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1.
On five subjects, skin resistance levels and galvanic skin response were recorded unilaterally and simultaneously from each side of the body for between 24 and 36 days. Reliable differences in skin resistance were found in three subjects and in galvanic skin response in two subjects. The magnitude of the skin resistance difference was significantly reduced in four subjects during stimulation.  相似文献   

2.
Wilson's disease: identification of an abnormal copper-binding protein   总被引:5,自引:0,他引:5  
The metal-binding protein metallothionein was isolated from the livers of Wilson's disease patients and control subjects. The metals were removed from the native protein to produce the apoprotein, and copperthionein was prepared by equilibrium dialysis. Copperthionein from Wilson's disease patients had a copper-binding constant four times as great as that of the protein from control subjects. These results suggest that the alterations in copper homeostasis in Wilson's disease result from the synthesis of an abnormal metal-binding protein with an increased affinity for copper.  相似文献   

3.
The eflect of uncinectomny on the social behavior of free-ranging rhesus monkeys was observed on Cayo Santiago Island. Operated subjects showed social indifjerence, failed to display appropriate aggressive and submissive gestures. were expelled from their social group, and evenitlually died. Two juvenile subjects with the lesion restricted to amygdala survived and have rejoinied their social group. Size of lesion and age at operation were major factors in determniting the degree of behavioral change.  相似文献   

4.
以定量文献分析为基础的态势分析是厘清学科现状、识别发展方向的重要方法,为越来越多学科的战略布局提供着决策参考。运用共词分析与社会网络分析相结合的方法,研究了国际植物营养学学科发展态势。以SCI收录的三种国际植物营养学重要期刊2001-2014年刊载的论文为数据源,采用共词聚类对学科进行了主题领域划分,并研究了各领域的发展变化趋势;通过一模网络及二模网络对该学科重要研究机构合作网络的特征及研究布局进行了剖析。研究结果表明:基于共词聚类,2001-2014年国际植物营养学方面的研究大致可分为8个主题领域,其中,“拟南芥、基因表达、转录因子”和“动态、碳、生态系统”两个主题的增长势头较强;法国农业科学院、美国加州大学、荷兰瓦赫宁根大学和西班牙高等科学研究理事会等4家机构处于国际植物营养学合作网络的中心;中国科学院研究覆盖面最广,在7个研究主题上均有大量布局;“氮、磷、施肥”主题是主要机构的研究热点。因此,我国应重视在上升主题和热点主题上的布局,加强与合作网络中心机构的合作。本研究结果可为我国植物营养学科研人员和管理者布局研究重心、寻找合作对象提供参考,帮助其提高科研效率。  相似文献   

5.
Multiple fine-wire electrodes were implanted in the biceps brachii of five subjects, and artificial electronic feedback was provided to subjects from only one electrode. By this technique, it was shown that neighboring units progressively stop firing as subjects concentrate on activating an isolated unit. The inhibition of neighboring spinal motoneurons in the same pool further indicates that selective inhibition is an automatic part of single motor-unit training.  相似文献   

6.
Concentrations of dopamine-related tetrahydroisoquinolines (salsolinol and O-methylated salsolinol) were significantly higher in the daily urine samples of alcoholic subjects admitted for alcohol detoxification than in the daily urine samples of nonalcoholic control subjects. Salsolinol concentrations in alcoholic subjects appeared to drop to trace (control) values 2 to 3 days after admission, following the disappearance of ethanol and its reactive metabolite acetaldehyde from the blood. These results indicate that physiologically active tetrahydroisoquinolines increase in humans during long-term alcohol consumption, presumably because of acetaldehyde's direct condensation with catecholamines. The presence of these or similar condensation products in the urine could be useful as clinical indicators of prior blood acetaldehyde concentrations in chronic alcoholics.  相似文献   

