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991.
Yoshihiro Matsutnoto Ikuo Saiki Takashi Makabe Junya Yoneda Jun Murata Fusao Kimizuka Yukuo Ishizaki Ikunoshin Kato Ichiro Azuma 《Cancer science》1991,82(10):1130-1138
We investigated the inhibitory mechanism of liver metastasis by using recombinant fragments with cell- and/or heparin-binding domains (C-274, H-271 or the fusion fragment CH-271). Intravenous co-injection of L5178Y-ML25 cells with CH-271 was more effective for the inhibition of liver metastasis than C-274, H-271 or C-274+H-271. Reduction of the arrest and retention of the radiolabeled tumor cells in the liver of mice was found when CH-271 was co-injected with tumor cells. L5178Y-ML25 cells adhered both concentration- and time-dependently to the substrates precoated with fibronetin, laminin and reconstituted basement membrane, Matrigel. The tumor cell adhesions to the substrates were inhibited in the presence of CH-271. The tumor cell interaction with CH-271-substrate was inhibited by heparin, and monoclonal antibodies (IST-1 or IST-2) against the heparin-binding domain of fibronectin. However, monoclonal antibodies against the cell-binding domain failed to block the interaction. Similarly, CH-271-mediated antimetastatic activity was also inhibited by the treatment of CH-271 with IST-1 before the co-injection with tumor cells, whereas monoclonal antibody against the cell-binding domain had no effect. Thus, the antimetastatic effect of CH-271 fusion fragment on liver metastasis of L5178Y-ML25 cells may be partly due to interference with the adhesive interaction of tumor cells with extracellular matrix or basement membrane components by a heparin-binding domain-dependent mechanism. 相似文献
992.
993.
Toshiya Ohtsuka Noboru Motomura Yoshihiro Suematsu Shinichi Takamoto 《European journal of cardio-thoracic surgery》2002,22(3):443-444
This communication describes the surgical technique and clinical outcomes of a simple coronary perfusion technique for use during off-pump coronary artery bypass grafting. An intra-coronary shunt tube connected to the graft conduit (saphenous vein or radial artery) with an arterial blood source (ascending aorta or right internal thoracic artery) was inserted distally via a coronary arteriotomy for temporary perfusion of six left anterior descending arteries and two right coronary arteries. 相似文献
994.
Masako Abe Naoto Ito Shigeki Morikawa Masaki Takasu Tetsuma Murase Takanori Kawashima Yoshihiro Kawai Junko Kohara Makoto Sugiyama 《Virus research》2009,144(1-2):250-257
A total of 171 fecal specimens collected from healthy calves on a beef farm in Gifu Prefecture, Japan in 2006–2007 were examined for group A rotaviruses by RT-semi-nested PCR targeting the coding region for VP8*. Nine specimens were positive for rotavirus. G and P genotyping indicated that one strain was G10P[11]-like and six strains were considered to be the same unknown G and P genotypes. Among these six untypeable strains, one strain, AzuK-1, was adapted to cell culture and analyzed. Sequence and phylogenetic analyses of the full lengths of VP4 and VP7 genes revealed that AzuK-1 strain is a novel bovine rotavirus bearing new G21 and P[29] genotypes as confirmed by the RCWG. Furthermore, we detected G21P[29] rotaviruses in fecal specimens collected from healthy calves in Hokkaido, Japan during the period from 1997 to 1998. These findings suggest that novel G21P[29] rotaviruses have been widely prevalent among cattle for over 10 years in Japan. 相似文献
995.
Taro Fujikawa MD Yoshihiro Noguchi MD Taku Ito MD Masatoki Takahashi MD Ken Kitamura MD 《The Laryngoscope》2010,120(1):166-171
Objectives/Hypothesis:
To describe the audiological profiles in a Japanese family with autosomal dominant hereditary sensorineural hearing loss (SNHL) and to identify the causative gene.Study Design:
A family study at an academic tertiary referral center.Methods:
A family with autosomal dominant hereditary SNHL was enrolled. Hearing loss (HL) of affected members showed mid‐frequency SNHL in childhood and progressed at lower frequencies with age, resulting in low‐frequency SNHL. To understand the pathology of HL of this family, we performed a genetic analysis of WFS1, TECTA, and GJB2 by direct sequencing, and further audiovestibular examinations, including speech audiometry, distortion product otoacoustic emissions, electrocochleography, auditory brainstem responses, and electronystagmography for some affected members.Results:
A heterozygous A‐to‐C nucleotide transversion (c.2507A>C), resulting in a lysine‐to‐threonine substitution at codon 836 (K836T) was identified in exon 8 of WFS1. K836T was segregated with HL in the 15 participants in the genetic study but was not detected in the 212 normal chromosomes. Only polymorphic changes were detected in TECTA and GJB2. Audiovestibular examinations indicated purely cochlear HL and normal vestibular function. The summating potential/action potential ratios in electrocochleography increased in the bilateral ears of the proband.Conclusions:
The family described with autosomal dominant inheritance of K836T of the WFS1 gene demonstrates a progressive hearing loss in the lower frequencies. Laryngoscope, 2010 相似文献996.
