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Helms  CA; Kaban  LB; McNeill  C; Dodson  T 《Radiology》1989,172(3):817-820
Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement.  相似文献   
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叶托马尾藻中的生物活性甾体成分   总被引:4,自引:0,他引:4  
目的 研究褐藻叶托马尾藻的活性成分。方法 采用稻瘟霉模型生物活性追踪方法,应用多种色谱手段和光普分析方法分离和鉴定化合物。结果 鉴定了7个甾体类化合物,分别为岩藻甾醇(Ⅰ),24-乙基-4,24(28)-胆甾二烯-3-酮(Ⅱ),24-乙基-4,24(28)-胆甾二烯-3,6-二酮(Ⅲ),马尾藻甾醇(Ⅳ),24R,28R-和24S,28S-环氧-24-乙基胆甾醇(Ⅴ),胆甾醇-24-酮(Ⅵ)和豆甾醇(-3-O-葡萄糖苷(Ⅶ)。结论 Ⅱ-Ⅶ为首次从该海藻中分离得到,Ⅰ和Ⅲ-Ⅵ具有诱导稻瘟霉菌比来形活性。  相似文献   
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BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha with improved solution properties. We show here that it mobilizes stem cells into the peripheral blood. We investigated the mobilizing effects of BB-10010 on the numbers of circulating 8-day spleen colony-forming units (CFU-S8), CFU-S12, and progenitors with marrow repopulating ability (MRA). A single subcutaneous dose of BB-10010 caused a twofold increase in circulating numbers of CFU-S8, CFU-S12, and MRA 30 minutes after dosing. We also investigated the effects of granulocyte colony-stimulating factor (G- CSF) and the combination of G-CSF with BB-10010 on progenitor mobilization. Two days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA progenitors by 25.7-, 19.8-, and 27.7-fold. A single administration of BB-10010 after 2 days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA even further to 38-, 33-, and 100- fold. Splenectomy resulted in increased circulating progenitor numbers but did not change the pattern of mobilization. Two days of treatment with G-CSF then increased circulating CFU-S8, CFU-S12, and MRA by 64-, 69-, and 32-fold. A single BB-10010 administration after G-CSF treatment further increased them to 85-, 117-, and 140-fold, respectively, compared with control. We conclude that BB-10010 causes a rapid increase in the number of circulating hematopoietic progenitors and further enhances the numbers induced by pretreatment with G-CSF. BB- 10010 preferentially mobilized the more primitive progenitors with marrow repopulating activity, releasing four times the number achieved with G-CSF alone. Translated into a clinical setting, this improvement in progenitor cell mobilization may enhance the efficiency of harvest and the quality of grafts for peripheral blood stem cell transplantation.  相似文献   
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Introduction: Radiofrequency ablation of atrial fibrillation (AF) is associated with energy delivery on the posterior left atrial (LA) wall with small but significant risk of life-threatening complications. Anatomy of LA walls has been described, but wall thickness in patients with AF has not been studied systematically. The aim of the present study was to describe LA posterior wall thickness in patients with and without history of AF.
Methods and Results: Heart mass and LA wall thickness was measured during 298 consecutive autopsies (142 male, age 61 ± 17 years). LA posterior wall was measured at three levels: between the superior pulmonary veins (SPV), in the center of the posterior LA wall (CPV), and between the inferior pulmonary veins (IPV). Information about AF history was obtained from medical records. Fifty-nine subjects (20%) had documented AF. They were older than subjects without AF (74 ± 10 years vs 58 ± 17 years, P < 0.0001) and had greater heart mass (522 ± 114 g vs 389 ± 99 g, P < 0.0001). LA posterior wall thickness increased from the most superior to the most inferior measured level (2.3 ± 0.9 mm vs 2.5 ± 1.0 mm vs 2.9 ± 1.3 mm for SPV, CPV, and IPV, respectively; P < 0.001). Subjects with AF history had thinner LA posterior wall at CPV and IPV compared with those without AF.
