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81.
本研究观察大鼠内毒素血症时肺组织中及外周血多形核中性粒细胞(PMN)凋亡,坏死及功能改变的差异。采用Wistar大鼠20只。腹腔注射LPS(O55B5,5mg/kg)造成内毒素血症,给予LPS后2,4,8,12小时(每组5只动物)取血及支气管肺泡灌洗,密度梯度法分离PMN,用流式细胞仪测定凋亡和坏死比例以及呼吸爆发功能的改变,同时采用5只大鼠作为正常对照。结果显示,内毒素血症时外周血和支气管肺泡灌洗液中PMN凋亡细胞比例相似。但与对照相比,外周血PMN坏死比例明显增加,呼吸爆发能力明显受抑,而支气管肺泡灌洗液PMN坏死比例显减少,呼吸爆发能力显增强。结论:在内毒素血症时,扣押于肺组织中的PMN在凋亡和坏死上表现出与比例显减少,呼吸爆发能力显增强,结论:在内毒素血症时,扣押于肺组织中的PMN在凋亡和坏死上表现出与外周血PMN不同的改变,其结果是组织中PMN存活增加,并持续处于活化状态,这与PMN造成组织损伤有关。  相似文献   
82.
【目的】了解手术创伤对术后全身炎症反应综合征 (SIRS)的影响。【方法】搜集外科重症监护室 (SICU) 335例患者的术后资料 ,分析不同手术组SIRS发病率 ;手术时间、失血量与SIRS持续时间的关系 ;SIRS持续时间与术后并发症的关系。【结果】术后SIRS发病率为 75 8% ,大手术高达 92 4 % ;无并发症患者失血量与SIRS持续时间呈正相关 (r1=0 783,P<0 0 1) ,手术时间与SIRS持续时间呈正相关 (r2 =0 398,P <0 0 1) ;随着SIRS持续时间延长 ,并发症发病率显著增高 (P<0 0 5 )。【结论】术后SIRS发生、发展与手术创伤密切相关 ;监测SIRS进程有助于及早发现并发症  相似文献   
83.
多层螺旋CT胸部低剂量扫描对气道三维重建的应用研究   总被引:5,自引:1,他引:4  
目的:比较低剂量与常规剂量条件下中央气道三维重建图像的差别,探讨低剂量螺旋CT扫描进行中央气道三维重建的可行性。材料和方法:32例病例行低剂量(50mAs)平扫及常规剂量(195mAs)平扫(1例)及增强扫描(31例),将两组原始数据分别普通算法及高分辨算法重叠重建出4组横断面图像,并进行气道SSD及VR重建,由两名放射科医师分析4组图像的质量、支气管显示情况、支气管病变检出情况,将结果进行统计学分析。结果:①图像质量:两组剂量间SSD图像质量无明显差异,高分辨重建图像质量≥普通算法重建图像质量;VR图像质量两种剂量之间无明显差异,高分辨算法图像质量≥标准算法重建图像质量。②支气管显示:两名医生评价结果均表明对段以上支气管显示方面无论SSD图像还是VR图像,低剂量与常规剂量组以及两种算法图像之间均无明显差异。③病变检出:无论SSD还是VR图像4组图像对支气管病变的检出无差异。④剂量差别:低剂量扫描比常规剂量扫描辐射剂量大大降低(13.6~3.6mGy)。结论:与常规剂量扫描相比,低剂量薄层扫描气道三维重建图像质量、对中央气道显示及病变检出都无明显差异,而病人接受的辐射剂量却大大降低,因此低剂量薄层扫描气道三维重建可以代替常规剂量重建图像应用于临床气道病变显示。  相似文献   
84.
