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1.
Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types.  相似文献   
2.
Use of carefully lifted, decapitated cauliflower plants with 6 to 7 leaves per se, eliminated the need of the rooting of shoots and provided seeds in reduced time. Previously, shoots obtained from decapitated and de-leafed plants were rooted and allowed to produce seeds. This latter method did not assure that seed would be available in time for the following season's planting.  相似文献   
3.
For better understanding wood hardness, we developed a new hand-operated hardness tester that works with Brinell's method. With this tester we investigated the hardness distribution of wood minutely using a 2mm diameter ball tip. The following results were obtained: (1) On preliminary examination with medium-density fiberboard, we found that the value of Brinell's hardness decreased with the increase in the tip ball's diameter but that it was almost constant with the indenting velocity. (2) By using a small diameter tip, the difference of the hardness became clearer between earlywood and latewood. (3) With radial and tangential sections, we obtained hardness distribution patterns similar to those of wood grain. It seems that the hardness distribution reflects the distribution of density on wood surfaces.  相似文献   
4.
W. L. Summers  S. Honma 《Euphytica》1975,24(3):771-773
Summary Propagating summer cauliflower selections for seed production has been difficult due to soft rot and other diseases. A portable compressed air powder blower and evaporative cooling in the greenhouse has increased the percent surival of selected plants for seed production.Michigan Agricultural Experiment Station Journal Articule No. 7105.  相似文献   
5.
Summary We obtained success in seed production by transplanting matured head lettuce plants into clay pots after (1) removing the head with a knife, leaving a few leaves on the stalk to allow for the development of the shoots, and (2) after removing all leaves covering the seedstalk so that it was free to bolt. The use of gibberellin A3 (GA3) to promote early seed production proved detrimental on poorly established transplants.  相似文献   
6.
Summary The action of the X locus in the tomato was explored by studying meiotic behavior, pollen germination, pollen tube growth, and fertilization capability. Normal meiosis was observed suggesting no x meiotic lethality. Percent germination showed much variation from test to test depending on size of population. X and x pollen from homozygous sources showed no differences in pollen tube growth capability or fertilization capability. Pollen from the F1 plant had a lower mean pollen tube length than either X and x pollen. Using F1 pollen in backcrosses to the recessive parent resulted in deviations from expected segregation ratios for characters linked to x.Michigan Agricultural Experiment Station Article No. 5374.  相似文献   
7.
Summary Hybridization between tomato with xx and XX gametophytic genotypes exhibited in segregating generations, deviations from the expected monogenic inheritance of Fusarium wilt resistance conditioned by gene I. These deviations resul ted from gametophytic preference, linkage and the presence of modifying loci associated with the gene I. Although information on the inheritance of Fusarium wilt resistance is based on backcross data, information obtained from the pedigree procedure and testcrosses made with BC1S2 plants all supports the presence of modifiers.Michigan Agricultural Experiment Station Journal Number 5457.  相似文献   
8.
A latex agglutination test was evaluated as a method for the detection and titration of antibodies against swine Haemophilus infection and it was found that the test is applicable to the etiologic diagnosis of Haemophilus infection in swine. In swine infected experimentally with H. pleuropneumoniae (H. parahaemolyticus), the micromethod of agglutination using latex particles coated with antigens of H. pleuropneumoniae was found to be comparable agar-gel immunodiffusion and complement-fixation tests, which have previously been used for the etiologic diagnosis of the disease. Antibody titers determined by the latex agglutination test corrlated well with those determined by the other serological tests. The latex agglutination test tended to detect antibodies earlier than any of the other tests. By the latex agglutination test, weak cross-reactions were observed among different serotypes of H. pleuropneumoniae, whereas no cross-reaction was demonstrated between H, pleurophneumoniae and H. parasuis. The latex agglutination test was found to be simple and useful for the serological survey of swine Haemophilus infection, especially when dealing with a large number of samples.  相似文献   
9.
Agar blocks colonized by Sclerotinia sclerotiorum, causal agent of lettuce drop, were used as inoculum in screening for resistance to this pathogen in the greenhouse.Since the degree of resistance to the pathogen among cultivars varied with the time observed after inoculation, resistance was assessed by the number of days for 50% of the plants of each cultivar to die, as well as the number of plants that died. The cultivars ‘PI (Plant Introduction) 250427’, ‘Taiwan’, ‘PI 251790’, ‘PI 255568’, ‘MSU 73-44’ and ‘Bibb’ were found to have a higher level of resistance to S. sclerotiorum than the cultivar ‘Grand Rapids’ at 12 or 15 days following inoculation.  相似文献   
10.
Three hyperimmune dogs were injected intramuscularly with canine wild rabies virus. The dogs showed no clinical evidence of rabies. Intramuscular injection of the wild rabies virus in susceptible puppies induced fulminating disease and mortality in 14 to 16 days. Investigation of the serum proteins of the hyperimmune dogs by a paper electrophoresis technique revealed conspicuous changes in the beta and gamma protein bands.  相似文献   
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