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31.
Reduction by delayed hypothermia of cerebral infarction following middle cerebral artery occlusion in the rat: a time-course study. 总被引:8,自引:0,他引:8
The effect of hypothermia on neuronal injury following permanent middle cerebral artery (MCA) occlusion in the rat was examined. Moderate hypothermia (body temperature 24 degrees C) was induced before MCA occlusion (0-minute delay group) in six rats, at 30 minutes in eight rats, and at 1 (seven rats), 2 (seven rats), and 3 (nine rats) hours after occlusion. The rats were kept at a 24 degrees C body temperature for 1 hour, then allowed to rewarm over 90 minutes. The animals were sacrificed 24 hours after MCA occlusion, and infarction was visualized by staining of coronal sections with 2,3,5-triphenyltetrazolium chloride. Infarct volumes were compared to matched normothermic control rats (body temperature 36 degrees C). Additional groups of 0-minute delay hypothermic (10 rats) and control animals (nine rats) were sacrificed 72 hours after MCA occlusion to examine the effects of prolonged survival. A significant reduction in the percentage of infarcted right hemisphere was seen in the animals sacrificed after 24 hours with 0-minute, 30-minute, and 1-hour delays in inducing hypothermia (mean +/- standard error of the mean: 2.2% +/- 0.7%, 4.4% +/- 0.9%, and 3.6% +/- 1.1%, respectively) as compared to normothermic control rats (10.8% +/- 1.5%, p less than 0.01 by Student's t-test). In the 2- and 3-hour delay groups, the percentage of infarcted right hemisphere was 17.1% +/- 2.4% and 12.0% +/- 2.7%, respectively, and no decrease in infarct volume was observed. The 0-minute delay hypothermia group sacrificed after 72 hours also displayed a significant reduction in right hemisphere infarct compared to their respective controls (4.8% vs. 11.7%, p less than 0.05). These findings indicate that, in the setting of permanent MCA occlusion, hypothermia markedly decreases brain injury even when its induction is delayed for up to 1 hour after the onset of ischemia. Ischemic damage does not appear to be merely retarded but permanently averted. 相似文献
32.
Background
The Shoulder Pain and Disability Index (SPADI) is a self-report measure developed to evaluate patients with shoulder pathology. While some validation has been conducted, broader analyses are indicated. This study determined aspects of cross-sectional and longitudinal validity of the SPADI. 相似文献33.
BACKGROUND: Suprasphincteric fistulae remain the most difficult to cure. OBJECTIVES: The purpose of this study was to evaluate the healing rate of suprasphincteric anal fistula treated by ano-cutaneous advancement flap repair, and the impact of this procedure on continence and quality of life. METHOD: Sixteen patients with complex, recurrent or chronic suprasphincteric fistulae associated with significant tissue damage (necrotizing fasciitis, keyhole deformity and anal stenosis) or who had failed previous surgical procedures were treated by ano-cutaneous flap closure. They were assessed pre and postoperatively by the treating surgeon for wound healing and fistula recurrence and later followed up by phone interview using the St Mark's Hospital incontinence score and the Perianal Disease Activity Index (PDAI) as indicators of treatment outcome. RESULTS: Fifteen patients had successful healing of their fistula with the cutaneous flap, with recurrence in only one. The most common short-term complications were minor graft site wound separation, which healed in all cases without intervention, and wound pain, which settled over time and was not associated with recurrence. Continence improved for almost 70% of the patients, with a significant reduction in St Mark's incontinence scores (t = 2.62, 15 d.f., P = 0.02). PDAI also decreased significantly (t = 7.55, 15 d.f., P < 0.001), demonstrating improvement in quality of life for most patients. CONCLUSION: Ano-cutaneous flap can achieve healing of complex and recurrent suprasphincteric anal fistula in patients who had previously failed at other forms of treatment thus improving their quality of life and continence. 相似文献
34.
