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81.
Patients with amyotrophic lateral sclerosis (ALS) have a motor disorder and cognitive difficulties, including difficulty with action verbs. However, the basis for the action verb impairment is unknown. Thirty-six participants with ALS and 22 with Parkinson’s disease (PD) were assessed on a simple, two-alternative forced-choice associativity judgment task, where performance was untimed and did not depend on motor functioning. We probed 120 frequency-matched action verbs, cognition verbs, concrete nouns and abstract nouns. Performance was related to T1 MRI imaging of gray matter atrophy. Patients with ALS were significantly impaired relative to healthy senior control participants only for action verbs. Patients with PD did not differ from controls for all word categories. Regression analyses related action verb performance in ALS to motor-associated cortices, but action verb judgments in PD were not related to cortical atrophy. These findings are consistent with the hypothesis that action verb difficulty in ALS is related in part to the degradation of action-related conceptual knowledge represented in motor-associated cortex.  相似文献   
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Background contextCombined monitoring of muscle motor evoked potentials elicited by transcranial electric stimulation (TES-mMEP) and cortical somatosensory evoked potentials (cSSEPs) is safe and effective for spinal cord monitoring during scoliosis surgery. However, TES-mMEP/cSSEP is not always feasible. Predictors of feasibility would help to plan the monitoring strategy.PurposeTo identify predictors of the feasibility of TES-mMEP/cSSEP during scoliosis surgery.Study design/settingProspective cohort study in a clinical neurophysiology unit and pediatric orthopedic department of a French university hospital.Patient sampleA total of 103 children aged 2 to 19 years scheduled for scoliosis surgery.Outcome measuresFeasibility rate of intraoperative TES-mMEP/cSSEP monitoring.MethodsAll patients underwent a preoperative neurological evaluation and preoperative mMEP and cSSEP recordings at both legs. For each factor associated with feasibility, we computed sensitivity, specificity, positive predictive value (PPV), and negative predictive value. A decision tree was designed.ResultsPresence of any of the following factors was associated with 100% feasibility, 100% specificity, and 100% PPV: idiopathic scoliosis, normal preoperative neurological findings, and normal preoperative mMEP and cSSEP recordings. Feasibility was 0% in the eight patients with no recordable mMEPs or cSSEPs during preoperative testing. A decision tree involving three screening steps can be used to identify patients in whom intraoperative TES-mMEP/cSSEP is feasible.ConclusionsPreoperative neurological and neurophysiological assessments are helpful for identifying patients who can be successfully monitored by TES-mMEP/cSSEP during scoliosis surgery.  相似文献   
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OBJECTIVES: The aim of this study was to test whether peroxynitrite neutralizers would reduce peroxynitrite accumulation and improve myocardial contractile dysfunction and inflammation in endotoxin-treated rats. BACKGROUND: Release of endogenous proinflammatory cytokines such as tumor necrosis factor (TNF)-alpha in response to endotoxin is responsible for the production of large amounts of nitric oxide (NO), which may exert detrimental effects on the myocardium in animal models, isolated hearts, and isolated cardiac myocytes. Recent studies have indicated that many of the deleterious effects of NO are mediated by peroxynitrite, a powerful oxidant generated from a fast diffusion-limited reaction of NO and superoxide anion. METHODS: We studied the effects of peroxynitrite neutralizers, such as mercaptoethylguanidine (MEG) sodium succinate (10 mg/kg) and 5,10,15,20-tetrakis(4-sulfonatophenyl)-porphyrinato iron (III) (FeTPPS) (30 mg/kg) on peroxynitrite accumulation, in vivo endothelial cell-leukocyte activation on the mesenteric venule, and myocardial contractile dysfunction and inflammation in a model of sepsis induced by injection of endotoxin (10 mg/kg) in rats. RESULTS: Mercaptoethylguanidine sodium succinate and FeTPPS largely prevented the accumulation of peroxynitrite as measured by plasma rhodamine fluorescence and heart nitrotyrosine staining. Interestingly, MEG sodium succinate and FeTPPS improved endotoxin-induced myocardial contractile dysfunction, which was associated with reduced degradation of nuclear factor kappa B inhibitory protein I-kappa-B, plasma TNF-alpha levels, and microvascular endothelial cell-leukocyte activation. CONCLUSIONS: These observations suggest that the beneficial effects of MEG and FeTPPS on endotoxin-induced myocardial contractile dysfunction could be related to the unique effects of these compounds on cardiovascular inflammation processes.  相似文献   
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BACKGROUND: Coeliac women may suffer from gynaecological and obstetric complications. It is possible that these complications are the first symptom of coeliac disease. AIMS: To investigate the occurrence of subclinical coeliac disease in patients with infertility or recurrent miscarriages. SUBJECTS: Women of reproductive age who were attending the hospital because of either primary or secondary infertility, or two or more miscarriages. Women undergoing sterilisation served as control subjects. METHODS: The diagnostic investigation for infertility included the endocrine status, diagnostic laparoscopy, investigation of tubal patency, postcoital test, and semen analysis of the partner. Circulating antibodies against IgA class reticulin and gliadin were used in screening for coeliac disease. In positive cases, the diagnosis was confirmed by small bowel biopsy specimens. RESULTS: Four (2.7%) of 150 women in the infertility group, and none of the 150 control subjects were found to have coeliac disease (p = 0.06). All four women with coeliac disease suffered from infertility of unexplained origin. Altogether 98 women had no discoverable reason for infertility. Thus, in this subgroup the frequency of coeliac disease was 4.1% (four of 98), the difference from the control group being statistically significant (p = 0.02). None of the coeliac women had extensive malabsorption, but two had iron deficiency anaemia. One women with coeliac disease has had a normal delivery. None of the 50 women with miscarriage had coeliac disease. CONCLUSION: Patients having fertility problems may have subclinical coeliac disease, which can be detected by serological screening tests. Silent coeliac disease should be considered in the case of women with unexplained infertility.  相似文献   
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Forensic Toxicology - In developed countries, lead intoxication is decreasing in adults as sources of contamination were considerably reduced. Hence, cases of lead encephalopathy have become...  相似文献   
89.

