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81.
The purpose of the experiment was to test the hypothesis of a systematic change in perceptual performance within a single cardiac cycle due to the activity of the baroreceptors in carotid sinus. As an index of perceptual performance the ds-parameter from signal detection theory (TSD) was used. A 1000 Hz sine tone had to be detected in a background of white noise. Each of 4 subjects received on the average 4605 noise or noise plus tone stimuli distributed over 10 experimental sessions. When comparing performance during time intervals before and after baroreceptor activity onset no significant difference was found. Also, when tracing perceptual performance over the whole cardiac cycle in steps of 66,100, and 200 msec, no systematic variation could be detected. For steps of 33 msec a rhythmic pulsation of perceptual performance of about 8 Hz appeared. An influence of electrical activity of the brain on perceptual performance was postulated. This activity would have to be time-locked to carotid sinus baroreceptor activity. 相似文献
82.
Detection and identification of fungi from fungus balls of the maxillary sinus by molecular techniques 下载免费PDF全文
Willinger B Obradovic A Selitsch B Beck-Mannagetta J Buzina W Braun H Apfalter P Hirschl AM Makristathis A Rotter M 《Journal of clinical microbiology》2003,41(2):581-585
The aim of this study was to find a reliable method for the detection and identification of fungi in fungus balls of the maxillary sinus and to evaluate the spectrum of fungi in these samples. One hundred twelve samples were obtained from patients with histologically proven fungal infections; 81 samples were paraffin-embedded tissue sections of the maxillary sinus. In 31 cases, sinus contents without paraffin embedding were sent for investigation. PCR amplification with universal fungal primers for 28S ribosomal DNA and amplicon identification by hybridization with species-specific probes for Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus glaucus, Pseudallescheria boydii, Candida albicans, and Candida glabrata were performed for all samples. Furthermore, PCR products were sequenced. Fresh samples were also cultivated. Fungal DNA was detected in all of the fresh samples but only in 71 paraffin-embedded tissue samples (87.7%). Sequence analysis was the most sensitive technique, as results could be obtained for 28 (90.3%) fresh samples by this method in comparison to 24 (77.4%) samples by hybridization and 16 (51.6%) samples by culture. However, sequence analysis delivered a result for only 36 (50.7%) of the paraffin-embedded specimens. Hybridization showed reliable results for A. fumigatus, which proved to be the most common agent in fungus balls of the maxillary sinus. Other Aspergillus species and other genera were rarely found. 相似文献
83.
84.
Depression and level of disability are evaluated in acute and chronic low back pain (LBP) patients. To assess the possibility that some somatic symptoms are confounded with pain, the items of the Beck Depression Inventory arc divided into a cognitive-affective and somatic subscale. The sample consisted of 37 chronic LBP patients. 41 acute LBP patients, and 28 healthy participants. The level of disability was assessed by the Oswestry Low Back Pain Disability Questionnaire. Chronic LBP patients, but not acute LBP patients, have more depressive symptoms than controls. Additionally, chronic LBP patients report more somatic symptoms of depression (e.g.. emo ltional and self disturbance complaints) than cognitive-affective symptoms. Finally, correlation statistics reveal significant relations between the level of disability and depression scores. Whereas chronic patients show a significant correlation between the somatic subscale and level of disability, in acute patients the cognitive-affective subscale is significantly related to the level of disability. The findings suggest careful consideration of whether somatic symptoms of depression are related to pain when using self-report measurements of depression in pain patients. The separation of cognitive-affective and somatic symptoms of depression to evaluate pain problems seems appropriate. 相似文献
85.
Summary Venezuelan equine encephalitis virus was passaged in KB cell cultures. The virus lost its mouse pathogenicity following subcutaneous inoculation during KB cell passage; the attenuated strain also produced smaller plaques than the pathogenic strain. Both strains grew to the same extent inAedes aegypti (L.) mosquitoes after intrathoracic inoculation. If any reversions to pathogenicity occur during development of the attenuated virus in mosquitoes, then the mutation frequency per duplication per particle must be smaller than 3.5×10–6. 相似文献
86.
