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51.
标准位X线片上胸腰椎椎弓根轴线的放射学研究   总被引:4,自引:0,他引:4  
目的:研究标准正位X线片上T9~L5椎弓根轴线的放射学表现。方法:10具T9~L5脊柱标本,解剖成单个椎体。直视下沿椎弓根轴线置入导针。测量分析下列数据:标准侧位X线片显示导针达到椎体后壁及椎弓根中段时,标准正位X线片导针在椎弓根投影内的距离与椎弓根投影最大横径的百分比。另选4具T9~L5脊柱标本,根据上述数据,X线分步监测椎弓根螺钉植入。结果:标准正位X线片导针位于椎弓根中段时的百分比为(49.16±1.84)%~(51.83±2.53)%,各节段及左右侧椎弓根差异无统计学意义(P>0.05);导针位于椎体后壁时的百分比为(61.13±6.09)%~(74.68±6.13)%,左右椎弓根之间、T10 ̄T12之间、T9与L1 ̄L5之间差异分别无统计学意义(P>0.05),T10 ̄12与T9、L1 ̄5差异有统计学意义(P<0.001)。植入72枚螺钉,68枚位于椎弓根中心,4枚穿破椎弓根,穿破率5.56%。结论:标准正位X线片导针在椎弓根投影内的比值能间接表达椎弓根轴线,可为经椎弓根手术确定正确的进针轨道提供一种参考。  相似文献   
52.
Complicated parapneumonic effusion and empyema in children.   总被引:2,自引:0,他引:2  
BACKGROUND AND PURPOSE: Parapneumonic effusion and empyema are recognized complications of bacterial pneumonia. Optimal management in children, especially the duration of parenteral antibiotics and the role of surgery, is controversial. This study analyzed the clinical characteristics, management, outcome, and bacterial etiology of 59 patients with complicated parapneumonic effusion and empyema treated at a single medical center in Kaohsiung from January 1995 to March 2004. METHODS: The diagnosis of complicated parapneumonic effusion was based on the specific characteristics of pleural fluid, computed tomography or ultrasound findings, or direct visualization of loculations during the surgical procedure. RESULTS: Causative agents were culture-confirmed in 42% of the cases. Streptococcus pneumoniae was the leading pathogen in this series (20% of cases). None of the S. pneumoniae isolates were susceptible to penicillin. Mycoplasma pneumoniae accounted for 19% of cases based on immunoglobulin M assay. CONCLUSIONS: An initial combination therapy regimen consisting of cefotaxime or ceftriaxone plus macrolide provided reasonable activity against 80% of the pathogens isolated in this series. This study also revealed that prolonged parenteral antibiotic treatment resulted in longer length of hospital stay.  相似文献   
53.
目的 :研究急性肾衰时肾微血管的损伤及樟柳碱、东莨菪碱、山菪莨碱对这些损伤的影响。方法 :采用左肾动脉注射油酸的方法建立大鼠急性肾衰模型 ,采用电镜、光镜及TTC显色观察大鼠急性肾衰不同时期肾微血管超微结构、肾组织结构及TTC显色的改变。结果 :左肾动脉注射油酸后 1 0min ,肾小球毛细血管内皮细胞坏死 ;肾小球毛细血管不同程度充血肿胀 ,在皮质与髓质交界区 ,可见小血管内充满大量红细胞 ;TTC显色呈鲜红色。注射油酸后 6h和 2 4h上述损伤加重 ,TTC显然出现典型的不显色苍白区。三种莨菪药物不同程度减轻了急性肾衰时肾微血管损伤 ,改善了肾组织缺血 ,减少了肾小管上皮细胞坏死数。结论 :急性肾衰时很早即出现肾微血管的损伤 ,三种莨菪药对急性肾衰时肾微血管和组织结构的损伤均有保护作用。  相似文献   
54.
An increasing demand for polycistronic vectors that express multiple genes simultaneously has arisen in recent years to obtain an efficient gene therapy. Armed with the knowledge that the expression of transgene in mammalian cells often requires tight control, we constructed in this study a tetracycline-regulated double-gene adeno-associated virus (AAV) vector carrying green and red fluorescent protein genes and expressed it in PC12 cells. When detected by fluorescence microscope and fluorescence-activated cell sorting, gene expression was induced by 44-66-fold and could be reversibly controlled by doxycycline. This double-gene AAV vector may be useful for regulated expression of two genes or a marker to monitor transgene expression.  相似文献   
55.
