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Heather J. Zar Michael J. Asmus Eugene G. Weinberg 《Pediatric allergy and immunology》2002,13(3):217-222
Inhaled therapy using a metered‐dose inhaler (MDI) with attached spacer has been increasingly recognized as the optimal method for delivering asthma medication for acute attacks and chronic prophylaxis. However, in developing countries the cost and availability of commercially produced spacers limit the use of MDI‐spacer delivery systems. A 500‐ml plastic bottle has been recently adapted to function as a spacer. This article reviews the current data on the efficacy of this bottle‐spacer and discusses its advantages and limitations. It is concluded that a modified 500‐ml plastic bottle is an effective spacer; modification and use of this device should be incorporated into international guidelines for the management of children with asthma. 相似文献
75.
Lukas Foggensteiner Julia Baylis Heather Moss Paul Williams 《Peritoneal dialysis international》2002,22(4):471-476
OBJECTIVE: To establish the effectiveness and patient acceptability of initiating peritoneal dialysis (PD) according to published guidelines. SETTING: A university teaching hospital and a neighboring district general hospital. DESIGN: Nonrandomized prospective pilot study. PATIENTS: 39 patients with a Kt/V > 2.0 attending predialysis clinics at both hospitals agreed to participate in this study. METHODS: Patients were started on a single exchange of dialysate overnight. Dialysis adequacy was monitored at least every 2 months and incremental increases in dialysis were used to maintain combined urinary and dialysis Kt/V above 2.0. Routine laboratory parameters and complications of dialysis were monitored during the follow-up period. RESULTS: The mean weekly Kt/V at initiation of dialysis was 2.09. Median actuarial survival on a single exchange before requiring incremental dialysis was 297 days. At the end of the study period, all patients were still alive: 8 remained on 1 exchange, 18 were on more than 1 exchange, 8 had switched to hemodialysis, and 5 had received renal transplants. During the 12,665 patient-days on single-exchange dialysis, there were 14 hospital admissions of 12 patients. This resulted in a mean of 1.64 hospital days per patient-year for the whole group. During the follow-up period there were 2 episodes of bacterial peritonitis, 3 pleural leaks, 1 patent processus vaginalis, and 1 inguinal hernia that required surgical intervention. The use single daily icodextrin exchanges was associated with a 46% incidence of culture-negative peritonitis. CONCLUSIONS: This pilot study has shown that a timely start of dialysis with a single overnight PD exchange is acceptable to patients. Incremental dialysis as residual renal function falls is easily managed and patients also find this acceptable. Complication and hospitalization rates were low. The presence of residual renal function often allows complications to be managed without the need for hemodialysis. The use of icodextrin as a single-exchange dialysate is associated with sterile peritonitis in a significant proportion of cases. 相似文献
76.
Prognosis of Childhood Seizure Disorders: Present and Future 总被引:2,自引:2,他引:0
Fritz E. Dreifuss 《Epilepsia》1994,35(S2):S30-S34
Summary: The prognoses for seizure disorders have been examined since the beginnings of epileptology, and only recently has the realization emerged that, ultimately, prognosis depends on causation, which, in turn, determines whether a condition is self-limited or progressive. This factor is more important than either mode or alacrity of therapeutic intervention. The epilepsies are a series of conditions that have the final common path of either increasing cerebral irritability or synchronizing normally occurring electrical activity in such a manner that seizures result. In turn, some seizure disorders are characterized by secondary changes in neuronal synaptogenesis, leading to the development of circuits of predilection, which then render the process autonomous. Epilepto-genesis has then become epilepsy, which is the norm in acquired rather than genetic epileptogenesis. An understanding of the basic differences between the primary (idiopathic) epilepsies and the secondary (acquired or symptomatic) epilepsies is basic to a discussion concerning prognosis and to the development of a definitive individualized treatment plan. An elucidation of the genetic factors in idiopathic epilepsy and their neurochemical consequences represents a major frontier in epileptology. 相似文献
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Peter M Miller Ruth Stockdell Lynne Nemeth Chris Feifer Ruth G Jenkins Paul J Nietert Andrea Wessell Heather Liszka Steven Ornstein 《Substance Abuse》2006,27(1-2):61-70
Many medical conditions are caused or exacerbated by heavy drinking, necessitating alcohol screening and discussion in primary care practices. This is particularly true of hypertension, the most common primary diagnosis in the United States, which has been linked to the regular consumption of 3 or more standard alcoholic beverages a day. The Accelerating Alcohol Screening-Translating Research into Practice (AA-TRIP) project was designed to improve detection and management of alcohol problems in primary care patients with hypertension. Medical providers are being trained using the Practice Partner Research Network's- Translating Research into Practice (PPRNet-TRIP) quality improvement model. This includes a multi-method intervention (electronic medical records, on-site academic detailing, practice feedback reports and annual network meetings) to help practices increase adherence to clinical guidelines. Qualitative analyses of initial steps taken by nine primary care practices toward the routine implementation of alcohol screening guidelines are presented. Organizational factors and provider and patient characteristics all influenced the method and consistency of alcohol screening and intervention. Perceived time constraints, patient sensitivity to questions about alcohol, and possible stigma associated with a diagnosis of alcoholism were also relevant barriers requiring problem solving. 相似文献
79.
