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31.
Paul Grun 《Sexual plant reproduction》1991,4(1):56-63
Summary Reciprocal crosses were made between plants that had nuclear genes of S.tuberosum L. ssp tuberosum combinated, by recurrent backrossing, with cytoplasmic factors of S. phureja Juz. & Buk. and, separately, of S. tuberosum ssp. andigena (Juz. & Buk.) Hawkes. Significant differences in growth between 19 of 23 intra-cytoplasmic reciprocal progenies occurred in vigor at one or more growth stages during the season and/or in yield as measured by tuber number and weight. If no transmission of cytoplasmic factors occurred through the pollen, the cytoplasmic factors of the parents were the same, and these reciprocal differences were caused by parental chromosomal gene mechanisms such as maternal effect, pollen-tube selection, and/or imprinting. Early seedling vigor was, in some cases, associated with greater seed weight, but this did not account for all of the reciprocal contrasts. The data do not show whether these parental effects are a result of maternal and/or paternal effects. Analysis to determine whether parental effect was a single gene character or alleles expressed at two levels, or multi-genic and so expressed at multiple levels, was based on a study of progeny of ten parents that were used in more than one reciprocal pair combination. The data showed that the parents could be classified at eight successive levels of relative effectiveness as staminate or pistillate parents. Of 23 crosses, 19 showed significant differences between reciprocal progenies that were consistent with this eight-level array. The data support the interpretation that parental effect is a multi-genic character.Authorized for publication as paper No. 163 of the Department of Horticulture 相似文献
32.
Dicephalic — ADrosophila mutant affecting polarity in follicle organization and embryonic patterning
Margit Lohs-Schardin 《Development genes and evolution》1982,191(1):28-36
Summary The mutationdicephalic (dic) affects follicle development and thereby alters the antero-posterior polarity of embryonic patterning. It maps at a single locus (3–46.0±1.0) and can be characterized as a semi-dominant maternal effect mutation with low penetrance. Indic follicles, the 15 nurse cells form two clusters located at opposite poles of the oocyte; the numerical distribution of the nurse cells among the clusters varies from 7:8 to 1:14. Thedic egg shell carries a micropyle (anterior marker) at either pole, but the misshapen respiratory appendages are restricted to one of the two poles in most eggs. The malformed eggs rarely yield larvae and these are always abnormal anteriorly and/or posteriorly. The segment pattern expressed in their cuticle may represent two anterior parts of opposite polarities (double head type), two posterior parts of opposite polarities (double abdomen type, rare) or show uniform polarity. Lability of organization at the cystocyte stage appears as the primary developmental defect of the mutant. 相似文献
33.
J. F. Hayes E. J. Eisen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1979,55(5):209-223
Summary The effect of the postnatal maternal environment, simulated by rearing mice in litters of three, six or nine, on body weight and body composition was investigated in three lines of mice differing widely in growth rate. The lines were selected for high (H6) and low (L6) 6-week body weight while the control line was maintained by random selection. Body weight and weights and percentages of ether extract, water, ash and protein at 21, 42, 63 and 84 days were recorded. With few exceptions, there were positive correlated responses to selection in body weight and in weights of body components. At 21 and 42 days the correlated responses were larger in L6 mice than in H6 mice. Body weight and weights of body components were larger for mice reared in litters of three than for those reared in litters of nine. Also, mice reared in litters of six were intermediate in body weight and weights of some of the body components between those reared in litters of three and nine. Differences in body weight and weights of body components due to postnatal maternal environment were small by comparison with differences due to genetic line. There were significant line by maternal environment interactions in body weight at 21 days and in ether extract weight at 21 and 63 days. Line and maternal environment differences in percentages of body components did not follow any consistent trend. The results for percentages of body components were further complicated by line x maternal environment interactions. In general, both line and postnatal maternal environmental differences in percentages of body components diminished with age.Paper No. 5670 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, North Carolina 27650. The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Experiment Station of the products named, nor criticism of similar ones not mentioned 相似文献
34.
