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31.
Kenneth S. Kendler Ellen E. Walters Kim R. Truett Andrew C. Heath Michael C. Neale Nicholas G. Martin Lindon J. Eaves 《Behavior genetics》1995,25(6):499-515
Self-report symptoms of anxiety are widely used in mental health and social science research as an index of current psychiatric
state. Previous twin studies have suggested that genetic factors account for a significant proportion of the variance in these
symptoms. To replicate and extend these findings, we examined self-report symtoms of panic-phobia and somatization in the
“Virginia 30,000” twin-family sample. Model fitting applied to 80 unique relationships in the twin-family pedigree produced
the following major results: (i) genetic effects were significant for both symptom factors, accounting for between 25 and
49% of the total variance, with the exception of symptoms of panic-phobia in females, where they accounted for 15–16% of the
variance; (ii) familial environmental effects were absent for symptoms of somatization, while for symptoms of panic-phobia
they accounted for a very small proportion of variance in males (≤1.2%) and a modest proportion in females (6–17%) (iii) spousal
correlations were present for both factors, ranging from +0.05 to +0.20; (iv) genetic factors which influenced symptoms were
generally the same in males and females, although their effect was greater in males; (v) heritability estimates were lower
in the population-based than in the volunteer sample; and (vi) when test-retest reliability was included in the model, results
suggest that genetic factors account for at least half of the stable variance for all symptom factors, except panic-phobia
in females. Our results support the validity of previous twin studies of self-report symptoms of anxiety and suggest that
genetic factors significantly influence these symptoms but familial-environmental factors play little or no etiologic role. 相似文献
32.
Cross education of muscular strength during unilateral resistance training and detraining 总被引:2,自引:0,他引:2
Shima N Ishida K Katayama K Morotome Y Sato Y Miyamura M 《European journal of applied physiology》2002,86(4):287-294
Abstract. The purpose of the present study was to examine the changes in maximum voluntary isometric contraction (MVC) in the contralateral
untrained limb during unilateral resistance training and detraining, and to examine the factors inducing these changes by
means of electrophysiological techniques. Nine healthy males trained their plantar flexor muscles unilaterally 4 days·week–1 for 6 weeks using 3 sets of 10–12 repetitions at 70–75% of one-repetition maximum a day, and detrained for 6 weeks. Progressive
unilateral resistance training significantly (P<0.05) increased MVC, integrated electromyogram (iEMG), and voluntary activation in the trained and contralateral untrained
limbs. The changes in MVC after training were significantly correlated with the changes in iEMG in both limbs. No significant
changes occurred in MVC, voluntary activation, and iEMG in the contralateral limb after detraining. The changes in MVC after
detraining did not correlate with the changes in voluntary activation or iEMG in either limb. Training and detraining did
not alter twitch and tetanic peak torques in either limb. These results suggest that the mechanisms underlying cross education
of muscular strength may be explained by central neural factors during training, but not solely so during detraining.
Electronic Publication 相似文献
33.
A novel role for shuttling SR proteins in mRNA translation 总被引:15,自引:1,他引:15
34.
Isolation and RNA-binding analysis of NAD+-isocitrate dehydrogenases from Kluyveromyces lactis and Schizosaccharomyces pombe 总被引:1,自引:0,他引:1
Krebs cycle NAD+-isocitrate dehydrogenase (Idh) binds to the 5-UTRs of all mitochondrial mRNAs in Saccharomyces cerevisiae. We hypothesize that this leader-binding activity plays a role in translational regulation, thereby linking mitochondrial
biogenesis to the need for respiratory function. Analysis of effects of leader binding on mitochondrial translation is complicated
by the involvement of the enzyme in mitochondrial metabolism. We have therefore searched for an Idh altered in RNA binding,
but retaining full enzyme activity. Idh from Kluyveromyces lactis and Schizosaccharomyces pombe was partially purified and examined for the ability to bind Cox2 mRNA. Sch. pombe Idh, like the S. cerevisiae enzyme, has high affinity for both its own, K. lactis and S. cerevisiaeCOX2 leaders. In contrast, Idh purified from K. lactis shows only low affinity for all mRNAs tested. To determine what distinguishes K. lactis Idh from S. cerevisiae Idh, genes encoding the two subunits of Idh in K. lactis were cloned and sequenced. Sequence comparison revealed high levels of similarity throughout the proteins, in particular
in regions involved in enzyme activity, co-factor and regulator binding. Non-conserved residues between the subunits from
the two yeasts are candidates for involvement in the interaction with RNA.