Serine hydroxymethyltransferase (SHMT) provides activated one-carbon units required for the biosynthesis of nucleotides, protein, and methyl group by converting serine and tetrahydrofolate to glycine and N(5),N(10)-methylenetetrahydrofolate. It is postulated that SHMT activity is associated with the development of methotrexate resistance and the in vivo activity of SHMT is regulated by the binding of N(5)-CHO-THF, the rescue agent in high-dose methotrexate chemotherapy. The aim of this study is to advance our understanding of the folate-mediated one-carbon metabolism in zebrafish by characterizing zebrafish mitochondrial SHMT. The cDNA encoding zebrafish mitochondrial SHMT was cloned, overexpressed in Escherichia coli, and purified with a three-step purification protocol. Similarities in structural, physical, and kinetic properties were revealed between the recombinant zebrafish mitochondrial SHMT and its mammalian orthologs. Surprisingly, leucovorin significantly inhibits the aldol cleavage of serine catalyzed by zebrafish cytosolic SHMT but inhibits to a lesser extent the reaction catalyzed by the mitochondrial isozyme. This is, to our knowledge, the first report on zebrafish mitochondrial folate enzyme as well as the differential inhibition of leucovorin on these two SHMT isoforms. Western blot analysis revealed tissue-specific distribution with the highest enrichment present in liver for both cytosolic and mitochondrial SHMTs. Intracellular localization was confirmed by confocal microscopy for both mitochondrial and cytosolic SHMTs. Unexpectedly, the cytosolic isoform was observed in both nucleus and cytosol. Together with the previous report on zebrafish cytosolic SHMT, we suggest that zSHMTs can be used in in vitro assays for folate-related investigation and antifolate drug discovery.  相似文献   
85.
86.
复杂主动脉病变的腔内血管外科治疗   总被引:3,自引:1,他引:2  
目的 探讨复杂主动脉病变的腔内血管外科治疗方法。方法 对21例合并有内脏动脉缺血等复杂的主动脉病变,双球管定位下经锁骨上动脉到股动脉交换导丝以确保真腔内植入带膜支架,对真腔完全被假腔压闭的患者采取真腔内加压推进以通过导丝,用超长带膜支架来封堵大破口治疗夹层合并巨大假性动脉瘤形成,对夹层合并腹主动脉瘤患者采取血管腔内技术联合开腹手术等方法。结果 术后内漏3例,其中2例7 d后停止,1例漏血持续存在。3例主动脉创伤术后完全康复,余18例复杂主动脉夹层术后即时造影示瘘口已被完整覆盖,假腔无血漏入,内脏动脉等恢复真腔供血。18例中6例合并肠管缺血,3例合并肾动脉缺血,3例肠管缺血、肾动脉缺血,2例腹主动脉真腔完全被假腔压迫,以及2例合并下肢缺血术后均逐渐恢复,无脏器及肢体缺血坏死发生。2例合并腹主动脉瘤夹层行支架型人工血管封闭夹层破口后行开腹手术切除腹主动脉瘤、人工血管置换。16例随访5~36个月,平均22.3月,1例内漏持续存在,但假腔未继续加大,其余患者存活良好。结论 对复杂的主动脉病变的治疗,通过对腔内血管外科技术进行改进,并适当结合传统手术方法,使某些过去被认为不能够治疗的复杂主动脉病变可得以成功治疗。  相似文献   
87.
