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141.
Mawrin C Kirches E Krause G Wiedemann FR Vorwerk CK Bogerts B Schildhaus HU Dietzmann K Schneider-Stock R 《Neuroreport》2004,15(6):939-943
One possible cause for the neuronal loss in sporadic amyotrophic lateral sclerosis (S-ALS) is an increase of free radicals, which may produce oxidative damage to susceptible biomolecules, which, in turn, can damage the mitochondrial DNA (mtDNA). Following laser microdissection of single motor neurons from paraffin-embedded autopsy tissue, we analyzed the presence of a common mtDNA deletion, the 5 kb common deletion (CD). Spinal cord neurons showed slightly higher CD detection rate in patients than controls (94% vs 75%). No significant differences were found between patients and controls for neurons derived from other motor or non-motor regions. A PCR assay of serial DNA dilutions (10-fold) showed no CD level differences between motor neurons in S-ALS and controls. These data suggest that neuronal death in S-ALS is not associated with significant accumulation of mtDNA deletions. 相似文献
142.
Human wild-type alpha-synuclein impairs neurogenesis 总被引:2,自引:0,他引:2
Winner B Lie DC Rockenstein E Aigner R Aigner L Masliah E Kuhn HG Winkler J 《Journal of neuropathology and experimental neurology》2004,63(11):1155-1166
Neurodegenerative diseases classified as synucleinopathies are characterized by alpha-synuclein inclusions. In these disorders, alpha-synuclein accumulates within glial or neuronal cells in the brain including regions of adult neurogenesis. We hypothesized a pathophysiological role for alpha-synuclein in newly generated cells of the adult brain and in this study examined regions of neurogenesis in adult mice overexpressing human wild-type alpha-synuclein under the control of the platelet-derived growth factor promoter. The number of proliferating cells and the fate of newly generated cells were analyzed in the olfactory bulb system and in the hippocampal dentate gyrus. There were no effects on proliferation detectable; however, significantly less neurogenesis and fewer neurons were observed in the olfactory bulb as well as in the hippocampus of adult human alpha-synuclein mice compared to control littermates. This effect was almost exclusively due to diminished survival of neuronal precursors in the target regions of neurogenesis. Our data imply that the finely tuned equilibrium of neuronal cell birth and death in neurogenic regions may be altered in human alpha-synuclein-overexpressing mice. We hypothesize that reduced adult neurogenesis in the olfactory bulb may contribute to olfactory deficits in neurodegenerative disorders associated with alpha-synuclein inclusions. 相似文献
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144.
Summary The purpose of the paper is to evaluate the psychometric properties of the impact factor as an assessment procedure. Detailed criteria regarding theoretical underpinnings, test administration, scoring and interpretation are applied. The impact factor appears to be of limited use for deciding which journals to subscribe. It is not suitable for evaluating achievements of individual scientists and research groups. The impact factor contains serious sources of errors and flaws resulting in strong biases against culture- and language-bound medical subspecialties and non-Anglo-American countries. Possible alternatives are discussed.Prof. Dr. Elmar Brähler is the director of the Department of Medical Psychology and Medical Sociology, University Medial
School in Leipzig. Dr. Manfred Beutel is a professor of the Department of Psychosomatic and Psychotherapy, University
Medical School in Gießen. Dr. Oliver Decker is an assistant at the Department of Medical Psychology and Medical Sociology,
University Medical School in Leipzig 相似文献
145.
146.
Serum levels of squamous cell carcinoma antigen as a predictor of inguinofemoral lymph node metastasis in patients with vulvar cancer 总被引:1,自引:0,他引:1
Nather A Sami A Hefler L Leodolter S Joura EA 《The Journal of reproductive medicine》2002,47(9):718-720
OBJECTIVE: To evaluate the predictive value of preoperatively determined squamous cell carcinoma antigen (SCC-Ag) serum levels for the risk of inguinofemoral lymph node metastasis. STUDY DESIGN: In this retrospective trial, preoperative serum levels of SCC-Ag in 29 patients with invasive squamous cell vulvar cancer (pT1 + 2) were evaluated and compared with nodal status. RESULTS: Twenty patients had negative inguinofemoral nodes, whereas in nine an inguinofemoral lymph node metastasis could be observed. The median SCC-Ag in women with negative nodes was 1.3 micrograms/L (0.2-11.5) and with positive nodes, 2.7 micrograms/L (0.4-9.1) (P = .35). CONCLUSION: Measurement of the serum level of SCC-Ag cannot be used for preoperative evaluation of the risk of lymph node metastasis in patients with clinically localized tumors since there is a significant overlap between both cohorts. 相似文献
147.
