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31.
We report a case of seminoma associated with crossed fused renal ectopia and a duplicated vena cava. The impact of these congenital anomalies on the treatment of testicular seminoma is discussed.  相似文献   
32.
We have previously demonstrated that in pentylenetetrazole (PTZ)-kindled rats, cysteamine causes prolonged depression of the kindled state. We now report that administration of cysteamine before or during the kindling process prevents attainment of the kindled state. This effect lasts long after cysteamine administration has ceased, suggesting that depletion or somatostatin may not be the only mechanism underlying cysteamine's effect on kindling. The results also support the likelihood that PTZ kindling primarily effects neocortical rather than limbic structures.  相似文献   
33.
A desmopressin-induced ACTH increase has been recently suggested to be specific for pituitary-dependent Cushing's disease. We present the case of a 47-year-old woman with Cushing's syndrome due to ectopic ACTH production by a bronchial carcinoid. While CRH failed to induce an ACTH or cortisol response, intravenous administration of desmopressin led to a 47% increase in serum ACTH and a 42% increase in serum cortisol concentration. After surgical removal of the tumour, the desmopressin response became negative. In vitro , ACTH production by tumour cells obtained at surgery was also stimulated by desmopressin but not by CRH. Additional receptor mRNA expression studies using RT-PCR revealed expression of both V2 and V3 vasopressin receptor subtypes in the carcinoid tumour at a level comparable to that recently described in pituitary corticotroph adenomas. This case illustrates that ACTH stimulation by desmopressin is not specific for pituitary-dependent Cushing's syndrome as vasopressin receptor subtypes known to interact with desmopressin may also be found in ectopic tumours producing ACTH.  相似文献   
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The purpose of this study was to assess the feasibility of imaging of bladder cancer with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scanning. We studied 12 patients with histologically proven bladder cancer who had undergone surgical procedures and/or radiotherapy. Retrograde irrigation of the urinary bladder with 1000–3710 ml saline was performed during nine of the studies. Dynamic and static PET images were obtained, and standardized uptake value images were reconstructed. FDG-PET scanning was true-positive in eight patients (66.7%), but false-negative in four (33.3%). Of 20 organs with tumor mass lesions confirmed pathologically or clinically, 16 (80%) were detected by FDG-PET scanning. FDG-PET scanning detected all of 17 distant metastatic lesions and two of three proven regional lymph node metastases. FDG-PET was also capable of differentiating viable recurrent bladder cancer from radiation-induced alterations in two patients. In conclusion, these preliminary data indicate the feasibility of FDG-PET imaging in patients with bladder cancer, although a major remaining pitfall is intense FDG accumulation in the urine. Present address: Department of Radiology, National Defense Medical College, 3-2 Namiki, Tokorozawa 359, Japan  相似文献   
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Opioids and stress in man   总被引:1,自引:0,他引:1  
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Intravesical administration of bacillus Calmette-Guerin has been shown to be highly effective treatment of superficial bladder cancer. Complications from bacillus Calmette-Guerin therapy are usually minor but serious and even fatal reactions can occur. Five recent cases illustrate the gravity of bacillus Calmette-Guerin sepsis. One man with severe debility and the organic brain syndrome died acutely with a fever of 40 C. Two men had frank sepsis that progressed to multiorgan failure and death. Sepsis progressed despite the use of isoniazid, rifampin and streptomycin. Two men who had equally progressive sepsis with intravesical bacillus Calmette-Guerin survived with the use of cycloserine for the first 72 hours of treatment. Triple antituberculous antibiotics, including cycloserine, may be lifesaving. Sepsis resulted from intravenous absorption through inflamed or disrupted urothelium. Bacillus Calmette-Guerin treatment should not be administered in the presence of severe cystitis or after grossly traumatic catheterization.  相似文献   
39.
Improving the management of bladder cancer with fluorescence cystoscopy.   总被引:1,自引:0,他引:1  
Endoscopic visualization (cystoscopy) and transurethral resection are effective, well-tolerated diagnostic and treatment techniques for bladder cancer. However, it is widely recognized that cystoscopy can miss biologically important lesions, such as carcinoma in situ. Attempts to improve the effectiveness of cystoscopy are not new, but initial methods were impractical and had limited efficacy. Fluorescence cystoscopy became feasible with the discovery that intravesical administration of aminolevulinic acid (ALA) made bladder cancers fluoresce when exposed to blue light. More recently, the creation of a hexyl ester of ALA (HAL) made this technique practical, because HAL significantly shortens the amount of time needed for drug exposure prior to cystoscopy. Not surprisingly, studies have shown that fluorescence cystoscopy can reveal carcinoma in situ that is visually occult under conventional (white-light) cystoscopy. An unexpected finding was that fluorescence cystoscopy also enhanced the detection of papillary tumors. Studies with ALA have shown that resection of bladder cancer with fluorescence results in improved disease-free survival compared to conventional resection under white light. This report summarizes some of the recent studies of fluorescence cystoscopy in bladder cancer.  相似文献   
40.
The extrusion-capture model for chromosome partitioning in bacteria   总被引:21,自引:0,他引:21       下载免费PDF全文
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