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141.
研究了卡尔曼滤波及平滑在滴定分析中的应用,该法对热力学平衡及非平衡(动力学)体系均能适应;特别是对非平衡滴定,当许多其它方法误差较大或无法使用时,卡尔曼滤波法仍可获得正确的结果。已用于苯扎溴铵的硝酸银电位滴定分析与快速测定。  相似文献   
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143.
Aim: We have designed a study with the objective of describing the clinical impact of other viruses different from the respiratory syncytial virus (RSV) in hospitalized infants with bronchiolitis. Methods: A 3 year prospective study was conducted on infants admitted to the Paediatrics Department of the Severo Ochoa Hospital (Spain). We studied the frequency of 16 respiratory viruses. Clinical characteristics of RSV‐only infections were compared with other single agent viral infections. Results: Positive results were confirmed in 275 (86.5%) of the 318 children studied. A single virus was detected in 196 patients and 79 were dual or multiple viral infections. RSV was detected in 61.3% of total bronchiolitis. Rhinovirus (RV) was 17.4% of the identified virus, followed by human bocavirus (HBoV), adenovirus and metapneumovirus (hMPV). Only RV, HBoV and hMPV were significant as single infections. RSV patients were younger than HBoV (p > 0.0001) and hMPV (p = 0.025). Seasonality was clearly different between them. Children with RSV infection needed treatment in the intensive care unit more frequently than others. Conclusions: In hospitalized infants, RSV was the most frequent agent in bronchiolitis in winter, but other viruses were present in 47% of the patients. RV, HBoV and hMPV had a significant proportion of single infections. Clinical characteristics were similar amongst them, but seasonality was clearly different.  相似文献   
144.

Objectives

The aim of the study was to evaluate the impact of different patterns of nonadherence on treatment outcomes in patients with long‐term follow‐up.

Methods

This cohort study included patients who began highly active antiretroviral therapy during 1996–1999, with the last follow‐up in 2007. Adherence was evaluated every 2 months by monitoring of pharmacy refills and by using self‐reports. Patients were considered nonadherent at a specific visit when less than 90% of the prescribed drugs had been taken. Adherence was categorized as follows. (A) Continuous adherence: a patient had to be adherent in all of the evaluations throughout the period of follow‐up. (B) Treatment interruption: drugs were not taken for more than 3 days, for any reason. Treatment failure was defined as viral load >500 HIV‐1 RNA copies/mL or death. Cox proportional risk models were used to calculate adjusted relative hazards (ARHs) of treatment failure.

Results

A total of 540 patients were included in the study, with a median follow‐up of 8.3 years. Only 32.78% of patients achieved and maintained continuous adherence, and 42.78% of patients had treatment interruptions. Noncontinuous adherence [ARH 1.48; 95% confidence interval (CI) 1.02–2.14] and treatment interruptions (ARH 1.39; 95% CI 1.04–1.85) were associated with treatment failure for the overall cohort; however, for patients with more than 3 years of follow‐up, only treatment interruptions were independently associated with treatment failure.

