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41.
Acute encephalopathy associated with influenza and other viral infections   总被引:7,自引:0,他引:7  
Acute encephalopathy is the most serious complication of pediatric viral infections, such as influenza and exanthem subitum. It occurs worldwide, but is most prevalent in East Asia, and every year several hundreds of Japanese children are affected by influenza-associated encephalopathy. Mortality has recently declined, but is still high. Many survivors are left with motor and intellectual disabilities, and some with epilepsy. This article reviews various syndromes of acute encephalopathy by classifying them into three major categories. The first group caused by metabolic derangement consists of various inherited metabolic disorders and the classical Reye syndrome. Salicylate is a risk factor of the latter condition. The second group, characterized by a systemic cytokine storm and vasogenic brain edema, includes Reye-like syndrome, hemorrhagic shock and encephalopathy syndrome, and acute necrotizing encephalopathy. Non-steroidal anti-inflammatory drugs, such as diclofenac sodium and mephenamic acid, may aggravate these syndromes. Severe cases are complicated by multiple organ failure and disseminated intravascular coagulation. Mortality is high, although methylprednisolone pulse therapy may be beneficial in some cases. The third group, characterized by localized edema of the cerebral cortex, has recently been termed acute encephalopathy with febrile convulsive status epilepticus, and includes hemiconvulsion-hemiplegia syndrome and acute infantile encephalopathy predominantly affecting the frontal lobes. Theophylline is a risk factor of these syndromes. The pathogenesis is yet to be clarified, but an increasing body of evidence points to excitotoxicity and delayed neuronal death.  相似文献   
42.
目的 研究败血性急性肺损伤的动物模型,并探讨其在急性肺损伤研究中的意义。方法 用盲肠结扎穿刺(CLP)法的豚鼠急性肺损伤模型,结合动脉血气分析、外周血白细胞计数、肺湿重/干重比值(W/D)及肺组织病理观察。结果 CLP模型中动物的症状和表现缓慢出现,逐渐恶化.最后导致败血性休克,于2d左右出现大量死亡。结论 用盲肠结扎穿刺的方法制作豚鼠急性肺损伤动物模型较大鼠内毒素性休克,表现更类似于人类的肠源性肺损伤,且症状缓慢发生,逐渐恶化,有利于观察和进行各种干预。  相似文献   
43.
甲醛对小鼠致突变作用的研究   总被引:4,自引:0,他引:4  
目的 研究甲醛对小鼠的致突变作用。方法 选择健康昆明种小鼠 5 0只 (雌雄各半 ) ,随机分为 3个剂量组 :甲醛高剂量组 (2 0 0 0mg/kg·bw)、中剂量组 (2 0 0mg/kg·bw)、低剂量组 (0 2 0mg/kg·bw) ,1个阴性对照组 (生理盐水 )和 1个阳性对照组 (环磷酰胺 5 0mg/kg) ,采用腹腔注射染毒 ,每天 1次 ,连续 5d。于第六天处死雌性小鼠进行骨髓细胞微核试验 ,于第三十五天处死雄性小鼠进行精子畸形试验 ,显微镜下观察并计数微核及畸形精子数。结果 甲醛中、高剂量组骨髓细胞微核数显著高于阴性对照组 (P <0 0 5 ;) ,同时低、中、高剂量组精子畸形率显著高于阴性对照组 (P <0 0 1)。结论 甲醛对小鼠具有致突变作用  相似文献   
44.
BACKGROUND: Graft-vs.-host disease (GVHD) is the major cause of morbidity and mortality in patients undergoing allogeneic Bone Marrow Transplantation (BMT). The aim of our study was to identify the most relevant histological features for diagnosis of chronic Graft-vs.-Host Disease (cGVHD) in oral mucosa and minor salivary glands of 25 patients, as well as to evaluate the immunophenotype of the inflammatory cells. METHODS: Sixteen patients that were submitted to allogeneic BMT but did not present cGVHD were selected as a control group. The sections were studied on H & E and CD68, CD45, CD4, CD8, CD20 staining. RESULTS: The most frequent histologic findings in oral mucosa at the day of diagnosis of cGVHD were: hydropic degeneration of the basal layer of the epithelium, apoptotic bodies, lymphocytic infiltration, and focal or total cleavage between the epithelial and connective tissue. In the labial salivary glands (LSG), lymphocytic infiltration, acinar loss and fibrosis were the main alterations. Cytotoxic CD8-T cells and macrophages were predominant both in the epithelium and connective tissue, as well as in minor salivary glands. CONCLUSIONS: Histological features were useful in the diagnosis of oral cGVHD. It is suggested that CD8-T cells and macrophages play important role in the pathogenesis of the disease.  相似文献   
45.
BACKGROUND: The hamster cheek-pouch carcinogenesis model is a well-known animal system that closely mimics the development of premalignant and malignant lesions in human oral cancer. Our aim was to numerically characterize the premalignant and malignant lesions and expressions of field cancerization in this model using ploidy as the end-point. METHODS: To study the DNA content and proliferation status of the cells in this model we assessed the Feulgen reaction and the immunohistochemical reaction for 5-bromo-2-deoxiuridine (BrdU) in different histological areas of serial tissue sections of the cheek pouches of animals injected with BrdU. RESULTS: Ploidy values were higher in cancerized epithelia with no unusual microscopic features (NUMF), in preneoplastic and tumor areas than in control epithelia. The aneuploidy index was higher in NUMF areas than in control and differed significantly from control in preneoplastic areas and carcinoma. CONCLUSIONS: The unexpected alteration in DNA content observed in NUMF epithelia is of great relevance as a biomarker of field cancerized areas.  相似文献   
46.
