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91.
From the chemical composition of leakage substances, it was concluded that there was greater leakage of micro-molecule components in cucumber fruits which had been chilled to 0°C than in fruit chilled to 5°C. However, leakage of macro-molecule components was greater in the 5°C fruit than in the 0°C fruit with longer periods of storage. These results suggest that the plasmalemma develops leakage in the 0°C fruit, whereas there is membrane breakage in the 5°C fruit.Microscopic observations support this assumption. 相似文献
92.
T. Fukushima 《Scientia Horticulturae》1978,9(3):215-226
By incubating the homogenate of cucumber fruits in vitro, pectin de-methylation was considerably accelerated especially at near neutral pH. Histo-chemical observations based on detection of SH-protein present in sieve tubes, revealed that the cell walls of the fruits chilled at 0°C for 3 days contained the tube constituents, in which pectinmethylesterase was also found. The esterase of the tubes was cold-labile. All the esterases present in a fruit were activated by an addition of ascorbic acid, a reducing agent.The set of these results, together with our previous papers, suggests that in cucumber fruits chilling may at first break the plasmalemma of sieve tubes, whose exudate outflows into the cell walls of tissue cells. The subsequent contact between the tube esterase and wall pectin results in the pectin de-methylation, which makes elastic cell walls rigid and fragile. This ultimately leads to occurrence of water-stress injury. A decrease of redox potential in the chilled fruits may serve for raising the activity of the cold-labile tube esterase. 相似文献
93.
Akira Kobayashi Shigeo Naito Yuki O. Kobayashi Shogo Tsuda Akiko Ohara-Takada Motoyuki Mori 《Journal of General Plant Pathology》2005,71(2):139-143
Resistance to common scab pathogen Streptomyces turgidiscabies of seven potato varieties was compared in the field with a newly developed paper pot method. Seedlings raised in soil in paper pots containing inocula at 1 × 103 to 107cfu/g soil were transplanted into a scab-free field and grown for 3 months. The disease severity of the seven varieties in the field trials differed in iteration and from year to year, even though their resistance levels were approximately similar at the expected levels. With the paper pot method, the seven varieties had different resistance levels, which were almost completely consistent with the results of the field trials, at more than 1 × 105cfu/g soil. Significant differences in disease severity between resistant and susceptible varieties were observed (P = 0.05) for 2 years, and the resistance level of the varieties was elucidated. 相似文献
94.
Yamashita K Shimizu A Kawano J Uchida E Haruna A Igimi S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(3):263-268
Staphylococci were isolated from the external auditory meatus in 14 (48.3%) of 29 dogs affected with otitis externa (OE dogs) and 28 (68.3%) of 41 dogs without OE (non-OE dogs). Twenty-two OE isolates were identified as belonging to 12 species, and 42 non-OE isolates were identified as belonging to 13 species. The predominant species found in both OE and non-OE isolates were S. intermedius, and S. epidermidis. Thirty-eight (59.4%) of 64 isolates were resistant to one or more of the 17 antimicrobial agents tested. Resistance to PCG and ABPC was most frequent. S. schleiferi subsp. coagulans, a recent etiologic agent of canine OE, was isolated from OE and non-OE dogs. All of the 5 S. schleiferi subsp. coagulans isolates showed typical characteristics. No clear difference in the extracellular enzyme or toxin profiles, nor in the PFGE patterns, was demonstrated between the OE and non-OE isolates of S. schleiferi subsp. coagulans. A new PCR primer set specific for 16S rDNA was designed to identify strains of S. schleiferi subsp. coagulans. The amplified fragment was detected in all of the 5 isolates as well as the type strain GA 211 (=JCM 7470) and a reference strain GA 11, but was not detected in any strains of the related species, S. aureus, S. intermedius and S. hyicus. The PCR may allow a simple, rapid and precise identification of S. schleiferi subsp. coagulans, in addition to the standard tube test for free coagulase. 相似文献
95.
Saeki K Sumitomo N Nagata Y Kato N Hosoi Y Matsumoto K Iritani A 《The Journal of reproduction and development》2005,51(2):293-298
The atomic force microscope (AFM) provides nanometer resolution, topographic data of the natural surface structure of materials. We studied the topology of the surface structure of bovine sperm heads during the acrosome reaction by AFM. In addition, we numerically analyzed the areas of the median sagittal plane of the sperm heads. Bovine frozen-thawed spermatozoa were washed, capacitated by heparin, and incubated with lysophosphatidylcholine (LPC) to induce the acrosome reaction, smeared on a cover glass, air-dried, and observed with AFM using the dynamic force (tapping) mode. AFM analysis of spermatozoa showed the clear surface structure of acrosomes, equatorial segments, postacrosomal regions and necks. Although AFM images of spermatozoa capacitated by heparin had complete acrosomes, most spermatozoa treated with LPC had no acrosomal caps as shown by AFM. These observations coincided with those obtained by light microscopy after staining with naphthol yellow S and erythrosin B. Furthermore, numerical analysis of AFM images indicated that areas of the median sagittal plane of the anterior portions of acrosome-reacted sperm heads (2679 +/- 616 pixels) were approximately 40% less than those of intact heads (4535 +/- 174 pixels, P<0.05). These results indicate that AFM can usefully observe and numerically analyze the fine surface structures of bovine spermatozoa. 相似文献
96.
