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51.
OBJECTIVES: To compare preference assessments that were made by using the EuroQol EQ-5D and the Health Utilities Index Mark II. SUBJECTS: 561 patients in a randomized trial of tirilazad mesylate for aneurysmal subarachnoid hemorrhage. MEASURES: Three preference assessments (a value score for the EuroQol instrument and value and utility scores for the Health Utilities Index) made three months after randomization. The averages for each of the three scores, stratified by clinical outcomes and attributes of the Health Utilities Index health status classification system, were compared. To evaluate potential sources of difference between the instruments, the authors estimated two alternative Health Utilities Index scoring rules that were based on patient responses to the EuroQol instrument. RESULTS: Patients' ratings of their current health made by using the 100-point visual analog scale from the EuroQol instrument were more similar to the utility scores for the Health Utilities Index than they were to the value scores for the Health Utilities Index. The biggest differences between the visual analog scores for the EuroQol instrument and the utility scores for the Health Utilities index were seen at higher levels of functioning. CONCLUSION: For states representing higher levels of functioning, differences were seen between patients' self-ratings obtained by using the EuroQol instrument and the patients' utility scores on the Health Utilities Index; for states representing lower levels of functioning, substantial agreement was observed between these two scores. Differences observed at the higher levels of functioning suggest that further research is needed to determine whether the Health Utility Index's assignment of a score of 1.0 to the reference state representing being healthy is appropriate. 相似文献
52.
Rationale: Results of single-dose studies suggest that the effects of pretreatment with the putative anti-addictive compound, ibogaine,
on drug-induced locomotor behavior depends on the previous drug history of the animal. Objectives: To compare the effects of ibogaine pretreatment on the dose-locomotor response function for cocaine in rats treated chronically
with either saline or cocaine. Methods: Rats were chronically treated with either cocaine (15 mg/kg, IP, once daily for 5 days, followed by 2 week withdrawal) or
saline. Ibogaine (40 mg/kg, IP) or vehicle was administered and 19 h later, a cocaine dose-locomotor response test was conducted
(0, 5, 10, 20 and 40 mg/kg, IP). Results: Chronic cocaine administration augmented the locomotor response to cocaine in chronic cocaine-treated rats, compared to
acutely treated controls. Ibogaine pretreatment enhanced the locomotor effects of cocaine in both chronic and acute cocaine
groups. Furthermore, due to the shape of the dose-response curve, in chronic cocaine but not in acute cocaine rats, ibogaine
pretreatment enhanced the locomotor response to 5 and 10 mg/kg cocaine while decreasing the locomotor response to 40 mg/kg
cocaine. Conclusions: These data demonstrate definitively that ibogaine can enhance sensitivity to the locomotor stimulant effects of cocaine,
an effect which depends, in part, on the previous cocaine history of the animal.
Received: 19 December 1998 / Final version: 2 March 1999 相似文献
53.
The main objective of this study was to elicit proportional cause specific mortality in the underfives in the urban slums
of Lucknow in North India. The families with under five mortality in the 28 randomly selected slums in 1993 were located from
the records of the slum health workers and verbal autopsy was conducted to assign a cause of death.
There were 71 deaths among 2796 children. The annual under five mortality was 25.4 and the under five mortality rate was 126.7.
After the neonatal period, “high fever” that could not be classified into any other disease incorporated in the verbal autopsy
instrument, was the most common symptom associated with death, seen in 21.1% cases (95% C.I.: 15.5–34.4%) followed by these
diseases: pheumonia in 19.7%, diarrhea in 18.3% and measles in 11.4%.
“High fever” as the leading symptom associated with death is being reported for the first time from the urban slums of India.
There is an urgent need to identify the underlying etiologies of death due to “high fever” and the policy implications are
that children with fever must receive immediate and continued medical attention till the symptom persists. 相似文献
54.
MJ McKinley RM McAllen GL Pennington A. Smardencas RS Weisinger BJ Oldfield 《Clinical and experimental pharmacology & physiology》1996,23(Z3):99-104
- 1 Autoradiographic binding studies have shown that the AT1 receptor is the predominant angiotensin II (AngII) receptor subtype in the central nervous system (CNS). Major sites of AT1 receptors are the lamina terminalis, hypothalamic paraventricular nucleus, the lateral parabrachial nucleus, rostral and caudal ventrolateral medulla, nucleus of the solitary tract and the intermediolateral cell column of the thoraco-lumbar spinal cord.
