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71.
Length–weight and length–length relationships of 139 Indo‐Pacific fish species (Teleostei) from the Davao Gulf,Philippines 下载免费PDF全文
G. S. Gumanao M. M. Saceda‐Cardoza B. Mueller A. R. Bos 《Zeitschrift fur angewandte Ichthyologie》2016,32(2):377-385
Length–weight relationships (LWRs) of 139 coral reef and pelagic fish species (representing 34 fish families) were calculated based on 3806 individuals measured at local fish markets near the Davao Gulf in the southern Philippines during weekly visits between March 2009 and July 2011, as well as in June 2012. Fishes were caught with a variety of fishing methods, corroborated by abrasions and injuries. Forty‐seven of 139 LWRs were firstly reported and new to science. The mean slope b of the LWRs was 3.035, indicating that the majority of studied species followed isometric growth. Standard length – total length relationships were calculated for all measured fish species. Additionally, standard length – fork length relationships are presented for 108 species. Moreover, fifteen new records of maximum fish length and weight are reported. 相似文献
72.
Aim
To highlight gender-related differences in octogenarians with a congenital coronary artery fistula (CAF).Materials and methods
We present two elderly female patients with a congenital fistula, a septuagenarian and a nonagenarian, and review the world literature between 1954–2010.Results
The septuagenarian patient presented with easy fatigability and the nonagenarian patient with acute myocardial infarction contralaterally to the fistula. Coronary angiography (CAG) demonstrated a coronary-pulmonary artery fistula (CPF). The nonagenarian patient underwent percutaneous coronary intervention of the right coronary artery. CAG revealed a CPF associated with a huge multiple aneurysmal formation. Data from 57 mainly symptomatic patients with a mean age of 75.3 years (range 70–87 years) were collected. The cohort was subdivided into female (mean age 84.3 years) and male (mean age 75.2 years) subgroups and compared with each other. Multi-origin (bilateral and multilateral) was prevalent in females, 40% versus 12% in males. Aneurysmal formation was found in females and males in 40% and 18%, respectively. Ethnicity was 65% Caucasian and 35% Asian. Multi-origin fistulas were prevalent in the Asian (45%) compared with the Caucasian (11%) subset.Conclusions
A septuagenarian and a nonagenarian female patient with congenital CAF are presented. On reviewing the literature, important differences were found between elderly females and males with congenital CAF. 相似文献73.
Abstract. Vegetation succession in three back‐barrier salt marshes in the Wadden Sea was studied using a data set comprising 25 years of vegetation development recorded at permanent quadrats. The effect of livestock grazing on succession was assessed by comparing quadrats where grazing was experimentally prevented or imposed. We studied changes at the species level as well as at the level of the plant community. Special attention is given to effects on plant species richness and community characteristics that are relevant for lagomorphs (hares and rabbits) and geese. Inundation frequency and grazing were most important in explaining the variation in species abundance data. The three marshes studied overlap in the occurrence of different plant communities and the observed patterns were consistent between them. Clear differences in frequency and abundance of plant species were observed related to grazing. Most plant species had a greater incidence in grazed treatments. Species richness increased with elevation, and was 1.5 to 2 × higher in the grazed salt marsh. Grazing negatively influenced Atriplex portulacoides and Elymus athericus, whereas Puccinellia maritima and Festuca rubra showed a positive response. The communities dominated by Elymus athericus, Artemisia maritima and Atriplex portulacoides were restricted to the ungrazed marsh. Communities dominated by Puccinellia maritima, Juncus gerardi and Festuca rubra predominantly occurred at grazed sites. As small vertebrate herbivores prefer these plants and communities for foraging, livestock grazing thus facilitates for them. 相似文献
74.
de Bruyn KM Zwartkruis FJ de Rooij J Akkerman JW Bos JL 《The Journal of biological chemistry》2003,278(25):22412-22417
The small GTPase Rap1, which is activated by a large variety of stimuli, functions in the control of integrin-mediated cell adhesion. Here we show that in human megakaryocytes and several other commonly used hematopoietic cell lines such as K562, Jurkat, and THP-1, stress induced by gentle tumbling of the samples resulted in rapid and strong activation of Rap1. This turbulence-induced activation could not be blocked by inhibitors previously shown to affect Rap1 activation in human platelets, such as the intracellular calcium chelator BAPTA-AM (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid) and various protein kinase C inhibitors. Also inhibition of actin cytoskeleton dynamics did not influence this activation of Rap1, suggesting that this activation is mediated by cell surface receptors. Human platelets, however, were refractory to turbulence-induced activation of Rap1. To determine the consequences of Rap1 activation we measured adhesion of megakaryocytes to fibrinogen, which is mediated by the integrin alphaIIbbeta3, in the presence of inhibitors of Rap1 signaling. Introduction of both Rap1GAP and RalGDS-RBD in the megakaryoblastic cell line DAMI strongly reduced basal adhesion to immobilized fibrinogen. This inhibition was partially rescued by the phorbol ester 12-O-tetradecanoylphorbol-13-acetate but not by alpha-thrombin. From these results we conclude that in megakaryocytes turbulence induces Rap1 activation that controls alphaIIbbeta3-mediated cell adhesion. 相似文献
75.
