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171.
We investigated in-hospital and long-term mortality in 16 patients with infective endocarditis and paravalvular abscess on a prosthetic valve (6 of whom underwent surgery) and in 12 patients with infective endocarditis and paravalvular abscess on a native valve (8 of whom underwent surgery). The only significant risk factor for in-hospital mortality in patients with prosthetic or native value paravalvular abscess was age (P < 0.001). In-hospital mortality was 33% in patients with prosthetic valve paravalvular abscess undergoing surgery and 33% in patients treated medically (P = not significant). In-hospital mortality was 25% in patients with native valve paravalvular abscess undergoing surgery and 25% in patients treated medically (P = not significant). At 4.8-year follow up, survival of patients with prosthetic valve paravalvular abscess was 67% for patients treated surgically versus 40% for patients treated medically (P = not significant). At 4.8-year follow up, survival of patients with native valve paravalvular abscess was 75% for patients treated surgically versus 50% for patients treated medically (P = not significant).  相似文献   
172.
Platelet functions such as aggregation and clot retraction are often abnormal in chronic mylogenous leukemia (CML) patients. However, the molecular mechanisms of these altered functions are unknown. As expression of the p210bcr-abl oncogene product, a constitutively active tyrosine kinase, is known to have an essential role in the pathogenesis of CML and tyrosine phosphorylation is intimately involved in various aspects of platelet activation, we examined the pattern of protein tyrosine phosphorylation in platelets from 15 CML patients by immunoblotting with a monoclonal antiphosphotyrosine antibody (4G10). Before and after stimulation with thrombin, the only consistent difference between normal and CML platelets was the presence of a tyrosine phosphorylated protein with a relative molecular weight of 39 kD. This tyrosine phosphorylated protein was identified as crid, an SH2, SH3 containing adapter protein. Thus, as previously demonstrated for neutrophils from CML patients, tyrosine phosphorylation of p39crkl persists in mature platelets. No tyrosine phosphorylation of crid was detected following stimulation with thrombin in normal platelets. However, crkl became incorporated into the Triton X-100 insoluble residue following thrombin stimulation in a manner dependent on platelet aggregation. Further, we found that crkl is an endogenous substrate for calpain, a protease that may be involved in postaggregation signaling processes. This suggests that crkl may be involved in the reorganization of the cytoskeleton during normal platelet aggregation and its tyrosine phosphorylation in CML platelets may contribute to the abnormal platelet function in CML patients. Finally, we found that thrombopoietin induces tyrosine phosphorylation of crk1 in normal platelets and FDCP cells genetically engineered to express human c-Mpl. This suggests that crk1 can be phosphorylated by a kinase other than p210bcr-abl and that crk1 may have a role in signaling by thrombopoietin.  相似文献   
173.
Adenocarcinoma of the prostate and rectum are common male pelvic cancers and may present synchronously or metachronously and, due to their anatomic proximity. The treatment of rectal or prostate cancer (in particular surgery and/or radiotherapy) may alter the presentation, incidence and management should a metachronous tumour develop. This review focuses on the interaction between prostatic and rectal cancer diagnosis and management. We have restricted the scope of this large topic to general considerations, management of rectal cancer after prostate cancer treatment and vice versa, management of synchronous disease and cancer follow-up issues.  相似文献   
174.
The purpose of this study was to investigate the circulatory responses to hypoglycaemia in diabetic and non‐diabetic children and to determine whether these changes were associated with hormone levels or clinical variables. Plasma glucose levels in 18 diabetic and 15 control children were gradually lowered to 2.5 (0.3)?mmol/L (mean (SD)) and 2.9 (0.2)?mmol/L, respectively. Blood pressure and heart rate were recorded at 10‐min intervals, and blood samples were taken for hormone analysis. Systolic pressure increased from 110.1 (10.0) to 115.0 (11.2)?mmHg (p=0.008) in the diabetic children and from 116.9 (12.0) to 121.6 (12.7)?mmHg (p=0.049) in the controls. Diastolic pressure decreased from 61.9 (6.7) to 55.5 (7.6)?mmHg (p<0.001) in the diabetic children and from 66.5 (6.3) to 55.1 (5.1)?mmHg (p<0.001) in the controls. The increase in pulse pressure during hypoglycaemia was significantly smaller in the diabetic children (10.6 (5.5) vs. 15.7 (7.7)?mmHg, p=0.04). The final systolic and pulse pressure correlated with the final adrenaline level in the controls (r=0.66, p=0.008 and r=0.70, p=0.003, respectively). In the non‐diabetic as well as the diabetic group, the increase in pulse pressure correlated with the increase in adrenaline (r=0.66, p=0.008 and r=0.50, p=0.03, respectively). It is concluded that systolic pressure increases and diastolic pressure decreases during hypoglycaemia in children. The smaller increase in pulse pressure observed in the diabetic children is probably related to a significantly smaller increase in adrenaline in this group.  相似文献   
175.
