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11.
Kitamura Akira; Matsui Kenji; Kajiwara Tadahiko; Hatanaka Akikazu 《Plant & cell physiology》1992,33(4):493-496
C6-Aldehydes emitted from intact tea leaves were analyzed quantitatively.Emission of the aldehydes increased temporarily in mid-May whenenzymatic activities involved in aldehyde formation from lipidsbegan to increase. Levels of C6-aldehydes in tea leaves alsoincreased temporarily. However, the accumulated C6-aldehydesdid not always correspond to emitted ones. (Received December 1, 1991; Accepted March 18, 1992) 相似文献
12.
Kenji Matsuura 《Oikos》2001,92(1):20-26
Discrimination and aggressive responses toward non-nestmates have been observed in a number of termite species, but the mechanism is poorly understood. Here I present the novel hypothesis that differential intestinal bacteria composition leads to production of colony-specific chemical cues that enable nestmate recognition.
The intestinal microflora of a lower termite, Reticulitermes speratus , consisted of many bacteria species. The composition of the intestinal bacteria was exclusively colony-specific. Termites that had adsorbed an unfamiliar odor of bacteria sampled from another colony were fiercely attacked by nestmates. Experimental manipulation of the composition of bacteria by antibiotics successfully changed the recognition behavior toward nestmates. These results indicate that intestinal bacteria play an important role in nestmate recognition. 相似文献
The intestinal microflora of a lower termite, Reticulitermes speratus , consisted of many bacteria species. The composition of the intestinal bacteria was exclusively colony-specific. Termites that had adsorbed an unfamiliar odor of bacteria sampled from another colony were fiercely attacked by nestmates. Experimental manipulation of the composition of bacteria by antibiotics successfully changed the recognition behavior toward nestmates. These results indicate that intestinal bacteria play an important role in nestmate recognition. 相似文献
13.
Kenji Masumoto Tomoki Shono Shin-ichiro Takasugi Noboru Hotta Kazutaka Fujishima Yukihide Iwamoto 《Journal of electromyography and kinesiology》2007,17(5):596-604
This study aimed to examine whether walking in water produces age-related differences in muscle activity, stride frequency (SF), and heart rate (HR) response. Surface electromyography (EMG) was used to evaluate muscle activities in six older and six young subjects while they walked in water immersed to the level of the xiphoid process. The trials in water utilized the Flowmill which consists of a treadmill at the base of a water flume. The measurement of maximal voluntary contraction (MVC) of each muscle was made prior to the gait analysis. The %MVCs, which refer to the surface EMG measures, from the gastrocnemius of the older subjects were significantly lower than those of the young subjects, in every experimental condition (P<0.05). In contrast, the %MVCs from the rectus femoris (P<0.05) and the biceps femoris (P<0.001) of older subjects were significantly greater than those of young subjects in every experimental condition. Moreover, the SFs of older subjects were also significantly greater than those of young subjects (P<0.05), while the HR responses of older and young subjects were similar. In conclusion, the older subjects had increased hip musculature activity and decreased ankle plantar flexor activity while walking in water, compared with the young subjects. 相似文献
14.
15.
Yoshiki Takashima Hiroki Nakajima Kenji Sonomoto Atsuo Tanaka 《Applied microbiology and biotechnology》1987,27(2):106-109
Summary
Streptomyces peucetius cells were immobilized by entrapment in calcium alginate and a photosensitive synthetic polymer, and used for the production of daunorubicin (daunomycin), which is known to be an antitumour reagent. The use of cultivation media removed insoluble components in a natural medium prevented rapid decrease in daunorubicin titer after maximum production. These entrapped cells could be used at least five times for repeated daunorubicin production; the total cultivation period was 45 days. 相似文献
16.
