Diffusion-weighted magnetic resonance imaging for demonstration of cerebral infarcts

Summary Forty-one patients demonstrating clinical symptoms for cerebral infarction were investigated by magnetic resonance imaging with diffusion-weighted echo-planar imaging (DWI) and T2-weighted imaging (T2WI). In 8 patients only DWI showed the cerebral lesions clearly. One patient with positive DWI and T2WI suffered from HSV encephalitis. DWI is superior to T2WI in assessment of small cortical infarcts and cerebral infarction in patients with preexisting vascular lesions. DWI is not specific, so other causes like cerebral hematoma and encephalitis have to be considered.      

MRI of a family with focal abnormalities of gyration

Focal abnormalities of gyration (FAG) are developmental disorders that may occur in isolated patients or, as in the case being reported, as part of a familial disorder. Analysis of individuals in a family spanning three generations was carried out using MRI. Abnormalities, present in all members of generations II and III, included focal cortical dysplasia (three patients), focal cortical infolding (two patients) and schizencephaly (one patient); associated minor anomalies, such as white matter abnormalities, were seen in the remaining three members of generations II and III. MRI recognition of FAG in the family being reported proved useful in defining their phenotypical expression and providing proper counselling for individual family members. Received: 22 August 1996 Accepted: 7 October 1996     

泪腺肿瘤中P53蛋白表达的意义

目的了解P53基因在泪腺肿瘤的表达及其临床病理学意义。方法应用免疫组织化学ABC法检测57例泪腺上皮性肿瘤患者和10例正常人泪腺组织中P53蛋白的表达情况，并与病理分级、复发相联系。结果10例正常人泪腺组织中P53表达全部为阴性；恶性肿瘤患者的表达率为48．6％，良性肿瘤中P53达率为18％，二者相比有显著性差异（P＜0．025）；复发患者阳性率为76．9％，明显高于未复发患为31．8％（P＝0．015）。结论P53基因参与了泪腺肿瘤的发生发展并与肿瘤的分化和复发有关。     

氯沙坦对维持性血透患者心血管保护作用的临床观察

目的 :观察氯沙坦对行维持性血透治疗的慢性肾功能衰竭 (CRF)患者心血管保护作用。方法 :6 0例维持性血透患者 (血肌酐≥ 70 0 μmol·L- 1 ) ,治疗组 (给予氯沙坦 5 0～ 10 0mg·d- 1 )及对照组 (给予非血管紧张素受体拮抗剂和非ACEI类降压药 )各 30例 ,记录用药前后各组患者血压 ,运用多普勒组织成像 (DTI)技术观察用药前后两组患者二尖瓣环峰值收缩速度 (VS)、收缩时间速度积分 (TVIS)、舒张早期速度 (VE)、舒张晚期速度 (VA)、VE VA 比值。结果 :治疗组及对照组患者治疗后血压均明显下降 ,二尖瓣环VS、TVIS、VE、VE VA ,则均明显上升 ;治疗组与对照组血压分别在治疗前、后相比并无明显差异 ;治疗前两组间二尖瓣环VS、TVIS、VE、VE VA 并无显著性差异 ,但在治疗12个月后 ,治疗组二尖瓣环VS、TVIS、VE、VE VA 则明显高于对照组。结论 :氯沙坦对行持续性血透的CRF患者具有良好的心脏保护作用 ,可有效改善其心功能 ,且不依赖于其降压作用     

胃复春片对慢性胃病患者窦D细胞的影响

目的：探讨胃复春片治疗慢性胃病患者前后生长抑素内分泌细胞(D细胞)数量变化。方法：用免疫组化酶链亲合素过氧化酶复合技术(SABC)对患者治疗前后胃粘膜组织的D细胞染色，观察治疗前后D细胞的形态和数量变化。结果：经胃复春片治疗后，患者胃窦粘膜D细胞阳性数及强阳性率均明显下降，有显著意义。结论：胃复春片对慢性胃病患者生长抑素D细胞有调整作用。     

Chronic Administration of Glucocorticoids Directly Upregulates Prepro-Neuropeptide Y and Y1-Receptor mRNA Levels in the Arcuate Nucleus of the Rat

