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排序方式: 共有187条查询结果,搜索用时 31 毫秒
1.
Thigh pain and multiple vertebral osteonecroses: value of magnetic resonance imaging. 总被引:1,自引:0,他引:1
We describe a 74-year-old woman who presented with referred thigh pain associated with multiple osteonecroses of the T12, L1 and L2 vertebrae. Magnetic resonance imaging was found to be a valuable diagnostic aid, revealing signs of spinal cord and nerve root compression related to the collapsed vertebrae. Biopsy of T12 confirmed the benign nature of the vertebral compression fracture. Our patient also showed histologically documented osteoporosis. 相似文献
2.
Strain-specific immune response to Haemophilus influenzae in chronic obstructive pulmonary disease 总被引:7,自引:0,他引:7
Sethi S Wrona C Grant BJ Murphy TF 《American journal of respiratory and critical care medicine》2004,169(4):448-453
Previous studies of immune response to Haemophilus influenzae after exacerbations of chronic obstructive pulmonary disease (COPD) have yielded contradictory results. Using homologous (infecting) strains and immunoassays to surface-exposed epitopes, we tested the hypothesis that adults with COPD make new antibodies to strain-specific, surface-exposed epitopes on H. influenzae after exacerbations. We collected clinical information, sputum, and serum monthly and during exacerbations from 81 patients with COPD over 56 months. Serum antibodies to H. influenzae after exacerbations associated with H. influenzae in sputum were detected with whole bacterial cell ELISA and bactericidal assays. An immune response to homologous H. influenzae occurred after 22 of 36 (61.1%) exacerbations with newly acquired strains compared with 7 of 33 (21.2%) exacerbations with preexisting strains (odds ratio [OR] = 4.4; 95%, 1.8 to 10.8; p = 0.001). An absence of an immune response was strongly associated with complement sensitivity (OR = 0.03; 95% confidence interval, 0.003 to 0.22; p = 0.001). New bactericidal antibodies developed after exacerbations were highly strain specific, showing bactericidal activity for only 11 of 90 (12.2%) heterologous strains. Development of an immune response to H. influenzae supports its role in causing exacerbations. The strain specificity of the immune response likely represents a mechanism of recurrent exacerbations. 相似文献
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4.
骨髓干细胞分化为肝细胞的多种移植途径 总被引:3,自引:0,他引:3
近年来许多研究证实,人类和啮齿类动物的骨髓细胞可分化为多种细胞类型,包括骨骼肌细胞、心肌细胞、神经细胞和肝细胞等,这些骨髓干细胞的可塑性研究,为肝细胞移植提供了新的供体来源.骨髓干细胞替代肝细胞进行移植具有来源丰富,费用相对低廉,对患者损伤小等优点,且自体骨髓干细胞移植可以完全避免移植排斥反应,同时,骨髓干细胞只有 5-15 μm,移植后不会发生栓塞等并发症.因此骨髓干细胞移植在治疗肝病以及解决供体肝脏来源短缺方面具有广泛的应用前景.本文就骨髓干细胞的移植途径做一综述. 相似文献
5.