Purpose

Despite providing adequate pain relief, a femoral nerve block can induce postoperative muscle weakness after total knee arthoplasty (TKA). Fentanyl has been shown to have peripheral effects but has not been used as a perineural infusate alone after TKA.

Methods

Sixty patients scheduled for TKA were randomized to one of three blinded groups: a continuous 24 h infusion of either fentanyl 3 μg/ml, ropivacaine 0.1 %, or 0.9 % normal saline through a femoral nerve sheath catheter at 10 ml/h. The main outcome was maximum voluntary isometric contraction (MVIC) in the quadriceps femoris (knee extension), measured by a handheld dynamometer (Nm/kg). Other variables assessed were preoperative and postoperative visual analog scale (VAS) scores, hamstrings MVIC (knee flexion), active range of motion of the operative knee, distance ambulated, incidence of knee buckling, supplemental morphine usage, postoperative side effects, and serum fentanyl levels.

Results

Quadriceps MVIC values were significantly greater in the fentanyl group compared to the group that received ropivacaine (median values, 0.08 vs. 0.03 Nm/kg; p = 0.028). The incidence of postoperative knee buckling upon ambulation was higher in the ropivacaine group compared to the fentanyl group, although not statistically significant (40 % vs. 15 %, respectively; p = 0.077). VAS scores while ambulating were not significantly different between the fentanyl group and the ropivacaine group (p = 0.270). Postoperative morphine consumption, nausea and vomiting, and resting VAS scores were similar among the three groups.

Conclusions

A continuous perineural infusion of fentanyl produced greater strength retention than ropivacaine post-TKA.  相似文献   
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