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1.
We have shown previously that the plant cannabinoid cannabidiol (CBD) elevates intracellular calcium levels in both cultured hippocampal neurones and glia. Here, we investigated whether the main psychotropic constituent of cannabis, Δ9-tetrahydrocannabinol (THC) alone or in combination with other cannabis constituents can cause similar responses, and whether THC affects the responses induced by CBD. Our experiments were performed with 1 μM pure THC (pTHC), with 1 μM pure CBD (pCBD), with a high-THC, low CBD cannabis extract (eTHC), with a high-CBD, low THC cannabis extract (eCBD), with a mixture of eTHC and eCBD (THC:CBD = 1:1) or with corresponding ‘mock extracts’ that contained only pTHC and pCBD mixed in the same proportion as in eTHC, eCBD or the 1:1 mixture of eTHC and eCBD.  相似文献   
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Background  

Hospital episode statistics (HES) is a UK national database for the National Health Service (NHS), now available online. The purpose of this study was to observe trends in ophthalmic operations performed during the period from 1998 to 2004, using this data.  相似文献   
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Thirty-nine primary surgical cases for correction of congenital aural atresia were reviewed for complications and long-term hearing results. Hearing averages of 25 dB for mild atresia, 40 dB for moderate atresia, and 46 dB for severe atresia were obtained. Serviceable hearing was achieved in 64% of the cases. The two most frequent complications were stenosis and recurrent infections of the cavity and canal skin, with an incidence of 33% and 31%, respectively. Use of split-thickness instead of full-thickness skin graft was associated with fewer complications. The goal of this review is also to share the experience of the senior author in the management of this complex problem.  相似文献   
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The aim of this series of experiments was to determine whether attention is normally required for continuously processing vestibular information concerning orientation, or is required only when orientation is disrupted (eg by vestibular dysfunction or by conflicting visual and vestibular orientation cues). In the first two studies, healthy subjects were passively oscillated, and indicated when they perceived they were passing through their starting position. There was only weak evidence for interference between performance on this 'continuous orientation monitoring task' and on concurrent mental tasks. However, a third study showed that when patients with vestibular imbalance carried out the continuous orientation monitoring task their performance on a concurrent mental arithmetic task was substantially impaired. This dual task interference was correlated with inaccuracy in judging orientation on the continuous orientation monitoring task, which in turn correlated with severity of recent vestibular symptomatology (assessed by questionnaire). In a fourth experiment, disorientation was induced in healthy subjects by rotating the visual field about the line of sight. Bidirectional interference was observed between monitoring orientation (assessed by accuracy in setting a rod to the perceived vertical) and performance of an arithmetic task. Dual task interference was correlated with baseline levels of disorientation induced by the visual field, as indicated by inaccuracy in judging the visual vertical. These findings suggest that monitoring orientation makes significant demands upon cortical processing resources when disorientation is induced, whether the disorientation results from deficient sensory functioning or from ambiguous perceptual information.  相似文献   
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Background  

To determine patterns of childhood lead exposure in a community living near a lead and zinc smelter in North Lake Macquarie, Australia between 1991 and 2002.  相似文献   
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Isolated rat livers were perfused with an immunoglobulin-free fluid containing homologous rat erythrocytes suspended in an isotonic saline solution. Galactosamine hepatitis and alpha-naphthylisothiocyanate cholestasis were induced as experimental liver diseases. The glutamic oxalacetic transaminase (GOT) and guanosine triphosphate (GPT) activities, the potassium level as well as the redox quotients of lactate/pyruvate and beta-hydroxybutyrate/acetoacetate were determined as liver function parameters. Results: The same dose of galactosamine led to two different types of reaction. The group suffering more damage (rendering maximum GOT activities) phagocytosed significantly (p less than or equal to 0.05) more erythrocytes than the other group. Galactosamine hepatitis significantly slows down the phagocytosis of erythrocytes. The function of the mononuclear phagocytosing cells in the liver is intact. The alpha-naphthylisothiocyanate (ANIT) cholestasis significantly reduces the capacity of the mononuclear phagocytosing cells in the liver. Young erythrocytes were phagocytosed significantly better than old ones in either type of liver damage, in galactosamine hepatitis and in ANIT cholestasis as well as by healthy livers.  相似文献   
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1Introduction Substanceabusecontinuestobeamongthemostsevereso cialandcostlyhealthproblemsdevastatingindividualsandtheir familiesintheUnitedStates.Initssimplestdefinition,sub stanceabuseisthecontinueduseofalcoholorotherdrugsde spiteknowledgeofhavingapersistentsocial,vocational,psy chologicalorphysicalproblemthatiscausedorexacerbatedby theuseofalcoholorotherdrugs(DSMIV TR,1994).All drugsofabuse,includingalcohol,aretoxicandcannegatively impacteverysysteminthehumanorganism.Protractedsub stance…  相似文献   
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