The role of phospholipase in beta-agonist-induced down regulation in guinea pig lungs 总被引:2,自引:0,他引:2
K Suzuki S Sugiyama K Takagi T Satake T Ozawa 《Biochemical medicine and metabolic biology》1987,37(2):157-166
It has been observed that repeated and prolonged beta-agonist treatment causes the impairment of beta-adrenergic function, so-called "desensitization" or "down regulation". To clarify the mechanism of down regulation, the following experiment was performed using guinea pig lungs. Animals were divided into four groups: In the metaproterenol groups, guinea pigs were treated with metaproterenol (10 mg/kg/day) by intraperitoneal injection once a day for 1 day or for 7 successive days In the control groups, guinea pigs were treated with saline by the same procedure as in the metaproterenol groups. In the group treated with metaproterenol for 7 days, there was a 45% reduction in the number of beta-adrenoceptors and a 62% reduction in adenylate cyclase activity, compared with those of the control group. However, there were no significant changes in the dissociation constant (Kd) of the receptors. On the other hand, no reduction in the number of beta-adrenoceptors and adenylate cyclase activity was observed in the group treated with metaproterenol once a day for 1 day, compared with those of the control group. Phospholipase (PLase) activity in the lung microsomes of guinea pigs injected with metaproterenol for 1 day and for 7 days was elevated by 14.4 and 33.1%, respectively, compared with that of the control groups. Phospholipid contents of lung membranes prepared from the animals treated with metaproterenol for 7 days were significantly decreased compared with those of the control group, though in the group treated with metaproterenol once a day for 1 day, phospholipid contents did not differ from those of the control. Lung membranes treated with PLase A2 revealed decreases both in the number of beta-adrenoceptors and adenylate cyclase activity, dose dependently. These results and the fact that membrane phospholipids are involved in the beta-adrenoceptor system suggest that down regulation observed during beta-agonist administration is, at least in part, attributed to degradation of phospholipids of lung membranes by the persistent activation of PLase in the tissue. 相似文献
17.
18.
Masayuki Sasaki Kenji Sugio Jun-Ichi Soejima Tatsuro Ikeuchi Akira Tonomura Takeo Iwama Joji Utsunomiya Takehiko Sasazuki 《Human genetics》1987,77(1):36-39
Summary We investigated possible association of and linkage between HLA and familial polyposis coli (FPC). In 182 individuals from 66 pedigrees of FPC and 108 individuals from a normal population, HLA-A,-B, and-C antigens were determined. When the frequencies of HLA antigens in 66 unrelated patients and in normal controls were compared, no association of FPC with HLA was observed. For the linkage analysis, HLA haplotypes of 17 affected sib pairs were investigated by the affected sib pair method. The number of pairs which shared two, one, and no haplotypes identical by descent was not significantly different from the number expected with random occurrence (P>0.95). Finally, seven families were analyzed using Morton's sequential test. A maximum lod score of-0.056 at a recombination fraction of 0.4, and a lod of-3.089 at a recombination fraction of 0.05 were obtained. Therefore, there is neither an association of nor linkage between FPC and HLA. 相似文献
19.
Neonatal polycythemia is a perinatal complication in infants of diabetic mothers. The cord CBC (complete blood counts), serum iron, transferrin and ferritin concentrations were studied in newborn infants of 9 GDM (gestational diabetes), 21 NIDDM (noninsulin-dependent diabetes mellitus), and 8 IDDM (insulin-dependent diabetes mellitus) mothers. The RBC (red blood cell) count, Hb (hemoglobin) and Hct (hematocrit) of these infants were higher than control infants. There was no difference between the serum iron concentration of the infants of each group diabetic mothers and the infants in the control group, but the transferrin concentration was significantly higher and the ferritin was significantly lower in the infants of diabetic mothers than in those of control mothers. There was a significant negative correlation between transferrin and ferritin (r = -0.491 p less than 0.001). Erythropoiesis is considered to be enhanced in the fetuses of diabetic mothers, and the iron needed for erythropoiesis is reportedly transported from the mother to the fetus according to the demands of the fetus, but the iron storage was shown to be reduced in the fetuses of diabetic mothers. 相似文献
20.
Eight-week-old, female Wistar fatty rats and their lean littermates were given a 30% sucrose solution in addition to a laboratory chow diet and water for 7 weeks. The fatty rats were hyperinsulinemic and hyperlipidemic, but normoglycemic when they drank only water. The hepatic activities of insulin-inducible glucokinase (GK), pyruvate kinase (PK), and malic enzyme (ME) were higher in the fatty rats than in the lean rats, whereas the insulin-suppressible glucose-6-phosphatase (G6Pase) activity was similar in both types of rats, indicating the normal response of hepatic enzymes to hyperinsulinemia in the fatty rats. When they drank the sucrose solution, the fatty rats, but not the lean rats, developed hyperglycemia over 200 mg/dl. Plasma insulin and triglyceride concentrations increased in both types of rats. Although the hepatic activities of GK, PK, and ME in the lean rats, and PK and ME in the fatty rats increased in response to the increase in plasma insulin, GK activity decreased in the fatty rats. On the other hand, G6Pase activity increased in both types of rats. As a result, the G6Pase/GK ratio, which may reflect net glucose handling in the liver, increased twofold in the fatty rats, but did not alter in the lean rats. From these findings, we conclude that sucrose ingestion induces an increase in hepatic glucose production through derangement of the hepatic enzyme profile and that the resultant decrease in hepatic glucose handling may be one of the pathogenic factors participating in the development of hyperglycemia in Wistar fatty rats. 相似文献