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901.
In summer 2007, leaf and stem rot of ice plants was found in a hydroponic greenhouse in Japan. The causal agent was a fungus identified as Choanephora cucurbitarum (Berkeley & Ravenel) Thaxter, based on pathogenicity, morphology, mating tests, and sequence analysis of the ribosomal DNA ITS region.  相似文献   
902.
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905.
The present study examined the effect of excessive application of farmyard manure (FM) on rice production and environmental pollution in paddy fields of Japan. A long-term field experiment was conducted during the period 1976–2006 to examine the trends of rice yield and yield components as affected by the excessive FM application (20 Mg ha?1 year?1 containing 110 kg N, 180 kg P2O5, and 320 kg K2O). Rice growth, soil fertility, and surface water quality were also assessed in the final year (2006). The results obtained were compared with those of a conventional practice with recommended doses of inorganic fertilizer (IF), i.e. 85 kg N, 68 kg P2O5, and 53 kg K2O ha?1 year?1, and an unfertilized control (CR). The excessive FM application resulted in a gradual decrease in grain yield, which was mostly explained by the reduction of grain fertility under the luxuriant rice growth. This reduction may have been due to the higher accumulation of soil nutrients such as N, P, and K. Moreover, the excessive FM application increased chemical oxygen demand, total P, and soluble K concentrations in the paddy surface water and their effluent loads compared to the conventional practice with the recommended IF application.  相似文献   
906.
Cyazofamid (ISO proposed common name), 4-chloro-2-cyano-N,N-dimethyl-5-p-tolylimidazole-1-sulfonamide is a novel fungicide exhibiting specific activity against diseases caused by Oomycetes. In tests, cyazofamid at 0.4-1.6 mg litre-1 exhibited excellent preventative activity against Phytophthora infestans on tomato and Pseudoperonospora cubensis on cucumber. Minimum inhibitory concentrations of cyazofamid against both diseases were over 63 times lower than those of mancozeb and at least 16 times lower than those of metalaxyl. Cyazofamid at 1.6-25 mg litre-1 exhibited not only preventative activity, but also stable residual activity and rainfastness. Cyazofamid at 6.3 mg litre-1 reduced zoosporangia formation of P infestans and P cubensis on host plants by 100 and 94% respectively. Cyazofamid also exhibited translaminar and curative activity. Cyazofamid has a new mode of action for fungicides and exhibits no cross-resistance with other currently registered and commonly used fungicides. These properties lead to a high level control by cyazofamid in field.  相似文献   
907.
To elucidate the physiological role of insulin-like growth factor-I (IGF-I) during early pregnancy in mares, number of ovarian follicles was monitored ultrasonically during different stages of the first trimester of pregnancy in 36 thoroughbred mares. From 9 of 36 mares, blood samples were collected weekly from the mating day till the end of the first trimester of pregnancy and plasma IGF-I profiles were examined with other hormones, like follicle stimulating hormone (FSH), luteinizing hormone (LH), ir-inhibin, progesterone and estradiol-17beta. Plasma IGF-I level fluctuated throughout the studied period with four peaks on the 7th, 28th, 49th and 84th days of pregnancy. Plasma IGF-I showed a positive correlation with plasma FSH (P<0.05), whereas no correlation was found with other hormones during the studied period. Plasma IGF-I had no correlation with the foetal size, but positive correlation with the number of large (> 30 mm) and medium (10-30 mm) follicles. These results suggested that IGF-I might produce from the medium and large follicles during early pregnancy and promote to develop their growth via pituitary FSH mediated effects in the mares.  相似文献   
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909.
Massive lobar emphysema in the middle lobe of the right lung was observed in a dog brought to our clinic with sudden onset of tension pneumothorax, and lobectomy was performed to excise it. Pathological examination resulted in a diagnosis of congenital bronchiectasis associated with bronchial cartilage hypoplasia. Two cases of diagnosis and successful treatment of congenital lobar emphysema have been reported in dogs.  相似文献   
910.
The genome of porcine circovirus type 2 (PCV2) contains two major open reading frames, which have been shown to encode the virus capsid and replication-associated proteins. The capsid protein is a major structural protein of the virus; it can be a suitable target antigen for detecting PCV2-specific antibodies to monitor PCV2 infection. To produce the antigen, the capsid protein coding sequence was cloned into a baculovirus transfer vector, and a recombinant capsid (rC) protein of PCV2 was expressed as a combined fusion protein in frame with a C-terminal peptide of six histidines. The affinity-purified rC protein was used as coating antigen to develop an ELISA for detecting the virus-specific antibodies in swine sera. The rC protein-based ELISA (rcELISA) was evaluated by examining a panel of 49 PCV2-positive and 49 PCV2-negative swine sera. In comparative experiments of immunoperoxidase monolayer assay (IPMA) using 102 field sera, there was 89.2% coincidence between data obtained by the rcELISA and IPMA. The rcELISA achieved 88.5% specificity and 89.4% sensitivity for detection of PCV2 antibody in the field sera. The assay showed no cross-reactivity with antibodies to PCV type 1, porcine reproductive and respiratory syndrome virus and porcine parvovirus. The results suggest that the rcELISA is suitable for routine serodiagnosis and epidemiological surveys of PCV2-associated diseases.  相似文献   
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