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941.
The mouse conceptus is generally held to be radially symmetrical about its embryonic-abembryonic axis from the blastocyst stage until the primitive streak appears at the beginning of gastrulation. However, this notion has been challenged by recent observations on conceptuses sectioned in utero which suggest that the blastocyst is already bilaterally symmetrical when it begins to implant. Accordingly, the blastocyst has been assigned an anterior-posterior axis which appears to persist through gastrulation and is claimed to coincide with the anterior-posterior axis of the future fetus in both orientation and polarity. In the present investigation the relationship between these two axes was examined in conceptuses dissected from the uterus early in gastrulation so that it could be determined more accurately than is possible in situ. The anterior-posterior axis of the conceptus and nascent fetus were found to be either parallel or antiparallel to each other, suggesting that while the orientation of the fetal axis may be specified at the blastocyst stage its polarity is not. 相似文献
942.
Molecular Ecology Resources Primer Development Consortium Arias MC Arnoux E Bell JJ Bernadou A Bino G Blatrix R Bourguet D Carrea C Clamens AL Cunha HA d'Alençon E Ding Y Djieto-Lordon C Dubois MP Dumas P Eraud C Faivre B Francisco FO Françoso E Garcia M Gardner JP Garnier S Gimenez S Gold JR Harris DJ He G Hellemans B Hollenbeck CM Jing S Kergoat GJ Liu B McDowell JR McKey D Miller TL Newton E Pagenkopp Lohan KM Papetti C Paterson I Peccoud J Peng X Piatscheck F Ponsard S Reece KS Reisser CM 《Molecular ecology resources》2012,12(3):570-572
This article documents the addition of 473 microsatellite marker loci and 71 pairs of single‐nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Barteria fistulosa, Bombus morio, Galaxias platei, Hematodinium perezi, Macrocentrus cingulum Brischke (a.k.a. M. abdominalis Fab., M. grandii Goidanich or M. gifuensis Ashmead), Micropogonias furnieri, Nerita melanotragus, Nilaparvata lugens Stål, Sciaenops ocellatus, Scomber scombrus, Spodoptera frugiperda and Turdus lherminieri. These loci were cross‐tested on the following species: Barteria dewevrei, Barteria nigritana, Barteria solida, Cynoscion acoupa, Cynoscion jamaicensis, Cynoscion leiarchus, Cynoscion nebulosus, Cynoscion striatus, Cynoscion virescens, Macrodon ancylodon, Menticirrhus americanus, Nilaparvata muiri and Umbrina canosai. This article also documents the addition of 116 sequencing primer pairs for Dicentrarchus labrax. 相似文献
943.
R. N. Crowhurst R. C. Gardner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,81(1):71-78
Summary Six members of a family of moderately repetitive DNA sequences from kiwifruit (Actinidia deliciosa var. deliciosa) have been cloned and characterized. The repeat family is composed of elements that have a unit length of 463 bp, are highly methylated, occur in tandem arrays of at least 50 kb in length, and constitute about 0.5% of the kiwifruit genome. Individual elements diverge in nucleotide sequence by up to 5%, which suggests that the repeat sequence is evolving rapidly. Homologous sequences were found in A. deliciosa var. chlorocarpa. The repeat sequence was not found under low stringency hybridization conditions in the diploid A. chinensis, the species most closely related to the hexaploid kiwifruit, or in eight other Actinidia species. However, homologous repeats were detected in a tetraploid species, A. chrysantha. The results provide the first molecular evidence to suggest that kiwifruit may be an allopolyploid species. 相似文献
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946.
A S Khan T A Galvin M B Jennings M B Gardner L J Lowenstine 《Journal of medical primatology》1991,20(4):167-171
Analysis of molecularly cloned DNAs of SIVs isolated from Asian rhesus macaque (Macaca mulatta; SIVmac) and pig-tailed macaque (Macaca nemestrina; SIVmne) has indicated a high degree of sequence homology between these viruses. Thus SIVmac and SIVmne might have originated from the same or very closely related viruses. We have cloned and sequenced a PCR-amplified segment containing the LTR sequences of SIV originating from a stump-tailed macaque (Macaca arctoides; SIVstm). Comparative sequence analysis indicates that SIVstm belongs to the SIV/HIV-2 group; however, it is genetically distinct from the other members. 相似文献
947.
Denervated frog sartorius muscles showed an approximately 2--3 fold increase of cyclic GMP in their end-plate rich regions which did not appear up to 5 weeks after denervation in the normally end-plate-free pelvic region. No increase in cyclic AMP was seen in these preparations. The results suggest that the increase of cyclic GMP is related to processes specific to the region in which end plates are normally present. 相似文献
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950.
Patrick J. O'Connor Michael A. Crowley Andrew W. Gardner James S. Skinner 《European journal of applied physiology and occupational physiology》1993,67(1):39-42
The purpose of this investigation was to examine the influence of daytime exercise on heart rate during sleep. Nine, untrained male college students volunteered to participate. They cycled at 75% maximum oxygen uptake, (
O2max) 30 min·day–1 for 12 weeks. The exercise duration was increased by 5 min every 4 weeks from 30 to 40 min per session. Post-training
O2max[mean (SE): 48.9 (1.7) ml · kg–1 · min–1] values were significantly (P<0.01) higher than pre-training [45.5 (1.8) ml-kg–1·min–1] values. Before and after training, sleeping heart rate was assessed on two separate nights. Data were obtained during a night following 30 min of daytime cycling at 75 (6) %
O2maxand on a night in which no daytime exercise was performed. A three-way repeated measures ANOVA [training status (pre-/post-training) × activity (exercise day/nonexercise day) × sleep time (18 epochs of 20 min each)] revealed a significant main effect for sleep time (P < 0.001) as well as a sleep time × training status interaction (P<0.02). No significant difference in sleeping heart rate was noted when exercise and non-exercise days were compared both before and after training. It is concluded that endurance training in these young adult men: (1) hastens the achievement of baseline heart rate during sleep, and (2) does not moderate the relationship between an acute bout of daytime exercise and sleeping heart rate. 相似文献