We have recently reported that the burst firing neurons are found in layer III as well as in layer V of cat sensorimotor cortex in vitro. In the present study, we examined the synaptic excitability of layer III neurons by white matter stimulation and compared with their firing patterns against the current injections through the recording microelectrodes. The firing patterns of layer III neurons were classified into three main classes as in our previous study, i.e., (1) regular spiking (RS), i.e., the tonic firing that often exhibited spike-frequency adaptation, (2) burst-and-single spiking (BS), i.e., the initial bursting followed by tonic firing, (3) repetitive-bursting (RB), the burst firing that recurred at fast frequency. In RS cells, single action potential was superimposed on the largest EPSPs among all cell types analyzed. BS cells also fired single action potential and never exhibited burst firing synaptically. Only in a part of RB cells, synaptic bursting instead of single action potential was evoked on smaller EPSPs. IPSPs could be observed in about 60% of all the recorded RS and BS cells, however, they were observed in only 10% of the RB cells. 相似文献
997.
Mamiko Nagashima Ichirou Ohki Yasuyuki Nagasato Masatomo Mori Masahiko Murakami Yoshihiro Fukoue Ugen Lee 《Digestive endoscopy》2001,13(1):41-44
Lipoma of the esophagus is rare. There are few reports of the endoscopic resection of esophageal lipoma. We present a 73‐year‐old woman with lipoma of the esophagus which was successfully extirpated using the technique of endoscopic mucosal resection. To determine the depth of tumor invasion, endoscopic ultrasonography was used. A total of 31 cases of esophageal lipoma have been reported in Japan. Of these, seven were successfully resected using endoscopic techniques. Lipomas of the esophagus can grow to become large pedunculated tumors which can obstruct the airway. The majority of these tumors occur in the cervical portion of the esophagus. Most patients have no symptoms. These tumors can be resected using minimally invasive surgery when they are small. 相似文献
998.
Michiko Tojo Tetsuji Mori Hidenori Kiyosawa Yutaka Honma Yoshihiro Tanno Ken-ya Kanazawa Sachihiko Yokoya Fumio Kaneko Akio Wanaka 《Pathology international》1999,49(8):687-694
In basal cell nevus syndrome (BCNS) patients, mutations of a gene, patched (ptc), which encodes a putative signal transducer of sonic hedgehog protein (SHH), were found and are thought to be one of the major causes of BCNS. The SHH signaling pathway is an important developmental pathway, and ptc protein (PTC) is a suppressive component serving as a receptor for the secreted SHH. Another transmembrane protein, smoothened (SMO), forms a complex with PTC and regulates this signaling pathway. Recent transgenic studies have strengthened the importance of the SHH signaling system in the etiology of basal cell carcinoma (BCC). In this study, we examined the expression patterns of mRNA for ptc and smo in two different BCC subtypes and normal skin. We found that the expressions of ptc and smo mRNA were enhanced in the tumor nests of the nodular BCC, especially at the advancing portions, but were under the detectable level in the superficial BCC cases examined, indicating that ptc and smo mRNA expressions might be associated with BCC tumor progression and divide the BCC histologic types into two subtypes, superficial and nodular types. In addition, no obvious signals for ptc and smo mRNA were detected in the normal human epidermis, appendages, or seborrheic keratosis, indicating that the abnormal proliferation of follicular epithelial cells caused by ptc, smo and/or other genetic changes, which also cause ptc and smo overexpressions, might result in BCC tumor formation. 相似文献
999.
Relaxation-compensated fast multislice amide proton transfer (APT) imaging of acute ischemic stroke.
Phillip Zhe Sun Yoshihiro Murata Jie Lu Xiaoying Wang Eng H Lo A Gregory Sorensen 《Magnetic resonance in medicine》2008,59(5):1175-1182
Amide proton transfer (APT) imaging is a variant form of chemical exchange saturation transfer (CEST) imaging that is based on the magnetization exchange between bulk water and labile endogenous amide protons. Given that chemical exchange is pH-dependent, APT imaging has been shown capable of imaging ischemic tissue acidosis, and as such, may serve as a surrogate metabolic imaging marker complementary to perfusion and diffusion MRI. In order for APT imaging to properly diagnose heterogeneous pathologies such as stroke and cancer, fast volumetric APT imaging has to be developed. In this study the evolution of CEST contrast after RF irradiation was solved showing that although the CEST steady state is reached by the apparent longitudinal relaxation rate, the decreases of CEST contrast after irradiation is governed by the intrinsic relaxation constant. A volumetric APT imaging sequence is proposed that acquires multislice images immediately after a single long continuous wave (CW) RF irradiation, wherein the relaxation-induced loss of CEST contrast is compensated for during postprocessing. The proposed technique was verified by numerical simulation, a tissue-like dual-pH phantom, and demonstrated on an embolic stroke animal model. In summary, our study has established a fast volumetric pH-weighted APT imaging technique, allowing further investigation to fully evaluate its diagnostic power. 相似文献