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41.
42.
Thomas Merten Paul Green Matthias Henry Nina Blaskewitz Robbi Brockhaus 《Archives of clinical neuropsychology》2005,20(6):719-726
Although symptom validity testing is an integral part of the repertory of neuropsychologists in a number of countries, this is not yet true for Germany. The German adaptations of two effort tests, the Medical Symptom Validity Test (MSVT) by Green and the Amsterdam Short-Term Memory Test (ASTM) by Schmand et al., were investigated with a German-language sample. An analog study was performed with 18 healthy experimental malingerers and 18 controls with a mean age of 25.4 years. The scenario contained detailed information about mild post-traumatic cognitive impairment, as well as an explicit warning against symptom exaggeration. In addition to MSVT and ASTM, the Trail Making Test (TMT), the Complex Figure Test (CFT), and Digit Span were performed. Half of the sample were also given Rey's 15-Item-Test (FIT). Both groups were significantly different in all effort and performance measures, with the exception of the ratio TMT-B:TMT-A. With MSVT and ASTM, correct classification of group membership was between 97 and 100%. For the ratio TMT-B:TMT-A, there was a considerable overlap in the test scores for the two groups and the sensitivity of the FIT was too low. Although the ASTM and the MSVT were identified by a number of subjects as possible effort measures, both tests obtained very good results within this analog design. 相似文献
43.
Juffs H Fowler N Saal R Grimmett K Beasley S O'Sullivan B Frazer I Gill D Thomas R 《Pathology》2004,36(1):69-76
AIMS: An important consideration in the design of a tumour vaccine is the ability of tumour-specific cytotoxic T lymphocytes (CTL) to recognise unmanipulated tumour cells in vivo. To determine whether B-CLL might use an escape strategy, the current studies compared B-CLL and normal B cell MHC class I expression. METHODS: Flow cytometry, TAP allele PCR and MHC class I PCR were used. RESULTS: While baseline expression of MHC class I did not differ, upregulation of MHC class I expression by B-CLL cells in response to IFN-gamma was reduced. No deletions or mutations of TAP 1 or 2 genes were detected. B-CLL cells upregulated TAP protein expression in response to IFN-gamma. Responsiveness of B-CLL MHC class I mRNA to IFN-gamma was not impaired. CONCLUSIONS: The data suggest that MHC class I molecules might be less stable at the cell surface in B-CLL than normal B cells, as a result of the described release of beta(2)m and beta(2)m-free class I heavy chains from the membrane. This relative MHC class I expression defect of B-CLL cells may reduce their susceptibility to CTL lysis in response to immunotherapeutic approaches. 相似文献
44.
Nina Singh 《Journal of clinical virology》2006,35(4):474-477
BACKGROUND: Late-onset CMV disease is being increasingly recognized as a significant post-transplantation complication. OBJECTIVES: To discern the impact of antiviral prophylactic strategies on the emerging syndrome of late-onset CMV disease in organ transplant recipients. STUDY DESIGN: Review of existing reports and published data relevant to antiviral prophylaxis in organ transplant recipients. RESULTS: Prevention of CMV using prophylaxis has proven effective and is widely employed in organ transplant recipients. However, late-onset CMV disease is increasingly being recognized as a significant complication in these patients. The more potent the activity of the antiviral drug and the longer duration of prophylaxis, the greater likelihood of late-onset CMV disease. CMV seronegative recipients of seropositive donor allografts appear to be at a uniquely high risk. A higher proportion of patients with late-onset CMV have tissue invasive disease. Late-onset CMV disease in liver transplant recipients conferred an independently higher risk of mortality in the first post-transplant year. Prolonged antiviral therapy may impair the recovery of CMV-specific T-cell responses. Preemptive therapy appears to be less likely to be associated with CMV disease. CONCLUSIONS: Discernment of the pathophysiologic basis of late-onset CMV warrants investigation. Preemptive therapy may be the preferable approach to CMV prophylaxis. 相似文献
45.
