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排序方式: 共有4555条查询结果,搜索用时 31 毫秒
1.
Kienbaum Peter Schaefer Maximilian S. Weibel Stephanie Schlesinger Tobias Meybohm Patrick Eberhart Leopold H. Kranke Peter 《Der Anaesthesist》2022,71(2):123-128
Die Anaesthesiologie - Auch wenn für Anästhesiologen über Jahrzehnte die Prophylaxe und Therapie postoperativer Schmerzen im Rahmen des postoperativen Patientenkomforts an vorderster... 相似文献
2.
Stephan Koter Tina U. Cohnert Korbinian B. Hindermayr Jörg Lindenmann Maximilian Brückner Wolfgang K. Oswald Georg Werkgartner Doris Wagner 《Journal of vascular surgery》2019,69(4):1227-1232
Objective
Low psoas muscle area is shown to be an indicator for worse postoperative outcome in patients undergoing vascular surgical. Additionally, it has been associated with longer durations of hospital stay in patients with cancer who undergo surgery and subsequently greater health care costs in Europe and the United States. We sought to evaluate this effect on hospital expenditure for patients undergoing vascular repair in a health care system with universal access.Methods
Skeletal muscle mass was assessed on preoperative abdominal computed tomography scans of patients undergoing open aortic aneurysm repair in a retrospective fashion. The skeletal muscle index (SMI) was used to define low muscle mass. Health care costs were obtained for all patients and the relationship between a low SMI and higher costs was explored using linear regression and cross-sectional analysis.Results
We included 156 patients (81.5% male) with a median age of 72 years undergoing elective surgery for infrarenal abdominal aortic aneurysm in this analysis. The median SMI for patients with low skeletal muscle mass was 53.21 cm2/kg and for patients without, 70.07 cm2/kg. Hospital duration of stay was 2 days longer in patients with low skeletal muscle mass as compared with patients with normal (14 days vs 11 days; P = .001), as was duration of intensive care stay (3 days vs 1 day; P = .01). The median overall hospital costs were €10,460 higher for patients with a low SMI as compared with patients with a normal physical constitution (€53,739 [interquartile range, €45,007-€62,471] vs €43,279 [interquartile range, €39,509-€47,049]; P = .001). After confounder adjustment, a low SMI was associated with a 14.68% cost increase in overall hospital costs, for a cost increase of €6521.Conclusions
Low skeletal muscle mass is independently associated with higher hospital as well as intensive care costs in patients undergoing elective aortic aneurysm repair. Strategies to reduce this risk factor are warranted for these patients. 相似文献3.
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5.
Stefan Wirth Ekkehard Euler Ulrich Linsenmaier Sandro-Michael Heining Dorothea Kotsianos Klaus-Jürgen Pfeifer Wolf Mutschler Maximilian Reiser 《Computer aided surgery》2004,9(1-2):27-38
OBJECTIVE: To analyse the image quality and diagnostic effectiveness of a new C-arm-based 3D imaging method (C-arm-CT) for intraoperative evaluation of screw osteosyntheses adjacent to a peripheral joint. MATERIALS AND METHODS: Insertion of screws into four cadaveric specimens simulated the surgical treatment of talus neck fractures. Ten orthopedic surgeons and 10 radiologists evaluated X-ray, C-arm fluoroscopy, C-arm-CT and CT images. RESULTS: The best image quality was obtained with X-rays (p < 0.001), followed by C-arm fluoroscopy (2D) and CT, with the C-arm-CT (3D) being rated lowest (p < 0.001). The most correct diagnoses were obtained with CT and C-arm-CT (with no statistical difference between them), while C-arm-fluoroscopy was inferior (p < 0.001) and X-rays were the worst (p < 0.05). CONCLUSIONS: Even if the image quality of C-arm-CT is definitely inferior to that of CT, screw misplacements can be reliably detected using C-arm-CT. As compared to the current standard procedures (intraoperative fluoroscopy and postoperative radiography), C-arm-CT performed better. C-arm-CT is ideally suited to the intraoperative diagnosis of high-contrast inquiries like bone fragments and OS material, especially at the extremities. Coupling of the new 3D imaging to existing navigation systems is possible. C-arm-CT will support the further development and implementation of open and minimally invasive surgical procedures. 相似文献
6.
K. A. Reiser 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1943,145(4):489-496
Ohne ZusammenfassungDie vorliegende Arbeit war als Vortrag für die abgesagte Tagung der Deutschen ophthalmologischen Gesellschaft angemeldet.Die Untersuchungen wurden mit Hilfe des Westdeutschen Tuberkulose-Forschungsinstitudes durchgeführt. 相似文献
7.