7.
Conversion of thyroxine to triiodothyronine in normal human subjects   总被引:13,自引:0,他引:13  
The conversion of thyroxine to triiodothyronine, previously demonstrated in athyreotic human subjects, has been investigated in normal subjects who were given intravenous injections of purified thyroxine labeled with carbon-14 in ring A and in the alanine side chain. Evidence for the conversion of T4 to T3 was provided by the finding of carbon-14 in the T3 fraction isolated from serums. It is estimated that an appreciable fraction of T4 may be transformed to T3 in normal man.  相似文献   

8.
The acquired immune deficiency syndrome (AIDS), which has recently occurred at increasing rates in homosexual men, intravenous drug users, and others, is characterized by the development of Kaposi's sarcoma and several opportunistic infections including pneumonia caused by Pneumocystis carinii. Serum samples from patients with AIDS and from matched and unmatched control subjects were examined for the presence of antibodies to cell membrane antigens associated with human T-cell leukemia virus. Nineteen of 75 of the AIDS patients had antibodies directed to surface antigens of Hut 102, a reference T lymphoid cell line infected with leukemia virus, as did two of the 336 control subjects.  相似文献   

9.
基于SCI-E的中国大陆主要农业大学科研论文产出分析   总被引:1,自引:1,他引:0  
从发文量、学科分布、合作国家/地区与研究机构、语种等方面,统计分析了2000~2009年中国主要五所农业大学SCI-E论文产出情况。分析发现,按照产出量五所农业大学可以分为中国农业大学、南京农业大学和华中农业大学、西北农林科技大学和华南农业大学三个层次;五所大学的优势学科比较突出,但学科交叉重叠严重,国际合作研究少,合作机构面窄。  相似文献   

10.
Cultured fibroblasts derived from patients with late infantile metachromatic leukodystrophy incorporated arylsulfatase A from the growth medium. Upon exposure to cerebroside sulfate, they exhibited patterns of uptake and hydrolysis indistinguishable from cells derived from control subjects. Furthermore, inclusion granules formed in the metachromatic leukodystrophy fibroblasts upon exposure to sulfatides were cleared by subsequent supplementation of the growth medium with arylsulfatase A.  相似文献   

11.
目的:观察丹参对慢性肺源性心脏病(CCP)患者血浆神经降压素(NT)及神经肽Y(NPY)含量的影响。方法:用放射免疫分析法测定40例慢性肺源性心脏病患者血浆NT、NPY的水平,并以30例健康者作对照,观察CCP患者常规治疗及在其基础上加用丹参静脉滴注后NT和NPY的水平变化。结果:CCP患者血浆NT和NPY水平均明显高于对照组(P<0.05)。常规治疗及加用丹参治疗后NT、NPY水平均有明显下降,且丹参治疗组较常规治疗组下降更加显著(P<0.05)。结论:丹参可明显降低CCP患者血浆NT、NPY水平,对改善患者缺氧及心功能有重要作用。  相似文献   

12.
Cultured skin fibroblasts from subjects with clinically apparent diabetes mellitus and from subjects genetically predisposed to diabetes have a replicative lifespan that is inversely related to donor age. Fibroblasts from carefully defined normal subjects not predisposed to diabetes fail to show this correlation. The data support the idea that physiologic status of the tissue donor is a more precise determinant of fibroblast replicative lifespan than chronologic age.  相似文献   

13.
Visually evoked potentials: amplitude changes with age   总被引:1,自引:0,他引:1  
Visually evoked potentials of 215 subjects, aged 1 month to 81 years, were studied. Amplitudes of waves in the first 250 milliseconds of the response changed markedly with age. In responses recorded from the occiput, there was a rapid increase in amplitude reaching a maximum in the 5- to 6-year-old group, with means of amplitudes at this age being about twice as large as means of some older age groups. With children 7 years and older there was a rapid decline in amplitude until ages 13 to 14, when an abrupt increase in amplitude appeared. Amplitude appeared to stabilize at about age 16. In older subjects, mean age 60 and beyond, significant changes were noted in the earlier components of the response.  相似文献   

