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51.
Ageno W Steidl L Marchesi C Dentali F Mera V Squizzato A Crowther MA Venco A 《Haematologica》2002,87(3):286-291
BACKGROUND AND OBJECTIVES. Patients with deep vein thrombosis are selected for home treatment on the basis of their clinical and social condition. Cancer is frequently associated with venous thromboembolism and is often considered an exclusion criterion for outpatient treatment. We investigated the impact of cancer on the outpatient management of venous thrombosis. DESIGN AND METHODS. We performed a prospective, cohort study on consecutive patients with objectively documented deep vein thrombosis. All were assessed for home treatment. Hospital admission was recommended in the presence of common exclusion criteria. All patients were treated with low molecular weight heparin and warfarin. Information on previous, active, or suspected cancer was collected. Recurrent thrombosis, bleeding and mortality were documented at a 3-month follow-up. RESULTS. One hundred patients were included; 72 were entirely treated at home (mean age: 61.2 years). There were 22 patients with known cancer: 12 (55%) were managed as outpatients (16.5% of the outpatient population) and 10 were hospitalized (36% of the inpatient population), 6 because of a poor clinical condition, 4 because further investigation of their malignancy was required. The presence of cancer and the likelihood of poor compliance were the most frequent reasons cited for in-hospital treatment. Overall, event rates at 3 months were comparable to those reported in previous studies in the outpatient population and slightly higher in the inpatient population (recurrent thrombosis 1.5% and 7%; bleeding 5.5% and 10.7%; mortality 4% and 18%, respectively). INTERPRETATION AND CONCLUSIONS. Cancer was the most common reason cited for in-hospital treatment. Nevertheless, more than half of the patients with known cancer were safely and effectively treated at home. 相似文献
52.
Stewart MJ Steenkamp V van der Merwe S Zuckerman M Crowther NJ 《Human & experimental toxicology》2002,21(12):643-647
The traditional Zulu remedy impila (Callilepis laureola) can cause acute fatal hepatocellular necrosis, especially in children. We investigated the mechanism(s) of toxicity using HuH-7 hepatocytes. Impila tubers were extracted with boiling water and the aqueous extract was used at different concentrations to study the effects on the morphology of the cells. Flow cytometry and labelling with fluorescent antibodies to tubulin were also used. At high concentrations, necrosis occurred; however, at lower concentrations, the extracts gave rise to a variety of changes including hypercondensation of chromatin, multinucleate cells, nuclear fragmentation and apoptosis. In addition, we observed destruction of cytoplasmic tubulin. These findings give further insight into the mechanism of toxicity of herbal remedies containing atractyloside. 相似文献
53.
Low-intensity warfarin is ineffective for the prevention of PTFE graft failure in patients on hemodialysis: a randomized controlled trial 总被引:3,自引:0,他引:3
Crowther MA Clase CM Margetts PJ Julian J Lambert K Sneath D Nagai R Wilson S Ingram AJ 《Journal of the American Society of Nephrology : JASN》2002,13(9):2331-2337
Polytetrafluoroethylene (PTFE) dialysis grafts in patients with end-stage renal disease (ESRD) are prone to thrombotic failure. The objective of this multicenter, randomized, double-blind, placebo-controlled clinical trial was to determine if warfarin reduces the risk of failure of PTFE dialysis grafts. Patients with ESRD and newly placed PTFE grafts were studied at community and academic dialysis centers in Southwestern Ontario. Patients were allocated to receive warfarin or matching placebo, with the warfarin administered to achieve a target INR of 1.4 to 1.9. Time to graft failure was the main outcome measure. A total of 107 patients (56 allocated to warfarin) were randomized. The time-to-event analysis revealed no significant difference in the likelihood of graft survival between the two groups (odds ratio, 1.76 in favor of placebo; 95% confidence interval, 0.72 to 4.34). Six major bleeds occurred in five patients allocated to warfarin compared with none in the patients who received placebo (P = 0.03). In conclusion, low-dose warfarin was associated with an excess of clinically important major bleeding in patients with ESRD enrolled in this study. Furthermore, low-intensity, monitored-dose warfarin does not appear to prolong PTFE graft survival. 相似文献
54.
