Effect of temperature in focal ischemia of rat brain studied by 31P and 1H spectroscopic imaging

³¹P, ¹H and lactate spectroscopic imaging was used to evaluate the effects of hypothermia on focal cerebral ischemia produced by middle cerebral artery occlusion. The effects on high energy phosphate metabolism, pH, lactate and NAA were investigated in 24 spontaneously hypertensive rats subjected to either permanent or transient ischemia. Under either normothermic (37.5°C) or hypothermic (32°C) conditions, with permanent 6-h occlusion, there was little difference between groups in either the NMR measurements or the volume of infarction. In animals that underwent 3 h of ischemia followed by 12 h of reperfusion, the ischemic changes in lactate, pH, NAA, and high-energy phosphate returned toward control values, and there was a protective effect of hypothermia (infarct volume of 211 ± 26 and 40 ± 14 mm³ in normothermic and hypothermic groups, respectively). Thus, hypothermia did not ameliorate the changes in lactate, pH, NAA, or high energy phosphate levels occurring during ischemia, however, during reperfusion there was an improvement in both the recovery of these metabolites and pathological outcome in hypothermic compared with normothermic animals.     

Mycotic aneurysm of the aorta: MRI and MRA features

Mycotic aneurysms of the abdominal aorta are potentially fatal but uncommon. We report the MRI and MRA features of an abdominal aortic mycotic aneurysm in a patient who presented with nonspecific low back pain. By delineating the saccular nature of the aneurysm and identifying the coexistence of vertebral enhancement, MRI was crucial for the final diagnosis. A potential pitfall of contrast-enhanced MRA is also demonstrated.     

高海拔（2261m）急性习服期大鼠脑内β—EP含量的实验研究（之三）

选用标化成年雄性Wistar大鼠、以放射免疫测定法（RIA），研究了大鼠由平原引入高海拔环境后，在24小时急性司服期，垂体及各脑区内β－内啡肪样免疫活性物质（β－EPLI）的含量变化。结果表明，大鼠引入高海拔环境后脑内β－EP含量发生明显的动态变化。高海拔实验组与平原对照组相比，垂体内β－EP含量降低非常显著（P＜0．01）。纹状体、下丘脑、丘脑、桥延、海马、皮层内β－EP含量增加非常显著（P＜0．01）。中脑内β－EP含量虽然也增加，统计学处理无显著性意义（P＞0．05）。据此推测：大鼠急进高海拔低氧环境后垂体β－EP的分泌与释放受到影响。提示，脑内β－EP参与低氧的应激反应过程，可能作为神经递质和调质，通过神经──内分泌环路在应激反应中起介导作用，β－EP可能为中枢神经系统内调节应激反应的主要应激激素之一。     

Gadoteridol dose dependence in MR imaging of a liver abscess model

A necrotic liver abscess model was studied with magnetic resonance (MR) imaging at 1.5 T before and after intravenous administration of gadoteridol at doses of 0.1, 0.25, and 0.5 mmol/kg in 24 rabbits. Enhancement characteristics and lesion delineation were assessed with both breath-hold and non-breath-hold imaging techniques. Lesion delineation, as assessed both by signal intensity measurements and evaluations by two image readers blinded to imaging technique, was greatest on high-dose (0.5 mmol/kg) breath-hold images. Lesion rim enhancement was seen consistently only on postcontrast images obtained at a dose of 0.5 mmol/kg and progressed with time after injection of contrast material.     

Percutaneous transhepatic stenting by wallstents of portal vein and bile duct stenoses caused by immunoblastic sarcoma in a liver transplantation

Posttransplant lymphoproliferative disorders are infrequent tumors related to chronic immunosuppressive therapy. We present a liver transplant recipient who developed such a tumor in the porta hepatis that provoked obstruction of the entire portal triad. Treatment consisted of systemic chemotherapy, percutaneous dilatation, and placement of Wallstent endoprostheses across both biliary and portal vein stenoses. The patient died 3 weeks later of pneumonia and sepsis. At necropsy, the tumor was completely necrosed and the prostheses in both the common bile duct and the portal vein were patent.     

矽肺动物模型全肺灌洗治疗的病理观察

通过对动物模型实验治疗的病理观察，评价全肺大容量灌洗治疗矽肺的效果，并优选灌洗液。对４０只家兔和１０只幼猪经ＳｉＯ２染尘处理后，各随机分为药物组、盐水组和对照组。４～５周后施行全肺大容量灌洗。治疗后３～５个月处死各组动物，进行病理双盲检查。经统计学秩和检验，兔与猪各组肺矽结节纤维化级别分布的差异有非常显著意义（Ｐ＜０．００５）。经卡方检验，各灌洗组的纤维化程度与对照组相比，差异亦有非常显著意义（Ｐ＜０．０１）。灌洗液中药与盐水比，Ｐ＜０．０５；盐水与西药比，Ｐ＜０．０５。兔和猪矽肺各灌洗组的效果明显优于对照组。灌洗液中药优于盐水，盐水又优于西药     

模拟高原和返回平原后大鼠心肌血流量的变化

目的：观察缺氧及停止缺氧后对大鼠心肌血流量的影响。方法：３４只Ｗｉｓｔａｒ大鼠，随机分为４组：①平原对照组；②急性缺氧组；③慢性缺氧组；④返回平原组。以放射性生物微球法测定心肌血流量。结果：急性缺氧引起ＰａＯ２、心输出量及氧运送量降低，但左、右心室心肌血流量明显增加；慢性缺氧时右心室收缩压、血球压积、血液粘滞性及右心室生理指数明显增加，而心肌血流量接近正常。停止缺氧３０ｄ后，上述所有指标均与平原以     

自发性高血压大鼠内皮素A型受体基因的表达

应用反转录－聚合酶链式反应（ｒｅｖｅｒｓｅｔｒａｎｓｃｒｉｐｔｉｏｎ－ｐｏｌｙｍｅｒａｓｅｃｈａｉｎｒｅａｃｔｉｏｎ，ＲＴ－ＰＣＲ）方法，测定大鼠ＥＴ－Ａ型受体（ｅｎｄｏｔｈｅｌｉｎＡｒｅｃｅｐｔｏｒＥＴＡ－Ｒ）ｍＲＮＡ在体内的分布，证明ＥＴＡ－ＲｍＲＮＡ不仅存在于血管平滑肌细胞，亦存在于内皮细胞中；而且广泛分布于脑、心、肾、肺等组织内。首次发现，在ＳＨＲ大鼠的脑、心、肾组织中，ＥＴＡ－ＲｍＲＮＡ水平明显升高，提示ＥＴＡ－Ｒ基因表达增加，亦可能是高血压发病的一个重要因素。     

Embolization of dural arteriovenous fistulas draining into the transverse or sigmoid sinus

The results of embolisation of dural arteriovenous fistulas draining into the transverse or sigmoid sinus were evaluated in 20 patients. Tinnitus was the main symptom in all patients although one also suffered from vertigo and sudden deafness. Nine patients were treated with PVA (polyvinylalcohol) alone and 11 with combined PVA and bucrylate (isobutyl-2-cyanoacrylate) in 1–9 procedures. Recurrence of symptoms, requiring repeated procedures was common but at subsequent clinical follow up 10 patients had no tinnitus, 5 were improved and only 5 experienced no change. Complications occured in six patients: four had transient neurological symptoms and one of these also developed a necrotic wound which later healed. One patient suffered from a cranial nerve palsy and one had an intracranial haemorrhage after a transvenous embolisation. This last patient recovered completely. The best clinical results were achieved in small fistulas and fistulas treated with combined bucrylate and PVA.