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61.
Relationships between striatal dopamine denervation and frontal executive tests in Parkinson's disease 总被引:2,自引:0,他引:2
Indirect evidence from human and monkey investigations supports the idea that impaired frontal tasks in Parkinson's disease (PD) may result from striato-frontal disruption caused by dopamine (DA) denervation of the caudate nucleus. To directly investigate this hypothesis, we used PET with 11C-S-Nomifensine (11C-S-NMF), a sensitive marker of striatal DA denervation, in 10 non-demented PD patients in whom two frontal executive tests, the object alternation (OA) and the conditional associative learning (CAL) tasks, thought to reflect mainly set-shifting/inhibition and planning, respectively, were given. In addition, the central executive function of verbal working memory was assessed with the Brown Peterson paradigm (BPP). We found a highly significant correlation between right caudate 11C-S-NMF specific binding and OA performance, less significant and reverse-direction correlations between CAL performance and putamen 11C-S-NMF binding, and no significant correlation with BPP performance. Thus, caudate DA denervation may subtend poor set-shifting/inhibition process in PD. Our results also point to distinct and complex relationships between striatal DA and specific frontal tasks. 相似文献
62.
63.
Lymphoma arising in an adenolymphoma 总被引:1,自引:0,他引:1
A malignant lymphoma that originated in association with an adenolymphoma (Warthin's tumor) of the parotid salivary gland is reported. The occurrence of lymphomas in salivary glands is discussed briefly. 相似文献
64.
Background: Posttraumatic stress disorder (PTSD) is common in refugees but its association with longer-term psychosocial dysfunction remains unclear. We examined whether a subgroup of refugees with comorbid PTSD and depression were at particularly high risk of disability. We also investigated whether specific trauma experiences were linked to this comorbid pattern. Methods: Consecutive Bosnians (and one or two compatriots nominated by them) were recruited from a community centre, yielding a total sample of 126 participants (response rate 86%). Measures included a trauma inventory, the Clinician Administered PTSD Scale (CAPS) (Blake et al., 1995) and the depression module of the Structured Clinical Interview (SCID) (First et al., 1997). Results: Three diagnostic groupings emerged: normals (n=39), pure PTSD (n=29), and comorbid PTSD and depression (n=58). Of four trauma dimensions derived from principle components analysis (human rights violations, dispossession and eviction, life threat and traumatic loss), life threat alone was associated with pure PTSD, with life threat and traumatic loss both being associated with comorbidity. Compared to normals and those with pure PTSD, the comorbid group manifested more severe PTSD symptoms as well as higher levels of disability on all indices (global dysfunction: odds RATIO=5.0, P<0.001, distress: odds RATIO=6.0, P<0.001, social impairment: odds ratio 5.9, P<0.001, and occupational disability: odds ratio 5.0, P<0.001). Limitations: Recruitment was not random, the sample size was modest, and trauma event endorsement was based on retrospective accounts. Conclusions: The combination of life threat and traumatic loss may be particularly undermining to the psychological well-being of refugees and consequent comorbidity of PTSD and depression may be associated with longer-term psychosocial dysfunction. The findings raise the question whether the comorbid pattern identified should be given more recognition as a core posttraumatic affective disorder. 相似文献
65.
Bb2Bb3 regulation of murine Lyme arthritis is distinct from Ncf1 and independent of the phagocyte nicotinamide adenine dinucleotide phosphate oxidase
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Crandall H Ma Y Dunn DM Sundsbak RS Zachary JF Olofsson P Holmdahl R Weis JH Weiss RB Teuscher C Weis JJ 《The American journal of pathology》2005,167(3):775-785
Several quantitative trait loci regulating murine Lyme arthritis severity have been mapped, including a highly significant linkage found on chromosome 5, termed Bb2Bb3. Within this region, the Ncf1 gene of the phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase has recently been identified as a major regulator of arthritis severity in rodent models of rheumatoid arthritis, an effect attributed to protective properties of reactive oxygen species. To assess the role of Ncf1 in Lyme arthritis, we introgressed Bb2Bb3 from severely arthritic C3H/He mice onto mildly arthritic C57BL/6 mice. This increased Lyme arthritis severity, whereas the reciprocal transfer conferred protection from disease. A single nucleotide polymorphism was identified in the Ncf1 gene that did not influence the protein sequence or expression of Ncf1. Although polymorphonuclear leukocytes from C57BL/6 mice generated a greater oxidative burst than polymorphonuclear leukocytes from C3H/He mice, studies with the Bb2Bb3 congenic mice demonstrated this difference was not linked to Ncf1 alleles. Furthermore, Lyme arthritis severity was not altered in mice lacking either the Ncf1 or Gp91phox subunits of the NADPH oxidase complex. Together, these results argue that Ncf1 is not a candidate gene for regulation of Lyme arthritis and reveal Lyme arthritis to be independent of NADPH oxidase activity, distinguishing it from other models of rheumatoid arthritis. 相似文献
66.
Genetic control of natural immunity to ecotropic mouse leukemia viruses: production of endogenous immunogen.