背景:曾建议补充抗氧化的维生素以降低先兆子痫风险并减少围生期并发症发生率,但其效果尚不明确。方法:进行一项多中心、随机试验,对孕14—22周的初产妇,每日给予1000mg维生素C及400U维生素E或安慰剂(微晶纤维素)直至分娩。主要观察指标为孕妇先兆子痫风险、新生儿死亡或其他严重结局(根据澳大利亚和新西兰新生儿网的定义),以及分娩的新生儿出生体重低于其孕龄正常体重P10。结果:纳入的1877例妇女中,935例随机分配到维生素组,942例分配到安慰剂组。两组患者的基线特征相似。维生素组与安慰剂组先兆子痫发生风险[6.0% vs 155.0%,RR1.20(95%CI 0.82—1.75)],新生儿死亡或严重不良结局[9.5% vs 12.1%,RR0.79(95%CI 0.61—1.02)]、新生儿出生体重〈正常孕龄体重P10[8.7% vs 9.9%,RR0.87(95%C10.66—1.16)]无显著差异。结论:孕期补充维生素C和维生素E不能降低初产妇先兆子痫风险,也不能降低胎儿宫内生长受限、新生儿死亡和其他新生儿严重并发症发生率。 相似文献
55.
56.
A M Holbrook R Crowther A Lotter C Cheng D King 《Canadian Medical Association journal》2000,162(2):225-233
OBJECTIVE: To systematically review the benefits and risks associated with the use of benzodiazepines to treat insomnia in adults. DATA SOURCES: MEDLINE and the Cochrane Controlled Trials Registry were searched for English-language articles published from 1966 to December 1998 that described randomized controlled trials of benzodiazepines for the treatment of insomnia. Key words included "benzodiazepines" (exploded), "randomized controlled trial" and "insomnia." Bibliographies of relevant articles were reviewed for additional studies and manufacturers of benzodiazepines were asked to submit additional randomized controlled trial reports not in the literature. STUDY SELECTION: Articles were considered for the meta-analysis if they were randomized controlled trials involving patients with insomnia and compared a benzodiazepine with placebo or another active agent. Of the 89 trials originally identified, 45 met our criteria, representing a total of 2672 patients. DATA EXTRACTION: Data were extracted regarding the participants, the setting, details of the intervention, the outcomes (including adverse effects) and the methodologic quality of the studies. DATA SYNTHESIS: The meta-analyses of sleep records indicated that, when compared with placebo, benzodiazepines decreased sleep latency by 4.2 minutes (non-significant; 95% confidence interval (CI -0.7 to 9.2) and significantly increased total sleep duration by 61.8 minutes (95% CI 37.4 to 86.2). Patient-reported outcomes were more optimistic for sleep latency; those randomized to benzodiazepine treatment estimated a sleep latency decrease of 14.3 minutes (95% CI 10.6 to 18.0). Although more patients receiving benzodiazepine treatment reported adverse effects, especially daytime drowsiness and dizziness or light-headedness (common odds ratio 1.8, 95% CI 1.4 to 2.4), dropout rates for the benzodiazepine and placebo groups were similar. Cognitive function decline including memory impairment was reported in several of the studies. Zopiclone was not found to be superior to benzodiazepines on any of the outcome measures examined. INTERPRETATION: The use of benzodiazepines in the treatment of insomnia is associated with an increase in sleep duration, but this is countered by a number of adverse effects. Additional studies evaluating the efficacy of nonpharmacological interventions would be valuable. 相似文献
57.
Evaluation of attempted prevention of unexpected infant death in very high-risk infants by planned health care 总被引:1,自引:0,他引:1
Three hundred and ninety-six babies born in Sheffield between 1982 and 1990 identified as being at "very high risk" of unexpected infant death by means of a scoring system, received an intensive programme of health care including a case discussion between a paediatrician, the GP and the health visitor held in the family doctor's surgery, weekly visits from the health visitor and informal hospital admission. Significantly fewer sudden unexpected infant deaths occurred in this group than were expected by logistic regression anlysis or occurred in the best available control group with comparable scores ( p = 0.024). Problems in evaluation include identification of an adequate control population, ethical difficulties in introducing a controlled study when the programme is already perceived as effective, and the calculation of "expected death rates". The results of this study indicate that very energetic programmes of intervention may prevent some deaths in vulnerable infants. 相似文献
58.
