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21.
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
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23.
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
24.
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
25.
26.
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
27.
Ahmed M. Abu El-Asrar Eman S. Kahtani Khalid F. Tabbara 《Documenta ophthalmologica. Advances in ophthalmology》1995,89(4):313-320
In this report we describe, herewith, a patient with primary pigmentary dystrophy of the retina (retinitis pigmentosa) associated with unilateral retinal arteriovenous communication and exudative retinal detachment. The patient had complete resolution of the retinal detachment following laser photocoagulation treatment. Such association has not been previously reported. 相似文献
28.
Kamran Ahmed Ashok Kelshiker Christopher Jenner 《Primary care respiratory journal》2007,16(4):249-251
AIMS AND OBJECTIVES: To screen for, and to treat, depression in COPD patients in a general practice surgery, and to test the feasibility of the screening method. METHODS: We sent The Beck Depression Inventory (BDI) Short-Form Questionnaire to all patients on the COPD register (n=69) by post, excluding those already diagnosed with depression (n=3). We sent appointments to all responders with moderate to severe depression and offered them treatment including antidepressants and pulmonary rehabilitation if the diagnosis was confirmed. RESULTS: Of the 66 patients to whom we sent questionnaires, 43 were returned completed and 13 of these had significant depression (30%). 10 of these patients were contactable and attended for review. The diagnosis of depression was confirmed in all 10 cases. Treatment options were discussed; five chose antidepressant medication, three chose pulmonary rehabilitation and two declined treatment. CONCLUSION: We identified and treated a significant number of depressed COPD patients in a general practice setting using this screening method. This method could have wider applications for screening, although further trials are needed. 相似文献
29.
30.
Jerzy Slowinski Jake Dominik Ryan J. Uitti Zeshan Ahmed Dennis D. Dickson Zbigniew K. Wszolek 《Neuropathology》2007,27(1):73-80
We present a case of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP‐17) harboring the N279K mutation in the MAPT gene from the family known as pallido‐ponto‐nigral degeneration (PPND). This 49‐year‐old man was followed for 17 years. He presented at age 41 years with left leg stiffness and en‐bloc turning. During the course of his illness he developed a constellation of symptoms including parkinsonism, pyramidal signs, vertical gaze palsy, dysphagia, dystonia, personality and cognitive dysfunction, weight loss and mutism. Gross neuropathological examination showed mild atrophy of the cerebral cortex, hippocampal formation, amygdala, thalamus, subthalamic nucleus and depigmentation of the substantia nigra. Microscopy revealed neuronal loss and gliosis in the same regions. Tau immunohistochemistry showed pretangles, numerous threads, grain‐like structures and oligodendroglial tau‐positive inclusions (“coiled bodies”). In the spinal cord the tau pathology was more abundant in gray than white matter. Pretangles and threads were present in the anterior and, to a lesser extent, in the posterior horns. FTDP‐17 should be suspected in patients with a history of familial parkinsonism combined with behavioral and cognitive changes, onset before age 65 years and an aggressive clinical course. 相似文献