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D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
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Cholinergic septal grafts into the hippocampal formation improve spatial learning and memory in aged rats by an atropine-sensitive mechanism 总被引:4,自引:0,他引:4
Behaviorally impaired old rats were selected from a population of 75 21- to 23-month-old rats on the basis of the place-investigated abilities in the Morris' water-maze task. After the pretransplant test, half of the old impaired rats received bilateral intrahippocampal cell suspension grafts prepared from the fetal septal-diagonal band region, which is rich in developing cholinergic neurons; the other half were left as sham-operated controls. Twelve weeks after grafting, the rats were retested in the water-maze using alternating cue-navigation and place-navigation trials (i.e., with visible or nonvisible escape platform). While the old impaired controls had deteriorated further between the 2 tests and showed poor retention of the pretransplant performance level, the grafted rats were significantly improved in comparison with both their pretransplant performance and the performance of the old impaired controls in the posttransplant test. The graft-induced effect was due both to an improved retention of the performance level acquired in the test performed prior to transplantation surgery, and to an improved acquisition of spatial memory of the escape platform site during the posttransplant test week (measured as an improved focusing of search over the platform site after platform removal). The acetylcholine esterase inhibitor physostigmine had no or only marginal effects on the performance of any of the young or aged rat groups. By contrast, the recovered navigational abilities and spatial memory in the grafted animals were completely abolished after administration of the muscarinic receptor antagonist atropine. A similar atropine-sensitivity was seen in behaviorally nonimpaired aged rats but not in the well-trained young control rats. The results show that cholinergic septal grafts, implanted into the hippocampal formation, improved spatial learning in the impaired aged rats primarily, or perhaps exclusively, by a recovery of the rats' ability to use spatial cues for place-navigation in the water-maze, while other aspects of the performance deficits in the water-maze task in the aged rats were left unaffected by the septal grafts. On the basis of parallel morphological studies, it is proposed that the effects of the septal grafts on the spatial learning impairments in the aged rats are critically dependent on the direct action of cholinergic neurons in the grafts via synapses formed onto neuronal elements in the host by their ingrowing axons. 相似文献
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R B Gage 《The Nurse practitioner》1991,16(4):11-16
Spouse abuse continues to be a great problem in our society. Much of the literature about the problem, however, assumes that the roles of perpetrator and victim are always fixed, with the man as perpetrator and the woman as victim. This perception is understandable if the injuries received are the focus of attention, and the sole informant about the violence is the person who has most often been the recipient of injuries. On occasions when both partners are interviewed, a different perception of violent relationships is likely to emerge. Violence can be viewed as occurring along a continuum. One extreme is represented as mutual combat, in which both partners play a role in the escalation of conflict. The other extreme follows the traditional concept of battering where the woman is victimized by the man. Primary care practitioners are in a position to assist clients who are in violent relationships and to help them learn more functional problem-solving skills. This article focuses on methods of identifying violent couples and teaching them how to interrupt the cycle of violence. 相似文献
6.
V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
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E Schmidt-Sommerfeld D Penn P Rinaldo D Kossak B U Li Z H Huang D A Gage 《Pediatric research》1992,31(6):545-551
To determine the sensitivity and specificity of detecting urinary medium-chain acylcarnitines for the diagnosis of MCAD deficiency, 114 urine specimens from 75 children with metabolic diseases and controls were analyzed in a blinded fashion using a radioisotopic exchange/HPLC method. All 47 patients with MCAD deficiency were correctly diagnosed using the criterion hexanoylcarnitine or octanoylcarnitine peak areas larger than those of other medium-chain acylcarnitines. The majority of them were tested during the asymptomatic state without L-carnitine loading. Four patients with other defects of fatty acid oxidation and three patients receiving valproic acid had a similar acylcarnitine excretion pattern. To further examine the specificity of the method, eight infants receiving a diet enriched with medium-chain triglycerides and 13 additional patients receiving valproic acid were studied. Most of these also tested positive for MCAD deficiency by the above criterion. Analysis by a new gas chromatographic-mass spectrometric procedure revealed that octanoylcarnitine, not valproylcarnitine, was the most abundant medium-chain carnitine ester excreted by a patient treated with valproic acid. Quantitation of urinary hexanoylcarnitine and octanoylcarnitine showed considerable overlap among patients with MCAD deficiency and those receiving valproic acid or a medium-chain triglyceride-enriched diet. MCAD deficiency can be reliably detected in urine specimens by this method without the need for prior carnitine loading. However, other defects in fatty acid oxidation must be differentiated from MCAD deficiency, and a history of medium-chain triglyceride or valproic acid administration must be considered if the diagnosis of MCAD deficiency is sought through analysis of urinary acylcarnitines. 相似文献
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1. The amplitude of endplate potentials was increased by concentrations of butanedione monoxime (BDM, 5-20 mM) that typically caused muscle paralysis. 2. Although BDM slowed the decay of spontaneous miniature endplate currents, the effect was insufficient to explain most of the large increase in amplitude of endplate potentials. 3. The quantal content of endplate potentials was increased by BDM in a reversible, concentration-dependent manner. 4. The frequency of miniature endplate potentials was not changed by 10 mM BDM in the presence of normal or raised potassium concentrations, indicating that BDM does not change quantal content by a direct effect on calcium channels or on steady-state intracellular calcium concentration. 5. A change in the time course of the extracellularly recorded nerve terminal action potential caused by BDM was similar to the change produced by 4-aminopyridine (4-AP). 6. The increase in quantal content produced by BDM was only slightly reduced in the presence of 1 mM tetraethylammonium (TEA) but was significantly reduced in the presence of 0.5 to 1 mM 4-AP. 7. It was concluded that BDM blocks a 4-AP-sensitive potassium conductance in motor nerve terminals and, by increasing the duration of the action potential in this way, increases evoked transmitter release. 相似文献