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991.
992.
993.

Background:

The rising prevalence of cardiovascular diseases in the population has increased the demand for cardiovascular imaging procedures (specifically echocardiography) in our center.

Aim:

To determine the percentage of appropriate indications for echocardiography.

Materials and Methods:

This was a prospective study conducted over a period of 1 year in the Department of Medicine of a Tertiary Health Care Center. The clinical diagnoses by the referring clinician and the indications (specific reasons for the study) for the echocardiography were consecutively recorded. The age and gender of the patients were also recorded. The indications were given a score of one to nine according to the revised appropriate use criteria of the American College of Cardiology Foundation and the American Society of Echocardiography (ASE). These indications were then classified into appropriate, inappropriate or uncertain based on the score. (1-3)-inappropriate use, (4-6) were derived.

Results:

There were 25 indications, 16 (64%) were appropriate, 6 (24%) were inappropriate and three (12%) were rated as uncertain.

Conclusion:

Sixty-four percent of the indications for echocardiography are appropriate for the procedure. This implies that the criteria for echocardiography are yet to be fully implemented resulting in overutilization of the procedure.  相似文献   
994.
One hundred out-patients treated by multiple insulin injection regimens underwent clinical audit by retrospective analysis of their case-notes. Patients had been on multiple insulin injection therapy (MIIT) for 1.0-4.5 years (median, 3.6 years) and had had diabetes for 2 months-33 years (median, 8.7 years) at the time of starting pen therapy. Median daily insulin dose per patient did not differ significantly following stabilisation on MIIT or at latest follow-up. The median glycated haemoglobin did not change during each of the 4 years of follow-up. During the year prior to commencing MIIT the patients showed no significant alteration in body weight. Patients' weights rose significantly during each subsequent year. Median weight gains were 0.9 kg (P less than 0.005) during the first year, 1.4 kg (P less than 0.005) during the second year, 0.9 kg (P less than 0.05) during the third year and 1.4 kg (P less than 0.05) during year 4. No such weight gain was recorded in a control group of 30 patients matched for age and duration of diabetes and treated by twice daily insulin injections. Multiple insulin injection regimens used over prolonged periods in a routine clinic setting do not alter metabolic control. However, continuing weight gain appears to occur despite similar daily insulin doses.  相似文献   
995.
Natural history of dilated cardiomyopathy in children   总被引:6,自引:0,他引:6  
To assess the natural history and potential risk factors in childhood dilated cardiomyopathy, we investigated 25 patients (ages 9.6 +/- 4.4 years) who presented after they were 2 years old. All patients had symptoms of congestive heart failure and reduced contractility with a dilated left ventricle at presentation. Two factors at presentation were significantly different between patients who died less than 1 year after the presentation (n = 14) and those who survived for more than 1 year (n = 9); cardiothoracic ratio (65.1% +/- 6.8% vs 57.1% +/- 6.1%, p less than 0.01) and left ventricular ejection fraction (31.3% +/- 7.0% vs 40.0% +/- 6.2%, p less than 0.05). Irrespective of intensive medical therapy, dilated cardiomyopathy in children had a poor prognosis; the actuarial survival rate was 41% at 1 year and 20% at 3 years. Other forms of therapy should be considered in the early stages of dilated cardiomyopathy in this high-risk group.  相似文献   
996.

Purpose

Patients with cancer of the lower and middle rectum who are candidates for curative surgery often have negative opinions on definitive colostomy. The purpose of this study is to compare the quality of life (QoL) of patients who undergo standard treatment for rectal cancer with sphincter preservation or definitive colostomy.

Methods

A total of 125 patients with adenocarcinoma of the lower or middle rectum who underwent radical surgery with curative intent with a follow-up ≥?1 year were recruited: 83 patients (group 1) were subjected to low anterior resection and low colorectal or coloanal anastomosis—thus preserving their sphincter—and 42 (group 2) were treated with abdominoperineal resection, followed by terminal definitive colostomy. QoL was assessed with the EORTC QLQ-C30 and QLQ-CR29 questionnaires.

Results

Health and global quality of life were similar between groups; however, patients who underwent definitive colostomy had higher scores on the emotional (p value?=?0.016) and cognitive function scales (p value?=?0.017). Patients with sphincter preservation presented with more symptoms that were related to stool frequency (p value <?0.001), intestinal constipation (p value?=?0.005), fecal incontinence (p value?=?0.001), buttock pain (p value?=?0.023), and nausea and vomiting (p value?=?0.036), whereas patients with permanent colostomy had higher scores for dysuria (p value?=?0.033).

