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941.
I. N. Kurganova A. M. Yermolaev V. O. Lopes de Gerenyu A. A. Larionova Ya. Kuzyakov T. Keller S. Lange 《Eurasian Soil Science》2007,40(1):51-58
A quantitative assessment of the carbon balance was performed in gray forest soils of the former agricultural lands abandoned in different time periods in the southern part of Moscow oblast. It was based on the field measurements of the total and heterotrophic soil respiration and the productivity of biocenoses. Geobotanical investigations demonstrated that the transformation of the species composition of herbs from weeds to predominantly meadow plants occurred in five–ten years after the soil was no more used for farming. The amount of carbon assimilated in the NPP changed from 97 g C/m2 year in the recently abandoned field to 1103 g C/m2 year in the 10-year-old fallow, and the total annual loss of carbon from the soil in the form of CO2 varied from 347 to 845 g C/m2 year. In five years, the former arable lands were transformed into meadow ecosystems that functioned as a stable sink of carbon in the phytomass and the soil organic matter. 相似文献
942.
Sohn EJ Paape MJ Bannerman DD Connor EE Fetterer RH Peters RR 《Veterinary research》2007,38(1):95-108
CD14, the leukocyte co-receptor for lipopolysaccharide (LPS), is important in the response of bovine polymorphonuclear neutrophil leukocytes (PMN) to Gram-negative bacteria. In other species, the expression of CD14 on the surface of PMN was shown to increase after exposure to inflammatory stimuli. These newly expressed molecules may originate from either an intracellular pool or through new gene expression. We sought to characterize bovine PMN cell surface expression and shedding of CD14 molecules, and CD14's effect on secretion of the chemoattractants IL-8 and IL-1beta by PMN. Bovine PMN were incubated in RPMI for 20 h at 37 degrees C with LPS (1, 10, 100 microg/mL). IL-8 release increased with treatment of 1 microg/mL LPS, but decreased 41.5 and 95% at the 10 and 100 microg/mL concentrations of LPS, respectively. In contrast, shedding of CD14 from the surface of PMN only increased at the highest concentration of LPS (100 microg/mL). Secretion of IL-1beta was similar regardless of the LPS concentration used to stimulate PMN. The effect of PMN concentration (1 x 10(7), 2.5 x 10(7), 5 x 10(7), and 10 x 10(7)/mL) on CD14 cell surface expression and shedding of IL-8 and IL-1beta were also determined. Shedding of CD14 by PMN increased with increasing concentration of PMN after exposure to 0.1 and 10 microg/mL of LPS, while secretion of IL-8 decreased. IL-1beta increased at the highest concentration of PMN. The use of real time polymerase chain reaction showed that CD14 mRNA expression was not different between control and LPS-stimulated cells, indicating that the sCD14 came from either membrane bound CD14 or a preformed pool. Our results demonstrate that release of CD14 from PMN suppresses secretion of IL-8, and may be an important regulatory mechanism for controlling excessive migration of PMN into the bovine mammary gland. 相似文献
943.
Yang?Liu Heinrich?BuchenauerEmail author 《European journal of plant pathology / European Foundation for Plant Pathology》2005,113(3):283-295
Interactions between Barley yellow dwarf virus (BYDV) and Fusarium species causing Fusarium head blight (FHB) in winter wheat cvs Agent (susceptible to FHB) and Petrus (moderately resistant
to FHB) were studied over three years (2001–2003) in outdoor pot experiments. FHB developed more rapidly in cv. Agent than
in cv. Petrus. The spread of FHB was greater in BYDV-infected plants than in BYDV-free plants. Thousand grain weight (TGW)
was reduced more in Fusarium-infected heads of cv. Agent than in cv. Petrus. A highly significant negative correlation was found between disease index
and TGW in cv. Agent (r = −0.916), while in cv. Petrus the correlation was less significant (r = −0.765). Virus infection reduced TGW in cv. Petrus more than in cv. Agent. In plants with both infections, TGW reductions
in cv. Petrus corresponded to those of BYDV infection, and in cv. Agent TGW was more diminished than in BYDV infection. Effects
of different treatments determined over three years on ergosterol contents in grain were generally similar to effects on disease
indices. Grain weight per ear and ear weight of the different treatments of both cultivars largely corresponded with the TGW
results. Deoxynivalenol (DON) content in grain of cv. Agent infected with Fusarium spp. was 11–25 times higher compared to the corresponding treatments in cv. Petrus. The DON content in grain of plants of
the two cultivars infected with both pathogens was higher than that of plants infected only with Fusarium over the three years. 相似文献
944.
G. Wess A. Schulze V. Butz J. Simak M. Killich L.J.M. Keller J. Maeurer K. Hartmann 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(3):533-538
Background: Dilated cardiomyopathy (DCM) in Doberman Pinschers is an autosomal dominant inherited disease. The prevalence of DCM in Doberman Pinschers of various age groups in Europe is currently unknown, but this information would be important to develop recommendations for screening programs. Objectives: To evaluate the prevalence of cardiomyopathy in various age groups of Dobermans. Animals: Seven hundred and seventy‐five examinations in 412 Doberman Pinschers. Methods: Dogs were included in a prospective longitudinal cohort study. Each examination included echocardiography and 24‐hour ECG (Holter) examination. A cut‐off value of >100 ventricular premature contractions (VPCs) per 24 hours on Holter examination or abnormal echocardiography was considered diagnostic for cardiomyopathy. The cumulative prevalence included all dogs with DCM and healthy dogs >7 years of age. Results: DCM prevalence in various age groups was as follows: age group 1 (1 to <2 years) 3.3%, age group 2 (2 to <4 years) 9.9%, age group 3 (4 to <6 years) 12.5%, age group 4 (6 to <8 years) 43.6%, and age group 5 (>8 years) 44.1%. The cumulative prevalence of Doberman Pinscher cardiomyopathy was 58.2%. There was an equal sex distribution, but male dogs showed earlier echocardiographic changes than did female dogs, which had significantly more VPCs. Conclusions and Clinical Importance: The prevalence of Doberman cardiomyopathy is very high in Europe. Disease manifestation and progression are different between male and female dogs. Yearly screening for DCM by Holter examination and echocardiography is recommended, starting at 2 years of age. 相似文献
945.
Webb JA Keller SL Southorn EP Armstrong J Allen DG Peregrine AS Dubey JP 《Journal of the American Animal Hospital Association》2005,41(3):198-202
A 3.5-year-old, castrated male, giant schnauzer was presented with alopecic pustular dermatitis. Immune-mediated hemolytic anemia had been diagnosed 45 days previously. At the time of presentation, the dog was receiving prednisone, azathioprine, and cyclosporine. Cutaneous protozoosis was diagnosed, and postmortem examination revealed protozoa within cutaneous, cardiac, pancreatic, and pulmonary tissues. The protozoa divided by endodyogeny, had the morphology of Toxoplasma gondii (T. gondii) tachyzoites, and stained positively with T. gondii polyclonal antibodies but not with antibodies to Neospora caninum or Sarcocystis neurona. Immunosuppression may have predisposed this dog to disseminated toxoplasmosis. 相似文献
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