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61.
Summary.  In this work we present evidence that the homologous peptides IHSMNSTIL and IHSMNSSIL derived from L1 HPV-16 and 18 proteins respectively, and with high specificity for the allele HLA-B*3901, according with an algorithm prediction program, induced T cell stimulation in patients with advanced cervical cancer positive for HPV-16 or 18 infection and for the HLA-B*3901 allele. Interestingly, T lymphocytes derived from a patient with HPV-18 infection and stimulated with the peptide IHSMNSTIL were capable to kill a cervical cancer cell line named Rova, derived from the tumor of the same patient. In addition, the cytotoxic activity was strongly increased when this cell line was previously treated with hrIFN-γ. These results suggest that the CTL immune response to L1 HPV-16 and 18 protein derived epitopes is maintained in patients with advanced cervical cancer within specific alleles, and opens the possibility that homologous epitopes may be used in the generation of prophylactic vaccines for cervical tumors bearing different HPV-types. Received March 4, 2002; accepted May 20, 2002  相似文献   
62.
Variation in response latency to identical sensory stimuli has been attributed to variation in neural activity mediating preparatory set. Here we report evidence for a relationship between saccadic reaction time (SRT) and set-related brain activity measured with event-related functional magnetic resonance imaging. We measured hemodynamic activation time-courses during a preparatory "gap" period, during which no visual stimulus was present and no saccades were made. The subjects merely anticipated appearance of the target. Saccade direction and latency were recorded during scanning, and trials were sorted according to SRT. Both the frontal (FEF) and supplementary eye fields showed pre-target preparatory activity, but only in the FEF was this activity correlated with SRT. Activation in the intraparietal sulcus did not show any preparatory activity. These data provide evidence that the human FEF plays a central role in saccade initiation; pre-target activity in this region predicts both the type of eye movement (whether the subject will look toward or away from the target) and when a future saccade will occur.  相似文献   
63.
难治性便秘综合治疗及影响因素的评价   总被引:1,自引:0,他引:1  
目的评价综合治疗对难治性便秘的疗效及影响因素。方法将84例难治性便秘分为非重叠组和重叠组。应用个体化综合治疗4周,观察便秘症状评分变化及总有效率,分析IC患者的重叠症状和心理障碍状态对疗效的影响。结果(1)84例便秘患者中,重叠组和非重叠组分别占40.5%和59.5%。(2)重叠组和非重叠组的总有效率分别为50.0%和78.0%(P<0.05)。(3)对37例IC患者的心理测试调查显示,59.4%(22/37)有心理障碍状态,重叠组和非重叠组伴有心理障碍状态对治疗的总有效率分别为4.8%和31.5%(P<0.05)。结论适合个体化的综合治疗使多数难治性便秘缓解症状,但伴有重叠症状,尤其心理障碍状态则影响疗效。  相似文献   
64.
65.
Neuropathological diagnostic criteria for Creutzfeldt-Jakob disease (CJD) and other human transmissible spongiform encephalopathies (prion diseases) are proposed for the following disease entities: CJD - sporadic, iatrogenic (recognised risk) or familial (same disease in 1st degree relative): spongiform encephalopathy in cerebral and/or cerebellar cortex and/or subcortical grey matter; or encephalopathy with prion protein (PrP) immuno-reactivity (plaque and/or diffuse synaptic and/or patchy/perivacuolar types). Gerstmann-Sträussler-Scheinker disease (GSS) (in family with dominantly inherited progressive ataxia and/or dementia): encephalo(myelo)pathy with multicentric PrP plaques. Familial fatal insomnia (FFI) (in member of a family with PRNP178 mutation): thalamic degeneration, variable spongiform change in cerebrum. Kuru (in the Fore population). Without PrP data, the crucial feature is the spongiform change accompanied by neuronal loss and gliosis. This spongiform change is characterised by diffuse or focally clustered small round or oval vacuoles in the neuropil of the deep cortical layers, cerebellar cortex or subcortical grey matter, which might become confluent. Spongiform change should not be confused with non-specific spon-giosis. This includes status spongiosus (“spongiform state”), comprising irregular cavities in gliotic neuropil following extensive neuronal loss (including also lesions of “burnt-out” CJD), “spongy” changes in brain oedema and metabolic encephalopathies, and artefacts such as superficial cortical, perineuronal, or perivascular vacuolation; focal changes indistinguishable from spongiform change may occur in some cases of Alzheimer's and diffuse Lewy body diseases. Very rare cases might not be diagnosed by these criteria. Then confirmation must be sought by additional techniques such as PrP immunoblotting, preparations for electron microscopic examination of scrapie associated fibrils (SAF), molecular biologic studies, or experimental transmission.  相似文献   
66.
Summary Afferent single fiber impulses were recorded from isolated ampullae of Lorenzini of dogfishes (Scyliorhinus canicula). The ampullae were placed between two thermodes, each of which could be circulated separately with water at 12°, 18° and 24° C, thus allowing cooling and warming with various combinations of spatial temperature gradients. At constant temperature, there was a static discharge in the ampullary fibers. Cooling elicited a dynamic overshoot in frequency, followed by adaptation to a new steady state, whereas warming led to a transient inhibition. Within the limits of error the direction and slope of the spatial temperature gradient had no influence whatsoever on the static and dynamic responses of the ampullae, the only effective parameters being the temperature at the site of the receptor and the rate of temperature change with time.About 13% of the single fibers responded with bursts of impulses, interrupted by silent intervals, and 10% showed an inversed dynamic response, i.e. dynamic overshoot on warming and transient inhibition on cooling. It is possible that these patterns of activity are anomalous responses.This work was supported by the Deutsche Forschungsgemeinschaft.  相似文献   
67.
