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BackgroundTelemonitoring, the use of communication technology to monitor clinical status, is gaining attention as a strategy to improve the care of patients with heart failure. A system of frequent monitoring could alert clinicians to early heart failure decompensation, providing the opportunity for intervention before patients become severely ill and require hospitalization. Moreover, patients' participation in a daily monitoring program could have a favorable effect on their health behaviors. The literature on telemonitoring for heart failure, however, is quite limited.Methods and MaterialsTelemonitoring to Improve Heart Failure Outcomes (Tele-HF) is a randomized, controlled, trial designed to compare an automated, daily symptom, and self-reported weight monitoring intervention with usual care in reducing (all-cause) hospital readmissions and mortality among patients recently hospitalized with decompensated heart failure. The intervention will be implemented and all outcomes will be assessed over a 6-month period. The purpose of the intervention is to collect information about symptoms, clinical status and weight and to engage participants in their own self-care. Participants are recruited from general cardiology, heart failure specialty, and primary care practices across the United States.ConclusionsThe results of this study may inform future policy decisions regarding implementation of telemonitoring in treatment of heart failure.  相似文献   
23.
BackgroundTelemonitoring, the use of communication technology to remotely monitor health status, is an appealing strategy for improving disease management.Methods and ResultsWe searched Medline databases, bibliographies, and spoke with experts to review the evidence on telemonitoring in heart failure patients. Interventions included: telephone-based symptom monitoring (n = 5), automated monitoring of signs and symptoms (n = 1), and automated physiologic monitoring (n = 1). Two studies directly compared effectiveness of 2 or more forms of telemonitoring. Study quality and intervention type varied considerably. Six studies suggested reduction in all-cause and heart failure hospitalizations (14% to 55% and 29% to 43%, respectively) or mortality (40% to 56%) with telemonitoring. Of the 3 negative studies, 2 enrolled low-risk patients and patients with access to high quality care, whereas 1 enrolled a very high-risk Hispanic population. Studies comparing forms of telemonitoring demonstrated similar effectiveness. However, intervention costs were higher with more complex programs ($8383 per patient per year) versus less complex programs ($1695 per patient per year).ConclusionThe evidence base for telemonitoring in heart failure is currently quite limited. Based on the available data, telemonitoring may be an effective strategy for disease management in high-risk heart failure patients.  相似文献   
24.
Mutations in the chloroquine resistance (CQR) transporter gene of Plasmodium falciparum (Pfcrt; chromosome 7) play a key role in CQR, while mutations in the multidrug resistance gene (Pfmdr1; chromosome 5) play a significant role in the parasite's resistance to a variety of antimalarials and also modulate CQR. To compare patterns of genetic variation at Pfcrt and Pfmdr1 loci, we investigated 460 blood samples from P. falciparum-infected patients from four Asian, three African, and three South American countries, analyzing microsatellite (MS) loci flanking Pfcrt (five loci [approximately 40 kb]) and Pfmdr1 (either two loci [approximately 5 kb] or four loci [approximately 10 kb]). CQR Pfmdr1 allele-associated MS haplotypes showed considerably higher genetic diversity and higher levels of subdivision than CQR Pfcrt allele-associated MS haplotypes in both Asian and African parasite populations. However, both Pfcrt and Pfmdr1 MS haplotypes showed similar levels of low diversity in South American parasite populations. Median-joining network analyses showed that the Pfcrt MS haplotypes correlated well with geography and CQR Pfcrt alleles, whereas there was no distinct Pfmdr1 MS haplotype that correlated with geography and/or CQR Pfmdr1 alleles. Furthermore, multiple independent origins of CQR Pfmdr1 alleles in Asia and Africa were inferred. These results suggest that variation at Pfcrt and Pfmdr1 loci in both Asian and African parasite populations is generated and/or maintained via substantially different mechanisms. Since Pfmdr1 mutations may be associated with resistance to artemisinin combination therapies that are replacing CQ, particularly in Africa, it is important to determine if, and how, the genetic characteristics of this locus change over time.  相似文献   
25.
We studied effects of monoclonal antibodies on lymphocyte subpopulations in patients with allergic rhinitis treated with histamine2 antagonists. The OKT4/OKT8 ratio after treatment showed a statistically significant decrease compared with initial values, the expression of a relative increase in the OKT8 subpopulation containing the suppressor fraction. In control patients no significant variations were observed. These results confirm our hypothesis that histamine2 antagonists act in allergic rhinitis by modulating the activity of T-suppressor lymphocytes reduced in atopic patients.  相似文献   
26.

Purpose

To develop a patient-reported outcome instrument for measuring anemia symptoms and their impact in patients with chemotherapy-induced anemia (CIA).

