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61.
The liverwort Marchantia polymorpha has become one of the model organisms, since it has less genetic redundancy, sexual and asexual modes of reproduction and a range of genomic and molecular genetic resources. Cryopreservation of fertile spermatozoa eliminates time, space and labor for growing and maintaining male plants in reproductive phase, and also provides an optional way to backup lines. Here we report a protocol to cryopreserve spermatozoa of M. polymorpha in liquid nitrogen. A cryoprotective solution containing sucrose, glycerol and egg yolk and controlled cooling and warming processes led to successful recovery of motile M. polymorpha spermatozoa after the cryogenic process. The survival rate and average motility of spermatozoa after cryopreservation were maintained at 71 and 54% of those before cryopreservation, respectively. Cryopreserved spermatozoa were capable of fertilization to form normal spores. The technique presented here confers more versatility to experiments using M. polymorpha and could be applied to preservation of plant spermatozoa in general.  相似文献   
62.
Ewing's sarcoma is a recalcitrant tumor greatly in need of more effective therapy. The aim of this study was to determine the efficacy of eribulin on a doxorubicin (DOX)‐resistant Ewing's sarcoma patient derived orthotopic xenograft (PDOX) model. The Ewing's sarcoma PDOX model was previously established in the right chest wall of nude mice from tumor resected form the patient's right chest wall. In the previous study, the Ewing's sarcoma PDOX was resistant to doxorubicin (DOX) and sensitive to palbociclib and linsitinib. In the present study, the PDOX models were randomized into three groups when the tumor volume reached 60 mm3: G1, untreated control (n = 6); G2, DOX treated (n = 6), intraperitoneal (i.p.) injection, weekly, for 2 weeks); G3, Eribulin treated (n = 6, intravenous (i.v.) injection, weekly for 2 weeks). All mice were sacrificed on day 15. Changes in body weight and tumor volume were assessed two times per week. Tumor weight was measured after sacrifice. DOX did not suppress tumor growth compared to the control group (P = 0.589), consistent with the previous results in the patient and PDOX. Eribulin regressed tumor size significantly compared to G1 and G2 (P = 0.006, P = 0.017) respectively. No significant difference was observed in body weight among any group. Our results demonstrate that eribulin is a promising novel therapeutic agent for Ewing's sarcoma.  相似文献   
63.
This study evaluated the impact of the thermal environment on the flying behavior of male Japanese sulfur butterflies Colias erate searching for females in an open habitat. Thoracic temperature was monitored before and after flight. Mean thoracic temperature of butterflies immediately after landing was consistently higher than, but independent of, ambient temperature. Although ground speed of flying butterflies was different between flight types, air speed against the butterfly was similar across flight types. The excess of thoracic over ambient temperature was lower in flying butterflies than in basking ones, as predicted by a model. This difference appeared to be due to air current, which enhanced heat loss. In a laboratory study, newly eclosed male butterflies were placed under an incandescent lamp to measure their thoracic temperature at different air current speeds. The excess of thoracic over ambient temperature decreased as the speed of air currents increased. When the air current was similar to the air speed against flying butterflies in the field, a substantial decrease occurred in the operative thoracic temperature.  相似文献   
64.
Individual variations of 1-antitrypsin of the macaques were investigated by means of starch gel electrophoresis. The material comprised a total of 1,084 plasma samples taken from six species, namely,Macaca irus, mulatta, cyclopis, nemestrina, speciosa, andfuscata, including several geographical groups. At least ten phenotypes which were assumed in analogy to human Pi-system to be under genetic control of five codominant alleles tentatively denoted byPi Mac A, B, C, D, E were identified. It was considered that these alleles are commonly possessed by different macaque species. A marked difference in the distribution of allele frequencies was found both within and between species groups. Several aspects of this new polymorphic variation in the macaques were discussed with special reference to the geographical distribution of the alleles and the origins of the Japanese macaque,M. fuscata. This study was carried out as part of the Special Project of the Japan-U.S. Cooperative Scientific Program: Blood Macromolecules and the Genetic Origins of the Japanese Macaques (Chief investigators:T. Miki andM. Goodman)  相似文献   
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66.
