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61.
The epidemiological studies suggest that aflatoxins, the toxic metabolites of the ubiquitous mold Aspergillus flavus, may play a significant role in the evolution of hepatocellular carcinoma in man in certain geographic areas of the world. To ascertain their carcinogenicity in nonhuman primates, we have administered highly purified aflatoxin B1, intermittently in the diet at 2 ppm, to 10 female and 8 male tree shrews. The tree shrew (Tupaia glis) is a nonhuman primate occurring throughout Southeast Asia which can be reared easily in captivity. Of 12 animals that survived, 6 of 6 female (100%) and 3 of 6 male (50%) tree shrews developed hepatocellular carcinomas between 74 and 172 weeks after the beginning of the experiment. None of the 8 control animals developed liver cancers. The estimated total amount of aflatoxin B1 consumed by these animals ranged from 24 to 66 mg. The development of liver tumors did not follow a specific pattern; considerable variation in hepatocellular responses to aflatoxin B1 was noted in these animals. In 2 tree shrews, the liver tumors were associated with severe post necrotic scarring; in the other 7 tumor-bearing livers, only mild to moderate portal fibrosis was encountered. This individual variation in hepatocellular response and in the amount of aflatoxin B1 required to induce hepatocellular carcinomas is attributed to inherent differences in the susceptibility within a given species of outbred animals and suggests extreme caution in proposing the "permissible" or "safe" levels of contamination of carcinogens in the food-stuffs.  相似文献   
62.
Reddy AT  Hedlund GL  Percy AK 《Neurology》2000,54(5):1175-1178
OBJECTIVE: To evaluate a series of patients with enlarged parietal foramina for associated brain anomalies. BACKGROUND: Enlarged parietal foramina are usually considered a benign calvarial defect. Methods: Ten patients with enlarged parietal foramina were identified. Seven patients were evaluated with neuroimaging: two by cranial CT and five by CT and/or MRI. Three patients who underwent MRI also underwent MR angiography or MR venography. RESULTS: Six of seven patients had cranial imaging showing a persistent falcine venous sinus. Three of six patients had variations of occipital cortical infolding. One patient had focal encephalomalacia in close proximity to the persistent falcine venous sinus and one had a previously undiagnosed atretic occipital encephalocele. CONCLUSION: This constellation of findings suggests that aberrant vascular evolution during fetal development may affect cerebrovascular, brain, or skull development. Individuals with enlarged parietal foramina (>5 mm) warrant imaging of underlying brain parenchyma and vasculature.  相似文献   
63.
We describ a case iaryngcul melanosis in a 62 year old male. the pigmentation was visible on gross examination during laryngoscopy ana histologicatly a single foci showing changes of carcinoma in situ was identified. The biopsy tissue, however did not reveal any frank changes of malignancy.  相似文献   
64.
The pectoralis major myocutaneous flap (PMMC flap) represents a landmark in the development of head and neck reconstructive surgery. After Stephan Ariyan first described its use for head and neck reconstruction in 1979, it has become tremendously popular and has revolutionised head and neck cancer surgery. Here, we present our initial experience with fourteen PMMC flaps in head and neck reconstruction. In most of the instances it was used for oral or oropharyngeal reconstruction. It was used for five other reconstructive tasks as well. Wound infection was the most common complication. There was no case of total flap loss. It has proven to be a reliable method of reconstuction in the head and neck.  相似文献   
65.
Breakthrough pain is a well recognized but ill-defined phenomenon that occurs commonly in the presence of otherwise stable, persistent pain. It is defined now as a "transient pain episode that occurs, or breaks through from the otherwise stable background pain." Breakthrough pain is usually associated with moderate to severe pain and may form a predictor of poor response to treatment with routine pharmacotherapy. Breakthrough pain is also associated with functional impairment and psychological distress. The assessment and treatment should be multidimensional. Although primary therapies such as chemotherapy, radiation treatment, and surgical options are explored, the mainstay of treatment is pharmacotherapy. Nonpharmacologic methods, such as orthotic devices and joint stabilizations along with behavioral methods, should be explored. Anesthetic and neurosurgical procedures are performed on a limited number of patients based on the prognosis, intractable nature of pain, and favorable risk/benefit ratio. Newer oral transmucosal fentanyl offers a favorable pharmacokinetic and pharmacodynamic profile and ease of administration.  相似文献   
66.
