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71.
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
72.
Histological, histochemical and electron microscopic changes of the placenta induced by maternal exposure to hyperthermia in the rat. 总被引:3,自引:0,他引:3
R Padmanabhan N M Al-Menhali I Ahmed H H Kataya M A Ayoub 《International journal of hyperthermia》2005,21(1):29-44
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
73.
74.
M. Donnelly O. Owonikoko N. Khan W. J. Gaine 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(2):179-180
We report a case of acromio-clavicular joint septic arthritis, a very rare complication of an innocuous finger injury. 相似文献
75.
76.
Kulbir S. Walia MD ; Daniel E. Muser MD ; Shariq S. Raza MD ; Tricia Griech MSPT ; Yasin N. Khan MD 《Pain practice》2004,4(4):303-306
Abstract: We present a case of a 13-year-old boy who developed signs and symptoms of neuropathic pain/early Complex Regional Pain Syndrome (CRPS) Type I, formerly known as Reflex Sympathetic Dystrophy (RSD), after spraining his ankle while wrestling. Aggressive pain control, using medications and sympatholytic blocks, with physical therapy and rehabilitation, led to the resolution of his painful condition. This prevented the disease from possibly progressing to a full-blown case of CRPS I (RSD) that is very challenging to treat. 相似文献
77.
Hassan Chamsi-Pasha Alaa Abdulmoneim Waqar H Ahmed Khaled F Al-Shaibi Aref Ajam Hassan Bakhamees Abdullah K Ashmeg 《Journal of the American Society of Echocardiography》2004,17(1):70-72
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
78.
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
79.
80.
K elZaki M E Ahmed A M elHassan M A Yousif A H Fahal 《The Journal of tropical medicine and hygiene》1991,94(3):206-209
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