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Helmut Seidel Barbara Harazin Kristina Pavlas Christine Sroka Jörg Richter Ralph Blüthner Udo Erdmann Jan Grzesik Barbara Hinz Reinhard Rothe 《International archives of occupational and environmental health》1988,61(1-2):95-106
Summary This study was carried out in order: (1) to examine the effects of isolated and combined prolonged exposures to noise and whole-body vibration on hearing, vision and subjectively experienced strain, and (2) to check the combined effects with repeated exposures. Six male subjects were exposed twice to noise (N) at 92 dBA, whole-body vibration (V) in the Z-axis at 4 Hz and 1.0 ms–2 rms, and noise and vibration (NV) for 90 min with each condition. Temporary threshold shifts of hearing (TTS) and their integrals (ITTS) were measured at 4, 6, 10, and 12 kHz. Visual acuity was examined by means of a very sensitive test. Cross-modality matching (CMM) of the handgrip force was used to judge the subjectively experienced strain. NV induced a clear tendency of higher TTS and ITTS than N, with several significant differences most pronounced at 10 kHz. With repeated exposures, the effect of NV decreased, while the reactions to N and V remained unchanged. The individual reactions to NV differed. The influence of the duration of exposures on vision depended on the condition; N caused time-dependent changes, whereas V did not. CMM-data increased with the duration of the exposure during V and NV. N was generally judged to be more straining than V; NV caused higher strain than V during the first 30 min of exposure only. Correlations between different effects suggest certain links between them. Additionally, less motivation — daily obtained by a questionnaire — often correlated with higher ITTS during N and NV. The results also illustrate the combined effects on the individual susceptibility, repetition of exposure, the kind of response, and, possibly, the actual psychic state.Abbreviations CMM
cross-modality matching
- MVC
maximum voluntary contraction force
- N
exposure condition: noise level 92dBA, no whole-body vibration
- NV
exposure condition: combined exposure to noise with a level of 92 dBA and wholebody vibration with 4 Hz, 1 ms–2 rms
- V
exposure condition: whole-body vibration with 4 Hz, 1 ms–2 rms
- TTS
temporary threshold shift
- ITTS
integral of temporary threshold shift
- WBV
whole-body vibration in the common sense
This work was done in the Temporary International Research Team on Combined Effects of Noise and Vibration of the Council of Mutual Economic Assistance of the Socialist Countries. The authors gratefully acknowledge the help and assistance of L.-M. Brumm, Y. Bening, M. Godau, G. Weber, and R. Vizcaino. 相似文献
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An extrachromosomal nucleic acid element was detected in high-molecular-weight DNA preparations formBabesia equi merozoites. This extrachromosomal element was shown to be DNA rather than RNA and had an apparent fragment size of about 9 kilobasepairs (kb). Hybridization experiments using purified 9-kb DNA as a probe revealed sequence homologies with extrachromosomal DNA from two otherBabesia species. 相似文献
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Effect of change of fecal bile acid excretion achieved by operative procedures on 1,2-dimethylhydrazine-induced colon cancer in rats 总被引:5,自引:0,他引:5
Dr. Krisztina Morvay M.D. Károly Szentléleki M.D. Géza Török M.D. Alan Pintér M.D. Mátyás Börzsönyi M.D. Reinhard Nawroth DSc 《Diseases of the colon and rectum》1989,32(10):860-863
The effect of bile on the development of 1,2-dimethylhydrazine (DMH)-induced colon cancer was studied in male Wistar rats. Experimental operative models were created, in which in Group 1, the half intestinal tract, the ileum, and the right side of colon were released from bile. In Group 2, both sides of the colon contained bile. The sham operated animals formed Group 3. These techniques changed the concentration of bile acid in different parts of the colon, and the daily total fecal bile acid excretion as well. After DMH treatment, the relationship between these changes of bile acid level and the development of colon cancer was studied. Significantly more tumors than in the control group were found if the daily total bile acid level and the bile acid concentration in the left side of the colon were increased. Our findings show an unambiguous connection between the fecal bile acid level and the incidence of DMH-induced colon cancer. 相似文献
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Erkki Lotspeich Markus Schoene Heinz Gerngroß Roland Schmidt Reinhard Steinmann Marco Ramadani Susanne Gansauge 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):559-566
Introduction Postoperative treatment for colorectal cancer depends on tumor stage as defined by the International Union Against Cancer
(UICC). Adjuvant chemotherapy is not recommended in patients without lymph node involvement (UICC stages I and II). As many
as 20–30% of these patients, however, will develop recurrence.
Aims and objectives We conducted this study to determine the presence of disseminated tumor cells in the lymph nodes by quantitative real-time
polymerase chain reaction (QRT-PCR) for cytokeratin 20 (CK20) in an attempt to provide supplementary information compared
to histopathological findings.
Materials and methods Using a standard QRT-PCR assay, we examined primary tumors and 391 lymph nodes from 31 patients with completely resected colorectal
cancer.
Results Of the 31 primary tumors, 29 were positive for CK20 by QRT-PCR.
Discussion An examination of the lymph nodes from the 29 patients with CK20-positive primary tumors revealed that 35 (92.1% sensitivity)
of the 38 histopathologically positive lymph nodes and 54 (16.7%) of the 324 histopathologically negative lymph nodes were
positive by molecular analysis. CK20 expression was detected in 10 (100%) of 10 patients with a histopathologically positive
lymph node status (pN1). In 9 (47.4%) of 19 patients with negative histopathological results (pN0), we detected a CK20 mRNA
signal in at least one lymph node. Whereas eight patients with histopathologically negative lymph nodes could be upstaged
on the basis of the molecular findings, no patient would be downstaged.
Conclusion Our results suggest that QRT-PCR for CK20 is a useful tool for the quantitative detection of micrometastases in the regional
lymph nodes. We introduce a standardized procedure that integrates a molecular diagnostic technique in the clinical staging. 相似文献