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S. Miyazaki H. Shimoji R. Suzuki I. Chinushi H. Takayanagi H. Yaguchi T. Miura K. Maekawa 《Insect molecular biology》2021,30(1):113-121
In eusocial insect colonies, non-reproductive workers often perform different tasks. Tasks of an individual worker are shifted depending on various factors, e.g., age and colony demography. Although a vitellogenin (Vg) gene play regulatory roles in both reproductive and non-reproductive division of labours in a honeybee, it has been shown that the insect Vg underwent multiple gene duplications and sub-functionalisation, especially in apical ant lineages. The regulatory roles of duplicated Vgs were suggested to change evolutionarily among ants, whereas such roles in phylogenetically basal ants remain unclear. Here, we examined the expression patterns of conventional Vg (CVg), Vg-like A, Vg-like B and Vg-like C, as well as Vg receptor, during the task shift in an age-dependent manner and under experimental manipulation of colony demography in a primitive ant Diacamma sp. Expressions of CVg and Vg-like A in a brain were associated with a nursing task. It is suggested that associations of brain expressions of these Vgs with worker tasks were acquired in the basal ant lineage, and that such Vg functions could have sub-functionalised in the derived ant lineage. 相似文献
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Duncan J Wood Takanobu Shiraishi Nobuya Shinozaki Richard van Noort 《Dental materials》2008,24(12):1661-1669
OBJECTIVE: The study was conducted to observe the spectral reflectance curves, and evaluate the color coordinates (CIELAB) of VM7 dentin ceramics (VITA, Germany) across the whole 3D-MASTER shade system. METHODS: Three disc samples, 13 mm in diameter and 1.4mm in thickness, were produced for each shade by firing following the manufacturer's instructions. Each fired disc was ground to a thickness of 1.0 mm and both faces were polished. Spectral reflectance data in the visible spectrum under the standard illuminant D65 were collected at 1 nm intervals by using a computer-controlled spectrophotometer. Color coordinates, L*, a*, b*, C*, h, in the three-dimensional CIELAB color space were obtained. RESULTS: (1) Spectral reflectance in the short-wavelength range systematically decreased with increasing chroma number (M1, M2, and M3) when compared within the same value (lightness) group (1M, 2M, 3M, 4M, and 5M). (2) Spectral reflectance decreased systematically across the whole visible spectrum with increasing value group when compared within the same chroma group. (3) A negative relationship was recognized between lightness (L*) and chromaticity index a* (red-green direction). That is, a* coordinate increases from approximately 1 for the 1M1 sample to approximately 13 for the 5M3 sample, the corresponding lightness systematically decreased from 87 to 69. (4) With increasing a* coordinate, hue angle (h) significantly decreased from 85 degrees for the 1M1 sample to 69 degrees for the 5M3 sample. (5) Lightness apparently increased with increasing hue angle (h) throughout the whole range of the 3D-MASTER shade system. (6) A strong positive relationship between chroma (C*) and chromaticity index b* (yellow-blue direction) was found, demonstrating that the chroma of the present ceramic is mainly controlled by the b* coordinate. SIGNIFICANCE: Systematic variations in spectral reflectance and color coordinates of VM7 dentin were observed throughout the 3D-MASTER shade system and were suggested to be caused by the fine structure of the sample which can interfere with shorter wavelengths in the visible spectrum. 相似文献
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Naoshi Kubo Masaichi Ohira Katsunobu Sakurai Takahiro Toyokawa Hiroaki Tanaka Kazuya Muguruma Hisashi Nagahara Kenjiro Kimura Eiji Noda Ryosuke Amano Nobuya Yamada Masakazu Yashiro Kiyoshi Maeda Tetsuji Sawada Kosei Hirakawa 《World journal of surgery》2013,37(7):1681-1687
Background
We retrospectively investigated prognostic factors to be used in selecting the patients with stage IV gastric cancer (GC) who have an unfavorable prognosis after palliative gastrectomy.Methods
A total of 146 GC patients at stage IV who had undergone palliative gastrectomy were enrolled. Various clinicopathological parameters were evaluated for prognosis.Results
Surgical morbidity and hospital mortality occurred in 35 (23.9 %) and 4 (2.7 %) patients, respectively. The overall 5-year survival rate and the median survival time were 11.2 % and 13.2 months, respectively. Of the 146 patients, 64 had uncomfortable symptoms associated with GC and 76 had no such symptoms. Of the 64 patients with uncomfortable symptoms, 60 (93.7 %) experienced relief of these symptoms after palliative surgery. Multivariate analysis for patients without uncomfortable symptoms associated with GC revealed that the number of incurable factors and serum SPan-1 level were independent prognostic factors.Conclusions
Patients with stage IV GC who had multiple incurable factors and a high level of serum SPan-1 might not be candidates for palliative gastrectomy for the purpose of prognostic benefit. 相似文献7.
