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The primary purpose of these procedures is to demonstrate for teaching and research purposes how to record the activity of living primary sensory neurons responsible for proprioception as they are detecting joint position and movement, and muscle tension. Electrical activity from crustacean proprioceptors and tension receptors is recorded by basic neurophysiological instrumentation, and a transducer is used to simultaneously measure force that is generated by stimulating a motor nerve. In addition, we demonstrate how to stain the neurons for a quick assessment of their anatomical arrangement or for permanent fixation. Staining reveals anatomical organization that is representative of chordotonal organs in most crustaceans. Comparing the tension nerve responses to the proprioceptive responses is an effective teaching tool in determining how these sensory neurons are defined functionally and how the anatomy is correlated to the function. Three staining techniques are presented allowing researchers and instructors to choose a method that is ideal for their laboratory.  相似文献   
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ObjectivesTo examine whether self reported health status and use of health services varies in children of different social class and ethnic group.DesignCross sectional study from the 1999 health survey for England.Subjects6648 children and young adults aged 2-20 years.SettingPrivate households in England.ResultsLarge socioeconomic differences were observed between ethnic subgroups; a higher proportion of Afro-Caribbean, Indian, Pakistani, and Bangladeshi children belonged to lower social classes than the general population. The proportion of children and young adults reporting acute illnesses in the preceding two weeks was lower in Bangladeshi and Chinese subgroups (odds ratio 0.41, 95% confidence interval 0.27 to 0.61 and 0.46, 0.28 to 0.77, respectively) than in the general population. Longstanding illnesses was less common in Bangladeshi and Pakistani children (0.52, 0.40 to 0.67 and 0.57, 0.46 to 0.70) than in the general population. Irish and Afro-Caribbean children reported the highest prevalence of asthma (19.5% and 17.7%) and Bangladeshi children the lowest (8.2%). A higher proportion of Afro-Caribbean children reported major injuiries than the general population (11.0% v 10.0%), and children from all Asian subgroups reported fewer major and minor injuries than the general population. Indian and Pakistani children were more likely to have consulted their general practitioner in the preceding fortnight than the general population (1.86, 1.35 to 2.57 and 1.51, 1.13 to 2.01, respectively). Indian, Pakistani, Bangladeshi, and Chinese children were less likely to have attended outpatient departments in the preceding three months. No significant differences were found between ethnic groups in the admission of inpatients to hospitals. Acute and chronic illness were the best predictors of children''s use of health services. Social classes did not differ in self reported prevalence of treated infections, major injuries, or minor injuries, and no socioeconomic differences were seen in the use of primary and secondary healthcare services.ConclusionsChildren''s use of health services reflected health status rather than ethnic group or socioeconomic status, implying that equity of access has been partly achieved, although reasons why children from ethnic minority groups are able to access primary care but receive less secondary care need to be investigated.

What is already known on this topic

Children from lower socioeconomic classes and from Indian ethnic subgroups may make more use of general practitioners'' services than other childrenAfro-Caribbean, Indian, Pakistani, and Bangladeshi children are less likely to be referred to outpatient and inpatient services at hospitals than white children

What this study adds

Indian, Pakistani, and Bangladeshi children reported less acute and chronic illness, asthma, and injuries than the general population, whereas Afro-Caribbean children reported moreChildren''s self reported health status and use of health services did not vary by social classIndian and Pakistani children make more use of general practitioners'' services, but Indian, Pakistani, Bangladeshi, and Chinese children are less likely to be referred to outpatient clinicsSelf reported health status rather than socioeconomic status or ethnicity is the best predictor of use of primary and secondary services  相似文献   
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ObjectivesTo calculate socioeconomic and health status measures for the primary care groups in London and to examine the association between these measures and hospital admission rates.DesignCross sectional study.Setting66 primary care groups in London, total list size 8.0 million people.ResultsStandardised hospital admission ratios varied from 74 to 116 for total admissions and from 50 to 124 for emergency admissions. Directly standardised admission rates for asthma varied from 152 to 801 per 100 000 (mean 364) and for diabetes from 235 to 1034 per 100 000 (mean 538). There were large differences in the mortality, socioeconomic, and general practice characteristics of the primary care groups. Hospital admission rates were significantly correlated with many of the measures of chronic illness and deprivation. The strongest correlations were with disability living allowance (R=0.64 for total admissions and R=0.62 for emergency admissions, P<0.0001). Practice characteristics were less strongly associated with hospital admission rates.ConclusionsIt is feasible to produce a range of socioeconomic, health status, and practice measures for primary care groups for use in needs assessment and in planning and monitoring health services. These measures show that primary care groups have highly variable patient and practice characteristics and that hospital admission rates are associated with chronic illness and deprivation. These variations will need to be taken into account when assessing performance.  相似文献   
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Kudzu (Pueraria thunbergiana) plant extract impregnated sediments were used for abiotic and biotic uptakes and biodegradation. The optimized conditions were 25 μg L?1 concentration, 7 days for abiotic uptake and 56 days for biotic uptake and biodegradation, dose 2 g L?1, 7 pH, and 35°C temperature. The amount removed of dufulin was 32.6% in abiotic conditions while these were 90% in the case of biotic uptake and biodegradation. Enantioselective biodegradation indicated that S‐(+)‐enantiomer degraded faster (90%) than R‐(?)‐enantiomer (87%). The data for abiotic and biotic uptakes and biodegradation followed well Langmuir, thermodynamics, and kinetics models. All these processes followed pseudo first‐order kinetics. It was observed that biodegradation was three times responsible for dufulin removal than simple sorption uptake (abiotic and biotic). The abiotic and biotic uptakes and biodegradation were quite fast and endothermic nature. The developed method may be used to remove the racemic and enantiomeric dufulin in water.  相似文献   
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The study of functional brain connectivity alterations induced by neurological disorders and their analysis from resting state functional Magnetic Resonance Imaging (rfMRI) is generally considered to be a challenging task. The main challenge lies in determining and interpreting the large-scale connectivity of brain regions when studying neurological disorders such as epilepsy. We tackle this challenging task by studying the cortical region connectivity using a novel approach for clustering the rfMRI time series signals and by identifying discriminant functional connections using a novel difference statistic measure. The proposed approach is then used in conjunction with the difference statistic to conduct automatic classification experiments for epileptic and healthy subjects using the rfMRI data. Our results show that the proposed difference statistic measure has the potential to extract promising discriminant neuroimaging markers. The extracted neuroimaging markers yield 93.08% classification accuracy on unseen data as compared to 80.20% accuracy on the same dataset by a recent state-of-the-art algorithm. The results demonstrate that for epilepsy the proposed approach confirms known functional connectivity alterations between cortical regions, reveals some new connectivity alterations, suggests potential neuroimaging markers, and predicts epilepsy with high accuracy from rfMRI scans.  相似文献   
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