To determine the outcome of congenital lung abnormalities, data were collected retrospectively between January 1991 and December 1996 on any foetus found to have a lung lesion on antenatal ultrasound. A total of 23 foetuses had lung lesions on antenatal ultrasound. In two foetuses the antenatal ultrasound showed bilateral enlarged "bright" echogenic lungs with evidence of hydrops. Both pregnancies were terminated and tracheal atresia was confirmed. In 15 foetuses the antenatal ultrasound appearance was of a unilateral "bright" echogenic lung. There was one case of bronchial atresia and two cases of congenital lobar emphysema, which all had surgery. In nine cases there was a reduction in the size of the lesion on serial antenatal ultrasounds and no lesion was detected after birth. In three cases a small lesion was present after birth on chest radiography. In six foetuses the antenatal ultrasound appearance was of unilateral cystic or mixed cystic and echogenic lung lesions. Two pregnancies were terminated; both had congenital cystic adenomatoid malformation. Four pregnancies were continued and three infants had surgery soon after birth and were confirmed to have had congenital cystic adenomatoid malformation. One infant has been managed conservatively. In conclusion, a definitive diagnosis cannot usually be made antenatally. A large lesion on initial scan does not necessarily predict a poor outcome. The natural history of small asymptomatic postnatal lesions is unknown and a long-term prospective study is needed to determine the outcome of these lesions. 相似文献
59.
Crowther CA Kornman L O'Callaghan S George K Furness M Willson K 《British journal of obstetrics and gynaecology》1999,106(12):1273-1279
OBJECTIVES: To assess the efficacy of an ultrasound scan at the first antenatal visit. DESIGN: Randomised clinical trial. SETTING: Women's and Children's tertiary level hospital, Adelaide, Australia. POPULATION: Six hundred and forty-eight women attending for their first antenatal visit at less than 17 weeks of gestation who had no previous ultrasound scan in the pregnancy, who were expected to give birth at the hospital, and for whom there was no indication for an ultrasound at their first visit. METHODS: Eligible consenting women were enrolled by telephone randomisation into either the ultrasound at first visit group, who had an ultrasound at the time of their first antenatal visit, or the control group in whom no ultrasound assessment was done at their first antenatal visit. Both groups of women completed a questionnaire at the end of the first visit on their feelings towards the pregnancy and anxiety levels. Data were collected on details of any ultrasound assessments, including the 18 to 20 weeks morphology scan, and pregnancy outcome. All primary analyses were on an intention-to-treat basis. MAIN OUTCOME MEASURES: The number of women who needed adjustment in dates of 10 days or more on the basis of their 18 to 20 weeks ultrasound morphology scan, who were booked for their morphology scan at sub-optimal gestations, who had a repeat of their maternal serum screening test, or who felt worried about their pregnancy at the end of the first antenatal visit. RESULTS: Fewer women (9%) in the ultrasound at first visit group needed adjustment of their expected date of delivery as a result of the 18 to 20 week ultrasound, compared with 18% of women in the control group (RR 0.52, 95% CI 0.34-0.79; P = 0.002). The number of women who had the 18 to 20 week ultrasound assessment timed suboptimally was similar to that in the control group (16% vs. 21%), as was the number of women who had a repeat blood sample taken for maternal serum screening (6% vs. 6%). Fewer women in the ultrasound at first visit group reported feeling worried about their pregnancy (RR 0.80, 95% CI 0.65-0.99; P = 0.04) or not feeling relaxed about their pregnancy (RR 0.73, 95% CI 0.56-0.96; P = 0.02), compared with women in the control group. CONCLUSIONS: A routine ultrasound assessment for dating offered to women at the first antenatal visit provides more precise estimates of gestational age and reduces the need to adjust the estimate of the date of delivery in mid-gestation. Women who had an ultrasound at the first visit reported more positive feelings about their pregnancy, compared with women in the control group at that time. 相似文献
60.
W F Short G Moss J C Crowther R C Friedman R L Horwitz L G Manco P R Silk 《Gastrointestinal radiology》1985,10(1):85-88
The double-contrast enema's potential for high accuracy depends in part on consistently good inflation of the colon. However, optimal inflation is often not obtained because of deflation during filming, underinflation because of fear of perforating the colon, or patient discomfort. To help meet the dual requirements of ensuring consistently good bowel inflation while avoiding over-inflation, we have designed a modified insufflator which incorporates a manometer and allows accurate readings of intraluminal large-bowel pressures during or following insufflation. In more than 3000 examinations using this method we have experienced no complications. 相似文献