Mayerhofer K Bodner-Adler B Bodner K Rabl M Kaider A Wagenbichler P Joura EA Husslein P 《The Journal of reproductive medicine》2002,47(6):477-482
OBJECTIVE: To investigate the influence of the traditional hands-on versus the innovative hands-poised method on the risk of perineal trauma during vaginal delivery and on neonatal outcomes. STUDY DESIGN: In a prospective, randomized, multicenter study, 1,161 of 1,505 women giving birth at the Departments of Obstetrics and Gynecology of the University Hospital of Vienna and Semmelweis Women's Hospital, Vienna, between February and September 1999, were randomized into the trial. In the hands-on method, the left hand of the midwife puts pressure on the infant's head, and the right hand is placed against the perineum. In the hands-poised method, the midwife guides the parturient through the birth without touching the perineum, prepared to apply light pressure on the infant's head. RESULTS: One hundred eighty-seven of 574 women (32.5%) in the hands-on group and 180 of 502 women (35.8%) in the hands-poised group experienced perineal tears (P = .5). Sixteen women (2.7%) treated with the hands-on method developed third-degree perineal tears as compared with five women (0.9%) treated with the hands-poised method (P < .05). In the hands-on group, 103 women (17.9%) underwent episiotomy as compared with 51 cases (10.1%) in the hands-poised group (P < .01). No significant differences in neonatal outcomes were observed between the two groups. CONCLUSION: Our data suggest that a policy of hands-poised care is more suitable for preserving the perineum during birth and is a safe and effective birthing alternative for women. 相似文献
148.
Hainz U Aigner K Asch E Berger P Böhmer F Feldkircher B Horwath B Jenewein B Kassal H Kistner O Mack H Pfeiffer KP Pils K Plank J Renner D Saurwein-Teissl M Schwanzer E Trieb K Grubeck-Loebenstein B 《Wiener klinische Wochenschrift》2002,114(5-6):187-193
OBJECTIVE: The aim of the study was to evaluate, if elderly persons are sufficiently protected against infectious diseases by vaccination. PROBANDS AND METHODS: 300 elderly (> 60 years) and 300 young (< 35 years) persons from five Austrian cities were recruited according to the criteria of a field study. Antibody concentrations against tetanus, diphtheria, tickborne encephalitis and influenza were assessed by ELISA or by haemagglutination inhibition test. Disease and vaccination histories were recorded. RESULTS: The results of the study demonstrate that protection against infectious diseases was frequently insufficient in the elderly. This was partly due to the fact that old persons were not vaccinated according to recommended strategies. However, low antibody concentration and a short duration of protective humoral immunity were also observed in many elderly persons in spite of regular vaccination. This was not only the case in frail, but also in healthy elderlies. CONCLUSION: The data demonstrate that vaccination has a relatively weak and short-lasting effect in old age. The results of the study should stimulate discussions about strategies how vaccinations can be made more effective in old age. Improved campaigns, shortened vaccination intervals as well as the design of novel vaccines tailored to fulfill the specific demands of the aging immune system are imaginable. 相似文献
149.
150.
Pathology results in [18F]fluorodeoxyglucose positron emission tomography of the thyroid gland 总被引:3,自引:0,他引:3
Wolf G Aigner RM Schaffler G Schwarz T Krippl P 《Nuclear medicine communications》2003,24(12):1225-1230
The aim of this retrospective study was to evaluate pathologically increased uptake of [18F]fluorodeoxyglucose (18F-FDG) in positron emission tomography (PET) results of the thyroid gland. Results of 18F-FDG PET and [99mTc]pertechnetate scintigraphy of the thyroid gland are shown, compared to each other and discussed. In a retrospective study 16 patients underwent whole-body 18F-FDG PET and [99mTc]pertechnetate scintigraphy of the thyroid gland within 3 weeks. In addition, an examination of the thyroid gland by using ultrasound and laboratory tests was carried out. The 18F-FDG PET studies were carried out on a dedicated whole-ring PET scanner. Eight patients had a pathological FDG uptake in the thyroid and a cold nodule in [99mTc]pertechnetate scintigraphy of the thyroid gland (in 7/8 cases histology showed malignancy). Five patients had an inhomogeneous FDG uptake in the thyroid gland and were suspected of thyroiditis in 18F-FDG PET (in 3/5 cases thyroiditis was confirmed). Three patients had an especially low FDG uptake compared to normal physiological FDG uptake (no malignancy). Results from studies using 18F-FDG represent a growing body of evidence showing the differentiation between malignant and benign disease: we saw many pathological results in the thyroid gland. High uptake of 18F-FDG in the thyroid gland suggests possible malignancy. Thyroiditis can only be suspected based upon the results of 18F-FDG PET. We conclude that 18F-FDG PET has a potential clinical impact for detecting possible malignant lesions of the thyroid gland, but further studies, in which a higher number of patients are evaluated, are necessary. 相似文献