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Wolfgang G Rehwald Michael Salerno Enn-Ling Chen Burkhard Sievers Raymond J Kim Robert M Judd 《Magnetic resonance in medicine》2007,58(1):82-91
To extend the signal longevity of magnetically excited spins in flowing fluids while in a state of global coherent free precession (GCFP), a refocusing radiofrequency (RF) pulse and bipolar gradient waveforms were combined with the GCFP sequence. The data demonstrate that RF refocusing in the presence of flowing blood is possible, but the improvement in signal amplitude depends on the static magnetic field homogeneity along the direction of motion and the displacement of the spins between the excitation and the RF refocusing pulse, as well as displacement during subsequent RF refocusing pulses. The least amount of phase dispersion and thus the longest lasting signal is obtained with the shortest echo spacing where only one line of data is recorded between two RF refocusing pulses. This approach was successfully used in a phantom and in vivo to image fast and slow blood flow. Depending on the experimental conditions, signal persistence is improved significantly compared to playing the same sequence without RF refocusing, but the improvement is limited by the product of blood flow velocity and the time between RF refocusing pulses. 相似文献
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Alcohol and the adolescent trauma population 总被引:4,自引:0,他引:4
B A Hicks J A Morris S M Bass G W Holcomb W W Neblett 《Journal of pediatric surgery》1990,25(9):944-8; discussion 948-9
Trauma is the leading killer of children and adolescents between 1 and 21 years of age. Alcohol-impaired driving represents the single greatest cause of mortality and morbidity of children over the age of 6. We retrospectively reviewed 878 consecutive adolescent (age range, 16 to 20 years) trauma admissions for blood alcohol concentration (BAC). Four hundred sixty-seven patients had BAC drawn, 258 were BAC-negative (group I), 209 (48%) were BAC-positive (group II). The adolescent drinkers were then compared with a group of 748 adult drinkers (group III). Groups I and II differ in sex, age, time of day of the accident, Injury Severity Score, Glasgow Coma Score, and Revised Trauma Score, whereas group II and III differ by type of accident, type of injury, socioeconomic factors (bad debt), time of day of the injury, and BAC. There were no significant differences in TRISS predicted survival, actual survival, nor mean length of stay. We conclude that (1) alcohol is a significant contributor to injury during adolescence, and (2) adolescent drinkers differ from adult drinkers in their habits, demographics, and socioeconomic status. These socioeconomic differences have implications for the access to and cost-effectiveness of interventions. 相似文献
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Efficacy of Bupivacaine Delivered by Wound Catheter for Post-Caesarean Section Analgesia 总被引:4,自引:0,他引:4
David W. J. Mecklem FANZCA Michael D. Humphrey FRACOG FRCOG Ross W. Hicks DipRACOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1995,35(4):416-421
Summary: A prospective, randomized, double-blind trial was conducted to assess contribution to postoperative analgesia of intermittent instillation of 0.25% bupivacaine beneath the rectus sheath in 70 women delivered by lower uterine segment Caesarean section. The operations were performed via a Pfannenstiel incision under spinal anaesthesia. Background intravenous narcotic analgesia was provided with a patient controlled analgesia system (PCAS) using a standard morphine regimen.
Overall (44 hr) mean morphine consumption was significantly greater in the placebo (saline) group compared to the treatment group (84.2 mg versus 63.3 mg. Two tailed t test p<0.001). The most significant intergroup differences in narcotic use were found in the first 4 hours and between 24 and 36 hours after commencing PCAS (Two tailed t test p=0.014 and 0.003 respectively).
Subjective pain scores were assessed with a 10 cm visual analogue scale (VAS). The mean peak VAS score was greater in controls (5.37) than the treatment group (4.25) between 18 and 24 hours postoperatively (Mann-Whitney U=424, p=0.027). There were no intergroup differences in pain scores for any other time period. The overall incidence of nausea was lower in the treatment group compared to the control group (Chi squared with Yates' correction p=0.046) and a lower degree of sedation was seen in those receiving bupivacaine between 4 and 8 hours after commencing PCAS (Mann-Whitney U=427, p=0.028). No differences in other narcotic related side-effects (vomiting and pruritus) were shown between groups.
Regular instillation of 0.25% bupivacaine beneath the rectus sheath of women delivered by Caesarean section reduces their morphine requirements by 25% in the 44 hours after operation, with an associated reduction in both nausea and early sedation. 相似文献
Overall (44 hr) mean morphine consumption was significantly greater in the placebo (saline) group compared to the treatment group (84.2 mg versus 63.3 mg. Two tailed t test p<0.001). The most significant intergroup differences in narcotic use were found in the first 4 hours and between 24 and 36 hours after commencing PCAS (Two tailed t test p=0.014 and 0.003 respectively).
