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41.
The PFA-100 is a relatively new laboratory instrument, first described in 1995. There have since been numerous studies assessing its utility as a screening tool for platelet dysfunction and/or von Willebrand's disease (VWD). The PFA-100 displays variable sensitivity to different types of platelet disorders, as well as to antiplatelet medication (e.g. aspirin), with similar caveats for monitoring of primary haemostasis-promoting therapies in platelet dysfunction. There is therefore considerable uncertainty regarding its utility within this context, and we have accordingly performed an audit of usage among participants of the Royal College of Pathologists of Australasia Quality Assurance Program. Of 105 laboratories surveyed, 40 responded that they performed platelet function testing, with 26 (65%) further indicating they utilized the PFA-100. We report a wide variety of laboratory usage among these users, including numbers of tests performed [annual median (range) = 270 (15-6000)], sources of requests (clinical sources and localities), testing criteria and follow-up action. Most tests were completed within 4 h of collection, as recommended by the manufacturer, and most tests were performed as a replacement, or as a preliminary screen of platelet function (i.e. classical aggregation). Most abnormal findings, however, were attributed to antiplatelet medication such as aspirin.  相似文献   
42.
Chemoprevention refers to suppression or reversal of the carcinogenic process using pharmacologic or nutritional agents. Colorectal carcinogenesis is a protracted, multistep process that offers opportunities for prevention. Aspirin and selective cyclooxygenase-2 inhibitors (coxibs) have been evaluated for the prevention of sporadic adenoma recurrence. Aspirin was shown to reduce adenoma recurrence rates in patients with prior colorectal neoplasms; however, the optimal dosage remains unclear. Recent studies of coxibs indicate that these agents are effective in reducing sporadic adenoma recurrence, but chronic use can result in serious cardiovascular toxicity. These data underscore the need for chemopreventive agents with acceptable risk-to-benefit ratios. In this regard, nitric-oxide-releasing aspirin shows chemopreventive efficacy in preclinical models and holds promise for reduced toxicity in humans. Furthermore, ongoing chemoprevention trials are evaluating nutritional supplements, such as folic acid and selenium, and results are eagerly awaited.  相似文献   
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Tolerance of ocular iontophoresis in healthy volunteers.   总被引:4,自引:0,他引:4  
To evaluate ocular tolerance, healthy volunteers were iontophoresed transclerally using novel OcuPhor trade mark hydrogel drug delivery applicators filled with balanced salt solution. In this three-period crossover study in 24 male and female subjects, 16 subjects received 0 mA and two of the following DC currents: 0.1, 0.5., 1.0, 2.0, 3.0, or 4.0 mA for 20 min; 6 subjects received 3 mA for 20 min and 1.5 mA for 40 min (both equivalent to 60 mAmin total charge). Safety and tolerance were determined by subjective VAS and objective ophthalmic assessments. Subjects were evaluated before and up to 22 hr after dosing. The applicators were well-tolerated and no clinically significant changes in symptomology or in ophthalmic assessments were seen following exposure to 0-3.0 mA for 20 min or 1.5 mA for 40 min. At 4.0 mA 2 of 4 subjects reported a burning sensation under the applicator during dosing which resolved by 22 hr post-dose; superficial changes in fluorescein staining were observed at 1 hr, but not at 22 hr. The OcuPhor trade mark system has promise for noninvasive drug delivery to the eye.  相似文献   
46.
Goldenhar and cri-du-chat syndromes: a contiguous gene deletion syndrome?   总被引:2,自引:0,他引:2  
We report a full-term male infant born to nonconsanguinous parents who had clinical features of Goldenhar syndrome and cri du chat syndrome. At birth, the infant was noted to have dysmorphic features with bilateral preauricular tags, rotated ears, bilateral epicanthic folds, a left epibulbar lipodermoid, and an accessory left nipple. After he was assessed for feeding difficulty and tachypnea, he was found to have esophageal atresia with tracheoesophageal fistula. In addition, he had a high-pitched, cat-like cry, characteristic of cri-du-chat syndrome. He also failed a hearing test. Chromosomal analysis and fluorescence in situ hybridisation studies showed an unbalanced karyotype with a terminal deletion of the segment p14 on the short arm of chromosome 5, which is consistent with the cri-du-chat locus. The association of Goldenhar syndrome and cri-du-chat syndrome in this patient suggests that the chromosome 5p14 locus may harbor a gene implicated with Goldenhar syndrome.  相似文献   
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There is limited information on the relationship between parental practices that specifically discourage current cigarette smoking and adolescent cessation, and how this relationship varies by age. Among 1629 adolescent smokers, self-reported receipt of parental communication not to smoke was significantly and positively associated with readiness to quit. The strength and significance of this association decreased from early to middle adolescence and was not significant in late adolescence.  相似文献   
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Reduction of transmission of human immunodeficiency virus type 1 (HIV-1) through human milk is needed. Alkyl sulfates such as sodium dodecyl sulfate (SDS) are microbicidal against HIV-1 at low concentrations, have little to no toxicity, and are inexpensive. The authors have reported that treatment of HIV-1-infected human milk with < or = 1% (10 mg/mL) SDS for 10 minutes inactivates cell-free and cell-associated virus. The SDS can be removed with a commercially available resin after treatment without recovery of viral infectivity. In this article, the authors report results of selective biochemical analyses (ie, protein, immunoglobulins, lipids, cells, and electrolytes) of human milk subjected to SDS treatment and removal. The SDS treatment or removal had no significant effects on the milk components studied. Therefore, the use of alkyl sulfate microbicides to treat milk from HIV-1-positive women may be a simple, practical, and nutritionally sound way to prevent or reduce transmission of HIV-1 while still feeding with mother's own milk.  相似文献   
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Hip fractures among elderly people frequently result in permanent disabilities, nursing home placement, and death. The bulk of hip fracture research focuses on elderly women. Within the Veterans Health Administration (VHA), the majority of patients are men. There are no published national reports on hip fractures with large male samples, or on related inpatient mortality among veterans. This retrospective study of 13,546 veterans with hip fracture discharges from 1998-2002 found unadjusted mortality rates are higher in the VHA, compared with the general population. VHA patients tend to be older men in poor health who stay in the hospital longer Increased knowledge about the risks and outcomes associated with hip fractures in men could lead to improved primary and secondary injury-prevention programs. Rehabilitation nurses in acute care can be catalysts in proactively incorporating protective devices, screening for osteoporosis, and initiating lifestyle changes in their plans of care to optimize outcomes for hip fracture patients.  相似文献   
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