Sayuki Kobayashi Terumi Hayashi Kaori Akiya Michiko Ichihara Michiko Minai Yoshihiko Sakai Kan Takayanagi 《Journal of Medical Ultrasonics》2006,33(1):23-28
Purpose We aimed to identify the electrical stimulation sites of pacemaker leads using a tissue tracking method of tissue Doppler
imaging.
Methods The study group consisted of 30 patients who had undergone permanent pacemaker implantation. During tissue Doppler imaging,
the initial contraction site was seen as a red area stimulated by the pacemaker lead. This red area was analyzed precisely
using time–distance curves generated by tissue tracking.
Results The initial contraction site of the myocardium was located in the interventricular septum in seven patients and in the apical
portion of the right ventricle in 11 patients. Furthermore, analysis of time–distance curves demonstrated that one point within
the red area started to move earlier than the others.
Conclusion The site of electrical stimulation within the myocardium can be determined from the time–distance curves generated by the
tissue tracking method.
A summary of this paper was presented at the 77th Conference of the Japan Society of Ultrasonics in Medicine (Tochigi, April
2004) 相似文献
8.
Yoshikawa M Suzumura A Ito A Tamaru T Takayanagi T 《The Tohoku journal of experimental medicine》2002,196(3):167-177
Nitric oxide (NO) is considered to play a crucial role in the development of various pathological processes in the CNS, such as neuronal degeneration, inflammation and demyelination. In order to search for the agents which suppress NO production in the CNS, we examined the effects of one of the agents which elevate cyclic AMP production, phosphodiesterase inhibitors (PDEIs), on NO production by glial cells in vitro. All the types of PDEIs, from type I- to V-specific and non-specific, suppressed the production of NO by mouse microglia and astrocytes stimulated with lipopolysaccharide, in a dose-dependent manner. Suppression of inducible NO synthase by PDEIs was confirmed by the expression of mRNA by RT-PCR. Although it required 10 microM or higher concentration to effectively suppress NO production in vitro, certain combinations of three different PDEIs synergistically suppressed NO production by astrocytes at 1 microM which could be obtained in vivo at usual therapeutic doses. Similary, combinations of three PDEIs at 1 microM synergistically increased intracellular cAMP in astrocytes. The suppressive effects of PDEIs on NO production were abolished by addition of tumor necrosis factor alpha (TNFalpha). Thus, the main suppression mechanism of NO might be indirect through suppression of TNFalpha. Since some PDEIs are reported to pass through the blood-brain-barrier, the combination of three PDEIs may be worth trying in neurological diseases, such as multiple sclerosis, human immunodeficiency virus-related neurological diseases and other neurodegenerative disorders in which NO may play a crucial role. 相似文献
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Yuka Takayanagi Satoshi Yuda Hideaki Sugio Maki Ichimura Hitomi Masuda-Yamamoto Norie Tanaka-Saito Tetsuji Miura 《Journal of Echocardiography》2012,10(3):101-103
We present a case of a rare combination of ventricular septal defect and atrial septal aneurysm (ASA) with a patent foramen ovale (PFO) in a 57-year-old female. She was referred to our hospital for the treatment of irregular palpitation and exertional shortness of breath. Two-dimensional transesophageal echocardiography (2D-TEE) with color Doppler imaging demonstrated an ASA with two lines of shunt flows. Three-dimensional transesophageal echocardiography (3D-TEE) could clearly visualize the morphology of the PFO in the surgeon??s view and demonstrated a crescent-shaped opening of the PFO. 3D-TEE appears to be a more accurate modality than 2D-TEE for the assessment of PFO. 相似文献