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In spite of great advances in medicine, serious communicable diseases are a significant threat. Hospitals must be prepared to deal with patients who are infected with pathogens introduced by a bioterrorist act (e.g., smallpox), by a global emerging infectious disease (e.g., avian influenza, viral hemorrhagic fevers), or by a laboratory accident. One approach to hazardous infectious diseases in the hospital setting is a biocontainment patient care unit (BPCU). This article represents the consensus recommendations from a conference of civilian and military professionals involved in the various aspects of BPCUs. The role of these units in overall U.S. preparedness efforts is discussed. Technical issues, including medical care issues (e.g., diagnostic services, unit access); infection control issues (e.g., disinfection, personal protective equipment); facility design, structure, and construction features; and psychosocial and ethical issues, are summarized and addressed in detail in an appendix. The consensus recommendations are presented to standardize the planning, design, construction, and operation of BPCUs as one element of the U.S. preparedness effort.  相似文献   
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We describe here a new method for specific staining of mast cells using ferroin. Different hamster tissues were fixed in 4% formalin and processed for paraffin embedding. Sections were stained with hematoxylin followed by ferroin acidified with 2.5 N sulfuric acid to pH 4.0. Mast cells stained an intense orange color that contrasted markedly with bluish violet nuclei. High contrast was also observed when ferroin colored sections were counterstained with light green instead of hematoxylin. To evaluate the specificity of the stain, hamster cheek pouch sections were stained with toluidine blue, alcian blue-safranin O, and ferroin. Quantitative evaluation of mast cells stained with the three techniques showed no statistical difference. The simplicity and selectivity of this method is sufficient for image analysis of mast cells.  相似文献   
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The Malacca tilapia hybrids   总被引:1,自引:0,他引:1  
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Li Y  Lenaghan SC  Zhang M 《PloS one》2012,7(2):e31724
In drug delivery, there is often a trade-off between effective killing of the pathogen, and harmful side effects associated with the treatment. Due to the difficulty in testing every dosing scenario experimentally, a computational approach will be helpful to assist with the prediction of effective drug delivery methods. In this paper, we have developed a data-driven predictive system, using machine learning techniques, to determine, in silico, the effectiveness of drug dosing. The system framework is scalable, autonomous, robust, and has the ability to predict the effectiveness of the current drug treatment and the subsequent drug-pathogen dynamics. The system consists of a dynamic model incorporating both the drug concentration and pathogen population into distinct states. These states are then analyzed using a temporal model to describe the drug-cell interactions over time. The dynamic drug-cell interactions are learned in an adaptive fashion and used to make sequential predictions on the effectiveness of the dosing strategy. Incorporated into the system is the ability to adjust the sensitivity and specificity of the learned models based on a threshold level determined by the operator for the specific application. As a proof-of-concept, the system was validated experimentally using the pathogen Giardia lamblia and the drug metronidazole in vitro.  相似文献   
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Infertility affects one in seven couples globally and has recently been classified as a disease by the World Health Organisation (WHO). While in-vitro fertilisation (IVF) offers effective treatment for many infertile couples, cases exhibiting severe male infertility (19?C57%) often remain difficult, if not impossible to treat. In such cases, intracytoplasmic sperm injection (ICSI), a technique in which a single sperm is microinjected into the oocyte, is implemented. However, 1?C5% of ICSI cycles still fail to fertilise, affecting over 1000 couples per year in the UK alone. Pregnancy and delivery rates for IVF and ICSI rarely exceed 30% and 23% respectively. It is therefore imperative that Assisted Reproductive Technology (ART) protocols are constantly modified by associated research programmes, in order to provide patients with the best chances of conception. Prior to fertilisation, mature oocytes are arrested in the metaphase stage of the second meiotic division (MII), which must be alleviated to allow the cell cycle, and subsequent embryogenesis, to proceed. Alleviation occurs through a series of concurrent events, collectively termed ??oocyte activation??. In mammals, oocytes are activated by a series of intracellular calcium (Ca2+) oscillations following gamete fusion. Recent evidence implicates a sperm-specific phospholipase C, PLCzeta (PLC??), introduced into the oocyte following membrane fusion as the factor responsible. This review summarises our current understanding of oocyte activation failure in human males, and describes recent advances in our knowledge linking certain cases of male infertility with defects in PLC?? expression and activity. Systematic literature searches were performed using PubMed and the ISI-Web of Knowledge. Databases compiled by the United Nations and World Health Organisation databases (UNWHO), and the Human Fertilization and Embryology Authority (HFEA) were also scrutinised. It is clear that PLC?? plays a fundamental role in the activation of mammalian oocytes, and that genetic, molecular, or biochemical perturbation of this key enzyme is strongly linked to human infertility where oocyte activation is deficient. Consequently, there is significant scope for our understanding of PLC?? to be translated to the ART clinic, both as a novel therapeutic agent with which to rescue oocyte activation deficiency (OAD), or as a prognostic/diagnostic biomarker of oocyte activation ability in target sperm samples.  相似文献   
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