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991.
Steven J. Weisholtz Barry J. Hartman Richard B. Roberts 《The American journal of medicine》1983,75(2):199-205
The hospital records of 264 patients with 277 episodes of pneumococcal bacteremia occurring at New York Hospital-Cornell Medical Center over the period 1970 to 1980 were examined to determine whether serotype distribution varied with the underlying disease or age of the patient. The patients were placed into three groups according to their underlying disease. Group A consisted of all patients with significant impairment of their immune system. Group B included those patients with underlying conditions that were not associated with immune deficiency. Group C comprised those patients considered to be normal hosts. Overall, 84 percent of blood isolates were serotypes included in the vaccine. In Group A, only 73 percent of these isolates were vaccine types, compared with 85 percent in Group B and 97 percent in Group C (differences significant at p < 0.001). Vaccine serotypes were more common in children than adults (92 versus 81 percent), but in analysis that controlled for underlying disease, the elderly did not differ from younger adults in serotype distribution. The apparent predilection of nonvaccine serotypes to cause bacteremia in immunocompromised patients may be one factor limiting vaccine efficacy in this high-risk population. 相似文献
992.
What Do Patients Want? 总被引:2,自引:2,他引:2
Solomon MJ Pager CK Keshava A Findlay M Butow P Salkeld GP Roberts R 《Diseases of the colon and rectum》2003,46(10):1351-1357
PURPOSE: Clinicians often make decisions for their patients, despite evidence that suggests that correspondence between patient and clinician decision making is poor. The management of colorectal cancer presents difficult decisions because the impact of treatment on quality of life might overshadow its survival efficacy. This study investigated whether patients are able to trade survival for quality of life as a means to express their preference for treatment options and to compare their preferences with those expressed by clinicians. METHODS: Patients undergoing curative surgery for colorectal cancer were interviewed postoperatively to elicit their preferences in four hypothetical treatment scenarios. A questionnaire was mailed to all Australian colorectal surgeons and medical oncologists that asked them to respond as if they themselves were patients. RESULTS: One hundred patients (91 percent), 43 colorectal surgeons (77 percent), and 103 medical oncologists (50 percent) participated. In all four scenarios, patients were able to trade survival for quality of life. Patients' responses varied between scenarios, both in willingness to trade and the average amount traded. There were significant differences between patients and clinicians. Clinicians were more willing than patients to trade survival to avoid a permanent colostomy in favor of chemoradiotherapy. Patients' strongest preference was to avoid chemotherapy, more than to avoid a permanent colostomy. CONCLUSIONS: Patients are able to trade survival as a measure of preference for quality of life and can do so differentially between treatment scenarios. Patients' preferences do not always accord with those of clinicians. Unless patients' preferences are explicitly sought and incorporated into clinical decision making, patients may not receive the treatment that is best for them. 相似文献
993.
B. A. J. Walters R. Stafford R. K. Roberts E. Seneviratne 《Internal medicine journal》1982,12(3):255-258
Abstract: Contamination and crossinfection with Clostridium difficile in an intensive care unit. B.A.J. Walters, R. Stafford, R. K. Roberts and E. Seneviratne, Aust. N.Z. J. Med., 1982, 12, pp. 255–258. An outbreak of pseudomembranous colitis in an intensive care unit is described. This resulted in environmental contamination by Clostridium difficile. The outbreak could be traced to one patient who received several antibiotics over the preceding three months. A search was conducted for asymptomatic carriers among patient and staff but none were found. Aquisition of C. difficile from inanimate environmental sources was the most probable means of transmission of the organism. Its persistence in the hospital environment for several weeks, most likely as spores, suggests that patients who develop pseudomembranous colitis should be isolated, especially in areas of high antibiotic usage. 相似文献
994.
