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991.
大白鼠56只,共分四组,即①对照组;②电针组;③吗啡组;④吗啡+电针组。应用Sternbergel氏PAP免疫组织化学技术显示各组动物脊髓内P物质(SP),脑啡肽(ENK),及以Karnovsky-Roots氏组织化学方法显示乙酰胆碱酯酶(AChE),此外,还取已染SP及AChE的切片制作电子显微镜标本,作SP及AChE超微分布的观察,各种活性物质,并作了半定量测定及分析。电针后,在痛阈升高的同时,脊髓第Ⅱ层内SP的免疫反应性(LI)升高(P<0.001,与对照组相比),然而,与此相反在同一个部位内的ENK-LI降低(P<0.001)。注射吗啡后,SP-LI与电针组者相似;在第Ⅱ层内坛加(P<0.001),但注射吗啡动物若再进行电针,SP-LI不仅不继续升高反而降低(P<0.001,与吗啡组相比)。至于脊髓后角内AChE活性的组织化学改变,各组动物间互相差异,如:3.855±0.550(对照组),4.225±0.477(电针组),3.252±0.405(吗啡组)以及3.775±0.401(吗啡+电针组)。脊髓第Ⅱ层,不仅富于SP-LI,而且AChE也丰富、电镜观察表明“细”纤维轴终末内SP-LI见于清亮突触囊泡的周围,而由“粗”纤维(有薄层髓鞘者)AChE多分布于轴内。以上结果表明:在SP-LI改变方面,电针镇痛与吗啡镇痛的作用相似,但是在AChE活性的改变方面,二者作用相反,并认为:电针及吗啡分别对SP-LI及ENK-LI的影响可用Jessell-Iversen氏一级传入信息在脊髓内加工的模式来解释,同时,SP与乙酰胆碱之间的功能联系也不能排除。含AChE神经元可能影响SP的释放。  相似文献   
992.
993.
The policy statement on infertility issued by the International Medical Advisory Panel of the International Planned Parenthood Federation (IPPF) and adopted by the Central Council of the IPPF in November, 1984, is provided. The IPPF recognizes that subinfertility and infertility is a part of family planning and provides suggestions for how Family Planning Associations (FPAs) can provide supportive assistance in this area of concern. Depending on the facilities and resources available at specific clinics, FPS can provide preventive, counseling, diagnostic, treatment, and referral services. FPAs can play a major role in prevention. Many conditions which cause infertility are preventable, and these include sexually transmitted diseases, infections stemming from abortion and childbirth, and possibly tuberculosis. IUDs increase the risk of pelvic inflammatory disease and may increase the risk of infertility; however, a direct relationship between IUDs and infertility has not been established. Injectable contraceptives may delay the return of fertility but do not lead to permanent infertility. Barrier methods protect againsr sexually transmitted diseases, and oral contraceptives may provide protection from pelvic inflammatory disease. FPAs should be familiar with the major causes of infertility in their region and adopt an advocacy role by promoting community programs to control sexually transmitted diseases which may play a role in infertility, to improve obstetric care, to increase access to reproductive health services, and to provide reproductive educational services for adolescents. FPAs can work in cooporation with other agencies concerned with infertility prevention and management. FPAs can play a direct role by educating their clients about infertility prevention. Most FPAs do have have the facilities and personnel to provide diagnostic and treatment services, but they can provide referral services. They should establish a link with centers which are fully equipped to provide diagnostic and treatment services. FPAs, with appropriately trained personnel, may offer screening services such as taking sexual histories and providing instruction in the timing of sexual intercourse. Clinics, with appropriate laboratory facilities, may offer endometrial biopsy, postcoital testing, and semen analysis.  相似文献   
994.
