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951.
Natural antibodies are an important component of innate humoral immunity but have not been investigated to any great extent in wild mammals. In the current study, serum natural antibody titres were measured by hemagglutination assay for two South American herbivores, the guanaco (Lama guanicoe) and the capybara (Hydrochoerus hydrochaeris). Results indicated that capybaras had antibody titres on average more than four times higher than guanacos (median titres 1:256 and 1:4, respectively), suggesting differences in investment in constitutive humoral immunity between the two species.  相似文献   
952.
This report describes a 2-year-old collie dog with pulmonary nodules, visualized by computed tomographic (CT) scan, with evidence of Bartonella henselae bacteremia and pyogranulomatous lymphadenitis. Clinical signs resolved with antimicrobial therapy.  相似文献   
953.
Aim of this study was to characterize the effects of an ochratoxin A (181 ± 34 ng/g) contaminated diet on growth performances, blood parameters, systemic cytokine levels, cell stress markers and reactivity of immune system of weaned pigs.  相似文献   
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Xylella fastidiosa (Xf) is a gram-negative bacterial plant pathogen that can infect over 500 plant species. While it is endemic in America, X. fastidiosa subsp. pauca was reported for the first time in Europe in 2013 on olive trees in southern Italy. The availability of fast, sensitive, and reliable diagnostic tools is indispensable for managing current and future outbreaks of Xf. In this paper, we use the OXford Nanopore Technologies (ONT) MinION platform for detecting and identifying Xf at species, subspecies, and sequence type (ST) level. Two workflows were developed: the first one provided a “shotgun” strategy, that is, exploring the possibility of detecting Xf within DNA extracted from plant samples. This allowed detection of Xf by direct DNA sequencing and identifying the subspecies only in samples with high bacterial levels. Nanopore amplicon sequencing was pursued as a second workflow. This consists of PCR amplification of a set of seven multilocus sequence typing (MLST) fragments, officially adopted for identifying Xf at type strain level, followed by Nanopore-sequencing of the amplicons and an ad hoc pipeline to generate MLST consensus calls. This combined approach, which takes only a few hours, allowed the detection and identification of Xf at ST level in plant material with low bacterial infection.  相似文献   
957.
This study aimed to prepare anovulatory mares in anestrus or in the transitional period as embryo recipients. Ninety embryo-recipient mares were divided into two groups (G). G1 (n = 45) comprised animals in anestrus or in the transitional period; these animals were treated for 3 days (D) with 5, 3, and 2 mg of estradiol benzoate (intramuscular) on D0 (day of the donor's ovulation), D1, and D2 (after ovulation), respectively, followed by weekly application of 400 mg of long-acting progesterone (intramuscular) from D3 after ovulation (donor) until the 120th day of gestation. G2 (n = 45) comprised mares with normal estrous cycles. Plasma levels of progesterone (P4) were measured on days D1, D2, D8, and D14. Sixty percent of the animals in G1 and 71.1% in G2 (P > .05) completed the pregnancy. On D8, there was no difference in P4 levels between G1 and G2 animals, but there was a difference in P4 levels on D14 (P < .05). It was concluded that anovulatory mares in anestrus or in the transitional period could be used as embryo recipients. The protocol was efficient and also considered an appropriate alternative to prepare the uterine environment for embryo transfer; long-acting progesterone administration kept P4 levels high enough to maintain pregnancy until the 120th day and provided recipients during the time of the year when fewer mares were cycling and ovulating.  相似文献   
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A detailed examination of a unique molecular family, restricted to the Callyspongia genus, in a molecular network obtained from an in-house Haplosclerida marine sponge collection (including Haliclona, Callyspongia, Xestospongia, and Petrosia species) led to the discovery of subarmigerides, a series of rare linear peptides from Callyspongia subarmigera, a genus mainly known for polyacetylenes and lipids. The structure of the sole isolated peptide, subarmigeride A (1) was elucidated through extensive 1D and 2D NMR spectroscopy, HRMS/MS, and Marfey’s method to assign its absolute configuration. The putative structures of seven additional linear peptides were proposed by an analysis of their respective MS/MS spectra and a comparison of their fragmentation patterns with the heptapeptide 1. Surprisingly, several structurally related analogues of subarmigeride A (1) occurred in one distinct cluster from the molecular network of the cyanobacteria strains of the Guadeloupe mangroves, suggesting that the true producer of this peptide family might be the microbial sponge-associated community, i.e., the sponge-associated cyanobacteria.  相似文献   
960.
一个由北京基因组研究所领导的国际研究团队使用重测序构建了家蚕遗传变异图谱,研究结果为阐明生物的驯化提供了线索。今天的Science杂志在线报道了这项工作。  相似文献   
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