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91.
拖拉机行驶路线的自动变更研究 总被引:3,自引:3,他引:0
为了实现拖拉机自动化作业的需要,本研究利用前馈控制和反馈控制相结合的控制方法,设计了拖拉机行驶路线自动变更的非线性反馈控制器。首先,利用非线性最优控制方法,设计了车辆进行行驶路线自动变更的基准轨迹;然后利用LQ最优控制技术,构造了车辆沿着基准轨迹进行行驶路线变更的反馈控制器。最后,利用设计的基准轨迹和反馈控制器进行了实车试验。试验表明,该控制方法具有良好的适应性,所设计的控制器具有良好的响应性和收敛性。 相似文献
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Satoshi Kitao Takatsugu Yamada Takefumi Ishikawa Hiroo Madarame Mitsuru Furuichi Sakurako Neo Ryo Tsuchiya Kosaku Kobayashi 《Journal of veterinary diagnostic investigation》2006,18(3):291-295
Serum alpha-fetoprotein (AFP) concentrations were measured before and after surgical removal of tumor masses in four dogs with hepatocellular carcinoma (HCC). Localization of AFP was also examined immunohistochemically in tumor tissues. In three cases, the serum AFP concentration was 10 to 20 times higher than that of normal dogs. One to two months after surgery, the serum AFP concentration had decreased to normal range. AFP was localized in the tumor tissues in these three cases. One case, which had a low serum AFP, did not show AFP localization in tumor tissue. 相似文献
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Progesterone stimulation by LH involves the phospholipase-C pathway in bovine luteal cells 总被引:2,自引:0,他引:2
Nishimura R Shibaya M Skarzynski DJ Okuda K 《The Journal of reproduction and development》2004,50(2):257-261
Luteinizing hormone (LH)-stimulated steroidogenesis in luteal cells is known to be mediated through the activation of cyclic AMP (cAMP)-dependent protein kinase, and to be also modulated by calcium-dependent mechanisms. In the present study, we tested the hypothesis that LH stimulates progesterone (P4) production in bovine luteal cells through activation of phospholipase (PL) C by using a cell culture system. Bovine mid-luteal cells (Days 8-12 of the estrous cycle) were cultured for 24 h and then exposed to a PLC inhibitor (U-73122; 10 microM) with or without LH (10 ng/ml) for 4 h. U-73122 blocked LH-stimulated P4 production without affecting cAMP accumulation. Moreover, exposure of luteal cells to PLC increased P4 production in a dose-dependent manner. These results support the hypothesis that the luteotropic action of LH in bovine luteal cells is mediated not only by activation of adenylate cyclase but also by activation of PLC. 相似文献
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Shuji Takeda Hiroyuki Asano Ryo Ihara Keiko Ogata Masahiko Kushida 《Journal of toxicologic pathology》2014,27(2):143-146
Oligodendroglioma is a rare tumor originating from oligodendrocytes found mainly in the cerebrum in aged rats. Only a few reports have shown spontaneous occurrence of this tumor in the spinal cord, and no report has mentioned its occurrence in young rats. We encountered a case of spontaneous oligodendroglioma in the lumbar portion of the spinal cord in a young (9 weeks old) female BrlHan:WIST@Jcl (GALAS) rat. Here we report the detailed histopathological and immunohistochemical characteristics of this case. No clinical signs, no gross lesions at necropsy, and no specific changes in hematology or blood biochemistry were observed. The tumor was located in the dorsal funiculus in the lumbar portion of the spinal cord and widely spread to the dorsal root nerve. The neoplastic cells showed a sheet-like growth pattern and had small round nuclei, clear cytoplasm and distinct cell borders that resulted in a honeycomb pattern. No mitotic figures or other histological lesions were observed. The neoplastic cells were positively stained for Olig2 and PCNA. The present case was considered to be a low-grade oligodendroglioma based on the histological and immunohistochemical features. To our knowledge, our case is considered to be extremely rare and the first report in a young rat. 相似文献
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Yasumitsu MASUDA Ryo HASEBE Yasushi KUROMI Masayoshi KOBAYASHI Misaki IWAMOTO Mitsugu HISHINUMA Tetsuya OHBAYASHI Ryo NISHIMURA 《The Journal of reproduction and development》2021,67(2):149
While embryo transfer (ET) is widely practiced, many of the transferred embryos fail to develop in cattle. To establish a more effective method for selecting bovine embryos for ET, here we quantified morphological parameters of living embryos using three-dimensional (3D) images non-invasively captured by optical coherence tomography (OCT). Seven Japanese Black embryos produced by in vitro fertilization that had reached the expanded blastocyst stage after 7 days of culture were transferred after imaged by OCT. Twenty-two parameters, including thickness and volumes of the inner cell mass, trophectoderm, and zona pellucida, and volumes of blastocoel and whole embryo, were quantified from 3D images. Four of the seven recipients became pregnant. We suggest that these 22 parameters can be potentially employed to evaluate the quality of bovine embryos before ET. 相似文献