Conclusion

Although global QoL scores did not differ between groups, patients who underwent definitive colostomy had significantly better functional and symptom scale scores, reflecting greater function with fewer symptoms.
  相似文献   
997.
Molecular recognition by the adaptive immune system relies on specific high-affinity antibody receptors that are generated from a restricted set of starting sequences through homologous recombination and somatic mutation. The steroid binding antibody DB3 and the catalytic Diels–Alderase antibody 1E9 derive from the same germ line sequences but exhibit very distinct specificities and functions. However, mutation of only two of the 36 sequence differences in the variable domains, LeuH47Trp and ArgH100Trp, converts 1E9 into a high-affinity steroid receptor with a ligand recognition profile similar to DB3. To understand how these changes switch binding specificity and function, we determined the crystal structures of the 1E9 LeuH47Trp/ArgH100Trp double mutant (1E9dm) as an unliganded Fab at 2.05 Å resolution and in complex with two configurationally distinct steroids at 2.40 and 2.85 Å. Surprisingly, despite the functional mimicry of DB3, 1E9dm employs a distinct steroid binding mechanism. Extensive structural rearrangements occur in the combining site, where residue H47 acts as a specificity switch and H100 adapts to different ligands. Unlike DB3, 1E9dm does not use alternative binding pockets or different sets of hydrogen-bonding interactions to bind configurationally distinct steroids. Rather, the different steroids are inserted more deeply into the 1E9dm combining site, creating more hydrophobic contacts that energetically compensate for the lack of hydrogen bonds. These findings demonstrate how subtle mutations within an existing molecular scaffold can dramatically modulate the function of immune receptors by inducing unanticipated, but compensating, mechanisms of ligand interaction.  相似文献   
998.
999.
BACKGROUND & AIMS: "Academic detailing" is an effective strategy for promoting the use of screening sigmoidoscopy by primary care physicians. The primary objectives of this study were to determine whether the sustained presence of an "outside" university-based gastroenterologist performing on-site screening sigmoidoscopy promoted long-term utilization and whether the provision for on-site sigmoidoscopy was an effective venue for training primary care endoscopists. METHODS: Nine urban community health centers, including 4 intervention and 5 control sites, participated in a nonrandomized controlled trial conducted over 3 years. RESULTS: By the end of year 3, overall self-reported use of screening sigmoidoscopy increased by 61% for the intervention group vs. only 25% for the comparison group (P = 0.001). Ninety-seven percent of those reporting compliance referred 1 or more asymptomatic average-risk patients for screening examinations. Only 2 of 83 (2.4%) eligible providers completed on-site training and continued performing screening examinations independently. The major barriers to participation included lack of interest, lack of time to learn or perform sigmoidoscopy, concerns about technical competence, and lack of need because of on-site availability. CONCLUSIONS: Maintenance of on-site screening sigmoidoscopy services performed by an outside gastroenterologist promotes long-term utilization but fails as venue for training primary care endoscopists. Alternative strategies for expanding capacity are needed.  相似文献   
1000.
STUDY OBJECTIVES: To evaluate the effect of adding zafirlukast or low-dose theophylline to a beclomethasone dipropionate (BDP) extra-fine hydrofluoroalkane aerosol on bronchial hyperresponsiveness as the primary outcome variable. METHODS: Twenty-four patients with mild-to-moderate asthma were studied using a randomized crossover design with the following three treatment blocks: (1) beclomethasone, 100 microg/d, alone for the first 2 weeks followed by 400 microg/d alone for the next 2 weeks; (2) beclomethasone, 100 microg/d, followed by 400 microg/d, with the addition of zafirlukast, 20 mg bid; (3) beclomethasone, 100 microg/d, followed by 400 microg/d, with the addition of theophylline, 200 to 300 mg bid. Measurements were made after 2 and 4 weeks of each treatment and at pretreatment baseline. RESULTS: The mean trough plasma theophylline concentration was 6.7 mg/L, coinciding with the anti-inflammatory target range (ie, 5 to 10 mg/L). The provocative dose of methacholine causing a 20% fall in FEV(1) (as doubling dose difference from baseline) was significantly (p < 0.05) greater with beclomethasone, 100 microg, plus zafirlukast (1.1 doubling dose) but not with beclomethasone, 100 microg, plus theophylline (0.7 doubling dose) compared to beclomethasone, 100 microg alone (0.4 doubling dose), but not compared to beclomethasone, 400 microg alone (1.1 doubling dose). There were also significant (p < 0.05) differences between beclomethasone, 100 microg, plus zafirlukast (but not BDP, 100 microg, plus theophylline) vs beclomethasone, 100 microg, alone in terms of nitric oxide level, midexpiratory phase of forced expiratory flow, and peak expiratory flow. There were no further significant improvements observed with the addition of zafirlukast or theophylline to beclomethasone, 400 microg. CONCLUSIONS: A leukotriene receptor antagonist, but not low-dose theophylline, conferred significant additive anti-inflammatory effects to therapy with a low-dose inhaled corticosteroid but not to that with a medium dose of an inhaled corticosteroid. Thus, optimizing the dose of inhaled corticosteroid as monotherapy would seem to be the logical first step, which is in keeping with current guidelines.  相似文献   
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