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991.
W. R. Law R. F. Ritzmann J. M. Lee M. A. Kapin J. L. Ferguson 《Cellular and molecular life sciences : CMLS》1985,41(1):78-80
Summary Both acute and chronic administration of morphine resulted in an increase in the percent cardiac output received by brain. However, various brain regions were affected differently by the drug treatments. The greatest increases in percent cardiac output received after chronic administration of morphine occurred in pons and cerebellum, while the greatest increases after acute administration occurred in cortex and midbrain. The changes found are in contrast with earlier studies which suggest that morphine has no effect on cerebral blood flow. 相似文献
992.
993.
In-Sook Lee 《Systemic Practice and Action Research》1995,8(3):263-276
In recent decades, there has been increased awareness of the need for systemic change in education. In systemic change, it is of the greatest importance that stakeholders examine and clarify their individual values and articulate shared values and state them clearly. This is necessary because values underlie visions, guide choices, decisions, and actions made in the course of design and, eventually, serve as practical tools in evaluating a system and its programs. This study explores the importance of articulating values in the design of educational systems. Given the importance of the clarification of values consented to by stakeholders and the lack of previous in-depth studies, the paper concludes that it is urgent to develop systemic and comprehensive value categories to aid in articulating core values and to serve as guidelines for applying these values in educational systems design. 相似文献
994.
Zusammenfassung Die Insulinwirkung auf die Magensäuresekretion wurde in männlichen Sprague-Dawley Ratten untersucht, deren Pylorus 2 h vorher unterbunden war. Eine Dosis-Wirkungskurve wurde aufgestellt. Maximale Sekretion von Magensäure und Magensaft wurden durch s.c. Injektion von 4 Einheiten krystallinischen Zink-Insulins per 100 g Körpergewicht erzielt. Grössere Dosen von Insulin unterdrücken Säure- und Magensaftsekretion. Das Verhalten der Elektrolyte im Magensaft spricht sowohl für die Neutralisierungs-Verdünnungshypothese als auch für die Austausch-Diffusionshypothese zur Erklärung der Magensaftproduktion. 相似文献
995.
R. G. Nagele J. F. Pietrolungo H. Lee 《Cellular and molecular life sciences : CMLS》1981,37(3):304-306
Summary Coated vesicles were found to accumulate Ca++ in neuroepithelial cells and may play a role in regulating the contractile activities of apical microfilament bundles during uplifting of neural folds in the chick.This study was supported in part by grants from the Research Council and the Charles and Johanna Busch Memorial Fund of Rutgers University. 相似文献
996.
Distribution of tunichrome and vanadium in sea squirt blood cells sorted by flow cytometry 总被引:1,自引:0,他引:1
E M Oltz S Pollack T Delohery M J Smith M Ojika S Lee K Kustin K Nakanishi 《Experientia》1989,45(2):186-190
Specialized blood cells of many tunicates accumulate high concentrations of vanadium and phenolic peptide pigments called tunichromes (TC). In order to determine whether V and TC reside in the same cells, Ascidia nigra and Ascidia ceratodes blood cell subpopulations were isolated by fluorescence-activated cell sorting (flow cytometry) and chemically analyzed. V was found in the spherical, green/grey signet ring cells, and to a lesser degree in the mulberry-shaped, yellow/green morula cells (MRs), whereas free TC was detected mainly in MRs. 相似文献
997.
应用~3H-TdR光镜和电镜放射自显影观察表明,MGc80-3 细胞标记指数达31.51%,标记银粒集中于分裂间期的S期细胞核中,细胞核呈重标记状态,绝大多数标记银粒分布于细胞核常染色质区域,少数见于核孔附近的常染色质或核孔附近的细胞质中,核仁未见标记,显示细胞内 DNA合成十分活跃。但经 dBcAMP诱导后,标记指数则降至 4.35%,细胞核呈弱标记状态,电镜放射自显影则未在细胞核内见到标记银粒,表明其DNA合成受到明显抑制。这种变化是由于dBcAMP诱导胃癌细胞内cAMP水平提高而实现的,认为DNA合成抑制是导致MGc80-3细胞走向分化的一个重要原因,对于癌变细胞恶性表型逆转具有重要作用。 相似文献
998.
A number of IDSs have been proposed for a networked or distributed environment. A modified DIDS using federated peertopeer architecture, MCR (Multicast Reflector) and modified shaker protocol were proposed. The suggested scheme can be implemented easily and performs the information sharing between lowlevel IDS agents. As all users within a group monitor each other's, the common control server can perform detect intrusions with less cost and support the detection of the inside intruders. 相似文献
999.
HSIAO Taichung LEE Bingjean CHOU Tienyin LIEN Huipain CHANG Yinghuei 《武汉大学学报:自然科学英文版》2007,12(4):610-618
Since 2002,the Soil and Water Conservation Bureau,which is responsible for the conservation and administrative man-agement of hillside in Taiwan,has been cooperating with Feng Chia University. Together,they have successfully carried out the establishment and maintenance of 13 fixed debris flow monitoring stations over the island and 2 mobile debris flow monitoring sta-tions. During July 2004,a powerful southwest air current brought by Mindulle Typhoon caused serious flood in central and southern Taiwan. This paper aims to describe the establishment of debris flow monitoring systems in Taiwan and the observation of the debris flow event during Mindulle Typhoon at Aiyuzi River in Shenmu Village,Nantou County by the monitoring station. 相似文献
1000.
Mice deficient for corticotropin-releasing hormone receptor-2 display anxiety-like behaviour and are hypersensitive to stress 总被引:21,自引:0,他引:21
Bale TL Contarino A Smith GW Chan R Gold LH Sawchenko PE Koob GF Vale WW Lee KF 《Nature genetics》2000,24(4):410-414
Corticotropin-releasing hormone (Crh) is a critical coordinator of the hypothalamic-pituitary-adrenal (HPA) axis. In response to stress, Crh released from the paraventricular nucleus (PVN) of the hypothalamus activates Crh receptors on anterior pituitary corticotropes, resulting in release of adrenocorticotropic hormone (Acth) into the bloodstream. Acth in turn activates Acth receptors in the adrenal cortex to increase synthesis and release of glucocorticoids. The receptors for Crh, Crhr1 and Crhr2, are found throughout the central nervous system and periphery. Crh has a higher affinity for Crhr1 than for Crhr2, and urocortin (Ucn), a Crh-related peptide, is thought to be the endogenous ligand for Crhr2 because it binds with almost 40-fold higher affinity than does Crh. Crhr1 and Crhr2 share approximately 71% amino acid sequence similarity and are distinct in their localization within the brain and peripheral tissues. We generated mice deficient for Crhr2 to determine the physiological role of this receptor. Crhr2-mutant mice are hypersensitive to stress and display increased anxiety-like behaviour. Mutant mice have normal basal feeding and weight gain, but decreased food intake following food deprivation. Intravenous Ucn produces no effect on mean arterial pressure in the mutant mice. 相似文献