- 2 While there are differences between species, AT2 receptors are found mainly in the cerebellum, inferior olive and locus coeruleus of the rat.
- 3 Circulating AngII acts on AT1 receptors in the subfornical organ and organum vasculosum of the lamina terminalis (OVLT) to stimulate neurons that may have a role in initiating water drinking.
- 4 Centrally administered AngII may act on AT1 receptors in the median preoptic nucleus and elsewhere to induce drinking, sodium appetite, a sympathetic vasoconstrictor response and vasopressin secretion.
- 5 Recent evidence shows that centrally administered AT1 antagonists inhibit dipsogenic, natriuretic, pressor and vasopressin secretory responses to intracerebroventricular infusion of hypertonic saline. This suggests that an angiotensinergic neural pathway has a role in osmoregulatory responses.
- 6 Central angiotensinergic pathways which include neural inputs to the rostral ventrolateral medulla may use AT1 receptors and play a role in the function of sympathetic pathways maintaining arterial pressure.
55.
LSD, mescaline, and MDMT (5-methoxy-N,N-dimethyltryptamine) in normal rats induced dose-dependent rotation (circling behavior), which was consistent in direction from week to week (1 week separating hallucinogen administration). The direction of LSD-induced rotation for individual animals was the same as amphetamine-induced, but not apomorphine-induced, rotation. Of the three postsynaptic serotonin antagonists (methysergide, cyproheptadine, and 2-bromo-LSD) tested, only methysergide induced rotation; this rotation was consistent in direction from week to week, and was in the same direction as LSD-induced rotation. l-LSD induced weak rotation and was approximately six times less potent than d-LSD. p-Chlorophenylalanine pretreatment increased the sensitivity to LSD, whereas -methyl-p-tyrosine pretreatment blocked LSD-induced rotation. Simultaneous administration of LSD and amphetamine induced rotation significantly greater than amphetamine alone; a similar effect was observed with LSD plus scopolamine. However, apomorphine plus LSD induced rotation similar in magnitude to apomorphine alone. These results suggest that the mechanism by which hallucinogens induce rotation is consistent with an inhibitory action on the serotonin-containing midbrain raphe neurons. The inhibition of raphe neuronal firing could disinhibit nigrostriatal activity (possibly at the level of the substantia nigra). Methysergide-induced rotation could result from partial antagonism of postsynaptic serotonin receptors in the substantia nigra or striatum. The dopaminergic properties of LSD may attenuate rotation resulting from disinhibition of nigrostriatal activity by interacting with presynaptic nigrostriatal dopamine autoreceptors. 相似文献
56.
Sandra J Horning Edie Weller KyungMann Kim John D Earle Michael J O'Connell Thomas M Habermann John H Glick 《Journal of clinical oncology》2004,22(15):3032-3038
PURPOSE: To compare low-dose (30 Gy) radiotherapy (RT) with observation (OBS) in limited-stage aggressive lymphoma patients achieving complete remission (CR) after chemotherapy, and to measure conversion from partial response (PR) to CR with high-dose (40 Gy) RT. PATIENTS AND METHODS: From 1984 to 1992, stage I (with risk factors) and II adults with diffuse aggressive lymphoma in CR after eight cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) were randomly assigned to 30 Gy involved-field RT or OBS. PR patients received 40 Gy RT. RESULTS: Among 172 CR patients, the 6-year disease-free survival (DFS) was 73% for low-dose RT versus 56% for OBS (two-sided P = .05). Failure-free survival (two-sided P = .06), and time to progression (two-sided P = .06) also favored RT. Intent-to-treat analyses yielded similar results. No survival differences were observed. Three RT versus 15 OBS patients relapsed in initial disease sites. At 6 years, failure-free survival was 63% in PR patients; conversion to CR did not significantly influence clinical outcome. CONCLUSION: For patients in CR after CHOP, low-dose RT prolonged DFS and provided local control, but no survival benefit was observed. The majority of PR patients were event-free at 6 years despite residual radiographic abnormalities. Future efforts should be directed toward improved imaging and more effective systemic therapies. 相似文献
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60.
C KAPPAGODA DN SCHELL RM HANSON & P HUTCHINS 《Journal of paediatrics and child health》1998,34(6):508-512