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11.
The objective of the study was to evaluate the role of autologous blood transfusion in current clinical practice in the Federal Republic of Germany after reunification. METHODS: Questionnaires were sent to the anaesthesia departments of 684 German hospitals in January 1993. The sample consisted of 400 randomly selected hospitals from the former West Germany ("old federal states") and 284 hospitals from the former German Democratic Republic ("new federal states"). Only hospitals with more than 25 surgical beds were included in the study. The questionnaire contained 36 questions related to (1) general information on the hospital, (2) preoperative autologous blood donation (PABD), (3) preoperative plasmapheresis, (4) isovolaemic haemodilution, (5) perioperative blood salvage, and (6) general management of blood transfusion. RESULTS: A total of 502 completed questionnaires (73%) were returned, 305 from hospitals in the "old federal states" and 197 from hospitals in the former German Democratic Republic. Nine per cent of the responding hospitals were running their own transfusion services, and 56% were located in the vicinity of a regional blood bank. The overall proportion of surgical procedures requiring perioperative blood transfusion ranged from 1% to 90% (median 10%). PABD was performed "not at all" in 18%, "rarely" in 20% "occasionally" in 27%, "frequently" in 17%, and "mostly" in 16% of the responding hospitals. The principal use of PABD was in orthopaedic surgery and cardiac surgery (83% and 70% of the departments in question, respectively). In more than 50% of the hospitals reporting, the PABD service was run by the anaesthesia department. Patients not meeting the established criteria for homologous blood donors were accepted for autologous blood donation "frequently" and "mostly" in 20% and 12% of the hospitals, respectively, but at most "occasionally" in 63% of the hospitals. Preoperative plasmapheresis was performed in 12% of the responding hospitals. Autologous fresh frozen plasma predominantly was used for volume replacement, and for prevention of coagulation disorders when major blood loss was anticipated. Isovolaemic haemodilution was performed "not at all" in 28%, "rarely" in 19%, "occasionally" in 28%, "frequently" in 16%, and "mostly" in 8% of the responding hospitals. The reasons most frequently invoked for not performing haemodilution were "too time consuming" and "too little blood-saving effect". Cell separators for perioperative blood salvage were available in 30% of the responding hospitals. Of the other hospitals not equipped with cell-washing devices, 11% performed perioperative blood salvage of unprocessed blood by means of simple collection devices. Some 80% of those hospitals using intraoperative autotransfusion devices also performed blood salvage postoperatively. The principal use of perioperative blood salvage was in cardiac surgery, orthopaedics, and vascular surgery (90%, 54%, and 54% of departments, respectively). Some 48% of the responding anaesthetists "mostly" considered haemoglobin levels of 8-10 g/dl acceptable in patients without cardiopulmonary disease, but only 18% did so in patients with cardiopulmonary disease. CONCLUSIONS: Although available in the majority of hospitals surveyed, the simple techniques of both PABD and isovolaemic haemodilution are unduly neglected in routine clinical practice. The consistent use of both of these techniques, and the careful weighing up of the indication for every single blood transfusion, would not only effectively reduce homologous blood transfusions, but also enable even small hospitals to run successful autologous transfusion programmes without expensive cell-washing and plasmapheresis devices. 相似文献
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A novel approach of combining flexible molecular docking, GRID molecular interaction fields, analysis of ligand-protein hydrogen bond interactions, conformational energy penalties and 3D-QSAR analysis was used to propose a binding mode in the dimer interface of the iGluR2 receptor for the biarylpropylsulfonamide class of positive allosteric AMPA modulators. Possible binding poses were generated by flexible molecular docking. GRID molecular interaction fields of the binding site, ligand-protein hydrogen bonding interactions and conformational energy penalties were used to select the most likely binding mode. The selected binding poses were subjected to a 3D-QSAR analysis using previously published activity data. The resulting model (2 LVs, R2=0.89, q2=0.61) predicted the activities of the compounds in the test set with a standard deviation on error of prediction of 0.17. The proposed binding mode was validated by interpretation of the PLS-coefficient regions from the 3D-QSAR analysis in terms of interactions between the receptor and the modulators. 相似文献
14.
