166 research outputs found
The Significance of Splenectomy for Advanced Proximal Gastric Cancer
Objectives. The significance of splenectomy in advanced proximal gastric cancer is examined retrospectively. Methods. From 1994 to 2004, 505 patients with advanced proximal gastric cancer underwent curative total gastrectomy with preserving spleen (T) for 264 patients and total gastrectomy with splenectomy (ST) for 241 patients. Results. Patients who underwent splenectomy showed more advanced lesions. The metastatic rate of lymph node (LN) in the splenic hilus (No. 10) in ST was 18.3%. As for the incidence of surgical complications, there was not statistically difference except for pancreatic fistula. The index of estimated benefit of (No. 10) LN was 4.2, which was similar to that of (No. 9), (No. 11p), (No. 11d), and (No. 16) LNs. 5-year survival rate of (No. 10) positive group was 22.2%. 5-year survival rates of pSE and pN2 in T group were better than that of pSE and pN2 in ST, respectively. The superiority of ST was not confirmed even in Stage II, IIIA, and IIIB. Conclusion. Splenectomy was not effective for patients with (No. 10) metastasis in long-term survival. Spleen-preserving total gastrectomy will be feasible and be enough to accomplish radical surgery for locally advanced proximal gastric cancer
Spontaneous Plasticity of Multineuronal Activity Patterns in Activated Hippocampal Networks
Using functional multineuron imaging with single-cell resolution, we examined how hippocampal networks by themselves change the spatiotemporal patterns of spontaneous activity during the course of emitting spontaneous activity. When extracellular ionic concentrations were changed to those that mimicked in vivo conditions, spontaneous activity was increased in active cell number and activity frequency. When ionic compositions were restored to the control conditions, the activity level returned to baseline, but the weighted spatial dispersion of active cells, as assessed by entropy-based metrics, did not. Thus, the networks can modify themselves by altering the internal structure of their correlated activity, even though they as a whole maintained the same level of activity in space and time
Design and Development of a Legged Robot Research Platform JROB-1
Proceedings of the 1998 IEEE International Conference on Robotics & Automation, Leuven, Belgium, May 199
Bilateral Adrenocortical Adenomas Causing Cushing\u27s Syndrome : Report of A Case Successfully Treated by Adrenal-Sparing Surgery
Cloud processing of mineral dust: direct comparison of cloud residual and clear sky particles during AMMA aircraft campaign in summer 2006
金沢大学フロンティアサイエンス機構In order to gain insights into the characteristics of the mineral dust particles incorporated in the actual cloud droplets and the related cloud processing, the French ATR-42 research aircraft equipped both with a counterflow virtual impactor (CVI) and community aerosol inlet was deployed in Niamey, Niger (13°30\u27 N, 02°05\u27 E) in August 2006 within the framework of the African Monsoon Multidisciplinary Analysis (AMMA) project. Cloud residual and clear-sky particles were collected separately and analyzed individually using a transmission electron microscope (TEM) and a scanning electron microscope coupled with an energy dispersive X-ray spectroscopy (SEM-EDX). The analysis revealed interesting characteristics on the coarse dust particles (Dp>1μm), particularly those which likely had acted as CCN. Traces of heterogeneously formed secondary sulfate, chloride and nitrate were found on many dust particles (though fraction of sulfate may be present in the form of gypsum as primary dust component). These secondary species were particularly enhanced in clouds (i.e. cloud processing). The study illustrates that calcium-rich particles assumed to be carbonates (Calcite, Dolomite) contained the secondary species in significantly larger frequency and amount than the silicates (Quartz, Feldspar, Mica, Clay), suggesting that they represent the most reactive fraction of the mineral dust. A surprisingly large fraction of the Ca-rich particles were already found in deliquesced form even in clear-sky conditions, most probably reflecting their extreme hygroscopicity, resulting from their reaction with HNO3 gas. Both silicate and Ca-rich particles were found dominant among the supermicron cloud residues, and they were supposed to be those previously activated as CCN. It is highly probable that the observed formation of soluble materials enhanced their cloud nucleating abilities
Assessment of composition and origin of airborne bacteria in the free troposphere over Japan
Long-range transport of airborne microorganisms through the free troposphere significantly impacts biological ecosystems, human life, and atmospheric processes in downwind areas. However, microbial communities in the free troposphere have rarely been investigated because the direct collection of microbial cells at high altitudes requires sophisticated sampling techniques. In this study, tropospheric air sampling was performed using a balloon and an aircraft at 800 m and 3000 m, respectively, over the Noto Peninsula in Japan (37.5°N, 137.4°E) where free tropospheric winds carry aerosols from continental areas. The air samples were collected during four different sampling periods when air masses came from desert regions of Asian continent (west samples) and from Siberia of Russia North Asia (north samples). The west samples contained higher levels of aerosols, and bacteria from the west samples grew in culture media containing up to 15% NaCl. In contrast, bacteria from the north samples could not be cultured in the same media. All isolates obtained from the NaCl-amended cultures were similar to Bacillus subtilis and classified as Firmicutes. A 16S rDNA clone library prepared from the west samples was mainly composed of one phylotype of Firmicutes that corresponded to the cultured B. subtilis sequence. A clone library prepared from the north samples consisted primarily of two phyla, i.e., Actinobacteria and Proteobacteria, which are known to dominantly inhabit low-temperature environments of North Asia. Our results suggest that airborne bacterial communities at high altitudes include several species that vary by the direction and interaction of free tropospheric winds. •Aerosol samples were collected at high altitudes using an aircraft and a balloon.•During four sampling periods, the air masses came from the Gobi Desert and North Asia.•Airborne bacterial species were investigated using a 16S rDNA clone library technique.•Bacterial species at high altitudes varied by the direction of free tropospheric winds. © 2013 Elsevier Ltd
Active Hippocampal Networks Undergo Spontaneous Synaptic Modification
The brain is self-writable; as the brain voluntarily adapts itself to a changing environment, the neural circuitry rearranges its functional connectivity by referring to its own activity. How the internal activity modifies synaptic weights is largely unknown, however. Here we report that spontaneous activity causes complex reorganization of synaptic connectivity without any external (or artificial) stimuli. Under physiologically relevant ionic conditions, CA3 pyramidal cells in hippocampal slices displayed spontaneous spikes with bistable slow oscillations of membrane potential, alternating between the so-called UP and DOWN states. The generation of slow oscillations did not require fast synaptic transmission, but their patterns were coordinated by local circuit activity. In the course of generating spontaneous activity, individual neurons acquired bidirectional long-lasting synaptic modification. The spontaneous synaptic plasticity depended on a rise in intracellular calcium concentrations of postsynaptic cells, but not on NMDA receptor activity. The direction and amount of the plasticity varied depending on slow oscillation patterns and synapse locations, and thus, they were diverse in a network. Once this global synaptic refinement occurred, the same neurons now displayed different patterns of spontaneous activity, which in turn exhibited different levels of synaptic plasticity. Thus, active networks continuously update their internal states through ongoing synaptic plasticity. With computational simulations, we suggest that with this slow oscillation-induced plasticity, a recurrent network converges on a more specific state, compared to that with spike timing-dependent plasticity alone
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