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211.
Objective: Based on the findings that erythropoietin (EPO) has been proved to be a multiple functional cytokine to attenuate ischemia–reperfusion (I/R) injury in various organs such as brain, heart, and kidney in animals, this experiment was designed to evaluate the effect of pretreatment with recombined human erythropoietin (rhEPO) on I/R-induced lung injury. Methods: Left lungs of rats underwent 90 min of ischemia and then were reperfused for up to 2 h. Animals were randomly divided into three experimental groups as sham group, I/R group, and rhEPO + I/R group (a single dose of rhEPO was injected intraperitoneally 3000 U/kg 24 h prior to operation). Lung injury was evaluated according to semi-quantitive analysis of microscopic changes, tissue polymorphonuclear neutrophils (PMNs) accumulation (myeloperoxidase (MPO) activity), and pulmonary microvascular permeability (Evan's blue dying method). Peripheral arterial and venous blood samples were obtained for blood–gas analysis after 5 min occlusion of right lung hilus at the end of reperfusion. The serum concentration of tumor necrosis factor (TNF)- was also measured by the method of enzyme-linked immunosorbent assay. Results: Histological injury scoring revealed significantly lessened lung alveolus edema and neutrophils infiltration in the rhEPO pretreated group compared with I/R group (p < 0.05). The rhEPO pretreated animals exhibited markedly decreased lung microvascular permeability (p < 0.05) and myeloperoxidase activity (p < 0.05). Blood–gas analysis demonstrated that the pretreated animals had significantly ameliorated pulmonary oxygenation function (p < 0.05). The serum concentration of tumor necrosis factor- in rhEPO pretreated group was markedly decreased compared with that of I/R group (p < 0.05). Conclusions: Pretreatment with rhEPO appears to attenuate I/R-induced lung injury. This function is partly related with the capacity that rhEPO inhibits the accumulation of polymorphonuclear neutrophils in lung tissue and decreases the systematic expression of tumor necrosis factor-.  相似文献   
212.
BACKGROUND: Some skin carcinomas may be very aggressive. Increased expression of the protein p53 has been associated with tumor aggressiveness. In this study, p53 expression was evaluated in basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) with skull base invasion, and was compared to tumors with good outcome. STUDY DESIGN AND SETTING: Expression of p53 was immunohistochemically analyzed and it was reported as present or absent in 24 BCC and 11 SCC with skull base invasion. Control group (good outcome) included 23 BCC and 10 SCC. RESULTS: Expression of p53 was noted in 70.83% of BCC with skull base invasion, compared to 43.48% in the control group (P = 0.058). Regarding SCC, p53 positivity was noted in only 9.09% of SCC with skull base invasion, compared to 40.00% in the control group (P = 0.149). CONCLUSIONS: In this study, p53 expression was more common among BCC with skull base invasion, compared to controls with good outcome, and the difference was considered marginally significant. This proportion was reversed in SCC, but the difference was not statistically significant. EBM rating: B-3b.  相似文献   
213.
An important aspect of preventive medicine is to identify subjects at risk as soon as possible, so preventive strategies can be introduced at early ages. The justification for this strategy is twofold: firstly, the assumption that children maintain a particular high value of a risk factor for disease throughout life; and secondly, the assumption that lowering the level of the risk factor in early life will have a greater impact on the disease than will risk factor changes in later life. In epidemiology the analysis of such factors over time is referred to as tracking. Tracking analysis has been applied to risk factors for cardiovascular diseases (CVD) in pediatric years. The aims of this study were: I) to analyze the stability of biological risk factors [high blood pressure (BP), high percentage of fat mass (%FM) and high total cholesterol (TC)] and lifestyle risk factors [low physical activity index (PAI)] in isolation; and II) to analyze the stability of zero, one, two or three biological risk factors. There were two evaluations in 692 children and adolescents (325 boys and 367 girls), aged between 8 and 15 years. The quartiles, adjusted for age and gender, were the criterion used to identify subjects with biological risk factors (fourth quartile) and with lifestyle risk factors (first quartile) for CVD. The stability was calculated through the relative frequency of subjects who maintained or changed quartile between the two evaluations. There is stability for biological risk factors as well as for behavioral and/or lifestyle risk factors. However, the highest stability is seen in biological risk factors.  相似文献   
214.
215.