Conclusions

Only one‐third of patients managed to achieve continuous adherence, and almost half of the patients had treatment interruptions, which have a particularly marked effect on treatment outcomes over the long term.
  相似文献   
145.
Background Heart failure (HF) is a physically and socially debilitating disease that carries the burden of hospital re-admission and mortality. As an aging society, Hong Kong urgently needs to find ways to reduce the hospital readmission of HF patients. This study evaluates the effects of a nurse-led HF clinic on the hospital readmission and mortality rates among older HF patients in Hong Kong. Methods This study is a retrospective data analysis that compares HF patient in a nurse-led HF clinic in Hong Kong compared with HF patients who did not attend the clinic. The nurses of this clinic provide education on lifestyle modification and symptom monitoring, as well as titrate the medications and measure biochemical markers by following established protocols. This analysis used the socio-demographic and clinical data of HF patients who were aged ≥ 65 years old and stayed in the clinic over a six-month period. Results The data of a total of 78 HF patients were included in this data analysis. The mean age of the patients was 77.38 ± 6.80 years. Approximately half of the HF patients were male (51.3%), almost half were smokers (46.2%), and the majority received ≤ six years of formal education. Most of the HF patients (87.2%) belonged to classes II and III of the New York Heart Association Functional Classification, with a mean ejection fraction of 47.15 ± 20.31 mL. The HF patients who attended the clinic (n = 38, 75.13 ± 5.89 yrs) were significantly younger than those who did not attend the clinic (n = 40, 79.53 ± 6.96 yrs) (P = 0.04), and had lower recorded blood pressure. No other statistically significant difference existed between the socio-demographic and clinical characteristics of the two groups. The HF patients who did not attend the nurse-led HF clinic demonstrated a significantly higher risk of hospital readmission [odd ratio (OR): 7.40; P < 0.01] than those who attended after adjusting for the effect of age and blood pressure. In addition, HF patients who attended the clinic had lower mortality (n = 4) than those who did not attend (n = 14). However, such a difference did not reach statistical significance when the effects of age and blood pressure were adjusted. A significant reduction in systolic blood pressure [F (2, 94) = 3.39, P = 0.04] and diastolic blood pressure [F (2, 94) = 8.48, P < 0.01] was observed among the HF patients who attended the clinic during the six-month period. Conclusions The finding of this study suggests the important role of nurse-led HF clinics in reducing healthcare burden and improving patient outcomes among HF patients in Hong Kong.  相似文献   
146.
Iloprost (ILO) is employed intravenously for the treatment of severe Raynaud phenomenon (RP) and digital ulcers (DU) in systemic sclerosis (SSc). The aim of this study was to evaluate the safety and tolerability of the intravenous treatment with ILO in different phases of SSc. Eighty-one consecutive non-selected SSc patients, all on nifedipine, with moderate RP, treated with ILO infusion, were retrospectively evaluated. Patients were sub classified according to the edematous or fibrotic/atrophic cutaneous phase of the disease. ILO was infused with a progressive increase of the dosage up to the achievement of patient’s tolerance, 1 day/week. In cases of slower infusion regimen due to adverse events (AE) at the beginning of the administration, patients received a lower dose of the drug (not possible to quantify precisely the final cumulative dosage). 16/81 SSc patients presented digital edema, 5 developed diarrhea, and 9 developed transient hypotension during the infusion at 20 ml/h that ameliorated when the drug was withdrawn. Moreover, 10/16 edematous patients experienced significant and painful digital swelling, unlike patients in the fibrotic group (p?<?0.0001); 11/16 patients reported flushing and 7/16 headache, always controlled with dose tapering below 10 ml/h. In the atrophic/fibrotic phase patients (65/81), 10 developed diarrhea and 24 hypotension at infusion rate of 20 ml/h that led to temporary withdrawal of the drug. When ILO was restarted and kept below 10 ml/h, no side effects were experienced. 23/65 patients experienced flushing and 8/65 headache, all controlled with infusion reduction below 10 ml/h. In these patients, adverse events were significantly less frequent than in the edematous group (p?=?0.023 and p?=?0.008, respectively). Our data suggest that calcium channel blockers should be transitorily stopped while using ILO and that a pre-treatment approach might reduce or control adverse events. In patients with digital edema, ILO infusion should be carefully employed after the evaluation of patient’s drug tolerance.  相似文献   
147.
148.
A molecular genetics-based epidemiological investigation was carried out in 1997 in the territory of North-West Tuscany, central Italy, to calculate incidence and prevalence rates of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). Results were compared with a previous epidemiological study conducted in the same area in 1981, in the pre-dystrophin era. Routine adoption of methods of molecular diagnosis determined an increase in prevalence of BMD from 1.06 x 10(-5) to 2.42 x 10(-5) inhabitants, while cumulative incidence of DMD was markedly decreased from 23.12 x 10(-5) during the period 1965-1976 to 10.71 x 10(-5) male live births during the period 1977 1994. The combined reduction of DMD/BMD diagnostic error rate and familial recurrence could explain these results, providing the bases for a consistent redefinition of dystrophinopathy carrier frequency in the area considered.  相似文献   
149.
Natural and human-caused disasters, violence with weapons, and terrorist acts have touched directly the lives of thousands of families with children in the United States.1 Media coverage of disasters has brought images of floods, hurricanes, and airplane crashes into the living rooms of most American families, with limited censorship for vulnerable young children. Therefore, children may be exposed to disastrous events in ways that previous generations never or rarely experienced. Pediatricians should serve as important resources to the community in preparing for disasters, as well as acting in its behalf during and after such events.  相似文献   
150.
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