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61.
Landgraf H 《Hamostaseologie》2006,26(3):239-44; quiz 245-6
Platelet inhibitors and anticoagulants are used in the longterm treatment after successful infrainguinal bypass grafts as well as endovascular revascularisation procedures. However, evidence of the usefulness of these therapies is limited with respect to efficiency (patency rate, mortality) and safety (bleeding tendency) concerning these indications. Sufficient data are only available for acetylsalicylic acid treatment after implantation of prosthetic bypass grafts, the data basis for the use of antithrombotic medication in venous bypass grafts or following successful balloon angioplasty with or without stent implantation is, however, inconclusive. The recommendation for lifelong therapy with acetylsalicylic acid after infrainguinal bypass surgery and endovascular treatment is based mainly on the concept of prophylactic treatment of manifest atherosclerotic disease.  相似文献   
62.
Several international guidelines for treatment and prophylaxis of glucocorticoid-induced osteoporosis (GIO) have been published. Consistent with the development of new therapeutic agents, a different approach to treatment can be recognized depending on the year of publication. Also, new insights for the postmenopausal osteoporosis leave their marks on recent guidelines. The working committee on Osteology of the Austrian Society for Rheumatology and Rehabilitation (?GR) sifted through actual guidelines and recent literature on the topic to develop recommendations for the prophylaxis and treatment of the GIO.  相似文献   
63.
OBJECTIVE: To examine the effect of full implementation of advanced skills by ambulance personnel on the outcome from out of hospital cardiac arrest. SETTING: Patients with cardiac arrest treated at the accident and emergency department of the Royal Infirmary of Edinburgh. METHODS: All cardiorespiratory arrests occurring in the community were studied over a one year period. For patients arresting before the arrival of an ambulance crew, outcome of 92 patients treated by emergency medical technicians equipped with defibrillators was compared with that of 155 treated by paramedic crews. The proportions of patients whose arrest was witnessed by lay persons and those that had bystander cardiopulmonary resuscitation (CPR) were similar in both groups. RESULTS: There was no difference in the presenting rhythm between the two groups. Eight of the 92 patients (8.7%) treated by technicians survived to discharge compared with eight of 155 (5.2%) treated by paramedics (NS). Of those in ventricular fibrillation or pulseless ventricular tachycardia, eight of 43 (18.6%) in the technician group and seven of 80 (8.8%) in the paramedic group survived to hospital discharge (NS). For patients arresting in the presence of an ambulance crew, four of 13 patients treated by technicians compared with seven of 15 by paramedics survived to hospital discharge. Only two patients surviving to hospital discharge received drug treatment before the return of spontaneous circulation. CONCLUSIONS: No improvement in survival was demonstrated with more advanced prehospital care.  相似文献   
64.
Visual scenes are frequently composed of objects that move in different directions. To segment such scenes into distinct objects or image planes, local motion cues have to be evaluated and integrated according to criteria of global coherence. When several populations of coherently moving random dots penetrate each other, the visual system tends to assign them to different planes-perceived as transparent motion. This process of integration was studied by changing the angle of motion trajectories with which groups of dots penetrate each other or by varying the spatial constellation of dots moving in opponent directions. Psychophysical testing revealed that stimuli providing almost identical local motion cues could be perceived in three very different ways: (1) as a matrix of stationary flickering dots, (2) as a single surface of coherently moving dots, and (3) as two transparent dot matrices moving in different directions. Behaviorally controlled functional magnetic resonance imaging (fMRI) was used to identify brain regions that contribute to the integration of local motion cues into coherently moving surfaces. Activation of the human motion complex (hMT+/V5) and of areas in the fusiform gyrus (FG) as well as in the intraparietal sulcus (IPS-occ) was correlated with the perception of coherent motion and especially hMT+/V5 took a central role in differentiating transparent motion from single-surface coherent motion.  相似文献   
65.
Two regions in the human occipito-temporal cortex respond preferentially to faces: 'the fusiform face area' ('FFA') and the 'occipital face area' ('OFA'). Whether these areas have a dominant or exclusive role in face perception, or if sub-maximal responses in other visual areas such as the lateral occipital complex (LOC) are also involved, is currently debated. To shed light on this issue, we tested normal participants and PS, a well-known brain-damaged patient presenting a face-selective perception deficit (prosopagnosia) [Rossion, B., Caldara, R., Seghier, M., Schuller, A. M., Lazeyras, F., Mayer, E. (2003). A network of occipito-temporal face-sensitive areas besides the right middle fusiform gyrus is necessary for normal face processing. Brain 126 2381-2395.], with functional magnetic resonance imaging (fMRI). Of particular interest, the right hemisphere lesion of the patient PS encompasses the 'OFA' but preserves the 'FFA' and LOC [Sorger, B., Goebel, R., Schiltz, C., Rossion, B. (2007). Understanding the functional neuroanatomy of acquired prosopagnosia. NeuroImage 35, 836-852.]. Using fMRI-adaptation, we found a dissociation between the coding of individual exemplars in the structurally intact 'FFA', which was impaired for faces but preserved for objects in the patient PS's brain. Most importantly, a larger response to different faces than repeated faces was found in the ventral part of the LOC both for normals and the patient, next to the right hemisphere lesion. Thus, following prosopagnosia, areas that do not respond preferentially to faces such as the ventral part of the LOC (vLOC) may still be recruited for compensatory or residual individual face perception. Overall, these observations indicate that several high-level visual areas in the human brain contribute to individual face perception. However, a subset of these areas in the right hemisphere, those responding preferentially to faces ('FFA' and 'OFA'), appear to be critical for this function.  相似文献   
66.
