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Conclusions  MPI has weathered many challenges over the decades, and, with advances such as gated SPECT acquisition, technetium radiotracers, and attenuation correction software, it has overcome many of its shortcomings to remain a cornerstone of noninvasive cardiac imaging, which has high diagnostic accuracy in women.14  相似文献   
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U Chikte  S Naidoo 《SADJ》2000,55(12):661-662
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Twenty-four hour urinary free cortisol and mean and integrated 13h00-16h00 plasma cortisol levels were measured in 9 patients with proven Cushing's syndrome (5 with Cushing's disease, 2 with ectopic adrenocorticotrophic hormone production due to bronchial carcinoma and 2 with adrenal adenomas) and in 21 patients without Cushing's syndrome. The 24-hour urinary free cortisol levels and mean and integrated 13h00-16h00 plasma cortisol estimations clearly distinguished patients with Cushing's syndrome from those without. However, adequate suppression on dexamethasone suppression tests (false negatives) were obtained in 3 of the 9 patients with Cushing's syndrome. Since the integrated 13h00-16h00 plasma cortisol estimation is cheaper and simpler than the mean 13h00-16h00 plasma cortisol estimation, we recommend it as an adjunct in the diagnosis of Cushing's syndrome.  相似文献   
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A fatal case of strychnine intoxication is reported. The patient expired despite early aggressive management and prevention of metabolic complications. Serial blood levels are reported. In contrast to a previous report describing first order elimination kinetics, our data suggest that strychnine follows Michaelis-Menton elimination kinetics. The case illustrates the rapid, dramatic course of severe strychnine ingestions. A review of the toxicokinetics, mechanism of action and treatment of strychnine intoxication follows.  相似文献   
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Two types of fluid regimen were provided for patients having labour induced under epidural analgesia. Reasons for the infusion were to pre-load the circulation before the epidural, and subsequently to sustain maternal hydration. Both fluids were isotonic, one was predominantly saline based (Hartmann's solution) and the other contained both saline and dextrose. Blood glucose and serum sodium, lactate and beta-hydroxybutyrate were measured before the start of induction, at delivery and in the cord sample. Blood glucose and serum sodium were measured in the babies at 12 and 24 h of age. The dextrose-saline fluid caused small but significant changes in blood glucose and serum sodium which did not exceed the normal reference limits for either. The use of Hartmann's solution was associated with considerable rises in maternal serum beta-hydroxybutyrate at delivery. Neither fluid had any significant effect on the blood glucose or serum sodium in infants at 12 and 24 h of age.  相似文献   
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Liver transplantation for severe Amanita phalloides mushroom poisoning   总被引:1,自引:0,他引:1  
Amanita phalloides mushroom poisoning is an increasingly common and potentially lethal problem for which liver transplantation offers definitive therapy in selected patients. When significant liver dysfunction appears, early transfer to a liver transplant center is important to identify appropriate candidates and to begin the search for a donor organ. The clinical course of five severely poisoned patients, four of whom underwent liver transplantation, is reviewed. Indications for transplantation included primarily a markedly prolonged prothrombin time that was only partially correctable and a constellation of findings including metabolic acidosis, hypoglycemia, hypofibrinogenemia, and increased serum ammonia, following a marked elevation in serum aminotransferase levels. Unlike viral fulminant hepatic failure, grade III or IV hepatic encephalopathy, marked elevation of the serum bilirubin level, and azotemia were not indications for transplantation. Resected livers demonstrated hepatocyte viability of 0% to 30%. Manifestations of Amanita poisoning complicating preoperative and/or postoperative care included severe diarrhea, gastrointestinal hemorrhage, hypophosphatemia, bowel edema, and marrow suppression with lymphopenia, thrombocytopenia, and neutropenia. All five patients are well 1 year later. This largest experience with liver transplantation for Amanita poisoning further defines the early clinical and laboratory indications for, and the unique complicating features of, transplantation in this setting.  相似文献   
9.
S Naidoo  U M Chikte 《SADJ》2000,55(12):683-686
Cancrum oris (noma) is a gangrenous infection that develops in the mouth and spreads rapidly to other parts of the face. The disease occurs mostly in conditions of poverty, poor hygiene and malnutrition. In sub-Saharan Africa the frequency in several countries is estimated to be 1-7 cases per 1,000 population, and as many as 12 cases per 1,000 in the most affected communities. About 90% of these children die without receiving any care, yet the disease can, and should, be prevented. With increasing numbers of children who are malnourished and who have compromised immune systems (compounded by the HIV pandemic) the prevalence of conditions such as noma is likely to increase. Among the earliest features of noma are excessive salivation, marked fetor oris, facial oedema and a greyish-black discolouration of the skin in the affected area. This devastating gangrenous lesion may involve the cheek, the chin, the infra-orbital margin, palate, nose, antrum and virtually any part of the face. This report describes a 4-year-old HIV-positive African girl, who was abandoned, discharged from the Plastics Unit and now lives in a child care sanctuary. Little is known about her history prior to her arrival at the home a few weeks previously. The clinical examination revealed a delay in growth and physical development equivalent to that of a 2-year-old child. The left cheek had a perforating ulcer in a healing phase. The perforation, about 1 cm in diameter, was surrounded by oedematous tissues showing a mild to moderate erythema. The peripheral oedema extended to the lower palpebral, the upper labial, left labial commissural, mandibular and pre-parotid regions. Submental, submandibular and cervical lymph nodes were mildly painful upon palpation. The child was not pyretic. The intra-oral examination revealed the features of acute necrotising gingivitis (ANG). ANG was generalised and showed classic interdental crater-like ulcers covered with whitish debris. Halitosis was pronounced. Examination of the second quadrant revealed a large ulcer extending from the distal aspect of the deciduous canine to the distal aspect of the second deciduous molar. The adjacent palatal mucosa was severely oedematous. The alveolar bone supporting the first and the second molars was completely exposed to the fundus of the vestibulum. It was not possible to obtain intraoral photographs or radiographs. Chlorhexidine gluconate (0.2% solution) and metronidazole tablets, 200 mg twice daily for 15 days were prescribed. The child was seen every alternate day for 10 days and her condition improved rapidly. Halitosis had subsided. She was then referred to the Johannesburg Hospital for further treatment under general anaesthesia. The proposed treatment plan was as follows: removal of dental accretions and polishing of all teeth, extraction of the left maxillary teeth supported by non-vital bone, resection of the necrotic bone in the left maxilla and reconstructive surgery in the left cheek.  相似文献   
10.
Cervical cancer is the most common gynecologic malignancy of the developing world. The oncogenic role of human papilloma virus (HPV) is well known. Attention is now focusing on the complicit genetic changes, which allow progression of these tumors. Regarding these changes, deletion of tumor suppressor genes (loss of heterozygosity [LOH]) is the preferred pathway of progression with only a subset manifesting microsatellite instability (MSI). Implicated loci include 3p14.1-22. Several studies suggest that the mutator phenotype in cervical cancer may correlate with higher grade tumors, more advanced disease stage, and poor outcome. Unlike colorectal cancer, in which an inverse relationship has been demonstrated between microsatellite instability and loss of heterozygosity, cervical cancers expressing MSI have been found to coexpress LOH at other loci. In this study we analyzed 8-microsatellite loci including p53, DCC, APC, the MMR gene hMLH1 and 2 regions of interest on chromosome 3 in a high-risk population group in which HPV infection is endemic.  相似文献   
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