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1.
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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The effect of radiotherapy and adjuvant levamisole immunotherapy on the lymphocyte subpopulations was investigated. Comparisons were made between the groups receiving levamisole, those receiving placebo and normal healthy controls. Results of a thirty-month follow-up are reported. Radiotherapy caused leukopenia and lymphopenia affecting all the subsets (T, B, TG, and TM), T lymphocytes were affected to a greater extent. This study demonstrates that levamisole does hasten the restoration of T lymphocytes, with the TM lymphocytes showing a faster repopulation in comparison to the TG lymphocytes.  相似文献   
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Lymphoid and haemopoietic malignancies as a group constitute one of the important cancers in India, as elsewhere in the world. While information on incidence and mortality of these cancers, and that on survival, are available from most developed countries, there are very few reports describing this experience in developing ones. Population-based cancer registration commenced in Bangalore, India, in January 1982, under the auspices of the Indian Council of Medical Research. This source provides fairly complete and reliable incidence data, but, in order to obtain mortality and survival information, active follow-up involving visits of homes of patients was undertaken. Between 1982 and 1989, 1397 cases of lymphoid and haemopoietic malignancies were registered in the Bangalore cancer registry, giving an age-adjusted incidence rate of 7.7 and 4.8 per 100,000 in males and females respectively. Active follow-up provided mortality/survival information in 1267 or 90.7% of these cases. The overall observed 5-year survival for these cancers combined (both sexes) was 26%, and relative survival 28.4%. The 5-year survival rate was lower in all the individual lymphomas and leukaemias as compared with similar reports from the developed countries. Survival in Hodgkin's disease was influenced by clinical stage and age at presentation.  相似文献   
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We have studied the effect of clonidine pretreatment on cardiovascular responses to various stimuli during craniotomy. Fifty-eight patients (ASA Class I-II), scheduled for supratentorial surgery, were randomly given either oral clonidine, mean dose 3.6 micrograms/kg (n = 28), or oral diazepam, 0.2 mg/kg (n = 30), ninety to one hundred minutes before surgery. Anaesthesia was induced with thiopentone and maintained with nitrous oxide:oxygen, pentazocine and halothane. Pancuronium was used as a neuromuscular blocker. Mean arterial pressure and heart rate were recorded before and after several stimuli. In the clonidine group hypertensive response was significantly less on laryngoscopy (6.5% increases versus 11.2% in the diazepam group), intubation (9.2% versus 16.5%), Mayfield clamp application (14.5% versus 29.91%) and after skin infiltration with lignocaine-adrenaline solution (2.95% versus 5.42%). Heart rate response to laryngoscopy, intubation and skin infiltration was also significantly attenuated in the clonidine group. The sleep dose of thiopentone was smaller in patients pretreated with clonidine. Patients in the diazepam group required more medical intervention. No adverse effect occurred in any patient.  相似文献   
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