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S SPIEGEL D HOLLAND Y TAM I BAR-YAAKOV L MASLENIN A ROSNER 《The Annals of applied biology》2004,144(2):229-236
Prunus necrotic ringspot virus (PNRSV) was detected in almonds, plum and apricot germplasm accessions and local almond cultivars in Israel. PNRSV was widespread both in wild and cultivated almond trees and uncommon in wild apricots and plums. The possible variation among the PNRSV isolates was initially evaluated by restriction analysis of PCR products representing the CP gene with the endonuclease RsaI and followed by nucleotide sequence analysis of selected isolates. It was concluded that all 13 isolates belong to group PV96, the largest cluster of PNRSV isolates, described previously. Two PNRSV isolates, one from a plum accession and one from an almond cultivar, were found to be distinct members of group PV96 with unique nucleotide modifications not found in other documented isolates of this virus. However, no PNRSV isolate typical to a specific host and/or to the Middle East region could be identified. This study expands the body of data on variability of PNRSV isolates and highlights the importance of assessing the virus status of germplasm collections by applying reliable diagnostic and differentiating methods. 相似文献
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《L'Anthropologie》2023,127(2):103134
The most abundant evidence of Pampean Pleistocene human presence are modified bones, as lithic procurement sites located farther than 300 km away. Therefore, we focused on the study of bone modifications, in particular cut and percussion marks. We studied Pampean paleontological collections of Argentine and European museums as an alternative resource of previously unnoticed human modification evidences. We compared marks characteristics with those of archaeological collections from diverse climatic and cultural adaptations, from middle Pleistocene sites (Vallonet, Atapuerca, Lazaret, Arago and Terra Amata) to terminal Pleistocene ones (Abri Pataud, Isturiz and La Vache). Marks typologies were defined, leading to the identification of a particular cutmark that we named double parallel considered as highly diagnostic of anthropic use of lithic artifacts. We also propose that hafted artifacts were used on carcass processing. Perimortem bone modifications are classified in relation with mark morphology (e.g., percussion striae), inferred gesture or action (e.g., breakage of diaphysis), and inferred objective of that action (e.g., marrow extraction). The megafauna specimens analyzed from the historical collections (d’Angelis-Vilardebó, 1847, Muñiz-Dupotet, 1842 and Breton-Bonnement, 1881) present modifications compatible with dismemberment, defleshing, tongue and masseter extraction, and utilization as anvils. The lack of contextual data (location, stratigraphy) and the loss due to museum selection/collecting of accompanying material prevent paleoenvironmental and paleoecological inferences. Regional geology indicates that most of the historical collections were exhumed in riverbank cuts with ages between 70 and 13 ky BP. Preliminary direct dating presents evidence of a Pampean human occupation, at least, since OIS 2. 相似文献
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中国主要五针松群落学特征及其生物量的研究 总被引:10,自引:1,他引:10
本文根据现有的文献资料,系统地分析了中国五针松的分布.群落学特征,按不同分布区、不同群落类型探讨了中国五针松的群落生物量和年净生产量及在群落的不同层次上的分布.比较分析了不同分布区五针松的年干物质累积速度(NP/B).结果表明:115─135a生的阔叶红松林群落生物量在97.09─120.51t/hm ̄2之间,年净生产量在8.698─10.34t/hm ̄2.a之间,年净生产量长白山山脉沙松、鹅耳枥红松林>小兴安岭南坡枫桦、水曲柳红松林>小兴安岭北坡云杉、冷杉红松林;30─36a生的华山松林群落生物量在78.75─94.73t/hm ̄2之间,年净生产量在4.993─5.537t/hm ̄2.a之间,年净生产量贵州山地常绿阔叶华山松林>秦岭中山地阔叶华山松林>甘肃小陇山针阔叶华山松林.NP/B值:长白山山脉的阔叶红松林>小兴安岭山脉的阔叶红松林;秦岭中山地阔叶华山松林>甘肃小陇山针阔华山松林>贵州中山地常绿阔叶华山松林. 相似文献
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Suzuki Setsuko Kyoko Sugai Ichiro Tamaki Koji Takayama Hidetoshi Kato Hiroshi Yoshimaru 《Molecular ecology》2020,29(6):1050-1068
