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41.
OBJECTIVE: Latency measurement of myoelectric deep tendon (T) reflex responses is not usually performed in EMG laboratories. We investigated the optimal conditions of reliable recording of T reflex in children and adults. METHODS: Two hundred and sixty-eight normal subjects (139 males, 129 females, age rank 2 days-80 years) were studied. T reflexes were recorded from soleus and rectus femoris muscles (children and adults) and from triceps brachialis, biceps brachialis and flexor carpi radialis (adults). Specially devised hammers were used. They were fitted with a spring switch system in order to trigger the trace display on the EMG machine. Distinct technical options for the synchronisation delay assessment were tested. The nerve conduction velocities along reflex pathways were computed by referring the T wave latencies to subject's height. RESULTS: Reliable recordings could be obtained in all cases, with a strong linear correlation of the response latency with height. T reflex conduction velocities increased as the log value of subject age. Normative data from birth to 80 years are provided. CONCLUSION: T reflex recording represents a painless and easily performed technique. It may be helpful for the assessment of proximal conduction velocities, especially in children during maturation of the peripheral nervous system.  相似文献   
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Monitoring of motor pathways via muscle contraction recording is sensitive to anesthetics, particularly volatile anesthetics. However, the specific action sites of these anesthetics on the spinal cord and the peripheral nervous system are not well known in humans. Therefore, we studied proximal and distal motor and sensory nerve conduction, neuromuscular junction transmission, and spinal cord excitability (H/M amplitude ratio and F-wave amplitude and persistency) using standard neurophysiological techniques in 10 patients who underwent orthopedic surgery. Muscle potentials evoked by spinal cord stimulation were recorded in five additional patients. Desflurane was introduced to achieve end-tidal concentration of 3.7% and 7.4%, in 50% O2/N2O and in 100% O2. Measurements were obtained before desflurane administration and 20 min after obtaining a stable level of each concentration. Peripheral nerve conduction and neuromuscular function were not significantly affected by desflurane. However, spinal cord excitability was significantly decreased by desflurane administration (H/M ratio 37% +/- 9%, 12% +/- 5%, 7% +/- 4% at desflurane concentration 0.0%, 3.7%, and 7.4% in 100% O2, respectively). Muscle potentials evoked by spinal cord stimulation were abolished by desflurane. These data rule out the possibility that desflurane specifically alters peripheral nerve conduction or synapse transmission at the neuromuscular junction. They demonstrate that desflurane acts preferentially at the level of the spinal motoneuron. Implications: We used neurophysiological techniques to assess the effects of desflurane on spinal cord conduction and excitability, motor and sensory peripheral nerve conduction, and neuromuscular transmission. Our data demonstrate that desflurane acts preferentially at the level of the spinal motoneuron, providing useful information for neurophysiological monitoring and immobilization during surgery and for minimum alveolar anesthetic concentration definition.  相似文献   
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ObjectiveAssessment of intravascular volume status to ensure optimization before hospital discharge could significantly reduce readmissions. It is difficult to evaluate congestion on clinical signs during an episode of acute heart failure (ADHF) in elderly patients.HypothesisThere is an association between various volume overload parameters in patients older than 75 years.MethodsWe performed a single‐center prospective longitudinal study of patients older than 75 years hospitalized for acute heart failure. We analyzed the association between congestion assessment based on clinical signs, inferior vena cava (IVC) diameter measured by ultrasound, biological evaluation with N terminal pro brain natriuretic peptide (NT‐proBNP), and estimated plasma volume (EPV) during decongestive therapy. We also monitored changes in renal function.ResultsFifty consecutive ADHF patients (85.2 ± 5.9 years, 68% female) were included in the study. At admission, a dilated, noncompliant IVC was found in all patients. The strongest correlations between different parameters of volume overload estimation were found between IVC and jugular vein distention (r = .8; p < .001), then IVC and oedema (r = .6; p < .001), IVC and crackles (r = .3; p < .036), then IVC and NT‐proBNP (r = .3; p = .02). There was no correlation between EPV and signs of congestion. Patients who had no congestive signs on clinical or IVC examination at Day 2, more often presented with acute renal failure.ConclusionIn ADHF patients older than 75 years, clinical and IVC evaluation of intravascular congestion correlate well. The concomitant assessment of clinical signs and IVC may prevent depletion‐related renal failure.  相似文献   