Previous studies in schizophrenia have shown alterations in membrane phospholipids and polyunsaturated fatty acids. However, these studies have primarily examined peripheral (non-neuronal) cell types. The purpose of the present study was to examine whether the membrane deficits seen in peripheral tissues are also observed in the brain. The caudate was the primary region of interest for this study. Using high-pressure liquid chromatography in conjunction with an evaporative light-scattering detector, we first measured the level of various membrane phospholipids (PL) in schizophrenic (n=11) and control groups with (n=7) and without (n=14) other mental disorders. Polyunsaturated fatty acids (PUFAs) were then determined by capillary gas chromatography. Within groups, there are no significant correlations between membrane PL levels and other collection and demographic parameters including age, postmortem interval, storage time and brain weight. Significantly lower amounts of phosphatidylcholine and phosphatidylethanolamine were found in postmortem brain tissue from schizophrenic patients than in those from control groups, even after accounting for potential confounds. In addition, strong reductions of total PUFAs and saturated fatty acids were found in schizophrenic brains, relative to control brains. Specifically, the reduced PUFAs were largely attributable to decreases in arachidonic acid (AA) and, to a lesser extent, its precursors, linoleic and eicosadienoic acids. There are no significant differences between the control groups with and without other mental disorders. The present findings suggest that deficits identified in peripheral membranes may also be present in the brain from schizophrenic patients. Such a deficit in membrane AA may contribute to the many biological, physiological, and clinical phenomena observed in schizophrenia.  相似文献   
67.
BACKGROUND: Systemic to pulmonary arterial collaterals often develop after bidirectional cavopulmonary anastomosis (BCPA). It has been proposed that such collaterals may be related to perioperative outcome and duration of effusions after the modified Fontan procedure. However, the incidence and significance of collaterals after BCPA remain uncertain. METHODS: To evaluate risk factors for, and significance of, such collaterals, we reviewed angiographic and clinical data for all 76 patients who underwent BCPA between January 1990 and June 1996 and had follow-up catheterization during or before 1997. RESULTS: The median age at BCPA was 10 months, and the median duration from BCPA to follow-up catheterization was 18 months. Arterial collaterals were detected on follow-up catheterization in 45 patients (59%). Factors associated with collateral development included a prior right-sided systemic-to-pulmonary arterial shunt, lower pre-BCPA end-diastolic ventricular pressure and pulmonary vascular resistance, and use and duration of cardiopulmonary bypass during the BCPA operation. Fourteen of the 45 patients (30%) underwent coil embolization of the collaterals. Forty-three patients have undergone extracardiac conduit Fontan, with 1 early and 1 late death. Collaterals were present in 22 of these patients, 7 of whom underwent pre-Fontan embolization. The duration from BCPA to Fontan was longer in patients with collaterals, but these patients were not more likely to have prolonged effusions than those without, and the duration of tube thoracostomy was significantly shorter in patients with collaterals. Embolization of collaterals did not affect the duration of effusions. CONCLUSIONS: Systemic-to-pulmonary arterial collaterals are common after BCPA. In contrast to prior reports, collaterals were not associated with a higher incidence of prolonged effusions after the Fontan procedure in our experience, and did not correlate with poor outcome.  相似文献   
68.
Determination of obstructive site in obstructive sleep apnoea (OSA) is of paramount importance is planning the management. Cephalometric evaluation of lateral X-rays when combined with clinical assessment and fibreoptic examination of the airway helps in locating the site of obstruction. The usual technique of cephalometry has been modified so as to give a better delineation of the soft tissues. Holding a 2mm card board in the mouth and using barium paste helped in more accurate calculations. Using our technique, various parameters have been quantified and a number of controls were studied and normal range derived. Further improvement in cephalometry has been done by using C.T. cephlometry topogram technique. A topogram is a scan done on a running table top cranio-caudally. Using the topogram technique 38 OSA patients were evaluated for all the parameters. The technique, its advantages over traditional cephalometry and the values obtained in the study are discussed in this paper.  相似文献   
69.
Two cases of spontaneous cessation of cerebrospinal fluid (CSF) rhinorrhea following iohexol computerized tomographic (CT) cisternography are presented. This report contradicts the current thinking about conservative treatment in CSF rhinorrhea. We propose that iohexol CT cisternography may have a therapeutic role in the management of spontaneous CSF rhinorrhea.  相似文献   
70.
Statins are a class of lipid-lowering medications used worldwide by millions of people and are safe for frequent use in most patients. However, they cause necrotizing autoimmune myopathy in some patients. We reviewed case reports of 80 patients from 2010 to present diagnosed with statin-induced necrotizing autoimmune myopathy (SINAM), aiming to analyze the clinical, physiological, serologic characteristics and outcomes of SINAM. The mean age of these patients was 66 ±9.4, the majority being male (61.3%). All patients reported proximal muscle weakness, and a few had myalgias, extra muscular symptoms such as dysphagia, and pulmonary complications. Most of the patients were on atorvastatin, simvastatin, or rosuvastatin. The mean creatine kinase was 10,094.2 ±7,351.7 U/l, and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase enzyme was positive for 93.8% of patients. The majority of patients were started on steroids; other treatments were also used. Prompt cessation of statins and initiation of immunosuppressants reduced morbidity and mortality.  相似文献   
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