目的:目前临床进行隧道法舌根射频治疗时,其作用参数的设置仍缺乏统一的标准,故通过计算机三维重建射频损伤区域,分析猪舌根射频损伤体积与射频能量、时间的关系,从中得出应用舌根隧道法射频治疗的最佳作用能级和作用时间。
方法:实验于2006-06/2007-05在上海交通大学耳鼻喉科研究所完成。将36只实验用猪以射频作用能级1,2,3,4,5,6随机分成6组,每组6头猪,各个猪舌的作用时间分别设置为2,5,10,15,20,25s。用Coblation射频发生仪及Reflex55刀头进行猪舌根射频操作。射频作用后的舌根组织行连续冰冻切片,苏木精-伊红染色后,进行序列组织切片的全貌二维图像采集,对拟重建的结构进行边界提取和图像分割。将提取分割图像导入Image-Pro Solution图像处理软件,利用3D Constructor插件进行三维重建,并根据设定参数进行体积计算。用SPSS10.0统计学软件对所测数据进行统计学分析。
结果:①作用能级固定时,舌根组织射频损伤体积随时间延长而增大,符合Logarithmic回归曲线。②作用时间固定时,舌根组织射频损伤体积随能级增大而增大,符合直线回归。③射频损伤体积随能量增大而增加亦符合Logarithmic回归曲线。④Coblation射频治疗系统在能级6时,在作用10s之前,损伤体积随作用时间增加而迅速增加,其后变化趋势平缓,超过20s后损伤体积无显著增加。
结论:①舌根区域射频治疗时,舌根组织射频损伤体积与时间或能量呈Logarithmic曲线相关,与能级呈直线相关。②Coblation射频治疗系统在能级6时,最佳作用时间范围为10-20s。 相似文献
6.
Anthony Stock MRCOG Wong Wai Ming MRCOG Michael Rogers FRCOG Allan MZ Chang PhD 《The Australian & New Zealand journal of obstetrics & gynaecology》1994,34(4):393-398
EDITORIAL COMMENT: We accepted this paper for publication because the authors have explored the possible value of ultrasound versus clinical assessment of fetal size to see whether they can predict the need for Caesarean section when the baby is large. In this study both the ultrasound and the clinical assessment were impressively accurate and fetal femur length was the most accurate of the ultrasound parameters in assessing fetal weight in predicting the need for Caesarean section. However, as the authors indicate, none of these methods of assessment of fetal size are recommended as an absolute indication for Caesarean section. Every obstetrician uses clinical assessment of the fetus when evaluating management of the patient but the need for clinical judgment remains.
Summary: One hundred and five women with singleton pregnancies and cephalic presentation were assessed. Fundal height and a clinical estimate of fetal weight were recorded. The fetal biparietal diameter, abdominal circumference and femur length were measured with ultrasound. Ultrasound estimated fetal weight was calculated using 3 different formulas (Shepard, Campbell and CUHK). The liquor volume was assessed using the amniotic fluid index.
Ultrasound was able to predict Caesarean section with more reliability than clinical assessment of fetal size or weight. The biparietal diameter, fundal height and amniotic fluid index were poor predictors of mode of delivery. The measurements which best predicted the mode of delivery were the fetal femur length and abdominal circumference. Femur length, but not abdominal circumference, was a statistically better predictor of Caesarean section than clinical estimation of fetal weight. There was no improvement in prediction using ultrasound estimated fetal weight. 相似文献
Summary: One hundred and five women with singleton pregnancies and cephalic presentation were assessed. Fundal height and a clinical estimate of fetal weight were recorded. The fetal biparietal diameter, abdominal circumference and femur length were measured with ultrasound. Ultrasound estimated fetal weight was calculated using 3 different formulas (Shepard, Campbell and CUHK). The liquor volume was assessed using the amniotic fluid index.
Ultrasound was able to predict Caesarean section with more reliability than clinical assessment of fetal size or weight. The biparietal diameter, fundal height and amniotic fluid index were poor predictors of mode of delivery. The measurements which best predicted the mode of delivery were the fetal femur length and abdominal circumference. Femur length, but not abdominal circumference, was a statistically better predictor of Caesarean section than clinical estimation of fetal weight. There was no improvement in prediction using ultrasound estimated fetal weight. 相似文献
7.
8.