Received: 19 January 2000 / 24 March 2000 相似文献
35.
In vitro biosynthesis and core glycosylation of the histidine-rich protein of Plasmodium lophurae 总被引:2,自引:0,他引:2
We have characterized the early biosynthetic forms of the histidine-rich protein (HisRP), a major, granule-bound protein (Mr 58 000) of the avian malarial parasite Plasmodium lophurae. We have translated poly(A)-containing, size-selected parasite mRNA in the wheat germ cell-free system in the presence of [3H]histidine. HisRP was synthesized as a larger precursor (Mr 63 000). When dog pancreas microsomal membranes were present in the cell-free system during translation, a still larger form of HisRP (Mr 66 000) was detected. This larger form was segregated into the dog pancreas microsomal vesicles and was core glycosylated. Presumably, it corresponds to an intermediate form located in the parasite rough endoplasmic reticulum (RER). The difference in the Mr of approx. 8 000 between this RER associated 'pro' form and the granule-bound, mature form of HisRP suggests that proteolytic processing occurs upon transport from the RER to the granule. Segregation and core glycosylation were strictly coupled to translation and were not observed upon posttranslational addition of microsomal membranes. Thus, the early events in the biosynthesis of HisRP are similar to those established for secretory and lysosomal proteins. 相似文献
36.
汉区少数民族学生文化疏离感研究 总被引:2,自引:0,他引:2
目的:提出文化疏离感的操作性定义和初步的理论构想,为我国少数民族的文化认同和文化适应,以及少数民族青少年的教育培养提供比较重要的参考资料,为疏离感理论的丰富起到一定积极作用.方法:自编<汉区少数民族学生文化疏离感量表>,进行信效度考察以后对678名汉区少数民族学生进行调查.结果:1.文化疏离感及其四个子维度在地区主效应上均表现出显著差异,在年龄主效应上差异不显著;文化分离感和不和谐感在性别主效应上差异显著.2.文化疏离感及其两个子维度(文化孤立感和文化分离感)在年龄和地区,以及在年龄、地区和性别的交互作用上均表现出显著差异.3.影响文化疏离感及其文化孤立感、文化分离感、被控感三个维度的主要变量是学生小学前后居住地区的改变,而影响不和谐感的主要变量是性别.结论:小学前后居住地的改变会影响少数民族学生文化疏离感. 相似文献
37.
Potential impact of hormonal male contraception: cross-cultural implications for development of novel preparations 总被引:5,自引:0,他引:5
Martin CW Anderson RA Cheng L Ho PC van der Spuy Z Smith KB Glasier AF Everington D Baird DT 《Human reproduction (Oxford, England)》2000,15(3):637-645
The prospect of a hormonal male contraceptive is no longer distant. Data on the potential impact of this improvement in contraceptive provision, however, is limited, particularly between different cultures. We have therefore carried out a multi-centre study to assess men's attitudes to proposed novel hormonal methods. Questionnaire-based structured interviews were administered to men in Edinburgh, Cape Town, Shanghai and Hong Kong. Approximately 450 men were interviewed in Edinburgh, Shanghai and Hong Kong, and a slightly larger group (n = 493) in Cape Town to give samples (n > 150) of black, coloured and white men. Knowledge of existing male and female methods of contraception was high in all centres and groups. The majority of men welcomed a new hormonal method of contraception, 44-83% stating that they would use a male contraceptive pill. Overall, a pill was more acceptable than an injectable form (most popularly given at 3-6 month intervals); long-acting implants were least so except in Shanghai. Familiarity with comparable female methods appeared to influence acceptability, for both oral and injectable methods. Hong Kong was the only centre where a male method (condom) was currently the most commonly used; men there appeared to rate the convenience of condoms highly while being least likely to think that they provided effective protection against pregnancy compared to other centres, and were least enthusiastic about novel male methods. The acceptability of potential male hormonal methods of contraception was high in some groups but showed wide variability, determining factors including cultural background and current contraceptive usage. These results suggest that the emerging emphasis that men should have greater involvement in family planning will be substantiated when appropriate contraceptive methods become available. 相似文献
38.
