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1.
In this study, adaptive immune response was investigated in farmed southern bluefin tuna, Thunnus maccoyii, infected with a sanguinicolid Cardicola forsteri. A cohort (Cohort2005) of southern bluefin tuna was sampled between March 2005 and August 2006. Samples were taken at the transfer of wild caught tuna to sea cages and then at regular intervals. Parasite intensity, abundance and prevalence data were recorded. An ELISA was developed to detect and quantify an antibody response against the blood fluke in southern bluefin tuna serum. Intensity and prevalence of the blood fluke were shown to peak in May 2005 at 10.9 flukes per infected fish (SE = 1.72) and 97.5% prevalence and then decreased to low prevalence (10%) and intensity (1.0). There were no significant changes in prevalence or intensity in 2006. Antibody titres and seroprevalence increased from 1.37 U μl−1 and 10% at transfer in March 2005 to reach a peak in December 2005 of 25.86 U μl−1 (SE = 6.26 U μl−1) and 66.66%. No significant changes were observed in antibody titres for the same cohort of fish during 2006. Parasitological and serological values from Cohort2005 were compared to a 2006 cohort (Cohort2006) in March 2006 and August 2006 to determine if prior infection in Cohort2005 elicited any protection against infection in 2006. Although significant differences were not observed in intensities between cohorts it was shown that Cohort2005 had significantly lower abundances and prevalences of blood fluke infection than Cohort2006. Although there was no significant difference in mean antibody titres between cohorts in March 2006, the mean antibody titre of Cohort2006 was significantly greater than that of Cohort2005 in August 2006. No significant differences were observed in seroprevalence. This is one of the few studies to demonstrate the development of acquired resistance in fish against a parasite in an aquaculture environment under natural infection conditions.  相似文献   

2.
3.
Citation advantage of open access articles   总被引:9,自引:0,他引:9       下载免费PDF全文
Open access (OA) to the research literature has the potential to accelerate recognition and dissemination of research findings, but its actual effects are controversial. This was a longitudinal bibliometric analysis of a cohort of OA and non-OA articles published between June 8, 2004, and December 20, 2004, in the same journal (PNAS: Proceedings of the National Academy of Sciences). Article characteristics were extracted, and citation data were compared between the two groups at three different points in time: at “quasi-baseline” (December 2004, 0–6 mo after publication), in April 2005 (4–10 mo after publication), and in October 2005 (10–16 mo after publication). Potentially confounding variables, including number of authors, authors' lifetime publication count and impact, submission track, country of corresponding author, funding organization, and discipline, were adjusted for in logistic and linear multiple regression models. A total of 1,492 original research articles were analyzed: 212 (14.2% of all articles) were OA articles paid by the author, and 1,280 (85.8%) were non-OA articles. In April 2005 (mean 206 d after publication), 627 (49.0%) of the non-OA articles versus 78 (36.8%) of the OA articles were not cited (relative risk = 1.3 [95% Confidence Interval: 1.1–1.6]; p = 0.001). 6 mo later (mean 288 d after publication), non-OA articles were still more likely to be uncited (non-OA: 172 [13.6%], OA: 11 [5.2%]; relative risk = 2.6 [1.4–4.7]; p < 0.001). The average number of citations of OA articles was higher compared to non-OA articles (April 2005: 1.5 [SD = 2.5] versus 1.2 [SD = 2.0]; Z = 3.123; p = 0.002; October 2005: 6.4 [SD = 10.4] versus 4.5 [SD = 4.9]; Z = 4.058; p < 0.001). In a logistic regression model, controlling for potential confounders, OA articles compared to non-OA articles remained twice as likely to be cited (odds ratio = 2.1 [1.5–2.9]) in the first 4–10 mo after publication (April 2005), with the odds ratio increasing to 2.9 (1.5–5.5) 10–16 mo after publication (October 2005). Articles published as an immediate OA article on the journal site have higher impact than self-archived or otherwise openly accessible OA articles. We found strong evidence that, even in a journal that is widely available in research libraries, OA articles are more immediately recognized and cited by peers than non-OA articles published in the same journal. OA is likely to benefit science by accelerating dissemination and uptake of research findings.  相似文献   

