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91.
Anabolic androgenic steroids (AAS) are misused by athletes to improve their physical performance. AAS with similar groups and configuration indicate that testosterone is the base of this ability to stimulate anabolic activity. The effect of these compounds on the breast tissue of males that consume them is a confirmation of its metabolic pathway. To confirm its hormonal effects, the status of estradiol and progesterone receptors (ER, PgR) status was determined in cytoplasmic and nuclear fractions (HRc, HRn) of 8 premalignant breast tissues from 8 bodybuilders (aged 21 to 45 years) under AAS stimulation. The control group included 5 males with benign disorders of the breast, but not due to AAS administration. The concentrations of ERc and ERn were significantly higher (p < .05) in males under AAS stimulation than in males without these. The concentrations of PgRc and PgRn do not differ between these two groups (p > .05) The benign breast disease is remarkably similar in female and male patients, suggesting a common origin. In the same way, the measurement of both HRc and HRn is necessary to accurately report receptor concentration.  相似文献   
92.
Inflammatory abdominal aortic aneurysms are known to be associated with retroperitoneal fibrosis and ureteral complications. We report a case of an inflammatory aneurysm that produced bilateral ureteral envelopment and obstructive renal failure. Incidence, pathogenesis and clinical onset of this kind of aneurysms and management of the ureteral complications are reviewed.  相似文献   
93.
BACKGROUND: The inflammatory response has been widely investigated in patients with acute respiratory distress syndrome (ARDS) and pneumonia. Studies investigating the diagnostic values of serum cytokine levels have yielded conflicting results and only little information is available for the differential diagnosis between ARDS and pneumonia. METHODS: Clinical and physiological data, serum concentrations of tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6, and quantitative cultures of lower respiratory tract specimens were obtained from 46 patients with ARDS and 20 with severe pneumonia within 24 hours of the onset of the disease and from 10 control subjects with no inflammatory lung disease. Cytokine concentrations were compared between groups and determinants in addition to the diagnosis were tested. RESULTS: Serum TNF-alpha levels were significantly higher in ARDS patients (67 (57) pg/ml) than in patients with severe pneumonia (35 (20) pg/ml; p = 0.031) or controls (17 (8) pg/ml; p = 0.007). For IL-1beta and IL-6 the observed differences were not statistically significant between patients with ARDS (IL-1beta: 34 (65) pg/ml; IL-6: 712 (1058) pg/ml), those with severe pneumonia (IL-1beta: 3 (4) pg/ml, p = 0.071; IL-6: 834 (1165) pg/ml, p = 1.0), and controls (IL-1beta: 6 (11) pg/ml, p = 0.359; IL-6: 94 (110) pg/ml, p = 0.262). TNF-alpha (standardised coefficient beta = 0.410, p<0.001) and IL-1beta (standardised coefficient beta = 0.311, p = 0.006) were most strongly associated with the degree of lung injury, even when the diagnostic group was included in the statistical model. CONCLUSIONS: Serum TNF-alpha levels were higher in patients with ARDS than in those with severe pneumonia or in control subjects. Multivariate results suggest that the levels of systemic TNF-alpha and IL-1beta reflect the severity of the lung injury rather than the diagnosis.  相似文献   
94.
Hibernoma is a rare benign tumor arising in brown fat arising in young adults with similar incidence in both sexes. They are generally subcutaneous reaching in some instances a considerable size. The interscapular region, shoulders, head and neck are the main locations, but rare cases have been described in a wide variety of sites. Histologically three types of cells mixed in different proportions corresponding to the stages of maduration of the fatty cells. They are benign tumors with not recurrence after excision. We report a pleural hibernoma, a location not reported previously in the literature.  相似文献   
95.
PURPOSE: To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built. PATIENTS AND METHODS: Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response. RESULTS: The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity. CONCLUSION: h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms.  相似文献   
96.
Advanced stage ovarian cancer has a high rate of recurrence even after surgery followed by chemotherapy combining carboplatin and a taxane. New strategies are currently under way to combat this situation and one of the most promising ones is based on the knowledge that angiogenesis, the mechanism of formation of new blood vessels coupled with the degradation of the extracellular matrix for metalloproteinases, could be crucial in the development of this tumor. The principal molecule implicated in angiogenesis process of ovarian cancer is the vascular endothelial growth factor (VEGF). Several studies are now in progress to clarify its role as a diagnostic tool or its therapeutic implication. Presently, there is no indication for the use of VEGF in a preliminary diagnosis seeing that an increase in levels can be seen in both benign and malignant ovarian conditions. VEGF is also responsible for an increase in vascular permeability and is directly related to symptoms such as ascites and pleural effusion, both of which are frequent in ovarian cancer. Several papers have analised the role of VEGF as a prognostic factor and some of them do confirm VEGF as an independent prognostic factor in ovarian cancer. VEGF and the metalloproteinase system coupled with angiogenesis are currently being evaluated as therapeutic targets but no positive results have yet to be seen in this field.   相似文献   
97.
BACKGROUND AND PURPOSE: Modern conformal radiotherapy treatments require accurate dose calculation in any relevant clinical situation. One of these situations is the treatment of lung tumors, where irradiation has to be planned under challenging conditions for dose calculation. In this study we assess the errors in dose values predicted by fast Fourier transform convolution (FFTC) and multigrid superposition (MGS) algorithms implemented in a commercial treatment planning system (TPS). MATERIALS AND METHODS: FFTC and MGS algorithms were used in a FOCUS 3.0.0 (Computerized Medical Systems, USA) to calculate doses in treatment plans using photon beams of 6 and 25 MV nominal energy from a Saturne 43 linac (GE Medical Systems, USA). A 10x10-cm beam irradiating a mediastinum-lung and a thoracic wall-lung-thoracic wall modeled geometry was assessed. The calculated data were compared with measurements performed with radiographic films and ionization chamber. RESULTS: FFTC algorithm leads to an average deviation from ionometric dose measurements of over 10%. Discrepancies between measured and calculated beam fringe values (distance between 50 and 90% isodose lines) of up to 8 mm were observed. For MGS algorithm, all the points assessed in both geometries fulfilled the 3%-3 mm accuracy criteria and the average deviation of absolute dose was about 1%. A maximum of 3 mm deviation in the beam fringe for any depth was found and was within 2 mm beyond the buildup region. Deviations between ionometric and film measurements were within 3%. CONCLUSIONS: MGS algorithm assesses with reasonable accuracy dose distributions and absolute dose in inhomogeneous regions like the lung region. Therefore, and respecting the inhomogeneity dose calculation, the system could be used in routine clinical practice and in dose-escalation programs. This is not true in the case of FFTC algorithm which leads to errors greater than 10% in the absolute dose calculation and underestimates the beam fringe by up to 8 mm.  相似文献   
98.
99.
A 15 year old boy with autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy syndrome suffered recurrent episodes of severe intractable diarrhoea, steatorrhoea, and hypocalcaemia. The only treatment modality, which controlled the malabsorption syndrome, was immunosuppression with intravenous high dose methylprednisolone and oral methotrexate maintenance therapy.  相似文献   
100.
A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
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