Burkholderia is highly resistant to human Beta-defensin 3   总被引:9,自引:0,他引:9       下载免费PDF全文
The bactericidal activity of the novel beta-defensin hBD-3 against 28 species and 55 strains of gram-positive cocci and gram-negative fermentative and nonfermentative rods was tested. All strains proved to be highly or intermediately susceptible to hBD-3 (minimal bactericidal concentration [MBC], 100 micro g/ml.  相似文献   
67.
Laminopathies are a group of disorders caused by mutations in the LMNA gene that encodes the nuclear lamina proteins, lamin A and lamin C; their pathophysiological basis is unknown. We report that lamin A/C-deficient (Lmna(-/-)) mice develop rapidly progressive dilated cardiomyopathy (DCM) characterized by left ventricular (LV) dilation and reduced systolic contraction. Isolated Lmna(-/-) myocytes show reduced shortening with normal baseline and peak amplitude of Ca(2+) transients. Lmna(-/-) LV myocyte nuclei have marked alterations of shape and size with central displacement and fragmentation of heterochromatin; these changes are present but less severe in left atrial nuclei. Electron microscopy of Lmna(-/-) cardiomyocytes shows disorganization and detachment of desmin filaments from the nuclear surface with progressive disruption of the cytoskeletal desmin network. Alterations in nuclear architecture are associated with defective nuclear function evidenced by decreased SREBP1 import, reduced PPARgamma expression, and a lack of hypertrophic gene activation. These findings suggest a model in which the primary pathophysiological mechanism in Lmna(-/-) mice is defective force transmission resulting from disruption of lamin interactions with the muscle-specific desmin network and loss of cytoskeletal tension. Despite severe DCM, defects in nuclear function prevent Lmna(-/-) cardiomyocytes from developing compensatory hypertrophy and accelerate disease progression.  相似文献   
68.
BACKGROUND: Although more than 150,000 implantable cardioverter defibrillators (ICDs) are implanted yearly worldwide, only few studies systematically examined complications of ICD therapy in large patient cohorts. METHODS: We prospectively analyzed ICD-related complications in 440 consecutive patients who underwent first implantation of an ICD system for primary or secondary prevention of sudden cardiac death within the last 10 years at our institution. All study patients received pectoral nonthoracotomy ICD lead systems with the exception of one patient who had an artificial tricuspid valve. RESULTS: During 46 +/- 37 months follow-up, 136 of 440 patients (31%) experienced at least one complication including implant procedure-related complications in 43 patients (10%), ICD generator-related complications in 28 patients (6%), lead-related complications in 52 patients (12%), and inappropriate shocks in 54 patients (12%). The most serious complications included one perioperative death due to heart failure (0.2%), two ICD system infections necessitating device removal (0.5%) and two perioperative cerebrovascular strokes (0.5%). CONCLUSIONS: We conclude that more than one quarter of ICD patients experience complications during a mean follow-up of almost 4 years, although serious complications such as intraoperative death or ICD system infections are rare in patients with nonthoracotomy ICD systems. Recognition of these complications is the prerequisite for advances in ICD technology and management strategies to avoid their recurrence.  相似文献   
69.
Seven published, randomized, placebo‐controlled clinical trials with pregabalin have shown robust efficacy for relief of neuropathic pain from DPN and PHN. An investigation of the efficacy and safety of twice daily pregabalin enrolled 395 adults with painful DPN for ≥1 year in a 12‐week, double‐blind, placebo‐controlled trial. Patients were randomized to placebo, 150, 300, or 600mg/day pregabalin (n=96, 99, 99, and 101). Primary efficacy measure was change from baseline in endpoint mean pain score from patients’ daily pain diaries. Secondary efficacy measures included pain‐related sleep‐interference scores, Patient and Clinical Global Impressions of Change (PGIC, CGIC), and the EuroQOL Health Utilities Index (EQ‐5D). Statistically significant reduction in pain was observed in patients receiving pregabalin 600mg/day, and 46% of patients treated with 600mg/day pregabalin reported ≥50% improvement in mean pain scores from baseline (vs 30% of placebo patients, p=0.036). Number needed to treat to achieve such response was 6.3. Pregabalin 600mg/day was significantly superior to placebo in improving pain‐related sleep‐interference scores (p=0.003), PGIC (p=0.021), and CGIC (p=0.009). (Neither pregabalin 150 nor 300mg/day separated from placebo on these measures, largely because of an atypically large placebo response in one country representing 42% of patients.) All pregabalin dosages were superior to placebo in improving EQ‐5D utility scores (all p≥0.0263 vs placebo). Pregabalin was well tolerated at all dosages; adverse events were generally mild to moderate. Number needed to harm (discontinuation because of adverse events) was 10.3 for pregabalin 600mg/day.  相似文献   
70.
Purpose Improved segmentation of soft objects was sought using a new method that combines level set segmentation with statistical deformation models, using prior knowledge of the shape of an object as well as information derived from the input image. Methods Statistical deformation models were created using Euclidian distance functions of binary data and a multi-hierarchical registration approach based on mutual information metric and demons deformable registration. This approach is motivated by the fact that models based on signed distance maps, traditionally combined with level set segmentation can result in irregular shapes and do not establish explicit correspondences. By using statistical deformation models as representation of shape and a maximum a posteriori (MAP) estimation model to estimate the MAP shape of the object to be segmented, a robust segmentation algorithm using accurate shape models could be developed. Results The accuracy and correctness of the synthesized models was evaluated on different 3D objects (cardiac MRI and spinal CT vertebral segment) and the segmentation algorithm was validated by performing different segmentation tasks using various image modalities. The results of this evaluation are very promising and show the potential utility of the approach. Conclusion Initial results demonstrate the approach is feasible and may be advantageous over alternative segmentation methods. Extensions of the model, which also incorporate prior knowledge about the spatial distribution of grey values, are currently under development.  相似文献   
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