Inferring population history and demography using microsatellites, mitochondrial DNA, and major histocompatibility complex (MHC) genes 总被引:4,自引:0,他引:4
Bos DH Gopurenko D Williams RN Dewoody JA 《Evolution; international journal of organic evolution》2008,62(6):1458-1468
Microsatellites and mitochondrial DNA (mtDNA) have traditionally been used in population genetics because of their variability and presumed neutrality, whereas genes of the major histocompatibility complex (MHC) are increasingly of interest because strong selective pressures shape their standing variation. Despite the potential for MHC genes, microsatellites, and mtDNA sequences to complement one another in deciphering population history and demography, the three are rarely used in tandem. Here we report on MHC, microsatellite, and mtDNA variability in a single large population of the eastern tiger salamander (Ambystoma tigrinum tigrinum). We use the mtDNA mismatch distribution and, on microsatellite data, the imbalance index and bottleneck tests to infer aspects of population history and demography. Haplotype and allelic variation was high at all loci surveyed, and heterozygosity was high at the nuclear loci. We find concordance among neutral molecular markers that suggests our study population originated from post-Pleistocene expansions of multiple, fragmented sources that shared few migrants. Differences in N(e) estimates derived from haploid and diploid genetic markers are potentially attributable to secondary contact among source populations that experienced rapid mtDNA divergence and comparatively low levels of nuclear DNA divergence. We find strong evidence of natural selection acting on MHC genes and estimate long-term effective population sizes (N(e)) that are very large, making small selection intensities significant evolutionary forces in this population. 相似文献
76.
J A van de Wiel C M Duijf J C Pertijs J H Copius Peereboom-Stegeman R P Bos 《Laboratory animals》1990,24(3):265-272
Ethanol was administered to female and male Wistar rats by mixing it with their drinking water. Ethanol concentrations were gradually increased up to either 8% or 15%. Female rats receiving 8% ethanol in their drinking water consumed 5-13 g, males 4-10 g daily. The ethanol/total food caloric intake percentages were 13 to 20% and 9 to 15% for female and male rats, respectively. There was no difference in body weight and relative liver weight between treated rats and their controls. Female and male rats receiving 15% of ethanol in their drinking water consumed 8-14 g ethanol per kg body weight per day. The percentages of ethanol/total food caloric intake were stabilized at about 25% for both sexes. Growth of the rats differed only slightly from controls; a tendency for a higher increase of body weight of the control rats was found. No difference in relative liver weight between ethanol-treated and control rats was observed. Microscopic examinations revealed that the ethanol treatment resulted in fat accumulation in the liver cells. A proliferation of the Smooth Endoplasmic Reticulum (SER) was more marked in the 15% dosed rats than in the 8% dosed rats and more distinct in female rats than in male rats in both dosage groups. 相似文献
77.
A functional genomics approach identifies candidate effectors from the aphid species Myzus persicae (green peach aphid) 总被引:2,自引:0,他引:2
Aphids are amongst the most devastating sap-feeding insects of plants. Like most plant parasites, aphids require intimate associations with their host plants to gain access to nutrients. Aphid feeding induces responses such as clogging of phloem sieve elements and callose formation, which are suppressed by unknown molecules, probably proteins, in aphid saliva. Therefore, it is likely that aphids, like plant pathogens, deliver proteins (effectors) inside their hosts to modulate host cell processes, suppress plant defenses, and promote infestation. We exploited publicly available aphid salivary gland expressed sequence tags (ESTs) to apply a functional genomics approach for identification of candidate effectors from Myzus persicae (green peach aphid), based on common features of plant pathogen effectors. A total of 48 effector candidates were identified, cloned, and subjected to transient overexpression in Nicotiana benthamiana to assay for elicitation of a phenotype, suppression of the Pathogen-Associated Molecular Pattern (PAMP)-mediated oxidative burst, and effects on aphid reproductive performance. We identified one candidate effector, Mp10, which specifically induced chlorosis and local cell death in N. benthamiana and conferred avirulence to recombinant Potato virus X (PVX) expressing Mp10, PVX-Mp10, in N. tabacum, indicating that this protein may trigger plant defenses. The ubiquitin-ligase associated protein SGT1 was required for the Mp10-mediated chlorosis response in N. benthamiana. Mp10 also suppressed the oxidative burst induced by flg22, but not by chitin. Aphid fecundity assays revealed that in planta overexpression of Mp10 and Mp42 reduced aphid fecundity, whereas another effector candidate, MpC002, enhanced aphid fecundity. Thus, these results suggest that, although Mp10 suppresses flg22-triggered immunity, it triggers a defense response, resulting in an overall decrease in aphid performance in the fecundity assays. Overall, we identified aphid salivary proteins that share features with plant pathogen effectors and therefore may function as aphid effectors by perturbing host cellular processes. 相似文献
78.
