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71.
Matilde Valencia-Flores David N. Velázquez-Martínez Julían E. Villarreal 《Psychopharmacology》1990,102(1):136-144
The chronic exposure of rats to a schedule of operant water reinforcement coupled with chronically restricted access to water sensitized the animals to intermittentd-amphetamine injections (0.31–2.5 mg/kg with intervals of 12–23 days between any two injections) in such a way that this drug came to produce catastrophic losses of body weight (32.4% of control levels). In the sessions whend-amphetamine was administered, the rats were also given a total of 12 brief electric shocks. Loss of body weight was unaccompanied by parallel changes in operant behavior performance, or in food or water intake. Remarkably, in other studies with the same interventions (sham schedule sessions, water deprivation, and foot shocks), with the exception that reinforcers were never delivered,d-amphetamine did not produce catastrophic falls in body weight. This super-reactivity tod-amphetamine toxicity may be mediated by a possible stressor action of the schedule of reinforcement. Its mechanism might be analogous to the known sensitization produced by classical experimental stressor stimuli to the repeated administration ofd-amphetamine. 相似文献
72.
Milena G. J. Jahoda Helen Brandenburg Titia Cohen-Overbeek Frans J. Los Eva S. Sachs Juriy W. Wladimiroff 《American journal of medical genetics. Part A》1993,46(5):483-485
Data from 4,300 consecutive cases following prenatal diagnosis by transcervical (TC) CVS (n = (1,570) and transabdominal (TA) CVS (n = 2,370) were evaluated. In the follow-up study only infants examined by a physician were included. Gestational age varied between 8.5 and 11.6 weeks (mean 10.3 weeks) for TC-CVS and between 9.3 and 20 weeks (mean 12.3 weeks) for TA-CVS 98% of TC-CVS was performed at 9–10 weeks, 80.7% of TA-CVS procedures were carried out at 12–15 weeks. Selective termination took place in 97 cases of TC-CVS (6.1%) and in 72 cases of TA-CVS (2.6%). Another 8 Women had a termination for psychosocial reasons, resulting in 4,123 (1,469 TC, 2,645 TA) continuing pregnancies. The overall fetal loss rare <28 weeks was 5.4% (n = 80) for TC-CVS and 2.6% (n = 70) for TA-CVS. The overall incidence of congenital abnormalities after birth was 0.9%. Two terminal transversal limb defects were detected in the TC-CVS group (0.14%) against one (0.04%) in the TA-CVS group. © 1993 Wiley-Liss, Inc. 相似文献
73.
EPF单克隆抗体杂交瘤细胞株的建立 总被引:1,自引:0,他引:1
本文用纯化的早孕因子免疫BALB/C小鼠,通过鼠-鼠杂交瘤技术,成功地建立了2株分泌EPF单克隆抗体的杂交瘤细胞。经检测,它们所分泌的抗体亚类均为IgG1,毁交瘤染色体数目100-106条,EISA检测诱生腹水抗体效价为1:1.28*10^5,连续培养生物学性状稳定。抗EPF抗原的单克隆抗体的建立,为深入研究EPF的生物学性质、特征提供了有力的工具。 相似文献
74.
肺表面活性物质治疗新生儿胎粪吸入综合征的临床研究 总被引:4,自引:0,他引:4
目的探讨肺表面活性物质(PS)治疗新生儿胎粪吸入综合征(MAS)的有效性及临床价值。方法采用气管内滴入PS治疗8例MAS患儿,其中6例接受PS2剂,2例接受PS3剂。结果给予首剂PS后10分钟患儿青紫迅速消失,皮肤转红润,经皮测定血氧饱和度(TcSaO2)升高。30分钟后患儿低氧血症迅速改善,动脉血氧分压、动脉血氧分压与吸入氧浓度比值、动脉肺泡血氧分压比值、呼吸机有效指数较治疗前显著增高,分别由原来的528±098kPa、866±352kPa、012±006kPa及014±006ml·kPa-1·kg-1增加到891±143kPa、1681±418kPa、021±005kPa及026±007ml·kPa-1·kg-1;而吸入氧浓度及平均气道压逐渐降低,由原来的068±019kPa及220±042kPa降低到053±008kPa及193±048kPa。重复应用PS后亦有相似效果。结论PS能有效地改善MAS患儿肺顺应性及氧合功能。重复应用PS可巩固和加强疗效。 相似文献
75.
Early laparoscopic cholecystectomy for acute cholecystitis 总被引:4,自引:0,他引:4
Background: The timing of laparoscopic cholecystectomy for acute cholecystitis remains controversial.
Methods: One hundred ninety-four patients with acute cholecystitis were reviewed. The conversion rates for the various number of days
of symptoms before surgery were analyzed. The conversion rate dramatically increased from 3.6% for those patients with 4 days
of symptoms to 26% for those patients with 5 days of symptoms. The mean number of days of symptoms prior to surgery in those
patients who underwent successful laparoscopic cholecystectomy was 4.1 as compared to 8.0 in those patients who required open
cholecystectomy (p < 0.0001). Based on this data the patients were divided into two groups. Group 1 consisted of 109 patients who underwent
laparoscopic cholecystectomy within 4 days of onset of symptoms and group 2 consisted of 85 patients who underwent laparoscopic
cholecystectomy after more than 4 days following onset of symptoms.
