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141.
Serwe S Körding KP Trommershäuser J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,210(1):67-80
Many perceptual cue combination studies have shown that humans can integrate sensory information across modalities as well
as within a modality in a manner that is close to optimal. While the limits of sensory cue integration have been extensively
studied in the context of perceptual decision tasks, the evidence obtained in the context of motor decisions provides a less
consistent picture. Here, we studied the combination of visual and haptic information in the context of human arm movement
control. We implemented a pointing task in which human subjects pointed at an invisible unknown target position whose vertical
position varied randomly across trials. In each trial, we presented a haptic and a visual cue that provided noisy information
about the target position half-way through the reach. We measured pointing accuracy as function of haptic and visual cue onset
and compared pointing performance to the predictions of a multisensory decision model. Our model accounts for pointing performance
by computing the maximum a posteriori estimate, assuming minimum variance combination of uncertain sensory cues. Synchronicity
of cue onset has previously been demonstrated to facilitate the integration of sensory information. We tested this in trials
in which visual and haptic information was presented with temporal disparity. We found that for our sensorimotor task temporal
disparity between visual and haptic cue had no effect. Sensorimotor learning appears to use all available information and
to apply the same near-optimal rules for cue combination that are used by perception. 相似文献
142.
D'Andrea MM Venturelli C Giani T Arena F Conte V Bresciani P Rumpianesi F Pantosti A Narni F Rossolini GM 《Journal of clinical microbiology》2011,49(7):2755-2758
We report on the first detection of the NDM-1 carbapenemase in Italy, in Escherichia coli isolated in October 2009. Prolonged colonization and relapsing infection by NDM-1-positive E. coli were observed in a patient (index case) with an indirect epidemiological link with areas of endemicity. Transient colonization was apparently observed in another patient linked with the index case. 相似文献
143.
Jesco Pfitzenmaier Sascha Pahernik Stephan Buse Axel Haferkamp Nenad Djakovic Markus Hohenfellner 《World journal of urology》2009,27(5):637-642
Purpose
The purpose of our study was to evaluate and compare the survival in prostate cancer (PCa) patients who underwent radical prostatectomy (RP) < and ≥70 years. 相似文献144.
Sascha A. Müller Mark Hartel Arianeb Mehrabi Thilo Welsch David J. Martin Ulf Hinz Bruno M. Schmied Markus W. Büchler 《Journal of gastrointestinal surgery》2009,13(4):784-792
Introduction
Pancreaticoduodenectomy (PD) is the standard operation for cancer of the pancreatic head. To achieve complete tumor resection and, thus, improve long-term survival, venous resection of the portal or superior mesenteric vein with reconstruction has become routine for advanced pancreatic adenocarcinoma (PDAC). However, its clinical benefit still remains controversial. The aim of this study was to investigate morbidity, mortality, and survival of patients with advanced PDAC following PD with venous resection and to identify significant survival determinants.Material and Methods
From October 2001 to December 2007, 488 patients with PDAC of the pancreatic head underwent PD at our department. Venous resection was performed in 110 patients (22.5%). Clinical data, surgical techniques, perioperative parameters, and histopathologic data were analyzed on a prospective database.Results
Major venous reconstruction was accomplished through primary lateral venorrhaphy in 18 patients (16.3%), polytetrafluoroethylene grafting (n?=?14, 12.7%), primary end-to-end anastomosis (n?=?72, 65.5%), an autologous saphenous venous graft patch (n?=?4, 4.6%) or a Goretex® patch (n?=?2, 2.3%). In 78.1% histopathologic examination revealed cancer invasion of the vein, whereas the remainder had peritumoral inflammation extending to the vessel wall. Perioperative morbidity rate was 41.8%; and the mortality rate 3.6%. The 1-, 2-, and 3-year survival rates were 55.2%, 23.1%, and 14.4%, respectively. Operating time (>420 min) and advanced age (>70 years) were the only prognostic variables, which significantly diminished survival on multivariate analysis.Conclusion
Resection of the superior mesenteric or portal vein to achieve macroscopic tumor clearance can be performed safely with acceptable operative morbidity and mortality. However, improved local clearance in these patients cannot achieve a favorable long-term survival for all patients because distant metastases or local recurrence is frequent. 相似文献145.
