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61.
A prospective randomized study was conducted comparing two conditioning regimens for the treatment of patients with chronic myeloid leukemia in chronic phase by marrow transplantation from HLA identical siblings. Sixty-nine patients received 60 mg/kg of cyclophosphamide on each of 2 successive days followed by 6 fractions of total body irradiation each of 2.0 Gy (CY-TBI), and 73 patients received 16 mg/kg of busulfan delivered over 4 days followed by 60 mg/kg CY on each of 2 successive days (BU-CY). There was no significant difference between the CY-TBI and the BU-CY groups in the 3-year probabilities of survival (0.80 for both), relapse (0.13 for both), or event-free survival (CY-TBI, 0.68; BU-CY, 0.71) or in speed of engraftment or incidence of venocclusive disease of the liver. The 4-year probabilities of survival and event- free survival for patients transplanted within 1 year of diagnosis were 0.86 and 0.72, respectively, for each group. Significantly more patients in the CY-TBI group experienced major creatinine elevations. There was significantly more acute graft-versus-host disease in the CY- TBI group. Fever days, positive blood cultures, hospitalizations, and inpatient hospital days were significantly more common in the CY-TBI group than in the BU-CY group. In conclusion, the BU-CY regimen was better tolerated than, and associated with survival and relapse probabilities that compare favorably with, the CY-TBI regimen.  相似文献   
62.
Rheologic predictors of the severity of the painful sickle cell crisis   总被引:4,自引:0,他引:4  
Ballas  SK; Larner  J; Smith  ED; Surrey  S; Schwartz  E; Rappaport  EF 《Blood》1988,72(4):1216-1223
Deformable sickle erythrocytes have been reported by Mohandas and Evans to be more adherent to vascular endothelium than rigid irreversibly sickled cells (ISC). To define the clinical implications of this finding we have determined genetic, hematological, clinical, and rheological characteristics of sickle erythrocytes obtained from 65 patients with sickle cell anemia and fetal hemoglobin (Hb F) levels less than 15%. The alpha-globin gene number had a significant effect on the hematological parameters, the percentage of dense cells, ISC number, and HB A2 levels. The presence or absence of alpha thalassemia, however, had no effect on the frequency and severity of the sickle cell painful crisis (r = 0.06, P greater than .05). RBC deformability, determined by an ektacytometer, showed great heterogeneity among patients with three or four alpha-globin genes. Linear regression analyses of the data showed significant positive correlation of the frequency and severity of the painful crisis with RBC deformability (r = 0.49, P less than .001), and negative correlations with the percentage of dense cells (r = -0.37, P = .002), and the percentage of ISC (r = -0.46, P less than .001). We propose that the more deformable the sickle RBC are, the greater their adherence to vascular endothelium, and the more they cause vaso-occlusive crises, RBC deformability and the percentage of dense cells (or ISC) seem to have a predictive value of the frequency and severity of painful crises in sickle cell anemia.  相似文献   
63.
The antipyretic effect of single doses of alpha-methyl-4-(2-thienylcarbonyl)-phenyl acetic acid (suprofen, Suprol) syrup, administered at dose levels of 1, 2, 3, 4, 5, 7.5, and 10 mg/kg b.w., was tested in a randomized double-blind and a subsequent open study. The test populations consisted of 100 children in the double-blind study and 40 patients in the open test (20 subjects/group). The patients' age ranged from 2 to 12 years; the lowest initial rectal temperature was 39.0 degrees C. The treatment groups were homogeneous as to demographic data. The temperature was reduced in all treatment groups. In the double-blind study the mean value dropped under the subfebrile threshold of 38.0 degrees C only in the group on 5 mg/kg and remained then constant for up to 6 h following administration. No sufficient antipyretic effect was obtained with lower doses. The results of the additional open study with doses of 7.5 and 10 mg/kg indicated good antipyretic effect. This effect was not, however, superior to that obtained with 5 mg/kg. Pulse and respiratory rates returned to normal within 1.5 h following administration, except in patients on 1 mg/kg. A total of 10 patients, homogeneously distributed in the treatment groups, experienced vomiting as an adverse reaction. Short-term hypotonia was seen in one subject on 7.5 mg/kg. The results obtained show that single doses of suprofen upward of 5 mg/kg b.w. exert satisfactory, long-lasting, antipyretic effect on children.  相似文献   
64.
