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61.
BACKGROUND: A systematic approach to determining drug intoxication has been developed for use by police officers. By considering specific physiological signs, trained officers can detect the effects of seven major drug types. METHODS: Officers follow a 12-step testing sequence and evaluate signs such as pupil sizes and responses, eye movements, heart rate, body temperature, mental timing, and balance. A matrix is then used to compare that subject's signs to those that would be produced by the seven types of drugs. If a pattern match is found, the officer concludes that the subject is under the influence of a drug and specifies the drug type. RESULTS: Several field and laboratory validation studies have been conducted using these procedures. In general, officers were 70% to 90% accurate in determining intoxication status and drug classification, but poly-drug use and drug rebound effects can sometimes cause problems in interpretation. CONCLUSION: Ocular and other physiological signs can be used to detect drug intoxication and classify the type of drug taken. Knowledge of the procedures used in the Drug Recognition Program can enable optometrists to serve as consultants to the police and as expert witnesses in cases involving the use of ocular signs that indicate illicit drug use.  相似文献   
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It was observed previously that ceramic/ceramic bilayers were very sensitive with respect to the electronic stopping power Se, i.e. strong interface mixing, scaling with , occurred if a threshold Sec was exceeded. The threshold seemed to be determined by the higher track formation threshold of two constituents forming the bilayer. Although no track formation has been observed in crystalline Si even for Uranium projectiles, interface mixing was observed previously for some Si-multilayers.

In this paper we report on the interface mixing of NiO, Fe2O3, TiO2 on Si due to irradiation with 90–350 MeV Ar-, Kr-, Xe- and Au-ions at 80 K at fluences up to 9E15 ions/cm2. Interface mixing, analyzed by means of Rutherford Backscattering Spectrometry (RBS), is found for these bilayers, too. But the threshold for intermixing is significantly higher compared to the ceramic/ceramic bilayers. This observation could be an evidence for the threshold being determined by the Si-layer. In contrast to NiO/Si and Fe2O3/Si, where an usual random walk mixing Δσ2 =  was observed, the interface broadening Δσ2 for TiO2/Si is found to scale nonlinearly with the ion fluence, which indicates that mixing is driven by a chemical solid-state reaction. At higher fluences plateaus form at the low energy Ni-edge of the RBS spectra. The plateaus indicate phase formation. X-Ray diffraction spectra does not show any evidence for new crystalline phases.  相似文献   

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Cytokines can be engineered for greater potency in stimulating cellular functions. An obvious test criterion for an improved cytokine is receptor-binding affinity, but this does not always correlate with improved biological response. By combining protein-engineering techniques with studies of receptor trafficking and signaling, it might be possible to identify the ligand receptor-binding properties that should be sought.  相似文献   
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Upon fractionation of a post mitochondrial supernatant from rat liver, phosphorylase kinase activity was largely recovered in the cytosol and the smooth endoplasmic reticulum (SER) fraction. The presence of phosphorylase kinase in SER vesicles was not due to an interaction of the enzyme with glycogen particles, since previous elimination of SER glycogen either by 48 h animal starvation or by treatment of the membrane fraction with alpha-amylase did not significantly alter phosphorylase kinase activity content. Washing of the initial pellet of SER fraction (crude SER) by dilution and recentrifugation, released in the supernatant an amount of phosphorylase kinase activity, which is dependent on: i) the degree of dilution, ii) the number of washes, iii) the ionic strength of the washing solution and iii) the presence or absence of Ca2+. Crude SER-associated phosphorylase kinase was marginally affected by increased concentrations of antibody against rabbit skeletal muscle holoenzyme which nevertheless drastically inhibited cytosolic enzyme activity, while it showed a higher resistance to partial proteolysis and a different Western blotting profile with anti-phosphorylase kinase when compared with the soluble kinase. A small but significant fraction of SER phosphorylase kinase was strongly associated with the microsomal fraction being partly extractable only in presence of detergents. This membrane-bound enzyme form exhibited an alkaline pH optimum, in contrast to the neutral pH optima of both soluble and weakly associated phosphorylase kinase.  相似文献   
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Meperidine is a synthetic opioid analgesic frequently prescribed in the emergency department. Meperidine is most often administered intramuscularly or intravenously, due to its poor oral bioavailability, and is metabolized extensively by the liver. Analgesic effects usually last 3-4 hours with parenteral administration, and some adverse effects such as nausea may be reduced when meperidine is combined with antiemetic or antihistaminic medications. Although meperidine is often a preferred analgesic by both patients and physicians in the treatment of disorders such as migraine headaches, its analgesic efficacy has rarely proven superior to alternative parenteral pain medications in controlled trials. In addition, meperidine can precipitate monoamine oxidase inhibitor reactions, and during metabolism it is demethylated to normeperidine, a compound with significant central nervous system (CNS) toxicity. Meperidine should be considered a second line agent in the treatment of pain when opioid analgesics are required.  相似文献   
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