Christoph Reissfelder MD Nuh N. Rahbari MD Moritz Koch MD Alexis Ulrich MD Isabel Pfeilschifter Anke Waltert Sascha A. Müller MD Peter Schemmer MD Markus W. Büchler MD Jürgen Weitz MD MSc 《Annals of surgical oncology》2009,16(12):3279-3288
Background
Several prognostic scoring systems have been established for patients undergoing resection of colorectal cancer (CRC) liver metastases; however, comparative analyses of their prognostic relevance is still lacking in the literature. The aim of the present study was to assess the predictive value of five published scoring systems in an independent patient cohort for the purpose of external validation. 相似文献146.
Arianeb Mehrabi Hamidreza Fonouni Rezvan Ahmadi Bruno M. Schmied Sascha A. Müller Thilo Welsch Peter Hallscheidt Martin Zeier Jürgen Weitz Jan Schmidt 《Clinical transplantation》2009,23(3):321-328
Abstract: Using lacerated livers for liver transplantation (LTx) can add an option to the extended donor criteria. We present an LTx case using a severely lacerated liver and review of the literature for reported cases. We used a high-grade lacerated liver from a 19-yr-old brain-dead patient caused by traffic accident. The liver had grade IV and II lacerations in the right and left lobe, respectively. Lacerations were managed by sealants, stitching and perihepatic packing. The liver was transplanted to a 49-yr-old man suffering from hepatocellular carcinoma on hepatitis C-induced liver cirrhosis. The two-yr follow-up was uneventful. All published LTx cases using traumatized livers (n = 18) were analyzed. The liver injury ranged from subcapsular hematoma to deep ruptures. Most reported lacerations were in the right lobe, which were managed by digital compression, suturing, electrocautery, and perihepatic packing. The reported complications were primary non- (18%), or poor function, liver abscess, bilioma, and subhepatic hematoma each in one case (5.5%). Six-month graft and patient survival were 71% and 88%, respectively. With meticulous management lacerated livers can be transplanted successfully. Because of complexity of the management, procurement and transplantation should be done by experienced liver surgeons. These organs are marginal grafts and should be offered to selected patients. 相似文献
147.
Boesch S Sturm B Hering S Goldenberg H Poewe W Scheiber-Mojdehkar B 《Annals of neurology》2007,62(5):521-524
To determine the role of recombinant human erythropoietin as a possible treatment option in Friedreich's ataxia, we performed an open-label clinical pilot study. Primary outcome measure was the change of frataxin levels at week 8 versus baseline. Twelve Friedreich's ataxia patients received 5,000 units recombinant human erythropoietin three times weekly subcutaneously. Frataxin levels were measured in isolated lymphocytes by enzyme-linked immunosorbent assay. In addition, urinary 8-hydroxydeoxyguanosine and serum peroxides, were measured. Treatment with recombinant human erythropoietin showed a persistent and significant increase in frataxin levels after 8 weeks (p < 0.01). All patients showed a reduction of oxidative stress markers. 相似文献
148.
Sciarretta S Ferrucci A Ciavarella GM De Paolis P Venturelli V Tocci G De Biase L Rubattu S Volpe M 《American journal of hypertension》2007,20(7):784-791
BACKGROUND: Previous studies have shown that metabolic syndrome (MS) is associated with an increased susceptibility to develop cardiovascular damage (CD). Experimental evidence indicates that inflammation and fibrosis could play a critical role in the development of CD in hypertension. This issue has not been clarified yet in patients with MS. The aim of our study was to investigate the relationship between markers of inflammation and fibrosis with CD in hypertensive patients with and without MS. METHODS: One hundred twenty-eight essential hypertensive patients were included in the study: 51 with MS and 77 without MS. Clinical, biochemical parameters, 24-h urinary albumin excretion rate (UAER), levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), and procollagen type 1 carboxy-terminal propeptide (PICP) were measured. All patients underwent an echocardiographic examination with transmitral Doppler and tissue Doppler imaging (TDI). RESULTS: Left ventricular mass indexed by height(2.7) (LVM/h(2.7)) (P < .001), early diastolic peak flow velocity/early myocardial diastolic velocity ratio (E/Em ratio), a TDI index of diastolic function (P < .001), and 24-h UAER (P < .05) were significantly higher in the group with MS, whereas peak myocardial systolic velocity (Sm), a TDI index of systolic function (P < .001), was lower. Serum levels of CRP (P < .001), TNF-alpha (P < .05), TGF-beta (P < .01), and PICP (P < .001) were significantly increased in MS. These markers were significantly related to higher LVMI(2.7), higher E/Em ratio, and increased 24-h UAER and a lower Sm in the whole population, with a further significant enhancement in MS. CONCLUSIONS: Cardiovascular damage is more frequent in hypertensives with MS than in hypertensives without MS, and this is significantly related to the increased levels of inflammation and fibrosis found in hypertensives with MS. 相似文献
149.
