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91.
The type specificity of the human papillomavirus (HPV) Hybrid Capture Tube (HCT) test was evaluated by using typing with PCR (MY09-MY11)-restriction fragment length polymorphism (RFLP) and sequencing. All samples HCT test positive for only low-risk HPV (n = 15) or only high-risk HPV (n = 102) were confirmed, whereas 9 of 12 HCT test double-positive samples contained only high-risk HPV types as determined by PCR-RFLP. Several high-risk HPV types (HPV-53, -58, -62, -66, -CP8304, and -MM4) not included in the HCT test were indeed detected, indicating a broader detection range with retained distinction between low-risk and high-risk HPV types.  相似文献   
92.
Previous findings have demonstrated the existence of a visual peripersonal space centered on the hand in humans and its modulatory effects on tactile perception. A strong modulatory effect of vision on touch perception was found when a visual stimulus was presented near the hand. In contrast, when the visual stimulus was presented far from the hand, only a weak modulatory effect was found. The aim of the present study was to verify whether such cross-modal links between touch and vision in the peripersonal space centered on the hand could be mediated by proprioceptive signals specifying the current hand positions or if they directly reflect an interaction between two sensory modalities, i.e., vision and touch. To this aim, cross-modal effects were studied in two different experiments: one in which patients could see their hands and one in which vision of their hands was prevented. The results showed strong modulatory effects of vision on touch perception when the visual stimulus was presented near the seen hand and only mild effects when the vision of the hand was prevented. These findings are explained by referring to the activity of bimodal neurons in premotor and parietal cortex of macaque, which have tactile receptive fields on the hand, and corresponding visual receptive fields in the space immediately adjacent to the tactile fields. One important feature of these bimodal neurons is that their responsiveness to visual stimuli delivered near the body part is reduced or even extinguished when the view of the body part is prevented. This implies that, at least for the hand, the vision of the hand is crucial for determining the spatial mapping between vision and touch that takes place in the peripersonal space. In contrast, the proprioceptive signals specifying the current hand position in space do not seem to be relevant in determining the cross-modal interaction between vision and touch.  相似文献   
93.
Association studies have identified the interleukin-1 receptor antagonist gene allele 2(IL-1RN*2) as a marker of susceptibility in ulcerative colitis (UC). This study investigated the significance of the IL-1RN genotype with respect to protein and mRNA expression in the colonic mucosa. Homogenates of rectal biopsies from 99 UC and 54 controls were assayed for cytokines IL-1ra, IL-1a and IL-1b using ELISA. IL1RN, IL1A and IL1B genotypes were determined using restriction-enzyme analysis. The ability of the two IL1RN alleles to generate steady-state mRNA accumulation was assessed in the colonic mucosa of seven heterozygous patients. Stepwise linear regression demonstrated that IL-1RN genotype (P=0.001), diagnosis (P<0.0001) and treatment (P<0.03) were independent factors associated with the IL-1ra protein level whilst IL1RN genotype (P=0.005) and macroscopic inflammatory grade (P<0.0001) were associated with the IL-1ra/ total IL-1 ratio. The IL1RN*2 correlated with reduced IL-1ra and IL-1ra/IL-1 ratio with a gene dosage effect. In heterozygous UC patients the ratio of allele 1 mRNA / allele 2 steady state mRNA was always greater than 1 (range: 1.2-3.1) (P=0.018). The IL-1RN*2 is associated with reduced levels of IL-1ra protein and IL-1RN mRNA in the colonic mucosa, providing a biologically plausible explanation for the observed association of the allele with the disease.  相似文献   
94.
Pituitary adenylate cyclase-activating polypeptide (PACAP) is present in many regions of the hypothalamus including the paraventricular nucleus (PVN). In this study the anatomical relationship between PACAP- and thyrotropin-releasing hormone (TRH)-immunoreactive neuronal elements was investigated in the rat hypothalamus. Using a well-characterized mouse monoclonal antibody against PACAP and a rabbit polyclonal antiserum against TRH, we found numerous nerve fibers with PACAP-immunoreactivity (ir) closely apposed to TRH neurons in the PVN suggesting synaptic contacts. Electron microscopy confirmed the presence of synapses between PACAP-ir terminals and TRH-ir perikarya and various dendritic profiles as well as between PACAP-ir terminals and unlabeled perikarya and small- to medium-sized dendrites. Coexistence of the two peptides in perikarya of the PVN was limited to only a few neurons in the periventricular subdivision, but PACAP-ir and TRH-ir extensively coexisted in perikarya of the perifornical cell group, medial preoptic area, lateral hypothalamus and dorsomedial nucleus. The interactions between PACAP-containing neuronal processes and TRH neurons in the PVN raise the possibility that PACAP modulates the secretion of TRH destined for regulation of anterior pituitary TSH. The more general association between PACAP and TRH in other regions of the hypothalamus suggests a further role for PACAP as a cofactor in the function of TRH neurons.  相似文献   
95.
