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41.
PURPOSETo evaluate the effect of MR contrast dose versus delayed imaging time on the detection of metastatic brain lesions based on lesion size.METHODSContrast MR examinations with gadoteridol were obtained in 45 patients with brain metastases. The patients were divided into two groups: 16 received cumulative standard dose (0.1 mmol/kg) and 29 received cumulative triple dose (0.3 mmol/kg). Both groups were evaluated at two dose levels (lower dose and higher dose) with two separate injections. Each patient received an initial bolus injection of either 0.05 (cumulative standard dose) or 0.1 (cumulative triple dose) mmol/kg of gadoteridol to reach the lower-dose level and underwent imaging immediately and 10 and 20 minutes later. Thirty minutes after injection, an additional bolus injection of 0.05 (cumulative standard dose) or 0.2 (cumulative triple dose) mmol/kg was administered to reach the cumulative higher-dose level (cumulative standard dose, 0.1 mmol/kg; cumulative triple dose, 0.3 mmol). Images were acquired immediately.RESULTSThere was no difference in the detection rate for lesions larger than 10 mm among T2-weighted, lower-dose immediate and delayed, or immediate higher-dose images in both study groups. Lesions smaller than 10 mm had improved detection with delayed imaging in both study groups; however, the immediate higher-dose studies still had the highest detection rate.CONCLUSIONIn the evaluation of small central nervous system metastases, either delayed imaging after the injection of standard contrast dose or higher contrast dose may improve their detection, and therefore affect clinical management. Higher contrast dose (cumulative triple dose) studies appear to be more effective than delayed imaging with standard dose.  相似文献   
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43.
Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis, but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer, with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations (275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment of suramin’s activity in hormone-refractory prostate cancer. Received: 9 June 1995/Accepted: 18 March 1996  相似文献   
44.
Low-income minority patients from East St. Louis, Illinois, a depressed midwestern urban city, who had visited acute care settings with asthma symptoms, participated in a focus group. Questions were constructed around the Health Belief Model to characterize participants' experiences in receiving asthma care, their confidence in long-term asthma self-management, barriers they perceived to managing their asthma, and recommendations they would make for improving asthma care in their community. Analysis of comments suggests an appreciable understanding of asthma triggers, limited coping behaviors for asthma symptoms, very limited practice of active asthma management, perception of the health care system as frequently insensitive to their needs or their knowledge of their own care, exchange of well-articulated information regarding how to deal with the system, and an apparent lack of awareness of any potential contribution of patient education or support system.  相似文献   
45.
Neutrophil bactericidal activity was assessed in patients with type 1 (n=45) and Type 2 diabetes mellitus (n=68) and non-diabetic control subjects (n=40) by measurement of whole blood chemiluminescence. Though chemiluminescence values tended to be highest in the non-diabetic subjects these differences were not statistically significant (mean ± SD) (2.73 ± 1.65 mV (controls), 2.33 ± 1.41 mV (Type 1 diabetes) and 2.38 ± 1.12 mV (Type 2 diabetes), F=1.12, p=0.33). Significant negative correlations were evident, however, in patients with both Type 1 and Type 2 diabetes between chemiluminescence and glycated haemoglobin (rs=-0.35, p=0.005 (Type 1), rs=-0.45, p=0.002 (Type 2), fructosamine (rs=-0.36, p=0.003 (Type 1), rs=-0.42, p=0.004 (Type 2)), and random blood glucose (rs=-0.25, p=0.04 (Type 1), rs=-0.48, p=0.001 (Type 2)). Changes in whole blood chemiluminescence in a further group of 10 patients with Type 2 diabetes mellitus commenced on insulin therapy were followed for 21 days. Serum fructosamine concentrations fell significantly over this time (524 ± 58 μmol l?1 to 405 ± 47 μmol l?1, p<0.001), however, although chemiluminescence values tended to rise these changes were not statistically significant (1.01 ± 0.38 mV to 1.60 ± 0.91 mV, S=4.24, df=5, p=0.52). These results suggest that impaired neutrophil bactericidal function is associated with poor blood glucose control. While it is likely that neutrophil bactericidal function will improve as blood glucose control improves, further studies are required both to confirm this and to demonstrate a reduction in the incidence of clinical bacterial infection.  相似文献   
46.
Study Objective . To determine the influence of treatment on the microbiologic outcome of funguria. Design . Retrospective case series. Setting . A 300-bed tertiary care teaching hospital in a large metropolitan area. Subjects . 141 hospitalized patients, 18 years of age or older, with at least one urine culture positive (≥ 102 cfu/ml) for fungi. Interventions . Retrospective review of medical records to determine the microbiologic outcome of funguria. Main Results . Funguria developed rapidly in individuals with known predisposing factors. Urinalysis did not routinely detect the presence of fungi or pyuria. Symptoms such as fever, dysuria, and frequency were generally absent. Funguria persisted whether it was due to Candida albicans or non-albicans species. There were no statistical differences in the microbiologic outcomes of treated and untreated funguria. Conclusions . Funguria is a rapidly developing, often benign and persistent process. Minimizing predisposing risks, such as removing indwelling urinary catheters, is beneficial in its management. Pharmacologic treatment of funguria due to C. albicans or non-albicans species does not influence the microbiologic outcome.  相似文献   
47.
1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension.  相似文献   
48.
An ultra-short-time heating system was used to process blood plasma spiked with various viruses (HIV, vesicular stomatitis virus, encephalomyocarditis virus). Virus reduction and recovery of plasma proteins were measured at various temperatures from 65 to 85 degrees C. Processing at 77 degrees C and 0.006 s resulted in a high level of virus kill, including greater than or equal to 4.4 log10 HIV, while maintaining protein structure and activity essentially intact.  相似文献   
49.
For almost three decades, many have regarded general hospital psychiatric units as the most appropriate setting for acute treatment of persons with serious mental illness who were once treated mostly in state hospitals. The extent to which this transfer has taken place and the differences between public and private general hospitals have been unclear. Using data from the 1988 National Mental Health Facilities Study and published data from the 1970s, the authors found that nearly half of all general hospitals providing psychiatric services treat persons with serious mental illness. Significant differences in case and payer mix were observed between public and private general hospitals, although these differences were smaller than in the 1970s. The findings suggest increased involvement by private general hospitals in treating patients reimbursed by public payers, but the findings also indicate that persons with serious mental illness and those using Medicaid are still more prevalent in public general hospitals than in private ones.  相似文献   
50.
In summary, the access coordinator is at the center of our access program at UAB. The coordinators can make decisions based on the calls we receive from the nursing staff and reports obtained from procedures. The ability to relay information to the entire team rather than simply data entry staff, makes us a central focal area for our access team. This type of model is working to help us achieve better patient outcomes. We provide many services but the most important is follow-up. As a result, we are able to achieve optimal outcomes for our patients.  相似文献   
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