M P Malee K M Malee S D Azuma R N Taylor J M Roberts 《The Journal of clinical endocrinology and metabolism》1992,74(5):1095-1100
Atrial natriuretic peptide (ANP) concentrations are typically elevated in hypervolemic states. However, ANP levels have been reported to be increased in the peripartum period in women with preeclampsia, a disorder characterized by central hypovolemia. We postulated that ANP levels are elevated in preeclamptic patients before clinically evident disease. ANP concentrations were determined in three groups: uncomplicated pregnancies, pregnancies complicated by preeclampsia, and non-pregnant reproductive-aged women. The former groups were matched for gestational age at plasma sampling and delivery. The plasma samples, obtained prospectively from each patient during the first, second, and third trimesters and within 72 h postpartum, were frozen before RIA. A significant gestational increase in ANP was noted in both groups of pregnant women, with third trimester levels exceeding first trimester levels (P less than 0.05). Consistent with previous reports, ANP levels were elevated in overtly preeclamptic patients vs. matched controls in the third trimester. The ANP concentration was also significantly increased during the second trimester in women destined to develop preeclampsia. Postpartum ANP values decreased in the preeclamptic group to approach the level in normal patients postpartum. Thus, it appears that the stimuli of ANP secretion differ in uncomplicated and preeclamptic patients. Moreover, an elevation of plasma ANP is detectable before the onset of clinical evidence of preeclampsia. 相似文献
995.
C D Morgan R S Roberts A Haq R S Baigrie P A Daly M Gent P W Armstrong 《Journal of the American College of Cardiology》1991,17(7):1451-1457
Infarct size, left ventricular function and infarct-related coronary artery patency were examined in 108 patients who took part in a previously reported placebo-controlled trial of recombinant tissue-type plasminogen activator (rt-PA) in acute myocardial infarction. Coronary angiography was performed 17 +/- 0.8 h after initiation of treatment in 47 patients (group A) or at 10 days in 61 patients (group B). Both groups underwent radionuclide ventriculography 3.8 +/- 0.8 h and again on day 9 after treatment and quantitative thallium scintigraphy on day 8. In group A, the infarct-related artery was patent in 53%; these patients had a smaller global (15.1 +/- 2.5% vs. 25.7 +/- 4.7%, p = 0.029) and regional (14.7 +/- 2.5% vs. 24.1 +/- 4.7%, p = 0.044) fixed thallium defect than did those with an occluded artery. Infarct regional ejection fraction improved by 10.1 +/- 2.1% between early and late studies when the infarct-related artery was patent and by 4.8 +/- 1.4% if it was occluded (p = 0.048); changes in global and noninfarct regional ejection fraction were similar irrespective of perfusion status. Infarct regional ejection fraction and fixed thallium defect were inversely related only when the infarct-related artery was occluded (r = -0.83, p less than 0.0001). In group B, 10 day patency of the infarct-related artery was 67%; there was no difference in patency by treatment assignment or in left ventricular function or infarct size between patients with and without infarct-related artery patency. There was no evidence of an effect of rt-PA therapy beyond that expressed through coronary patency alone in either group A or group B. 相似文献
996.
G B Habib J Heibig S A Forman B G Brown R Roberts M L Terrin R Bolli 《Circulation》1991,83(3):739-746
BACKGROUND. The influence of coronary collateral vessels on infarct size in humans remains controversial, partly because no previous study has examined the impact of collaterals present at the onset of acute myocardial infarction on infarct size. METHODS AND RESULTS. The present study used the data base of the Thrombolysis in Myocardial Infarction (TIMI) Phase I trial to correlate the presence or absence of angiographically documented collaterals in the initial hours of myocardial infarct evolution with the size of the infarct as assessed by serial measurements of serum creatine kinase (CK). To avoid the confounding effects of reperfusion on enzymatic estimates of infarct size, this report is limited to those 125 patients who failed to recanalize at 90 minutes after administration of tissue plasminogen activator or streptokinase. Patients with angiographically documented collaterals (group A, n = 51) had significantly lower values of peak serum CK than patients without collaterals (group B, n = 74) (1,877 +/- 216 versus 2,661 +/- 212 IU/l, respectively [mean +/- SEM], p = 0.004). Similarly, CK-derived infarct size estimates were significantly lower in group A than in group B (20.6 +/- 2.5 versus 31.4 +/- 2.8 CK gram equivalents, p = 0.001). The infarct size observed in patients with collaterals was less for anterior infarctions as well as for infarctions of other locations; thus, the beneficial effects of collaterals were independent of the site of the infarct. In 65 of the 125 patients who failed to reperfuse, left ventricular ejection fraction (LVEF) was assessed by contrast ventriculography both at initial cardiac catheterization (before thrombolytic therapy) and at hospital discharge. Among the patients who had both studies, global LVEF tended to increase from pretreatment to hospital discharge in group A (from 50.6 +/- 1.8% to 53.4 +/- 1.8%, p = 0.10) but decreased in group B patients (from 50.3 +/- 1.8% to 47.8 +/- 1.7%, p = 0.02). At hospital discharge, global LVEF was greater in patients with coronary collaterals (53.5 +/- 1.7% versus 49.6 +/- 1.7%, p = 0.01). CONCLUSIONS. The results demonstrate that, in patients in whom thrombolytic therapy fails to induce reperfusion, the presence of coronary collateral vessels at the onset of myocardial infarction is associated with limitation of infarct size as assessed enzymatically and with improved ventricular function on discharge as assessed by LVEF. 相似文献
997.
