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31.
The risk of recurrence and progression in 170 patients presenting with pTa urothelial tumours of the bladder has been estimated so that follow-up can be rationalised. Patients were followed up for between 1 and 15 years, the original pathology reviewed and those with carcinoma in situ (CIS) or dysplasia of the background urothelium excluded. Only 5 patients progressed over the whole follow-up period, giving an overall progression rate of 3%. Solitary tumours had an annual initial recurrence risk (AIR) of 0.23 in the first year; after the first year the AIR fell to approximately 0.1 but did not fall significantly in subsequent years up to 8 years. Of the 45 patients with multiple tumours, 32 suffered recurrences within the first year (AIR 0.71). Tumour grade did not influence either recurrence or progression. The results indicate that for solitary pTa tumours, less frequent endoscopic follow-up is justified but some continued surveillance after 5 disease-free years is necessary. The estimated risk of recurrence is a useful factor to consider when planning follow-up.  相似文献   
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Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns.  相似文献   
33.
Transabdominal versus endovaginal pelvic sonography: prospective study   总被引:1,自引:0,他引:1  
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.  相似文献   
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Intravenous digital subtraction renal angiography (DSRA) has been compared with conventional angiography only in small, selected series of hypertensive patients. The authors prospectively examined with intravenous DSRA 94 patients at increased risk for renovascular hypertension and compared these studies with conventional angiography. A stenosis of at least one main renal artery was identified with intravenous DSRA in 22 patients and confirmed in 20 patients. No significant stenoses were seen with conventional angiography in any of the 64 patients in whom lesions were not seen with intravenous DSRA. Since inadequate DSRA studies were considered positive for renal artery stenosis, the sensitivity of intravenous DSRA was 100% (25 of 25); specificity, 93% (64 of 69); positive predictive value, 83% (25 of 30); and negative predictive value, 100% (64 of 64). The authors conclude that intravenous DSRA is a sensitive test for identifying stenosis of the main renal arteries and is appropriate to use as a screening test among patients at increased risk for renovascular hypertension.  相似文献   
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There is evidence to suggest that histamine is a neurotransmitter in the CNS and functions in the regulation of arg-vasopressin (AVP) secretion. The posterior pituitary contains high levels of histamine and histamine N-methyltransferase (HNMT). Therefore, posterior pituitary histamine could also modulate the release of AVP. Paralleling the effect on AVP levels, the concentration of histamine in the rat posterior pituitary decreased from 18.8 +/- 2.7 ng/mg protein (x +/- SEM) to 12.9 +/- 1.9 ng/mg protein following 2 days of 2% (w/v) hypertonic saline administration and to 11.5 +/- 0.9 ng/mg protein with 7 days of treatment. Conversely, posterior pituitary HNMT activity was significantly elevated after hypertonic saline administration. Pituitary stalk transection did not reduce the concentration of histamine in the rat posterior pituitary although HNMT activity was reduced from 18.8 +/- 0.82 munits/gland to 9.22 +/- 1.56 munits/gland (x +/- SEM). These results indicate that histamine released from posterior pituitary mast cells could facilitate AVP release as part of the overall mechanism for osmotic stimulation of AVP secretion and support the concept that most posterior pituitary histamine is not neuronally derived from the brain. HNMT, on the other hand, may be contained in neurons disrupted by stalk section.  相似文献   
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