The influence of age on the regional arterial and venous effects of serotonin (5-HT) was investigated in 13 young (aged 22-31 years) and seven older (aged 50-69 years) healthy volunteers. Single-dose infusions of 5-HT (1, 10, and 80 ng/kg/min) and of the 5-HT2 receptor antagonist ritanserin (50, 150, and 500 ng/kg/min) were administered into the brachial artery. Subsequently, the relative arterial and venous effects of the highest dose of 5-HT were investigated. Forearm blood flow (FBF) and maximum venous outflow (MVO) were measured by venous occlusion plethysmography. Heart rate (HR) and intraarterial (i.a.) blood pressure were recorded semicontinuously. In both age groups, 5-HT induced an initial transient arterial dilation, followed by a persistent increase in FBF for the doses of 1 and 10 ng/kg/min and a relative small decrease in FBF for the highest dose. In both age groups, the highest dose of 5-HT induced a similar large reduction in MVO (p less than 0.05 for both). The reduction in MVO was attenuated by ritanserin (500 ng/kg/min, p less than 0.05 for both groups). In the younger subjects, this dose of ritanserin also unmasked an arterial dilator effect of the highest dose of 5-HT (p less than 0.05). The single infusions of ritanserin did not influence FBF significantly in either study group. No significant differences were observed between the age groups. These results show that in the forearm of healthy subjects arterial and venous vascular responses to 5-HT were not age-related. In the arterial vascular bed, 5-HT acted predominantly as a vasodilator; at high doses, mainly venous vasoconstriction was observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
BACKGROUND AND PURPOSE: This study investigated the characteristics of intussusception in Taiwanese children of different age groups, including the incidence, length of hospitalization and hospital costs. METHODS: Children with a diagnosis of intussusception who were hospitalized from 1999 through 2001 were identified from a nationwide health insurance claims database. The incidence of intussusception was calculated by age, gender, and season. Length of hospitalization and hospital costs were also analyzed. RESULTS: A total of 6988 cases of intussusception were identified in Taiwan from 1999 to 2001. Among them, 4859 cases occurred in children below 15 years of age. The average incidence among children below age 15 years was 34.5 per 100,000, with a peak incidence of 118.8 per 100,000 observed among children younger than 24 months old. The highest incidence of intussusception in Taiwanese children occurred between 12 and 24 months of age. According to the data for patients below 15 years of age hospitalized for intussusception in year 2000, males were more likely to be affected than females (61.3% vs 38.7%). Intussusception-related hospitalizations were rare in infants in the first few months of life, increased in those 6 to 12 months old, and peaked among children 1 to 3 years old. Among the 952 patients with intussusception admitted to hospitals in 2000, 297 (31.2%) received surgery, incurring higher median medical costs (New Taiwan Dollars [NT dollars] 42,265 or US dollars 1234) and longer median hospital stay (6.2 days) than the 655 patients who did not require surgery (NT dollars 6290 or US dollars 185 for hospitalization of 2.4 days). CONCLUSIONS: The study found that the incidence of intussusception peaked in the second year of life in Taiwanese children. There was also a male predominance and lack of seasonal variation in incidence.  相似文献   
89.
Tumor metastasis to the pancreas is a rare but recognized cause of acute pancreatitis. Autopsy series have reported a 24-40% of pancreatic involvement in small cell lung cancer. However, only a very few cases of tumor-induced acute pancreatitis have been described. Budd-Chiari syndrome complicating lung cancer is a rarely reported condition. We report a 68-year-old woman with extensive small cell lung cancer with the unusual initial presentation of both acute pancreatitis and acute Budd-Chiari syndrome. This patient suffered from progressive epigastralgia for 3 weeks. Severe epigastralgia with radiation to back and progressive jaundice developed 2 days prior to admission. After admission, the liver enlarged rapidly and the ascites increased markedly. Chest roentgenogram showed a mass lesion over the left lower lung field. Poorly differentiated carcinoma cells were found in ascites and bone marrow. The patient died on the ninth day of hospitalization before chemotherapy was initiated. Prompt diagnosis of extensive-stage small cell lung cancer may allow early chemotherapy treatment which favorably influences recovery when the pancreatitis is mild. Although prolonged survival might have been expected had this patient recovered from pancreatitis and received chemotherapy, diagnosis was delayed due to difficulty in immunohistochemical diagnosis of the tumor and the unusual clinical presentation. The use of stains employing antibodies against neurofilament and neuron-specific enolase cell antigens is important for early diagnosis of poorly differentiated metastatic tumor cells.  相似文献   
90.
Following an encephalopathic illness, a 13-year-old Chinese boy had a partial form of Klüver-Bucy syndrome with emotional disturbance, recent memory loss, hypersexuality, and polyphagia. Other unusual features included narcolepsy, polydipsia, and polyuria. Virologic studies failed to incriminate the etiologic agent, including herpes simplex virus. Brain biopsy of the frontal lobe demonstrated Alzheimer type II astrocytosis.  相似文献   
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