Pandanus boninensis, endemic to the Ogasawara Islands, Japan, is distributed on both the older Bonin and younger Volcano Islands. In this study, we conducted population genetic analyses of P. boninensis on these islands to examine the population diversity and structure across old and young islands, to assess potential differences in population demography with island age, and to collect any evidence of migration between old and young islands. We found that the genetic diversity of expressed sequence tag (EST)–based microsatellite (SSR) markers, the nucleotide diversity of nuclear DNA sequences, and the haplotype diversity of chloroplast DNA on young islands were lower than those on old islands. Clustering analyses of EST‐SSR indicated that populations on old islands were strongly diverged from those on young islands. Approximate Bayesian computation analysis of EST‐SSR suggested that population expansion occurred on old islands while population reduction occurred on young islands. We also found evidence of migration among old islands (mostly from south to north), while it appears that there have been very few migration events between old and young islands. These differences could be due to the fact that young islands tend to be geographically isolated and support smaller populations that began a shorter time ago from limited founders. The P. boninensis populations on the Volcano Islands are interesting from an evolutionary perspective as they constitute a classic example of the early stages of progressive colonization on oceanic islands with small effective population sizes and low genetic diversity. 相似文献
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《Nucleosides, nucleotides & nucleic acids》2013,32(8-9):1127-1129
The liquid chromatography‐mass spectrometry (LC‐MS) following on from the two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE) technique was applied for the analysis of proteins in a renal stone found in a hyperuricemic patient. This technique was sensitive enough to detect small quantities of proteins even in a renal stone. 相似文献
9.
Stone fruits and pome fruits are cultivated commercially worldwide. In India, they are grown in temperate regions, which mainly includes Jammu and Kashmir, Uttarakhand, Himachal Pradesh and some North-Eastern states. In this study, an attempt has been made to identify the Prunus necrotic ringspot virus (PNRSV) infecting stone and pome fruits in India and to characterise them on the molecular level. Surveys were conducted in the temperate fruit-growing areas and incidence of PNRSV was detected by serological and molecular means in almond, apple, cherry, nectarine, peach, plum and wild cherry. Further diversity analysis of PNRSV was performed using bioinformatics tools such as clustalW, DNA Data Bank of Japan, MultAlin and Recombination Detection Programme. PNRSV was detected in plum, peach, cherry, almond, nectarine, wild cherry and apple. In the diversity analysis study on the basis of coat protein gene, it was found that the isolates showed identity levels from 82 to 100%. In a plum isolate, a stretch of amino acids from 207 to 221 was found variable from Indian and other isolates. In one of the Indian apple isolates, “NR” repeats at 41–44 position (characteristic of PV-32 group, Group I) were identified. Phylogenetic analysis revealed that Indian isolates are falling in Group-I. Movement protein was also amplified from peach and multiple alignment studies showed that N-terminus was mostly conserved, whereas the C-terminal was highly variable. 相似文献
10.
Vera Y. Chung Rebecca Konietzny Philip Charles Benedikt Kessler Roman Fischer Benjamin W. Turney 《Fly》2016,10(2):91-100
Kidney stone disease is a major health burden with a complex and poorly understood pathophysiology. Drosophila Malpighian tubules have been shown to resemble human renal tubules in their physiological function. Herein, we have used Drosophila as a model to study the proteomic response to crystal formation induced by dietary manipulation in Malpighian tubules. Wild-type male flies were reared in parallel groups on standard medium supplemented with lithogenic agents: control, Sodium Oxalate (NaOx) and Ethylene Glycol (EG). Malpighian tubules were dissected after 2 weeks to visualize crystals with polarized light microscopy. The parallel group was dissected for protein extraction. A new method of Gel Assisted Sample Preparation (GASP) was used for protein extraction. Differentially abundant proteins (p<0.05) were identified by label-free quantitative proteomic analysis in flies fed with NaOx and EG diet compared with control. Their molecular functions were further screened for transmembrane ion transporter, calcium or zinc ion binder. Among these, 11 candidate proteins were shortlisted in NaOx diet and 16 proteins in EG diet. We concluded that GASP is a proteomic sample preparation method that can be applied to individual Drosophila Malpighian tubules. Our results may further increase the understanding of the pathophysiology of human kidney stone disease. 相似文献