcome measures for clinical trials in MS. Received: 16 July 1996 Received in revised form: 7 October 1996 Accepted: 16 December 1996     

拉氧头孢钠的极谱行为及其痕量测定方法

在HCI-KCI（ｐＨ1～2）介质中，用循环伏安和示差脉冲极谱（ＤＰＰ）等电化学方法研究了拉氧头孢钠（噻吗灵）的电极反应机理，并建立了用ＤＰＰ测定的新方法。其峰电位为-0.62V（ｖｓＡｇ/ＡｇＣｌ），峰电流与拉氧头孢钠浓度在1×10^-8～5×10^-6ｍｏｌ·Ｌ^-1（富集时间t_ac＝９０ｓ），5×10^-6～5×10^-5ｍｏｌ·Ｌ^-1（t_ac＝７０ｓ），5×10^-5～８×１０^-4ｍｏｌ·Ｌ^-1（t_ac＝30ｓ）范围内成线性关系。检测限为４×１０^-9ｍｏｌ·Ｌ^-1（t_ac＝９０ｓ）。本法可用于注射剂中该物质的测定，同时也探讨了直接测定尿中拉氧头孢钠的可能性。     

The impact of altitude on early outcome following the Fontan operation

Background  

The success of a Fontan circulation depends on several factors including low pulmonary vascular resistance. Pulmonary vascular resistance rises in response to hypoxia. Hypoxia is associated with altitude. Therefore, we wondered whether altitude is a risk factor for early failure after the Fontan operation. The aim was to test this hypothesis.