4.
A nationwide hepatitis B virus (HBV) vaccination program was implemented in China starting in 1992. To study the change in HBV variant prevalence with massive immunization, large HBV surface protein (LHBs) genes from HBV surface antigen (HBsAg)-positive sera were amplified and sequenced. The prevalences of LHBs mutants were compared between the 1992 and 2005 surveys in child and adult groups. The prevalence of “α” determinant mutants in the children increased from 6.5% in 1992 to 14.8% in 2005, where the G145R mutant occurred most frequently. In contrast, mutation frequencies showed little difference between 1992 (9.4%) and 2005 (9.9%) in adults. Moreover, compared to the 1992 survey, the child group surface (S) protein mutation frequency specifically increased (P = 0.005) in the 2005 survey, but the pre-S region mutation frequency did not show a significant difference (P > 0.05). However, the mutation frequency in the adult group increased in both the pre-S and S regions. Furthermore, the frequencies of the disease-related pre-S2 deletion and start codon mutations were significantly higher in the adult groups than in the child groups in both the 1992 and 2005 surveys (P < 0.01). Massive immunization enhances the HBV S protein mutation; the prevalence of LHBs mutants, particularly disease-related mutants, tends to increase with patient age.  相似文献   

5.
The nutrition conditions needed to redirect the carbon flux in Torulopsis glabrata, a pyruvate hyper-production yeast, from pyruvate to α-ketoglutaric acid (KG) were investigated in a stirred fermentor. A minor amount of KG (1.3 gl−1) was produced when NaOH was used to control the pH, while 12 g KG l−1 was produced when CaCO3 was used instead. When thiamine and biotin were included in the medium, 13 g KG l−1 and 68 g pyruvate l−1 were produced after 48 h when glucose was nearly consumed (approximately 5 gl−1). With fermentation continuing for a further 16 h, the concentration of pyruvate decreased to 31 gl−1, and KG increased to 30 gl−1. KG thus accumulated at the expense of pyruvate consumption. Received 2 June 2005; Revisions requested 30 June 2005 and 1 September 2005; Revisions received 1 September 2005 and 28 October 2005; Accepted 28 October 2005  相似文献   

6.
Lipopolysaccharide (LPS)-binding peptides were enriched by using epoxy beads as a novel support to immobilize LPS for a phage displayed peptide library screening. The sequence of Phe-Ala-Pro-Trp (FAPW) was the most significant consensus motif of 10 selected clones, and Pro-Phe (PF) was the key dipeptide for binding at the apex of the loop to form a characteristic structure of CXXPFXXXC. Moreover, AWLPWAK, one of the highly conserved heptamer peptides, could detect specifically Gram-negative bacteria via a whole cell binding test at 106 cells ml−1. Received 12 July 2005; Revisions requested 1 August 2005 and 26 September 2005; Revisions received 12 September 2005 and 25 October 2005; Accepted 1 November 2005  相似文献   

7.
Declining reproductive performance is a serious breeding concern in many countries. To reveal the situation in Norwegian cattle, trends in reproductive performance were studied using insemination reports from 1985 to 2005 and data based on herd recording files from 1989 to 2005. The total number of first services was 469.765 in 1985 declining to 335.712 in 2005. The number of recorded herds and animals declined from 21.588 to 14.718 and 360.289 to 309.452 from 1989 to 2005, respectively. Sixty days non-return rate after single inseminations (NR60) increased from 68.1 in 1985 to 72.7% in 2005 (p < 0.001) and the number of services per inseminated animal (NIA) decreased from 1.8 to 1.6 (p < 0.001) from 1985 to 2005. However, return rates 0–3 days post insemination (RR0-3) increased from 6 to 12% in the same period (p < 0.001). NR60 was higher and the RR0-3 was lower in the summer season compared to the winter season during the whole period. A fertility index (FS), has been calculated from the herd recording files each year from 1989 to 2005. The average FS-index did not show a significant trend and the calving interval was also fairly constant between 12.4 and 12.6 months during this period. The average interval from calving to first and last insemination, respectively, increased from a low of 79 and 102 days in 1990 to a high of 86 and 108 days in 2005. Both intervals were consistently longer for cows in first lactation than for cows in later lactations. The percentage of inseminated animals reported culled because of poor fertility decreased from 6.0% in 1989 to 4.6% in 1996 and thereafter again increased to 6% in 2005. In conclusion, most fertility measures, mainly comprising the Norwegian Red (NRF) breed, show a relatively high level of reproductive performance with a positive or a relatively constant trend during the last two decades.  相似文献   