1. Extracellular single neuron activity was recorded in the lateral hypothalamic area (LHA) of awake, behaving monkeys, with particular regard to the feeding-related functional characteristics of glucose-sensitive (GS) versus glucose-insensitive (GIS) neurons. Firing rate changes were recorded by means of carbon fiber, multibarreled glass microelectrodes during 1) microelectrophoretic application of various chemicals, 2) gustatory and olfactory stimulation, and 3) a high fixed-ratio schedule (FR) bar press feeding task. 2. In 336 neurons examined, 91 (27%) were suppressed by electrophoretically administered glucose, and so they were designated as GS cells. The 245 neurons (73%) in which the firing rates did not change during glucose applications were pronounced GIS. The 179 GS and GIS cells tested exhibited different responses to the catecholamines (CAs), noradrenaline (NA) and dopamine (DA), both of which are intimately involved in the control of feeding. More GS neurons responded to NA than did GIS cells; the predominant effect of both CAs on GS neurons was inhibition. 3. The taste responsiveness of 111 LHA neurons was examined. Fifty-seven cells (52%) showed responses to gustatory stimulation. Of 50 GS neurons tested, 33 (66%) exhibited firing rate changes to tastes. On the contrary, only 24 (39%) of the 61 GIS neurons examined responded to gustatory stimuli. Activity changes of GS neurons commonly occurred to two or more tastants, in distinction to the relative gustatory specificity shown by GIS cells. 4. Two hundred fifty-six (84%) of the 303 neurons tested responded during one or more phases of the bar press feeding task. Most activity changes occurred during the bar press (BP) and reward (RW) periods, however numerous phasic responses to cue light (CL) and cue tone (CT) were also observed. A higher proportion of the GS neurons showed task-related activity changes than did the GIS cells (77, 95% and 179, 81%, respectively). GS neurons responded more during the BP phase and to the food reward; GIS cells were more responsive during the CL that enabled acquisition and the CT that signaled reward. Thus GS neurons were responsive during the acquisition and consumption of reward, whereas GIS cells responded to external cues signaling both of these events. The gustatory neurons displayed specific task-related activity changes only in the CL (GIS cells) and BP phases (GS neurons), that is, in phases most intimately involved in sensory-motor integration. 5. Two-thirds of the 30 GS neurons tested were responsive to both gustatory and olfactory stimulation as opposed to only one-third of GIS cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
96.
OBJECTIVE: Our aim was to deepen the understanding of the psychosomatic aspects of temporomandibular joint (TMJ) pain dysfunction syndrome. Patients affected by this syndrome were compared with both healthy subjects and psychiatric patients, using both self-report and physician-scored psychological measures. METHODS: Three sex- and age-matched groups were recruited: a TMJ group (n = 32), a healthy group (n = 22) and a psychiatric group (n = 22). The psychiatric group consisted of outpatients diagnosed as having a DSM-IV anxiety or depressive disorder of mild to moderate severity. Psychometric assessment included the Minnesota Multiphasic Personality Inventory (MMPI) and the Hamilton Anxiety Rating Scale (HARS). RESULTS: Psychiatric patients scored higher than both the comparison groups on all but one of the MMPI scales; the majority of the differences were significant or approached significance. TMJ patients scored higher than healthy controls on the Hs (hypochondriasis; p< or =0.01), Hy (hysteria; p< or =0.01) and D (depression; p< or =0.05) scales. Psychiatric patients scored higher than TMJ patients on the HARS psychic anxiety subscale (p< or =0.05), while TMJ patients scored higher than psychiatric patients on the somatic anxiety subscale (p< or = 0.05). CONCLUSIONS: Certain personality characteristics were associated with TMJ dysfunction. However, further longitudinal studies should be performed to properly assess causal relationships. Despite signs of neuroticism, anxiety and depression, patients with TMJ dysfunction differed from anxious and depressed patients. While the latter displayed a higher level of psychopathology, each group was characterised by a distinct pattern of anxiety symptoms. In addition, a substantial proportion of TMJ patients had little awareness of their inner states and emotions.  相似文献   
97.
