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91.
This paper reports the results of reproduction with 45 wild African green monkeys (Cercopithecus aethiops) (36 females and 9 males) during the nine years from 1981 to 1989 under indoor individually-caged conditions. In 206 cases of menstruation observed, menstrual discharge lasted for 2.5 +/- 1.2 days in cycles of 22-48 days, and the length of each menstrual cycle was 31.2 +/- 6.5 days. Females who had regular menstrual cycles were subjected to "one-to-one timed mating"; females and males were put together on a one-to-one basis daily only for a certain period of time on and after the day of ovulation. Females who had irregular menstrual cycles or had no menstruation were subjected to "every-other-day mating"; females and males were put together on a one-to-one basis every other day for at least 16 weeks. The pregnancy rate (No. of pregnant females/No. of mated females) by one-to-one timed mating was 48.9% (116/237); 2.0 mating trials were needed to obtain one case of pregnancy. On the other hand, the pregnancy rate (No. of pregnant females/No. of mating trials) by every-other-day mating was 96% (48/50). Females who delivered normally totaled 129. The mean gestation period was 165 days when males, weighing 343 g on average at birth, were delivered, and 166 days when females, weighing 318 g on average at birth, were delivered. The male and female newborns were nursed for 131 and 138 days, respectively, on average. Details are summarized in Table 3. This paper also reports 23 cases of abortion, 6 stillbirths, and 6 cases of Caesarean section, by which three live fetuses and three dead fetuses were obtained. 相似文献
92.
中国脊髓灰质炎Ⅱ型疫苗相关分离株病毒性状的观察 总被引:7,自引:1,他引:7
对1994年中国分离的13株脊髓灰质炎Ⅱ型疫苗相关株进行了PCR-RFLP分析,发现7株为重组病毒,毒力较疫苗株有回复,在Ⅱ型脊髓灰质炎病毒基因序列上,对于神经毒力有重要影响的第481位核苷酸发生突变,另一个被视为重要位点的2908位核苷酸无一发生变化,反而在2909位核苷发生了高频率的点突变,意味着2909位点在中国Ⅱ型疫苗相关株的自然变异中可能起着重要作用。 相似文献
93.
Concentration and Membrane Fluidity Dependence of Odor Discrimination in the Turtle Olfactory System 总被引:1,自引:0,他引:1
Kashiwayanagi Makoto; Sasaki Kazuyo; lida Akio; Saito Hanako; Kurihara Kenzo 《Chemical senses》1997,22(5):553-563
In the present study, we examined the concentration dependenceof odor discrimination in turtle olfactory bulbar responsesusing the cross-adaptation technique. In the odorant pairs withdiverse molecular structures, the degree of discrimination wasunchanged or only slightly decreased with an increase in odorantconcentrations, suggesting that odorants are well discriminatedeven at high concentrations. In the odorant pairs with closelyrelated molecular structures, the degree of discrimination wasdecreased with an increase in odorant concentrations. An increasein the temperature of turtle olfactory epithelium also decreasedthe ability to discriminate these odorants. There was a goodcorrelation between changes in the odor discriminating abilityinduced by an increase in odor concentrations and those inducedby a temperature increase. The liposomes were made of lipidsextracted from the turtle olfactory epithelia and changes oftheir membrane fluidity induced by adsorption of odorants weremonitored with DPH. There was a good correlation between a decreasein odor discriminating ability and the membrane fluidity changesinduced by odorants. We suggest that decreases in odor discriminatingability induced either by an increase in odor concentrationor by a temperature increase are ultimately caused by changesin the membrane fluidity. Chem. Senses 22: 553563, 1997. 相似文献
94.
Harada KH Ishii TM Takatsuka K Koizumi A Ohmori H 《Biochemical and biophysical research communications》2006,351(1):240-245
Recently, PFOS was reported to be ubiquitously detected in the environment, as well as in human serum, raising concerns regarding its health risks. We investigated the effects of PFOS on action potentials and currents in cultured rat cerebellar Purkinje cells using whole-cell patch-clamp recording. In current-clamp experiments, PFOS significantly decreased the action potential frequency during current injection, the maximum rate of fall and the threshold of action potential, and negatively shifted the resting membrane potential at doses over 30microM. In voltage-clamp experiments, PFOS shifted the half-activation and inactivation voltages of I(Ca), I(Na), and I(K) toward hyperpolarization at 30microM. I(HCN1) expressed in Xenopus oocytes was similarly affected. Incorporation of PFOS into the cell membrane probably increased the surface negative charge density, thereby reducing the transmembrane potential gradient and resulting in hyperpolarizing shifts of both the activation and inactivation of ionic channels. These findings indicate that PFOS may exhibit neurotoxicity. 相似文献
95.
Md. Kamruzzaman Sahadev Sharma Mouctar Kamara Akio Hagihara 《Wetlands Ecology and Management》2013,21(4):277-288
The vegetative and reproductive phenology of the subtropical mangrove species Rhizophora stylosa was investigated at Manko Wetland, Okinawa Island, Japan. We assessed phenology using litterfall data over four years. Leaf and stipule litterfall occurred throughout the year, with distinct seasonal patterns. Kendall’s coefficient of concordance, W, revealed that the monthly changes in leaf and stipule litterfall were strongly and significantly concordant among years. Leaf litterfall was significantly correlated with monthly maximum wind speed and monthly day length, and stipule litterfall was significantly correlated with monthly mean air temperature and relative humidity. Branch litterfall showed no clear monthly pattern and correlated well with monthly maximum wind speed. Mean total litterfall was 11.2 Mg ha?1 year?1, with the largest component being vegetative organs (78.7 %). Flower, fruit, and propagule litterfall were all highest in summer and lowest in winter. The W values revealed that most reproductive organs in litterfall had significant monthly trends. Flower and fruit litterfall were significantly correlated with monthly day length and monthly mean air temperature, respectively. The average development periods from flower buds to flowers, fruits, and mature propagules were approximately 2–3 months, 4–5 months, and 11–12 months, respectively. Except for branches, all vegetative and reproductive components of litterfall had approximately one year cycles. 相似文献
96.
Akio Nobuhara 《Bioscience, biotechnology, and biochemistry》2013,77(9):1264-1269
6-Pentyl-α-pyrone, 6-propyl-α-pyrone and 4-decenoic acid-δ-lactone were prepared, and the nature of their flavors was investigated. Unsaturated lactones having the best flavorous nature as a butter or butter cake flavor among the lactones having double bond at various site, were 2-ene-δ-lactones which have a double bond at the α-position of the lactone ring and α-pyrones which have two double bonds at the α- and γ-positions. The flavor of 4-deceno-δ-lactone which has a double bond at the γ-position was the worst of them. 相似文献
97.
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99.
The in vitro activity of several new imidazoles, cloconazole, sulconazole, butoconazole, isoconazole and fenticonazole, were compared with those of amphothericin B, flucytosine, and three azoles: econazole, miconazole and ketoconazole against isolates of pathogenic Candida. A total of 186 clinical isolates of 10 species of the genus Candida and two culture collection strains were tested by an agar-dilution technique. Isoconazole was the most active azole, followed by butoconazole and sulconazole. Differences between some of the species in their susceptibility to the antifungal agents were noted. Sulconazole and cloconazole had the highest activity in vitro against 106 isolates of C. albicans. Butoconazole and isoconazole were also very active against isolates of C. albicans, and were the most active azole compounds against 80 isolates of Candida spp. 相似文献
100.