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101.
BACKGROUND: Multiple episodes of rejection following cardiac transplantation have been associated with an increased incidence of coronary atherosclerosis. Total lymphoid irradiation (TLI) has been shown to be a successful treatment for persistent allograft rejection, but its effect on coronary arterial disease has yet to be evaluated. METHODS: From 1987 to 1999, 40 patients required TLI for persistent or recurrent allograft rejection following heart transplantation. Each patient's (Group 1, n = 31) post-transplant coronary angiograms were examined and compared with those of a control group (Group 2, (n = 32) matched for time of transplantation. Degree of coronary stenosis was assessed on a 6-point scale. All patients received induction therapy (rabbit anti-thymocyte globulin or OKT3) and standard triple immunosuppressive therapy. TLI (80 cGy x 10 fractions) was used for the treatment of recurrent or persistent rejection on the basis of clinical indications. Actuarial survival, number and treatment of rejection episodes, and severity of coronary artery disease were compared in each group. RESULTS: Recipient gender, age, race and cytomegalovirus (CMV) status at time of transplant, along with donor gender, CMV status and graft ischemia time, were similar in both groups. Group 1 donor age was younger than that of Group 2 (22.2 +/- 11.2 vs 31.5 +/- 13.6 years, p = 0.004), and the indication for surgery in Group 1 patients was more likely to be ischemic heart disease (15 of 31 vs 6 of 32, p = 0.02). Mean follow-up was 5.7 +/- 3.5 years in Group 1 vs 6.9 +/- 3.8 in Group 2 (p = NS). Group 1 had more rejection episodes (4.4 +/- 2.2 vs 2.3 +/- 2.0, p = 0.0002) and more steroid treatments (9.78 +/- 4.0 g vs 5.14 +/- 4.7 g, p < 0.0001), but less coronary artery disease compared with Group 2 (p = 0.035). CONCLUSIONS: Despite multiple episodes of rejection, patients treated with TLI after cardiac transplant appear to develop less coronary atherosclerosis than appropriately matched controls.  相似文献   
102.
103.
Summary. Very low birthweight (VLBW) is a commonly used endpoint in perinatal epidemiology, but the population of VLBW infants comprises a wide range of gestational ages and rates of fetal growth. We used data from a population-based study of all 1072 black and white VLBW liveborn infants born in 29 counties in Georgia between April 1986 and March 1988. Less than 1% of the VLBW infants were ≥ 37 weeks gestation; most were 29–32 weeks (26%) or 25 to 28 weeks (40%); 12% were 22 weeks or less. All infants 33 weeks gestation or greater were growth retarded. The population of VLBW infants seems to comprise three groups: approximately 11% very immature infants of 22 weeks or less; the majority of infants, born between 23 and 30 weeks, 90% of which are of normal weight for their gestational age; and a group of less premature, growth-retarded infants from 31 to 36 weeks. We found little or no difference in the distribution of gestational age or the percentage of intrauterine growth rates (IUGR) between black and white infants. In the USA the VLBW rate among black infants is over three times greater than that among white infants and consequently the rates of the three types of VLBW among black infants are likely to be triple those among white infants.  相似文献   
104.
Back pain among nurses is a common problem. Prior studies of this problem have been based on cross-sectional or retrospective data. This 18-month prospective study involving nurses newly graduated from nursing school investigated personal, worksite, and training factors associated with future risk of back pain. Each nurse underwent a preliminary interview and periodic follow-ups to identify those with back injuries. Contingency tables and logistic regression analyses demonstrated that prior significant back pain episodes (evidenced by previous job changes because of back pain, frequent medication use, etc.) were associated with increased future risk. Training at nursing school or on the job did not have a protective effect. This pilot study therefore suggests factors useful in placement and counseling of new nurses and indicates the need for further implementation of mechanical lift assist device use. © 1994 Wiley-Liss, Inc.  相似文献   
105.
Background. A single deep inspiration (DI) is known to be a potent bronchodilator but it is not known if repeated DI can accelerate sustained recovery from bronchoconstriction. Methods. We induced sustained bronchoconstriction using increasing concentrations of nebulized methacholine (Mch) during tidal breathing and assessed airway narrowing by measuring respiratory resistance (Rrs) using forced oscillation in six healthy subjects. On separate days we examined the effects of DI every 3 minutes and of prohibition of DI on recovery of Rrs for 30 minutes after the end of Mch nebulization. Results. Bronchoconstriction (Rrs ∼ 150% above baseline) was induced. DI during recovery had a transient bronchodilator effect but no cumulative effect. At 30 minutes after end of nebulization (and 2 minutes after the last DI) Rrs was 87% above baseline compared to 93% above baseline when DI was prohibited. Conclusion. Recovery from induced bronchoconstriction with methacholine was slow (∼ 2%/min) and not accelerated by frequent DI.  相似文献   
106.
107.
The Annual Scientific Meeting of the Australian Association of Neurologists includes a Grand Rounds Session in which unusual cases are presented. The Chairmen of the 2006 session, Drs Richard Stark and Heather Waddy, lead the audience through a discussion of the history, physical signs, diagnostic investigations and finally the diagnosis at intervals throughout the case presentation. In introducing the cases Dr. Stark emphasized that the cases were selected because they were unusual and the final diagnosis may not be evident at the outset. The approach to the clinical problems and the process of thinking through the differential diagnoses and the method of investigation were as important to the discussion of these cases as the final diagnosis itself. These cases are reported here including an edited summary of the discussion with the same emphasis on the method of clinical analysis and the diagnostic process.  相似文献   
108.
Neuropsychiatric symptoms are common in older adults with dementia and can be associated with a rapid decline in cognitive and functional status. This article reviews the current literature supporting the use of atypical antipsychotic medications in this population. Among the currently available atypical antipsychotics, risperidone and olanzapine have been the most widely studied in double-blind, randomized, placebo-controlled clinical trials. Despite the common use of other atypical antipsychotic medications, their efficacy and safety in older adults with dementia has not been as extensively studied. Some controversy surrounds the use of atypical antipsychotic agents in older adults with the suggestion that they may increase the incidence of stroke or even death. Despite the potential for increased risk of harm from the use of these medications, atypical antipsychotics are often effective in treating troublesome neuropsychiatric symptoms refractory to other treatments. Whenever possible, these atypical antipsychotic drug treatments should be combined with non-pharmacological treatments to limit the need and dose of antipsychotic drugs and constant monitoring for potential harms should be maintained. The choice of which atypical antipsychotic agent can be guided by the nature and severity of the target symptom and the medication least likely to cause harm to the patient.  相似文献   
109.
Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design. It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both hippocampal and prefrontal brain regions that are crucially involved in memory processing. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
110.
Coeliac disease has been associated with a variety of neurological conditions, most frequently cerebellar ataxia and peripheral neuropathy. To date, chorea has not been associated with coeliac disease. We present the case histories of 4 individuals with coeliac disease and chorea (4 women, average age of onset of chorea 61 years). Unexpectedly, most of these patients showed a notable improvement in their motor symptoms after the introduction of a gluten-free diet.  相似文献   
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