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Mice of the AKR and C57L strains naturally produced low titers of antibody against ecotropic murine leukemia viruses (MuLV). The F1 hybrid of these strains produced anti-MuLV antibody in higher titer than mice of either of the parental strains. Progeny of the genetic backcross C57L X (AKR X C57L)F1 segregated for the production of infectious ecotropic MuLV (according to the Akv-1 and Akv-2 loci) and for the production of antibody against MuLV. All mice that contained infectious MuLV produced anti-MuLV antibodies. Thus, the persistent production of high-titered MuLV in these mice did not result in immunological tolerance towards viral antigens. In contrast, mice that did not contain infectious MuLV could be separated into antibody-producing and -nonproducing classes. The absence of detectable antibody to MuLV in an individual mouse was invariably associated with a virus-free phenotype. Antibody against MuLV reacted primarily with p15 and gp70 proteins of the viral envelope. It was concluded that overt production of endogenous ecotropic MuLV served as a major immunogenic stimulus for the production of anti-MuLV antibody in these mice. 相似文献
67.
Pierre Zachary Murielle Ullmann Saadi Djeddi Nicolas Meyer Marie-Josée Wendling Evelyne Schvoerer Fran?oise Stoll-Keller Jean-Pierre Gut 《Journal of clinical virology》2005,34(3):207-10; discussion 216-8
BACKGROUND: Most studies evaluating antibody detection assays are conducted on samples from healthy blood donors but not on samples of hospitalized patients which can show non-specific reactions. OBJECTIVES: To compare the performance of three commercial automated assays for the detection of hepatitis C virus (HCV) antibodies, Monolisa anti-HCV Plus version 2, Axsym anti-HCV 3.0 and Vitros anti-HCV, on a population of hospitalized patients. STUDY DESIGN: The specificity of the assays was prospectively evaluated in 2020 routine serum samples. In order to assign the serostatus of each sample, those giving positive or discordant results were further tested by three immunoblots and by RT-PCR (Roche). Moreover, the sensitivity was evaluated on eight commercial HCV seroconversion panels. RESULTS: The Monolisa, Axsym and Vitros assays showed specificities of 99.64%, 99.12% and 99.33%, respectively. Concerning the sensitivity, among 49 samples, the number of positive results was 21, 24 and 24 for the Monolisa, Axsym and Vitros kits, respectively. The differences were not statistically significant at an alpha risk of 5%. CONCLUSIONS: All assays appeared to be reliable for routine screening, but there were a surprising number of indeterminate samples that could not be resolved by confirmatory tests. 相似文献
68.
Afferent and sympathetic postganglionic nerve cell bodies projecting in the splenic nerve of the cat have been labeled retrogradely with horseradish peroxidase (HRP) in order to study numbers and locations of these neurons. Labeled somata were found bilaterally in dorsal root and sympathetic paravertebral ganglia T3-L2 with a maximum in T10-T13 and in the coeliac superior mesenteric ganglion complex. About 13,200 neurons project into the splenic nerve of the cat, 12,550 being postganglionic and 650 afferent. About 98% of the postganglionic neurons were located in prevertebral and 2% in paravertebral sympathetic ganglia. About 73% of the afferent and 66% of the postganglionic paravertebral neurons were located on the left side. The density of the splenic innervation is about 3-4 times higher than that of the kidneys when normalized to the weight of both organs. It is discussed whether the afferent and sympathetic innervation of the spleen is not only involved in cardiovascular functions but also in regulation of the immune response of this organ. 相似文献
69.
Morice P Leblanc E Rey A Baron M Querleu D Blanchot J Duvillard P Lhommé C Castaigne D Classe JM Bonnier P;GCCLCC SFOG 《Human reproduction (Oxford, England)》2005,20(5):1379-1385
BACKGROUND: Results of conservative management of epithelial ovarian cancer (EOC) remain controversial in the literature. The aim of this study was to assess the clinical outcomes and fertility following fertility-sparing surgical management of EOC in a retrospective multicentre study. METHODS: A multicentre retrospective study was performed by members of two French groups. Six inclusion criteria were defined: (i) Histological review by the same pathologist; (ii) age < or =40 years; (iii) conservative management; (iv) complete peritoneal staging; (v) delivery of a platinum-based chemotherapy in stage > or = IC; and (vi) follow-up >1 year. RESULTS: Thirty-four patients fulfilled the inclusion criteria: 30 had stage IA disease; three had stage IC and one had stage IIA. Eleven patients had recurrence: 10 patients had invasive disease and one had borderline recurrence. Among 10 patients with invasive recurrence, initial stage and grade were: stage IA G1, n = 1; stage IA G2, n = 4; stage IA G3, n = 1; and stage> or = IC, n = 4. All patients with stage > IA had recurrence. Ten pregnancies were observed in nine patients. CONCLUSION: Conservative surgery for patients with EOC could be considered in young patients with stage IA G1 disease. This procedure should not be performed in patients with FIGO stage > IA. 相似文献
70.