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51.
Histopathological Changes of the Placenta in Diabetes Induced by Maternal Administration of Streptozotocin during Pregnancy in the Rat 总被引:1,自引:0,他引:1
Abstract The objective of this investigation was to find out the histopathological changes of the placenta and to correlate them with fetal malformations and growth retardation in experimental diabetes. Diabetes was induced in Wistar rats at different stages of gestation by intraperitoneal injection of streptozotocin (STZ). The controls were either buffer treated or injected with STZ followed by 2–6 IU insulin until term. All fetuses and placentae were collected on day 20 of gestation. Fetuses of diabetic rats were significantly growth retarded. Maxillary hypoplasia, edema, gastroschisis, exencephaly and septal defects of the heart were the major malformations. Most of the experimental placentae weighed heavier relative to their body mass. Toluidine blue stained sections of the placentae revealed severe histological abnormalities. The unusually large sized placentae had extensive cystic degeneration, often with an increased population of leucocytes. Giant cells were very numerous. Perivascular fibrosis, persistence of fetal mesenchyme, edema, infarcts and vacuolisation were observed in the labyrinths. In the small placentae, the glycogen cells were fewer and the glycogen in them remained unutilized. Reduction of labyrinthine zone, hypovascularity, constriction of vessels, perivascular edema and platelet aggregation characterized these placentae. The placentae of externally malformed fetuses showed cystic degeneration; their labyrinths contained constricted and less extensive vascular network. Phagocytic giant cells, polymorphs and platelet aggregation were also marked. Placentae of externally normal looking fetuses also presented cystic degeneration, reduction in fetal vasculature, dilated maternal sinusoids and giant cell proliferation. Insulin treatment resulted in the preservation of most of the normal histology of the placenta which correlated well with the reduced fetal malformations. 相似文献
52.
The variations with age and blood pressure in the cyclic nucleotide phosphodiesterase activator content of rat aorta were studied. Activator content increased with age and was less in mineralocorticoid-hypertensive than in control rats. These variations were more pronounced in the particulate than in the soluble fraction of aorta. The data do not demonstrate any relationship between the activator level and blood pressure, but they suggest that the activator may modulate cyclic nucleotide metabolism in rat aorta. 相似文献
53.
ALI MEHDIRAD CHARLES LOVE STEVEN NELSON STEPHEN SCHAAL JANET COLLINS KATHY HUFFMAN 《Pacing and clinical electrophysiology : PACE》1997,20(7):1885-1886
A patient with an ICD accidentally grasped a power line and was electrocuted. He was unable to release the cable during electrocution though he remained conscious. After receiving a shock from his ICD. the powerline was released. ICD interrogation revealed inappropriate detection of alternating current and delivery of a shock. 相似文献
54.
B. H. ALI 《The Journal of pharmacy and pharmacology》1997,49(10):1003-1007
Because many diabetic patients in the United Arab Emirates use medicinal plants as a supplement to treatment with insulin or oral hypoglycaemic agents, the effect on plasma glucose, insulin and glucagon concentrations of simultaneous treatment of streptozotocin-diabetic rats with Rhazya stricta extract and glibenclamide has been examined. Treatment of control rats with the extract at oral doses of 0.5, 20 and 4.0 g kg? did not significantly affect the concentration of glucose, insulin or glucagon for up to 4 h after administration of the extract. The same doses in diabetic rats reduced the glucose level 1 h (2 and 4 gkg?) and 2h (4 gkg?) after administration of the extract. This was accompanied by significant increases in insulin concentration 1, 2 and 4 h after administration of the extract at doses of 2 and 4 gkg?. Glibenclamide (2.5, 5.0 and 10.0 mgkg?) dose-dependently reduced glucose and glucagon levels, and increased that of insulin in normal and diabetic rats. Simultaneous treatment of normal and diabetic rats with the plant extract (0.5, 20 and 5.0 gkg?) and glibenclamide (5.0 mg kg?) significantly exacerbated the effects on glucose, insulin and glucagon induced by the extract or by glibenclamide when given separately. When the plant extract was given at doses of 0.5, 2 and 4 g kg? per day for 6 consecutive days the glucose level was reduced by approximately 6, 8 and 30%, respectively. No significant effect was seen on the levels of cholesterol or protein. These results imply that co-administration of the extract with glibenclamide might adversely interfere with glycaemic control in diabetic patients. 相似文献
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56.