Human xenoreactive natural antibodies of the IgM isotype activate pig endothelial cells 总被引:1,自引:0,他引:1
Abstract: Preformed, xenoreactive natural antibodies (XNA) and complement (C) are involved in the initiation of vascular rejection of organs transplanted between discordant species, presumably by stimulating donor organ endothelial cells (EC). Although C is known to play a role in the activation of EC, it has not been clear whether the antibodies serve only to anchor the initial components of C, and thus permit the C cascade to proceed, or whether the antibodies themselves deliver a signal to the EC. We have tested affinity-purified human IgM containing XNA (IgM-XNA) for its ability to stimulate in vitro the up-regulation of genes in pig EC. Northern blot analysis shows that IgM, which contains XNA, stimulates mRNA accumulation for certain genes (including IL-8, PAI-1, and ECI-7, a new gene that we have found is associated with EC activation), but not others known to be up-regulated in response to TNF, IL-1 or LPS. Our results show that XNA provide a signal to EC, and thus may themselves participate in activation of EC and consequent vascular rejection. 相似文献
80.
Zusammenfassung Bei der Messung der thermischen Ausdehnung von ungedehnten oder nur wenig gedehnten tierischen Geweben mit Faserstruktur machte sich bisher die thermische Änderung des Auftriebes der Versuchsobjekte in der sie umgebendenRinger-Lösung störend bemerkbar. Um diesen Auftriebsfehler auszuschalten und somit auch an ungedehnten Geweben quantitative Versuche über thermische Ausdehnung anstellen zu können, wurde das optische Lineardilatometer vonWöhlisch dadurch verbessert, daß die Versuchsobjekte durch eine an dem festen Dilatometerarm angebrachte Quarzplatte unterstützt wurden. Die Auswirkung der scheinbaren Gewichtsänderungen auf den Dilatometerzeiger wird hierdurch aufgehoben. Eine Störung des Versuches durch die Platte findet infolge der außerordentlich geringen thermischen Ausdehnung des Quarzes nicht statt.Mit dieser Apparatur wurden erstmalig Versuche zur direkten Bestimmung der thermischen Ausdehnung der Herzmuskulatur vorgenommen. Als Versuchsobjekt dienten Streifenpräparate aus dem Ventrikel von R. esculenta. Die Versuche wurden in einem weiten Bereiche der Dehnungen (0% bis über 50%) angestellt. Es ergab sich eine weitgehende Übereinstimmung im Verhalten des Herzmuskels und des Skeletmuskels: Im Bereiche kleiner Dehnungen ist der lineare thermische Ausdehnungskoeffizient (l. th. A.K.) des erregbaren Herzmuskels negativ; an völlig ungedehnten Streifen ergab sich der Mittelwert =–(3,47±0,78) · 10–5. Durch stärkere Dehnung kommt es wie beim Skeletmuskel und beim Nackenband zu einem Umschlagen des l. th. A.K. zu positiven Werten. Beim toten Herzmuskel ist derl. th. A.K. stets positiv.D 20. 相似文献