Sabine Siegemund Nicole Schütze Marina A. Freudenberg Manfred B. Lutz Reinhard K. Straubinger Gottfried Alber 《Immunobiology》2008,212(9-10):739-750
Induction of the interleukin-12 (IL-12) cytokine family comprising IL-12, IL-23, IL-27, and IL-12p40 by intracellular pathogens is required for orchestration of cell-mediated immune responses. Macrophages (MΦ) have been shown to be a source of IL-12 following TLR4-dependent activation by Salmonella (S.). In this study another antigen-presenting cell type, the conventional dendritic cell (cDC), was analyzed and its cytokine responses compared with those of MΦ. We generated bone marrow-derived conventional dendritic cells (BMDC) and macrophages (BMMΦ) by incubating murine bone marrow cells with supernatants containing granulocyte/macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF), respectively. Stimulation of BMDC and BMMΦ with S. enterica serovar Enteritidis (SE) or LPS resulted in the release of IL-12 and IL-23 by BMDC but not by BMMΦ. Furthermore, BMDC secreted approx. 20-fold more IL-12p40 and IL-27p28 than BMMΦ. However, BMDC and BMMΦ produced similar levels of IL-10. Using BMDC originating from wild-type (wt), TLR2def and TLR4def mice, we show that in BMDC the induction of IL-12, IL-23, and IL-27p28 by SE is dependent on TLR4, whereas low-level production of p40 is also mediated by pattern recognition receptors (PRR) other than TLR4. Interestingly, LPS- and SE-provoked responses of BMDC were remarkably similar indicating that LPS is the primary danger molecule of SE. Taken together, our results point to cDC rather than MΦ as the major producers of the IL-12 family members during in vitro infection with SE. The mechanisms of recognition of SE, however, appear to be the same for cDC and MΦ 相似文献
87.
Harald Deckart Siegfried Ertl Annemarie Blottner Manfred Tautz 《European journal of nuclear medicine and molecular imaging》1987,13(8):429-431
Whole body retention measurements were performed in volunteers after i.v. injection of 99mTc-HM-PAO (Ceretec®). The organ accumulation was measured in mice and data were transferred to standard man according to ICRP. Absorbed dose calculations were made with these data by using the concept of absorbed fractions (MIRD method). In man, the whole body retention and the retention in the brain could be calculated by direct measurement, absorbed doses to the other organs could only be derived from animal data. The absorbed dose to the brain derived from human data (10.3 Gy/MBq) is greater by a factor of 2 than that derived from animal data. The highest absorbed dose was received by the thyroid (24.4 Gy/MBq), the absorbed dose to the ovaries, testes and whole body ranged from 2.8 to 4.2 Gy/MBq.Dedicated to Professor Dr. Guenter Liess on the occasion of his 65th anniversary 相似文献
88.
89.
Hanno Niess Nikolaus Börner Maximilian Muenchhoff Elham Khatamzas Manfred Stangl Alex Graf Philipp Girl Enrico Georgi Dionysios Koliogiannis Gerald Denk Michael Irlbeck Jens Werner Markus Guba 《American journal of transplantation》2021,21(4):1629-1632
To date, little is known about the duration and effectiveness of immunity as well as possible adverse late effects after an infection with SARS-CoV-2. Thus it is unclear, when and if liver transplantation can be safely offered to patients who suffered from COVID-19. Here, we report on a successful liver transplantation shortly after convalescence from COVID-19 with subsequent partial seroreversion as well as recurrence and prolonged shedding of viral RNA. 相似文献
90.
Anne Marie Thow Raphael A Lencucha Kieron Rooney Stephen Colagiuri Manfred Lenzen 《Bulletin of the World Health Organization》2021,99(1):41
ObjectiveTo estimate the impact of reduced consumption of free sugars in line with World Health Organization recommendations, on sugar farmers globally.MethodsUsing multiregion input–output analysis, we estimated the proportional impact on production volumes of a 1% reduction in free sugars consumption by the public. We extracted data on sugar production from the Food and Agriculture Organization of the United Nations database for the top 15 sugar-cane- and beet-producing countries globally, and created a custom multiregion input–output database to assess the proportions of production going to human consumption, drawing on household expenditure surveys and national input–output databases (data valid for years 2000–2015). We also considered the impact on production volumes in relation to countries’ gross domestic product.FindingsA high proportion of current sugar production from these countries goes to human consumption, and would thus be impacted by reduced consumption of sugars. The largest impacts on cane sugar production, and thus on farmers, would likely occur in Brazil, China, India and Thailand and on beet production in Belarus, Germany, Russian Federation and United States of America.ConclusionA global opportunity exists for public health leadership to bring together the health, economic, environmental and agriculture sectors to collaborate and build capacity for promotion of alternative livelihoods for sugar farmers. Lessons regarding strategy and the importance of political economy factors can be learnt from tobacco control measures. Further research to quantify the impact of reductions in sugars consumption would provide useful insights for designing policies to complement and strengthen efforts to improve diets and health. 相似文献