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91.
Patients with dilated stenoses and recanalized occlusions were evaluated to assess the initial and long-term results of percutaneous transluminal angioplasty (PTA) in the femoropopliteal artery. The follow-up period was at least 1 year. The initial success rate was 84% (128/164). The initial results were influenced by the radiologist's experience, catheter selection, and type of lesion. The 5- and 7-year cumulative patency rates were 70% and 60%. There was no difference in long-term patency between initially successful stenoses and short (less than 3 cm) occlusions. Both the morphology and location of the stenotic lesion influenced the long-term results. Although many factors influence the initial and long-term success rate, results of this study justify PTA in the femoropopliteal artery. Patients with localized stenoses and short occlusions are best suited for this treatment.  相似文献   
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Intraoperative ultrasound examination of the brain   总被引:5,自引:0,他引:5  
In a preliminary demonstration of cranial intraoperative real-time ultrasound, both supratentorial and posterior fossa scans displayed the pertinent anatomy. A grade III astrocytoma was visualized on the supratentorial scan as well. Ultrasound may be valuable for surgical planning and biopsy procedures because of its reliable depiction of intracranial anatomy and ease of use.  相似文献   
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Serotonin is involved in the development of neural circuits modulating emotional behavior. The short allele (s) of a polymorphism (5-HTTLPR) of the serotonin transporter gene is a risk factor for psychopathology in the presence of environmental stressors. Maternal smoking is associated with growth restriction of the human fetal brain and adverse effects of nicotine on the developing serotonin system have been documented. We hypothesized that maternal smoking interacts with both child and mother 5-HTTLPR genotype as a risk factor for later child emotional problems. In a sample of n?=?1,529 mother-child dyads, smoking habits were assessed by questionnaires during pregnancy. Child emotional problems were measured by the Child Behavior Checklist at the child's age of 3 years. Maternal smoking during pregnancy significantly increased the risk for emotional problems in children carrying the s-allele; β?=?0.24, P?=?0.03 (mother-report), and β?=?0.46, P?=?0.001 (father-report). In children heterozygous at 5-HTTLPR and exposed to maternal prenatal smoking (n?=?79) risk of emotional problems increased with each additional s-allele the mother carried. The associations between 5-HTTLPR and child emotional problems were not moderated by paternal prenatal smoking. These findings imply that the vulnerability for emotional problems in s-allele carriers may already originate in fetal life.  相似文献   
97.
2010年8月,美国心脏病学会基金会(ACCF)、美国心脏学会(AHA)共同发布了美国食品药品管理局(FDA)关于氯吡格雷的"盒装警告",主要针对医师和患者提出建议,其内容包括:通过检测药物基因型以明确患者氯吡格雷的代谢变化,患者不良反应的风险,基因多态性对氯吡格雷的代谢及临床影响。  相似文献   
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Here, we report that cytokine-induced (granulocyte colony-stimulating factor and IL-8) hematopoietic stem cell (HSC) and hematopoietic progenitor cell (HPC) mobilization is completely inhibited after low-dose (0.5 Gy) total-body irradiation (TBI). Because neutrophil granular proteases are regulatory mediators in cytokine-induced HSC/HPC mobilization, we considered a possible role for protease inhibitors in the induction of HSC/HPC mobilization. Bone marrow (BM) extracellular extracts that were obtained from murine femurs after 0.5 Gy of TBI contained an inhibitor of elastase. Also, after low-dose TBI, both Serpina1 mRNA and protein concentrations were increased in BM extracts, compared with extracts that were obtained from controls. The inhibitory activity in BM extracts of irradiated mice was reversed by addition of an Ab directed against Serpina1. To further study a possible in vivo role of Serpina1 in HSC/HPC mobilization, we administered Serpina1 before IL-8 injection. This administration resulted in an almost complete inhibition of HSC/HPC mobilization, whereas heat-inactivated Serpina1 had no effect. These results indicate that low-dose TBI inhibits cytokine-induced HSC/HPC mobilization and induces Serpina1 in the BM. Because exogenous administration of Serpina1 inhibits mobilization, we propose that radiation-induced Serpina1 is responsible for the inhibition of HSC/HPC mobilization. Also, we hypothesize that cytokine-induced HSC/HPC mobilization is determined by a critical balance between serine proteases and serine protease inhibitors.  相似文献   
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Androgens are modulators of skeletal muscle adaptation and regeneration processes. The control of satellite cell activity is a key mechanism during this process. In this study, we analyzed the ability of dihydrotestosterone (DHT) and anabolic steroids to induce and modulate the differentiation of C2C12 myoblastoma cells toward myotubes. C2C12 cells were dose-dependently treated with DHT and anabolic steroids. The time-dependent effects on differentiation were measured and correlated with the expression of genes involved in the regulation of satellite cell activity. The distribution of C2C12 cells within the cell cycle was measured by flow cytometry and differentiation by creatine kinase (CK) activity. Gene expression was analyzed using quantitative real-time PCR and confocal microscopy. The treatment with DHT and anabolic steroids resulted in a stimulation of C2C12 cell proliferation and CK activity. The antiandrogen flutamide was able to antagonize this effect. The expression of the androgen receptor, SOX8, SOX9, Delta, Notch, myostatin, and paired box gene7 (Pax7) was modulated by androgens. The treatment with DHT and anabolic steroids resulted in a strong stimulation of myostatin expression not only in undifferentiated cells but also in myotubes. The stimulation could be antagonized by flutamide. The expression of Pax7 was detectable in C2C12 cells early after treatment with DHT. Our results demonstrate that the key mechanisms of satellite cell differentiation are modulated by androgens. Androgens stimulate the proliferation of C2C12 cells, accelerate the process of differentiation, and increase the expression of myostatin in undifferentiated and differentiated cells. Our findings may have implications not only for the treatment of muscular diseases but also for the improvement of doping analytical methods.  相似文献   
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