A. Ben-Arie S. Perlman† Y. Hazan† L. A. Solomon C. Edwards & A. L. Kaplan 《International journal of gynecological cancer》2004,14(5):927-930
OBJECTIVE: The aim of this study was to evaluate a different prevalence and clinical pattern of high-risk endometrial cancer in an indigent population of young women. METHODS: Charts of 71 consecutive patients, treated for endometrial adenocarcinoma during a 6-year period, were reviewed. The patients were divided into two groups contingent upon age--(i) those who were below 40 years and (ii) those who were over 40. Based on histological type, grade, and stage, both groups were subdivided into a low, intermediate, or high-risk cancer category. RESULTS: Of the 13 (18.3%) patients in the younger age group, five patients (38.4%) had high-risk endometrial cancer, compared to only eight patients (13.8%) in the older age group. CONCLUSION: In contradiction to previous reports, our results show that a higher proportion of young indigent women diagnosed with endometrial cancer have a high-risk cancer. Delay in diagnosis can explain only some of the discrepancies in the special clinical pattern of endometrial cancer among this population. Other possible explanations include nutritional differences, genetic susceptibility, immunological status, and high-risk behavior. More epidemiological studies are needed for complete understanding of the unfavorable outcome of endometrial cancer in these young women. 相似文献
35.
Sharon C. Reimold M.D. Sary F. Aranki M.D. Eduardo S. Caguioa M.D. Scott D. Solomon M.D. Vladimir Birjiniuk M.D. Lawrence H. Cohn M.D. Richard T. Lee M.D. 《Journal of cardiac surgery》1994,9(3):304-313
Objectives: The purpose of this study was to determine if a device placed externally around the aortic root decreases regurgitant flow in acute aortic regurgitation. Background: Aortic regurgitant flow is dependent on central aortic pressure and the aortic root and leaflet geometry. It may be possible to decrease aortic regurgitant severity by reducing aortic root size or dimension changes. Methods: Aortic regurgitation was created in eight calf heart specimens suspended in a continuous flow system. Retrograde and antegrade aortic flow and distending aortic pressure were measured at baseline and after placement of an external aortic device at the level of the aortic annulus. In two additional specimens, the incompetent aortic valve was visualized fiberoptically before and after placement of the external device. Acute aortic regurgitation was created surgically in four live calves by excising a portion of the aortic leaflets. Antegrade and retrograde flow, left ventricular pressure, and central aortic pressure were measured at baseline, after creation of aortic regurgitation, and after placement of the external device. Results: In the in vitro calf specimens, regurgitant flow decreased from 46.9 cc/sec to 15.1 cc/sec (66.0%± 21.8% decrease) after placement of the external device (p < 0.001). The regurgitant orifice area decreased from 0.13 ± 0.04 cm2 to 0.04 ± 0.02 cm2 after device placement (p < 0.001). Antegrade flow was reduced to a smaller extent (20.0%± 19.2% decrease) by the device (p < 0.05). Placement of the device around the aorta resulted in improved coaptation of the leaflets with a marked reduction in defect size by endoscopic visualization. Use of the external aortic device was associated with improvement in aortic regurgitant severity in three of four calves with surgically created aortic regurgitation. Concluslons: In these preliminary studies, acute experimental aortic regurgitant severity is decreased by the use of an external aortic device, probably due to reduction in aortic annular dimension changes and improved aortic leaflet apposition. Further studies are needed to determine the effectiveness of this device in chronic aortic regurgitation. (J Card Surg 1994;9:304–313) 相似文献
36.
A new syndrome with features of the Smith-Lemli-Opitz and Meckel-Gruber syndromes in a sibship with cerebellar defects 总被引:3,自引:0,他引:3
A C Casamassima P Mamunes I M Gladstone S Solomon C Moncure 《American journal of medical genetics》1987,26(2):321-336
The Smith-Lemli-Opitz syndrome (SLOS) and the Meckel syndrome (MS) have been regarded as separate autosomal recessive entities. Recently, overlap of these two syndromes has been discussed. A sibship containing a probable new syndrome with features reminiscent of the SLOS and the MS is presented. The literature is reviewed with regard to the frequency of various malformations in these syndromes. Clinical manifestations and cerebellar abnormalities in these sibs are similar to those described in the Joubert syndrome (JS). These three cases may represent a new syndrome with features in common with SLOS, MS, and JS resulting from the same mutant gene, which exhibits considerable pleiotropy. 相似文献
37.
