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71.
72.
T. Hashizume H. SaitoT. Sawada T. YaegashiA. Ahmed Ezzat K. SawaiT. Yamashita 《Animal reproduction science》2010
The aims of the present study were to clarify the effect of kisspeptin-10 (Kp10) on the secretion of luteinizing hormone (LH), follicle stimulating hormone (FSH), growth hormone (GH) and prolactin (PRL) in goats, and compare the characteristics of any response with those of the response to gonadotropin-releasing hormone (GnRH). The experiments were performed using four female goats (4–5 years old) in the luteal phase of estrous cycle. A single intravenous (i.v.) injection of 1, 5 and 10 μg/kg b.w. (0.77, 3.85 and 7.69 nmol/kg b.w.) of Kp10 stimulated the release of LH. Maximum values were observed 20–30 min after the injection. On the other hand, Kp10 did not alter plasma GH and PRL concentrations significantly. Three consecutive i.v. injections of Kp10 (5 μg/kg b.w.) or GnRH (5 μg/kg b.w.: 4.23 nmol/kg b.w.) at 2-h intervals increased both plasma LH and FSH levels after each injection (P < 0.05); however, the responses to Kp10 were different from a similar level of GnRH. The rate of decrease in LH and FSH levels following the peak was attenuated in Kp10-treated compared to GnRH-treated animals. These results show that Kp10 can stimulate the release of LH and FSH but not GH and PRL in female goats and suggest that the LH- and FSH-releasing effect of the i.v. injection of Kp10 is less potent than that of GnRH. 相似文献
73.
Extracellular matrix of meningiomas was studied by light and electron microscopy with the aid of immunohistochemical techniques. Special attention was paid to the distribution of type I, III, IV, V collagens and laminin with a comparison between meningothelial and fibroblastic types. Connective tissue fibers and basement membrane were not found among the tumor cells in the meningothelial type, but were found in the fibroblastic type. The immunolocalizations were consistently demonstrated extracellularly, but were not within the cytoplasm. Type I, III and V collagens were usually demonstrated in the fibrous septum in the meningothelial type, while they were localized among the tumor cells in the fibroblastic type. Furthermore, type IV collagen and laminin were demonstrated within the vascular walls or around the syncytium in the meningothelial type, while they were localized among the tumor cells in the fibroblastic type. In both types the expression of type IV collagen and laminin was closely related to the distribution of basement membrane. Although meningothelial and fibroblastic meningiomas showed quite different distribution of extracellular matrices, the profile of collagen types expressed by these two basic types was essentially the same. The cellular derivation of meningiomas was discussed with particular attention to the structure of human arachnoid villi and meninges. 相似文献
74.
75.
Azusa Tanimoto Shinji Takeuchi Hiroshi Kotani Kaname Yamashita Tadaaki Yamada Koushiro Ohtsubo Hiromichi Ebi Hiroko Ikeda Seiji Yano 《BMC pulmonary medicine》2018,18(1):193
Background
Pulmonary carcinosarcoma (PCS) is a rare primary lung malignancy and has a poor prognosis among lung tumor histological subtypes. However, an appropriate treatment strategy has not been developed for unresectable PCS.Case presentation
A 65-year-old man who was diagnosed with PCS was treated by surgical removal of the primary lung lesion, followed by six cycles of adjuvant chemotherapy with cisplatin plus irinotecan. Following the chemotherapy, he experienced a relapse with brain metastasis, which induced the rapid onset of left leg paralysis. Radical surgical resection and stereotactic radiosurgery to the resection cavity were performed. However, meningeal dissemination and new lung metastases occurred after a year and half. To control these multiple metastatic lesions, the patient was treated with the multiple kinase inhibitor pazopanib. No change was observed in the meningeal dissemination, while the metastatic lung lesions were prominently reduced in size following treatment with pazopanib. Consequently, the patient showed a partial response to pazopanib treatment, although the dose of pazopanib was reduced by half as a result of thrombocytopenia.Conclusion
This is the first report of metastatic PCS showing an evident therapeutic response to tumor-targeted therapy. We suggest that pazopanib may be a therapeutic option for patients with metastatic PCS.76.
Serotonin (5-HT)-stimulated intracellular Ca2+ concentration change was studied in the platelets of healthy subjects, using fluorescent Ca indicator fura-2. 5-HT increased the Ca2+ response in a concentration-dependent manner. 10 microM of 5-HT induced the maximal response and its EC50 value was 0.4 microM. This response was potently inhibited by selective 5-HT2 antagonists, suggesting that 5-HT-induced Ca2+ mobilization in human platelets is mediated by 5-HT2 receptors. This 5-HT2-mediated Ca2+ response was not significantly affected by the time of blood sampling, gender, meal or exercise. However, this response declined with time after blood drawing, suggesting that it must be measured as soon as possible after sampling. These results indicate that 5-HT-stimulated Ca2+ response in human platelets is a stable parameter and that it will be suitable for assessing 5-HT2 receptor function in depressed patients. 相似文献
77.
