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11.
Journal of Public Health - Offshore wind energy is a fast growing market. Accordingly, a correspondingly large number of employees are working at the wind farms. Owing to the harsh operating...  相似文献   
12.
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   
13.
Many acute and chronic liver diseases are often associated with atypical ductular proliferation (ADP). These ADPs have gained increasing interest since a number of recent observations suggest that ADPs may represent progenies of the putative liver stem cell compartment. In this study, we show that feeding mice with 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) results in persistent proliferation of primitive ductules with poorly defined lumens. Similar to oval cell proliferation in other rodent models as well as in various human liver diseases, DDC-induced ADP originated from the portal tract, spread into the hepatic lobule, and was associated closely with appearance of hepatocytes harboring an antigen (A6), which normally is expressed in biliary epithelium. Furthermore, DDC treatment severely inhibited the regenerative capacity of mice after partial hepatectomy. The development of ADP was selectively blocked in DDC-fed TGF-beta1 transgenic mice producing active TGF-beta1 in the liver and no accumulation of new hepatocytes expressing the A6 antigen was observed. Moreover, the transforming growth factor beta1 (TGF-beta1) transgenic mice did not survive beyond 3 weeks from starting the DDC-containing diet. The results suggest that persistent activation of the hepatic stem cell compartment is essential for liver regeneration in the DDC model and that active TGF-beta1 may negatively control activation of stem cells in the liver. These data further emphasize the relevance of the DDC model as an experimental tool for studying chronic liver diseases.  相似文献   
14.
Male and female Sprague-Dawley rats, 4–6 days old were exposed for 3 weeks (6 h/day, 5 days/week) to 2-nitropropane vapours of 0, 25, 40, 50, 80 and 125 ppm. One week later polychlorinated biphenyls (Clophen A50, 10 mg/kg body weight) were administered for promotion twice a week for 8 weeks. Thirteen weeks after starting the experiments the logarithms of the numbers of preneoplastic liver foci deficient in adenosine-5-triphosphatase were found to be linearly related to the exposure concentrations of 2-nitropropane. Male rats exhibited an approximately four times lower foci incidence than females.  相似文献   
15.
In a series of robberies, 11 elderly women living alone were attacked by an assailant (HS) by means of chop blows directed primarily at the throat, but also at the head, neck, and thorax. 5 died of their injuries. 1 died immediately after the assault. The other 4 victims survived for between 7-38 days. As a result of the injuries incurred, the women were confused, physically weakened and confined to bed, and eventually died from pneumonia. Their death was thus casually related to the violence sustained. Extensive haematomas of the scalp and cervical soft tissue were present. In 3 cases there were injuries to the laryngeal skeleton and adjacent soft tissue. In 2 cases there were conjunctival haemorrhages. The other 6 attacks were not fatal. The blows led to transient unconsciousness, which often resulted in a state of confusion, sometimes mimicking cerebrovascular accidents (CVA). Of other injuries, craniofacial haematomas were the most common. These cases are reviewed in this paper.  相似文献   
16.
AIM: Videofluoroscopic assessment of the spectrum and incidence of swallowing complications after state-of-the-art laryngeal cancer surgery. MATERIALS AND METHODS: We retrospectively studied videofluoroscopic examinations of 120 patients (94 men, 26 women; mean age, 58 years) with suspected complications after laryngeal resection (partial laryngectomy, 65; total laryngectomy, 55). Swallowing function (i.e., oral bolus control, laryngeal elevation and closure, presence of pharyngeal residue, aspiration) and structural abnormalities such as strictures, fistulas and tumour recurrence were assessed by videofluoroscopy. RESULTS: Abnormalities were found in 110 patients, including strictures in nine, fistulas in six and mass lesions in 13 patients. Aspiration was found in 63 patients overall (partial laryngectomy, 61/65; total laryngectomy, 2/55), occurring before swallowing in five, during swallowing in 34, after swallowing in nine and at more than one phase in 15 patients. Pharyngeal paresis was detected in three and pharyngeal weakness in 19 patients. Pharyngo-oesophageal sphincter dysfunction was observed in 10 cases. CONCLUSION: Aspiration is a very common complication after partial laryngeal resection. It is mainly caused by incomplete laryngeal closure, sphincter dysfunction or pharyngeal pooling. Videofluoroscopy is the only radiological technique able to identify both disordered swallowing function and structural changes after laryngeal resection. Detection of these complications is crucial for appropriate further therapy.Kreuzer, S. H. (2000). Clinical Radiology55, 775-781.  相似文献   
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18.
Incidents with toxic benthic cyanobacteria blooms have been increasing recently. In 2019, several dogs were poisoned in the river Lech (Germany) by the benthic anatoxin-a-producing genus Tychonema. To characterize spatial and temporal distribution of potentially toxic Tychonema in this river, a systematic monitoring was carried out in 2020, focusing on the occurrence of the genus, its toxin production and habitat requirements. Tychonema and cyanobacterial community composition in benthic mats and pelagic samples were identified using a combined approach of microscopy and DNA sequencing of the 16S rRNA gene. In addition, anatoxin-a concentrations of selected samples were measured using the ELISA method. The habitat was characterized to assess the ecological requirements and growth conditions of Tychonema. Tychonema mats and anatoxin-a were detected at several sampling sites throughout the entire study period. Toxin concentrations increased with the progression of the vegetation period and with flow direction, reaching values between 0 and 220.5 µg/L. Community composition differed among pelagic and benthic samples, with life zone and substrate condition being the most important factors. The results of this study highlight the importance of monitoring and understanding the factors determining occurrence and toxin production of both pelagic and benthic cyanobacteria due to their relevance for the health of humans and aquatic ecosystems.  相似文献   
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20.
Background: Although platelet-derived growth factor (PDGF) has been thought to be critical in the wound-healing response of Tenon's capsule fibroblasts after glaucoma filtration surgery, no information is currently available concerning the proliferative effect of PDGF isoforms on this cell type. The aim of the present study was to evaluate the proliferative effect of PDGF-AB heterodimer and PDGF-AA and -BB homodimers on cultured human Tenon's capsule fibroblasts. Methods: Human Tenon's capsule fibroblasts, cultured under serum-free conditions, were stimulated with PDGF-AA, -AB and -BB isoforms in concentrations ranging from 1 to 100 ng/ml. Cell numbers were determined on days 1, 3, 5 and 7, using a cell counter. Results: Addition of PDGF-AB and -BB led to a dosedependent increase in cell proliferation. A maximal response (79.9% over control) was obtained after 7 days with 30 ng/ml of PDGF-BB, with an EC50 of 8.9 ng/ml. The maximal increase in cell proliferation caused by PDGF-AB (30 ng/ml) was 54.9%, with an EC50 of 12.5 ng/ml. Stimulation with PDGF-AA revealed a significant effect only with concentrations higher than 30 ng/ml. Conclusion: Our results indicate that PDGF-AB and -BB isoforms are potent stimulators of proliferation of human Tenon's capsule fibroblasts, suggesting that PDGF-AB and -BB isoforms play an important role in the wound-healing response after glaucoma filtration surgery.Presented in part at the annual meeting of the Deutsche Ophthalmologische Gesellschaft, Mannheim, September 1996  相似文献   
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