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31.

Background

The study was a collaboration between Lifting The Burden (LTB) and the European Headache Federation (EHF). Its aim was to evaluate the implementation of quality indicators for headache care Europe-wide in specialist headache centres (level-3 according to the EHF/LTB standard).

Methods

Employing previously-developed instruments in 14 such centres, we made enquiries, in each, of health-care providers (doctors, nurses, psychologists, physiotherapists) and 50 patients, and analysed the medical records of 50 other patients. Enquiries were in 9 domains: diagnostic accuracy, individualized management, referral pathways, patient’s education and reassurance, convenience and comfort, patient’s satisfaction, equity and efficiency of the headache care, outcome assessment and safety.

Results

Our study showed that highly experienced headache centres treated their patients in general very well. The centres were content with their work and their patients were content with their treatment. Including disability and quality-of-life evaluations in clinical assessments, and protocols regarding safety, proved problematic: better standards for these are needed. Some centres had problems with follow-up: many specialised centres operated in one-touch systems, without possibility of controlling long-term management or the success of treatments dependent on this.

Conclusions

This first Europe-wide quality study showed that the quality indicators were workable in specialist care. They demonstrated common trends, producing evidence of what is majority practice. They also uncovered deficits that might be remedied in order to improve quality. They offer the means of setting benchmarks against which service quality may be judged. The next step is to take the evaluation process into non-specialist care (EHF/LTB levels 1 and 2).
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High-resolution elastographic assessment of the cornea can greatly assist clinical diagnosis and treatment of various ocular diseases. Here, we report on the first noncontact depth-resolved micro-scale optical coherence elastography of the cornea achieved using shear wave imaging optical coherence tomography (SWI-OCT) combined with the spectral analysis of the corneal Lamb wave propagation. This imaging method relies on a focused air-puff device to load the cornea with highly-localized low-pressure short-duration air stream and applies phase-resolved OCT detection to capture the low-amplitude deformation with nano-scale sensitivity. The SWI-OCT system is used here to image the corneal Lamb wave propagation with the frame rate the same as the OCT A-line acquisition speed. Based on the spectral analysis of the corneal temporal deformation profiles, the phase velocity of the Lamb wave is obtained at different depths for the major frequency components, which shows the depthwise distribution of the corneal stiffness related to its structural features. Our pilot experiments on ex vivo rabbit eyes demonstrate the feasibility of this method in depth-resolved micro-scale elastography of the cornea. The assessment of the Lamb wave dispersion is also presented, suggesting the potential for the quantitative measurement of corneal viscoelasticity.OCIS codes: (170.4460) Ophthalmic optics and devices, (170.4500) Optical coherence tomography, (120.5050) Phase measurement  相似文献   
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Research on radioactive contamination of the environment involves the important task of assessing the contribution from different sources of contamination. If there are two or more sources of contamination with similar radionuclide composition, assessment of the contribution from each source can be challenging. Such a problem exists, for instance, in the assessment of anthropogenic sources of radioactive contamination of water in the Techa River. At the present time, the main contaminating radionuclides for the Techa River are 90Sr, 137Cs, and 3H. In 2009-2010, the content of radionuclides in the water of the river was 90Sr-3.8-32.9 Bq L, 137Cs-0.02-2.43 Bq L, and 3H-31.0-263.2 Bq L. This work gives a qualitative assessment of the role of different contamination sources in the formation of volumetric activity of Sr in the water of the Techa River. Also, the behavior of anthropogenic radionuclides in the open fluvial river system is reviewed.  相似文献   
35.