The complete sequence of the cDNA encoding the neuropeptide Y (NPY) Y₁-receptor has recently been deduced from a rat brain library, and the presence of messenger ribonucleic acid (mRNA) encoding Y₁-receptor protein has been demonstrated within the brain. Using quantitative in situ hybridization histochemistry, the content and distribution of Y₁receptor and preproNPY mRNAs have been investigated in the hypothalamic arcuate nucleus of adrenalectomized rats receiving glucocorticoid replacement therapy for 12 days by means of either high doses of dexamethasone in their drinking water or by subcutaneous corticosterone pellets. Basal metabolic parameters such as weight gain or loss, blood glucose and plasma insulin were monitored: Dexamethasone treatment induced weight loss and a state of hyperinsulinemia with normoglycemia, while corticosterone treated animals displayed metabolic parameters identical to sham ADX animals. Within the arcuate nucleus of glucocorticoid treated animals, levels of Y₁receptor and preproNPY mRNAs were increased. In contrast, adrenalectomy itself had no effect upon Y₁-receptor mRNA levels or preproNPY mRNA levels in the arcuate nucleus. These studies demonstrate that glucocorticoids exert a stimulatory action on levels of Y₁-receptor mRNA and preproNPY mRNA levels in the hypothalamic arcuate nucleus. This is the first evidence to suggest that the expression of a neuropeptide-receptor gene in the central nervous system may be directly sensitive to peripheral hormonal signals.     

胚鼠黑质细胞悬液移植于帕金森病模型鼠侧脑室的实验研究

将胚鼠中脑腹侧组织制成细胞悬液移植于帕金森病(PD)模型鼠侧脑室,动态观察受体鼠在移植前后的行为变化。移植后16周应用诱发荧光及免疫细胞化学等方法,对移植物在受体鼠脑内的存活及生长情况进行了研究。结果,受体鼠旋转行为明显改善,侧脑室内可见黄绿色荧光细胞及酪氨酸羟化酶(TH)免疫反应阳性细胞,有的发出突起伸向室管膜及迁于尾核区.提示:移植的胚鼠黑质细胞生长良好,似作为触液神经元发挥其作用。     

阿魏酸在血瘀证兔体内的药代动力学

为验证及研究症治药动学假说（ｓｙｎｄｒｏｍｅａｎｄＴｒｅａｔｍｅｎｔＰｈａｒｍａｃｏｋｉｎｅｔｉｃｓ，Ｓ＆ＴＰＫ）的客观性和基本规律，本文以ＲＰ－ＨＰＬＣ法同时测定了活血祛瘀药物阿魏酸在正常及高分子右旋糖酐所制血瘀症（微循环障碍）兔体内经时浓度，以ＭＣＰＫＰ药动学程序在ＣＯＭＰＡＱ８０３８６机上自动拟合了药动学参数。统计结果表明，与正常组相比，阿魏酸在血瘀症兔体内的分布容积（Ｖ＿１和Ｖ＿Ｂ）及消除速率（ＣＬＢ）显著减小（Ｐ＜０．０５），半衰期（ｔ＿（１／２β）及相同时间段曲线下面积（ＡＵＱ）非常显著增加（Ｐ＜０．０１）。结论：实验结果基本符合Ｓ＆ＴＰＫ的观点：即同一药物在不同证兔体内的药代动力学参数经统计学处理有显著差异。     

Marked improvement of delayed methotrexate-induced leukoencephalopathy treated with high-dose folinic acid

We report the case of a patient with delayed methotrexate (MTX)-induced leukoencephalopathy who showed a marked improvement both in clinical and neuroimaging findings after a high-dose of the active form of folinic acid (leucovorin) treatment. The patient developed progressive affective impairment accompanied by headache, nausea and vomiting after treatment with MTX during the chemotherapy for acute lymphoblastic leukemia, and diagnosed as delayed type MTX-induced leukoencephalopathy. After an intravenous injection of high-dose folinic acid (total 1920 mg), neurological deficits and white matter changes dramatically improved in a few weeks. Although delayed MTX-induced leukoencephalopathy may cause irreversible brain damage, an early treatment with high dose leucovorin may thus facilitate the marked improvement of clinical findings and white matter abnormalities.     

Characterization and prediction of gradient acoustic noise in MR imagers

Gradient acoustic noise has been measured and characterized for an epoxy-potted, shielded gradient assembly in a 1.5 T MRI system. Noise levels vary by 10 dB or more as a function of longitudinal position in the scanner and reflect the pattern of forces applied to the gradient assembly. The noise level increases slightly (1–3 dB) with a patient in the scanner. The spectrum of the noise is similar (but not identical) to the spectrum of the input signal. A gradient-pulse-to-acoustic-noise transfer function was obtained by using a white noise voltage input to the gradient system. The transfer function enabled us to accurately predict acoustic noise output for a pulse sequence consisting of a series of trapezoidal pulses on a single axis and for a clinical fast spin echo sequence with gradients present on all three axes.