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41.
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   
42.
目的 无水茶碱修筛缓释片——优喘平(portheo)治疗可逆性支气管阻塞患者(FEV_1<预计值80%)30例。观察其疗效及安全性,同时监测其STLD(血清浓度),并与氨茶碱片口服后STLD进行比较。结果显示;优喘平治疗哮喘及慢性阻塞性肺病疗效达90.6%,三例有轻微副作用。优喘平服用后4小时STLD即达有效浓度,8小时后STLD多维持在有效水平,峰值多<20ug/ml。氨茶碱0.1/次,3次/日,连服4天后STLD谷值多<5ug/ml,0.2/次,3次/日,连服4天后STLD谷值均>5ug/ml,峰值均>20ug/ml,且多有较重毒付作用。优喘平0.4/次,1次/日与氨茶碱0.1/次,3次/日比较,疗效好,而比氨茶碱0.2/次,3次/日,毒付反应少。优喘平与氨茶碱有显著差异。(P<0.01)。  相似文献   
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44.
This case report illustrates atypical magnetic resonance (MR) imaging findings in a liver hemangioma mimicking a malignant lesion—lower signal intensity than cerebrospinal fluid on T2-weighted spin-echo images and lack of early enhancement on dynamic contrast material—enhanced gradient-echo images. Pathologic analysis demonstrated nearly total replacement of the vascular cavities by dense fibrous tissue. In this rare, sclerosed form, this lesion could not be defined as a hemangioma with MR imaging.  相似文献   
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46.
PURPOSE: To study the diagnostic ability of scanning laser polarimetry with variable corneal compensation (GDx VCC) for early glaucomatous (EG) eyes and glaucoma-suspect (GS) eyes in a Taiwan Chinese population. METHODS: This prospective cross-sectional study included 82 EG eyes (mean deviation, MD: -3.32 +/- 2.20 dB), 45 GS eyes (MD: -2.43 +/- 2.16 dB), and 62 normal eyes. Retinal nerve fiber layer thickness of each subject was measured using GDx VCC and Humphrey Field Analyzer visual field testing. Measured GDx VCC parameters were compared among groups. The area under the receiver operating characteristic (AROC) curve of each parameter was used to differentiate normal from EG eyes or GS eyes. The correlation between MD and each parameter was also evaluated. RESULTS: For both normal versus EG and normal versus GS, the largest AROC values were for nerve fiber indicator, superior average thickness, and inferior average thickness. There was no significant correlation between MD and GDx-VCC-measured parameters either in EG or GS eyes. CONCLUSIONS: GDx VCC shows only moderate ability to distinguish normal eyes from eyes with early glaucoma. However, its diagnostic role in eyes with suspicious discs and normal visual fields is uncertain at this moment in the Taiwan Chinese population. Further studies are needed to address this issue.  相似文献   
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48.
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin.  相似文献   
49.
Summary: Severe secondary hyperparathyroidism in chronic dialysis patients has been recently treated by supraphysiological concentration of calcitriol achieved through pulse therapy. However, there are many patients resistant to this therapy, who usually have larger parathyroid gland(s). to overcome this resistance, calcitriol was injected directly into the enlarged glands under ultrasonographic guidance. We injected 70–90% of the calculated gland volume of calcitriol solution (1 μg/mL) into the glands of 7 patients three times per week for 2 weeks. the parathyroid hormone (PTH) levels decreased significantly after 2 weeks of direct injections of calcitriol. Following a further 4 weeks of calcitriol pulse therapy, PTH levels remained suppressed and serum alkaline phosphatase activity and the volume of parathyroid glands also decreased. During the long-term follow up, five patients remained well controlled with calcitriol pulse therapy, while two patients needed ethanol injections to control hyperparathyroidism. Although we could not completely rule out a toxic effect of the vehicle, direct injection of calcitriol into parathyroid glands may be another treatment option for chronic dialysis patients. Our data further support the important role of resistance of parathyroid cells to calcitriol in the pathogenesis of parathyroid hyper function in uraemic patients.  相似文献   
50.
Several authors have discussed an alteration of adrenergic receptivity in arterial hypertension. De Champlain (Hypertension 1990; 8: S77-S85) suggested that postsynaptic alpha 1-adrenergic functions became dominant while beta-adrenergic functions are attenuated in arterial hypertension. However, the status of presynaptic alpha 2-adrenoceptors remains unknown. The present study investigates presynaptic alpha 2-adrenoceptors in hypertension through the measurement of plasma levels of noradrenaline after administration of yohimbine, an alpha 2-adrenoceptor antagonist, in essential hypertension. Yohimbine (0.2 mg/kg per os) induced a 73% increase of plasma levels of noradrenaline in hypertensive patients (n = 12) and a 178% one in normotensive subjects (n = 6, p < 0.05). A similar significant difference was found in experimental neurogenic hypertension observed in awake dogs 3 weeks after sinoaortic denervation: the increase in plasma concentrations of noradrenaline after yohimbine (0.5 mg/kg i.v.) was +279% in hypertensive versus +642% in normotensive dogs (p < 0.05). The results show that the magnitude of the yohimbine-induced sympathetic activation is lower in hypertensives than in normotensives. They suggest the existence of a presynaptic alpha 2-adrenoceptor desensitization in arterial hypertension. The abnormality of this presynaptic inhibitory mechanism can increase the sympathetic tone and help to develop and maintain arterial hypertension.  相似文献   
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