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191.
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Objective: To investigate the anti-inflammatory effect of erythropoietin (EPO) pretreatment on cardiomyocytes exposed to hypoxialreoxygenation injury (H/R) and explore the possible mechanism.
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect.  相似文献   
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Background/aims  Surgical resection of choledochal cysts (CC) has become standard treatment. However, surgery is not universally recommended in early infancy and/or asymptomatic patients. In order to investigate the optimal timing of CC excision, we analyzed clinicopathological data and surgical results from different age groups. Material and methods  This retrospective review included 107 patients (77 females, 30 males) who underwent CC resection at the National Taiwan University Hospital between January 1988 and December 2005. Patient demographic, clinical, and surgical data were collected and analyzed. Results  The patients were divided into three groups according to age at the time of surgery: <1 year old (group I, n = 26), 1−16 years old (group II, n = 48), and >16 years old (group III, n = 33). About two thirds of the patients in group I had jaundice, while abdominal pain related to inflammation was the commonest symptom in groups II and III. Group I suffered significantly fewer surgical complications and less severe liver fibrosis than groups II or III. Conclusion  CC surgery in infancy and in asymptomatic patients is safe and may prevent the complications of this condition. The results support a recommendation for early excision.  相似文献   
195.
陈为国 《医疗设备信息》2006,21(10):110-111
本文将对呼吸机以下两种常见故障进行简要分析:①呼吸机在抢救病人过程中出现自动切断电源②呼吸机气道口湿度报警。  相似文献   
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Functional magnetic resonance imaging (fMRI) based on blood oxygen level-dependent (BOLD) contrast has become an invaluable tool in the assessment of in vivo neuronal activation. Quantification of the BOLD response is determined by the hemodynamic and metabolic changes that occur in response to brain stimulation. However, these changes may vary by changes in insulin, a hormone known to be vasoactive in some tissues. To determine if insulin has an effect on fMRI, we measured the BOLD response to a visual stimulus in five normal volunteers in which insulin was first suppressed and then brought to a high physiological concentration. In addition, we also examined the effect of insulin on activation of the visual cortex as measured by the visual-evoked potential (VEP). We found that the BOLD response measured in the presence of insulin (serum insulin=236+/-29 pmol/L) was significantly lower (P<0.001) than that measured in its absence (serum insulin=8+/-2 pmol/L). Insulin was without effect on P100 amplitude or latency acquired in the presence or absence of insulin in 28 subjects using the same stimulus as that used for the fMRI experiments. Our observations suggest that insulin may have effects on cerebral blood flow and/or metabolism that affect the BOLD signal that are independent of its effects on neuronal activation identified by event related potentials (ERP). These findings highlight the complexity that must be considered when interpreting differences in fMRI responses between groups of subjects that differ in insulin concentration and/or insulin sensitivity.  相似文献   
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199.
Four poorly differentiated malignant lesions occurred in a 60-year-old Chinese male in the nasal cavity, submandibular gland, a lymph node in the neck, and the mandible. These malignant lesions developed within an 8-year period and each showed distinctive histological features. Among these malignant lesions, the neoplasm in the submandibular gland presented variegated histological and immunohistochemical (IHC) features and posed a diagnostic challenge in interpretation. Based on microscopic and IHC findings, we believe the diagnosis of teratocarcinosarcoma is justified for the submandibular neoplasm and the metastasis in the lymph node. The pathological features and diagnoses of these malignant lesions are discussed.  相似文献   
200.
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