Rigby  WF; Ball  ED; Guyre  PM; Fanger  MW 《Blood》1985,65(4):858-861
Interferons (IFNs) have been shown to have significant effects on hematopoietic cell growth. Previous studies defining these effects have utilized mouse and human alpha-, beta-, and gamma-IFN isolated from supernatants of stimulated cells. Despite purification, the possible presence of other lymphokines and soluble factors remains a concern. In this study, the effects of gene-cloned alpha- and gamma-IFN on colony- forming units of granulocyte/macrophage (CFU-GM) progenitors cultured from the peripheral blood of normal volunteers were examined. In addition, blast cell colonies from one patient with acute myelogenous leukemia (AML) were studied. The growth of normal CFU-GM and AML blast cell colonies was inhibited in a dose-dependent manner by gamma- and alpha-IFN. gamma-IFN was ten to 100 times more potent than alpha-IFN in that this species of IFN reduced colony formation by greater than 50% at concentrations of less than 15 antiviral U/mL. The effects of gamma- IFN were neutralized by a monoclonal antibody specific for gamma-IFN. These in vitro studies indicate that human gamma-IFN may be an important modulator of myelopoiesis. Although these data indicate a possible efficacy of gamma-IFN in the treatment of AML, the in vitro results should be considered for their in vivo significance.  相似文献   
65.
Inflammatory carcinoma of the breast   总被引:2,自引:0,他引:2  
Barker  JL; Nelson  AJ; Montague  ED 《Radiology》1976,121(1):173
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66.
Group A streptococcus (GAS) is an important cause of morbidity and mortality worldwide. Surveillance of emm types has important implications, as it can provide baseline information for possible implementation of vaccination. A total of 1,349 GAS pediatric isolates were collected during a 7-year period (2007 to 2013); emm typing was completed for 1,282 pharyngeal (84%) or nonpharyngeal (16%) isolates, and emm clusters and temporal changes were analyzed. Thirty-five different emm types, including 14 subtypes, were identified. The most prevalent emm types identified were 1 (16.7%), 12 (13.6%), 77 (10.9%), 4 (10.8%), 28 (10.4%), 6 (6.8%), 3 (6.6%), and 89 (6.6%), accounting for 82.3% of total isolates. Rheumatogenic emm types comprised 16.3% of total isolates. The emm types 12, 4, and 77 were more prevalent among pharyngeal isolates, and the emm types 1, 89, 6, 75, and 11 were more prevalent among nonpharyngeal isolates. The emm types identified belonged to 13 emm clusters, and the 8 most prevalent clusters comprised 97% of all isolates. There were statistically significant decreases in the prevalence of emm types 12, 4, 5, and 61 and increases in the prevalence of emm types 89, 75, and 11, compared with the period 2001 to 2006. The proposed 30-valent GAS vaccine, which is currently in preclinical studies, encompasses 97.2% of the emm types detected in our study and 97.4% of the erythromycin-resistant strains. In addition, it includes 93.3% of the emm types involved in bacteremia. A much greater diversity of GAS emm types was identified in our area than described previously. Seasonal fluctuations and the introduction of new emm types were observed. Continuous surveillance of emm types is needed in order to evaluate the possible benefits of an M protein-based GAS vaccine.  相似文献   
67.