Diane Y Kim Peter D Countway Adriane C Jones Astrid Schnetzer Warren Yamashita Christine Tung David A Caron 《The ISME journal》2014,8(3):515-530
The monthly, seasonal and interannual variability of microbial eukaryote assemblages were
examined at 5 m, the deep chlorophyll maximum, 150 m and 500 m at the
San Pedro Ocean Time-series station (eastern North Pacific). The depths spanned
transitions in temperature, light, nutrients and oxygen, and included a persistently
hypoxic environment at 500 m. Terminal restriction fragment length polymorphism was
used for the analysis of 237 samples that were collected between September 2000 and
December 2010. Spatiotemporal variability patterns of microeukaryote assemblages indicated
the presence of distinct shallow and deep communities at the SPOT station, presumably
reflecting taxa that were specifically adapted for the conditions in those environments.
Community similarity values between assemblages collected 1 month apart at each depth
ranged between ∼20% and ∼84% (averages were
∼50–59%). The assemblage at 5 m was temporally more dynamic than
deeper assemblages and also displayed substantial interannual variability during the first
∼3 years of the study. Evidence of seasonality was detected for the microbial
eukaryote assemblage at 5 m between January 2008 and December 2010 and at
150 m between September 2000 and December 2003. Seasonality was not detected for
assemblages at the deep chlorophyll a maximum, which varied in depth seasonally,
or at 500 m. Microbial eukaryote assemblages exhibited cyclical patterns in at
least 1 year at each depth, implying an annual resetting of communities. Substantial
interannual variability was detected for assemblages at all depths and represented the
largest source of temporal variability in this temperate coastal ecosystem. 相似文献
78.
Akira Nakatsuma Mugiho Kaneda Hiromi Kodama Mika Morikawa Satoshi Watabe Kazunari Nakaishi Masakane Yamashita Teruki Yoshimura Toshiaki Miura Masaki Ninomiya Etsuro Ito 《PloS one》2015,10(6)
To reduce the window period between HIV-1 infection and the ability to diagnose it, a fourth-generation immunoassay including the detection of HIV-1 p24 antigen has been developed. However, because the commercially available systems for this assay use special, high-cost instruments to measure, for example, chemiluminescence, it is performed only by diagnostics companies and hub hospitals. To overcome this limitation, we applied an ultrasensitive ELISA coupled with a thio-NAD cycling, which is based on a usual enzyme immunoassay without special instruments, to detect HIV-1 p24. The p24 detection limit by our ultrasensitive ELISA was 0.0065 IU/assay (i.e., ca. 10-18 moles/assay). Because HIV-1 p24 antigen is thought to be present in the virion in much greater numbers than viral RNA copies, the value of 10-18 moles of the p24/assay corresponds to ca. 103 copies of the HIV-1 RNA/assay. That is, our ultrasensitive ELISA is chasing the detection limit (102 copies/assay) obtained by PCR-based nucleic acid testing (NAT) with a margin of only one different order. Further, the detection limit by our ultrasensitive ELISA is less than that mandated for a CE-marked HIV antigen/antibody assay. An additional recovery test using blood supported the reliability of our ultrasensitive ELISA. 相似文献
79.
Removal of the ganglion or severance of the nerve cords at the thorax in mature larvae of the swallowtail, Papilio xuthus, induced systemic distension of the body by swallowing excess air. Such a distension, however, was never induced by simultaneous extirpation of the brain, suboesophageal ganglion, or frontal ganglion, or by severance of the recurrent nerve. Removal of an abdominal ganglion induced distension of the posterior part of the body accompanied by shrinkage of the anterior part. The latter phenomenon appears to be induced by a different mechanism from that of systemic distension. 相似文献
80.
Complete Nucleotide Sequence and Genetic Organization of Aichi Virus, a Distinct Member of the Picornaviridae Associated with Acute Gastroenteritis in Humans 总被引:8,自引:0,他引:8 下载免费PDF全文
Teruo Yamashita Kenji Sakae Hideaki Tsuzuki Yasumoto Suzuki Naohisa Ishikawa Naokazu Takeda Tatsuo Miyamura Shudo Yamazaki 《Journal of virology》1998,72(10):8408-8412
The complete nucleotide sequence of a novel enteric virus, Aichi virus, associated with nonbacterial acute gastroenteritis in humans was determined. The Aichi virus genome proved to be a single-stranded positive-sense RNA molecule with 8,251 bases excluding a poly(A) tail; it contains a large open reading frame with 7,302 nucleotides that encodes a potential polyprotein precursor of 2,433 amino acids. The genome contains a 5′ nontranslated region (NTR) with 712 bases and a 3′ NTR with 240 bases followed by a poly(A) tail. The structure of the genome, VPg–5′ NTR–leader protein–structural proteins–nonstructural proteins–3′ NTR–poly(A), was found to be typical of a picornavirus. The VP0-VP3 and VP3-VP1 cleavage sites were determined to be Q-H and Q-T, respectively, by N-terminal amino acid sequence analyses using purified virion proteins. Possible cleavage sites, Q-G, Q-A, and Q-S, which cleave P2 and P3 polyproteins were found to be similar to those of picornaviruses. A dendrogram based on 3Dpol proteins indicated that Aichi virus is genetically distinct from the known six genera of picornaviruses including entero-, rhino-, cardio-, aphtho-, and hepatovirus and echovirus 22. Considering this together with other properties of the virus (T. Yamashita, S. Kobayashi, K. Sakae, S. Nakata, S. Chiba, Y. Ishihara, and S. Isomura, J. Infect. Dis. 164:954–957, 1991), we propose that Aichi virus be regarded as a new genus of the family Picornaviridae. 相似文献