A method is presented for the assessment of residual curarizationafter the use of anti-depolarizing muscle relaxants which doesnot involve the necessity for establishing control observations.The ulnar nerve at the elbow was stimulated with a train offour pulses repeated intermittently. The muscle response tothis train of four stimuli was recorded and analyzed using threeratios of twitch height (or electromyographic responses). Ratio(a) was taken as the height of the first response of the trainto the height of the control response (i.e. the response beforemuscle relaxant was given), ratio (b) as the height of the secondresponse to the height of the first response, and ratio (c)as the height of the fourth response to the height of the firstresponse. There was a highly significant positive linear associationbetween ratio (a), which involves the use of a control response,and the other two ratios, (b) and (c), which do not involvea control response. 相似文献
57.
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59.
ALI N. ZAIDI M.D. JOHN P. CHEATHAM M.D. SUBHA V. RAMAN M.D. STEPHEN C. COOK M.D. 《Journal of interventional cardiology》2009,22(1):92-97
Background: Complications of transcatheter closure of atrial septal defects (ASDs) include pericardial effusion, tamponade, and even death. Transthoracic echocardiography in the adult is often limited by poor acoustic windows that lead to incomplete device assessment. Advances in multislice computed tomography (MSCT) provide an alternative modality to assess the anatomy of the Amplatzer Septal Occluder (ASO) device.
Objective: The purpose of this study was to determine the feasibility of MSCT in providing anatomic information in patients with persistent or recurrent symptoms after transcatheter closure of ASDs with ASO devices.
Methods: A retrospective analysis of adult patients who underwent ASO device implantation with subsequent MSCT imaging as a result of symptoms from June 2006 to May 2007 was performed. Data analysis included age, gender, size of ASO device, relationship of the device to surrounding structures, symptoms, and the length of time between device implantation and onset of symptoms.
Results: Eleven patients were identified with a mean age of 41 years. Patients presented with symptoms 1 week to 2.4 years after implantation. ASO size ranged from 8 to 36 mm. MSCT provided detailed information in all 11 cases regarding anatomic location of the device with respect to surrounding structures. Nonobstructive coronary plaque disease was identified in one patient. Two patients had pericardial effusions.
Conclusions: Cardiac symptoms after ASO implant deserve thorough investigation. MSCT is feasible in the assessment of such patients and offers a unique assessment of the device to surrounding anatomic structures and should be considered as a useful adjunct to echocardiography in symptomatic patients. 相似文献
Objective: The purpose of this study was to determine the feasibility of MSCT in providing anatomic information in patients with persistent or recurrent symptoms after transcatheter closure of ASDs with ASO devices.
Methods: A retrospective analysis of adult patients who underwent ASO device implantation with subsequent MSCT imaging as a result of symptoms from June 2006 to May 2007 was performed. Data analysis included age, gender, size of ASO device, relationship of the device to surrounding structures, symptoms, and the length of time between device implantation and onset of symptoms.
Results: Eleven patients were identified with a mean age of 41 years. Patients presented with symptoms 1 week to 2.4 years after implantation. ASO size ranged from 8 to 36 mm. MSCT provided detailed information in all 11 cases regarding anatomic location of the device with respect to surrounding structures. Nonobstructive coronary plaque disease was identified in one patient. Two patients had pericardial effusions.
Conclusions: Cardiac symptoms after ASO implant deserve thorough investigation. MSCT is feasible in the assessment of such patients and offers a unique assessment of the device to surrounding anatomic structures and should be considered as a useful adjunct to echocardiography in symptomatic patients. 相似文献
60.
WILLIAM K. COWAN PETER KELLY ALI SAWAN WILLIAM J. CUNLIFFE LINDA HENRY MICHAEL J. HIGGS LINSLEY G. LUNT JAMES R. YOUNG CHARLES H. W. HORNE BRIAN ANGUS 《The Journal of pathology》1997,182(1):29-35
Traditional and immunohistochemical markers of prognosis were examined in 455 mammary carcinomas derived from breast cancer screening and compared with those of 277 carcinomas presenting symptomatically over the same period. Tumours detected by population screening under the U.K. National Health Service Programme do not differ from those detected by other screening projects, but compared with symptomatic cancers, screen-detected cancers are more likely to be in situ and if invasive, to be smaller, of lower grade, and to have invaded vessels, perineural spaces, and lymph nodes less frequently. Tubular and cribriform types are more often represented in screened patients. Immunohistochemical markers which have been proposed as being related to likely tumour behaviour (epidermal growth factor receptor, c-erbB-2 protein, oestrogen and progesterone receptors, cathepsin D, p53, and retinoblastoma protein) do not distinguish screen-detected from ‘clinical’ cancers. It is concluded that cancers diagnosed at screening do not differ biologically from those presenting clinically, but are the same lesions detected at an earlier stage of their natural history. © 1997 John Wiley & Sons, Ltd. 相似文献