8.
Responses of the heart rate variability (HRV) and fractal neurodynamics (FND) to local magnetic vibroacoustic treatment were statistically estimated. The HRV and FND were dependent both on local physiotherapy and on the period of treatment.__________Translated from Fiziologiya Cheloveka, Vol. 31, No. 4, 2005, pp. 50–60.Original Russian Text Copyright © 2005 by Byalovskii, Bulatetskii, Suchkova.  相似文献   

9.
Suspension culture of gametophytes of transgenic kelp in a photobioreactor   总被引:5,自引:0,他引:5  
Gao J  Zhang Y  Wang H  Qin S 《Biotechnology letters》2005,27(14):1025-1028
Transgenic Laminaria japonica gametophytes producing a recombinant tissue-type plasminogen activator (rtPA) protein, which is an effective third-generation thrombolytic agent for acute myocardial infarction (AMI), were cultured in an illuminated bubble column bioreactor. A maximum final dry cell weight of 1120 mg l−1 was obtained in batch culture with an initial dry cell weight of 126 mg l−1 and with aeration rate of 1.2 l air min−1 l−1 culture, nitrate at 1.5 mM and phosphate at 0.17 mM. The yield of rtPA was 56 μg g−1 dry cell wt. This is the first report regarding cultivation of a transgenic macroalga in a bioreactor.Revisions requested 27 January 2005 and 14 April 2005; Revisions received 6 April 2005 and 17 May 2005  相似文献   

10.
New polymethylene nucleoside analogues with a β-dioxo function in the ω-position of their hydro-carbon chain, [7-(2-oxocyclohexyl)-7-oxoheptyl]purines, were synthesized, and their physicochemical properties were studied.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 3, 2005, pp. 288–294.Original Russian Text Copyright © 2005 by Kritzyn, Vepsalainen, Komissarov.For communication III, see [1].  相似文献   

11.
The chemotactic responses of Bacillus thuringiensis subsp. dendrolimus (strain 49) and thuringiensis (strain 2002) and their morphological dissociants were studied by using some natural and artificial substances as effectors. The 12-h-old wild-type cells (S variants) of both strains were found to be motile and similar in their chemotactic responses, whereas the chemotactic responses of the R variants were different.Translated from Mikrobiologiya, Vol. 74, No. 1, 2005, pp. 87–91.Original Russian Text Copyright © 2005 by Lebenko, Sekerina, Chemerilova.  相似文献   

12.
Salmonella were isolated from black-headed gulls (Larus ridibundus) in six locations in the Czech Republic from 1984 to 2005 (Chropyně and Nymburk in 1984–1986; Nové Mlyny, Bartošovice, and Hodonín in 1991–1994; and Nové Mlyny, Bartošovice, and Ostrava in 2005). Antimicrobial susceptibility was determined in 12 antimicrobial drugs using disk diffusion. Although 95% of Salmonella isolates (197 out of 207) were pansusceptible, the prevalences of resistance increased significantly from 1 (2%) out of 59 isolates in 1984–1986 and 3 (3%) out of 100 isolates in 1991–1994 to 6 (13%) out of 48 isolates in 2005. Furthermore, in 2005, two isolates were nalidixic acid-resistant and one isolate was multidrug-resistant Salmonella Typhimurium DT 104. These findings suggest that the occurrence of salmonellae in black-headed gulls depends to a large extent on the contamination where the gulls feed and possibly reflects the dissemination of these strains among farm animals and humans. Black-headed gulls may also become infected with resistant Salmonella and thus pose a potential risk of Salmonella contamination of surface water and animal feeds, and consequently dissemination.  相似文献   

