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51.
Intravenous self-administration of GBR 12909, an indirect dopamine agonist, was examined on a Fixed Ratio (FR 1) and a Progressive Ratio (PR) schedule of reinforcement in rats. Subjects were first trained to self-administer cocaine (1.5 mg/kg/inj) during daily 5 h sessions, after which GBR 12909 (0.187–1.5 mg/kg/inj) was substituted. On the FR 1 schedule, the inter-infusion interval for GBR 12909 self-administration was directly related to dose and was approximately three times longer than that established for equivalent doses of cocaine. Breaking points on the PR schedule were comparable for GBR 12909 and cocaine self-administration. The data indicate that, compared to cocaine, GBR 12909 has a longer duration of action and a similar reinforcing efficacy.  相似文献   
52.
本试验探讨了华南双季稻区利用亚种同杂种优势的特点和问题,结果表明:当前,两系亚种问杂种一代主要存在的问题是结实率低和谷草比低;籼粳交杂种易受环境条件的影响;每穗实粒数和单株有效穗数是决定单株产量的重要因子;每穗实粒数增加的关键在于结实率的提高,本文还就提高结实率和谷草比等问题提出了意见。  相似文献   
53.
创收工资—医院按劳分配的探索   总被引:1,自引:1,他引:0  
遵循“各尽所能,按劳分配”的社会主义分配原则,我院对职工分配进行了积极的探索。从80年代初起,在院内实行定量、定质的超额劳务提成。但随着医院改革不断深化,医院总收入增加,院内、外独立核算,限期还本息项目增多,原超额劳务提成办法不能适应医院发展。因此,在原有基本工资、奖励工资基础上,增设了创收工资,医院对创收工资从质量、数量、文明建设、医德医风建设等方面进行宏观调控。创收工资使科主任责、权、利落到实  相似文献   
54.
Summary: Summary. A study was conducted to determine whether the attitudes of medical students to death and caring changed during the 3 months following exposure to cadaver dissection. All first-year students were invited to complete a questionnaire immediately before their initial cadaver dissection experience, after 6 weeks, and after a further 3 months. The questionnaire reflected attitudes to death, violent death, death of someone known to the respondent and caring when someone known to the respondent is seriously injured. Ethnicity and previous exposure to dying has no effect on responses, but overall men students' reactions were significantly less than for women ( P < 0.001). The responses given on the final part of the questionnaire after 3 months were significantly lower than those to most questions in the first part of the questionnaire. The exceptions were those questions where the subject in the given scenario was known to the respondent, where reactions were rated significantly greater ( P < 0.001) in the follow-up questionnaire and can be explained on the basis that they were a personal referent.
Students rapidly develop a coping mechanism which enables them to view cadaver dissection as an occupation quite divorced from living human beings. During these early months of training solicitude decreases for those who die who are unknown to them, but concern for personal referents increases. Educators should be aware of the dramatic change of attitudes among students and the process of professionalization which might influence their caring of future patients.  相似文献   
55.
Primary extranodal malignant lymphoma frequently occurs in the gastrointestinal tract; however, it is rarely encountered in the rectum. We report herein the case of an 85-year-old man who underwent abdominoperineal resection for primary malignant lymphoma of the rectum, and 1 year later, developed hematemesis caused by gastric metastasis. To our knowledge this is the first case report of such distant metastasis developing from malignant lymphoma of the rectum.  相似文献   
56.
不同类型高危儿早期干预的临床研究   总被引:4,自引:0,他引:4  
目的 探索早期干预对窒息、高胆、早产三类高危儿智力发育改善的效果,寻找更合适的早期干预措施。方法 将三类高危儿分为干预组及对照组,同时随机选取正常对照组进行随访。干预组采用鲍秀兰教授“0~3岁”早期干预方案训练,各组均在6个月、1岁时分别采用婴幼儿智能发育量表(CDCC)进行智力发育测评,结果用MDI、PDI表示。结果 (1)6个月龄时MDI各干预组与对照组间有显著性差异,窒息组、早产组与正常组间亦有显著性差异;高胆组与正常组间无差异;PDI窒息组中干预组与对照组之间有显著差异(P<0.01),高胆组、早产组均无差异(P>0.05)。(2)1岁时MDI和PDI结果一致,干预组与对照组间比较窒息组、高胆组有显著差异,早产组无差异;窒息组、高胆组干预组与正常组比较无差异,对照组和早产组与正常组比较均有显著差异(P<0.01)。(3)所有干预组测评分值均高于对照组,6个月与1岁之间比较有显著差异,各观察组间比较有显著性差异(P<0.01)。结论 三类高危儿早期干预效果差异较大,干预组均较对照组分值高,早期干预有改善智力发育的作用;三类高危儿中,窒息组、高胆组效果最好,均达到或超过正常水平。所有未干预组均不及正常水平;早期干预对足月高危儿效果显著,对早产儿欠佳,远期效果尚需进一步随访观察。  相似文献   
57.
对AF系统整复压缩爆裂骨折椎体高度及椎管横截面的观测   总被引:4,自引:3,他引:1  
目的 :量化评价AF系统恢复胸腰段压缩爆裂椎体高度椎管截面积的效果。方法 :测量AF系统治疗的 72例胸腰段压缩爆裂骨折术前后影像。统计椎体前后缘高度、Cobb角、椎管截面积资料。结果 :术后伤椎前缘高度恢复至 ( 96.5± 2 .3 ) %后缘高度恢复至 ( 98.2± 0 .9) % ,Cobb角恢复至 ( 5 .4± 1.5 )° ,椎管截面积恢复至 ( 97.2± 2 .1% ) ,各项指标与术前比较有非常显著性差异 (P <0 .0 0 1)。术后随访 0 .5~ 3 .5年 ,神经功能按Frankel评定 :60例提高 1~ 3级。结论 :AF系统能恢复或基本恢复胸腰段压缩爆裂骨折椎体的前后缘高度、Cobb角、椎管容积 ,为脊髓神经功能的恢复提供一个良好的环境。是治疗脊柱胸腰段压缩爆裂骨折较好的内固定器。  相似文献   
58.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义   总被引:1,自引:1,他引:0  
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。  相似文献   
59.
Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c…  相似文献   
60.
BACKGROUND: The purpose of this study was to describe the health status and work limitations in injured workers with musculoskeletal disorders at 1 month post-injury, stratified by return-to-work status, and to document their return-to-work trajectories 6 months post-injury. METHODS: A sample of 632 workers with a back or upper extremity musculoskeletal disorder, who filed a Workplace Safety and Insurance Board lost-time claim injury, participated in this prospective study. Participants were assessed at baseline (1 month post-injury) and at 6 months follow-up. RESULTS: One month post-injury, poor physical health, high levels of depressive symptoms and high work limitations are prevalent in workers, including in those with a sustained first return to work. Workers with a sustained first return to work report a better health status and fewer work limitations than those who experienced a recurrence of work absence or who never returned to work. Six months post-injury, the rate of recurrence of work absence in the trajectories of injured workers who have made at least one return to work attempt is high (38%), including the rate for workers with an initial sustained first return to work (27%). CONCLUSIONS: There are return-to-work status specific health outcomes in injured workers. A sustained first return to work is not equivalent to a complete recovery from musculoskeletal disorders.  相似文献   
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