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31.
Catherine Guette Christian Legros Guewen Tournois Max Goyffon Marie-Louise Célérier 《Toxicon》2006,47(6):640-649
In order to establish a venom fingerprint and a peptide profile of the Lasiodora parahybana tarantula venom gland, we used conventional methods such as reversed phase liquid chromatography coupled to an electrospray-ionisation hybrid quadrupole time of flight mass spectrometer (LC/ESI-QqTOFMS), matrix-assisted laser desorption/ionization time-of-flight-MS (MALDI-TOFMS) and direct study of L. parahybana venom by nanospray-ionization QqTOFMS (nanoESI-QqTOFMS) and a new technology for the direct analysis of fresh tissues using MALDI-TOFMS. The analysis of the crude venom allowed the characterization of specific juvenile and adult biomarkers. In situ MALDI analysis of L. parahybana venom gland sections revealed different peptide expression levels all along the gland and non-processed peptide precursors, demonstrating the power of the method for the dynamic investigation of peptide evolution in the venom gland of spiders. 相似文献
32.
Christian Waydhas Dieter Nast-Kolb Steffen Ruchholtz 《European journal of trauma and emergency surgery》2007,33(2):170-175
Abstract
Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation
to detect pelvic ring fractures and to identify those with severe bleeding.
Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims
with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the
iliac wings.
Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical
instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not
be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity
of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating
blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity
97.0%, positive predictive value 38.1%, negative predictive value 99.9%).
Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic
ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most
of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture
as being the source of bleeding quite unlikely. 相似文献
33.
Mohammed E Abushaiqa Frank K Zaran David S Bach Richard T Smolarek Margo S Farber 《American journal of health-system pharmacy》2007,64(11):1170-1173
PURPOSE: Educational interventions to reduce the use of abbreviations and dosage designations that were deemed unsafe at a level 1 trauma center are described. SUMMARY: Strategies to reduce the use of unsafe abbreviations at Detroit Receiving Hospital were studied. Six abbreviations and dosage designations were deemed as unsafe by the site's medication-use and patient medical safety committees: (1) U for units, (2) microg for microgram, (3) TIW for three times a week, (4) the degree symbol for hour, (5) trailing zeros after a decimal point, and (6) the lack of leading zeros before a decimal point. Data on abbreviation use was collected starting in September 2003 by examining copies of patients' order sheets, which are sent from nursing units to the pharmacy for processing. Data were collected during three 24-hour periods each month, with 7-10 days between each period. A data collection sheet was developed to assist in documenting the number of opportunities for each unsafe abbreviation and the actual incidence of each. Educational strategies were developed and implemented starting in October 2003 to decrease the use of the unsafe abbreviations. These strategies included inservice education programs for the medical, pharmacy, and nursing staffs; laminated pocket cards; patient chart dividers; stickers; and interventions by pharmacists and nurses during medication prescribing. During the eight-month evaluation period, 20,160 orders were reviewed, representing 27,663 opportunities to use a designated unsafe abbreviation. Educational interventions successfully reduced the overall incidence of unsafe abbreviations from 19.69% to 3.31%. CONCLUSION: Educational interventions markedly reduced the use of unsafe abbreviations in medication orders over an eight-month evaluation period. 相似文献
34.
Introduction
Planning human resources for health (HRH) is a complex process for policy-makers and, as a result, many countries worldwide swing from surplus to shortage. In-depth case studies can help appraising the challenges encountered and the solutions implemented. This paper has two objectives: to identify the key challenges in HRH planning in Belgium and to formulate recommendations for an effective HRH planning, on the basis of the Belgian case study and lessons drawn from an international benchmarking. 相似文献35.
36.
Max Heiland Philipp Pohlenz Marco Blessmann Christian R Habermann Lars Oesterhelweg Philipp C Begemann Christian Schmidgunst Felix A S Blake Klaus Püschel Rainer Schmelzle Dirk Schulze 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):814-820
OBJECTIVE: The aim of this study was to evaluate soft tissue image quality of a mobile cone-beam computed tomography (CBCT) scanner with an integrated flat-panel detector. STUDY DESIGN: Eight fresh human cadavers were used in this study. For evaluation of soft tissue visualization, CBCT data sets and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) data sets were acquired. Evaluation was performed with the help of 10 defined cervical anatomical structures. RESULTS: The statistical analysis of the scoring results of 3 examiners revealed the CBCT images to be of inferior quality regarding the visualization of most of the predefined structures. Visualization without a significant difference was found regarding the demarcation of the vertebral bodies and the pyramidal cartilages, the arteriosclerosis of the carotids (compared with CT), and the laryngeal skeleton (compared with MRI). Regarding arteriosclerosis of the carotids compared with MRI, CBCT proved to be superior. CONCLUSIONS: The integration of a flat-panel detector improves soft tissue visualization using a mobile CBCT scanner. 相似文献
37.
