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991.
During a 26-year period (1961-1987), a total of 18 patients with primary non-Hodgkin's lymphoma (NHL) of the paranasal sinuses and nasal cavity received radiation therapy at (University of California at Los Angeles) UCLA Medical Center. At the time of diagnosis and using the available diagnostic methods, none of these patients had clinically detectable disease beyond the paranasal sinuses. All 18 patients were staged IE by the Ann-Arbor system. When the patients were staged according to the AJC staging system from epithelial tumors, half presented with advanced T3-4 disease. Diffuse histiocytic lymphoma was the most common histology (eight cases) and maxillary sinus, the most common site of origin (11 cases). All nine T1-2 tumors received radiation therapy alone, while radiation and chemotherapy was used in seven of nine advanced T3-4 staged tumors. The mean follow-up was 71 months. At last follow-up, eight of nine T1-2 patients were rendered disease-free. In contrast, only four of nine T3-4 patients had long-term disease-free survival. Seventy-five percent of the failure occurred within 2 years. Radiation therapy alone achieves high local control in small tumors (T1-2), while large tumors (T3-4) require aggressive combined treatment, i.e., radiation and chemotherapy.  相似文献   
992.
The thermic effect of a meal (TEM) was measured in a group of 10 prepubertal obese children before (OB) and after (OA) weight reduction, and in a group of 10 age-matched control children (C) of normal body weight. Following a hypocaloric balanced diet for 6 +/- 1 months, the obese children lost 5.2 +/- 1.3 kg i.e. 11% of their initial body weight. The thermic response to the mixed liquid meal - fed at an energy level corresponding to 30% of the 24 h premeal resting metabolic rate - was found to be significantly lower in OB than in C children (61 +/- 25 kJ.3h-1 vs 79 +/- 21 kJ.3h-1, P less than 0.05), despite their higher test meal energy. After slimming, the TEM of obese children increased towards the controls' values (73 +/- 30 kJ.3h-1). These results support the hypothesis of the existence of a moderate thermogenic defect in some obese children which represents a consequence rather than an aetiological factor of obesity.  相似文献   
993.
Psychophysical functions are used to characterize both normal perception and altered perception among patients with neglect, yet the reliability of these functions is rarely examined. The present study examined two-week, test-retest reliability for power functions derived from line bisection data among 58 normal, young and old, male and female subjects. Power function exponents and constants were, at best, moderately reliable over time. The size of the exponent tended to decrease at retesting. Reliability coefficients varied by age and gender; they were highly significant for young men, marginally significant for older men, and non-significant for women. Race influenced reliability as coefficients were significant for Caucasian subjects but not for African American subjects. Age and gender effects in this study parallel those in the literature on pseudoneglect, and they may reflect hemispheric differences in visuo-spatial processing, magnitude estimation, or both.  相似文献   
994.
The reconstruction of large bone and joint defects after the resection of malignant tumors remains a major challenge. Chemotherapy has significantly lowered the risk of metastasic disease, but complications associated with reconstructive techniques continue to result in late morbidity. In the present study, biomechanical torsion testing, gait analysis, and histomorphometric and scanning electron microscopic evaluations of 24 dogs were used to examine the effects of preoperative and postoperative administration of cisplatin on the biologic fixation of a porous-coated segmental replacement prosthesis. The chemotherapy consisted of four cycles of cisplatin administered at a dosage of 75 mg/m:2 preoperatively or postoperatively. The healing was enhanced by use of an autogenous corticocancellous bone graft. The graft was placed evenly around the prosthesis and the adjacent femoral cortex. Mechanical analyses of torsional stiffness, yield strength, and maximum strength revealed no statistically significant differences between the groups at 12 weeks. Such lack of difference was mainly due to the penetration of highly organized fibrous tissue into the porous surface; this provided strong fixation of the implant to bone even in the absence of bone ingrowth. Although bone ingrowth into the prostheses was not affected, electron microscopic, histomorphometric, and radiologic analyses showed a clear difference in the formation of new bone around the prosthesis. Preoperative chemotherapy did not alter the formation of new bone, but specimens from animals treated postoperatively with cisplatin showed significantly less bone graft resorption and less new bone formation. Hence, the effect of cisplatin administration caused only a temporary delay, not a permanent effect, on extracortical capsule formation. The formation of extracortical bone and soft tissue might prevent debris-incised osteolysis and, therefore, prevent late complications by forming a tight capsule around the bone-prosthetic interface.  相似文献   
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997.
A case of Takayasu's disease in a 22-year-old woman who complained of severe fainting attacks is presented. Bilateral obstruction of the cervical arteries was confirmed by digital subtraction angiography. Preoperative technetium-99m hexamethylpropylene amine oxime brain SPET in the sitting position showed bilateral hypoactivity in the temporoparietal areas. Subtraction brain SPET showed slightly increased activity in the lying position. The patient has had no fainting attacks since bypass surgery. Postoperative 99mTc-HMPAO brain SPET in the sitting position showed normal activity except in the right temporoparietal area. This area was filled in the lying position. 99mTc-HMPAO brain SPET is the only technique that can visualize the cerebral blood flow in any position, this capability deriving on the fact that the distribution of 99mTc-HMPAO in the brain is fixed in the first 2-3 min following injection. The use of both sitting and lying 99mTc-HMPAO brain SPET is very useful for detecting an abnormality (i.e. an inhomogeneous response due to the fall in perfusion pressure) that could not be seen if the cerebral blood flow were to be assessed only in the lying position.  相似文献   
998.
Immunoscintigraphy with radiolabelled monoclonal antibodies is widely used to detect solid tumours, but only a few trials have been carried out concerning the specific in vivo localization of an inflammatory process. The purpose of this study was to investigate the detectability of tuberculous foci utilizing this method with radiolabelled bacillus Calmette-Guérin (BCG)-specific F(ab')2 in rabbits. All of the tuberculous lesions (n = 8) were clearly visualized on serial scintigraphy for up to 48 h after injection of the antibody. Immunohistochemical and Ziel-Neelson staining of the tuberculous lesions confirmed the presence of the tuberculous antigens and bacilli. It failed to demonstrate any sustained retention of the BCG-specific antibody fragment in the control group with syphilitic orchitis (n = 2). Therefore, the specific in vivo localization of tuberculosis is feasible by immunoscintigraphy.  相似文献   
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