Oral health was examined in a random sample of 1377 people in three 70-year-old cohorts studied within 5-yr intervals. During the studied period 1971-1983 the prevalence of toothlessness decreased from 52 to 34%. Toothlessness in men was more common in smokers, 48%, and ex-smokers, 32%, than in non-smokers, 20%. Eichner's index was used as a measurement of dental invalidity. This index showed a worse dental state among smokers and ex-smokers compared to non-smokers. Multivariate analyses indicated that tobacco smoking was a major independent risk factor for tooth loss in elderly men.  相似文献   
47.
Stewart J. Tepper  MD 《Headache》2006,46(S2):S62-S69
Many women report an increased frequency of headaches around the time of menses. For some women, these headaches are more severe, of longer duration, and lead to greater disability than those occurring at other times in the menstrual cycle. A headache diary is critical to properly diagnose menstrual migraine (MM) by prospectively documenting headache days, severity of headache, and the headaches' relationship to menses. In women with diagnosed MM, acute treatment has been proven to be effective in randomized clinical trials. For those women who have predictable periods and may require preventive therapy, short-term prevention is a reasonable approach due to the predictability of MM. Although several agents (eg, naproxen sodium, magnesium, triptans) have been evaluated for prevention of MM, all but triptans have been assessed in small trials of between 20 and 35 women. Naratriptan, frovatriptan, and, most recently, zolmitriptan have been proven effective in preventing MM. Triptans are generally well tolerated, and the long-term safety of these agents is currently being evaluated. The flexibility of using acute and preventive therapy allows physicians to tailor treatment of MM and meet the needs of individual patients.  相似文献   
48.
目的:观察早期大剂量应用抗坏血酸(维生素C)对重症急性胰腺炎(SAP)大鼠的核因子-!B(NF-!B)的影响,研究其作用机制。方法:将72只SAP模型SD大鼠随机分成3组,每组各24只。A组:由大鼠股静脉滴注生理盐水5 ml/kg。B组:大鼠股静脉滴注Vit C 15 mg/kg加生理盐水至5 ml/kg。C组:由大鼠股静脉滴注Vit C 150 mg/kg加生理盐水至5 ml/kg。另取8只SD大鼠作为正常对照组。各组分别于8 h和24 h处死8只大鼠,采血测淀粉酶、脂肪酶、维生素C(PV-C)、超氧化物歧化酶(SOD)、TNF-αI、L-6。大鼠处死时分别取胰头组织3份,一份组织HE染色,行光镜检查,按Kusske的方法,对水肿、炎症、出血和坏死分别评分;一份制成超薄切片,行电镜检查;另一份SP法进行免疫组化染色,检测NF-!B的表达。每组另外8只大鼠观察3 d内存活情况,计算3 d成活率。结果:各组大鼠3 d内的生存率为正常对照组100%(8/8),A组0%(0/8),B组12.5%(1/8),C组50%(4/8),C组的3 d生存率显著高于其他两组(P<0.05)。各组的4项病理学评分均高于正常对照组(P<0.01),C组的4项病理学评分均低于A、B组(P<0.05)。透射电镜检查示C组中分泌颗粒较少,其包膜完整、内质网轻度肿胀、线粒体清晰,未见大片坏死。SAP大鼠体内淀粉酶、脂肪酶、细胞因子TNF-α和IL-6的水平明显增高,血清SOD和P-VC降低,胰腺组织中NF-!B活化阳性胰腺细胞数明显增多。C组的血清淀粉酶和脂肪酶低于A、B组(P<0.05),SOD和P-VC水平高于A、B组(P<0.05),血清TNF-αI、L-6水平低于A、B组(P<0.05),胰腺组织NF-!B活化水平低于A、B组(P<0.05)。结论:早期大剂量应用Vit C有助于及时提高SAP大鼠的P-VC、E-SOD水平,降低体内淀粉酶、脂肪酶、TNF-αI、L-6水平,其作用机制可能与大剂量Vit C抑制SAP大鼠体内NF-!B活化、在整体水平上抑制细胞因子基因表达、有助于机体免受自由基和过量细胞因子的损伤及减轻胰腺组织的病理性改变等因素有关。  相似文献   
49.
BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. Methods: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5.  相似文献   
50.
Abstract:   A 66-year-old man was referred to our hospital with chest discomfort and shortness of breath. Seven months previously he had undergone a laparoscopic left nephroureterectomy for a left renal pelvic tumor and was given two cycles of adjuvant chemotherapy (methotrexate, epirubicin and cisplatin). Echocardiogram showed an 8-mm sized mass extending from the right atrium into the right ventricle. On computed tomography, multiple lung tumors, as well as the right atrial and ventricular mass, were seen. The patient died of acute heart failure caused by right ventricular outflow obstruction. On autopsy, a right atrial and ventricular metastasis of the initial transitional cell carcinoma was found. The patient's cause of death was acute heart failure as a result of cardiac metastasis of his initial renal pelvic carcinoma.  相似文献   
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