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101.
An enzyme-linked immunosorbent assay (ELISA) was developed to measure total antibody to Toxoplasma gondii in serum samples from macropods. The validity of the assay was established by comparing parasite isolation in mice for 17 Tasmanian pademelons (Thylogale billardierii) and 17 Bennett's wallabies (Macropus rufogriseus rufogriseus). The ELISA was then used to detect antibody against T. gondii in serum from 236 macropods, collected from 21 locations in Tasmania, including Flinders Island. Antibody against T. gondii was detected in 20 animals (15 T. billardierii and 5 M. rufogriseus). There was a significant (p less than 0.01) difference in possession of T. gondii antibodies between adult (greater than or equal to 1 year of age) Tasmanian pademelons and Bennett's wallabies. 相似文献
102.
A comparison was made of the fungistatic effects of the root microflora of grey alder and Norway spruce with Fomes annosus as test fungus. The significantly higher frequency of actinomycetes in the alder rhizosphere probably constituted the main difference in this respect. The importance of fungi seemed to be about equal in the rhizosphere of the two tree species. Methods for studies of antagonism are tested and discussed. 相似文献
103.
The objective was to determine stem volume models for grey andcommon alders and, based on the models, stand volume for naturallyregenerated grey and common alder stands was summarized. Basicdensity for grey and common alders and mean annual growth forstands was estimated. Net volume accretion data were collectedfrom 24 stands of grey alder (Alnus incana (L.) Moench) and31 stands of common alder (Alnus glutinosa (L.) Gaertner) inSweden. The stands ranged in latitude from 58 to 64° N andfrom 56 to 62° N for grey and common alder, respectively.The mean age of grey and common alder stands was 41 years and48 years, respectively, the mean stand density 1726 stems ha1and 1078 stems ha1, and the mean diameter at breast height(over bark) was 20 cm and 21 cm. Stem volume equations weredeveloped for grey and common alders. The adopted model forgrey alder was based on diameter at breast height and height.For common alder, crown height was added to diameter and height.Mean standing volume (over bark) for grey and common alder standswas 428 and 374 m3 ha1. Mean annual growth for grey andcommon alder stands was 12.0 m3 and 8.4 m3 a1 ha1,respectively. Basic density (under bark), for grey and commonalder stems was 359 and 427 kg m3, respectively. Thebasic density (under bark) for the lowest twigs in the crownand in the lateral part of the crown was 415 and 421 kg m3for grey alder and 423 and 423 kg m3 for common alder. 相似文献
104.
Orfanos P Naska A Trichopoulos D Slimani N Ferrari P van Bakel M Deharveng G Overvad K Tjønneland A Halkjaer J Santucci de Magistris M Tumino R Pala V Sacerdote C Masala G Skeie G Engeset D Lund E Jakszyn P Barricarte A Chirlaque MD Martinez-Garcia C Amiano P Quirós JR Bingham S Welch A Spencer EA Key TJ Rohrmann S Linseisen J Ray J Boeing H Peeters PH Bueno-de-Mesquita HB Ocke M Johansson I Johansson G Berglund G Manjer J Boutron-Ruault MC Touvier M Clavel-Chapelon F Trichopoulou A 《Public health nutrition》2007,10(12):1515-1525
105.
Boutet S Lomb L Williams GJ Barends TR Aquila A Doak RB Weierstall U DePonte DP Steinbrener J Shoeman RL Messerschmidt M Barty A White TA Kassemeyer S Kirian RA Seibert MM Montanez PA Kenney C Herbst R Hart P Pines J Haller G Gruner SM Philipp HT Tate MW Hromalik M Koerner LJ van Bakel N Morse J Ghonsalves W Arnlund D Bogan MJ Caleman C Fromme R Hampton CY Hunter MS Johansson LC Katona G Kupitz C Liang M Martin AV Nass K Redecke L Stellato F Timneanu N Wang D Zatsepin NA Schafer D Defever J 《Science (New York, N.Y.)》2012,337(6092):362-364
Structure determination of proteins and other macromolecules has historically required the growth of high-quality crystals sufficiently large to diffract x-rays efficiently while withstanding radiation damage. We applied serial femtosecond crystallography (SFX) using an x-ray free-electron laser (XFEL) to obtain high-resolution structural information from microcrystals (less than 1 micrometer by 1 micrometer by 3 micrometers) of the well-characterized model protein lysozyme. The agreement with synchrotron data demonstrates the immediate relevance of SFX for analyzing the structure of the large group of difficult-to-crystallize molecules. 相似文献
106.
Chemical fixation of NH3 to soil organic matter was studied in two Swedish soils with different contents of organic matter: a clay soil with 2.3% C and an organic soil with 36.6% C. 15N‐labelled urea was applied at different rates to both sterilized and non‐sterilized soils. After 10 days, the soils were extracted and washed with K2SO4 and determined for total N and atom% 15N excess. Urea N was recovered as non‐extractable N in sterilized soil corresponding to 9.7% of supplied l5N‐labelled urea in the organic soil and 2.2% in the clay soil. Since no biological immobilization is thought to occur in the sterile soil, this non‐extractable N is suggested to be chemically fixed to soil organic matter. Owing to urea hydrolysis in the clay soil, pH increased from 6.3 to 9.3 and in the organic soil from 5.7 to 6.9 and 8.8, respectively, at the low and high urea supply. 相似文献
107.
