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61.
62.
B.A. Naaijkens A. van Dijk E. Meinster K. Kramer O. Kamp P.A.J. Krijnen H.W.M. Niessen L.J.M. Juffermans 《Research in veterinary science》2014
The Wistar rat is a commonly used strain for experimental animal models. Recently it was shown that results vary between studies using Wistar rats of different suppliers. Therefore we studied whether Wistar rats obtained from Harlan Laboratories (Ha, n = 24) and Charles River (CR, n = 22) had a different outcome in an acute myocardial infarction (AMI) model. AMI was induced in both Ha and CR Wistar rats by one operator. This resulted in a significantly higher survival rate for Ha (79.2 ± 10.2%) compared with CR rats (54.2 ± 10.2%, p < 0.05). Furthermore, CR rats had lost significantly more weight after 7 days (−5.9 ± 3.1%) compared with Ha rats (−0.8 ± 1.7%; p < 0.001), indicating a worse health status of the CR rats. Paradoxically, the induced infarct was smaller in CR rats (7.3 ± 3.6% of the heart) compared with Ha rats (12.1 ± 4.7%, p < 0.05). This indicates that CR rats were less sensitive for the cardiomyocyte damage subsequent to AMI induction, but remarkably showed more clinical side effects indicating that Wistar rats from two suppliers had a different response within the same AMI model. 相似文献
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64.
Evidence is presented for a novel mechanism mediating the auditory sense in the Choerocampinae (Lepidoptera: Sphingidae). Vibrations in the scale-free medial wall of the enlarged labial palp segment are transmitted by contact to the distal lobe of the pilifer, a derivative of the labrum, and are there transduced into afferent impulses in the labral nerve. 相似文献
65.
Sebat J Lakshmi B Malhotra D Troge J Lese-Martin C Walsh T Yamrom B Yoon S Krasnitz A Kendall J Leotta A Pai D Zhang R Lee YH Hicks J Spence SJ Lee AT Puura K Lehtimäki T Ledbetter D Gregersen PK Bregman J Sutcliffe JS Jobanputra V Chung W Warburton D King MC Skuse D Geschwind DH Gilliam TC Ye K Wigler M 《Science (New York, N.Y.)》2007,316(5823):445-449
We tested the hypothesis that de novo copy number variation (CNV) is associated with autism spectrum disorders (ASDs). We performed comparative genomic hybridization (CGH) on the genomic DNA of patients and unaffected subjects to detect copy number variants not present in their respective parents. Candidate genomic regions were validated by higher-resolution CGH, paternity testing, cytogenetics, fluorescence in situ hybridization, and microsatellite genotyping. Confirmed de novo CNVs were significantly associated with autism (P = 0.0005). Such CNVs were identified in 12 out of 118 (10%) of patients with sporadic autism, in 2 out of 77 (3%) of patients with an affected first-degree relative, and in 2 out of 196 (1%) of controls. Most de novo CNVs were smaller than microscopic resolution. Affected genomic regions were highly heterogeneous and included mutations of single genes. These findings establish de novo germline mutation as a more significant risk factor for ASD than previously recognized. 相似文献
66.
Determining an optimal mesh size for use in the lampara net fishery for eastern sea garfish, Hyporhamphus australis 总被引:1,自引:0,他引:1
J. Stewart C. Walsh D. Reynolds B. Kendall & C. Gray 《Fisheries Management and Ecology》2004,11(6):403-410
Abstract The selection properties of three experimental mesh sizes were examined in the lampara net fishery for eastern sea garfish, Hyporhamphus australis (Steindachner), in New South Wales, Australia. The sizes of fish retained in 25-, 28- and 32-mm mesh nets were compared with those retained in a control 12-mm mesh net. The 25-mm mesh net retained significant numbers of immature H. australis , the 28-mm mesh net retained predominantly only mature fish and the 32-mm mesh had very low catch rates. Catch rates decreased linearly with increasing mesh size and there was a significant linear relationship between mesh size and the 50% selection size ( L 50 ). Given this species is being overfished, the 28-mm mesh size is recommended as the most appropriate for use in the fishery. 相似文献
67.
