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51.
Unattached fractions of the radon progeny 218Po and 214Pb, size distributions for both unattached 218Po and 214Pb, and attached 214Pb and 214Bi, along with condensation nuclei (aerosol-particle concentrations), were measured in the open air of the city of El-Minia, Egypt. The measurements were performed with a wire-screen diffusion battery and a low-pressure Berner cascade impactor using standard methodologies. The results for parameters of derived distributions demonstrate that the distributions for the former (unattached 218Po and 214Pb) are nearly similar. The diffusion equivalent diameters (df) of 218Po and 214Pb were determined to be 1.4 and 1.55 nm with relative geometric standard deviations (σg) of 1.65 and 2.1, respectively. The latter distributions (attached 214Pb and 214Bi) are nearly identical. Most of the activities were associated with the aerosol particles of the accumulation mode. The mean activity median aerodynamic diameters (AMAD) of 214Pb and 214Bi have the same value of 380 nm but the relative geometric standard deviation of the log-normal distribution of 214Pb shows a broader activity distribution than 214Bi (σg = 2.2 for 214Pb and σg = 2.05 for 214Bi).  相似文献   
52.
目的 探讨大鼠心肌缺血再灌注 (Ischemiareperfusion ,IR)不同时相的心肌细胞凋亡、caspase 3活性变化规律及caspase 3抑制剂Ac DEVD CHO的影响。方法 Wistar大鼠 12 2只 ,设立IR组 ,IR +Ac DEVD CHO组和假手术对照组并分设缺血 3 0min后再灌注 1、3、6、12、2 4h 5个时相点 ;以缺口末端标记法 (TUNEL)标记凋亡细胞 ,用荧光分析法检测caspase 3活性 ,行TTC染色测定心肌梗死范围。结果 心肌细胞凋亡与caspase 3活性随心肌再灌注不同时相而变化 ,心肌细胞凋亡指数 (Apoptosisindex ,AI)与caspase 3活性于再灌注 12h最高 [AI :( 3 4 83± 9 3 5 ) % ;caspase 3活性 :( 1 3 4±0 2 ) ] ,其后基本维持在平台状态 ;心肌梗死范围随IR时间逐渐增加 ,至 2 4h仍未见下降趋势 ,三者间呈显著正相关 (P <0 0 5 )。IR +Ac DEVD CHO组上述指标虽也明显增高 ,但比IR组明显减小 (P <0 0 5 )。结论 Caspase 3激活及心肌细胞凋亡参与了心肌缺血再灌注损伤过程 ,Ac DEVD CHO减轻心肌缺血再灌注损伤可能部分与其抑制心肌细胞凋亡有关。  相似文献   
53.
Both clinical and experimental investigations have shown that maternal hyperthermia during critical stages of embryo development can induce malformations in the offspring. Studies of the effect of heat stress on the placental functions are limited to the ewes, but that on microscopic structure is unknown. In the present study, rats were exposed to 41 or 42 degrees C for 1 h on gestation day (GD) 9. The controls were sham treated. Fetuses and placentas were collected on GD 20. Intrauterine growth retardation (IUGR) and several craniofacial malformations were observed in the fetuses of the heat-treated group. The placentas of the 42 degrees C group were significantly lighter in weight than those of the control. Light microscopy (LM) revealed thickening, hyalinization and occasional lymphocytic infiltration of the decidua basalis. Giant cells were prominent and glycogen cells had degenerated, leaving behind large cysts in the basal (spongy) zone. Best's carmine stain with or without diastase indicated the reduction in number and degeneration of glycogen cells and cyst formation. The labyrinthine zone was relatively thin in comparison to that of the controls. Perivascular fibrosis and paucity of vascularization were other features of the placentas of the hyperthermia group. Electron microscopy (EM) revealed lipid droplet accumulation in the trophoblast, the presence of myelin bodies and an increased production of collagen in the basal zone. Perivascular fibrosis appeared to have contributed to placental barrier thickening. EM also revealed accumulation of glycogen and lipid droplets in the trophoblasts and fibrin secretion into the extracellular space of the labyrinthine zone. These data suggest that placental pathology possibly contributes to fetal growth retardation in maternally heat-stressed rat fetuses.  相似文献   
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A 24-year-old man presented with a 24-hour history of pain and numbness in his left arm. The patient's clinical presentation of peripheral embolism was corroborated by angiography. Echocardiographic study showed masses in both right and left atria. Pathologic specimen from the embolus confirmed the diagnosis of aspergillosis.  相似文献   
57.
Abstract Simultaneous bilateral avulsions of the tibial tuberosity are rare injuries. The authors found only five reported cases in the orthopedic literature. We add a further case of bilateral avulsions of the tibial tuberosity with the longest reported follow-up.  相似文献   
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This prospective study contains clinical and experimental parts. In the clinical study, 125 patients given intramuscular chloroquine for malaria were followed for 2 months in order to detect local injection site complications. Adequate local antiseptic conditions were ensured before giving the injection. Twenty-three patients (18.4%) had minimal local reaction in the form of redness, induration and/or a lump. No pyogenic abscess was noted in contrast to a previous report. In the second part of the study, an experimental animal (Green monkey) was given either chloroquine phosphate, Ampiclox or normal saline intramuscularly. The injection site was later biopsied and histologically examined. Intramuscular chloroquine was found to cause severe inflammatory reactions and muscle necrosis, whereas other injections had very minimal local effects. It is concluded that intramuscular chloroquine causes muscle necrosis which may lead to acute pyogenic abscess if minimal contamination takes place.  相似文献   
60.
止咳枇杷冲剂中枇杷叶和桔梗的薄层色谱鉴别研究   总被引:1,自引:1,他引:0  
研究止咳枇杷冲剂中枇杷叶和桔梗的薄层色谱鉴别方法。分别取枇杷叶和桔梗药材,制剂及阴性制剂的醋酸乙酯提取液,在硅胶板上前者以ψ(氯仿:甲醇:水)=2:2.25:1.5展开,后者以ψ(正已烷:氯仿:甲醇)=5:4:0.3展开,磷钼酸乙醇溶液显色,在两者供试吕色谱中与各自对照药材色谱相应位置上,分别有相同的蓝绿色特征斑点;阴性制剂色谱图中无此斑点,因此该方法可作为这两味中药的鉴别方法。  相似文献   
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