Exclusion of patients with arteriosclerosis reduces long-term recurrence rate of presumed arterial embolism after PFO closure 总被引:1,自引:1,他引:0
Dubiel M Bruch L Liebner M Schmehl I Winkelmann A Rux S Sonntag S Wulff H Grad MO Kleber FX 《Journal of interventional cardiology》2007,20(4):275-281
BACKGROUND: Percutaneous transcatheter closure of patent interatrial communications after presumed paradoxical embolism is used as an alternative to surgery or long-term anticoagulation for the treatment of patients who are at risk for recurrent thromboembolism. To avoid atherosclerotic events to be judged as recurrent paradoxical embolism, we prospectively excluded all patients with detectable arteriosclerosis from our series and investigated long-term results. METHODS AND RESULTS: We report the outcome of 180 patients who underwent percutaneous transcatheter closure of patent foramen ovale (PFO), PFO like atrial septal defect (ASD), or an ASD because of paradoxical embolism. One hundred four patients had cerebral embolism, 57 had transient ischemic attacks, 16 coronary embolism, and 3 had peripheral embolism. Twenty-three patients experienced multilocal arterial embolism. One hundred twenty-five patients had a PFO, 63 of them with an atrial septal aneurysm (ASA), 24 a PFO-like ASD (7 of them with an ASA), and 31 had an ASD. After 18 months, only 5 patients (2.8%) showed a trivial residual shunt. At a mean follow-up of 40 months (range 4 to 88), resulting in 602 observed patient-years, only 1 patient experienced a presumed paradoxical (coronary) embolism (calculated annual risk to suffer a recurrent thromboembolic event: 0.16%). CONCLUSIONS: Percutaneous transcatheter closure of PFO/ASD is a safe and effective therapeutic option for the secondary prevention of presumed paradoxical embolism. It is associated with a high success rate, low incidence of hospital complications, and very low frequency of recurrent systemic embolic events. 相似文献
150.
Djordjevic A Veljkovic M Antoni S Sakarellos-Daitsiotis M Krikorian D Zevgiti S Dietrich U Veljkovic N Branch DR 《Current HIV research》2007,5(5):443-448
The C-terminus of the second conserved region of HIV-1 gp120 represents a functionally important domain, as it encompasses amino acids directly involved in the binding to the CD4 receptor and in post-receptor binding events. Previous studies have suggested that antibodies with specific affinity to a 23 amino acids-long NTM polypeptide, derived from this HIV-1 gp120 domain, may be involved in the control of HIV disease progression. In the current work, we searched for NTM-recognizing antibodies in specific cohorts of HIV-1 infected individuals, including long-term nonprogressors (LTNP) and progressors. For this purpose, we employed a previously defined bioinformatics criterion for design of an NTM peptide mimetic to select an octapeptide, NTMs (FTDNAKTI), which is more suitable for use in a solid-state enzyme-linked immunosorbent assay (ELISA). Our results show that NTMs-reactive antibodies are significantly more prevalent (p < 0.01) in LTNP as compared to progressors and healthy control subjects, indicating their association with non-progressive infection. The presence of antibodies recognizing the second conserved region of the HIV-1 gp120 derived peptide, NTMs, in LTNP sera suggest that these antibodies could be of considerable interest for development of anti-HIV immune-based therapies and vaccines. 相似文献