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101.
Visual spatial attention to stimuli presented on the vertical and horizontal meridian: An ERP study 总被引:6,自引:0,他引:6
THOMAS C. GUNTER ALBERTUS A. WIJERS JANET L. JACKSON GIJSBERTUS MULDER 《Psychophysiology》1994,31(2):140-153
In the first experiment, 48 subjects carried out a visual spatial attention task. Stimuli were presented at the vertical meridian, either above or below a fixation dot, and the subjects were instructed to attend to one of these stimulus positions and ignore the other position. In three different conditions, the distances between stimulus positions and fixation were 0.5°, 0.9°, and 1.3°. Subjects searched for the presence of prememorized target letters at the attended location: memory load was one or four items in different conditions. The P1/N1 enhancement typically found on the horizontal dimension was not observed on the vertical dimension. Instead, a positive shift of the attended compared with the unattended stimuli was found, which was most prominent at anterior electrodes. This positivity showed effects of the distance manipulation. The N2b-P3a effect of attention and the effect of memory load (search negativity) normally present in this kind of selective search task were also found. Reaction times were faster when attention was directed above fixation than when it was directed below fixation. The event-related potential data suggested that this difference could be attributed to a more efficient neglecting of irrelevant stimuli presented below fixation. In Experiment 2, we examined whether the absence of the P1/N1 enhancement as the result of spatial attention in Experiment 1 could be attributed to (a) the presentation of stimuli along the vertical meridian instead of along the horizontal meridian, (b) the use of midline electrodes instead of lateralized electrodes, and (c) the relatively small spatial separation between the relevant and irrelevant stimuli. Twelve subjects searched for the presence of a single target letter at an attended position in three different conditions. In two of the conditions the letters were presented to the left or right of fixation. The distance between fixation and the stimulus positions was 1.3° in one of these conditions and 3° in the other condition. In the third condition, the stimuli were presented at 3° above or below fixation. In all three conditions effects similar to those in Experiment 1 were observed. In addition, in all three conditions an enhancement of the P1 and N1 components was found at two lateral occipitotemporal electrodes. 相似文献
102.
目的:探讨单发性和多发性浅表膀胱移行细胞癌组织中血管内皮生长因子(VEGF)的表达及意义。方法:采用免疫组化方法对60例浅表膀胱移行细胞癌组织及10例正常膀胱组织进行血管内皮生长因子(VEGF)的检测,观察单发性和多发性浅表膀胱移行细胞癌组织中VEGF表达的关系。结果:多发性浅表膀胱移行细胞癌VEGF的高表达明显高于单发者的高表达;VEGF高表达的浅表膀胱移行细胞癌的患者的复发率明显高于低表达者的复发率。结论:VEGF表达的高低与浅表膀胱移行细胞癌的生物学行为有关。 相似文献
103.
David W. Ingersoll George Bobotas Ching-Tse Lee Aaron Lukton 《Physiology & behavior》1982,29(5):789-793
The present study was designed to investigate the chemical properties of the aggression-promoting cues present in bladder urine of male mice. The results of the first experiment confirmed earlier work by demonstrating the presence of an aggression-promoting chemosignal in bladder urine. In Experiment 2, behavioral assays were separately performed on the organic and aqueous layers of bladder urine obtained by repeated dichloromethane extractions. Only the combined organic layers of the initial three extractions demonstrated behavioral activity. A fourth extraction showed no behavioral activity for both organic and aqueous layers. However, the findings of Experiment 3 showed that incubation of the aqueous layer from the third CH2Cl2 extraction in β-glucuronidase can free additional aggression-promoting cues into a subsequent CH2Cl2 extraction. It is concluded that two forms of the aggression-promoting chemosignal are present in bladder urine. One is lipophilic and behaviorally active, whereas the other is conjugated, possessing latent chemosignal properties. 相似文献
104.
105.
R. C. P. Lima-Júnior D. I. M. Sousa G. A. C. Brito G. M. Cunha M. H. Chaves V. S. N. Rao F. A. Santos 《Inflammation research》2007,56(12):487-494
Objective and design: We previously described the visceral antinociceptive property of α, β-amyrin in a mouse model of cystitis induced by cyclophosphamide
(CPM). This study examined the contribution of vanilloid-1 (TRPV1), peripheral NK1 receptors to CPM-evoked nociceptive behaviors
and bladder edema, and its possible modulation by α, β-amyrin.
Methods: The effect of α, β-amyrin (10, 30, and 100 mg/kg, p. o.) and N-acetylcysteine (NAC) on CPM (400 mg/kg, i. p.)-induced cystitis
was studied in mice. Sensory deafferentation was done by a high dose capsaicin. The parameters analysed were: CPM-evoked noxious
behaviors, bladder edema, vascular permeability, and NK1 immunoreactivity. To assess the role of K+
ATP channels in α, β-amyrin effect, animals were pretreated with glibenclamide.
Results: α, β-amyrin (30 and 100 mg/kg) and NAC significantly (p < 0.01) suppressed the visceral pain-related behaviors and NK1 immunoreactivity, but bladder edema was reduced weakly. Glibenclamide reversed the effects of α, β-amyrin. Sensory deafferentation
by capsaicin significantly reduced the nociceptive responses and the NK1 immunoreactivity to noxious stimulation by CPM.
Conclusions: α, β-amyrin attenuates CPM-induced visceral pain and bladder edema by mechanisms that involve, at least in part, a block either
of Substance P release or its receptor function, and partly by opening K+
ATP channels.
