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511.
512.
A woman who had received successful therapy for Wilm's tumor of one kidney in childhood developed renal cell carcinoma in the opposite kidney 21 years later. Such an occurrence has not been reported previously. A discussion of the differential diagnosis of calcified renal mass lesions and the angiographic differentiation between Wilms's tumor and renal cell carcinoma is presented. The possible relationship between these two primary renal tumors is considered.  相似文献   
513.
Miller  DL; O'Leary  TJ; Girton  M 《Radiology》1987,162(3):849-852
Radiography and microscopy were used to investigate the hepatic distribution of iodized oil injected into the hepatic artery in a rabbit VX2 tumor model. Iodized oil accumulates within hepatic metastases and in a ringlike fashion around them. Radiographic and histologic appearances were correlated, and it was concluded that ringlike deposition occurs in peritumoral sinusoids. There was no evidence that iodized oil is cleared by hepatic lymphatics. Early clearance of iodized oil into bile may possibly be caused by localized hepatic ischemia from oil microemboli or by direct phagocytosis by Kupffer cells. The remaining oil is washed through hepatic vasculature, circulates systemically, and is cleared by reticuloendothelial cells in lung, spleen, liver, and bone marrow. This mode of clearance, which has not been considered previously, may be important in the prediction of toxic effects caused by lipid and lipophilic antitumor agents administered via the hepatic artery.  相似文献   
514.
515.
Data are presented on nine patients with migraine by IHS criteria, recruited from those presenting to the clinic for treatment and needing prophylaxis. Pizotifen 0.5 mg tds was prescribed for 8 weeks and dispensed in special containers with an electronic event recorder concealed in the lid. This responded to the pressure change with each opening of the container and recorded it in real time. The information was later downloaded to a PC for analysis. At trial end, two patients had been lost to follow-up, one had not started the treatment at all, two had dropped out because of alleged side effects (drowsiness), and four patients had completed the study. For these, the quantity of tablets used as a percentage of that prescribed (i.e., compliance assessed on the basis of returned-tablet count) ranged from 62.6% to 91.9%;the percentage of days in which three doses had been taken ranged from only 15.8% to 79%; the percentage of doses taken on schedule (8 h ± 25% after the previous dose) ranged from 21.1% to 47.3%. It is possible that all evaluations of efficacy and tolerance of migraine prophylactics reported so far have been unsoundly based.  相似文献   
516.
Cardiac function: evaluation with fast-echo MR imaging   总被引:1,自引:0,他引:1  
Magnetic resonance (MR) imaging of the heart has, to date, been limited in its ability to evaluate cardiac function. The authors have implemented a technique for functional assessment of the heart using shorter echo times than those generally used for conventional spin-echo imaging. With these short echo times, multiple images can be obtained in a multisection mode approximately within the isovolumetric phases of the cardiac cycle. This permits a pair of image stacks to be obtained, one in end systole and the other in end diastole. With the use of a modified Simpson rule, left ventricular volume and ejection fraction were calculated and compared with results obtained from contrast material-enhanced ventriculography. Preliminary results indicate that this method has promise for the evaluation of a variety of functional parameters in the heart. The short acquisition times for this functional study permit it to be combined with a tissue characterization study within the time constraints of a clinical MR imaging session.  相似文献   
517.
A method for counting leukocytes in filtered components   总被引:1,自引:0,他引:1  
Leukocyte-depleted components are being used more frequently. Quantitation of residual WRCs is needed for quality control and for establishing the critical level required to prevent alloimmunization. Electronic counting is not accurate at WBC levels below 100/microL (1) and previously proposed techniques are either tedious or require sophisticated equipment. We describe a simple hemacytometer procedure using Türks solution that gives 87-93% recovery at WBC levels below 40/microL.  相似文献   
518.
Diffuse pleural thickening: percutaneous CT-guided cutting needle biopsy   总被引:2,自引:0,他引:2  
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519.
An experiment was conducted to test further the role of vasopressin in memory processes, using the learned helplessness paradigm as the memory testing situation. Mice treated intraventricularly with control rabbit serum immediately after an initial period of inescapable preshocks showed subsequent deficits in learning an escape task, a replication of the learned helplessness phenomenon. However, mice treated intraventricularly with antiserum to vasopressin after the initial inescapable shocks did not show later escape deficits. These findings are interpreted as supporting the suggestion that endogenous vasopressin is involved in long-term memory.  相似文献   
520.
Incidents of CLARE (contact lens induced acute red eye) are associated with high numbers of Gram-negative bacteria on the lens surface. This study found that most strains of bacteria implicated in CLARE adhere poorly to the lens surface regardless of whether the lens surface was clean or had been worn in the eye. The high numbers of bacteria on the lens surface result from bacterial growth on the lens surface after adhesion has occurred. Using an artificial tear formulation and real tears, this study demonstrated that the tear fluid provides the necessary nutrients required for bacterial growth.  相似文献   
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