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There is little information about the relation between mild cardiac troponin I (cTn-I) increase after coronary interventions and late outcome. We therefore focused on the long-term outcome and the clinical, morphologic, and procedural correlates of elevation of cTn-I compared with cardiac troponin T, creatine kinase (CK), CK-MB activity and mass, and myoglobin in 105 patients with successful elective percutaneous transluminal coronary angioplasty (PTCA) for stable or unstable angina. Patients with myocardial infarction and those with unstable angina who had a detectable increase in serum markers before PTCA were excluded. Markers were measured before and after the procedure and for 2 days. Patients were followed up to record recurrent angina, myocardial infarction, cardiac death, repeat PTCA, or elective coronary artery bypass graft surgery. Procedure success was achieved in all cases. Elevation in cTn-I (> or =0.1 microg/L) was observed in 23 of 105 patients (22%) (median peak: 0.25 microg/L); 18% had cardiac troponin T (cTn-T) release (> or = 0.1 microg/L, median peak 0.21); 11.4% CK-MB mass (> or =5 microg/L), and 7.6% myoglobin (> or =90 microg/L) release. Five and 2 patients had elevated CK and CK-MB activity, respectively. Fourteen of 18 patients with cTn-T elevation had a corresponding elevation in cTn-I (kappa 0.68; p = 0.001). Patients positive for cTn-I had more unstable angina (p = 0.042) and heparin before PTCA (p = 0.046), and had longest total time (p = 0.004) and single inflation (p = 0.01). By multivariate logistic regression, predictors of postprocedure cTnI elevation were maximum time of each inflation (odds ratio 9.2; p = 0.0012), type B lesions (odds ratio 6.6; p = 0.013), unstable angina (p = 0.041), and age > or =60 years (p = 0.032). Clinical follow-up was available in 103 patients (98%) (mean 19+/-10 months). Kaplan-Meier survival analysis showed that cTn-I elevation was not an important correlate of cardiac events (p = 0.34, by log-rank analysis). The incidence of recurrent angina, myocardial infarction, cardiac death, and repeat revascularization after 12 months was not different in patients positive or negative for cTn-I. We conclude that cTn-I elevation after successful PTCA is not associated with significantly worse late clinical outcome. Levels of cTn-I allow a much higher diagnostic accuracy in detecting minor myocardial injury after PTCA compared with other markers, but there is no association with periprocedural myocardial cell injury and late outcome when cTn-I and other markers are considered.  相似文献   
46.
染色体脆性位点表达与Ⅱ型糖尿病关系的探讨曾平郭英周迎生一、对象与方法1995年5~12月,我们探讨了染色体脆性位点(fra)的表达与Ⅱ型糖尿病(NIDDM)的关系。实验组为10例老年NIDDM患者,年龄60~69岁,男4例,女6例,2例并发肾病,均有...  相似文献   
47.
Charged particle therapy utilizing protons or carbon ions has been rapidly intensifying over recent years. The present study was designed to jointly investigate these two charged particle treatment modalities with respect to modeled anatomical depth-dependent dose and linear energy transfer (LET) deliveries to cells with either normal or compromised DNA repair phenotypes. We compared cellular lethality in response to dose, LET and Bragg peak location for accelerated protons and carbon ions at 70 and 290?MeV/n, respectively. A novel experimental live cell irradiation OptiCell? in?vitro culture system using three different Chinese hamster ovary (CHO) cells as a mammalian model was conducted. A wild-type DNA repair-competent CHO cell line (CHO 10B2) was compared to two other CHO cell lines (51D1 and xrs5), each genetically deficient with respect to one of the two major DNA repair pathways (homologous recombination and non-homologous end joining pathways, respectively) following genotoxic insults. We found that wild-type and homologous recombination-deficient (Rad51D) cellular lethality was dependent on both the dose and LET of the carbon ions, whereas it was only dependent on dose for protons. The non-homologous end joining deficient cell line (Ku80 mutant) showed nearly identical dose-response profiles for both carbon ions and protons. Our results show that the increasingly used modality of carbon ions as charged particle therapy is advantageous to protons in a radiotherapeutic context, primarily for tumor cells proficient in non-homologous end joining DNA repair where cellular lethality is dependent not only on the dose as in the case of more common photon therapeutic modalities, but more importantly on the carbon ion LETs. Genetic characterization of patient tumors would be key to individualize and optimize the selection of radiation modality, clinical outcome and treatment cost.  相似文献   
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This paper highlights the most recent publications, in the field of psychiatry, on offspring of patients with psychiatric illnesses such as schizophrenia and bipolar disorder, and then summarizes what we know about the progeny of adults with mood disorders, the most prevalent of parental disorders. Studies examining personality disorders and contextual factors such as stress and trauma are examined with a focus on the crucial question of development and attachment status in children. Findings converge to reveal that offspring of parents (generally mothers) with most major psychiatric disorders present a higher risk for all mental disorders, and a wide range of disorders are also found in children, adolescent, and finally adult offspring of mothers with mood and anxiety disorders. Developmental psychopathology and infant and child psychiatry have focused on early relationship formation through social interaction and attachment patterns as pathways affected by vulnerability or resilience factors. First year of life longitudinal studies following mothers and infants has shown that maternal psychopathology is positively correlated with higher risk of attachment issues. It would seem that pathology appears when adaptation to real-life contexts becomes difficult in association with an accumulation of negative individual characteristics and environmental circumstances. We suggest that in order to move forward psychiatry should embrace a developmental cascade model, which posits a cumulative pathway for the emergence of psychopathology in the developing child. We propose that we have sufficient knowledge today to start implementing multilevel approaches to enhance the health and mental health of the next generation.  相似文献   
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