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The management of a neck mass: presenting feature of an asymptomatic head and neck primary malignancy? 总被引:2,自引:1,他引:1
M Barakat L M Flood V H Oswal R W Ruckley 《Annals of the Royal College of Surgeons of England》1987,69(4):181-184
Malignancy of the upper aerodigestive tract is not always associated with obvious localizing symptoms. Presentation may then only be prompted by the appearance of a hard mass in the neck, a metastasis to a cervical lymph node. Neck exploration without a prior diligent search for an occult head and neck primary tumour is to be avoided as it compromises subsequent treatment. The diagnostic investigation of 112 patients complaining solely of a painless and enlarging neck swelling is reviewed. An otolaryngologic examination identified an asymptomatic malignancy of the head and neck in 72 patients (64%). Excision biopsy of the neck mass was required to achieve a diagnosis in only 29 (29%) of those patients who had not already undergone surgery. These results are presented to emphasize the need for a specialist examination of the head and neck prior to embarking on excision of any suspicious neck mass. 相似文献
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M A Gabal Y L Awad M B Morcos A M Barakat G Malik 《Veterinary and human toxicology》1986,28(3):207-212
Mycotoxicoses involving horses, rabbits and cattle have been studied. Fusarium tricinctum and T-2 toxin were isolated from all incriminated feedstuffs. Other isolated trichothecenes from the feed included HT-2, verrucarins and roridin. The toxins were separated, identified and quantitated using thin-layer chromatography, gas-liquid chromatography and mass spectrometry. T-2 toxin was detected in amounts varying from 0.5-204 ppm. The contaminated feedstuffs in connection with the affected horses and rabbits, included cereal grains (corn, cornstalks, bran and barley), whereas fescue hay was associated with the mucocutaneous findings in the bovine episode. The effects of the toxin(s) seemed to be host specific and varied according to the different animal species. Horses and rabbits developed primarily central nervous disorders with conspicuous pathological findings in the brain. Hepatitis and nephritis were also seen in naturally intoxicated horses and experimentally fed rats. Affected cattle developed mucocutaneous eruptions around the mouth and nostrils. In addition, dermonecrotic findings were observed involving the extremities, ear and tail. Fusariotoxicoses are toxic conditions of farm animals and man caused by the ingestion of cereal grains and forages contaminated by different fungal species of the genus Fusarium. A variety of clinical and pathological findings have been reported (5,6,10,13,15,17,31). This study concerns neuropathic findings in horses and rabbits and mucocutaneous lesions in cattle in association with T-2 toxin contamination. 相似文献
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We provide microscopic evidence that motile rod-shaped forms of Ramlibacter tataouinensis TTB310 are formed from dividing cyst-like cells. Careful estimation of the size of the two morphotypes was conducted using optical and transmission electron microscopy (TEM). The cyst-like cell was shown to be a sphere with a diameter Dc=850 nm. The rod-shaped form was a round-ended cylinder with length Lr=2.91 microm and diameter Dr=239 nm. The membrane area of the two morphotypes was the same. However, the formation of rods from cysts involved loss of two-thirds of the cell volume. TEM showed that, prior to division and transition into rods, cysts contained condensed cytoplasmic material. These results suggest that the morphological transition occurs by pure reshaping of cells. 相似文献
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Tibor Hortobágyi Joseph A. Houmard Richard G. Israel John W. Carpenter Judy Heath Hisham A. Barakat 《European journal of applied physiology》1993,67(3):226-230
Summary The purpose of this study was to determine the effects of short-term exercise cessation on lipid and lipoprotein profile and insulin sensitivity in highly trained runners (n=12; mean age 19.9 years) and power athletes (n=12; mean age 24.4 years). Following 14 days of exercise cessation, running time to exhaustion and maximal oxygen uptake decreased by 9.2% and 4.8% (P < 0.05) in the runners, while in the power athletes one repetition maximum squat and bench press did not change (P>0.05). No changes occurred in body composition. Data from a 2-h oral glucose tolerance test revealed an impairment of the glycemic state in all athletes (P<0.05). In contrast, exercise cessation did not significantly (P>0.05) alter plasma levels of cholesterol, triglycerides, and low density (LDL) and high density lipoprotein (HDL). No changes were observed in HDL2, HDL2b, and HDL3 subfractions, LDL diameter, and qualitative LDL pattern (P>0.05). These data thus suggest that despite a decrease in insulin sensitivity, short-term exercise cessation, independent of exercise mode, was insufficient to alter plasma lipid and lipoprotein profiles in well-trained athletes. 相似文献
