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41.
OBJECTIVE: Most neonatologists include an apnea-free period in the criteria for the discharge of preterm infants. However, the length of time one should wait after the cessation of apnea before sending an infant home without a monitor is debated. We undertook this study in an attempt to define a minimal and safe observation period between the time of the last apnea episode and discharge. METHODS: We reasoned that in infants with idiopathic apnea of prematurity, the intervals between days on which apnea occurs gradually increase until some point at which clinically significant apnea ceases. Therefore, knowledge about the intervals between days on which apnea occurred just before the last apnea would provide a reasonable estimate of the minimal safe observation interval between the last apnea and discharge. We reviewed the charts of 266 infants born in 1993 and 1994 at =32 weeks' gestational age or weighing =1500 g at birth from two institutions to determine the intervals between the day on which the last apnea occurred and the previous two days on which apnea occurred. One hundred seventy-five infants were excluded because they never experienced apnea, or data about the last apnea was missing, or they were on xanthines during the period encompassing the last 3 apnea days, or they weighed <1500 g or were <34 weeks' postmenstrual age at the time of the last apnea. Of the 91 remaining infants, gestational age at birth, birth weight, 1- and 5-minute Apgar scores, and discharge weight were not different between the two institutions. For each infant we determined the longest of the intervals between the 2 days on which apnea occurred previous to the day of the last apnea (MAXINT for maximum interval). The infants were then ordered by MAXINT and, starting at the longest MAXINT, the medical records of each infant were carefully examined for other conditions known to be associated with apnea (eg, recovering from anesthesia, sepsis, chronic lung disease, and so forth). The minimal safe observation period was then defined as the longest MAXINT in which there was at least 1 infant with no other explanation for the apnea other than prematurity. RESULTS: The median duration of the intervals between the 2 days on which apnea occurred previous to the day on which the last apnea occurred were 3. 0 and 2.0 days and the median duration of the MAXINT was 4.0 days. On careful examination of the charts, it was determined that each of 13 infants with a MAXINT preceding the day on which the last apnea occurred of greater than 8 days had some other condition that might result in apnea, including residual lung disease, sepsis, surgery, and so forth. In contrast, among the group of infants with a MAXINT of =8 days, at least 1 infant at each MAXINT (eg, 1 to 8) had significant apnea with no other explanation other than prematurity. CONCLUSIONS: We conclude that otherwise healthy preterm infants continue to have apneas separated by as many as 8 days before the last apnea before discharge. Conversely, infants with longer apnea intervals often have identifiable risk factors other than apnea of prematurity. 相似文献
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Antiparkinsonian actions of ifenprodil in the MPTP-lesioned marmoset model of Parkinson's disease 总被引:2,自引:0,他引:2
Nash JE Fox SH Henry B Hill MP Peggs D McGuire S Maneuf Y Hille C Brotchie JM Crossman AR 《Experimental neurology》2000,165(1):136-142
Dopamine-replacement strategies form the basis of most symptomatic treatments for Parkinson's disease. However, since long-term dopamine-replacement therapies are characterized by many side effects, most notably dyskinesia, the concept of a nondopaminergic therapy for Parkinson's disease has attracted great interest. To date, it has proved difficult to devise a nondopaminergic therapy with efficacy comparable to that of dopamine replacement. In animal models of Parkinson's disease, loss of striatal dopamine leads to enhanced excitation of striatal NR2B-containing NMDA receptors. This is responsible, in part at least, for generating parkinsonian symptoms. Here we demonstrate that, in the MPTP-lesioned marmoset, monotherapy with the NR2B-selective NMDA receptor antagonist, ifenprodil, administered de novo, has antiparkinsonian effects equivalent to those of l-DOPA (administered as its methyl ester form). In MPTP-lesioned marmosets, median mobility scores, following vehicle-treatment were 12.5/h (range 6-21), compared to 61/h (range 26-121) in normal, non-MPTP-lesioned animals. Following ifenprodil (10 mg/kg) treatment in MPTP-lesioned marmosets, the median mobility score was 66/h (range 34-93), and following l-DOPA (10 mg/kg i.p.) treatment 89/h (range 82-92). The data support the proposal that NR2B-selective NMDA receptor antagonists have potential as a nondopaminergic monotherapy for the treatment of parkinsonian symptoms when given de novo. 相似文献
44.