Rasmussen CD Jørgensen MB Carneiro IG Flyvholm MA Olesen K Søgaard K Holtermann A 《Ergonomics》2012,55(2):256-264
Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group. 相似文献
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Yilin Tian Caleb Arata Erin Boedicker David M. Lunderberg Sameer Patel Sumit Sankhyan Kasper Kristensen Pawel K. Misztal Delphine K. Farmer Marina Vance Atila Novoselac William W. Nazaroff Allen H. Goldstein 《Indoor air》2021,31(1):88-98
Inhalation of particulate matter is associated with adverse health outcomes. The fluorescent portion of supermicron particulate matter has been used as a proxy for bioaerosols. The sources and emission rates of fluorescent particles in residential environments are not well-understood. Using an ultraviolet aerodynamic particle sizer (UVAPS), emissions of total and fluorescent supermicron particles from common human activities were investigated during the HOMEChem campaign, a test-house investigation of the chemistry of indoor environments. Human occupancy and activities, including cooking and mopping, were found to be considerable sources of indoor supermicron fluorescent particles, which enhanced the indoor particle concentrations by two orders of magnitude above baseline levels. The estimated total (fluorescent) mass emission rates for the activities tested were in the range of 4-30 (1-11) mg per person meal for cooking and 0.1-4.9 (0.05-4.7) mg/h for occupancy and mopping. Model calculations indicate that, once released, the dominant fate of coarse particles (2.5-10 micrometer in diameter) was deposition onto indoor surfaces, allowing for the possibility of subsequent resuspension and consequent exposures over durations much longer than the ventilation time scale. Indoor coarse particle deposition would also contribute to soiling of indoor surfaces. 相似文献
17.
Dr. Kasper K. Sørensen Dr. Jens B. Simonsen Dr. Nicolai N. Maolanon Prof. Jens Stougaard Prof. Knud J. Jensen 《Chembiochem : a European journal of chemical biology》2014,15(14):2097-2105
Recognition of carbohydrates by proteins is a ubiquitous biochemical process. In legume–rhizobium symbiosis, lipochitin oligosaccharides, also referred to as nodulation (nod) factors, function as primary rhizobial signal molecules to trigger root nodule development. Perception of these signal molecules is receptor mediated, and nod factor receptor 5 (NFR5) from the model legume Lotus japonicus is predicted to contain three LysM domain binding sites. Here we studied the interactions between nod factor and each of the three NFR5 LysM domains, which were chemically synthesized. LysM domain variants (up to 58 amino acids) designed to optimize solubility were chemically assembled by solid‐phase peptide synthesis (SPPS) with microwave heating. Their interaction with nod factors and chitin oligosaccharides was studied by isothermal titration calorimetry and circular dichroism (CD) spectroscopy. LysM2 showed a change in folding upon nod factor binding, thus providing direct evidence that the LysM domain of NFR5 recognizes lipochitin oligosaccharides. These results clearly show that the L. japonicus LysM2 domain binds to the nod factor from Mesorhizobium loti, thereby causing a conformational change in the LysM2 domain. The preferential affinity for nod factors over chitin oligosaccharides was demonstrated by a newly developed glycan microarray. Besides the biological implications, our approach shows that carbohydrate binding to a small protein domain can be detected by CD spectroscopy. 相似文献
18.
Back Cover: Mapping the Interactions of Selective Biochemical Probes of Antibody Conformation by Hydrogen–Deuterium Exchange Mass Spectrometry (ChemBioChem 11/2017)
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19.
An instructional approach is presented to improve human performance in solving Bayesian inference problems. Starting from the original text of the classic Mammography Problem, the textual expression is modified and visualizations are added according to Mayer’s principles of instruction. These principles concern coherence, personalization, signaling, segmenting, multimedia, spatial contiguity, and pretraining. Principles of self-explanation and interactivity are also applied. Four experiments on the Mammography Problem showed that these principles help participants answer the questions at significantly improved rates. Nonetheless, in novel interactivity conditions, performance was lowered suggesting that more interaction can add more difficulty for participants. Overall, a leap forward in accuracy was found, with more than twice the participant accuracy of previous work. This indicates that an instructional approach to improving human performance in Bayesian inference is a promising direction. 相似文献
20.
The aim of this study was to determine the effect of a carotenoid mixture (Capsantal FS-30-NT), containing capsanthin and capsorubin, on growth and aflatoxins (AF) production of AF-producing Aspergillus flavus isolates. 相似文献