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Air pollution induced changes in pine needle chemistry were observed at sample sites in the surroundings of the Pechenganikel smelter. Close to the smelter, elevated concentrations of Ni, Cu and S were found (Ni: 0.7–1 mmol/kg, Cu: 0.4–0.5, and S 40–60 mmol/kg). Close to the pollution source, needles were enriched in Ni and Cu by needle age. Correlation and principal component analyses show that changes in the element composition of pine needles depended on air pollution and on natural factors as well. The contribution from air pollution increased with needle age. Besides direct input of pollutants from atmosphere, soil contamination and nutritional disturbance contributed significantly to the observed changes.  相似文献   
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Upper limits for soil nitrate in late fall as function of soil properties, climate and soil use: Model considerations Strategies and measures to reduce the leaching of nitrate from agricultural soils can only be successful if possibilities of control are available. In temperate regions measurement of soil mineral nitrogen (predominantly nitrate) in late fall, together with appropriate upper limits for tolerable soil nitrate, can be considered as an efficient control instrument. With assumptions about the mineralization of crop residues and the input of nitrate from the atmosphere, a procedure is developed with which the nitrate leaching in winter can be estimated if the amount of soil nitrate in late fall is known. With the procedure sample calculations for the crop rotation sugarbeets-summer wheat-winter barley are carried out for a variety of site conditions. The calculations show, that when no residual nitrate is left in the soil at the time of harvest, the cumulative amount of leached nitrate for the crop rotation (due to mineralization of residues) is 63.7 kg/ha NO3? N. However, when each year an amount of soil mineral nitrogen of 45 kg/ha in late fall is allowed for, the leached amount of soil nitrate can, for average site conditions, be as high as 133.6 kg/ha. It is shown how with the model in a rational way late fall site- and crop-specific upper limits for soil nitrate can be derived. However, the stipulation of such upper limits is not a matter of soil science only.  相似文献   
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This article describes the reproductive physiology of Zebu cattle and specific strategies that, when used in concert with an understanding of the physiologic differences between Zebu and other cattle, can improve reproductive performance.  相似文献   
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Transient receptor potential vanilloid 1 receptors (TRPV1) play a significant physiological role. The study of novel TRPV1 agonists and antagonists is essential. Here, we report on the characterization of polypeptide antagonists of TRPV1 based on in vitro and in vivo experiments. We evaluated the ability of APHC1 and APHC3 to inhibit TRPV1 using the whole-cell patch clamp approach and single cell Ca2+ imaging. In vivo tests were performed to assess the biological effects of APHC1 and APHC3 on temperature sensation, inflammation and core body temperature. In the electrophysiological study, both polypeptides partially blocked the capsaicin-induced response of TRPV1, but only APHC3 inhibited acid-induced (pH 5.5) activation of the receptor. APHC1 and APHC3 showed significant antinociceptive and analgesic activity in vivo at reasonable doses (0.01–0.1 mg/kg) and did not cause hyperthermia. Intravenous administration of these polypeptides prolonged hot-plate latency, blocked capsaicin- and formalin-induced behavior, reversed CFA-induced hyperalgesia and produced hypothermia. Notably, APHC3’s ability to inhibit the low pH-induced activation of TRPV1 resulted in a reduced behavioural response in the acetic acid-induced writhing test, whereas APHC1 was much less effective. The polypeptides APHC1 and APHC3 could be referred to as a new class of TRPV1 modulators that produce a significant analgesic effect without hyperthermia.  相似文献   
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Background

Anaplasmosis is a vectorborne disease caused by the gram-negative bacterium Anaplasma phagocytophilum. This species displays positive tropism to granulocytes and can cause illness in several mammalian species, including cats, dogs, and humans. It is considered as an emerging disease in Europe. The clinical signs are nonspecific and include fever, lethargy, and inappetence. The most typical hematologic abnormality is thrombocytopenia. A tentative diagnosis can be made by detecting intracytoplasmic morulae inside neutrophils. The diagnosis is confirmed by PCR and serology in paired serum samples. A sample for PCR analysis should be taken before treatment. Anaplasmosis is treated with doxycycline.

Case presentation

A feline case of anaplasmosis is presented. The history, clinical presentation, diagnostics, treatment, and follow-up are discussed.

Conclusions

This case indicates that Anaplasma phagocytophilum infects cats in Finland. To provide accurate treatment, anaplasmosis should be listed as a differential diagnosis in cats suffering from acute febrile illness with previous tick exposure.  相似文献   
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