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71.
72.
应用电子自旋共振波谱仪(ESR)直接检测了缺血-再灌注兔心肌肌浆网自由基的变化,以探讨肌质网系统与氧自由基的关系。实验中将20只兔随机分为再灌注对照组、超氧化物歧化酶(SOD)组、ATP-氯化镁组和人参皂甙Re组。实验结果,g值2.0046处为半醌自由基波谱,其相对浓度各组依次为78.94±2.126,14.46±2.86,20.65±7.65,14.66±3.67(x±SD),对照组与用药组均有显著性差异(P<0.05),表明缺血-再灌注兔心肌肌浆网产生大量的自由基,用ESR可以直接检测到半醌自由基,外源性高能磷酸盐制剂ATP-氯化镁及人参皂甙Re与超氧化物歧化酶一样,发挥清除兔心肌肌浆网自由基的作用。  相似文献   
73.
JC virus (JCV) is a causative agent of progressive multifocal leukoencephalopathy and belongs to Polyomavirus. In this article we describe our recent research relating to this virus. First, JCV's major capsid protein VP1 possesses a nuclear localization signal (NLS) and has the ability to construct a virus-like particle (VLP). We have investigated the mechanism of nuclear entry of JCV using VLP, and clarified the role of NLS. In vitro transport assay revealed that wild type VLP (wtVLP), but not deltaNLSVLP, entered the nuclei of cells. The nuclear transport of wtVLP was dependent on the addition of importins alpha and beta and was prevented by antibodies to nuclear pore complex (NPC). These results suggested that JCV VLP binds to cellular importins via the NLS of VP1 and is transported into the nucleus through the NPC. Second, a yeast two-hybrid screen of a human brain cDNA library demonstrated that the fasciculation and elongation protein zeta 1 (FEZ1) and the heterochromatin protein lalpha (HPla) are proteins that interacted with JCV agnoprotein (Agno). In vitro binding assay showed that Agno interacts directly with FEZ1 and HPlalpha. We have also shown that Agno induces the dissociation of FEZ1 from microtubules and dissociates the interaction between HPlalpha and lamin B receptor. We have demonstrated that interaction between Agno and these host proteins inhibited nuclear egress of JCV. Third, in order to inhibit JCV infection in infected cells, we synthesized siRNA which is specific for JCV Agno. Immunoblotting and immunocytochemical analysis demonstrated that expression levels of agnoprotein and VP1 were significantly inhibited by specific siRNA. In addition, levels of viral mRNAs and viral production were decreased in the cells transfected with Agno siRNA. Furthermore, viral production of cell treated with Agno siRNA was significantly inhibited. These results indicate that post-infection treatment with siRNAs, that targets JCV Agno suppresses virus production in JCV infected cells. Thus, siRNA directed against JCV encoding genes may provide a useful tool for suppression of JCV infection.  相似文献   
74.
Dens invaginatus is a developmental variation resulting from an alteration in the normal growth pattern of the dental papilla. Synonyms of this disturbance include dens in dente, invaginated odontome, tooth inclusion, and dentoid in dente. Radiographically, it is observed as infolding of a radiopaque ribbon-like structure, with equal density as enamel, extending from the cingulum into the root canal and sometimes reaching the root apex, assigning the appearance of a small tooth within the coronal pulp cavity. This article presents 2 case reports. The first describes an 8-year-old girl with dens invaginatus in a mesiodens; the second report describes a 16-year-old boy presenting with 2 mesiodens, both associated with dens invaginatus.  相似文献   
75.