The ability of terrestrial microorganisms to grow in the near-surface environment of Mars is of importance to the search for life and protection of that planet from forward contamination by human and robotic exploration. Because most water on present-day Mars is frozen in the regolith, permafrosts are considered to be terrestrial analogs of the martian subsurface environment. Six bacterial isolates were obtained from a permafrost borehole in northeastern Siberia capable of growth under conditions of low temperature (0 °C), low pressure (7 mbar), and a CO2-enriched anoxic atmosphere. By 16S ribosomal DNA analysis, all six permafrost isolates were identified as species of the genus Carnobacterium, most closely related to C. inhibens (five isolates) and C. viridans (one isolate). Quantitative growth assays demonstrated that the six permafrost isolates, as well as nine type species of Carnobacterium (C. alterfunditum, C. divergens, C. funditum, C. gallinarum, C. inhibens, C. maltaromaticum, C. mobile, C. pleistocenium, and C. viridans) were all capable of growth under cold, low-pressure, anoxic conditions, thus extending the low-pressure extreme at which life can function.  相似文献   
36.
Structural bone allografts often fracture due to their lack of osteogenic and remodeling potential. To overcome these limitations, we utilized allografts coated with recombinant adeno-associated virus (rAAV) that mediate in vivo gene transfer. Using beta-galactosidase as a reporter gene, we show that 4-mm murine femoral allografts coated with rAAV-LacZ are capable of transducing adjacent inflammatory cells and osteoblasts in the fracture callus following transplantation. While this LacZ vector had no effect on allograft healing, bone morphogenetic protein signals delivered via rAAV-caAlk2 coating induced endochondral bone formation directly on the cortical surface of the allograft by day 14. By day 28 there was evidence of remodeling of the new woven bone and massive osteoclastic resorption of the cortical surface of the rAAV-caAlk2-coated allografts only. Micro-CT analysis of rAAV-LacZ- vs rAAV-caAlk2-coated allografts after 42 days of healing demonstrated a significant increase in new bone formation (0.67 +/- 0.21 vs 2.49 +/- 0.40 mm(3); P < 0.005). Furthermore, the 3D micro-CT images of femurs grafted with rAAV-Alk2-coated allografts provided the first evidence that complete bridging of bone around a cortical allograft is possible. These results indicate that cell-free, rAAV-coated allografts have the potential to revitalize in vivo following transplantation.  相似文献   
37.
A novel polypeptide, designated omega-Lsp-IA, which modulates P-type Ca(2+) channels, was purified from the venom of the spider Geolycosa sp. omega-Lsp-IA contains 47 amino acid residues and 4 intramolecular disulfide bridges. It belongs to a group of spider toxins affecting Ca(2+) channels and presumably forms the inhibitor cystine knot (ICK) fold. Peculiar structural features (a cluster of positively charged residues in the C-terminal loop of the peptide and a regular distribution of hydrophobic residues) that may play a decisive role in the omega-Lsp-IA mechanism of action were located. Recombinant omega-Lsp-IA was produced in prokaryotic expression system and was shown to be structurally and functionally identical to the native toxin. At saturating concentration (10nM), the peptide clearly slows down the activation kinetics and partially inhibits the amplitude of P-current in rat cerebellar Purkinje neurons. Prominent deceleration of the activation kinetics is manifested as the appearance of a five-fold slower component of the current activation. The specificity of action of omega-Lsp-IA on different Ca(2+) channel types was studied in isolated hippocampal neurons of rat. omega-Agatoxin IVA completely removed the effect of omega-Lsp-IA on the whole-cell Ca(2+) current. Therefore, omega-Lsp-IA appears to act specifically on P-type Ca(2+) channels.  相似文献   
38.
Background: Vocal cord injuries, postoperative hoarseness, and sore throat are common complications after general anesthesia. One-lung ventilation can be achieved via two techniques: double-lumen endotracheal tube or endobronchial blocker such as the Arndt blocker. The current study was designed to assess the impact of these techniques for one-lung ventilation on the incidence and severity of postoperative hoarseness, vocal cord lesions, and sore throat.

Methods: In this prospective trial, 60 patients were randomly assigned to two groups. One-lung ventilation was achieved with either an endobronchial blocker (blocker group) or a double-lumen-tube (double-lumen group). Postoperative hoarseness and sore throat were assessed at 24, 48, and 72 h after surgery. Bronchial injuries and vocal cord lesions were examined by bronchoscopy immediately after surgery.

Results: In 56 included patients, postoperative hoarseness occurred significantly more frequently in the double-lumen group compared with the blocker group: 44% versus 17%, respectively (P = 0.046). Similar findings were observed for vocal cord lesions: 44% versus 17%, respectively (P = 0.046). The incidence of bronchial injuries was comparable between groups (P = 0.540). Cumulative number of days with hoarseness and sore throat were significantly increased in the double-lumen group compared with the blocker group (P < 0.01). No major complications such as bronchial ruptures were observed.  相似文献   

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