(His)6 -eIF3s4融合蛋白在人乳腺癌细胞Bcap37中的表达 总被引:1,自引:0,他引:1
目的:构建真核细胞翻译起始因子3第4亚单位(eIF3s4)真核表达载体用于进一步功能研究。方法:设计引物,以K562细胞的总RNA为模板,采用RT-PCR方法扩增eIF3s4的全长编码区cDNA,克隆于pGEM-TEasy载体,经DNA测序并与GenBank数据库序列进行比对后,将该cDNA序列亚克隆于真核表达载体pcDNA4/HisMaxB载体,构建成(His)6-eIF3s4融合蛋白的表达载体,用LipofectamineTM2000瞬时转染人乳腺癌细胞株Bcap37,利用Westernblot方法检测(His)6-eIF3s4融合蛋白的表达。结果:DNA序列测定表明,利用RT-PCR方法克隆的eIF3s4全长编码区cDNA序列与GenBank数据库序列一致,Westernblot结果证实(His)6-eIF3s4融合蛋白在Bcap37细胞中获得预期表达。结论:成功地构建了eIF3s4的真核表达载体并在人乳腺癌细胞Bcap37中表达,为建立稳定的eIF3s4高表达细胞系,进而研究eIF3s4与肿瘤细胞多药耐药相关性打下了基础。 相似文献
39.
Eriksen HR Hellesnes B Staff P Ursin H 《International journal of behavioral medicine》2004,11(2):122-125
Subjective health complaints without or with minimal somatic findings (pain, fatigue) are common and frequent reasons for encounter with the general practitioner and for long-term sickness leave and disability. The complaints are often attributed to the stressors of modern life. Is this true? We interviewed 120 Aborigine Mangyans (native population, M age = 33.5 years, 72.5% women) living under primitive conditions in the jungle of Mindoro, an island in the Philippines, and 101 persons living in a small coastal town on the same island (coastal population, M age = 33.8 years, 60.4% women). Both groups had more musculoskeletal complaints, fatigue, mood changes, and gastrointestinal complaints than a representative sample from the Norwegian population (N = 1,243). Our common subjective health complaints, therefore, are not specific for industrialized societies. 相似文献
40.
To determine if the cellular factors La autoantigen (La) and polypyrimidine tract-binding protein (PTB) are required for hepatitis C virus (HCV) replication, we used siRNAs to silence these factors and then monitored their effect on HCV replication using quantitative RT-PCR. In addition, we determined the influence of PTB on the activity of the 3' noncoding region (NCR) of HCV and investigated its interaction with the components of the HCV replicase complex. We found that La is essential for efficient HCV replication while PTB appears to partially repress replication. PTB does, however, block the binding of HCV RNA-dependent RNA polymerase (RdRp, NS5B) to the 3'NCR. Indirect immunofluorescence microscopy showed co-localization of cytoplasmic PTB with the HCV RdRp in hepatoma cells (Huh-7) expressing HCV proteins, while in vitro translation of viral proteins from the HCV replicon revealed the interaction of PTB isoforms with NS5B polymerase and NS3. 相似文献