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71.
OBJECTIVE: To evaluate the prognostic roles of prolonged signal-averaged P wave duration (SAPWD), raised levels of natriuretic peptides, and clinical characteristics in patients with stable congestive heart failure (CHF). DESIGN: The SAPWD was assessed from a signal-averaged electrocardiogram (SAECG), and the plasma levels of N-terminal pro-atrial natriuretic peptide (Nt-proANP) and N-terminal pro-brain natriuretic peptide (Nt-proBNP) were measured in 43 consecutive patients with stable CHF without prior supraventricular arrhythmia. Echocardiographic and clinical data were also recorded. Time to death, hospitalization due to deteriorated CHF, or ECG-documented atrial fibrillation (AF) was recorded over a 438-day median follow-up. RESULTS: During follow-up, 17 patients met an endpoint defined as death, AF, or hospitalization due to deteriorated CHF. Proportional hazard regression including the variables high age, prolonged SAPWD, raised levels of Nt-proANP and Nt-proBNP, and low ejection fraction (EF) showed that only prolonged SAPWD > or =149 ms was associated with an increased risk of meeting an early endpoint; the hazard ratio 3.94 with 95% confidence interval 1.50-10.42; p = 0.006. CONCLUSION: Prolonged SAPWD appears to predict early death, AF development, or hospitalization due to deterioration of CHF in patients with stable CHF.  相似文献   
72.
Aase O 《Cardiology》1999,92(2):128-134
A decision support computer program (DSP) was used by the emergency room physician as a diagnostic tool on patients admitted with acute chest pain to guide the referral of these patients either to the Coronary Care Unit (CCU) or general ward. The DSP used Bayes' theorem on 38 anamnestic and clinical variables to classify patients into one of nine diagnoses. During a six months trial period 32 physicians used the DSP to diagnose 493 patients admitted with acute chest pain. The physicians referred the patients to CCU or general ward based on their clinical judgements, the ECG findings and the diagnostic estimates given by the DSP. The program correctly diagnosed 150 (84%) of 178 patients with acute myocardial infarction and 63 of 112 patients with unstable angina. However, acute ischemic heart disease (acute myocardial infarction or unstable angina) was correctly classified by the DSP for 259 (89%) of 290 patients. By using the DSP, the number of patients unnecessarily referred to CCU was reduced from 35% to 19% and the number of patients in need of CCU observation misallocated to general ward was reduced from 13% to 10%. Thus, use of the DSP in the emergency room on easily available anamnestic and clinical variables may improve referrals to the CCU, optimize therapy and resource use.  相似文献   
73.
A meta-analysis and several studies of patients with grade III and IV gliomas have indicated that the addition of nitrosurea based chemotherapy to surgery and radiation may improve survival. We performed a phase II study of pre-irradiative chemotherapy with BCNU, cisplatin and etoposide. This implies a short total treatment duration and a reliable response evaluation.The treatment schedule was three cycles of BCNU 200mg/m2 i.v. on day 1, cisplatin 20mg/m2 i.v. on day 1–5 and etoposide (VP-16) 100mg/m2 i.v. on day 1–5, given every five weeks and followed by localized radiation, 60Gy in 30 fractions. Twenty-nine patients with newly diagnosed glioblastoma multiforme (GBM), mean age 50 (27–66) and performance status (PS) 0–2 were included.Using the Macdonald criteria 33% had partial remission (PR), 41% stable disease (SD) and 26% progressive disease (PD) after chemotherapy. After additional radiation 44% had PR, 37% SD and 19% PD. Non-hematological toxicity and leukopenia was mild, but thrombocytopenia (TP) frequent. Grade III and IV TP occurred in 25% and 57% respectively, and grade III bleeding in 45%. No severe or fatal complications was seen. Median time to progression (TTP) was 7.6 months (6.0–9.1) and median survival was 11.4 months (10.1–12.7).We conclude that this regimen is effective and feasible in patients with GBM. The short course pre-irradiatory chemotherapy may be less cumbersome than adjuvant chemotherapy and the regimen may be even more active in grade III gliomas.  相似文献   
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Expression of drug-resistant forms of dihydrofolate reductase (DHFR) in hematopoietic cells confers substantial resistance of animals to antifolate administration. In this study, we tested whether the chemoprotection conferred by expression of the tyrosine-22 variant DHFR could be used for more effective therapy of the 32Dp210 murine model of chronic myeloid leukemia (CML). 32Dp210 tumor cells were found to be sensitive to methotrexate (MTX) in vitro, whereas cells expressing the tyrosine-22 DHFR gene were protected from MTX at up to micromolar concentrations. MTX administered at low dose (2 mg/kg/day) did not protect normal C3H-He/J mice from 32Dp210 tumor infused intravenously, with drug toxicity limiting the administration of higher doses. Animals engrafted with transgenic tyrosine-22 DHFR marrow were protected from greater MTX doses (up to 6 mg/kg/day). However, the increased doses of MTX afforded by drug-resistance gene expression surprisingly resulted in decreased survival of the transplanted tumor-bearing animals, with increased levels of tumor detected in peripheral blood. This apparent exacerbation of tumor progression by MTX was not observed in DHFR transgenic mice in which all cells and tissues contain the drug-resistance gene. This suggests that increased tumor progression in MTX-administered animals resulted from MTX sensitivity of a nonhematopoietic host component, thus allowing tumor expansion. We conclude that MTX exacerbates tumor progression in the 32Dp210 model of CML, and that based on this model alternate DHFR inhibitors combined with drug-resistant DHFR or other chemotherapeutic agent/drug-resistance gene combinations may be required for the application of drug-resistance gene expression to the treatment of CML.  相似文献   
76.
OBJECTIVE: To elicit from individuals in a population their current weight and height, weight goals, and weight control strategies to aid in design of effective interventions to prevent and treat obesity. SUBJECTS AND METHODS: By random digit dial telephone survey, 1224 adult residents of Olmsted County, Minnesota, were contacted between February 28 and May 5, 2000. They self-reported weights and weight goals and described physical characteristics associated with their desire to lose weight. RESULTS: Among the 1224 respondents, 65.6% of men and 47.9% of women reported that they were overweight (body mass index [BMI], 25.0-29.9 kg/m2) or obese (BMI, > or =30.0 kg/m2). Only 0.4% of men and 3.7% of women reported that they were underweight (BMI, <18.5 kg/m2). Of the respondents 72.6% of men and 85.1% of women reported that they were either trying to lose or not gain weight. The average weight loss goal for individuals trying to lose weight was 23.4 pounds for men and 28.0 pounds for women. Only one third of individuals trying to lose weight and one fifth of individuals trying not to gain weight reported using the recommended approach of combining energy restriction with at least 150 minutes of exercise per week. CONCLUSIONS: The prevalence of overweight and obesity in the population and the underutilization of combining both restricting energy intake and exercising at least 150 minutes per week for weight control is high. Like the majority of people in the United States, the majority of people in Olmsted County desire to control their weight. The community has responded with plans to help residents meet their goals, although efficacy and outcomes remain to be determined.  相似文献   
77.
Abstract