Flupirtine ameliorates ischaemic-like death of rat retinal ganglion cells by preventing calcium influx 总被引:4,自引:0,他引:4
The effect of flupirtine on the loss of retinal ganglion cells following transient elevation of intraocular pressure (experimental ischaemia) or NMDA-induced excitotoxicity was studied. Ischaemia (60 min) or intravitreal injection of NMDA (20 nmol) caused a decrease in Thy-1 mRNA and Thy-1 immunoreactivity which are associated with ganglion cells. Administration of flupirtine counteracted these changes. Moreover, flupirtine dose-dependently inhibited NMDA-induced 45Ca(2+) influx into cultured cortical neurones and retinal pieces in vitro with maximal inhibition being observed at 200 microM. A similar concentration of flupirtine failed to inhibit kainate-stimulated calcium influx into cultured cortical neurones. In addition, flupirtine had no significant effect on [3H]nitrendipine or [3H]diltiazem binding to cortical membranes. The present studies are consistent with previous findings which suggested flupirtine to act as a NMDA antagonist by a mechanism that still remains to be clarified. 相似文献
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We report our experience of using latissimus dorsi myocutaneous flaps after failed conservation for breast carcinoma. Twenty-nine patients were treated by two methods of reconstruction. Seventeen patients with central recurrent tumours and three patients with radiation necrosis of the breast were treated by total mastectomy and latissimus dorsi reconstitution with silicone implant. Nine patients underwent latissimus dorsi reconstruction with preservation of the nipple for recurrent peripheral tumours. After a mean follow up period of 20.2 months no local recurrences have been observed but a longer period of follow-up is necessary to evaluate the likely long term recurrence rate. 相似文献
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Michael R. Nash Steven Jay Lynn Scott Stanley David Frauman Judith Rhue 《The International journal of clinical and experimental hypnosis》2013,61(3):224-235
The present study was undertaken to replicate an earlier experiment and to clarify which factors in this previous experiment (Nash, Johnson, & Tipton, 1979) were responsible for the obtained child-like behaviors of hypnotically regressed Ss. As in the previous study, 3 characteristics of the transitional object relationship (spontaneity, specificity, and intensity) were used as the primary criteria to investigate the effects of hypnotic age regression when Ss were regressed to age 3 and placed in 3 home situations. While in the previous study E suggested separation anxiety and isolation during the 3 home situations (mother-absent condition), the present study deleted all references to anxiety and isolation, and replaced them with suggestions of security and maternal proximity (mother-present condition). As expected, the mother-present versus mother-absent conditions led to similar hypnotized-simulating differences. In further accord with predictions, hypnotized Ss and simulating Ss requested a transitional object infrequently in the presence of mother. The importance of using dependent measures which index affective processes germane to interpersonal affect-laden experience is discussed. 相似文献
50.
A summary of 3 papers of special interest to researchers and clinicians that appeared in the general scientific and medical literatures. All are robust, empirically grounded studies, however, each differs in its approach and design. These studies are exemplars of customizing design to the question asked and the opportunities afforded by setting. The first addresses delusions of alien control in the human brain; the second examines mechanisms accounting for the efficacy of hypnosis in the treatment of irritable bowel syndrome; the third is an extraordinarily clever empirically grounded N-of-1 case study tracking the behavioral treatment of a teenager with motor and vocal tics. Taken together, these three studies illustrate the variety of research designs that can be used to bring evidence to bear on important matters of theory and practice. 相似文献