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991.
K Kato K Onodera M Sawa M Imai T Kawahara S Kasai M Mito 《Canadian Metallurgical Quarterly》1996,222(1):101-106
Expression of genes encoding insulin-like growth factor I (IGF-I), insulin-like growth factor II (IGF-II) and type I insulin-like growth factor receptor (IGFr) was measured in theca and granulosa cells from the ovary of the laying hen, using an RNase protection assay. Expression of genes encoding IGF-I and -II was confined to theca tissue and expression was not detected in granulosa cells. In contrast, expression of genes encoding IGFr in granulosa cells was significantly greater than that in theca tissue. The 98 base IGF-II probe was similar to a region of the second coding exon of chicken IGF-II and produced multiple RNase-protected RNA hybrids. Theca RNA from follicles at all stages of development produced RNase-protected hybrids of size 98, 96 and 90 bases; however, an additional band (66 bases) was also observed in theca RNA from small yellow follicles. The stage of follicular development during which maximum amounts of the 66 base RNase-protected fragment was detected correlates with the stage at which small follicles are selected for recruitment into the follicular hierarchy. The results provide evidence for the involvement of IGFs in the intraovarian control of ovarian function in a non-mammalian species, and highlight the importance of IGF-II in this process. 相似文献
992.
T Hiramatsu Y Takanashi Y Imai S Hoshino K Seo M Terada Y Iwata H Tomimatsu 《Canadian Metallurgical Quarterly》1998,65(4):1110-1114
BACKGROUND: In the repair of anomalous connection of the pulmonary veins to the right atrium, the use of a baffle of pericardium to divert the pulmonary venous blood into the left atrium could cause pulmonary venous obstruction as a result of thickening of the pericardial patch. Anomalous pulmonary venous drainage to the right atrium caused by malposition of the atrial septum primum can be repaired by displacing the shifted septum primum to the normal position. METHODS: In 5 patients with total (n=2) or partial (n=3) anomalous pulmonary venous drainage into the right atrium, the septum primum was shifted toward the left atrium and the pulmonary veins drained into the anatomic right atrium despite their normal connection with the posterior wall of the left atrium. This method consisted of incision of the posterior edge of the atrial septum primum and displacement of the incised atrial septum between the anomalous pulmonary veins and both venae cavae. No patch was used. RESULTS: Postoperative echocardiography showed a wide pathway from the pulmonary veins to the left atrium with no stenotic portions. No atrial arrhythmias occurred after the operation. CONCLUSIONS: This technique may be advantageous because it allows for future growth of the route of the pulmonary venous pathway and avoids postoperative supraventricular arrhythmias. 相似文献
993.
H Imai Y Horiguchi H Kubo T Suzuki K Sakamoto M Uematsu F Takeuchi H Nakamura T Hayashi A Tokuda M Asano J Murai K Osakabe Y Kushi T Nishikawa Y Sugita C Soeshima 《Canadian Metallurgical Quarterly》1998,56(4):1018-1023
In this report, we showed the efficacy of a new contrast agent (SH/TA-508, Schering AG, Germany) for color Doppler imaging of the pancreatic tumors. In pancreatic ductal cancer, no enhancement of the lesion was observed, but vascular invasion by cancer became to be easily evaluated. On the other hand, hypervascular tumors such as islet cell tumor and cystadenocarcinoma, were increased in color Doppler signals of vessels by SH/TA-508. We concluded that SH/TA-508 was useful for evaluating the vascular invasion by pancreatic cancer as well as vascularity of hypervascular mass and solid component of cystic neoplasma. 相似文献
994.
We performed morphological studies of skin and measured glycosaminoglycans in the urine from patients with sporadic amyotrophic lateral sclerosis (ALS) and control subjects. The wide spaces separating collagen bundles reacted strongly with alcian blue stain in ALS patients and stained more markedly as ALS progressed. Staining with alcian blue was virtually eliminated by Streptomyces hyaluronidase. The urinary excretion of hyaluronic acid (HA) (mg/day) was significantly increased (P < 0.01) in ALS patients compared with that of control subjects, and there was a significant positive correlation between the excreted amount of HA and the duration of illness in advanced ALS patients with a duration of more than 2 years from clinical onset (r = 0.72, P < 0.02). We suggest that sporadic ALS includes a metabolic disorder of HA in which an accumulation of HA in the skin is linked to an increased urinary excretion of HA. 相似文献
995.
