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Polymorphonuclear leukocytes of 18 patients during 19 episodes of active bacterial infection produced increased chemiluminescence (mean +/- standard error [SE], 56.3 +/- 4.4 X 10(3) cpm) when the production was compared to that of 29 uninfected controls (35.3 +/- 2.4 X 10(3) cpm; P less than 0.01). Chemiluminescence production remained increased with persistent infection but fell to the levels of controls with appropriate therapy. Phagocytic uptake as determined with radiolabeled bacteria was increased, and chemotactic responsiveness was markedly enhanced in the patients (mean index +/- SE, 260 +/- 51) when these responses were compared with those of controls (77 +/- 18). Chemiluminescence and chemotactic activity correlated in the patients with bacterial infection (r = 0.76), but one function did not appear to depend upon the intactness of the other. The ratio of cyclic guanosine 3',5'-phosphate to cyclic adenosine 3',5'-hosphate in the polymorphonuclear leukocytes of patients with infections (mean +/- SE, 0.102 +/- 0.0008) was also significantly higher than in controls (0.067 +/- 0.007). These data indicate that the polymorphonuclear leukocytes of the majority of patients with active bacterial infection are in an activated state both functionally and metabolically.  相似文献   
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OBJECTIVE: To evaluate the histopathological outcome in patients with prostate cancer operated on with radical retropubic prostatectomy. MATERIAL AND METHODS: A total of 167 patients with clinically organ-localized prostate cancer treated with open radical retropubic prostatectomy between 1996 and 2001 were divided into three equally sized consecutive cohorts (cohorts I-III). The prostatectomy specimens were re-examined by two pathologists with respect to pathological tumour stage, tumour grade and surgical tumour margins. RESULTS: The mean preoperative prostate-specific antigen (PSA) value was statistically significantly higher in cohort I compared to cohorts II and III: 13.2, 9.0 and 8.5 ng/ml, respectively (p<0.05). The incidence of locally advanced (pT3a-3b) tumours was 44% in cohort I and 20% in both cohorts II and III (p<0.05). The incidence of positive tumour margins was 58% in cohort I, compared to 30% in cohort II and 13% in cohort III (p<0.05). The incidence of positive intracapsular tumour margins was 55% in cohort I, compared to 25% in cohort II and 8.9% in cohort III (p<0.05). The incidence of positive tumour margins in the pT2 tumours in cohorts I-III was 57%, 26% and 8.9%, respectively (p<0.05). Cohort III had significantly more low-grade tumours (Gleason score 4-6; 58.9%) compared to cohorts I (31.5%) and II (34%). There was a higher incidence of Gleason score >or=7 in the pT3 tumours compared to the pT2 tumours (80% vs 46%) and in margin-positive compared to -negative tumours (69.6% vs 48.6%) (p<0.05). CONCLUSIONS: The decline in pT3 tumours and positive tumour margins between cohorts I-III is probably due to a gradually more strict selection of patients for radical retropubic prostatectomy. The successive reduction in positive intracapsular tumour margins is most likely due to an improved surgical technique.  相似文献   
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The aim of this study was to develop a tool that can aid nurse managers in planning nurse staffing levels and assessing workload in hematology-oncology wards. A task-oriented method based on a time-and-motion study was used. Three general nursing procedures and 7 specific oncologic and hematologic activities were clocked. It was checked in the charts of the patient, for each day of the admission, how often selected nursing procedures were performed. Then total amount of time needed for each patient was calculated. Data from 29 admissions to the ward were analyzed and divided into 5 categories based upon the treatment performed during that admission. The categories chosen were: autologous stem cell transplantation, allogeneic stem cell transplantation, graft versus host reaction, leukemia treatment, and chemotherapy for solid neoplasm. The results obtained are an estimate of the different daily workload that is required for these categories of patients in selected nursing procedures.  相似文献   
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Thrombopoiesis is a multistage process beginning with pluripotent hematopoietic stem cells, progressing through proliferating cells committed to megakaryocytopoiesis, to megakaryocytes, and eventually ending with the shedding of platelets from megakaryocytes. Many growth factors stimulate thrombopoiesis; this review addresses those that act through binding to the thrombopoietin receptor. The cloning of thrombopoietin in 1994 greatly accelerated progress in understanding the biology of thrombopoiesis and of hematopoiesis in general. Detailed structural and functional studies of the thrombopoietin receptor, coupled with novel molecular pharmacology approaches, have led to new classes of thrombopoietic mimetics. Initial clinical trials with recombinant thrombopoietins faltered as they encountered significant neutralizing antibodies or difficulty finding a significant clinical niche in support of chemotherapy. Ongoing studies with the new thrombopoietic agents have invigorated the field, with positive results now reported in idiopathic thrombocytopenic purpura.  相似文献   
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Faced with a rapidly changing healthcare environment, primary care practices often have to change how they practice medicine. Yet change is difficult, and the process by which practice improvement can be understood and facilitated has not been well elucidated. Therefore, we developed a model of practice change using data from a quality improvement intervention that was successful in creating a sustainable practice improvement. A multidisciplinary team evaluated data from the Study To Enhance Prevention by Understanding Practice (STEP-UP), a randomized clinical trial conducted to improve the delivery of evidence-based preventive services in 79 northeastern Ohio practices. The team conducted comparative case-study analyses of high- and low-improvement practices to identify variables that are critical to the change process and to create a conceptual model for the change. The model depicts the critical elements for understanding and guiding practice change and emphasizes the importance of these elements' evolving interrelationships. These elements are (1) motivation of key stakeholders to achieve the target for change; (2) instrumental, personal, and interactive resources for change; (3) motivators outside the practice, including the larger healthcare environment and community; and (4) opportunities for change--that is, how key stakeholders understand the change options. Change is influenced by the complex interaction of factors inside and outside the practice. Interventions that are based on understanding the four key elements and their interrelationships can yield sustainable quality improvements in primary care practice.  相似文献   
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