为了实现科技期刊编辑、出版发行工作的电子化,推进科技信息交流的网络化进程,我刊现已入网“万方数据资源系统(ChinaInfo)数字化期刊群”。所以,向本刊投稿并录用的稿件文章,将一律由编辑部统一纳入万方数据资源系统(ChinaInfo),进入因特网提供信息服务。凡有不同意者,请另投它刊。本刊对编入的文稿,均不再另付稿酬。   万方数据资源系统数字化期刊群是国家“九五”重点科技攻关项目,截至1999年底,已有1000种期刊全文上网(网址:http:∥www.chinainfo.gov.cn/periodical)。本刊全文内容按照统一格式制作编入万方数据资源系统后,读者可通过因特网进入万方数据资源系统(ChinaInfo)免费(一年后开始酌情收费)查询浏览本刊内容,也欢迎各界朋友向我刊提出宝贵意见、建议,或订阅本刊。 《河南医学研究》编辑部 二○○一年二月第10卷  相似文献   
995.
为探索和建立人工哺育树鼩的可行方法,将5对成年树鼩配对后饲养在繁殖笼内,喂与由标准动物粉状饲料、奶酪、新鲜蔬菜和水果构成的混合食物.新生树鼩出生后立即从母笼移出至孵育箱,每日人工喂与专门配制的牛奶制品.三周后将小树鼩从孵育箱移出,经喂与转换食物约10 d,过度到自食成年食物.结果7个月内5对成年树鼠句在共产11窝31只仔树鼩.在27只出生后人工喂养的仔树鼩中,25只健康存活至进入动物实验,人工喂养成活率为92.6%.树鼩平均产仔间隔52±8.9 d;平均窝产仔数2.8±0.4只.人工哺育树鼩的成功为提供树鼩应用于医学实验研究,尤其是与肝癌、肝炎有关的研究,开拓了广阔的前景.  相似文献   
996.
997.
Tea is a famous beverage that is produced from leaves of Camellia sinensis. Amongst the six major tea categories in China, dark tea is the only one that involves microbial fermentation in the manufacturing process, which contributes unique flavors and functions for the tea. In the recent decade, the reports about the biofunctions of dark teas have increased rapidly. Therefore it may be the proper time to consider dark tea as one potential homology of medicine and food. In this viewpoint, our current understanding of the chemical constituents, biological activities and possible health beneficial effects of dark teas were introduced. Some future directions and challenges to the development perspectives of dark teas were also discussed.  相似文献   
998.
Purpose The poor prognosis in patients with floating knee injuries is mainly contributed to articular involvement(Fraser’s typeⅡ).This study aims to evaluate and compare the functional outcomes among different Fraser’s typeⅡfloating knee injuries after surgical management.Methods Twenty-seven patients with Fraser’s typeⅡfloating knee injuries(54 fractures)between September 2014 and December 2015 were enrolled prospectively in this study and were distributed according to Fraser’s floating knee classification into three different groups as typeⅡA(ipsilateral femoral shaft and tibial intra-articular involvement,n=11),typeⅡB(ipsilateral tibial shaft and femoral intra-articular involvement,n=9)and typeⅡC(both femoral and tibial intra-articular involvement,n=7).The differences among the groups were evaluated and compared.The functional outcomes of these injuries at one year were analyzed using Knee Injury and Osteoarthritis Outcome Score(KOOS)which covers 5 subscales of pain,other symptoms,activities of daily living,sports and recreation,and quality of life.The result was also compared with standardized age-sex matched healthy population using paired samples t-test.Results All the patients were male,and the injury mechanism was solely roadside accident.The mean age was 29.8 years and injury severity score 17.9(comparable in all the three groups).Most injuries were observed on the right side(20 cases,74.1%).Based on paired samples t-test,the KOOS score of patients with Fraser’s typeⅡA was found to be better than that of typeⅡB and typeⅡC.Compared with the reference age-sex matched control group,patients with Fraser’s typeⅡB andⅡC fractures had significantly lower mean score in all KOOS subscales(all p<0.01).However,Fraser’s typeⅡA only revealed significant difference regarding the subscales of activities of daily living(p<0.0001),sports and recreation(p<0.0001),and quality of life(p<0.0001).Conclusion The results of this study show that patients with Fraser’s typeⅡA fractures had a better functional outcome as compared to those with typeⅡB andⅡC fractures.This might be due to the open intra-articular involvement of the distal femur of the latter two fracture types.  相似文献   
999.
