第四脑室肿瘤的MRI诊断（附12例报告）

本文分析了１２例经手术证实的第四脑室肿瘤的ＭＲＩ表现，认为ＭＲＩ确定肿瘤的起源、大小及其与周围正常解剖结构的关系非常可靠，第四脑室扩大，肿瘤周围有脑脊液包绕以及四叠体向后上方移位是四脑室肿瘤的可靠征象。单凭ＭＲＩ信号诊断四脑室肿瘤是不全面的。     

颅内多发原发性肿瘤的CT与MRI诊断

目的：报道１５例颅内多发原发性肿瘤的ＣＴ和ＭＲＩ表现，并评价ＣＴ与ＭＲＩ的诊断价值。方法：１５例颅内多发原发性肿瘤均行ＣＴ检查，其中４例行ＭＲＩ检查，均经手术病理证实。结果：多发胶质瘤４例，其中恶性室宫膜瘤３例，表现为脑室内及额顶叶脑实质内实质性肿块或囊性病变，多发星形细胞瘤１例，病变分别位于额叶及小脑蚓部；双侧听神经瘤及多发脑膜瘤各３例、ＣＴ和ＭＲＩ表现均较典型；脑膜瘤合并胶质瘤３例、脑膜瘤合并听神经瘤１例和垂体瘤合并胶质瘤１例。结论：结合肿瘤的ＣＴ和ＭＲＩ表现特点，可对大多数颅内多发原发性肿瘤作出正确诊断，ＭＲＩ对脑膜瘤的诊断优于ＣＴ。     

胃瘘并发Wernicke脑病一例

患者男，２３岁。１９９４年５月２日入院。入院前３个月因腹部外伤引起胃瘘，瘘口一直未能愈合。入院第９天视物不清，表情淡漠，双侧外展神经麻痹，眼球震颤，步态不稳。血常规、脑脊液检查未见异常。给予抗生素、激素等治疗未见好转。入院后第１０天病人意识朦胧、嗜睡。ＣＴ未见异常。ＭＲＩ平扫于第３、４脑室旁及导水管周围、乳头体见长Ｔ１、长Ｔ２信号，脑室壁模糊；增强扫描示上述部位明显强化（图１～３）。ＭＲＩ诊断：Ｗｅｒｎｉｃｋｅ脑病。入院后第１２天病人图１～３　Ｗｅｒｎｉｃｋｅ脑病ＭＲＩ增强扫描，示第３、４脑室旁…     

斜坡肿瘤的MRI诊断

目的 探讨ＭＲＩ诊断斜坡肿瘤的价值。材料与方法 回顾性分析３５例经病理证实的斜坡肿瘤的ＭＲＩ表现,其中２０例作增强扫描,观察各种病变的信号强度、大小、侵犯范围,并与ＣＴ表现进行比较。结果 斜坡肿瘤在ＭＲＩ上表现为正常斜坡被肿瘤组织所替代。信号不均匀,呈不均一强化;原发性肿瘤呈膨胀性生长,继发肿瘤多呈浸润性改变。ＭＲＩ显示斜坡肿瘤明显优于ＣＴ扫描。结论 ＭＲＩ能很好地显示斜坡肿瘤的大小、形态及其侵犯     

四脑室区肿瘤的CT和MRI诊断

本文收集了１９８８～１９９３年间经华山医院手术和病理证实的四脑室区肿瘤共４９例。作者分析讨论了其ＣＴ和ＭＲＩ特征，以及与肿瘤来源和病人年龄的关系，结果表明，四脑室区肿瘤的诊断须结合ＣＴ和ＭＲＩ表现、肿瘤来源及病人年龄综合判断，其中肿瘤来源对诊断尤为重要。     

颅内黑色素瘤的影像诊断(附7例分析)

目的：探讨颅内黑色素瘤ＣＴ、ＭＲ影像特征及其诊断。材料和方法：７例颅内黑色素瘤患者中男４例,女３例,年龄１０～５９岁。５例皮肤有黑色素瘤,２例有颅内黑色素瘤切除史。２例行ＣＴ加ＭＲＩ,４例单行ＭＲ,１例仅行ＣＴ检查。结果：３例ＣＴ平扫均为高密度影,形态不规则。增强扫描肿瘤明显增强。６例ＭＲＩＴ１ＷＩ肿瘤均表现为高信号,其中５例Ｔ２ＷＩ低信号,１例低高信号。Ｔ１ＷＩ增强扫描６例不规则增强。结论：颅内黑色素性黑色素瘤ＭＲＩ具有特征性表现,而非黑色素性黑色素瘤不具特征性,ＭＲＩ显示黑色素瘤累及脑实质及浸润脑膜的范围和定性诊断优于ＣＴ。     

