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991.
992.
993.
Shinsuke IDEO Masayoshi WATADA Hideyuki MITSUI Masahito T. KIMURA 《Entomological Science》2008,11(1):1-6
We studied the host range of Asobara japonica, a larval‐pupal parasitoid of drosophilid flies. Habitat selection was found to be an important determinant of host range in this parasitoid; it attacked drosophilid larvae breeding on banana and mushrooms, but seldom attacked those breeding on decayed leaves. This parasitoid was able to use diverse drosophilid taxa as hosts. Attack by A. japonica sometimes killed hosts at the larval stage, and therefore parasitoid larvae also died. Drosophila elegans and D. busckii suffered particularly high larval mortality due to the attack by A. japonica (in the latter species only when young larvae were attacked). Many individuals of D. subpulchrella also died at the pupal stage without producing parasitoids when they were parasitized at the late larval stage. In contrast, D. bipectinata, D. ficusphila, D. immigrans, D. formosana and D. albomicans were resistant to attack: large proportions of the larvae of these drosophilid species grew to adulthood, even in the presence of parasitoids. On the basis of phylogenetic information, we concluded that phylogenetic position has only limited importance as a factor determining whether a species is suitable as a host for A. japonica, at least within the genus Drosophila. 相似文献
994.
The mechanism of a new hypoglycemic agent, AS-6, was comparatively studied using the adipocytes from AS-6 treated and untreated genetically obese diabetic mice, db/db. the db/db mice were treated for 1 week with a diet admixture of AS-6 (0.1%). The treatment resulted in the following alterations in metabolic activities; AS-6 treatment increased 125I-insulin binding by 1.4-3.3 fold over the insulin range of 1-1000 microU/ml, the treatment increased the basal activities in 2-deoxyglucose uptake, and in CO2 generation and lipogenesis from U-(14C)-glucose compared with the db/db controls, the treatment partially restored insulin responsiveness in 2-DG uptake and CO2 generation, and 1 mU/ml of insulin greatly stimulated lipogenesis by 5.6 fold above the basal in the control adipocytes while AS-6 treatment changed the lipogenic response less stimulative to the insulin. The results suggest that AS-6 treatment significantly increases insulin binding to the adipocytes associating with an enhancement in glucose metabolism under basal and physiological concentrations of insulin. 相似文献
995.
996.
In Vitro Validation of an Artefact Suppression Algorithm in X-Ray Phase-Contrast Computed Tomography
X-ray phase-contrast tomography can significantly increase the contrast-resolution of conventional attenuation-contrast imaging, especially for soft-tissue structures that have very similar attenuation. Just as in attenuation-based tomography, phase contrast tomography requires a linear dependence of aggregate beam direction on the incremental direction alteration caused by individual voxels along the path of the X-ray beam. Dense objects such as calcifications in biological specimens violate this condition. There are extensive beam deflection artefacts in the vicinity of such structures because they result in large distortion of wave front due to the large difference of refractive index; for such large changes in beam direction, the transmittance of the silicon analyzer crystal saturates and is no longer linearly dependent on the angle of refraction. This paper describes a method by which these effects can be overcome and excellent soft-tissue contrast of phase tomography can be preserved in the vicinity of such artefact-producing structures. 相似文献
997.
Masaru Wakatsuki Shingo Kato Hiroki Kiyohara Tatsuya Ohno Kumiko Karasawa Tomoaki Tamaki Ken Ando Hirohiko Tsujii Takashi Nakano Tadashi Kamada Makio Shozu The Working Group of the Gynecological Tumor 《PloS one》2015,10(5)
To evaluate the efficacy and the toxicity of prophylactic extended-field carbon-ion radiotherapy (C-ion RT, Protocol 0508) for locally advanced squamous cell carcinoma of the uterine cervix in phase I / II clinical trial. Between May 2006 and January 2012, 26 patients of Protocol 0508 were treated with C-ion RT. The numbers of patients with stage IIB, IIIB, and IVA disease were 13, 11, and 2, respectively. Twenty patients had pelvic lymph node metastases. Median tumor size was 6.1 cm (range, 4.0–10.0 cm). The treatment consisted of extended-field irradiation of 39.0 gray equivalents (GyE) in 13 fractions, and additional 15.0 GyE in 5 fractions was given to the gross tumor volume (GTV) and surrounding tissues. With regard to local boost, 18.0 GyE in 2 fractions was given to GTV only. Total dose to the cervical tumor was 72.0 GyE over 20 fractions. The median follow-up period was 37 months. Twenty-one patients had grade 1 or 2 acute gastrointestinal toxicity, but all patients completed the treatment on schedule. There were no grade 3 or higher late complications, with 8 patients having grade 1 or 2 toxicities, 1 had grade 2 gastrointestinal toxicity and 2 had grade 2 genitourinary toxicity. Four patients (15.4%) developed local recurrence, and 8 patients (30.8%) had distant metastases. The 2-year local control rate, progression-free survival rate and overall survival rate were 83.6%, 61.5% and 73.1%, respectively. There were no severe acute or late complications in this trial. Prophylactic extended-field C-ion RT for locally advanced squamous cell carcinoma of the uterine cervix was a safe treatment. Although the number of patients in this study was small, the results support further investigations to confirm the therapeutic efficacy and to avoid or reduce toxicity.
