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161.
Banana vascular wilt or Moko is a disease caused by Ralstonia solanacearum. This study aimed to sequence, assemble, annotate, and compare the genomes of R. solanacearum Moko ecotypes of different sequevar strains from Brazil. Average nucleotide identity analyses demonstrated a high correlation (> 96%) between the genome sequences of strains CCRMRs277 (sequevar IIA-24), CCRMRs287 (IIB-4), CCRMRs304 (IIA-24), and CCRMRsB7 (IIB-25), which were grouped into phylotypes IIA and IIB. The number of coding sequences present in chromosomes and megaplasmids varied from 3,070 to 3,521 and 1,669 to 1,750, respectively. Pangenome analysis identified 3,378 clusters in the chromosomes, of which 2,604 were shared by all four analyzed genomes and 2,580 were single copies. In megaplasmids, 1,834 clusters were identified, of which 1,005 were shared by all four genomes and 992 were identified as single copies. Strains CCRMRsB7 and CCRMRs287 differed from the others by having unique clusters in both their chromosomes and megaplasmids, and CCRMRsB7 possessed the largest genome among all Moko ecotype strains sequenced to date. Therefore, the genomic information obtained in this study provides a theoretical basis for the identification, characterization, and phylogenetic analysis of R. solanacearum Moko ecotypes.  相似文献   
162.
Six llamas and 6 alpacas were mated to vasectomized males; ovulation and corpus luteum formation followed. Progesterone in blood was elevated from day 5 and reached maximum concentrations of 10–20 nmol/1 on day 7–8. A rapid decline in progesterone levels occurred on day 9–10 in connection with repeated surge releases of prostaglandin F2α. Oestradiol-17β levels were > 100–200 pmol/1 during oestrus when the animals were mated. These high levels might have been caused by coital stimulation. A temporary increase was detected in connection with the rise in progesterone levels in the early luteal phase. With this exception levels of oestradiol stayed low, 20–40 pmol/1 during the luteal phase but rose in most animals after luteolysis to 40–60 pmol/1.  相似文献   
163.
  1. Semiochemicals are powerful tools for the surveillance and suppression of forest insects. Although the literature on the chemical ecology of and use of semiochemicals to manage the Cerambycidae is growing, little is known about the chemical ecology of Cerambycidae fauna in Peru.
  2. Trapping studies that screen known attractants in off-shore mitigation programs can provide valuable baseline knowledge to inform management of species introduced outside their native range.
  3. Known Cerambycidae pheromones were screened for activity in a year-long field study in Peru to look for activity in the local Cerambycidae fauna.
  4. The most frequently captured species were Megacyllene andesiana (Casey), Oreodera bituberculata Bates, Aegomorphus longitarsis (Bates) and Discopus eques Bates.
  5. The activity period of A. longitarsis, O. bituberculata and D. eques occurred in mid-September 2020 and for M. andesiana occurred in early October 2020.
  6. Responses to anti-2,3-hexanediol, fuscumol and fuscumol acetate by M. andesiana, O. bituberculata and D. eques were observed.
  7. We observed antagonism of the responses of M. andesiana, O. bituberculata and D. eques when anti-2,3-hexanediol, fuscumol and fuscumol acetate were tested in blends.
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164.
165.
An hypothesis suggesting that acrolein might form part of a universal cell-growth regulatory system is presented. This unsaturated aldehyde appears, better than any other compound proposed so far, to fulfill the structural requirements and characteristics of the universal growth-inhibitor predicted in Szent-Gyorgyi's bioelectronic theory.  相似文献   
166.
P A de Alarcon 《Blood cells》1989,15(1):173-185
Megakaryocyte colony-stimulating activity (Mk-CSA) is required for in vitro megakaryocyte colony formation. Its in vivo significance in megakaryocytopoiesis is unknown. We studied 12 patients undergoing bone marrow transplantation (BMT) at our institution. The bone marrow megakaryocyte progenitor cells (CFU-Mk), the serum level of Mk-CSA, and the platelet count on the 28th day after BMT were studied. Patients with elevated Mk-CSA levels had less CFU-Mk in their bone marrow than did patients with a normal or decreased Mk-CSA (p less than 0.01). Animal experiments using murine models have documented that several purified molecules including erythropoietin, multi-CSF and GM-CSF possess Mk-CSA. The in vitro Mk-CSF of WEHI-3-conditioned medium is multi-CSF. The in vivo significance for megakaryocytopoiesis of these factors is not clear. In the human system, Mk-CSA is increased in conditions with decreased bone marrow megakaryocytes. Recombinant human or primate CSFs have in vitro Mk-CSA utilizing both human and murine cells as targets. However, the presence of these activities does not fully explain the Mk-CSA in human serum rich in Mk-CSA. The precise regulation of human blood cell levels and the studies discussed suggest that there is a specific Mk-CSF that responds to in vivo changes in megakaryocyte numbers. Proof of its physiologic role awaits the isolation of a pure factor.  相似文献   
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