Three experiments were conducted to determine the optimum standardized ileal digestible Val-to-Lys (SID Val:Lys) ratio for 13- to 32-kg pigs. In Exp. 1, 162 pigs weaned at 17 d of age (8 pens/treatment) were used, and a Val-deficient basal diet containing 0.60% l-Lys·HCl, 1.21% SID Lys, and 0.68% SID Val was developed (0.56 SID Val:Lys). Performance of pigs fed the basal diet was inferior to a corn-soybean meal control containing only 0.06% l-Lys·HCl, but was fully restored with the addition of 0.146% l-Val to the basal diet (68% SID Val:Lys). In Exp. 2, 54 individually housed barrows (21.4 kg) were utilized in a 14-d growth assay. Pigs were offered a similar basal diet (1.10% SID Lys), ensuring Lys was marginally limiting with no supplemental l-Val (55% SID Val:Lys). The basal diet was fortified with 4 graded levels of l-Val (0.055% increments) up to a ratio of 75% SID Val:Lys. In Exp. 3, 147 barrows (13.5 kg) were fed identical diets, only with 1 additional level at a SID Val:Lys of 80% and fed for 21 d. In Exp. 2 and 3, a high protein, control diet was formulated to contain 1.10% SID Lys and 0.20% l-Lys·HCl. In Exp. 2, linear effects on ADG (713, 750, 800, 796, and 785 g/d; P = 0.05) and G:F (P = 0.07) were observed with increasing SID Val:Lys, characterized by improvements to a ratio of 65% and a plateau thereafter. In Exp. 3, quadratic improvements in ADG (600, 629, 652, 641, 630, and 642 g/d; P = 0.08) and G:F (P = 0.07) were observed with increasing SID Val:Lys, as performance increased to a ratio of 65% but no further improvement to a ratio of 80%. Pigs fed the control diet did not differ from those fed a ratio of 65% SID Val:Lys in Exp. 2, but did have improved G:F in Exp. 3 (P = 0.03). To provide a more accurate estimate of the optimum SID Val:Lys, data from Exp. 2 and 3 were combined. With single-slope broken-line methodology, the minimum ratio estimate was 64 and 65% SID Val:Lys for ADG and G:F, respectively. With combined requirement estimates, the data indicate that a SID Val:Lys of 65% seems adequate in maintaining performance for pigs from 13 to 32 kg. 相似文献
68.
This study aimed to determine values for selected energy metabolites (non-esterified fatty acid [NEFA], β-hydroxybutyrate [BHB], urea or urea:BHB ratio), together with a body condition score, associated with an increased risk of cows developing a reproductive disorder and to investigate temporal relationships between predictors and reproductive outcome. A cohort of 98 cows on one farm was monitored weekly from four weeks before to 10 weeks after calving; 89 cows provided sufficient data to calculate commencement of luteal activity (C-LA). Cows with high NEFA × urea (Nu; product of NEFA and urea) values one and three weeks after calving were twice as likely to develop cystic ovarian disease (risk ratio 2). Cows that developed endometritis had high NEFA values one (P=0.02) or four weeks (P=0.04) before calving, or low urea:BHB ratios two weeks before calving, at calving or three weeks after calving (P=0.024, P=0.031 and P=0.001, respectively). Cows that had delayed C-LA had high NEFA values one week after calving (P=0.05) or low urea:BHB ratios three or four weeks after calving (P=0.004 and P=0.003, respectively). 相似文献
69.
To establish the role of the dermonecrotic toxin (DNT) of Pasteurella multocida in the cause and pathogenesis of atrophic rhinitis, germ-free pigs were inoculated with several strains of P multocida, crude DNT, or purified DNT. In some experiments, the aforementioned inocula were combined with Bordetella bronchiseptica. All DNT-producing P multocida strains induced severe turbinate atrophy. Histologic examination of the remnants of the nasal turbinates revealed intact, but undulated, ciliated epithelium and numerous osteoclasts. Inflammation was minimal or absent. A DNT-producing B bronchiseptica strain induced only mild turbinate atrophy. The lesions were characterized histologically by loss of cilia and ciliated cells and by an infiltration of predominantly mononuclear cells. Bone formation seemed impaired. Turbinate lesions were most severe in pigs infected with a combination of B bronchiseptica and a DNT-producing P multocida strain. Intranasal administration of sterile DNT-containing culture filtrate of P multocida or purified DNT of P multocida did not result in turbinate atrophy. In contrast, turbinate atrophy developed when these preparations were injected IM or when intranasal administration of DNT was preceded by inoculation of B bronchiseptica. 相似文献
70.
S B Kendall 《The Veterinary record》1974,95(17):388-390