儿童后颅凹肿瘤的CT, MRI诊断

目的：分析儿童后颅凹常见肿瘤的ＣＴ和ＭＲＩ影像学表现,提高诊断该病的准确性。材料和方法：收集儿童后颅凹常见肿瘤４０例,其中髓母细胞瘤１８例,星形细胞瘤１３例,室管膜瘤９例。行ＣＴ和ＭＲＩ检查。ＣＴ平扫４０例,增强扫描３２例;ＭＲＩ平扫２８例,增强扫描１６例。将其结果与手术病理对照。结果：４０例儿童后颅凹常见肿瘤ＣＴ显示率为９７５％,ＭＲＩ显示率为１００％。术前ＣＴ定性误诊１１例,准确率为７２５％。术前ＭＲＩ定性误诊４例,准确率为８５７％。ＣＴ和ＭＲＩ联合检查,能对后颅凹多数常见肿瘤作出定位及定性诊断。ＭＲＩ能多方位成像,去除后颅凹颅骨伪影的干扰,对该病的定位定性诊断明显优于ＣＴ。结论：ＣＴ和ＭＲＩ检查相结合,能提高诊断儿童后颅凹常见肿瘤的准确率,为临床提供更准确的诊疗信息。     

第三脑室肿瘤的CT和MRI诊断

本文回顾了１５例病理证实的第三脑室肿瘤的ＣＴ和ＭＲＩ表现，包括６例星形胶质细胞瘤，３例胶样囊肿，２例颅咽管瘤，２例畸胎瘤，１例室管膜瘤，１例神经母细胞瘤，讨论了它们的影像学特征及其鉴别诊断。ＣＴ显示钙化敏感，对肿瘤诊断帮助很大，ＭＲＩ具有多维成像能力，可准确确定肿瘤的位置及范围。     

鳞状乳头型颅咽管瘤的临床、病理及MRI对比分析

目的 研究鳞状乳头型颅咽管瘤的临床、病理及ＭＲＩ表现,并进行对比分析及鉴别诊断。方法 选取经临床及病理证实的鳞状乳头型颅咽管瘤３５例,均行ＭＲＩ扫描,男２２例,女１３例,采用美国ＧＥＳｉｇｎａ１．５Ｔ或０．５Ｔ超人振扫描仪,结果 鳞状乳头型颅咽管瘤在３５￣４５岁发病率最高,２４例有视野改变;２７例位于鞍上,１４例长入第３脑室,肿瘤直径在１２￣５６ｍｍ之间。肿瘤呈呈类圆莆１０例,边缘不规则型或分叶型     

眼色素膜黑色素瘤的CT与MRI研究

目的研究色素膜黑色素瘤的ＣＴ和ＭＲＩ表现，探讨最佳ＭＲＩ的扫描序列。材料与方法１５例患者用各种ＭＲＩ序列进行扫描，其中１１例行ＣＴ扫描，并与手术病理进行对照。结果ＣＴ示９例表现为与眼外肌等密度的肿块，２例肿瘤太小未能显示。ＭＲＩ示１４例具有典型的短Ｔ１、短Ｔ２信号，１例３ｍｍ高度的虹膜黑色素瘤在Ｔ１ＷＩ上未能显示；１１例伴有视网膜脱离，呈短Ｔ１及长Ｔ２信号，与肿瘤在Ｔ１ＷＩ上很难区分。使用脂肪抑制和增强扫描的Ｔ１ＷＩ能较好地显示较小肿瘤（高度＜５ｍｍ）能区分肿瘤及其伴发的视网膜脱离。结论ＭＲＩ显示黑色素瘤的准确率和特异性较ＣＴ和Ｂ超优越。     

Glutamine supplementation in vitro and in vivo,in exercise and in immunodepression

In situations of stress, such as clinical trauma, starvation or prolonged, strenuous exercise, the concentration of glutamine in the blood is decreased, often substantially. In endurance athletes this decrease occurs concomitantly with relatively transient immunodepression. Glutamine is used as a fuel by some cells of the immune system. Provision of glutamine or a glutamine precursor, such as branched chain amino acids, has been seen to have a beneficial effect on gut function, on morbidity and mortality, and on some aspects of immune cell function in clinical studies. It has also been seen to decrease the self-reported incidence of illness in endurance athletes. So far, there is no firm evidence as to precisely which aspect of the immune system is affected by glutamine feeding during the transient immunodepression that occurs after prolonged, strenuous exercise. However, there is increasing evidence that neutrophils may be implicated. Other aspects of glutamine and glutamine supplementation are also addressed.     

