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31.
Most of the fruits formed on muskmelon go to waste due to premature shedding, insect punctures and rotting. An experiment was conducted to test the value of controlling insect damage, eliminating contact of fruits with the soil, avoiding continuous contact of the same part of fruits with the soil, and prophylactic application of fungicides on and around fruits, in saving the fruits from rotting. Placing of fruits on polyethylene sheets was best in reducing the incidence of fruit rot, increasing the yield, and providing high net income. Spraying Bordeaux mixture (6:3:100) on and around the fruits was next best.  相似文献   
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Intestinal tissues obtained from coronavirus-infected embryos and turkeys were examined by fluorescent antibody tissue section technique (FAT). Evidence of viral antigen was demonstrated in the cytoplasm of the intestinal epithelial cells covering the villi. Embryo intestines that were examined from 24 to 96 hours after inoculation were positive for immunofluorescence (IF), whereas bursa of Fabricius was negative. Poults hatched from infected embryos were examined at 2 days of age and were positive for IF. Coronaviral antigen was detected by FAT in the cytoplasm of intestinal epithelial cells of the jejunum, ileum, duodenum, and cecum in all turkeys that were examined from 24 hours to 28 days.  相似文献   
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In our experience, altrenogest has not always been able to exert predictable control over the estrous cycle of the mare. Therefore, we examined 12 mares that were treated with altrenogest to identify reasons for its failure to control the estrous cycle. The mares were fed altrenogest for 15 to 20 days and were examined for follicle development, ovulation, and corpus luteum formation during treatment. Through the use of real-time ultrasonography and radioimmunoassay for progesterone, we concluded that altrenogest was unable to suppress the growth of follicles to preovulatory size in some mares, leading to ovulation during treatment or earlier than expected after the end of treatment. In addition, altrenogest did not appear to shorten the life-spans of the corpora lutea that were formed during treatment; in 4 mares, this resulted in the persistence of corpora lutea after the end of the suggested 15-day periods of treatment. The latter findings led us to suggest that if a luteolytic dose of prostaglandin had been given at the end of altrenogest treatment, there would have been improved control over the estrous cycle. The results of our study confirmed our clinical impressions that altrenogest may be satisfactory to control the equine estrous cycle under some circumstances, but it should not be used when precise control over ovulation is required.  相似文献   
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Equine adenovirus 1 isolated from cauda equina neuritis   总被引:1,自引:0,他引:1  
Equine adenovirus 1 was recovered after four to six passages from two out of three cases of cauda equina neuritis (CEN) using kidney monolayers. Similar treatment of lumbo-sacral spinal cord from six normal horses did not yield adenovirus. All three cases of CEN had antibodies to the neuritogenic myelin protein P2 while immunofluorescence demonstrated that autologous IgG bound to the myelin of affected nerves. Adenovirus was not detected in neural tissue by immunofluorescence.  相似文献   
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Bovine pregnancy-associated glycoprotein-1 (bPAG-1) is predicted to play an essential role during pregnancy and is labelled as a potential biochemical marker of pregnancy in ungulates. We have compared the generation of the glycosylated form of recombinant bPAG-1 (rbPAG-1) by human embryonic kidney 293 (HEK 293) and Chinese hamster ovary (CHO) cells in attached cultures and evaluated the adaptation of the rbPAG-1 transfected cell line to suspension culture. The PAG cDNA was cloned from placental RNA obtained from a slaughtered cow on day 55 of pregnancy. The PAG-pRcRSV expression vector was transfected into HEK 293 and CHO cells. Western blot analysis showed that clonal HEK 293 cells expressed rbPAG-1 better than CHO cells in attached cultures. Transfected HEK 293 cells were adapted to suspension culture in spinner flasks and the rbPAG-1 purified to homogeneity using ion-exchange, pepstatin-sepharose affinity chromatographies and preparative SDS-PAGE. The expression of rbPAG-1 was immunocharacterised using a polyclonal antibody. Our findings indicated that 293 cells are suitable for production of glycosylated form of rbPAG-1 and that the availability of the recombinant glycoprotein will aid in further studies to elucidate the function and structure of the protein.  相似文献   
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