Brody  AS; Saks  BJ; Field  DR; Skinner  SR; Capra  RE 《Radiology》1986,160(1):269-271
During computed tomography (CT) pelvimetry of two pregnant women, bony abnormalities of the fetuses were noted on the scout images that were not confirmed at delivery. To explore the cause of these artifacts, specimen long bones were manipulated in various ways during CT scout imaging. Artifacts like those seen during in vivo imaging were found to be caused by motion of the object. The CT scout view is an example of an image produced by a digital system that uses a scanning beam. This type of digital system is being used for several types of body imaging including screening for scoliosis and chest radiography. Attention to motion artifacts should decrease diagnostic errors and aid further development of these systems.  相似文献   
176.
To define the causes, clinical significance and characteristics of headaches in HIV-1-related disorders, we studied 49 consecutive HIV-1 infected patients who presented with headache. Work-up included CT scans, cerebrospinal fluid examinations (in the absence of a contraindication) and serologic studies. Overall, 40 of 49 patients (82 percent) had an identifiable serious cause of headache. Cryptococcal meningitis (39 percent) and CNS toxoplasmosis (16 percent) were the leading headache etiologies. Serious causes were more likely in patients diagnosed with AIDS prior to presentation but also occurred in most patients in early stages of infection. Based on this study, we suggest that patients with HIV-1 infection must be managed with a high index of suspicion when they present with new onset headaches.  相似文献   
177.
OBJECTIVES: To study the cooperation of primary care physicians with a community-based prevention and health promotion program for older persons, to study physician factors related to cooperation, and to determine any relationship between physician cooperation and patient adherence to program recommendations and patient satisfaction with health care. DESIGN AND SETTING: A survey administered in subjects' homes and physicians' offices in Santa Monica, California. PARTICIPANTS: Patients (n = 81) were intervention group subjects in a 3-year, randomized, controlled trial of in-home comprehensive geriatric assessment paired with prevention and health promotion. Physicians (n = 50) were selected if they had been contacted at least once by a study nurse practitioner about one of these patients. MEASUREMENTS: Physician cooperation was rated by study nurse practitioners. Physicians were interviewed to identify factors associated with cooperation. Patients' satisfaction with health care and adherence were measured prospectively throughout the 3-year program. MAIN RESULTS: Physicians exhibiting better cooperation had fewer years in practice (P = .03) and were more likely to discuss the program with their patients (P = .005), see benefit for their patients from the program (P = .02), and rate program information as useful (P = .002). Higher physician cooperation did not predict higher patient satisfaction (P = .23) but did predict higher patient adherence to program recommendations (P = .02). CONCLUSIONS: Physicians rated as cooperative were more likely to have a positive appraisal of the program, and their patients had higher adherence to program recommendations. These findings suggest that strategies for increasing primary care physician cooperation might improve effectiveness of similar community-based prevention and health promotion programs.  相似文献   
178.
179.
W S Aronow 《Herz》1991,16(6):395-404
Thrombus formation in the left atrium and left ventricle is primarily due to stasis of blood which causes activation of the coagulation system. Migration of thrombotic material into the circulation depends on the dynamic forces of the circulation. Atrial fibrillation is the commonest underlying cardiac disorder predisposing to thromboembolism. Rheumatic mitral stenosis, left atrial enlargement, prior myocardial infarction, hypertension, and echocardiographic left ventricular hypertrophy are risk factors for thromboembolic stroke in elderly patients with chronic atrial fibrillation. Non-valvular atrial fibrillation accounts for 45% of cardiac sources of thromboembolic stroke and includes patients with ischemic heart disease, hypertension, thyrotoxic heart disease, hypertrophic cardiomyopathy, chronic sinoatrial disorder, and idiopathic atrial fibrillation. 15% of cardiac sources of thromboembolic stroke are associated with acute myocardial infarction, 10% with left ventricular aneurysm and mural thrombi remote from an acute myocardial infarction, 10% with rheumatic valvular heart disease, and 10% with prosthetic cardiac valves. Mitral valve prolapse, mitral annular calcium, nonischemic cardiomyopathies, infective endocarditis, nonbacterial thrombotic endocarditis, left atrial myxoma, paradoxical embolism associated with congenital heart disease, calcific aortic stenosis, and complex atherosclerotic plaque within the proximal aorta also contribute to thromboembolism.  相似文献   
180.
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