Purpose: There is a common opinion that spinal fractures usually reflect the substantial impact of injuries and therefore may be used as a marker of significant associated injuries, specifically for intraabdominal injury (IAI). The impact of concomitant spinal cord injury (SCI) with the risk of associated IAI has not been well clarified. The aim of this study was to evaluate the incidence and severity of IAIs in patients suffering from spinal fractures with or without SCI. Methods: A retrospective cohort study using the Israeli National Trauma Registry was conducted. Patients with thoracic, lumbar and thoracolumbar fractures resulting from blunt mechanisms of injury from January 1, 1997 to December 31, 2018 were examined, comparing the incidence, severity and mortality of IAIs in patients with or without SCI. The collected variables included age, gender, mechanism of injury, incidence and severity of the concomitant IAIs and pelvic fractures, abbreviated injury scale, injury severity score, and mortality. Statistical analysis was performed using GraphPad InStat ® Version 3.10, with Chi-square test for independence and two sided Fisher’s exact probability test. Results: Review of the Israeli National Trauma Database revealed a total of 16,878 patients with spinal fractures. Combined thoracic and lumbar fractures were observed in 1272 patients (7.5%), isolated thoracic fractures in 4967 patients (29.4%) and isolated lumbar fractures in 10,639 patients (63.0%). The incidence of concomitant SCI was found in 4.95% (63/1272), 7.65% (380/4967) and 2.50% (266/10639) of these patients, respectively. The overall mortality was 2.5%, proving higher among isolated thoracic fracture patient than among isolated lumbar fracture counterparts (11.3% vs. 4.6%, p < 0.001). Isolated thoracic fractures with SCI were significantly more likely to die than non-SCI counterparts (8.2% vs. 3.1%, p < 0.001). There were no differences in the incidence of IAIs between patients with or without SCI following thoracolumbar fractures overall or in isolated thoracic fractures; although isolated lumbar fractures patients with SCI were more likely to have renal (3.4% vs. 1.6%, p = 0.02) or bowel injuries (2.3% vs. 1.0%, p = 0.04) than the non-SCI counterparts. Conclusion: SCI in the setting of thoracolumbar fracture does not appear to be a marker for associated IAI. However, in a subset of isolated lumbar fractures, SCI patient is associated with increased risks for renal and bowel injury.  相似文献   
1000.
Purpose: Injuries are one of the leading causes of death and lead to a high social and financial burden. Injury patterns can vary significantly among different age groups and body regions. This study aimed to evaluate the relationship between mechanism of injury, patient comorbidities and severity of injuries. Methods: The study included trauma patients from July 2016 to June 2018, who were admitted to Sina Hospital, Tehran, Iran. The inclusion criteria were all injured patients who had at least one of the following: hospital length of stay more than 24 h, death in hospital, and transfer from the intensive care unit of another hospital. Data collection was performed using the National Trauma Registry of Iran minimum dataset. Results: The most common injury mechanism was road traffic injuries (49.0%), followed by falls (25.5%). The mean age of those who fell was significantly higher in comparison with other mechanisms (p < 0.001). Severe extremity injuries occurred more often in the fall group than in the vehicle collision group (69.0% vs. 43.5%, p < 0.001). Moreover, cases of severe multiple trauma were higher amongst vehicle collisions than injuries caused by falls (27.8% vs. 12.9%, p = 0.003). Conclusion: Comparing falls with motor vehicle collisions, patients who fell were older and sustained more extremity injuries. Patients injured by motor vehicle collision were more likely to have sustained multiple trauma than those presenting with falls. Recognition of the relationship between mechanisms and consequences of injuries may lead to more effective interventions.  相似文献   
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