Conclusions: LA posterior wall thickness is described on a large series of consecutive autopsies. LA posterior wall is found to be generally thinner in patients with history of AF. Study results have clinical implications for understanding complication risk and improvement of safety of AF ablation procedures.  相似文献   
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BACKGROUND: An increasing number of apheresis machines are becoming available for peripheral blood progenitor cell (PBPC) collection in children. STUDY DESIGN AND METHODS: At the Children's Hospital of Florence (Italy), three apheresis machines were evaluated: MCS 3P (Haemonetics) (10 procedures in 4 patients, aged 10–12 years, weight 23.5-64 kg), Spectra, (COBE) (8 procedures in 3 patients, aged 4–17 years, weight 19–59 kg), and AS104 (Fresenius) (24 procedures in 9 patients, aged 2–16 years, weight 13.6-60 kg). For PBPC quantitative analysis, CD34 cytofluorimetry was employed. Relevant variables analyzed included efficiency of CD34+ cell extraction and enrichment, mononuclear cell purity and red cell contamination of the apheresis components, and platelet count decreases after leukapheresis. RESULTS: No significant differences in CD34+ cell-extraction abilities were found. However, the AS104 provided consistently purer leukapheresis components in terms of mononuclear cell and CD34+ cell enrichment (441 +/− 59%, vs. 240 +/− 35% and 290 +/− 42% for MCS 3P and Spectra, respectively). Postapheresis platelet counts dropped the least with the AS104. The smallest patient who underwent apheresis with MCS 3P (the only machine working on discontinuous flow and hence with greater volume shifts) weighed 23.5 kg and tolerated the procedure well, with no signs of hemodynamic instability. No significant complications were observed. CONCLUSION: All machines seem to have comparable PBPC extraction efficiency, but the AS104 seems to give the component with the greatest PBPC enrichment. This feature might be relevant for further ex vivo cell processing (CD34+ cell selection, expansion, and so on).  相似文献   
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We report the case of a seven‐yr‐old Caucasian girl who presented with progressive deterioration of renal function 13 months after HSCT for myelodysplastic syndrome. BK virus nephropathy was suspected and confirmed. After reduction of immunosuppression and treatment with IVIG, leflunomide, ciprofloxacin, and cidofovir, clearance of BK virus from blood was achieved, and further progression or renal failure was prevented. We believe that BK virus nephropathy should be considered in cases of renal function deterioration in all immunocompromised patients.  相似文献   
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Diabetic kidney disease (DKD) is the most common cause of ESRD in the United States. Podocyte injury is an important feature of DKD that is likely to be caused by circulating factors other than glucose. Soluble urokinase plasminogen activator receptor (suPAR) is a circulating factor found to be elevated in the serum of patients with FSGS and causes podocyte αVβ3 integrin-dependent migration in vitro. Furthermore, αVβ3 integrin activation occurs in association with decreased podocyte-specific expression of acid sphingomyelinase-like phosphodiesterase 3b (SMPDL3b) in kidney biopsy specimens from patients with FSGS. However, whether suPAR-dependent αVβ3 integrin activation occurs in diseases other than FSGS and whether there is a direct link between circulating suPAR levels and SMPDL3b expression in podocytes remain to be established. Our data indicate that serum suPAR levels are also elevated in patients with DKD. However, unlike in FSGS, SMPDL3b expression was increased in glomeruli from patients with DKD and DKD sera-treated human podocytes, where it prevented αVβ3 integrin activation by its interaction with suPAR and led to increased RhoA activity, rendering podocytes more susceptible to apoptosis. In vivo, inhibition of acid sphingomyelinase reduced proteinuria in experimental DKD but not FSGS, indicating that SMPDL3b expression levels determined the podocyte injury phenotype. These observations suggest that SMPDL3b may be an important modulator of podocyte function by shifting suPAR-mediated podocyte injury from a migratory phenotype to an apoptotic phenotype and that it represents a novel therapeutic glomerular disease target.  相似文献   
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