13.
Theoretical conformational analysis was used to study the spatial structure and conformational properties of myelopeptides, bone-marrow peptide mediators. The low-energy conformations of myelopeptides MP-4 (Phe-Arg-Pro-Arg-Ile-Met-Thr-Pro), MP-5 (Val-Val-Tyr-Pro-Asp), and MP-6 (Val-Asp-Pro-Pro) were found; the values of dihedral angles of backbone and side chains of the amino acid residues were determined; and the energies of intra- and interresidual interactions were estimated.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 2, 2005, pp. 140–146.Original Russian Text Copyright © 2005 by Ismailova, Akhmedov, Abbasli, Godjaev.  相似文献   

14.
Racemic diisophorone (500 mg) was converted by Cephalosporium aphidicola and Neurospora crassa over 10 days at 25 °C to 8β-hydroxydiisophorone in yields of 10% (52 mg) and 20% (103 mg), respectively. The structure was established by IR, specific rotation, mass spectral, 1D and 2D-NMR studies.Revisions requested 2 March 2005 and 21 April 2005; Revisions received 8 April 2005 and 10 May 2005  相似文献   

15.

Background

Bisphenol A (BPA) is a high production volume chemical widely used in food and drinks packaging. Associations have previously been reported between urinary BPA concentrations and heart disease, diabetes and liver enzymes in adult participants of the National Health and Nutrition Examination Survey (NHANES) 2003/04. We aimed to estimate associations between urinary BPA concentrations and health measures in NHANES 2005/06 and in data pooled across collection years.

Methodology and Findings

A cross-sectional analysis of NHANES: subjects were n = 1455 (2003/04) and n = 1493 (2005/06) adults aged 18–74 years, representative of the general adult population of the United States. Regression models were adjusted for age, sex, race/ethnicity, education, income, smoking, BMI, waist circumference, and urinary creatinine concentration. Main outcomes were reported diagnoses of heart attack, coronary heart disease, angina and diabetes and serum liver enzyme levels. Urinary BPA concentrations in 2005/06 (geometric mean 1.79 ng/ml, 95% CI: 1.64 to 1.96) were lower than in 2003/04 (2.49 ng/ml, CI: 2.20 to 2.83, difference p-value = 0.00002). Higher BPA concentrations were associated with coronary heart disease in 2005/06 (OR per z-score increase in BPA = 1.33, 95%CI: 1.01 to 1.75, p = 0.043) and in pooled data (OR = 1.42, CI: 1.17 to 1.72, p = 0.001). Associations with diabetes did not reach significance in 2005/06, but pooled estimates remained significant (OR = 1.24, CI: 1.10 to 1.40, p = 0.001). There was no overall association with gamma glutamyl transferase concentrations, but pooled associations with alkaline phosphatase and lactate dehydrogenase remained significant.

Conclusions

Higher BPA exposure, reflected in higher urinary concentrations of BPA, is consistently associated with reported heart disease in the general adult population of the USA. Studies to clarify the mechanisms of these associations are urgently needed.  相似文献   

16.
Brassica juncea L. eight-day-old seedlings treated with various concentrations (50–200 µM) of copper for 48 h accumulated Cu more in the roots than in leaves. Accumulation of copper resulted in more active lipid peroxidation and depletion of glutathione (GSH) pools in both roots and shoots, which was attributed to copper-induced additional oxidative stress. Activities of ascorbate peroxidase and superoxide dismutase were higher in both roots and shoots while catalase activity increased in leaves but remained unchanged in roots in response to copper accumulation. Changes in lipid peroxidation, GSH content, and antioxidant enzyme activities suggest that oxidative damage may be involved in copper toxicity.From Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 233–237.Original English Text Copyright © 2005 by Devi, Prasad.This article was submitted by the authors in English.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