97.
Akira?KawakamiEmail author Naoyuki?Matsumoto Shigeo?Naito 《Journal of General Plant Pathology》2004,70(1):1-6
Environmental factors influencing sporocarp formation in Typhula ishikariensis were studied under controlled conditions. Sporocarp formation in T. ishikariensis was divided into two stages: stipe elongation from the sclerotium and fertile head development at the tip of the stipe. Factors required for each stage differed. At the stipe elongation stage, low temperature (10°/5°C; day/night) and high humidity were important, but light was not required. In contrast, at the fertile head stage, light and moderate day length (8h/day) were essential. Fertile heads developed at 46µEm–2s–1; and high intensity (137µEm–2s–1) did not suppress development. Moreover, adding unsterilized soil to the sea sand medium accelerated sporocarp formation. These findings imply that the sclerotium of T. ishikariensis recognizes several physical factors for sporocarp formation. Sporocarps of T. ishikariensis developed within 4 weeks after incubation under optimal conditions. The sporocarp produced basidiospores, and differential mating incompatibility was confirmed among monokaryons derived from basidiospores produced under artificial conditions. This method should be useful for obtaining monokaryons for genetic studies of T. ishikariensis. 相似文献
98.
Kurata K Iwata A Masuda K Sakaguchi M Ohno K Tsujimoto H 《Veterinary immunology and immunopathology》2004,102(4):441-450
Oligodeoxynucleotides containing the cytosine-phosphate-guanine (CpG) motif (CpG-ODNs) have been shown to induce T(H)1 immune responses in animals. Since the sequences of CpG-ODNs that induce T(H)1 responses are considered to vary among animal species, it is necessary to identify effective CpG-ODNs in each animal. In order to identify the sequences of CpG-ODNs that induce T(H)1 responses in dogs, mRNA expression and protein production of IFN-gamma were examined in peripheral blood mononuclear cells (PBMCs) from healthy dogs treated with 11 kinds of synthetic CpG-ODNs. One of the 11 CpG-ODNs (No. 2 CpG-ODN, 5'-GGTGCATCGATGCAGGGGGG-3') was shown to significantly increase mRNA expression and protein production of IFN-gamma in canine PBMCs in a manner dependent on the sequence of the CpG motif. This CpG-ODN also enhanced the expression of IL-12 p40 mRNA in canine PBMCs, whereas expression of IL-12 p35, IL-18, and IL-4 mRNAs was not induced by this CpG-ODN. These results indicate that this CpG-ODN was able to produce IFN-gamma by induction of T(H)1-skewed immune response in dogs. CpG-ODNs may be useful for inducing prophylactic and therapeutic immunity against allergic diseases, viral infection, and tumors in dogs. 相似文献
99.
Maruyama H Miura T Sakai M Koie H Yamaya Y Shibuya H Sato T Watari T Takeuchi A Tokuriki M Hasegawa A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(5):573-575
The incidence of DIC in 208 dogs with a malignant tumor was evaluated. The incidence of DIC was 9.6% in dogs with a malignant tumor which was a solid tumor in all. In 164 dogs with a malignant solid tumor, the incidence of DIC was 12.2%. The incidence of DIC in dogs with hemangiosarcoma, mammary gland carcinoma and adenocarcinoma of the lung was significantly higher than that in dogs with other malignant tumors. These results suggested that special care in looking for DIC should be taken in dogs with a malignant solid tumor. 相似文献
100.
Fukushima R Ichikawa K Hirabayashi M Yamagami T Koyama H Hirose H Uchino T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(8):993-995
The dog of this case was a 10-year-old Shih Tzu with refractory vomiting, diarrhea and anorexia. Endoscopy revealed an unclear at gastric angle, a stenosis at pyloric antrum and congestion in duodenal mucosa. Since abnormal shadows of irregular echo-levels were disclosed by pancreas ultrasonography, serum gastrin level was determined with a suspect of gastrinoma. And an increase of serum gastrin was demonstrated. In addition, postmortem histological examination revealed that the pancreatic cells were positive for gastrin. Based on these findings, the dog was diagnosed as pancreatic gastrinoma. 相似文献