The exact role and timing of reactivation of telomerase, a key enzyme implicated in cellular immortalization and transformation in the multistep process of laryngeal carcinogenesis, is still unknown. We attempted to (1) determine that quantitative differences exist in the levels of telomerase catalytic subunit (hTERT) mRNA expression among different grades of laryngeal epithelial abnormalities classified according to the Ljubljana classification; (2) determine that telomerase reactivation is an important, most probably early event in laryngeal carcinogenesis; and (3) analyze whether the relative quantity of hTERT mRNA can be used as a molecular biomarker in the early detection of precancerous lesions. The relative quantity of hTERT mRNA, expressed as an hTERT index, was analyzed in 140 frozen laryngeal tissue specimens representing different morphological stages of laryngeal carcinogenesis by using a commercially available LightCycler Telo TAGGG hTERT Quantification kit. The presence and relative quantity of hTERT mRNA in laryngeal epithelium increases progressively with the degree of epithelial abnormalities. hTERT mRNA was detectable in 1/15 normal laryngeal epithelia (7%, mean hTERT index 0.02), 3/15 simple hyperplasias (20%, mean hTERT index 0.09), 10/27 abnormal hyperplasias (37%, mean hTERT index 0.18), 9/12 atypical hyperplasias (75%, mean hTERT index 0.74), 8/9 intraepithelial carcinomas (89%, mean hTERT index 1.82), and 53/62 invasive laryngeal squamous cell carcinomas (85%, mean hTERT index 2.51). Statistical analysis revealed two groups of laryngeal epithelial changes with significant differences in the levels of hTERT mRNA expression (P <.0033): (1) normal and reactive hyperplastic laryngeal epithelium (simple and abnormal hyperplasia) and (2) atypical hyperplasia (precancerous lesion), intraepithelial and invasive laryngeal squamous cell carcinoma. The results of the present study suggest that telomerase reactivation is an early event in laryngeal carcinogenesis, detectable already at the stage of precancerous laryngeal epithelial changes. Nevertheless, other genetic abnormalities appear to be necessary for progression of these epithelial abnormalities toward invasive laryngeal squamous cell carcinoma. 相似文献
46.
Lavigne R Burkal'tseva MV Robben J Sykilinda NN Kurochkina LP Grymonprez B Jonckx B Krylov VN Mesyanzhinov VV Volckaert G 《Virology》2003,312(1):49-59
The complete DNA sequence of a new lytic T7-like bacteriophage phiKMV is presented. It is the first genome sequence of a member of the Podoviridae that infects Pseudomonas aeruginosa. The linear G + C-rich (62.3%) double-stranded DNA genome of 42,519 bp has direct terminal repeats of 414 bp and contains 48 open reading frames that are all transcribed from the same strand. Despite absence of homology at the DNA level, 11 of the 48 phiKMV-encoded putative proteins show sequence similarity to known T7-type phage proteins. Eighteen open reading frame products have been assigned, including an RNA polymerase, proteins involved in DNA replication, as well as structural, phage maturation, and lysis proteins. Surprisingly, the major capsid protein completely lacks sequence homology to any known protein. Also, the strong virulence toward many clinical P. aeruginosa isolates and a short replication time make phiKMV attractive for phage therapy or a potential source for antimicrobial proteins. 相似文献
47.
48.
Herbal remedies generate more than 1.8 billion dollars in annual sales in the United States. Herbal products have been associated with a wide spectrum of hepatic toxicities. With the recent Women's Health Initiative Study demonstrating increased risk of breast cancer and cardiovascular events associated with hormone therapy, many women may resort to herbal remedies for persistent menopause symptoms. We report a case of autoimmune hepatitis likely triggered by the use of black cohosh (Actaea racemosa), an agent marketed to treat menopause symptoms. Given this case report, we recommend close monitoring of women using this herbal preparation. 相似文献
49.
Voxel-based lesion-symptom mapping 总被引:5,自引:0,他引:5
Bates E Wilson SM Saygin AP Dick F Sereno MI Knight RT Dronkers NF 《Nature neuroscience》2003,6(5):448-450
50.
Zimmermann N Doepker MP Witte DP Stringer KF Fulkerson PC Pope SM Brandt EB Mishra A King NE Nikolaidis NM Wills-Karp M Finkelman FD Rothenberg ME 《American journal of respiratory cell and molecular biology》2005,32(5):428-435
Asthma is a complex inflammatory pulmonary disorder that is on the rise despite intense ongoing research. We aimed to elucidate novel pathways involved in the pathogenesis of asthma. Employing asthma models induced by different allergens (ovalbumin and Aspergillus fumigatus), we uncovered the involvement of two members of the small proline-rich protein (SPRR) family, SPRR2a and SPRR2b, known to be involved in epithelial differentiation but not allergic disease. In situ hybridization revealed induction of SPRR2 signal in a subset of bronchial epithelial cells and mononuclear cells associated with inflammation after allergen challenge. Allergen-induced SPRR2 mRNA accumulation in the lung occurred in a time-dependent manner, with peak expression 10-96 h after a second ovalbumin challenge. Transgenic overexpression of interleukin (IL)-13 in the lungs resulted in a marked increase of SPRR2 expression, and allergen-induced SPRR2 expression was significantly decreased in IL-13-deficient mice. Studies in gene-targeted mice revealed that allergen-induced SPRR2 was dependent upon STAT6. Finally, we aimed to determine if the induction of SPRR2 by allergen was tissue specific. Notably, SPRR2 was markedly increased in the small intestine after induction of allergic gastrointestinal inflammation. Thus, SPRR2 is an allergen- and IL-13-induced gene in experimental allergic responses that may be involved in disease pathophysiology. 相似文献