Received 13 February 2007; returned for revision 13 April 2007; accepted by G. Geisslinger 14 May 2007 相似文献
106.
D. Kirsten U. Rieger K. H. Schröder A. Böhle H. Magnussen 《Journal of molecular medicine (Berlin, Germany)》1993,71(10):787-790
Summary Immunotherapy using bacille Calmette-Guérin (BCG) has gained increasing acceptance in the management of superficial bladder cancer. Systemic reactions after intravesical instillation of BCG are rare. However, when the therapy is complicated, the lung often becomes involved. Since the pathogenesis of lung infiltrates after immunotherapy is unknown, we report on a patient who developed a lung infiltrate after receiving BCG immunotherapy for bladder cancer. The infectious etiology was established by culture confirmation of a BCG strain in the broncheoalveolar lavage fluid.Abbreviation BCG
bacille Calmette-Guérin 相似文献
107.
人皮肤内神经-肥大细胞联接在经络线上的发现 Ⅱ“传入性”神经-肥大细胞联接和伴同传出性轴突的薛旺细胞 总被引:2,自引:0,他引:2
本研究取材于人的皮肤,电镜常规方法处理。发现人皮肤内有两种类型的神经肥大细胞联接。提示可能分别为传出性和传入性的,或暂称为A型和B型联接,分别报告于上篇和本篇中。 B型联接的构造特点是,脱开薛旺鞘样长带包被的轴突来到肥大细胞近旁,突进细胞体中。轴突终末的一部分被胞质唇封盖起来,终末周围的轴膜与细胞质膜形成联接的双层膜。无肥大细胞表面皱褶参与其形成,无线粒体和显明的囊泡存在终末之内,无薛旺细胞包被轴突终末。薛旺细胞伴同A型联接出现,可与肥大细胞紧密接触。胞质内有狭缝系统和粗面内质网片断,能拖出长尾,估计将过渡为鞘膜。薛旺细胞不是间织细胞,这里的间织细胞应是成纤维细胞。 相似文献
108.
The relationship between bladder cancer and alcohol consumption was investigated in a case-control study conducted in 546 patients (453 males and 53 females) with diagnoses of papillary urothelial carcinoma during 1978–1982 at La Paz hospital (Madrid), and an equal number of controls matched for age, sex and date of admission to the hospital. The results showed that the risk of bladder cancer does not increase with the intake of beer, wine and spirit beverages. However, a high risk of bladder cancer was associated with consumption of wine mixed with gaseosa (a refreshment beverage consisiting of carbonated water plus artificial sweeteners). 相似文献
109.
Paolo Santicioli Rainer Gamse Carlo Alberto Maggi Alberto Meli 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(5):580-587
Summary 1. The effect of streptozotocin (STZ) induced diabetes on rat urinary bladder function was investigated by means of in vivo cystometry and in vitro recording of bladder strips contractility. A group of sucrose-fed animals was included to determine to what extent the STZ-induced changes were ascribable to the increased diuresis. 2. After 7–9 weeks from STZ injection there was a marked increase in weight of bladder and ureters. Cystometry revealed a marked increase in bladder capacity (volume threshold) although pressure threshold and amplitude of micturition contraction were unaffected. Sucrose-fed animals, having normal blood glucose levels but a similar increase in urine production exhibited cystometric changes identical to those of STZ animals. 3. In vitro experiments indicated that the response to field stimulation (0.1–20 Hz) is reduced in STZ-pretreated but increased in sucrose-fed animals, as compared to controls. 4. The content of urinary bladder and ureters in sensory neuropeptides (substance-P, neurokinin-A and calcitonin-gene related peptide-like immunoreactivity) was increased by STZ diabetes when values were corrected for the increased weight of these organs. 5. The capsaicin-induced contraction of the rat isolated bladder strips, presumably caused by neuropeptides released from intramural sensory nerves, is unaffected by STZ diabetes. 6. These findings indicate that STZ diabetes produces, at an early stage, changes similar to those reported to occur in the human disease, e. g. a greater bladder capacity with unimpaired voiding function. The increased bladder capacity of STZ-rats seems largely, if not solely, ascribable to changes in physical properties of the detrusor muscle, thereby allowing accomodation of greater than normal volumes with similar increase of intraluminal pressure. No sign of diabetic neuropathy of the capsaicin-sensitive sensory nerves can be observed at this stage (7–9 weeks) of STZ diabetes.
Send offprint requests to P. Santicioli at the above address 相似文献
110.
目的 探讨性激素在膀胱癌发病中的意义。方法 :采用放射免疫法检测 31例男性膀胱癌患者及 2 7例同年龄正常人对照组血清中的雌二醇 (EstradiolE2 )、孕酮 (ProgesteroneP)及睾酮 (TestosteroneT)水平。结果 :男性膀胱癌患者血清E2 、P、T分别为 44.98± 2 0 .96pg ml( x±s) ,0 .37± 0 .18ng ml( x±s) ,6 .2 5± 2 .37ng ml( x±s) ,而正常对照组E2 、P、T分别为 5 6 .0 1± 13.5 0pg ml( x±s) ,1.14± 0 .37ng ml( x±s) ,5 .15± 1.37ng ml( x±s) ,两者比较膀胱癌组T明显高于对照组 (P <0 .0 5 ) ;而E2 、P明显低于对照组 (P <0 .0 5 )。结论 :膀胱癌的发生可能与性激素代谢失衡有一定的关系 相似文献