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91.
Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.  相似文献   
92.
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%).  相似文献   
93.
94.
Background: Physiotherapists (PTs) in primary health care provide services to preterm infants and their parents after hospital discharge. The service should be collaborative and individualized to meet the family’s needs. In this study, we analyze pediatric PTs’ collaborative work in the clinical setting and investigate the PTs’ emerging clinical reasoning (CR) in interaction with the infant and parent(s).

Methods: The study is based on observations of 20 physical therapy sessions and 20 interviews with PTs. We performed a systematic content analysis informed by enactive theory regarding the interactions and co-creation of meaning.

Results and Discussion: CR emerged in reciprocity with the PTs’ interaction with the infant and parent(s). Based on the sensitivity to the infant’s motor abilities and signs of engagement as well as the parents’ need of support and education, the PTs individualized and reasoned about their therapeutic approach. This interactional CR was vulnerable: infant disengagement, parent expectations, and PT preoccupations could obfuscate interactions and hamper CR.

Conclusion: Through mutuality and engagement with the infant and parent(s), the PTs allow the autonomy of interaction to emerge and shape the translation of CR into successful therapeutic actions and learning together with the infant and parent(s).  相似文献   

95.
96.
A policy of selective implantation of drug eluting stents, in a minority of lesions most likely to benefit, seems to be a rational way to employ this new and currently costly technology.  相似文献   
97.
Background: In myocardial infarction patients undergoing thrombolysis, treatment delays negatively impact outcomes. This pilot study was conducted to determine the feasibility and timing of field administration of intravenous double bolus reteplase in patients with ST-elevation myocardial infarction. Methods: Sixty three patients with symptoms and EKG changes consistent with acute myocardial infarction of less than six hours duration received the first bolus of reteplase before arriving at the emergency department. A second bolus of reteplase was given in the emergency department. Subsequent resolution of ST-segment elevation was measured. Mean time from symptom onset to paramedic dispatch, and paramedic arrivals to first bolus of reteplase were measured. The mean time from the first bolus of reteplase to heparin bolus in an emergency department was also measured. All patients with evidence of ST-elevation and suspected acute myocardial infarction gave consent for the thrombolytic therapy. There were no refusals of therapy among those candidates eligible for thrombolysis. Results: The mean times from the first bolus of reteplase to heparin bolus in the emergency department was substantially longer than the in-field times. Resolution of ST-segment elevation was recorded in 52 of the 63 patients and the times of resolution ranged from five minutes after the first bolus dose to 190 minutes after the second bolus of reteplase. Resolution of ST-segment elevation and relief of pain occurred almost simultaneously. Conclusions: These results demonstrated that in-field administration of thrombolytic therapy is a viable option to reduce the delay from symptom onset to initiation of thrombolysis. They demonstrated that satisfactory resolution of ST-segment elevation can be recorded in the field. The reduction in mortality observed in this study is comparable to previously published studies on inpatients. Abbreviated Abstract. This open-label pilot study was conducted to determine the feasibility and timing of field administration of intravenous double-bolus reteplase and to measure subsequent resolution of ST elevation in 63 patients with symptoms and ECG changes consistent with acute myocardial infarction for less than 6 hours. These results demonstrated that in-field administration of thrombolytic therapy is a viable option to reduce the delay from symptom onset to initiation of thrombolytic therapy.  相似文献   
98.
Cassileth  PA; Suholet  D; Cooper  RA 《Blood》1981,58(2):237-243
The HL-60 leukemia cell line derived from a human acute promyelocytic leukemia is stimulated to differentiate into macrophages within 24-28 hr after exposure to the phorbol ester, 12-O-tetradecanoylphorbol-13- acetate (TPA). We studied early alterations (within 90 min of exposure to TPA) in phosphatidylcholine metabolism in HL-60 cells and found that phosphatidylcholine synthesis by methylation is phosphatidylethanolamine was inhibited in a dose-dependent fashion. In contrast, synthesis of phosphatidylcholine from endogenous choline was enhanced and correlated inversely with the degree of inhibition of the methylation pathway. Phorbol ester congeners of TPA caused similar alterations in phosphatidylcholine metabolism in direct relationship to their capacity to induce differentiation in HL-60 cells. Perturbation of phosphatidylcholine metabolism is an early membrane even in TPA- induced HL-60 cell differentiation.  相似文献   
99.
AIMS/HYPOTHESIS: This study was performed to evaluate the influence of ethnicity and socioeconomic status (SES) on metabolic control in a population-based cohort of children with type 1 diabetes mellitus, and to evaluate whether any relationship between ethnicity and HbA(1c) is mediated by SES. METHODS: We performed a retrospective review of all patients under age 16 years with type 1 diabetes (n = 555) from 1995 to 2005 in the greater Auckland region, New Zealand. Diabetes care variables and HbA(1c) values were collected prospectively, during clinic visits. RESULTS: The mean population HbA(1c) was 8.3 +/- 1.3%. Maori and Pacific patients had poorer metabolic control than their European counterparts (9.1% and 9.3% vs 8.1%, p < 0.001) and higher rates of moderate to severe hypoglycaemia (31.1 and 24.8 vs 14.9 events/100 patient-years, p = 0.03). In multiple linear regression analysis, both ethnicity and SES were independently associated with HbA(1c) (p < 0.001). Other factors associated with higher HbA(1c) level were longer duration of diabetes, higher insulin dose, lower BMI z score and less frequent blood glucose monitoring (p < 0.001). CONCLUSIONS/INTERPRETATION: Both ethnicity and SES independently influenced metabolic control in a large, unselected population of children with type 1 diabetes. Irrespective of SES, Maori and Pacific youth with type 1 diabetes were at greater risk of both moderate to severe hypoglycaemia and long-term complications associated with poor metabolic control.  相似文献   
100.
The advent of whole‐exome next‐generation sequencing (WES) has been pivotal for the molecular characterization of Mendelian disease; however, the clinical applicability of WES has remained relatively unexplored. We describe our exploration of WES as a diagnostic tool in a 3½‐year old female patient with a 2‐year history of episodic muscle weakness and paroxysmal dystonia who presented following a previous extensive but unrevealing diagnostic work‐up. WES was performed on the proband and her two parents. Parental exome data was used to filter potential de novo genomic events in the proband and suspected variants were confirmed using di‐deoxy sequencing. WES revealed a de novo non‐synonymous mutation in exon 21 of the calcium channel gene CACNA1S that has been previously reported in a single patient as a rare cause of atypical hypokalemic periodic paralysis. This was unexpected, as the proband's original differential diagnosis had included hypokalemic periodic paralysis, but clinical and laboratory features were equivocal, and standard clinical molecular testing for hypokalemic periodic paralysis and related disorders was negative. This report highlights the potential diagnostic utility of WES in clinical practice, with implications for the approach to similar diagnostic dilemmas in the future.  相似文献   
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