Phyllis Solomon Ph.D. Diane Evans M.S.S.A. Mary Anne Delaney M.D. 《Community mental health journal》1993,29(4):333-346
A majority of a cohort of 62 children and adolescents who had been hospitalized in a state psychiatric facility was found to have received less restrictive services such as outpatient mental health services prior to their index admission. Also, a number had been involved with the juvenile justice system and almost two-thirds had been placed out-of-home. Ninety percent had at least one prior psychiatric hospitalization. Just over half of the cohort received case management and individual counseling post release. About a third received family counseling, and a few received other types of services. At least a third were rehospitalized within a year of release. Although 90% of the cohort received some type of service post release, a higher proportion of non service receivers were rehospitalized than service receivers. Even those who received services had a high rate of rehospitalization. These findings raise questions as to the appropriateness of service provision during and following hospitalization.This study was funded by a grant from the Office of Program Evaluation and Research, Ohio Department of Mental Health. 相似文献
38.
39.
Libor Velíek† Jana Velíková Yael Ptachewich Shlomo Shinnar‡ Solomon L. Mosh醇 《Epilepsia》1995,36(2):179-185
Summary We determined the effects of the N-methyl-Daspartate (NMDA) receptor blocker MK-801 (0.05, 0.1, and 0.5 mg/kg intraperitoneally, i.p.) and phenytoin (PHT, 5, 10, and 20 mg/kg i.p.) on flurothyl-induced clonic and tonic-clonic seizures in 9-, 1 5, 30-, and 60-day-old male rats. Both agents had seizure-, age-, and dose-specific effects. The highest dose of MK-801 was anticonvulsant against clonic flurothyl-induced seizures only in 9- and 60-day-old rats, but suppressed tonic-clonic seizures in all ages. The lowest dose of MK-801 (0.05 mg/kg) produced significant anticonvulsant effects only in 15 day old rats. PHT did not have any effect on clonic seizures throughout development. Both doses of PHT (10 and 20 mg/kg) were anticonvulsant against tonic-clonic seizures in adult rats but not in any other age group. The results indicate that NMDA receptors play an important role in tonic-clonic flurothyl-induced seizures throughout development (especially in 15-day-old rats) and that the anticonvulsant effects of PHT may vary at different stages of brain development. 相似文献
40.
Age-Specific Effects of Baclofen on Pentylenetetrazol-Induced Seizures in Developing Rats 总被引:1,自引:0,他引:1
Summary: Purpose : To determine whether seizures have age-specific features, we studied the role of γ-aminobutyric acid, (GABAB) transmission in rats of various ages (9, 15, 30, and 60 postnatal days). Methods: We used a GABA, receptor agonist baclofen (2 or 5 mg/kg intraperitoneally, i.p.) and a GABAB receptor antagonist CGP 35348 (100 or 600 mg/kg i.p.) in the pentylenetetrazol (PTZ)-induced model of clonic and tonic-clonic seizures (100 mg/kg subcutaneously, s.c.).
Results : Whereas baclofen was anticonvulsant and CGP 35348 proconvulsant in most animals, there were distinct age-related differences in the effectiveness of these drugs and the antagonist had some anticonvulsant activity in adults. Furthermore, the two drugs acting at GABAB receptors had a different profile of action in clonic seizures as compared with tonic-clonic seizures.
Conclusions : The differences in the age-specific action of the GABAB agonist and antagonist suggest that different GABAB receptor subsets may mediate the drug effects. The results indicate that putative antiepileptic drugs (AEDs) must be tested during development because it may not be possible to extrapolate age-specific anticonvulsant effects from studies in adult animals. 相似文献
Results : Whereas baclofen was anticonvulsant and CGP 35348 proconvulsant in most animals, there were distinct age-related differences in the effectiveness of these drugs and the antagonist had some anticonvulsant activity in adults. Furthermore, the two drugs acting at GABA
Conclusions : The differences in the age-specific action of the GABA