Absence of cytomegalovirus-resistance mutations after valganciclovir prophylaxis, in a prospective multicenter study of solid-organ transplant recipients 总被引:11,自引:0,他引:11
Boivin G Goyette N Gilbert C Roberts N Macey K Paya C Pescovitz MD Humar A Dominguez E Washburn K Blumberg E Alexander B Freeman R Heaton N Covington E 《The Journal of infectious diseases》2004,189(9):1615-1618
We investigated the emergence of cytomegalovirus (CMV) ganciclovir-resistance mutations in 301 high-risk solid-organ transplant (SOT) recipients after oral prophylaxis, for 100 days, with either valganciclovir or ganciclovir. For patients treated with ganciclovir, the incidence of CMV UL97 mutations was 1.9% (2/103) at the end of prophylaxis and 6.1% (2/33) for patients with suspected CMV disease up to 1 year after transplantation. No resistance mutations were detected in samples from valganciclovir-treated patients. Dual polymerase (UL54) and UL97 resistance mutations were not seen. Valganciclovir was associated with negligible risk of resistance and thus constitutes a useful alternative to ganciclovir prophylaxis for CMV in high-risk SOT recipients. 相似文献
998.
Soriano-Guillén L Barrios V Martos G Chowen JA Campos-Barros A Argente J 《European journal of endocrinology / European Federation of Endocrine Societies》2004,151(1):119-121
OBJECTIVE: Coexpression of GH secretagogue receptor and ghrelin in the pancreas suggests that this peptide is involved in glucose metabolism. Previous reports in adult humans have demonstrated that plasma ghrelin levels decrease after oral glucose administration. However, no data are available in children. Therefore, the aim of this study was to analyze the response of plasma ghrelin levels in obese children after oral glucose administration. SUBJECTS AND METHODS: Twenty-eight obese children ranging from Tanner I to Tanner V were studied. All subjects were given 0.75 g/kg (maximum 75 g) glucose solution after overnight fasting. Ghrelin, insulin, glucose and IGF-binding-protein-1 were determined at 0, 30, 60 and 120 min of the oral glucose tolerance test (OGTT). RESULTS: Basal plasma ghrelin levels were significantly lower than in the respective control groups. These levels decreased significantly during OGTT in obese children, reaching a nadir of 28+/-9% at 60 min in parallel with the maximum increase in glucose levels and previous to maximum insulin levels. CONCLUSION: The rapid fall in plasma ghrelin concentration in obese children after glucose load suggests a mechanism for the control of appetite after food intake. 相似文献
999.
Digital radiography and display systems have revolutionized radiologic practice in recent years and have enabled clinical application of advanced image processing techniques. These include dual energy subtraction and temporal subtraction, both of which can improve diagnostic accuracy for abnormal findings in chest radiographs, especially for subtle lesions such as early lung cancer or focal pneumonia. Dual energy radiography exploits the differential attenuation of low-energy x-ray photons by calcium to produce separate images on the bones and soft tissues, which provides improved detection and characterization of both calcified and noncalcified lung lesions. Dual energy subtraction radiography is currently available from 2 of the major vendors and is in clinical use at many institutions in the United States. Temporal subtraction is a complementary technique that enhances interval change, by using a previous radiograph as a subtraction mask, so that unchanged normal anatomy is suppressed, whereas new abnormalities are enhanced. Though it is not yet a product in the United States, temporal subtraction is available for clinical use in Japan. Temporal subtraction can be combined with energy subtraction to reduce misregistration artifacts, and also has potential to improve computer-aided detection of nodules and other types of lung disease. 相似文献
1000.