Silent cerebral lesions are increasingly found in mass screenings using MRI and magnetic resonance angiography (MRA). The purpose of this paper is to assess the usefulness of two non-invasive clinical tests-carotid ultrasound examination and brachial-ankle pulse wave velocity (baPWV) measurement-for predicting silent cerebral infarction (SCI) and silent intracranial arterial stenosis. Data were collected on 480 asymptomatic adult subjects who participated in a brain screening program at a single hospital between April 2003 and March 2006. All participants underwent baPWV measurement, B-mode ultrasonography of carotid arteries, MRI, and MRA. Data on 476 (99.1%) subjects were included in the analysis. Among these, 273 (57.4%) were male and the mean age was 51.5 years; 161 (33.8%) had carotid plaque; 33 (6.9%) had increased intima-media thickness (IMT); 99 (20.8%) had SCI; and 7 (1.5%) had intracranial arterial stenosis. The multivariate analysis showed that age (odds ratio [OR]: 1.12; 95% confidence interval [CI]: 1.08-1.17), carotid plaque (OR: 2.69; 1.59-4.56), increased IMT (OR: 2.40; 1.02-5.65), and a history of hypertension treatment (OR 2.22; 1.11-4.43) were significantly associated with SCI. Also, increased IMT (OR 9.70: 1.48-63.71) was related to intracranial arterial stenosis. Brachial-ankle PWV was related to SCI (p<0.01) and intracranial stenosis (p=0.01) in univariate analysis but not in multivariate analysis. The presence of carotid plaque and that of increased IMT on ultrasound examination are useful for assessing the risk of SIC. Increased IMT is also predictive of intracranial arterial stenosis.  相似文献   
76.
Hemosuccus pancreaticus (HP) is a rare cause of gastrointestinal bleeding, usually due to rupture of a visceral artery aneurysm in chronic pancreatitis. Other causes of HP are rare. We present a case of HP which occurred in a patient with chronic calcifying pancreatitis and a pancreatic pseudocyst documented by ultrasonography and computed tomography. With detectable fresh blood in the descending duodenum, an aneurysm in the pancreatic head was revealed by superior mesenteric angiography as the suspected origin of intermittent bleeding from the pancreatic duct. Because an artery feeding the pseudocyst could not be identified, angiographic embolization was not possible. Surgical resection or ligation was difficult by laparotomy; therefore, intraoperative packing of the pseudocyst with absorbable gelatin sponges was achieved via a cannula through a directly punctured site in the pseudocyst wall. The patient has been followed for 4.25 years with no further episodes of HP. It is possible that the packing of a pancreatic pseudocyst with gelatin sponges is a method that can be used in similar cases, where control of hemostasis is the primary concern. The packing of a pancreatic pseudocyst with gelatin sponges is a technique that can be performed not only via laparotomy but also via laparoscopy or concomitant angiography and ultrasonography.  相似文献   
77.
78.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
79.
We report a 59-year-old woman who underwent thoracoscopic extirpation of the intrapulmonary cystic lymphangioma which was located in the subpleural space of the left upper lobe. A chest X-ray showed a solitary round nodule in the left pulmonary hilum. A computed tomography scan revealed a mass shadow at the interlobar region surrounding the interlobar pulmonary artery. A round nodule was recognized as low signal intensity on T1-weighted images by magnetic resonance imaging. There was biphasic signal intensity on T2-weighted images as well. Radiologically, we diagnosed this lesion as a benign cystic tumor in the lung. Thoracoscopic observation revealed a cystic lesion just beneath the visceral pleura of the upper lobe adjacent to the interlobular pulmonary artery. As this suggested a benign bronchogenic cyst, we performed extirpation of the cyst under thoracoscopy. After this operation, the cyst was diagnosed as an intrapulmonary cystic lymphangioma pathologically.  相似文献   
80.
A patient with cerebral deep sinus thrombosis, which was not diagnosed on the first examination, is reported. A 46-year-old woman presented with headache and vomiting. Neurological examination and a brain computed tomography (CT) scan showed no obvious abnormal findings. The patient suffered disturbed consciousness on the day after the examination, and was admitted to our emergency centre. A CT scan and magnetic resonance imaging revealed an ischaemic lesion in the left basal ganglia, suggesting deep sinus occlusion. Anticoagulant therapy was administered. One day after admission, a CT scan showed a haematoma and severe brain swelling in the same region. Cerebral angiography demonstrated a straight sinus occlusion. Intracranial pressure was not controlled with hypothermia, and the patient died 25 days after admission. Review of the initial CT scan revealed subtle, early findings of deep venous thrombosis that were missed on first examination.  相似文献   
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