Objective: To describe experiences among general practitioners (GPs) in Norway regarding horizontal task shifting experiences associated with adverse events that potentially put patient safety at risk.

Design and contributors: We conducted a qualitative study with data from a retrospective convenience sample of consecutive, already posted comments in a restricted Facebook group for GPs in Norway. The sample consisted of 43 unique posts from 38 contributors (23 women and 15 men), presenting thick and specific accounts of potentially adverse events in the context of horizontal task shifting. Analysis was conducted with systematic text condensation, a method for thematic cross-case analysis.

Results: Contributing GPs reported several types of adverse events associated with horizontal task shifting that could put patient safety at risk. They described how spill-over work dispatched to GPs may generate administrative hassle and hazardous delay of necessary examinations. Overdiagnosis, reduced access and endangered accountability occur when time-consuming procedures and pre-investigation before referral are pushed upon GPs. Resource-draining chores beyond GPs’ proficiency is also dispatched without appropriate instruction or equipment. Furthermore, potential malpractice is imposed by hospital colleagues who overrule the GPs’ medical judgement.

Implications: Patient safety is endangered when horizontal task shifting is initiated and performed without a systematic process involving all stakeholders that considers available resources. A risk and vulnerability analysis, securing competent staff, resources, time and equipment before launching such reforms is necessary to protect patient safety. Infrastructure comprised of local coordination groups may facilitate dialogue between health care service levels and negotiate responsibilities and workload.
  • Key points
  • Task shifting between different levels of health care is a relevant and legitimate strategy for planning and policy.

  • GPs in Norway report adverse events related to task shifting from specialist colleagues without proper resource allocation.

  • Patient safety may be put at risk by hazardous delay, overdiagnosis, endangered accountability and potential malpractice.

  • Planning and implementation of task shifting must involve all system levels and relevant stakeholders to ensure patient safety.

  相似文献   
78.
79.
80.
Sporadic inclusion body myositis (sIBM) is a systemic disease that is characterized by substantial skeletal muscle weakness and muscle inflammation, leading to impaired physical function. The objective was to investigate the effect of low‐load resistance exercise with concurrent partial blood flow restriction to the working muscles (blood‐flow‐restricted (BFR) training) in a patient with sIBM. The training consisted of 12 weeks of lower extremity BFR training with low training loads (~25‐RM). The patient was tested for mechanical muscle function and functional capacity before and after 6 and 12 weeks of training. Maximal horizontal gait speed increased by 19%, which was accompanied by 38–92% improvements in mechanical muscle function (maximal isometric strength, rate of force development and muscle power). In conclusion, BFR training was well tolerated by the patient with sIBM and led to substantial improvements in mechanical muscle function and gait speed.  相似文献   
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