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31.
A drinking water supply is a complicated system in its construction,operation,maintenance and need for public health surveillance.  相似文献   
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A provisional set of standards of care was derived from a quality assurance strand of a wider research project, which reported the development of evaluation strategies for area integrated mental health services (AIMHS). In contrast to most published standards, they apply to all facets of care in a comprehensive catchment area mental health service, whether clinical or functional, community or hospital based, urban or rural, or managed by the public, private or voluntary sectors. We review briefly existing sets of standards of mental health services and report the process of development of standards of care, each with sub-sets of performance indicators and examples. While the AIMHS standards and a companion quality assurance manual are still undergoing refinement, they offer a guide for mental health professionals to the provision of services, and a checklist to service-users of services that should be available to them at every stage of care in a mental health system.  相似文献   
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The importance of the respiratory system to total body functioning cannot be overemphasized. It is imperative that the nurse realize that the first priority in trauma care is to maintain and support the respiratory system. The nurse must be able to rapidly and effectively perform a primary survey, recognize the clinical manifestations of life-threatening thoracic injuries, and intervene in the care of the patient to help stabilize and maintain the patient's respiratory function. The nurse must not only be able to asses, but must also be able to technically intervene rapidly and effectively. Other potential life-threatening injuries must remain uppermost in the nurse's mind. Continual, ongoing monitoring of the patient's status must be an integral part of the nurse's actions. If these activities are judiciously employed, perhaps the mortality rate will decrease and the thoracic trauma victim will survive, capable of leading a full and productive life in our society. This is quality patient care.  相似文献   
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A 58-year-old man with a pectus excavatum demonstrated a photon-deficient defect within the left lobe of the liver on liver-spleen scintigraphy using Tc-99m SCOL. Computed tomography of the liver clearly revealed the abnormal defect seen on the liver-spleen scan to be due to the pectus excavatum. This case confirms the impression that these skeletal aberrations may cause false-positive hepatic defects.The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense  相似文献   
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Invasion of the reconstituted extracellular matrix composite, Matrigel, by eight human glioma–derived cell lines and human fetal brain cells was assessed in vitro using 8 um polycarbonate filters in a modified Boyden migration chamber. With the exception of one low grade glioma derived cell line, all lines studied proved to be invasive while normal fetal brain cells failed to invade. This invasive potential was independent of the histological grade of the tumour from which the cell lines originated. In addition, the expression of the metastasis–associated gene 18A2lmts1 as well as the tissue inhibitor of metalloproteinases–2 (TIMP–2) was analysed in each of the glioma–derived cell lines. The 18A2/mtsl was expressed in all the cells studied with the exception of fetal brain cells and the low grade non–invasive glioma derived IPRK–7 cell line. The 18A2/mtsl related genes coding for the S100 subfamily of calcium binding proteins were found to be differentially and overexpressed in invasive cell lines. TIMP–2 was expressed only in noninvasive cell lines. These results suggest that the 18A2/ mtsl and TIMP–2 genes could play an important role in the invasive behaviour of human glioma cells in vitro. .  相似文献   
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Sonoelasticity is the use of ultrasonography to visualize, in real time, the hardness of stiffness of tissues and organs by depicting the tissue's motion in response to an applied vibration source. The applied vibration source is usually of low amplitude and low frequency (less than 0.1 mm displacement and less than 2000 Hz). Under these conditions, the natural vibration response of tissues and whole organs is revealed as a standing wave pattern determined by the low-frequency elastic constants of the tissues and their boundary conditions, factors that are not related to the ultrasonic echogenicity. As a result, hard or dense isoechoic tumors that are undetectable by conventional ultrasonography often can be visualized in sonoelasticity imaging by virtue of their altered vibration response. In this report, we demonstrate the appearance of organs such as the breast, liver, and kidney during real-time, in vivo sonoelasticity imaging. The results show that the shape and location of vibration patterns are dependent on the tissues and vibration frequencies; thus, information about the basic elastic properties of tissues should be obtainable.  相似文献   
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