Bactrocera carambolae and B. dorsalis (Diptera: Tephritidae) are extremely destructive pests of fruits and vegetables in the Asia-Pacific region. Earlier reports have described that B. carambolae and B. dorsalis, respectively, use mainly star fruit and mango, suggesting a certain level of host partitioning which can be ascribed neither to differences in larval food qualities nor host-specific parasitoid mortality. This study specifically examined reproductive interference (antagonistic sexual interaction) between B. carambolae and B. dorsalis as a potential factor strongly affecting their host partitioning. We observed mating behaviors, especially interspecific courtships and mating, by cohabiting the conspecific and heterospecific pairs together. Consequently, we quantified their effects on the reproductive success of females. Males of both species frequently courted their own females, but they also courted females of other species. Courtship refusal by females was not selective in males of either species. This incomplete discrimination of both sexes led to frequent occurrences of interspecific sexual interactions in both species, but only B. carambolae females showed reduced reproductive success. These results suggest that B. dorsalis, superior in reproductive interference, can occupy high-quality mango, whereas B. carambolae, inferior in reproductive interference, must use low-quality star fruit.  相似文献   
67.
The detailed segregative cell division (SCD) processes and changes in the arrangement of cortical microtubules and actin filaments were examined in two species of Struvea. SCD was initiated by the appearance of annular constrictions along the lateral side of a mother cell. The constrictions decreased in diameter, became thin, tubular in shape, and pinched the protoplasm of the mother cell into several protoplasmic sections. The protoplasmic sections expanded and developed into daughter cells, which appressed each other, and were arranged in a single row. Lateral branches protruded from the upper parts of the daughter cells. The protoplasm of the lateral branches was divided by secondary SCDs and was distributed amongst the new daughter cells. SCD and lateral branch formation were essential for morphogenesis in Struvea. Cortical microtubules were arranged parallel and longitudinally to the cell axis before SCD. When SCD was initiated, there was considerable undulation of the cortical microtubules and several transverse bundles appeared in the cytoplasmic zone where annular constrictions occurred. A microtubule‐disrupting drug (amiprophos methyl) inhibited SCD. Actin filaments maintained reticulate patterns before and during SCD. These results demonstrated that SCD in Struvea species was quite distinct from that in Dictyosphaeria cavernosa reported previously.  相似文献   
68.
本文报道了父母双方上溯三代均为畲族的123名健康人的9个红细胞血型系统的分布。其表型分布如下:ABO血型系统:A型34人,B型26人,O型57人,AB型6人。MNSs血型系统:MNSs型5人,MMSs型5人,NNSs型1人, MMss型32人,MNss型62人,NNss型18人。未发现SS型。Rh血型系统:CCDee型44人,CcDee型9人,CCDEe型5人, CcDEe型55人,ccDEe型2人,ccDEE型8人,未发现ccDee、CCDEE型及CcDEE型。Duffy血型系统:Fy(a+b-)型115人,Fy(a+b+)型8人,未发现Fy(a-b+)及Fy(a-b-)型。 Kidd血型系统:Jk(a+b-)型49人,Jk(a+b+)型43人,Jk(a+b+)型43人,Jk(a-b+)型31人,未发现Jk (a-b-)型。Lutheran血型系统: Lu(a-b+) 型123人,未发现Lu(a+b-)及Lu(a+b+)型。Diego血型系统:Di(a+)型13人,Di(a-)型110人。P血型系统:P1(+)型38人,P1(-)型85人。Lewis血型系统:Le(a+b-)型16人,Le(a+b+)型9人,Le(a-b+)型91人,Le(a-b-)型7人。  相似文献   
69.
70.
Based on the morphological characteristics of the skull and teeth, Hanihara ([1991] Japan Review 2:1–33) proposed the “dual structure model” for the formation of modern Japanese populations. We examine this model by dividing it into two independent hypotheses: 1) the Upper Paleolithic population of Japan that gave rise to the Neolithic Jomon people was of southeast Asian origin, and 2) modern Ainu and Ryukyuan (Okinawa) populations are direct descendants of the Jomon people, while Hondo (Main Island)-Japanese are mainly derived from the migrants from the northeast Asian continent after the Aeneolithic Yayoi period. Our aim is to examine the extent to which the model is supported by genetic evidence from modern populations, particularly from Japan and other Asian areas. Based on genetic distance analyses using data from up to 25 “classic” genetic markers, we find first that the three Japanese populations including Ainu and Ryukyuan clearly belong to a northeast Asian cluster group. This negates the first hypothesis of the model. Then, we find that Ainu and Ryukyuans share a group contrasting with Hondo-Japanese and Korean, supporting the second hypothesis of the model. Based on these results, we propose a modified version of the dual structure model which may explain the genetic, morphological, and archaeological evidence concerning the formation of modern Japanese populations. Am J Phys Anthropol 102:437–446, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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