Subjective pain scores were assessed with a 10 cm visual analogue scale (VAS). The mean peak VAS score was greater in controls (5.37) than the treatment group (4.25) between 18 and 24 hours postoperatively (Mann-Whitney U=424, p=0.027). There were no intergroup differences in pain scores for any other time period. The overall incidence of nausea was lower in the treatment group compared to the control group (Chi squared with Yates' correction p=0.046) and a lower degree of sedation was seen in those receiving bupivacaine between 4 and 8 hours after commencing PCAS (Mann-Whitney U=427, p=0.028). No differences in other narcotic related side-effects (vomiting and pruritus) were shown between groups.
Regular instillation of 0.25% bupivacaine beneath the rectus sheath of women delivered by Caesarean section reduces their morphine requirements by 25% in the 44 hours after operation, with an associated reduction in both nausea and early sedation. 相似文献
16.
L L Hicks 《The Journal of rural health》1990,6(4):485-505
The 1980s saw a retrenchment of the ideology that government intervention could solve the problems of inadequate access to health services in rural areas. Increased emphasis was placed on an ideology that promoted deregulation and competitive market solutions. During the 1980s, the gap in the availability of physicians in metropolitan versus nonmetropolitan areas widened. Also during that time period, the gap between metropolitan and nonmetropolitan populations' utilization of physician services widened. In addition, many indicators of the health status of nonmetropolitan residents versus metropolitan residents worsened during the 1980s. As we enter the 1990s, concern about equitable access to needed health care services and for the vulnerability and fragility of rural health systems has resurfaced. A number of national policies and a research agenda to improve accessibility and availability of health services in rural areas are being considered. 相似文献
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H L June P L June K R Domangue L H Hicks G H Lummis M J Lewis 《Pharmacology, biochemistry, and behavior》1992,41(2):455-460
The ability of Ro15-4513, an imidazobenzodiazepine inverse benzodiazepine agonist, to attenuate/block the acquisition of an ethanol (ETOH)-induced conditioned taste aversion (CTA) was investigated in two experiments. Experiment 1 examined the effects of Ro15-4513 (3 mg/kg) on rats' consumption of a novel saccharin solution under a traditional CTA paradigm. Experiment 2 examined the effects of Ro15-4513 (3 mg/kg) on rats' consumption of a novel saccharin solution under a preexposure CTA paradigm. Under the preexposure paradigm, rats were given Ro15-4513 immediately before each of five daily consecutive preexposure treatments prior to the initial conditioning day. To obtain maximal preexposure and unconditioned stimulus effects, a 2-g/kg dose of ETOH (20% v/v) was used in the present study. As previously reported, animals given ETOH following 20-min access to a novel saccharin solution established moderate to strong aversions, with the degree of aversion being directly related to the number of conditioning days. Experiment 1 showed that Ro15-4513 failed to alter the CTA induced by ETOH. Experiment 2 further showed that Ro15-4513 failed to block the preexposure effect exerted on the ETOH-mediated CTA. The results confirm previous reports regarding the failure of Ro15-4513 to disrupt an ETOH-induced CTA. These data are in agreement with a number of behavioral studies demonstrating the failure of Ro15-4513 to antagonize certain actions of ETOH. Moreover, the present study along with a previous report suggests that ETOH-induced CTA's do not appear to be mediated via actions at the GABA-BDZ receptor complex. 相似文献
20.
Significant progress has been made in the 1980s in early-stage vulvovaginal rhabdomyosarcoma, diethylstilbestrol (DES) clear cell adenocarcinoma of the vagina, and unilateral germ cell tumors of the ovary. In an early state of vulvovaginal rhabdomyosarcoma, systemic vincristine, dactinomycin, and cyclophosphamide (VAC) chemotherapy followed by local excision or local radiation results in a high cure rate with retention of future fertility. Similarly, early-stage DES-related adenocarcinoma of the vagina treated by wide local excision and localized vaginal radiation also results in retention of fertility and a high cure rate. Finally, significant progress has been made in unilateral germ cell tumors of the ovary in which surgical treatment by unilateral salpingo-oophorectomy followed by cisplatin, etoposide, and bleomycin results in not only high cure rates and retention of fertility but will probably be standard therapy for all germ cell tumors of the ovary, including dysgerminoma, a disease most frequently treated in the past by radiation therapy with loss of subsequent fertility. 相似文献