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The effects of a crude extract of the stem bark of Cassia abbreviata on mean arterial pressure in anaesthetized rats were investigated. Bolus injections of the stem bark elicited a transitory fall in blood pressure which was dose-dependent. The depressor response was not blocked by atropine nor propranolol thus indicating that muscarinic and beta 2 receptors are not involved. However it was partially blocked by diphenhydramine, and H1 antagonist. The latter also partially blocked the depressor response to histamine which is mediated partially through both H1 and H2 receptors. It is concluded that the stem bark of C. abbreviata contains histamine or a chemically related substance and that it is this component which is responsible for lowering the blood pressure.  相似文献   
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BACKGROUND: The determination of age at the time of death is an important method in forensic anthropology and paleodemography. The possible postmortem investigation of the teeth and jaws enables the determination of age at the time of death, as the bones and teeth are both resistant to degradation in soil and characterized by age-related morphological changes. The aim of this study was to determine whether the age-related changes visible on panoramic radiography correlated with age, and enabled the assessment of individual age. METHODS: Seven radiographic parameters were used in the study: tooth loss, occlusal tooth wear, pulp stones, carious teeth, periapical disease, tooth restoration, and alveolar bone loss associated with periodontal disease. RESULTS: The material comprised 314 dental panoramic tomograms of living patients of both sexes with documented age (18 to 77 years). Multiple regression equations were constructed for the age estimation, including four parameters (the number of missing teeth, the number of intact teeth, the distance of cement-enamel junction from the alveolar ridge, the number of abraded teeth). The nature of data treated by regression analysis required the careful choice of parameters, appropriate functional model for each parameter, and the experience of the investigator. With the four parameters included in equations, the error was +/- 2.55 years. CONCLUSION: This preliminary analysis showed that the conventional regression technique could be appropriate for the age estimation based on panoramic radiography, and that an additional study with a larger sample and on wider population was required.  相似文献   
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Context  Although impunity for those responsible for trauma is widely thought to be associated with psychological problems in survivors of political violence, no study has yet investigated this issue. Objective  To examine the mental health and cognitive effects of war trauma and how appraisal of redress for trauma and beliefs about justice, safety, other people, war cause, and religion relate to posttraumatic stress responses in war survivors. Design, Setting, and Participants  A cross-sectional survey conducted between March 2000 and July 2002 with a population-based sample of 1358 war survivors who had experienced at least 1 war-related stressor (combat, torture, internal displacement, refugee experience, siege, and/or aerial bombardment) from 4 sites in former Yugoslavia, accessed through linkage sampling. Control groups at 2 study sites were matched with survivors on sex, age, and education. Main Outcome Measures  Semi-structured Interview for Survivors of War, Redress for Trauma Survivors Questionnaire, Emotions and Beliefs After War questionnaire, Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Results  The mean (SD) age was 39 (12) years, 806 (59%) were men, and 339 (25%) had high school or higher level of education. Participants reported experiencing a mean of 12.6 war-related events, with 292 (22%) and 451 (33%) having current and lifetime posttraumatic stress disorder (PTSD), respectively, and 129 (10%) with current major depression. A total of 1074 (79%) of the survivors reported a sense of injustice in relation to perceived lack of redress for trauma. Perceived impunity for those held responsible for trauma was only one of the factors associated with sense of injustice. Relative to controls, survivors had stronger emotional responses to impunity, greater fear and loss of control over life, less belief in benevolence of people, greater loss of meaning in war cause, stronger faith in God, and higher rates of PTSD and depression. Fear and loss of control over life were associated with PTSD and depression (odds ratio [OR], 2.91; 95% CI, 2.27-3.74 and OR, 2.30; 95% CI, 1.75-3.03, respectively), and emotional responses to impunity showed a relatively weaker association with PTSD (OR, 1.53; 95% CI, 1.16-2.02) and depression (OR, 1.39; 95% CI, 1.02-1.91). Appraisal of redress for trauma was not associated with PTSD or depression. Conclusions  PTSD and depression in war survivors appear to be independent of sense of injustice arising from perceived lack of redress for trauma. Fear of threat to safety and loss of control over life appeared to be the most important mediating factors in PTSD and depression. These findings may have important implications for reconciliation efforts in postwar countries and effective interventions for traumatized war survivors.   相似文献   
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Neuronal nicotinic acetylcholine receptor of the alpha 4/non-alpha (alpha 4/n alpha) type was reconstituted in Xenopus oocytes after nuclear injection of cDNA expression vectors. Functional neuronal receptor was only formed when the two subunits alpha 4 and n alpha were coinjected, neither alpha 4 nor n alpha alone being effective. Responses to bath application of acetylcholine (AcCho) have been measured in voltage clamp. AcCho doses as low as 10 nM induce currents of up to 50 nA. Dose-response studies indicate a Kd of about 0.77 x 10(-6) M and a Hill coefficient of 1.5, thus predicting more than one AcCho binding site per receptor molecule. The current-voltage relationship of AcCho-induced currents presents a strong inward rectification. Responses to AcCho were compared to those of three other agonists: L-nicotine, carbachol, and 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP). Sensitivities to AcCho, nicotine, and DMPP are quite similar. Sensitivity to carbachol is much lower, but the currents are otherwise indistinguishable from those induced by AcCho. Five AcCho antagonists--neuronal bungarotoxin (kappa-bungarotoxin), tubocurarine (TC), hexamethonium bromide (Hex), decamethonium bromide (Dec), and mecamylamine (Mec)--have been tested. Neuronal bungarotoxin has no effect on the alpha 4/n alpha channel, whereas 2.5 microM TC reduces by half the current peak evoked by 1 microM AcCho. The block by TC is independent of membrane voltage. By contrast, the block of AcCho-induced currents by Hex or Dec is strongly voltage dependent, suggesting that these substances enter the channel. The block by Mec is detectable at concentrations as low as 100 nM when applied together with 1 microM AcCho and is voltage independent. Hex, Dec, and Mec are effective only when AcCho is present. While the effects of all other agents are fully reversible, the Mec block is persistent.  相似文献   
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Locally manufactured sodium hypochlorite (chlorine) solution has been sold in Zimbabwe since 2010. During October 1, 2011–April 30, 2012, 4,181 suspected and 52 confirmed cases of typhoid fever were identified in Harare. In response to this outbreak, chlorine tablets were distributed. To evaluate household water treatment uptake, we conducted a survey and water quality testing in 458 randomly selected households in two suburbs most affected by the outbreak. Although 75% of households were aware of chlorine solution and 85% received chlorine tablets, only 18% had reportedly treated stored water and had the recommended protective level of free chlorine residuals. Water treatment was more common among households that reported water treatment before the outbreak, and those that received free tablets during the outbreak (P < 0.01), but was not associated with chlorine solution awareness or use before the outbreak (P > 0.05). Outbreak response did not build on pre-existing prevention programs.  相似文献   
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