68.
This report describes a family with mental retardation in two brothers. The pedigree is consistent with either X-linked mental retardation or autosomal recessive inheritance. The clinical features consist of coarse face, prominent lower lip, large testes, and obesity. This same constellation of findings was observed in a family with X-linked mental retardation (XLMR) reported by Shashi et al. [2000: Am J Hum Genet 66:469-479]. Furthermore, haplotype analysis was consistent with localization of the Shashi XLMR syndrome in Xq26-q27. Thus, the family likely represents a second occurrence of the Shashi XLMR syndrome.  相似文献   
69.
Zusammenfassung Es wird über bakteriologische, serologische und serocytologische Untersuchungen am durstenden und fastenden Menschen berichtet.Bei derSchrothschen Trockensemmelkur kam es zu einer Verschiebung der Darmflora nach der Gram-negativen Seite, trotzdem die gereichte Kost kohlehydratreich ist.Bei derFastenkur blieb die Flora mikroskopisch und kulturell gleich. Erst bei regelwidrigem Fastenbrechen mit großen Mengen Eiweiß wurden die sonst immer in den Aussaaten feststellbaren Kolonien von Bact. coli imperfectum durch typische, Milchzucker vergärende Colikeime verdrängt.Die bakteriologische Untersuchung der Rachenflora bei der Schrothschen Kur ergab ein Verschwinden der in der Vor- und Nachperiode sowie einem Teil des Hauptversuchs nachweisbaren Gram-negativen Catarrhalisflora und das Auftreten von vergrünenden Streptokokken.Die serocytologischen Untersuchungen zeigten, daß sowohl der Opsoningehalt wie die Freßtätigkeit der Phagocyten, unabhängig von den Opsoninschwankungen, durch die Durstkur anders als durch das Fasten beeinflußt werden. Die vonMorgulis vertretene Ansicht, daß die Schrothsche Trockensemmelkur auch nur eine Art Fastenkur ist, und durch Fasten dieselben Erfolge erzielt werden können, ist dadurch hinfällig.Die Untersuchungen über den Komplementgehalt des Serums sowie die Heterolysine gegen Hammelblut, die Isoagglutinine Anti A und B und die Heteroagglutinine gegen Kaninchenblut geben ein Bild von der außerordentlichen Konstanz, mit der diese Antikörper, auch unter schwierigen Verhältnissen, erhalten werden. Dieser Befund bei der Schrothschen Kur entspricht den vonFischer bei derselben Versuchsperson anläßlich einer Fastenkur erzielten Ergebnissen.  相似文献   
70.
beta-Endorphin was infused bilaterally into the medial preoptic area-anterior hypothalamic continuum at doses of 5, 10 and 40 pmol each side. The highest dose selectively abolished mounting, intromitting and ejaculating in sexually experienced male rats paired with an oestrous female. Males infused with 40 pmol beta-endorphin still followed the female, investigated her anogenital region and other parts of her body, but made abortive attempts to mount. A dose of 5 pmol beta-endorphin had no effect, but 10 pmol proved partially effective. The same males, in other tests, were allowed to ingest a highly preferred, sweet, non-calorific solution (acesulfame-K) in the absence of a female. beta-Endorphin infusions (up to 40 pmol) into the same area of the hypothalamus had no effect on this behaviour. Control males allowed simultaneous access both to an oestrous female and to the sweet solution copulated normally but reduced their ingestive behaviour, despite there being sufficient time during tests for both to occur. beta-Endorphin (40 pmol) infused into the preoptic area-anterior hypothalamic continuum under these conditions suppressed sexual interaction, but ingestion of acesulfame-K increased to values observed when the female was absent. beta-Endorphin infused into neighbouring areas of the brain had different behavioural effects. Sexual behaviour was not inhibited, and ingestion of acesulfame-K was unaltered, when beta-endorphin was infused either into the bed nucleus of the stria terminalis or the rostral ventromedial hypothalamus. However, infusions of cholecystokinin-8 into the ventromedial hypothalamus suppressed acesulfame-K ingestion in most animals, showing that the cannulae were placed in an area regulating ingestive behaviour. The inhibition of sexual behaviour after preoptic area-anterior hypothalamic continuum infusions of beta-endorphin was prevented by either pretreating rats with 1 mg/kg naloxone intraperitoneally, or by infusing a putative delta opiate receptor blocker (0.5 pmols ICI 174864) into the preoptic area-anterior hypothalamic continuum 5 min prior to beta-endorphin treatment. ICI 174864 administered alone significantly increased mount rate and reduced the post-ejaculatory refractory period in copulating males. These experiments suggest that there is both neurochemical and neuroanatomical specificity relating beta-endorphin to sexual behaviour in the male rat.  相似文献   
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