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41.
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
42.
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
43.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
44.
Non-typhoid Salmonella gastroenteritis 总被引:2,自引:0,他引:2
45.
Glick RD Nadler EP Blumgart LH La Quaglia MP 《Journal of pediatric surgery》2000,35(2):303-7; discussion 308
46.
Ewing's sarcoma/primitive neuroectodermal tumor of the ureter: a case report and review of the literature 总被引:5,自引:0,他引:5
Charny CK Glick RD Genega EM Meyers PA Reuter VE La Quaglia MP 《Journal of pediatric surgery》2000,35(9):1356-1358
Extraosseous Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is a rare soft tissue tumor of childhood usually found in the extremities. The authors present the case of a 17-year-old girl who presented with right flank pain and hematuria and during operation was found to have a right ureteral mass. The histopathologic, immunohistochemical, ultrastructural, and cytogenetic characteristics of the excised mass were consistent with extraosseous ES/PNET. This is the first known reported case of extraosseous ES/ PNET of the ureter. The pathologic features and clinical management of this case, as well as a review of the literature, are presented. 相似文献
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The effects of zoledronic acid and dexamethasone on osseointegration of endosseous implants: histological and histomorphometrical evaluation in rats 下载免费PDF全文