17.
A database called eukaryotic intron database (EID) was developed based on the data from GenBank. Studies on the statistical characteristics of EID show that there were 103, 848 genes, 478,484 introns, and 582,332 exons, with an average of 4.61 introns and 5.61 exons per gene. Introns of 40–120 nt in length were abundant in the database. Results of the statistical analysis on the data from nine model species showed that in eukaryotes, higher species do not necessarily have more introns or exons in a gene than lower species. Furthermore, characteristics of EID, such as intron phase, distribution of different splice sites, and the relationship between genome size and intron proportion or intron density, have been studied. __________ Translated from Acta Scientiarum Naturalium Universitatis Sunyatseni, 2005, 44(6): 79–82 [译自: 中山大学学报, 2005, 44(6): 79–82]  相似文献   

18.
Harmful algal blooms (HABs) resulting in red discoloration of coastal waters in Sepanggar Bay, off Kota Kinabalu, Sabah, East Malaysia, were first observed in January 2005. The species responsible for the bloom, which was identified as Cochlodinium polykrikoides, coincided with fish mortalities in cage-cultures. Determinations of cell density between January 2005 and June 2006 showed two peaks that occurred in March–June 2005 and June 2006. Cell abundance reached a maximum value of 6 × 106 cells L−1 at the fish cage sampling station where the water quality was characterized by high NO3–N and PO4–P concentrations. These blooms persisted into August 2005, were not detected during the north–east monsoon season and occurred again in May 2006. Favorable temperature, salinity and nutrient concentrations, which were similar to those associated with other C. polykrikoides blooms in the Asia Pacific region, likely promoted the growth of this species. Identification of C. polykrikoides as the causative organism was based on light and scanning microscopy, and confirmed by partial 18S ribosomal DNA sequences of two strains isolated during the bloom event (GenBank accession numbers DQ915169 and DQ915170).  相似文献   

19.
A massive fish kill and water discoloration were reported off the western coast of Puerto Princesa, Palawan, Philippines in March 2005. Phytoplankton analysis revealed a near monospecific bloom of the dinoflagellate, Cochlodinium polykrikoides, with cell concentrations ranging from 2.5 × 105 to 3.2 × 106 cells per liter. Ground truth data were supplemented by processed satellite images from MODIS Aqua Level 2 data (1 km resolution) from January to April 2005, which revealed high surface chlorophyll-a levels (up to 50 mg/m3) offshore of west and southwest Palawan as early as February 2005. The bloom extended 310 km in length and 80 km in width at its peak in March off the central coast (Puerto Princesa). By April, the bloom declined in intensity, but was still apparent along the northern coast (El Nido). Fluctuations in chlorophyll levels off the western coast of Sabah, Malaysia and Brunei during this time period suggested that the bloom was not limited to the coast of Palawan. Satellite imagery from Sabah in late January revealed a plume of chl-a that is believed to be the source of the C. polykrikoides bloom in Palawan. This plume drifted offshore, advected northward via the basin-wide counterclockwise gyre, and reached nutrient-rich, upwelled waters near Palawan (due to a positive wind stress curl) where the dinoflagellate bloomed and persisted for 2 months from March to April 2005.  相似文献   

20.
Two extracellular oxidases (laccases) were isolated from the extracellular fluid of the fungus Panus (Lentinus) tigrinus cultivated in low-nitrogen medium supplemented with birch sawdust. The enzymes were purified by successive chromatography on columns with TEAE-cellulose and DEAE-Toyopearl 650M. Both oxidases catalyze oxidation of pyrocatechol and ABTS. Moreover, oxidase 1 also catalyzes oxidation of guaiacol, o-phenylenediamine, and syringaldazine. The enzymes have identical pH (7.0) and temperature (60–65°C) optimums. Absorption spectra of the oxidases differ from the spectra of typical “blue” laccases and are similar to the spectrum of yellow oxidase.__________Translated from Biokhimiya, Vol. 70, No. 6, 2005, pp. 850–854.Original Russian Text Copyright © 2005 by Cadimaliev, Revin, Atykyan, Samuilov.  相似文献   

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