目的:研究持续镇痛分娩对产妇分娩结局和新生儿评分的影响。方法:选择2018年7月~2019年7月中国医科大学航空总医院(本院)采取硬膜外分娩镇痛的101例产妇,将其随机分为两组。当产生确切的镇痛效果,进入第二产程后,观察组的51例产妇采用0.4μg/m L舒芬太尼以及0.08%罗哌卡因进行持续镇痛分娩;对照组的50例产妇则在宫口开全后,使用生理盐水替代泵内的局麻药物,直到分娩结束。比较两组产妇催产素的使用率,宫口扩张度和第一、第二产程按压硬膜外自控镇痛泵的次数,分娩方式,新生儿的体质量,脐动脉血pH值,出生后1 min和5 min Apgar评分,产妇修复会阴部时的视觉模拟评分(visual analogue scale, VAS)评分及产妇对于第二产程镇痛的满意度评分。结果:两组产妇催产素的使用率、宫口扩张度和第一、第二产程按压硬膜外自控镇痛泵的次数、分娩方式(剖宫产率、器械助产率、自然分娩率)、第一产程镇痛时间、第一以及第二产程时间相比均无显著差异(P0.05);两组新生儿的体质量,脐动脉血pH值,出生后1 min和5 min Apgar评分小于8分的新生儿所占的比例相比没有明显的差异(P0.05);观察组产妇修复会阴部时的VAS评分明显低于对照组(P0.05),产妇对于第二产程镇痛的满意度评分明显高于对照组(P0.05)。结论:持续镇痛分娩对产妇分娩结局和新生儿评分无明显的影响,但可显著提高产妇对第二产程镇痛和修复会阴部时镇痛的满意度。 相似文献
35.
摘要 目的:研究妊娠期母体甲状腺功能减退对胎鼠骨骼肌胰岛素抵抗和线粒体功能的影响。方法:构建妊娠期母体甲状腺功能减退小鼠模型,制备胎鼠骨骼肌线粒体,同时选取健康正常胎鼠做本次实验的对照组。采用酶联免疫吸附法和放射免疫分析法测定两组小鼠甲状腺功能;通过全自动生化分析仪检测两组胎鼠胰岛素抵抗结果;利用Clark氧电极测定密闭反应体系评价两组胎鼠线粒体功能结果,并分析母体甲状腺功能减退与胎鼠骨骼肌胰岛素抵抗和线粒体功能的相关性。结果:两组小鼠甲状腺功能结果、两组胎鼠骨骼肌胰岛素抵抗和线粒体结果对比分析之间均有显著差异(P<0.05)。甲减组小鼠血清中促甲状腺激素(Thyroid Stimulating Hormone,TSH)、丙氨酸转氨酶(alanine aminotransferase,ALT)和门冬氨酸氨基转移酶(aspartate aminotransferase,AST)均较对照组低,胎鼠的空腹血糖(fasting blood-glucose,FBG)、动态3(state3,ST3)、动态4(state4,ST4)呼吸速率和呼吸控制比(respiratory control,RCR)也均较对照组低;而甲减组小鼠游离甲状腺素(free thyroxine,FT4)却较对照组高,胎鼠的胰岛素(insulin,INS)和胰岛素抵抗结果(homeostasis model assessment of insulin resistance,HOMA-IR)也较对照组高(P<0.05)。且母体甲状腺功能减退指标中FT4和RCR、ALT和FBG以及RCR之间有负相关关系,母体甲状腺功能减退的其他指标则与胎鼠骨骼肌胰岛素抵抗和线粒体功能的其他相关指标之间呈正相关关系(P<0.05)。结论:妊娠期母体甲状腺功能减退会降低胎鼠骨骼肌胰岛素抵抗和线粒体功能,影响胎鼠的正常发育。 相似文献
36.