Clinical guidelines for instituting pharmacotherapy for the primary prevention of atherosclerotic cardiovascular disease (ASCVD), specifically lipid management and aspirin, have long been based on absolute risk. However, lipid management in the current era remains challenging to both patients and clinicians in the setting of somewhat discordant recommendations from various organizations. All guidelines endorse the use of statins for primary prevention for those at sufficient absolute risk, and treatment recommendations are generally “risk-based” rather than exclusively targeting specific low-density lipoprotein cholesterol levels. Nonetheless, guidelines differ in relation to the risk threshold for initiation and the intensity of statin treatment. The key concept of the clinician-patient risk discussion introduced in the 2013 American College of Cardiology/American Heart Association cholesterol guidelines is a process that addresses the potential for ASCVD risk reduction with statin treatment, potential for adverse treatment effects, patient preferences, encouragement of heart-healthy lifestyle, and management of other risk factors. However, operationalizing the clinician-patient risk discussion requires effective communication of the most accurate and personalized risk information. In this article, we review our treatment approach for the appropriate use of coronary artery calcium testing in the intermediate-risk patient to guide shared decision making. The decision to initiate or intensify statin therapy may be uncertain across a broad range of estimated 10-year ASCVD risk of 5% to 20%, and coronary artery calcium testing can reclassify risk upward or downward in approximately 50% of this group to inform the risk discussion. We conclude with 2 case-based examples of uncertain risk and uncertain statin therapeutic benefit to illustrate execution of the clinician-patient risk discussion.  相似文献   
68.
In 2006, the Centers for Disease Control and Prevention (CDC) released revised recommendations for performing human immunodeficiency virus (HIV) testing in health care settings, including implementing routine rapid HIV screening, the use of an integrated opt-out consent, and limited prevention counseling. Emergency departments (EDs) have been a primary focus of these efforts. These revised CDC recommendations were primarily based on feasibility studies and have not been evaluated through the application of rigorous research methods. This article describes the design and implementation of a large prospective controlled clinical trial to evaluate the CDC's recommendations in an ED setting. From April 15, 2007, through April 15, 2009, a prospective quasi-experimental equivalent time-samples clinical trial was performed to compare the clinical effectiveness and efficiency of routine (nontargeted) opt-out rapid HIV screening (intervention) to physician-directed diagnostic rapid HIV testing (control) in a high-volume urban ED. In addition, three nested observational studies were performed to evaluate the cost-effectiveness and patient and staff acceptance of the two rapid HIV testing methods. This article describes the rationale, methodologies, and study design features of this program evaluation clinical trial. It also provides details regarding the integration of the principal clinical trial and its nested observational studies. Such ED-based trials are rare, but serve to provide valid comparisons between testing approaches. Investigators should consider similar methodology when performing future ED-based health services research.  相似文献   
69.
Birth weight and the risk of testicular cancer: a meta-analysis   总被引:1,自引:0,他引:1  
The high incidence of testicular cancer in young males indicates a potential role of events during early life. Birth weight has been identified as a factor possibly associated with the risk of cancers later in life. To investigate the association between birth weight and testicular cancer, we conducted a Systematic Review and Meta-Analysis of published studies investigating the association between birth weight and testicular cancer. Data were combined using a fixed-effects model. Thirteen epidemiologic studies, published between 1983 and 2004, were included in the analysis, encompassing 5,663 patients with testicular cancer. Men weighing less than 2,500 grams at birth had a higher risk for developing testicular cancer later in life than those with normal birth weight (2,500-4,000 g) (OR = 1.18; 95% confidence interval (CI) 1.01-1.38). A similar trend was found for men with a birth weight above 4,000 g, (OR = 1.12; 95% CI 1.02-1.22). When seminoma and nonseminoma testicular cancer cases were considered separately, low birth weight was a risk factor specifically for seminomas (OR = 1.44; 95% CI 1.11-1.88). A U-shaped association was observed between birth weight and the risk for testicular cancer. The underlying biological mechanisms for this phenomenon remain to be elucidated.  相似文献   
70.
Suppurative corneal ulceration in Bangladesh   总被引:8,自引:0,他引:8  
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season.  相似文献   
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