国产氟康唑对小鼠隐球菌病的疗效   总被引:1,自引:1,他引:0  
以5×103cfu/鼠的新型隐球菌给小鼠脑室感染(ic)1h后,分别口服氟康唑(Flu)5和10mg/(kg·d)或酮康唑(Ket)50和100mg/(kg·d),bid×9d。对ic小鼠连续观察40天的存活率和平均存活时间,Ful分别为50%~70%和8~15天,Ket是30%~40%和5~9天。由小鼠侧尾静脉注射106cfu/鼠新型隐球菌3天后产生的全身感染,分别给小鼠口服Flu2.5~10mg/(kg·d)或Ket25~100mg/(kg·d),bid×9d。感染24、28和32天的PD50Flu是2.7、3.5和6.7mg/kg,Ket为28.4、70.4和83mg/kg;Flu和Ket的平均存活时间分别是23~34天和20~31天。在上述两种实验模型中分离脑和肺做细菌培养,Flu均与对照和50mg/(kg·d)的Ket比较,对ic10天及静脉注射感染13天的小鼠,口服5和10mg/(kg·d)或2.5~10mg/(kg·d)Flu均显著抑制新型隐球菌生长。  相似文献   
216.
合成了四种结构类型的苯并恶唑化合物共15个:测试了它们的红外吸收光谱,以及它们在DMF中的紫外吸收、荧光发射和激光发射光谱。苯基取代物的荧光量子产率在0.64~0.66,无激光性能。其余的化合物荧光量子产率都大于0.70,在最大吸收波长下的激光转换效率为2.5~5.9%。  相似文献   
217.
Non-invasive ambulatory recordings of blood pressure and heart rate were performed using a Spacelabs device during day and night periods in patients with Parkinson's disease with (n = 19) or without orthostatic hypotension (n = 19). In patients with orthostatic hypotension, the average systolic and diastolic blood pressure during the night (137 ± 5/80 ± 3 mmHg) was higher (p < 0.05) than during the day period (121 ± 3/76 ± 2 mmHg). In patients without orthostatic hypotension, a decrease in blood pressure was recorded during the nocturnal period. In patients with orthostatic hypotension, the blood pressure variability was higher (p < 0.05) during the day (systolic: 14.6 ± 1.3%; diastolic: 16.5 ± 1.0%) than during the night (systolic: 9.1 ± 0.8%; diastolic: 10.8 ± 1.1%). The blood pressure load (percentage of values above 140/90 mmHg) during the night was significantly higher than during the day for both systolic (41.2 ± 8.1 vs. 19.6 ± 4.7%) and diastolic blood pressure (24.9 ± 6.9 vs. 16.3 ± 4.9%). There was a decrease in heart rate in both groups during the night. A fall of 25 mmHg or more in systolic blood pressure after meals occurred in ten patients with orthostatic hypotension and in one patient without orthostatic hypotension. These results indicate that orthostatic hypotension in Parkinson's disease is associated with specific modifications of ambulatory blood pressure including loss of circadian rhythm of blood pressure, increased diurnal blood pressure variability and post-prandial hypotension.  相似文献   
218.
Immunoreactivity to Fos protein (Fos-IR) was detected in rat hypothalamic neurons within 1 h of onset of hemorrhage by withdrawing 4-5 ml of blood, which lowered the arterial blood pressure to 50-70 mm Hg. About 70% of vasopressin (AVP)-containing neurons in the supraoptic nucleus (SON) and 20% in the paraventricular nucleus (PVN) expressed Fos-IR. In contrast, 5% of oxytocin (OXY)-containing neurons in the SON and < 1% in PVN were Fos-IR. Intravenous infusion of the vasodilating agent, nitroprusside, which lowered the blood pressure to levels comparable to that attained by hemorrhage, induced Fos-IR in greater than 65% of AVP-containing neurons in the SON, while relatively few AVP neurons in the PVN were Fos positive. These results suggest that hemorrhage or hypotension preferentially induces c-fos expression in supraoptic AVP-containing neurons.  相似文献   
219.
用YAG、CO_2激光按不同功率照射家兔眼,观察对角膜、虹膜、晶状体的损伤和修复过程,探索两种激光对角膜的最小损伤和使其穿孔的有效功率。结果发现:YAG激光用230~250mW(1~2秒)时,可使角膜上皮呈灰白色混浊,1~2W(5~6秒)时角膜穿孔;CO_2激光用340~380mW(0.2~2秒)时,同样使角膜上皮灰白色混浊,1.3~1.4W(1秒)时角膜穿孔,在功率、照射时间、光斑相同的条件下,CO_2激光对角膜损伤重,YAG激光则对虹膜、晶状体损伤重。  相似文献   
220.
脂肪栓塞综合征:附19例报告   总被引:2,自引:0,他引:2  
脂肪栓塞综合征是创伤或骨折的严重并发症,死亡率高,通过对19例临床观察分析及复习文献,提出对本征诊断有重要意义的4项标准:(1)“暴风雪”样肺片;(2)皮肤或粘膜有出血点;(3)低氧血症;(4)血小板减少,并认为应用高压氧治疗本征是一种有效的方法。  相似文献   
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