《遗传学报》2021,48(10):899-907
Southern East Asia, including Guangxi and Fujian provinces in China, is home to diverse ethnic groups, languages, and cultures. Previous studies suggest a high complexity regarding population dynamics and the history of southern East Asians. However, large-scale genetic studies on ancient populations in this region are hindered by limited sample preservation. Here, using highly efficient DNA capture techniques, we obtain 48 complete mitochondrial genomes of individuals from Guangxi and Fujian in China and reconstruct their maternal genetic history over the past 12,000 years. We find a strong connection between southern East Asians dating to ~12,000–6000 years ago and present-day Southeast Asians. In addition, stronger genetic affinities to northern East Asians are observed in historical southern East Asians than Neolithic southern East Asians, suggesting increased interactions between northern and southern East Asians over time. Overall, we reveal dynamic connections between ancient southern East Asians and populations located in surrounding regions, as well as a shift in maternal genetic structure within the populations over time. 相似文献
37.
目的:分析重度妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)对母婴结局的影响,以提高对ICP的认识与治疗水平。方法:选择ICP产妇58例,根据ICP分度标准分为轻度组(n=26例)和重度组(n=32例),比较两组产妇的母婴结局。结果:与轻度组相比,重度组产妇剖宫产率、产后出血与平均产后出血量显著升高或增加,阴道分娩率显著降低,组间比较差异均具有统计学意义(P〈0.05);重度组新生儿早产、胎儿窘迫、羊水污染和新生儿窒息的发生率均显著上升,新生儿平均出生体重显著降低,组间比较差异均具有统计学意义(P〈0.05)。结论:ICP对产妇及新生儿均有不良影响,对ICP严重程度进行划分,有利于临床处理。对于重度ICP产妇,应尽早采取剖宫产分娩的方式终止妊娠。 相似文献
38.
39.
目的:评价中西药结合治疗对母儿ABO血型不合的疗效以及新生儿溶血发生与孕次关系的探讨。方法:对314例抗体滴度≥l:64的ABO母儿血型不合孕妇(20-45岁)进行研究,其中246例孕期给予以中西药结合治疗(茵陈蒿汤联合25%葡萄糖液、维生素C、维生素E、苯巴比妥),68例作为对照,观察孕妇IgG抗A/B抗体效价变化及新生儿溶血发生情况。结果:治疗组抗体效价降低与对照组相比,差异有统计学意义(P〈0.05),治疗组新生儿溶血发生率与对照组相比,差异有统计学意义(P〈0.05)。孕次越大,新生儿溶血的发生率越高。结论:中西药结合治疗对降低孕妇IgG抗A/B效价及防治新生儿溶血疗效满意,新生儿溶血发生可能与孕次呈正相关。 相似文献
40.
Laureline Formanek Marie‐Annick Richard‐Yris Cecilia Houdelier 《Chronobiology international》2013,30(3):396-414
Development involves interactions between genetic and environmental influences. Vertebrate mothers are generally the first individuals to encounter and interact with young animals. Thus, their role is primordial during ontogeny. The present study evaluated non‐genomic effects of mothers on the development of rhythms of precocial Japanese quail (Coturnix c. japonica). First, we investigated the influence of mothering on the ontogeny of endogenous rhythms of young. We compared circadian and ultradian rhythms of feeding activity of quail reared with or without adoptive mothers. More brooded than non‐brooded quail presented a circadian and/or an ultradian rhythm. Thus, the presence of the mother during the normal brooding period favors, in the long term, expression of rhythms in the young. Second, we investigated the influence of rhythmic phenotype of the mother on the development of endogenous rhythms of young by comparing quail brooded by circadian‐rhythmic adoptive mothers (R) to quail brooded by circadian‐arrhythmic adoptive mothers (A). More R‐brooded than A‐brooded quail expressed circadian rhythmicity, and circadian rhythm clarities were greater in R‐brooded than A‐brooded quail. Ultradian rhythmicity did not differ between R‐ and A‐brooded quail, nor between R and A adoptive mothers. Thus, the rhythmic phenotypes of quail mothers influence the rhythmic phenotypes of their young. Our results demonstrate that mothers of precocial birds influence epigenetically the ontogeny of endogenous rhythms of the young they raise. 相似文献