Hiroyuki Sasakura Yoshiya Akagi Masashi Tanaka Shigeki Tsukui Motoaki Adachi 《Journal of Materials Science: Materials in Electronics》2014,25(5):2183-2187
We have discovered new members of the Pb-based 1222 layered cuprates containing sulfur of (Pb0.75S0.25)Sr2(RE1.6Ce0.4)Cu2O z with RE = Sm, Gd, Dy, and Ho. All the samples are of almost-single 1222 phase. From the ρ–T and χ–T measurements, they are found to be superconductors after annealing under 125 atm O2 atmosphere at 400 °C. Among them, the sample with RE = Gd is found to show superconductivity at the highest temperature of 30 K. 相似文献
996.
Kani J. Iwatsuki K. Imai T. 《IEEE journal of selected topics in quantum electronics》2006,12(4):661-668
This paper describes optical multiplexing technologies expected to be applied to access-area networks. First, these technologies are broadly categorized into wavelength-division multiplexing (WDM) and optical code-division multiple access (OCDMA), and possible variants are described in a comparison to time-division multiple access (TDMA). Next, their typical performances reported so far are overviewed in relation to the light sources utilized. While it is well known that WDM/OCDMA exhibits higher performance with laser sources, it is pointed that WDM/OCDMA with incoherent light sources are interesting alternatives for access-area applications. Two multiplexing methods that use incoherent light sources are introduced in more detail; one is spectrum-sliced WDM and the other is coherence-multiplexed CDMA. After the introduction of transmission experiments, their performance limitations are discussed. 相似文献
997.
The preparation of dispersants with carboxyl groups from acid lignin (a byproduct in the saccharification process of woody materials that are renewable resources) was investigated, and their dispersion efficiency was evaluated. In this study, sulfuric acid lignin (SAL) was selected as a representative acid lignin. To convert SAL to water‐soluble polymers, it was first subjected to phenolation with sulfuric acid to enhance its chemical reactivity. The introduction of a carboxy group was carried out with two methods. One was carboxymethylation with bromoacetic acid, and the other was the Mannich reaction with glycine, sarcosine, and iminodiacetic acid. The carboxymethylation product [carboxymethylated phenolized sulfuric acid lignin (CP‐SAL)] with 1.4 carboxymethyl groups per phenolated phenylpropane lignin base unit was soluble in water. The Mannich reaction products were also soluble in water with a lower addition of carboxyl groups than that for CP‐SAL. Surprisingly, all the prepared water‐soluble polymers possessed a higher dispersibility for gypsum paste than commercial lignosulfate. This may be due to the higher molecular weights of acid lignin derivatives. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2508–2513, 2005 相似文献
998.
This paper presents electroencephalogram‐based control of a mobile robot. The purpose of control is to achieve direction control of a mobile robot only by electroencephalogram. We develop an algorithm for directing direction thinking (“going left” or “going right”) and apply it to direction control of a mobile robot. The algorithm is based on time–frequency domain analysis using continuous wavelet transformation. Our experimental results demonstrate the possibility of achieving direction control of a mobile robot only by electroencephalogram. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 39–46, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20109 相似文献
999.
We report a novel hierarchically organized superstructure emerging from an exquisite association of inorganic crystals, organic polymers, and dyes. The resultant K2SO4/poly(acrylic acid) composite includes five different tiers from the nanoscopic to the macroscopic. An additional new tier leading to functionality is formed by the incorporation of organic dyes that are organized in a nanospace. The emergent superstructure and properties are designed through changes in polymer concentration. The multiple roles of the polymer realize the generation of the architecture at each size scale. This model approach should be widely applicable to other systems, allowing for the preparation of innovative materials by an appropriate combination of crystals, polymers, and functional molecules. 相似文献
1000.
The role of floral scents in host location by flower-dwelling thrips and a thrips parasitoid was investigated by experiment in the field. The scent of methyl anthranilate significantly increased the catches of Thrips hawaiiensis, Thrips coloratus, and Ceranisus menes, but had no effect on Thrips tabaci. Anisaldehyde increased the catches of T. hawaiiensis and T. tabaci, but had no such effect on T. coloratus and C. menes. Geraniol increased the catches of T. hawaiiensis, but not of T. coloratus, T. tabaci, or C. menes. Seasonal fluctuations of T. hawaiiensis, T. coloratus, and C. menes can be recorded by using methyl anthranilate as a lure for monitoring. 相似文献