Trial Registration
UMIN-CTR UMIN000016169 相似文献998.
Masahiro Nakatochi Yasunori Ushida Yoshinari Yasuda Yasuko Yoshida Shun Kawai Ryuji Kato Toru Nakashima Masamitsu Iwata Yachiyo Kuwatsuka Masahiko Ando Nobuyuki Hamajima Takaaki Kondo Hiroaki Oda Mutsuharu Hayashi Sawako Kato Makoto Yamaguchi Shoichi Maruyama Seiichi Matsuo Hiroyuki Honda 《PloS one》2015,10(2)
Although many single nucleotide polymorphisms (SNPs) have been identified to be associated with metabolic syndrome (MetS), there was only a slight improvement in the ability to predict future MetS by the simply addition of SNPs to clinical risk markers. To improve the ability to predict future MetS, combinational effects, such as SNP—SNP interaction, SNP—environment interaction, and SNP—clinical parameter (SNP × CP) interaction should be also considered. We performed a case-control study to explore novel SNP × CP interactions as risk markers for MetS based on health check-up data of Japanese male employees. We selected 99 SNPs that were previously reported to be associated with MetS and components of MetS; subsequently, we genotyped these SNPs from 360 cases and 1983 control subjects. First, we performed logistic regression analyses to assess the association of each SNP with MetS. Of these SNPs, five SNPs were significantly associated with MetS (P < 0.05): LRP2 rs2544390, rs1800592 between UCP1 and TBC1D9, APOA5 rs662799, VWF rs7965413, and rs1411766 between MYO16 and IRS2. Furthermore, we performed multiple logistic regression analyses, including an SNP term, a CP term, and an SNP × CP interaction term for each CP and SNP that was significantly associated with MetS. We identified a novel SNP × CP interaction between rs7965413 and platelet count that was significantly associated with MetS [SNP term: odds ratio (OR) = 0.78, P = 0.004; SNP × CP interaction term: OR = 1.33, P = 0.001]. This association of the SNP × CP interaction with MetS remained nominally significant in multiple logistic regression analysis after adjustment for either the number of MetS components or MetS components excluding obesity. Our results reveal new insight into platelet count as a risk marker for MetS. 相似文献
999.
Masayoshi Tokita 《Biological reviews of the Cambridge Philosophical Society》2015,90(4):1163-1178
Throughout the evolutionary history of life, only three vertebrate lineages took to the air by acquiring a body plan suitable for powered flight: birds, bats, and pterosaurs. Because pterosaurs were the earliest vertebrate lineage capable of powered flight and included the largest volant animal in the history of the earth, understanding how they evolved their flight apparatus, the wing, is an important issue in evolutionary biology. Herein, I speculate on the potential basis of pterosaur wing evolution using recent advances in the developmental biology of flying and non‐flying vertebrates. The most significant morphological features of pterosaur wings are: (i) a disproportionately elongated fourth finger, and (ii) a wing membrane called the brachiopatagium, which stretches from the posterior surface of the arm and elongated fourth finger to the anterior surface of the leg. At limb‐forming stages of pterosaur embryos, the zone of polarizing activity (ZPA) cells, from which the fourth finger eventually differentiates, could up‐regulate, restrict, and prolong expression of 5′‐located Homeobox D (Hoxd) genes (e.g. Hoxd11, Hoxd12, and Hoxd13) around the ZPA through pterosaur‐specific exploitation of sonic hedgehog (SHH) signalling. 5′Hoxd genes could then influence downstream bone morphogenetic protein (BMP) signalling to facilitate chondrocyte proliferation in long bones. Potential expression of Fgf10 and Tbx3 in the primordium of the brachiopatagium formed posterior to the forelimb bud might also facilitate elongation of the phalanges of the fourth finger. To establish the flight‐adapted musculoskeletal morphology shared by all volant vertebrates, pterosaurs probably underwent regulatory changes in the expression of genes controlling forelimb and pectoral girdle musculoskeletal development (e.g. Tbx5), as well as certain changes in the mode of cell–cell interactions between muscular and connective tissues in the early phase of their evolution. Developmental data now accumulating for extant vertebrate taxa could be helpful in understanding the cellular and molecular mechanisms of body‐plan evolution in extinct vertebrates as well as extant vertebrates with unique morphology whose embryonic materials are hard to obtain. 相似文献