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Objectives. This study investigates an overall autonomic hypoactivity reflecting hypoarousal as important aetiological factor in ADHD at baseline during rest and in response towards stimuli. In addition, effects of methylphenidate (MPH) are examined. We further assessed whether this hypoarousal is a stable characteristic or ameliorated by arousing emotional stimuli. Methods. Boys with ADHD were examined with (n = 35) or without MPH (n = 45) and compared with healthy boys (n = 22) regarding skin conductance level (SCL) during rest and skin conductance responses (SCRs) as well as valence and arousal ratings in response to positive, neutral, and negative pictures. Results. ADHD children without MPH were characterized by reduced baseline SCL and overall reduced SCRs. ADHD children with MPH never differed from control children. All groups displayed normal valence and arousal ratings of the stimuli and enhanced SCRs to emotional in comparison to neutral pictures. Conclusions. This is the first study to unravel (1) a general autonomic hypoactivity in ADHD children at baseline and in response to low arousing neutral and highly arousing emotional stimuli, and (2) hints that MPH normalizes this hypoactivity. Results contribute to the understanding of ADHD aetiology and MPH functionality, and are consistent with the cognitive-energetic model of ADHD.  相似文献   
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Monatsschrift Kinderheilkunde - Eine adäquate Energie- und Nährstoffversorgung ist Grundlage für ein gesundes Wachstum und Voraussetzung für die Erhaltung von Gesundheit und...  相似文献   
24.
Vestibular dysfunction was chemically induced in male meadow voles (Microtus pennsylvanicus) by intratympanic injections (30 mg per side) of sodium arsanilate (atoxyl). The control group received intratympanic injections of isotonic saline. After a one-week recovery period the voles were behaviorally assayed for integrity of their labyrinthine systems. All subjects were tested for the presence of the air-righting reflex and body rotation-induced nystagmus. Three weeks later a multivariate assessment of spontaneous motor activity of the voles was carried out in the automated Digiscan Activity Monitor. In addition, the swimming behavior of the voles was examined. Voles with vestibular dysfunction exhibited pronounced postural abnormalities (head dorsiflexion), were not able to swim with their nose above the water for a 1 min test period, and displayed disorientation and thrashing movements. In the Digiscan activity test the atoxyl-treated voles displayed significantly more activity in the horizontal measures (Ps less than 0.01), including greater distance travelled per movement and greater speed of movements, relative to the control animals. The labyrinthectomized group also spent significantly (P less than 0.05) less time in vertical movements and exhibited significantly more time in stereotypic behavior (P less than 0.01), relative to controls. Atoxyl-treated voles also showed significantly less thigmotaxis (wall-hugging) than the control animals (P less than 0.01). In general, changes in spontaneous behavior observed in the sodium arsanilate-treated voles were consistent with the presence of postural and balance abnormalities and a redirecting of exploratory vertical movements toward horizontal locomotion to the extent that these animals were clearly hyperactive in this dimension. The multivariate behavioral assessment available in the Digiscan Activity Monitoring system, thus seems to be especially useful in the examination of behavioral components affected by vestibular dysfunction.  相似文献   
25.
The aim of the study was to isolate from the clinical history and examination, symptoms, or combination of symptoms highly suspicious for intestinal infiltration in endometriosis patients. In a prospective study, preoperative anamnesis on defecation problems and pain symptoms was correlated with the vaginal examination and the laparoscopic findings in 2,000 consecutive patients with suspicion of intestinal endometriosis; 65.7% of the patients reported a typical symptomatology combining left-sided pelvic pain irradiating systematically to the back and occasionally to the left leg, with dyschesia, abdominal bloating, and/or sensation of a doubt masse in the left lower or middle abdomen, sometimes rectorrhagia and an improvement in the pain after defecation. In the absence of a palpable endometriotic nodule of the rectovaginal space, the combination of this symptoms correlated in 93.7% of the patients with an outlet constipation syndrome due to a significant elongation with kinking of the rectosigmoide. In the patients with a palpable endometriotic nodule of the posterior fornix (n = 712), the combination of an apareunia with the apparition of constipation for 2–3 days at the beginning of the period bleeding followed by a diarrhea until the end of the period shows a positive predictive value for deep intestinal infiltration of 95%. In all endometriosis patients undergoing a laparoscopy for pain and intestinal disorders, the elongation of the rectosigmoide must be perceived and recognized as a potential cause for an outlet constipation syndrome which can be cured easily by a left-sided sigmoidopexy. In patients with a macroscopic endometriotic nodule of the posterior fornix, the presence of an apareunia and the apparition of constipation at the beginning of the menstruation followed 2–3 days later by a diarrhea are strong arguments for an invasive intestinal endometriosis, and those patients must be primarily referred to a tertiary referral center. No financial support was received for this study.  相似文献   
26.