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BACKGROUND: To evaluate the efficacy of the peripheral leukocyte count and chest X-rays as an index which could be used in the early assessment of the severity of acute pancreatitis in an Emergency Room. METHODS: We prospectively evaluated the peripheral leukocyte count and the findings of chest X-rays in 181 consecutive patients (102 males, 79 females, mean age 61 years, range 16-97) who were admitted to our Emergency Department with acute pancreatitis. One hundred twenty six patients had mild pancreatitis and 55 had severe pancreatitis. The peripheral leukocyte count and the chest X-rays were evaluated in all patients upon admission. The Ranson criteria were also assessed. RESULTS: Using a cut off value of 13,000/mm3, 45% of the patients with severe pancreatitis and 17% of those with mild acute pancreatitis had a peripheral leukocyte count greater than 13,000/mm3. Pleural or pulmonary alterations observed on chest X-ray were found in 66% of patients with severe pancreatitis and in 2% of those with mild acute pancreatitis. A peripheral leukocyte count greater than 13,000/mm3 and/or pleural or pulmonary alterations present on chest X-ray were found in 78% of the patients with severe pancreatitis and in 19% of those with mild pancreatitis. The Ranson criteria greater than or equal to three were found in 45% of the patients with severe acute pancreatitis and in 16% of those with the mild form of the disease. The positive predictive value was 92% for the presence of alterations on the chest X-rays, 64% for the alteration of at least one of the abnormal findings on the chest X-ray and a peripheral leukocyte count greater than 13,000/mm3, 56% for a peripheral leukocyte count greater than 13,000/mm3, and 54% for the presence of Ranson criteria greater than or equal to three. The negative predictive values were similar. CONCLUSIONS: The presence of pleural or pulmonary alterations on chest X-rays may be useful in the Emergency Room for the early identification of patients with severe acute pancreatitis. 相似文献
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P Koczewski M Shadi M Napiontek W Marciniak 《Chirurgia narzadów ruchu i ortopedia polska》2000,65(3):277-286
The results of femoral lengthening using the Italian modification of the Ilizarov are presented. Mean age of the patients was 14 years (ranging from 7 to 29). The most frequent etiology of limb shortening was femoral hypoplasia (7 patients) and sequelae of septic arthritis of the hip and/or the knee (6 patients). Indications for surgical treatment were limb shortening from 3 to 12 cm (mean 6.5 cm), along with axial deviation ranging from 10 degrees to 40 degrees in 6 patients. Mean follow-up time was 15 months (ranging from 6 to 35 months). The Ilizarov apparatus was based on two distal rings, stabilized by "K" wires, and proximally by a ring connected with an Italian femoral arch, stabilized by a Schanz screw. Planned lengthening (ranging from 3.5 cm to 12 cm) was achieved in all treated patients. The healing index ranged from 0.8 to 2.1 month/cm (mean 1.4). Problems, obstacles and complications were analyzed according to the Paley classification. In all 16 patients without primary knee stabilization, limited knee flexion ranging from 5 degrees to 90 degrees (mean 40 degrees) was noted during the distraction phase, which didn't improve significantly during the consolidation phase. Knee flexion improved to a mean 90 degrees after a 6 month follow-up. Bone regenerate defects (cysts, narrowing) were noted in 4 patients. Secondary knee stabilization was performed in 2 cases. In the first case because of knee pain and a severe limitation of knee motion. In the second, during a revision procedure because of distal femur angulation. Premature consolidation was noted in one patient and was treated by osteotomy. In one case axial deviation during the consolidation phase required osteotomy. In another case a fracture of the femur was treated by a plaster cast. In one case 1.5 years after the lengthening procedure subluxation of the hip was noted. Permanent knee flexion limitation to less than 90 degrees was noted in 6 patients. Femoral lengthening with the use of the Italian modification of the Ilizarov device give a high incidence of knee range of motion limitation, which can be decreased by preserving more than 30 degrees knee flexion during the distraction phase. 相似文献