Oliver Zschenker Kerstin Borgmann Thomas Streichert Ingo Meier Agnieszka Wrona Ekkehard Dikomey 《Radiotherapy and oncology》2006,80(2):236-249
BACKGROUND AND PURPOSE: The genetic profile as determined by microarray is considered to be an ideal marker of the individual radiosensitivity. However, it is still an open question, whether this profile has to be determined prior to or only after irradiation, since the expression of some genes is affected by irradiation. These changes are induced mainly due to a p53-dependent transactivation. MATERIALS AND METHODS: In this study gene expression profiles were measured for 3 lymphoblastoid cell lines differing in p53 status (p53 wt: TK6; p53null: TK6E6, p53mut: WTK1) measured either prior to or 3h after exposure to 2Gy. The gene expression profile was determined using the Affymetrix Human HG U133A GeneChip and for selective genes, variation in gene expression was validated by qRT-PCR. In addition, different assays were used to characterize the radioresponse of these three strains. RESULTS: The three strains were found to be different in all aspects of radiosensitivity studied. Cells with p53wt showed more apoptosis, slightly stronger arrest in G1, but less lethal aberrations and a lower viability when compared to cells with mutated p53, whereas cells absent in p53 are characterized by an intermediate response. The gene expression profile measured prior to irradiation already revealed huge differences. Significance analysis of microarrays (SAM) identified 141 genes that changed expression twofold or more with a false discovery rate (FDR) of 5.4%. When compared to p53null cell line with p53wt showed a twofold difference in up- or down-regulation in 28 genes. A much higher variation was even found when p53mut cells were compared with p53null cells with a twofold difference in even 123 genes. The respective genes were found to be involved mainly in apoptosis, cell cycle regulation, metabolisms and signalling but with only one gene relevant for DNA repair. Radiation was found to affect this profile solely for cells with p53wt with a twofold significant up-regulation in only five genes. For selective genes (BCL2, CASP1, CCND2, DDB2, XPC, RAD51C, SESN1, FUCA1, CDKN1A, MDM2, XPC) array data were confirmed by qRT-PCR. CONCLUSION: The result, that the gene expression profile of lymphoblastoid cells differing in p53 status already displayed clear differences when measured prior to irradiation with only few changes after irradiation, which are solely seen for p53wt cells, suggests, that the differences in radiosensitivity observed for these cells are primarily determined by the variation in expression profile present already prior to irradiation. 相似文献
9.
R M Wrona 《American journal of public health》1979,69(7):673-679
Thirty-nine cases of hyperphenylalaninemia from four diagnostic-treatment centers in Ohio were investigated in a retrospective cohort analysis. None of the centers is included in the PKU Collaborative Study. Epidemiologic analysis showed that early treatment is effective and that degree of dietary control (within limits) does not affect the probability of retardation or borderline retardation. Regression analysis supported the critical period hypothesis rather than the maximum concentration theory. Exposure to serum phenylalanine of 23--27 mg./dl. corresponds to 50 per cent probability retardation. The clinical epidemiologic approach offers an alternative methodology for designing collaborative studies. 相似文献
10.
Tryptamine-4,5-dione (1) is formed by oxidation of 5-hydroxytryptamine by reactive oxygen and reactive nitrogen species. Dione 1 is a powerful electrophile that can covalently modify cysteinyl residues of proteins and deactivate key enzymes. Thus, 1 has been suggested to play a role in the degeneration of serotonergic neurons in brain disorders such as Alzheimer's disease or evoked by amphetamine drugs. However, if formed in the brain, it is also likely that 1 would react with low molecular weight thiols such as cysteine (CySH) and glutathione (GSH). The resulting metabolites might not only contribute to the degeneration of serotonergic neurons but also, perhaps, serve as biomarkers of such neurodegeneration. In this investigation, it is shown that in oxygenated buffer at pH 7.4 dione 1 reacts with CySH and other low molecular weight sulfhydryls such as GSH, N-acetylcysteine, and cysteamine to form, first, the corresponding 7-S-thioethers of the dione. However, unlike the glutathionyl and N-acetylcysteinyl conjugates of 1, the 7-S-cysteinyl conjugate is very unstable at pH 7.4 forming a number of novel products, the nature of which are dependent on the relative concentrations of 1 and CySH. These products have been isolated, and spectroscopic and other evidence is provided in support of their proposed chemical structures. 相似文献