8.
Costimulatory molecules of the B7 family regulate the activation of T lymphocytes. T cell activation is promoted by binding of B7 molecules to CD28 and inhibited by binding to CTLA-4 (CD152). The balance between positive signals through CD28 and negative signals through CTLA-4 is critical for the fate of the T cell and is subject to tight regulation. Recent in vitro and in vivo studies have significantly advanced our understanding of the function of the CTLA-4 receptor. The results of these experiments suggest that CTLA-4 is critical for the induction of self-tolerance, and that it may have distinct signaling functions in resting and activated T cells. In resting T cells, CTLA-4 crosslinking leads to cell-cycle arrest, whereas in activated T cells, CTLA-4 crosslinking induces apoptosis. In this article, we will review the physiologic functions of the CTLA-4 receptor. 相似文献
9.
Purpose. To estimate disease activity in patients with systemic sclerosis using contrast-enhanced MRI of the skin.
Material and Methods. In a pre-study, sequences of a low-field (0.2 T) scanner (Artoscan, Esaote, Genova, Italy) were optimized for detection of
intravenous contrast (0.1 mmol/l Gd-DTPA) in six patients with the autoimmune disease systemic scleroderma. Based on the results
of the pre-study, 17 patients with scleroderma (7 sclerotic/10 active inflammatory disease) were scanned using gradient-spoiled
3D GRE sequences (FA 90 °, TR 100 ms, TE 18 ms), which had been established as most sensitive for intravenous contrast. Contrast
enhancement of the skin was determined quantitatively by contrast-to-noise ratios (CNR), comparing post- to pre-contrast and
dynamic scans (for 6 min, 1 acquisition/min). Patients in the chronic state with sclerodactylia and active inflammation of
the hands were considered separately and compared to a control group (n = 10) matched according to age.
Results. CNR increase after intravenous contrast was significantly higher in patients with active disease (86 ± 16 % increase) than
sclerosing disease (29 ± 3 %, p < 0.05) and the control group (4 ± 2 %, p < 0.05). The dynamic examination showed a significantly slower decrease after the peak rise in the first minute in patients
with active disease (CNR 15.4 ± 0.7 to 14.2 ± 1.4) than in those with chronic disease (14.1 ± 0.5 to 11.3 ± 0.9, p < 0.05).
Discussion. Capillary leakage is the most likely explanation for the increased enhancement in patients with active scleroderma. Using
sequences optimized for contrast detection, disease activity in the course of scleroderma and response to therapy can be determined
by MRI in the future.
相似文献
10.
Endothelin and a Ca2+ ionophore raise cyclic GMP levels in a neuronal cell line via formation of nitric oxide. 总被引:1,自引:1,他引:0 下载免费PDF全文
G. Reiser 《British journal of pharmacology》1990,101(3):722-726
1. The vasoconstrictor peptide endothelin-1 caused a fast, transient rise in guanosine 3':5'-cyclic monophosphate (cyclic GMP) levels in a neuronal cell line (mouse neuroblastoma x rat glioma hybrid cells 108CC15). The mechanism of activation of guanylate cyclase by endothelin-1 was investigated. The endothelin-1-induced rise depended on the release of internal Ca2+. 2. The stimulation of cyclic GMP synthesis induced by endothelin-1 was suppressed after preincubating the cells in medium containing haemoglobin (IC50 3 microM). Similarly, pretreatment of the cells with the L-arginine analogues, L-canavanine (IC50 60 microM) or NG-monomethyl-L-arginine (IC50 2.5 microM), inhibited the cyclic GMP response to endothelin-1. Therefore, endothelin-1 activates guanylate cyclase most probably via formation of nitric oxide, which is released from L-arginine. 3. The Ca2+ ionophore ionomycin induced a transient rise in cyclic GMP levels, which was also suppressed by preincubation in the presence of either haemoglobin or the L-arginine analogues L-canavanine or NG-monomethyl-L-arginine. Therefore, we conclude that ionomycin can activate guanylate cyclase by a mechanism involving nitric oxide formation, similar to that induced by endothelin-1. 4. The alkaloid veratridine, which activates Na+ channels and also causes influx of Ca2+ induced a transient rise of cyclic GMP levels in the neuronal cell line. This stimulation was blocked by pretreating the cells with L-canavanine, NG-monomethyl-L-arginine or haemoglobin. 5. Loading the cells with the Ca2+ chelator BAPTA suppresed the cyclic GMP response to application of endothelin-1, ionomycin, or veratridine.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献