PURPOSE: Somatostatin receptor (sst) targeting is an established method to image and treat sst-positive tumors. Particularly, neuroendocrine tumors express the receptor subtype 2 in high density, but sst1, sst3, sst4, and sst5 are also expressed to some extent in different human tumors. Currently used targeting peptides mainly have sst2 affinity. We aimed at developing (radio)peptides that bind with high affinity to all receptor subtypes. EXPERIMENTAL DESIGN: Carbocyclic octapeptides were coupled with macrocyclic chelators for radiometal labeling. Affinity, internalization, and agonist potencies were determined on sst1- to sst5-expressing cell lines. Biodistribution was determined on nude mice bearing HEK-sst2 or AR4-2J and HEK-sst3 tumors. RESULTS: High affinity to all receptor subtypes was found. Y(III)-KE88 showed agonistic properties at all five sst receptor subtypes as it inhibits forskolin-stimulated cyclic AMP production. Surprisingly, very low or even absent sst2 receptor internalization was found compared with currently clinically established octapeptides, whereas the sst3 internalization was very efficient. Biodistribution studies of [(111)In]KE88 and [(67)Ga]KE88/[(68)Ga]KE88 reflected the in vitro data. In nude mice with s.c. implanted sst2 (HEK-sst2, AR4-2J)-expressing and sst3 (HEK-sst3)-expressing tumors, high and persistent uptake was found in sst3-expressing tumors, whereas the uptake in the sst2-expressing tumors was lower and showed fast washout. The kidney uptake was high but blockable by coinjection of lysine. CONCLUSION: This peptide family shows pansomatostatin potency. As radiopeptides, they are the first to show a full pansomatostatin profile. Despite some drawback, they should be useful for imaging sst2-expressing tumors with short-lived radiometals, such as (68)Ga, at early time points and for sst3-expressing tumors at later time points with longer-lived radiometals, such as (64)Cu or (86)Y.  相似文献   
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28.
Three new pyrone glucosidic derivatives, together with the known pyromeconic acid glucoside, three acytelenes and two eudesmanes, were obtained from the aerial parts of Conyza albida. The structures were elucidated by high field NMR spectroscopy.  相似文献   
29.
Role of taurine accumulation in keratinocyte hydration   总被引:2,自引:0,他引:2  
Epidermal keratinocytes are exposed to a low water concentration at the stratum corneum-stratum granulosum interface. When epithelial tissues are osmotically perturbed, cellular protection and cell volume regulation is mediated by accumulation of organic osmolytes such as taurine. Previous studies reported the presence of taurine in the epidermis of several animal species. Therefore, we analyzed human skin for the presence of the taurine transporter (TAUT) and studied the accumulation of taurine as one potential mechanism protecting epidermal keratinocytes from dehydration. According to our results, TAUT is expressed as a 69 kDa protein in human epidermis but not in the dermis. For the epidermis a gradient was evident with maximal levels of TAUT in the outermost granular keratinocyte layer and lower levels in the stratum spinosum. No TAUT was found in the basal layer or in the stratum corneum. Keratinocyte accumulation of taurine was induced by experimental induction of skin dryness via application of silica gel to human skin. Cultured human keratinocytes accumulated taurine in a concentration- and osmolarity-dependent manner. TAUT mRNA levels were increased after exposure of human keratinocytes to hyperosmotic culture medium, indicating osmosensitive TAUT mRNA expression as part of the adaptation of keratinocytes to hyperosmotic stress. Keratinocyte uptake of taurine was inhibited by beta-alanine but not by other osmolytes such as betaine, inositol, or sorbitol. Accumulation of taurine protected cultured human keratinocytes from both osmotically induced and ultraviolet-induced apoptosis. Our data indicate that taurine is an important epidermal osmolyte required to maintain keratinocyte hydration in a dry environment.  相似文献   
30.
Kinner BJ  Best R  Falk K  Thon KP 《The Journal of trauma》2002,53(6):1094-101; discussion 1102
BACKGROUND: The treatment of displaced intra-articular calcaneal fractures remains controversial, because of difficulties in assessing the outcome. The goal of this study, therefore, was to compare different outcome measurements with gait analysis, using dynamic pedography. METHODS: Twenty patients with operatively treated displaced intra-articular calcaneal fractures were followed up clinically and radiographically. In addition, foot pressure was measured using dynamic pedography. RESULTS: No significant difference was found between the two clinical outcome scores used (p = 0.08); both revealed good results. Dynamic pedography, however, showed a shift of the maximum impact and roll-off of the foot to the lateral side, as well as a widening of these zones in the heel and on the sole in 14 of 20 patients. CONCLUSION: These results indicate that traditional outcome measurements underestimate functional deficits in our patients. Monitoring plantar pressure distribution might therefore be a useful tool for assessing foot function in these patients.  相似文献   
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