14.
Structure-disrupting ions: detection of qualitative change in an enzyme   总被引:1,自引:0,他引:1  
Preparations of erythrocyte glucose-6-phosphate dehydrogenase from normal individuals show similar degrees of inhibition by neutral salts. Preparations from Caucasian subjects with different hereditary deficiency syndromes differ from each other and from normal subjects, indicating a qualitative difference in these specific "deficient" enzymes. Sensitivity to neutral salts may be a means of detecting an amino acid substitution.  相似文献   

15.
首先从移民主体为贫困人口、数量大且素质较低以及社会适应性差等角度阐释开发移民人力资源的必要性;其次,指出了目前移民人力资源开发中存在的问题,教育和培训体系建设不到位、资金投入不足、移民观念落后等;最后提出要构建生态移民人力资源多元主体协同开发机制,促进主体间协同,发挥各主体的作用,促进移民人力资源开发。  相似文献   

16.
The incidence of the acquired immune deficiency syndrome (AIDS) among persons infected with human T-lymphotropic virus type III (HTLV-III) was evaluated prospectively among 725 persons who were at high risk of AIDS and had enrolled before October 1982 in cohort studies of homosexual men, parenteral drug users, and hemophiliacs. A total of 276 (38.1 percent) of the subjects were either HTLV-III seropositive at enrollment or developed HTLV-III antibodies subsequently. AIDS had developed in 28 (10.1 percent) of the seropositive subjects before August 1985. By actuarial survival calculations, the 3-year incidence of AIDS among all HTLV-III seropositive subjects was 34.2 percent in the cohort of homosexual men in Manhattan, New York, and 14.9 percent (range 8.0 to 17.2 percent) in the four other cohorts. Out of 117 subjects followed for a mean of 31 months after documented seroconversion, five (all hemophiliacs) developed AIDS 28 to 62 months after the estimated date of seroconversion, supporting the hypothesis that there is a long latency between acquisition of viral infection and the development of clinical AIDS. This long latency could account for the significantly higher AIDS incidence in the New York cohort compared with other cohorts if the virus entered the New York homosexual population before it entered the populations from which the other cohorts were drawn. However, risk of AIDS development in different populations may also depend on the presence of as yet unidentified cofactors.  相似文献   

17.
依据文献分布理论,选择15种科技学术期刊,就论文在不同主题内容上的分布情况进行了认真的调查与分析.结果表明,多数论文集中在核心主题上,少数论文分散在相关主题上.分布在核心主题上的论文为该刊的核心文献.分布在相关主题上的论文为该刊的相关文献.  相似文献   

18.
Mice were tested in a situation permitting them to step readily from a small, restrictive platform to a larger one. Conditioned avoidance was established by a single training trial when animals received a shock by stepping from one platform to another. At various intervals after the single punishing shock, subjects were anesthetized with diethyl ether. Interference with retention, tested 1 day later, was shown for intervals up to 24 minutes, at which time ether no longer appeared to influence the subsequent response.  相似文献   

19.
Murine leukemia viruses (MLVs), including xenotropic-MLV-related virus (XMRV), have been controversially linked to chronic fatigue syndrome (CFS). To explore this issue in greater depth, we compiled coded replicate samples of blood from 15 subjects previously reported to be XMRV/MLV-positive (14 with CFS) and from 15 healthy donors previously determined to be negative for the viruses. These samples were distributed in a blinded fashion to nine laboratories, which performed assays designed to detect XMRV/MLV nucleic acid, virus replication, and antibody. Only two laboratories reported evidence of XMRV/MLVs; however, replicate sample results showed disagreement, and reactivity was similar among CFS subjects and negative controls. These results indicate that current assays do not reproducibly detect XMRV/MLV in blood samples and that blood donor screening is not warranted.  相似文献   

20.
Eleven subjects squeezed an electronic dynamometer, at each of three force levels, with both their right and left hands. In right-handed subjects the premovement "readiness" potentials were larger over the hemisphere contralateral to the responding hand. Left-handed subjects show contralateral dominance when responding with the right hand but not when responding with the left hand. The data suggest that in the potentials studied there is a component associated with the preparation to perform a specific movement, rather than with generalized preparatory processes.  相似文献   

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