Robert S. Fritz Leif Johansson Boel åstrom Mauritz Ramstedt Håkan HÄggström 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(9):875-881
Pure species and F1 hybrid families ofSalix viminalis andS. dasyclados were tested for resistance to four single uredinium isolates ofMelampsora rust in laboratory experiments using excised leaves. Rust isolates were derived from:S. viminalis, S. dasyclados, aS. viminalis x triandra hybrid, andS. daphnoides. Incidence of infection, number of uredinia per leaf, and numbers of spores per uredinium were measured. As expected, the isolate fromS. daphnoides did not infect any of the willow species or hybrids tested. For the other three rust isolates that were tested, the parent from which the isolate was derived was susceptible, the other parent was resistant, and hybrids were intermediate in resistance for incidence and uredinia per leaf. These patterns indicate additive inheritance of these resistance traits in hybrids. Numbers of spores per uredinium were similar on the hybrids and the susceptible parent for one rust isolate, suggesting dominant inheritance of this trait in the hybrids. 相似文献
108.
Validation of human recombinant tissue factor-activated thromboelastography on citrated whole blood from clinically healthy dogs 总被引:1,自引:0,他引:1
Wiinberg B Jensen AL Rojkjaer R Johansson P Kjelgaard-Hansen M Kristensen AT 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):389-393
BACKGROUND: Thromboelastography (TEG) is an analytical method that enables global assessment of hemostatic function in whole blood (WB) with evaluation of both plasma and cellular components of hemostasis. TEG has a largely unused potential in the diagnostic workup and monitoring of dogs with hemostatic disorders and it may be a valuable supplement to traditional coagulation parameters. OBJECTIVES: The objective of this study was to establish a clinically applicable reference interval for a TEG assay using recombinant human tissue factor (TF) as the activator on citrated WB from clinically healthy dogs and to evaluate the stability of citrated WB stored for 30 minutes (T30) and 120 minutes (T120) at room temperature (RT). Additionally, we evaluated the analytical variation in reaction time (R), clotting time (K), angle (alpha), and maximum amplitude (MA). METHODS: Blood was collected from 18 clinically healthy dogs. Duplicate TEG analyses with TF as the activator at a concentration of 1:50,000 were performed on canine citrated WB at T30 and T120. R, K, a, and MAwere analyzed. RESULTS: Mean TEG values at T30/T120 were R = 5.61/4.91 minutes, K = 4.20/3.34 minutes, alpha = 45.33/50.90 degrees , and MA = 47.96/50.19 mm. Significant differences in these values were observed after storage for T30 and T120 at RT, with a tendency towards hypercoagulability at T120. The mean coefficients of variation were low. CONCLUSIONS: Canine citrated WB can be used for TEG analysis with human recombinant TF as the activator when stored at RT for T30 or T120. At both time points, the analytical variation was low, suggesting that TEG analysis may be of value in evaluating dogs with hemostatic disorders. A fixed time point should be chosen for serial measurements. 相似文献
109.
The 16S rRNA genes from eight isolates of Renibacterium salmoninarum with different origins and dates of isolation were sequenced to evaluate the possibility to construct a diagnostic PCR system with target sites within this gene. The sequences were found to be identical but for one single position in one of the isolates, and two regions with an adequate number of nucleotide differences as compared to closely related species were identified. Species-specific fluorescent PCR primers complementary to these regions were constructed as well as oligonucleotides for DNA preparation by sequence capture. A mimic molecule was constructed to be used as an internal control. The PCR was specific and allowed the detection of DNA equivalent to 1-10 R. salmoninarum genomes per reaction. The DNA preparation with sequence capture and analysis by PCR with a mimic was found to be a reliable method for analysis of kidneys from fish with BKD. The amount of PCR inhibiting substances present in the tissue was reduced, and the relevant DNA was concentrated in the capture step. Furthermore, the use of the mimic molecule in the system assured that false negative results could be identified. 相似文献
110.
The possibility to use acute phase proteins to monitor the elimination of a bacterial infection in pigs would facilitate an objective assessment of treatment with various antimicrobial substances. To examine this possibility, the acute phase response (IL-6, serum amyloid A (SAA), and haptoglobin) elicited by Actinobacillus pleuropneumoniae and its reduction on treatment with various antibiotics was studied in serum from specific pathogen free (SPF) pigs. Pigs were infected intranasally with A. pleuropneumoniae serotype 2, and either left as non-treated control pigs or treated with different antibiotics intramuscularly at onset of respiratory disease (20h post-infection). Pigs responded to the infection with prominent increases in activity and concentrations of IL-6, SAA, and haptoglobin. These responses were to a certain extent overlapping and covered the time span from a few hours after infection until development of detectable levels of specific antibodies (7-10 days post-infection in untreated pigs). The haptoglobin response lasted until the end of the study on day 17 and thereby partly coincided with the antibody response. Treatment with antimicrobials that effectively reduced establishment of the infection with A. pleuropneumoniae also reduced the duration of all three acute phase responses, and reduced the concentration of serum haptoglobin. In contrast, less efficacious treatments did not reduce these acute phase responses. Thus, acute phase reactants can be applied to monitor therapeutic effects of antimicrobial drugs in the pig and measurements of IL-6, SAA and haptoglobin could add valuable information about the stage of infection during a disease outbreak. 相似文献