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可持续农业     
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Family rearing antecedents of pubertal timing   总被引:5,自引:2,他引:3  
Two general evolutionary hypotheses were tested on 756 White children (397 girls) studied longitudinally: (1) rearing experiences would predict pubertal timing; and (2) children would prove differentially susceptible to rearing. Analysis of pubertal measurements, including some based on repeated physical assessments, showed that mothering and fathering, earlier and later in childhood, predicted pubertal development, but only for girls, with negative parenting appearing most influential; maternal harsh control predicted earlier menarche. Rearing effects varied by infant negative emotionality, proving stronger (and opposite) for girls who in infancy were lower rather than higher in negativity. Maternal menarche, controlled in all analyses, was a stronger predictor than rearing. Findings are discussed in terms of theory development, genetic and nutritional influences, and sample restrictions.  相似文献   
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Scrophularia ningpoensis has long been used in the Chinese Materia Medica for inflammation. Like other herbal medicines, S. ningpoensis collected from different localities may considerably differ in their therapeutic efficacy, and the one grown in Zhejiang Province is recognized as geo-authentic. However, it is difficult to confirm the geographical authenticity by similar morphological characteristics. In the present study, inter-simple sequence repeat (ISSR) markers were conducted to detect S. ningpoensis from different origins. A 1 259-bp fragment amplified by primer UBC874 was found only in geo-authentic ones. By cloning and sequencing that specific band, sequence characterized amplified region (SCAR) markers were designed to distinguish geo-authentic S. ningpoensis from others. This is a rapid and easy method that can be used to identify the geographical authenticity of S. ningpoensis.  相似文献   
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To detect the site of mutation in RRDR of rpo B gene for rifampicin resistance in MDR-TB by DNA sequencing. 50 MDR-TB patients were enrolled in our study after informed written consent. Mycobacterial DNA was extracted from sputum samples by Universal Sample Processing (USP) method and RRDR of rpo B gene was amplified by PCR using primers RP4T and RP8T and then sequenced by automated DNA sequencing. The nucleotide sequences of RRDR of rpo B gene were compared with the reference sequence. We observed three different types of mutation in the RRDR of rpo B gene. The frequency of mutation in codon 531 (TCG → TTG), 526 (CAC → TAC) and 516 (GAC → GTC) are 60, 26.6 and 6.6% respectively. Of the total cases studied, 6.6% cases, although resistant to rifampicin, did not show any mutation in the RRDR of rpo B gene. Codon 531 (TCG → TTG) is the most common site of mutation in RRDR of rpo B gene for rifampicin resistance in MDR-pulmonary tuberculosis followed by codon 526 (CAC → TAC) and codon 516 (GAC → GTC).  相似文献   
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The present study examined personal and social correlates of poor sportspersonship among youth sport participants. Male and female athletes (n = 676) in the fifth through eighth grades from three geographic regions of the U.S. participated in the study. Young athletes involved in basketball, soccer, football, hockey, baseball/ softball, or lacrosse completed a questionnaire that tapped poor sportspersonship behaviors and attitudes, team sportspersonship norms, perceptions of the poor sportspersonship behaviors of coaches and spectators, and the sportspersonship norms of coaches and parents. Preliminary analyses revealed significant gender, grade, sport area, and location differences in self-reported unsportspersonlike behavior. The main analysis revealed that self-reported poor sport behaviors were best predicted by perceived coach and spectator behaviors, followed by team norms, sportspersonship attitudes, and the perceived norms of parents and coaches. Results are discussed in relation to the concept of moral atmosphere.  相似文献   
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基因疗法     
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