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Within the context of early diagnosis of Alzheimer's disease (AD), there is a growing interest in neuropsychological screening tests. Amongst these tests, we focused on the largely used Memory Impairment Screen (MIS). The objective of the present work was to show that adding a 10-min delayed recall to the MIS, improves the test psychometric characteristics in order to detect dementia in the earliest stages. A prospective study was carried out on a cohort of 270 consecutive elderly ambulatory subjects attending the Broca Hospital Memory Clinic: normal controls ( n  = 67), mild cognitive impairment subjects ( n  = 98) and mildly demented patients [ n  = 105, Mini Mental State Examination (MMSE) = 23 ± 4]. This study consisted in testing the advantage of the 10-min delayed recall entitled MIS-D compared with the MIS. At a cut-off score of 6, the MIS-D revealed satisfying psychometric characteristics with a sensitivity of 81% and a specificity of 91%, whilst the MIS alone indicated a sensitivity of 60% and a specificity of 88% in detecting dementia. In demented patients with MMSE score ≥26, MIS-D properties still remained satisfying (sensitivity: 75%, specificity: 92%). MIS-D is a more relevant screening test than MIS alone at very early stages of dementia.  相似文献   
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Background: Although the activation-induced intracellular Ca2+ signal is disrupted by sensory neuron injury, the contribution of specific Ca2+ channel subtypes is unknown.

Methods: Transients in dissociated rat dorsal root ganglion neurons were recorded using fura-2 microfluorometry. Neurons from control rats and from neuropathic animals after spinal nerve ligation were activated either by elevated bath K+ or by field stimulation. Transients were compared before and after application of selective blockers of voltage-activated Ca2+ channel subtypes.

Results: Transient amplitude and area were decreased by blockade of the L-type channel, particularly during sustained K+ stimulation. Significant contributions to the Ca2+ transient are attributable to the N-, P/Q-, and R-type channels, especially in small neurons. Results for T-type blockade varied widely between cells. After injury, transients lost sensitivity to N-type and R-type blockers in axotomized small neurons, whereas adjacent small neurons showed decreased responses to blockers of R-type channels. Axotomized large neurons were less sensitive to blockade of N- and P/Q-type channels. After injury, neurons adjacent to axotomy show decreased sensitivity of K+-induced transients to L-type blockade but increased sensitivity during field stimulation.  相似文献   

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The aim of this study was to characterize the binding and functional properties of muscarinic cholinergic (MCh) and alpha 2-adrenergic receptors in the human ileum to provide insight into pharmacologic strategies for managing urinary and fecal incontinence after bladder and rectal replacement with intestinal segments. MCh and alpha 2-adrenergic binding sites were characterized in the epithelium and muscularis of eight human ileal segments with 3H-N-methylscopolamine and 3H-rauwolscine, respectively. The dissociation constant for 3H-N-methylscopolamine in the epithelium and muscularis was 0.32 +/- 0.07 nmol/L and 0.45 +/- 0.10 nmol/L, respectively (p = 0.32). The MCh receptor content was approximately eightfold greater in the muscularis compared with the epithelium (p = 0.008). The dissociation constant for 3H-rauwolscine in the muscularis and epithelium was 2.55 +/- 0.42 nmol/L and 2.03 +/- 0.19 nmol/L, respectively (p = 0.29). The alpha 2-adrenoceptor density was twofold greater in the epithelium compared with the muscularis (p = 0.05). Noncumulative concentration-response experiments were performed with carbachol, an MCh agonist, and UK-14304, a selective alpha 2-adrenergic agonist. The epithelium did not contract in the presence of high concentrations of carbachol and UK-14304. The muscularis preparations were responsive only to carbachol. The muscularis contains primarily MCh receptors mediating smooth muscle contraction. The alpha 2-adrenoceptors are localized primarily to the epithelium and may regulate water secretion in the intestine. The distribution and functional properties of ileal MCh and alpha 2-adrenergic receptors provide a theoretic basis for the treatment of incontinence after bladder and rectal replacement with intestinal segments.  相似文献   
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Anorexia nervosa (AN) is often considered a multifactorial illness of unknown pathophysiology. Family and twin studies have consistently demonstrated that AN is strongly related to genetic factors. The probability of some genetic origin is 92%, genetic factors explaining around 20% of the variance. It must be remembered that 95% of the AN patients were girls or women, suggesting a role for gonadal hormonal systems and their effects on the brain and on cognitive functions. Most studies focused on the serotonin system, but other candidate genes have been suggested. At the present time, we have no evidence that women who develop AN have an adipose, metabolic, gonadal, pituitary, hypothalamic or some other dysfunctions that predispose them for the illness. It is suggested on the contrary that the symptoms of AN are physiological responses to starvation or to the response to altered body image and self-satisfaction. If this eating disorder is related to the fear of the alimentary desire of the patients, it will be easy to understand the plasma level of adiponectin, ghrelin and better understand a role for the low leptin level in the enhanced hunger. If we remember that almost 60% of these patients are engaged in a physical and mental hyperactivity, the abnormality in plasma level of cortisol, ACTH, and CRH. The decease in fat mass could explain why leptin level was low and low leptin level may explain the amenorrhea and the fall in LH, FSH, and LH–RH secretion. Moreover, anxiety, obsessive compulsive disorders and physical hyperactivity may be three interrelated factors, which could be related to serotonin and dopamine systems and in turn inhibit food intake.  相似文献   
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Transurethral resection of the prostate represents the operation most commonly performed by urologists in the United States. The objective of this study was to determine the efficacy of transurethral prostatectomy in men with moderate symptoms of prostatism. The efficacy parameters evaluated included peak urinary flow rate, obstructive and irritative symptom scores, and the global assessment by the patient of the voiding symptomatology. The mean peak urinary flow rate improved 108% after transurethral prostatectomy, and the mean obstructive and irritative symptom scores decreased 88 and 65%, respectively. The observed changes in urinary flow rates and symptom scores were statistically and clinically significant. Over-all, 84% of the patients indicated that the voiding symptoms were markedly improved after prostatic resection. Baseline urodynamic parameters were of no value for prediction of postoperative outcome. Several investigators recently reported their clinical experience with various pharmacological approaches for the treatment of symptomatic benign prostatic hyperplasia. Over-all, the degree of improvement in urinary flow rates and symptom scores achieved after transurethral prostatectomy exceeds all other therapeutic options that presently are available for the treatment of benign prostatic hyperplasia.  相似文献   
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