38.
Development of the central nervous system (CNS) involves the transformation of a two-dimensional epithelial sheet of uniform ectodermal cells, the neuroectoderm, into a highly complex three-dimensional structure consisting of a huge variety of different neural cell types. Characteristic numbers of each cell type become arranged in reproducible spatial patterns, which is a prerequisite for the establishment of specific functional contacts. The fruitfly Drosophila is a suitable model to approach the mechanisms controlling the generation of cell diversity and pattern in the developing CNS, as it allows linking of gene function to individually identifiable cells. This review addresses aspects of the formation and specification of neural stem cells (neuroblasts) in Drosophila in the light of recent studies on their segmental diversification. 相似文献
39.
Dietmar Winkler Matth?us Willeit Rainer Wolf Mara Stamenkovic Johannes Tauscher Edda Pjrek Anastasios Konstantinidis Shird Schindler Christian Barnas Siegfried Kasper 《European neuropsychopharmacology》2003,13(2):129-134
The value of a long-term treatment with clonazepam in the prophylaxis of affective disorder is discussed controversially in the scientific literature. Altogether there are only a few reports on the use of this compound as a mood stabilizer, most of them describing patients suffering from bipolar affective disorder. The aim of this investigation was to evaluate clonazepam as a phase prophylactic medication in affective disorder. We conducted a retrospective chart review in 34 out-patients of our lithium clinic (15 suffering from unipolar depression, 15 from bipolar disorder, four from schizoaffective disorder), who had been treated with clonazepam as a long-term medication. Clonazepam was either given as monotherapy, or as in the case of lithium non-responders, as adjunctive therapy. Patients with unipolar depression had significantly (P=0.026) less depressive episodes after initiation of treatment with clonazepam. Patients with bipolar disorder did not benefit from this therapy. Neither manic/hypomanic phases nor depressive episodes were reduced in this group of patients. Interestingly, clonazepam also reduced affective phases in our four schizoaffective patients on a trend level. Our results indicate that patients with unipolar depression may benefit from a maintenance treatment with clonazepam. Due to methodological limitations our results need to be replicated in controlled double-blind randomized clinical trials. 相似文献
40.
Knut E Kj?rstad Dag Ole Nordhaug Christian Korvald Stig Müller Tor Steensrud Truls Myrmel 《European journal of cardio-thoracic surgery》2007,31(4):677-684
OBJECTIVE: The time constant of mechanical restitution (T((MRC))), proposed to reflect changes in calcium release and uptake, has been shown to increase in left ventricular (LV) failure, and might have a potential as an index of contractile function. However, in vivo studies of the effect on T((MRC)) of changing loading conditions in the normal and failing heart have not been reported. Consequently, in this study, we tested the hypothesis that the increase in T((MRC)) in vivo is independent of preload and afterload. METHODS: Left ventricular pressure-volume loops were assessed at baseline in eight open chest pigs using the combined pressure-volume conductance catheter technique during right atrial pacing at 120b/min. Mechanical restitution curves (MRC) were constructed during four different loading conditions in all eight animals: uninfluenced load, reduced preload (balloon catheter in v. cava inferior), increased afterload (balloon catheter in descending aorta), and increased preload combined with reduced afterload (aortocaval shunting). Acute LV failure was then induced by microembolization through the left main coronary artery, and the experimental protocol was repeated. Contractile response was defined as the maximal first derivative of pressure (dP/dt(max)), and T((MRC)) was calculated using a least square approximation algorithm. RESULTS: Hemodynamic data 30min after microembolization showed decreased mean arterial pressure (98+/-14-67+/-10mmHg, (mean+/-SD) P<0.0001) and dP/dt(max) (1482+/-193-1001+/-125mmHg/s, P=0.001). Stroke volume decreased from 30+/-5 to 20+/-5ml (P<0.0001) compared to baseline, and preload recruitable stroke work decreased from 52+/-7 to 31+/-10mmHg (P=0.002). T((MRC)) increased in all eight animals after induction of LV failure at all loading conditions. There was no difference between the different loading conditions at baseline, nor at LV heart failure, but T((MRC)) increased significantly after the induction of heart failure (ANOVA, two ways). CONCLUSIONS: We have shown that the left ventricular T((MRC)) increases after developed heart failure. The increase in T((MRC)) was independent on loading conditions and thus have a potential for a contractility index. 相似文献