BACKGROUND: Lethal varicella in immunocompetent hosts is rare and its pathogenesis is largely unknown. The discovery of glycoprotein E (gE) mutants showing attributes consistent with increased virulence in vitro and in animal models, provided a possible molecular mechanism underlying a more aggressive virus infection. However, these mutants have never been associated with unusually severe clinical cases. OBJECTIVES: To varicella-zoster virus (VZV) mutations that correlate with increased virulence. RESULTS: We report a case of fatal hepatitis caused by a VZV bearing a novel mutation on the 3B3 monoclonal antibody epitope of gE in an immunocompetent host. CONCLUSIONS: This report describes a mutant VZV responsible for an aggressive clinical course in an immunocompetent host. Linking these severe clinical presentations of VZV infection to virus mutations might provide insights into the underlying pathogenic mechanisms.  相似文献   
98.
PURPOSE: The role of genetic susceptibility to esophageal adenocarcinoma and its precursor lesion Barrett esophagus has not been fully elucidated. This study investigated the effect of polymorphisms in the manganese superoxide dismutase (MnSOD) and NAD(P)H:quinone oxidoreductase 1 (NQO1) genes in modulating the risk of developing Barrett esophagus or esophageal adenocarcinoma. METHODS: A total of 584 patients (146 esophagitis, 200 Barrett esophagus, 144 esophageal adenocarcinoma, and 94 controls) were genotyped for the MnSOD C14T and NQO1 C609T polymorphisms using polymerase chain reaction and restriction fragment length polymorphism analysis. RESULTS: The NQO1 TT genotype was less common in Barrett esophagus (2.0%) and esophageal adenocarcinoma (1.4%) patients, compared with both esophagitis patients (7.6%) and controls (5.4%). After adjustment for sex, age, body mass index, reflux symptoms, and smoking status, patients with the homozygous TT genotype had a 4.5-fold decreased risk of developing Barrett esophagus (odds ratio = 0.22, 95% confidence interval = 0.07-0.76, P = 0.01) and a 6.2-fold decreased risk of esophageal adenocarcinoma (odds ratio = 0.16, 95% confidence intervals = 0.03-0.94, P = 0.04) compared with individuals with the TC and CC genotypes. No significant differences between groups were observed for the MnSOD polymorphism (P = 0.289). CONCLUSIONS: Overall, the results of this study suggest that the NQO1 TT genotype may offer protection from reflux complications such as Barrett esophagus and esophageal adenocarcinoma.  相似文献   
99.
Unique finding of prostatic tissue in a benign cystic ovarian teratoma   总被引:1,自引:0,他引:1  
Benign cystic ovarian teratomas are neoplasms with a 46,XX karyotype originating from a single abnormal ovarian germ cell after the first meiotic division. Since these tumors lack the Y chromosome (required for production of the H-Y antigen that is presumably obligatory for embryonic male sexual differentiation), identifiable male sex organ structures should not be found in the tumor. We report a case in which prostatic tissue was identified in a benign cystic ovarian teratoma.  相似文献   
100.
The balance between interleukin-1 (IL-1) and its competitive antagonist IL-1 receptor antagonist (IL-1Ra) may contribute to the pathogenesis of rheumatoid arthritis (RA). We analysed the frequency of different alleles in the IL-1B gene (at -511 and at +3954) as well as in the IL-1Ra gene (at +2018) in an association study involving 297 RA patients and 112 healthy controls from the same geographic area. We tested associations with RA susceptibility or severity, and with circulating levels of IL-1Ra and IL-1beta. Carriage of the rare IL-1B (+3954) allele 2 was increased in destructive arthritis (DRA) as compared to non-destructive arthritis (NDRA) (OR 1.7, 95% CI 1.1-2.8, 49.0% vs 35.9%) and controls (OR 1.7, 95% CI 1.1-2.8, 35.8%). Patients carrying this allele had a more destructive (Larsen wrist radiological index: mean +/- s.e.m., 2.1 +/- 0.2 vs 1.6 +/- 0.1, P = 0.005; Steinbrocker functional index: 2.4 +/- 0.1 vs 1.9 +/- 0.1, P = 0.002) and active disease (Ritchie articular index: 8.1 +/- 0.8 vs 5.3 +/- 0.6, P = 0.002; erythrocyte sedimentation rate (ESR): 36.6 +/- 2.9 mm/h vs 25.3 +/- 1.8 mm/h, P = 0.002). This contribution was independent from that of HLA DR4/DR1 to severity. IL-1Ra plasma levels adjusted to ESR values were significantly lower in IL-1B2 (+3954) positive than negative RA patients (1.0 +/- 0.1 vs 1.2 +/- 0.1 ng/ml, P = 0.01). This IL-1B (+3954) gene polymorphism may be an important marker for the severity of joint destruction in RA and is associated with an imbalance in IL-1Ra production. As this genetic association was independent and additive to the risk of HLA DR4/DR1 status, it could be a useful addition to HLA-DR4/1 as a genetic prognostic marker early in the course of the disease.  相似文献   
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