Methods

Qualitative research was conducted using six focus groups and 24 interviews with 46 CIA patients, eight interviews in patients receiving chemotherapy with no CIA history and two interviews in patients successfully treated for CIA. Atlas.ti 5.0 was used to organize key concepts. Cognitive interviews with 16 CIA patients and assessment of relevance of each item to CIA by 10 clinicians were also conducted to evaluate content validity.

Results

Most CIA patients were white (76%) and female (83%), and the average age was 60?years. The most common cancer types were breast cancer (54%) and lung cancer (17%). Tiredness was the most prevalent symptom and rated as the most important by 83% of CIA patients; weakness, shortness of breath, lightheadedness, and dizziness were ranked next in importance. The final anemia impact measure (AIM) contains: (1) daily CIA symptom diary (9 items), and (2) impact of CIA-related tiredness (29 items covering daily living activities, social activities, cognitive function, and emotions). Cognitive interviews found that the AIM was relevant and easy to understand.

Conclusions

The AIM assesses important patient-perceived CIA symptoms and their impact and was developed using extensive patient qualitative data.  相似文献   
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Blastomyces dermatitidis is a dimorphic fungus endemic to northwestern Ontario, Manitoba and some parts of the United States. The fungus is also endemic to parts of Africa. Pulmonary and extrapulmonary findings of a 24-year-old African man who presented with weight loss, dry cough and chronic pneumonia not resolving with antibiotic treatment are presented. The unusual occurrence of pulmonary blastomycosis associated with skin lesions and a moderate pleural effusion is reported.  相似文献   
29.
Redistribution thallium-201 imaging 2 to 4 h after exercise may be incomplete and therefore may be inadequate to fully assess myocardial variability. Late redistribution imaging 24 h after exercise has been proposed to overcome this limitation of thallium stress imaging. However, because of poor count density the image quality on these studies is often suboptimal. In the present study the diagnostic information on 24-h planar thallium redistribution images was compared with that on images obtained after a reinjection of thallium at rest. Eighty-four patients with a stress thallium-201 defect had delayed redistribution imaging after 2 to 4 h and 24 h later, and again after an injection of thallium at rest. Defect reversibility on 24-h redistribution images was compared quantitatively with that on images after injection of thallium at rest. The quality of thallium images at rest was consistently better than that of 24-h redistribution images. Poor quality studies occurred in 13% of 24-h redistribution images compared with 0.4% of the studies at rest. Significantly more defect reversibility was detected on images after the reinjection at rest. Of 41 patients who appeared to have a fixed defect at 2- to 4-h redistribution imaging, 11 (27%) had a reversible defect by 24-h redistribution imaging compared with 29 (71%) after thallium-201 reinjection. No clinical variables at the time of stress testing were predictive of late defect reversibility. It is concluded that in patients with fixed a thallium defect at 2 to 4 h after exercise, reimaging after a reinjection at rest provides better diagnostic information than does 24-h late redistribution imaging.  相似文献   
30.
BACKGROUND & AIMS: Constitutive expression of cyclooxygenase 2 (COX-2) has been found in 85% of colorectal cancers. Ras mutations are found in 50% of colorectal adenocarcinomas. The aim of this study was to determine the role of COX-2 in ras-induced transformation in rat intestinal epithelial (RIE) cells. METHODS: Cell growth was determined by cell counts. The expression of COX-2 was examined by Northern and Western analyses. For tumorigenicity assays, cells were inoculated into dorsal subcutaneous tissue of athymic nude mice. DNA-fragmentation assays were performed to detect apoptosis. RESULTS: The expression of COX-2 was increased in RIE-Ras cells at both messenger RNA (9-fold) and protein (12-fold) levels. Prostaglandin I2 levels were elevated 2.15-fold in RIE-Ras cells. Serum deprivation further increased COX-2 expression 3.8-fold in RIE-Ras cells. Treatment with a selective COX-2 antagonist (SC58125) inhibited the growth of RIE-Ras cells through inhibition of cell proliferation and by induction of apoptosis. SC-58125 treatment reduced the colony formation in Matrigel by 83.0%. Intraperitoneal administration of SC-58125 suppressed RIE-Ras tumor growth in nude mice by 60.3% in 4 weeks. SC-58125 treatment also induced apoptosis in RIE-Ras cells as indicated by increased DNA fragmentation. CONCLUSIONS: Overexpression of COX-2 may contribute to tumorigenicity of ras-transformed intestinal epithelial cells. Selective inhibition of COX-2 activity inhibits growth of ras-transformed intestinal epithelial cells and induces apoptosis. (Gastroenterology 1997 Dec;113(6):1883-91)  相似文献   
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