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991.
Summary Aflatoxin and secalonic acid D production in corn in laboratory and field by mixed cultures ofPencillium oxalicum andAspergillus flavus orA. parasiticus was lower than production by the pure cultures. However, mixed culture of these molds withFusarium spp. did not affect mycotoxin production.  相似文献   
992.
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   
993.
994.
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   
995.
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   
996.
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   
997.
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   
998.
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   
999.
 A number of IDSs have been proposed for a networked or distributed environment. A modified DIDS using federated peertopeer architecture, MCR (Multicast Reflector) and modified shaker protocol were proposed. The suggested scheme can be implemented easily and performs the information sharing between lowlevel 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   
1000.
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   
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