BACKGROUND: Schneider's first-rank symptoms involve an alienated feature of the sense of one's own mental or physical activity. To clarify the brain morphological basis for the production of these symptoms, volumes of the frontal and medial temporal regions and their clinical correlates were examined in patients with schizophrenia. METHOD: Twenty-two patients with schizophrenia and 44 age- and gender-matched healthy control subjects were included. All patients were in their psychotic episodes with definite Schneiderian symptoms, rated by using the Scale for Assessment of Positive Symptoms. Volumetric measurements of high-resolution magnetic resonance imaging were performed in the prefrontal area, cingulate gyrus, and precentral gyrus, and the medial temporal structures such as the amygdala, hippocampus, and parahippocampal gyrus. RESULTS: Patients had significantly decreased volumes in the cingulate gray matter and the amygdala compared to controls. In the patient group, Schneiderian symptom severity showed significant inverse correlations with volumes of the right posterior cingulate gray matter and of the left anterior parahippocampal gyrus. CONCLUSIONS: Schneiderian symptoms may be associated with morphological abnormalities in the limbic-paralimbic regions such as the cingulate gyrus and parahippocampal gyrus, which possibly serve the self-monitoring function and the coherent storage and reactivation of information.  相似文献   
56.
Anthropogenic environmental change will heavily impact cities, yet associated health risks will depend significantly on decisions made by urban leaders across a wide range of non-health sectors, including transport, energy, housing, basic urban services, and others. A subset of planetary health researchers focus on understanding the urban health impacts of global environmental change, and how these vary globally and within cities. Such researchers increasingly adopt collaborative transdisciplinary approaches to engage policy-makers, private citizens, and other actors in identifying and evaluating potential policy solutions that will reduce environmental impacts in ways that simultaneously promote health, equity, and/or local economies—in other words, maximising ‘co-benefits’. This report presents observations from a participatory workshop focused on challenges and opportunities for urban planetary health research. The workshop, held at the 16th International Conference on Urban Health (ICUH) in Xiamen, China, in November 2019, brought together 49 participants and covered topics related to collaboration, data, and research impact. It featured research projects funded by the Wellcome Trust’s Our Planet Our Health (OPOH) programme. This report aims to concisely summarise and disseminate participants’ collective contributions to current methodological practice in urban planetary health research.  相似文献   
57.
目的 了解郑州市新型冠状病毒肺炎患者定点收治医院护理人员的心理状况,从而为应对突发公共卫生事件医务人员的心理卫生、心理干预咨询提供参考的理论依据及指导.方法 选择本市新型冠状病毒肺炎疑似及确诊患者定点救治医院护理人员,共收集到462名护理人员信息,采用填写网络问卷SCL-90量表的方法进行调查,并与常模数据做对比,用SPSS19.0统计软件进行统计分析.结果 最终完成436名护理人员调查统计与分析,SCL-90量表总得分为(144.51±36.20),高于1986年全国常模(129.96±38.26)分以及2006年全国常模(130.021±33.626)分.其中,躯体化、强迫、抑郁、焦虑、恐怖因子分高于护士常模(P<0.05)及全国常模(P<0.05).结论 新型冠状病毒肺炎疫情期间,本市护理人员存在一定的心理压力.我们应注意到护理人员的心理压力以及引起压力的主要危险因素,并采取积极有效的方式应对,采取针对性措施进行疏导,减轻护理人员的心理压力,保证护理人员工作有效顺利进行.  相似文献   
58.
59.
目的:研究低功率氦氖激光对小鼠小脑信息传递物质的影响。方法:采用雄性BALB/C小鼠,随机分为对照组,辐射后即刻组、1h组、2h组,注入氮氖合酶(NOS)抑制剂的辐射后即刻组、副射后1h组,用波长632.8nm、功率密度5mW/cm^2连续氦氖激光每天局部辐射1次,每次1h,连续5d。对照辐射功率密度为0。结果:辐射组分别于辐射后即刻、1h小脑组织中一氧化氮(NO)代谢产物亚硝酸根(NO2^-)及环磷酸鸟苷(cGMP)含量均升高(P<0.01),辐射2h二者均降至正常,此增高效应可同时被NOS抑制剂阻断。结论:低功率氦氖激光可使小鼠小脑NO代谢产物NO2^-及cGMP含量短暂性升高,在氦氖激光辐射产生的生物学效应中涉及NO/cGMP信息传递机制。  相似文献   
60.
Acute leukemia is a clonal malignancy ofhematopoietic tissue characterized by proliferation ofabnormalblastcellsin the bone marrow and impairedproduction of normal blood cells.Magnetic resonanceimaging( MRI) isuseful in characterizing normal andabnormal bone marrow ( BM) because of its ability todistinguish fatfrom denser,more cellulartissuessuchas leukemia.MRIalso presentsa more global view ofthe BM than biopsy materials and,therefore,mayprovide a better understanding of diffuse hematopoi-…  相似文献   
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