Results: The conversion rate from laparoscopic to open cholecystectomy was 15%. The conversion rate for group 1 was 1.8% as compared
to 31.7% for group 2 (p < 0.0001). Indications for conversion were inability to identify the anatomy secondary to inflammatory adhesions (68%), cholecystoduodenal
fistula (18%), and bleeding (14%). The major complication rate for group 1 was 2.7% as compared to 13% for group 2 (p= 0.007). The mortality rate for all patients with attempted laparoscopic cholecystectomy for acute cholecystitis was 1.5%.
The average procedure time for group 1 was 100 ± 37 min vs 120 ± 55 min in group 2. The average number of postoperative hospital
days in group 1 was 5.5 ± 2.7 days as compared to 10.8 ± 2.7 days in group 2.
Conclusions: We advocate early laparoscopic cholecystectomy within 4 days of onset of symptoms to decrease major complications and conversion
rates. This decreased conversion rate results in decreased length of procedure and hospital stay.
Received: 28 March 1996/Accepted: 12 September 1996 相似文献
76.
Outcome Following Bariatric Surgery in Super versus Morbidly Obese Patients: Does Weight Matter? 总被引:4,自引:2,他引:2
Mark Bloomston MD Emmanuel E Zervos MD Mario A Camps MD Sarah E Goode RN Alexander S Rosemurgy MD 《Obesity surgery》1997,7(5):414-419
Background: Numerous investigators have attempted to identify prognostic indicators for successful outcome following bariatric
surgery. The purpose of this study was to determine whether degree of obesity affects outcome in super obese [>225% ideal
body weight (IBW)] versus morbidly obese patients (160-225% IBW) undergoing gastric restrictive/bypass procedures. Methods:
Since 1984, 157 patients underwent either gastric bypass or vertical banded gastroplasty. Super obese (78) and morbidly obese
(79) patients were followed prospectively, documenting outcome and complications. Results: Super obese patients reached maximum
weight loss 3 years following bariatric surgery, exhibiting a decrease in body mass index (BMI) from 61 to 39 kg/m2 and an average loss of 42% excess body weight (EBW). Morbidly obese patients had a decrease in BMI from 44 to 31 kg/m2 and carried 39% EBW at 1 year. After their respective nadirs, each group began to regain the lost weight with the super obese
exhibiting a current BMI of 45 kg/m2 (61% EBW) versus 34 kg/m2 (52% EBW) in the morbidly obese at 72 months cumulative follow-up. Currently, loss of 50% or more of EBW occurred in 53%
of super obese patients versus 72% of morbidly obese (P < 0.01). Twenty-six percent of super obese patients returned to within 50% of ideal body weight (IBW) while 71% of morbidly
obese were able to reach this goal (P < 0.01). Co-morbidities and complications related to surgery were similar in each group. Conclusions: Super obese patients
have a greater absolute weight loss after bariatric surgery than do morbidly obese patients. Using commonly utilized measures
of success based on weight, morbidly obese patients tend to have better outcomes following bariatric surgery. 相似文献
77.
Elizabeth Landerholm 《Early child development and care》1994,101(1):13-22
The computer use of two classrooms of kindergarten aged children in private school in Chicago were compared for variance in terms of the age and sex of the children, for variance by classroom, and for variance in the software selected. The major statistical method used was analysis of variance. There were two dependent variables: total frequency of computer use and the difference between the frequency in the first half and that in the second half (in order to examine the changing pattern of computer use in the two classrooms). There was no significant difference in computer use by sex or age, but there was a significant difference in the frequency of computer by classroom in the second half of the project compared to the first half. There was no significant difference in the software selected. 相似文献
78.
Summary Histological, ultrastructural and morphometrical observations on Clarke's column were carried out in 18 patients with sporadic amyotrophic lateral sclerosis (ALS) and 15 age-matched control subjects. Of the 18 ALS patients 6 had been on a respirator before death. Bunina bodies were found in the neuronal cytoplasm in 7 of the 12 non-respirator-supported ALS patients and in 3 of the 6 respirator-supported patients. The number of spheroids was significantly higher in the non-respirator-supported patients (P<0.01) than in the control subjects; however, the number in the respirator-supported patients was about equal to that in the controls. The number of neurons in Clarke's column in the non-respirator-supported ALS patients was not reduced, but in the respirator-supported patients they tended to disappear with time after respiratory support. These findings suggest that Clarke's column neurons are also involved primarily in the disease process in sporadic ALS. However, they may begin to disappear only after the patients require respiratory support.Supported in part by a research grant for CNS degenerative diseases from the Ministry of Health and Welfare, Japan 相似文献
79.
本文对从事京剧打击乐的55人(110耳)进行了听力调查及动态观察。利用图表进行对比分析,发现110耳中高频听力损伤89耳,占81%;语频听力损伤32耳,占29.1%;其中伴有高频耳鸣78耳,占70.9%。动态观察30人(60耳),均为永久性听阈阈移。高频听力损伤最早出现的频率是4kHz,并见典型“V”谷,符合噪声性聋的诊断。 相似文献
80.