Meerding WJ Doornewaard H van Ballegooijen M Bos A van der Graaf Y van den Tweel JG van der Schouw YT Habbema JD 《Acta cytologica》2001,45(1):28-35
OBJECTIVE: To assess the difference in costs between PAPNET-assisted and conventional microscopy of cervical smears when used as a primary screening tool. STUDY DESIGN: We performed time measurements of the initial screening of smears by four cytotechnologists in one laboratory. Time was measured in 816 conventionally screened smears and in 614 smears with PAPNET-assisted screening. Data were collected on the components of initial screening, clerical activities and other activities in the total work time of cytotechnologists in the routine situation and on resource requirements for both techniques. RESULTS: PAPNET saved an average of 22% on initial screening time per smear. Due to costs of processing and additional equipment, the costs of PAPNET-assisted screening were estimated to be $2.85 (and at least $1.79) higher per smear than conventional microscopy. The difference in costs is sensitive to the rate of time saving, the possibility of saving on quality control procedures and the component of the initial screening time in the total work time of cytotechnologists. CONCLUSION: Although PAPNET is time saving as compared with conventional microscopy, the associated reduction in personnel costs is outweighed by the costs of scanning the slides and additional equipment. This conclusion holds under a variety of assumptions. Using PAPNET instead of conventional microscopy as a primary screening tool will make cervical cancer screening less cost-effective unless the costs of PAPNET are considerably reduced and its sensitivity and/or specificity are considerably improved. 相似文献
79.
Van Eck M Hoekstra M Out R Bos IS Kruijt JK Hildebrand RB Van Berkel TJ 《Journal of lipid research》2008,49(1):136-146
Scavenger receptor class B type I (SR-BI) functions as an HDL receptor that promotes the selective uptake of cholesteryl esters (CEs). The physiological role of SR-BI in VLDL metabolism, however, is largely unknown. SR-BI deficiency resulted in elevated VLDL cholesterol levels, both on chow diet and upon challenge with high-cholesterol diets. To specifically elucidate the role of SR-BI in VLDL metabolism, the plasma clearance and hepatic uptake of (125)I-beta-VLDL were studied in SR-BI(+/+) and SR-BI(-/-) mice. At 20 min after injection, 66 +/- 2% of the injected dose was taken up by the liver in SR-BI(+/+) mice, as compared with only 22 +/- 4% (P = 0.0007) in SR-BI(-/-) mice. In vitro studies established that the B(max) of (125)I-beta-VLDL binding was reduced from 469 +/- 30 ng/mg in SR-BI(+/+) hepatocytes to 305 +/- 20 ng/mg (P = 0.01) in SR-BI(-/-) hepatocytes. Both in vivo and in vitro, limited to no selective uptake of CEs from beta-VLDL was found. Interestingly, HDL effectively competed for the association of beta-VLDL in the presence as well as in the absence of SR-BI, indicating a second common recognition site. In conclusion, SR-BI plays an important physiological role in the metabolism of VLDL (remnants). 相似文献
80.
Carboxylesterase NP of Bacillus subtilis Thai I-8, characterized in 1992 as a very enantioselective (S)-naproxen esterase, was found to show no enantiopreference towards (S)-1,2-O-isopropylideneglycerol (IPG) esters. The ybfK gene was identified by the B. subtilis genome project as an unknown gene with homology to carboxylesterase NP. The purpose of the present study was to characterize the ybfK gene product in order to determine whether this paralogue of carboxylesterase NP had an altered or enhanced stereospecificity. The ybfK gene was cloned and expressed in B. subtilis using a combination of two strong promoters in a multicopy vector. The enzyme was purified from the cytoplasm of B. subtilis by means of anion exchange and hydrophobic interaction chromatography. The purified YbfK is an enzyme of 296 amino acids and shows an apparent molecular mass of 32 kDa (SDS/PAGE). Comparison of the activities of YbfK and carboxylesterase NP towards caprylate esters of IPG revealed that YbfK produces (S)-IPG with 99.9% enantioselectivity. Therefore, we conclude that we have isolated a paralogue of carboxylesterase NP that can be used for the enantioselective production of (S)-IPG. 相似文献