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排序方式: 共有940条查询结果,搜索用时 125 毫秒
931.
Oniel J. Aguirre Gil Richard Paredes-Espinosa Rosel Aguilar Briones Iris Mezones Alarcon Tania E. Guerrero Vejarano Marcela L. Monné Andrés González Jeremy Allison 《Agricultural and Forest Entomology》2021,23(4):506-511
- 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.
- 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.
- Known Cerambycidae pheromones were screened for activity in a year-long field study in Peru to look for activity in the local Cerambycidae fauna.
- The most frequently captured species were Megacyllene andesiana (Casey), Oreodera bituberculata Bates, Aegomorphus longitarsis (Bates) and Discopus eques Bates.
- 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.
- Responses to anti-2,3-hexanediol, fuscumol and fuscumol acetate by M. andesiana, O. bituberculata and D. eques were observed.
- 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.
932.
Brissia Lazalde Jesús Grijalva‐Flores Fernando Guerrero‐Romero 《Birth defects research. Part A, Clinical and molecular teratology》2012,94(4):249-252
BACKGROUND Cyclophosphamide (CPA) is an alkylating agent widely used as an immunosuppressive agent in the treatment of several autoimmune diseases, including systemic lupus erythematosus. Its teratogenic effect has been well studied in different experimental mammalian and non‐mammalian animal models. In humans, 11 cases of CPA teratogenesis have been documented. CASE We present a case of a patient with Klippel‐Feil syndrome inadvertently exposed to CPA and prednisone in utero during the first trimester. CONCLUSIONS This case of possible cyclophosphamide embryopathy provides evidence of teratogenesis as an etiologic agent in developmental field defects such as Klippel‐Feil syndrome. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc. 相似文献
933.
G. Liébanas P. Guerrero J.-M. Martín-García R. Pe?a-Santiago 《Journal of nematology》2004,36(2):114-122
The aim of this study was to determine the incidence of 18 environmental variables in the spatial distribution of 30 chorotypes (species groups with significantly similar distribution patterns) of dorylaimid and mononchid nematodes by means of logistic regression in a natural area in the southeastern Iberian Peninsula. Six variables (elevation, color chroma, clay content, nitrogen content, CaCO₃, and plant community associated) were the most important environmental factors that helped explain the distribution of chorotypes. The distribution of most chorotypes was characterized by some (one to three) environmental variables; only two chorotypes were characterized by five or more variables, and four have not been characterized. 相似文献
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Luz M. Castillo Carlos A. Guerrero Orlando Acosta 《Journal of molecular histology》2017,48(3):169-185
Bone is a metabolically active organ subjected to continuous remodeling process that involves resorption by osteoclast and subsequent formation by osteoblasts. Osteoclast involvement in this physiological event is regulated by macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor κB ligand (RANKL). Fusion of mono-nuclear pre-osteoclasts is a critical event for osteoclast differentiation and for bone resorption. Here we show that PBMCs can be successfully fused with polyethylenglicol (PEG) in order to generated viable osteoclast-like cells that exhibit tartrate-resistant acid phosphatase (TRAP) and bone resorptive activities. PEG-fused PBMCs expressed additional markers compatible with osteoclastogenic differentiation such as carbonic anhydrase II (CAII), calcitonin receptor (CR), cathepsin K (Cat K), vacuolar ATPase (V-ATPase) subunit C1 (V-ATPase), integrin β3, RANK and cell surface aminopeptidase N/CD13. Actin redistribution in PEG-fused cells was found to be affected by cell cycle synchronization at G0/G1 or G2/M phases. PEG-induced fusion also led to expression of tyrosine kinases c-Src and Syk in their phosphorylated state. Scanning electron microscopy images showed morphological features typical of osteoclast-like cells. The results here shown allow concluding that PEG-induced fusion of PBMCs provides a suitable model system for understanding the mechanisms involved in osteoclastogenesis and for assaying new therapeutic strategies. 相似文献
938.
Question: This study analysed the effect of severe soil erosion on species composition of plant communities by favouring species showing certain growth forms, root‐sprouting and clonal growth abilities. Location: The study area was located between the middle Ebro Valley and the Pre‐Pyrenees (northeastern Spain). Methods: Root‐sprouting and shoot‐rooting abilities, clonal reproduction and growth form were assessed for the 123 most common plant species from eroded lands in the study area. We obtained 260 vegetation relevés in three different substrata (gypsum outcrops, Miocene clays and Eocene marls) on areas with different degrees of soil erosion. The frequency of every plant trait in each relevé was estimated according to species presence. The effect of soil erosion on the frequency of plant attributes was assessed by correlation analyses. Results: Bipolar, non‐clonal plants and annual species decreased their frequency with increasing soil erosion in the three substrata analyzed, whereas root‐sprouters and woody plants (mostly sub‐shrubs) increased their frequency in most of the substrata analysed. Conclusions: Woody sub‐shrubs, root‐sprouters and clonal species are favoured in eroded lands in NE Spain. Bipolar species and annual plants might not be plastic enough to survive the high stress and frequent disturbances prevailing in such eroded areas. 相似文献
939.
Cultures of Bdellovibrio isolated from different geographic locations have been studied in terms of deoxyribonucleic acid analysis (% G + C, genome size, and DNA hybridization), cytochrome spectrum, and host range. Isolates of the genus exhibit a broad range of % G + C ranging from 37 to 51% and the genome sizes extend from 1300 x 10(6) to 1700 x 10(6) daltons. DNA hybridization continues to reveal a high level of genetic heterogeneity. Bdellovibrio 3294 exhibits 32% relative reassociation to Bdellovibrio W, 37% to Bdellovibrio stolpii Uki2, and an undetectible level to Bdellovibrio starrii A3.12 Bdellovibrio W is 23% related to B. starri A3.12 and 28.5% to B. stolpii Uki2. For the first time differential absorption techniques have revealed peaks of cytochrome b. The analysis of the cytochrome spectrum seems to be limited as a taxonomic tool since most of the recent isolates studied share a common cytochrome spectrum. Host-range studies have been found to be dependent on the experimental conditions, and with the exception of one isolate (B. starrii A3.12) the taxonomic significance of such techniques must be taken with caution. 相似文献
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