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411.
The circadian rhythm of air-borne bacteria and dust particles in a mice breeding room was studied at 1-hour intervals on the first, third and fifth day after accommodation of the animals. The numbers of air-borne bacteria in the room increased day by day after accommodation, and showed a circadian rhythm which went down at about noon and rose with three peaks at about 20:00, 1:00 and 8:00. The numbers of dust particles tended to decrease from day to day, and they showed almost the same circadian rhythm as the air-borne bacteria. Correlations between air-borne bacteria and dust particles were not significant for each particle level on the first day, but were significant for all the particle levels of 0.3, 1, 2, and 5 microns at the third day, and were also significant at particles levels of 0.5 micron or more on the fifth day.  相似文献   
412.
A new spironucleoside structural type and two new bicyclic nucleoside structural types were synthesized from the reaction of ribose nitrile oxide with dimethyl acetylenedicarboxylate. Next, a synthetic method for novel meso-ionic nucleoside structual type is presented.  相似文献   
413.
Biomechanics and Modeling in Mechanobiology - The seeding of cells into an organ is an important step in cell therapy because the final functional properties of the organ are related to...  相似文献   
414.
Cell wall-associated β-xylosidase was isolated from Aspergillus niger E-1 and identified as XlsIV, corresponding to the extracellular enzyme XlnD reported previously. xlsIV was transcribed only in the early cultivation period. Cell wall-associated enzyme activity gradually decreased, but extracellular activity increased as the strain grew. These results indicate that XlsIV (XlnD) was secreted into culture after localizing at cell wall.  相似文献   
415.
To determine whether workers engage in trophallactic behavior preferentially toward highly related nestmates, we examined these behaviors between workers in colonies consisting of both kin and non-kin (mixed colony) and of only kin (pure colony). These behaviors were observed under sufficiently fed and in both starvation and normal feeding conditions. Workers in mixed colonies exhibited trophallactic behaviors equally toward kin and non-kin in both experimental conditions. The frequency of trophallaxis between workers in mixed colonies, however, tended to be lower than that in pure colonies, is especially under starvation conditions. The low frequency of trophallaxis among workers discussed in terms of the low degree of genetic relatedness among nestmates in mixed colonies.  相似文献   
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Melanocortin peptides have been reported to influence opiate tolerance, but the neuronal basis underlying these actions is unknown. We studied the contribution of melanocortin (MC4R) receptors to morphine effects. The MC4R mRNA level in the amygdala was decreased after acute morphine treatment and increased in rats tolerant to morphine as evidenced by quantitative real-time PCR method. Moreover, the intra-amygdalar microinjection of antagonist of MC4R attenuated morphine tolerance. Expression of the spinal MC4R after sciatic nerve injury was decreased in the early phase of neuropathy and slightly decreased 2–3 weeks after injury. These findings suggest that the altered melanocortin receptor function may contribute to the development of morphine-induced effects. Thus, the melanocortin receptors may be a target for development of better and more effective drugs for the therapy of chronic pain.
Acknowledgement:  Supported by KBN grant for the statutory activity.  相似文献   
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An epidemic of pharyngoconjunctival fever due to adenovirus type 3 occurred among children in a primary school in Japan during summer months of 1964. The etiologic diagnosis of the epidemic was readily made by virus isolation and serologic tests on patients. Adenovirus type 3 was isolated in HeLa cell cultures from 55% of 52 patients, and serologic evidence for type 3 virus infection was obtained in 93% of 54 patients which were tested for complement-fixing, neutralizing, and hemagglutination-inhibiting antibodies. The HI test was found to be as useful in the serologic diagnosis of the serotype as the NT test. It is evident that for the routine use, the HI test is more advantageous than NT test as the latter is more laborious and time consuming. The fact that a strain recovered in this epidemic gave higher HI titers than the prototype strain, when used as the antigen in HI tests with sera of patients in this epidemic indicates the desirability of selecting an appropriate virus strain for preparation of the antigen for HI test in serological diagnosis of patients.  相似文献   
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