Temporal changes in the oxidation state in in vitro blood

The rates at which the paramagnetic compounds deoxyhemoglobin (Hb) and methemoglobin (MHb) form in vivo within an area of hemorrhage are unknown. The present experiment establishes the baseline concentrations and rates of change in paramagnetic hemoglobin concentrations, as well as the pH in normal heparinized and clotted human blood maintained in vitro at 37 degrees C under anaerobic conditions over 30 hours. There was a moderate increase in Hb concentration in normal heparinized blood (average increase was 15.5%, rate = 0.50%/hour) and a slight increase in MHb concentration in the heparinized blood and clots (average increase was 1.4%, rate = 0.044%/hour). A second experiment was done to verify the activity of the RBC systems responsible for maintaining the hemoglobin molecule in the reduced state. Conversion of MHb to Hb in these samples proceeded at a rate of 5.6%/hour. In a third experiment, blood from 11 normal subjects maintained at 4 degrees C 25 degrees C was analyzed for MHb concentration over the course of 28 days. The level of MHb formation remained in the range of normal for at least 11 days in all subjects. The authors conclude that at basal conditions created in vitro, the blood levels of both Hb and MHb remain at relatively low levels. Therefore, if the accumulation of Hb and/or MHb occurs in acute in vivo hematomas it must be driven by intrinsic tissue factors.     

Carcinoma in situ in cryptorchid testes in post-pubertal patients]

The pathohistologic analysis of testis sections of 37 postpuberty patients with different types of cryptorchism is performed. The tissue samples were taken during orchiopehy, fixed in Bouin's solution and treated by the standard histologic techniques. The morphologic criteria are presented for identification of the presence of the so called carcinoma in situ cells found in two cases. Besides, in 13 patients rare, mainly single, atypical germinative cells were found in a smaller number of the seminiferous tubules. It has been concluded that the presence of carcinoma in situ cells in undescended testes of some patients and considering the simple way of sampling, lack of complications and high reliability of the diagnostic procedure, it is absolutely justified to take routine biopsy of testes during orchiopexy in each postpuberty and perhaps prepuberty patient.     

我国医用辐射防护研究概况

医学放射学技术的迅速发展及介入放射学在临床广泛应用，使更多的人受到电离辐射的照射，同时也促进了医疗照射防护工作的发展。文中重点综述了我国医用辐射防护工作者近年来在Ｘ射线ＣＴ的医疗照射防护、对介入放射学工作者的剂量监测以及应用医疗照射防护体系，降低医疗照射剂量等方面所作出的成绩和研究进展     

Interventions in the chest in children

The scope for image-guided intervention in the chest is very wide and encompasses procedures in the heart, pulmonary and systemic vasculature, lungs and pleural cavities, airway, and esophagus. This review describes the most important procedures that are usually performed by radiologists. Percutaneous drainage is now the most common method of treating both empyemas and lung abscesses in children. Although most lung biopsies are carried out by other means, percutaneous biopsy and localization are important alternatives for the diagnosis of focal lung lesions. Esophageal strictures are common in children and are usually best treated by balloon dilatation. The use of retrievable or biodegradable stents has recently been introduced for refractory esophageal strictures. Similarly, balloon dilatation and stenting are now increasingly used in children with stenosis or extrinsic compression of the trachea or bronchi.     

Serum zinc in athletes in training

Serum zinc was determined using atomic absorption spectrophotometry in 160 training athletes (57 females) in the morning at rest. In 23.3% of the male and 43% of the female athletes, serum Zn was lower than the limit accepted for the normal range (75 microgram/dl or 11.5 mumol/l). The average serum Zn (96.7 +/- 12.6 microgram/dl) and the range of the values found in a control group of 15 young adult males did not differ from the accepted values in the literature. In 22 randomly selected male athletes, serum Zn fractions were determined using polyethylene glycol precipitation at pH 7.1; 22.2% of total Zn was bóund to alpha2-macroglobulin, the ratio being very close to 1 atom of metal per molecule of globulin. The possible reasons that may influence the serum Zn level in athletes are discussed with regard to the present knowledge in both exercise physiology and metabolism of zinc in man.