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991.
OBJECTIVE: Pathological aortic flow patterns differ significantly from haemodynamics within the healthy aorta. Development and impact of pathological flow is largely unknown and might affect pathogenesis and the progression of thoracic aortic diseases. This study presents pathological blood-flow patterns within a series of six patients suffering from ascending aortic aneurysms investigated with high-detail flow-sensitive, four-dimensional (4D)-MRI and three-dimensional (3D) computer-aided flow-visualisation strategies. METHODS: Data were acquired on a 3T magnetic resonance system (TRIO, Siemens, Erlangen, Germany) using a flow-sensitive 4D (time-resolved 3D) sequence protocol. Measurements were taken in synchrony with the cardiac cycle and under respiration control. After data pre-processing, blood-flow was visualised by means of systolic 3D streamlines and time-resolved 3D particle traces using the software EnSight (CEI, Apex, NC, USA) and homemade visualisation tools. We investigated six adult patients with ascending aortic aneurysms and one healthy individual and findings were compared to 3D-haemodynamics of the dilated ascending aorta described in current literature. RESULTS: Normal blood-flow in the healthy volunteer resulted in highest velocities of up to 1 ms in the ascending and descending aorta, a right-handed helical flow pattern featuring 0.5-1.5 revolutions within the ascending aorta was present. Two atherosclerotic aneurysms presented either increased right-handed helical flow with flow acceleration along the great curvature, or multiple vortical flows in the sinuses and middle of the ascending aorta. One Marfan-associated aneurysm exhibited increased vortical flow in the dilated sinuses. One pseudo-aneurysm at the proximal anastomosis of an earlier supracoronary aortic replacement showed extensive vortex formation inside the aneurysm's lumen. An aneurysm in a patient with a bicuspid aortic valve revealed one major vortex formation directly above the aortic valve. One aneurysm following congenital valvular stenosis and commissurotomy in childhood was characterised by helical diastolic backflow in the central ascending aorta and a vortex at the small curvature. CONCLUSION: Patients with ascending aortic aneurysms reveal considerable differences in local flow patterns among themselves and compared to healthy individuals. Further investigations are necessary to identify flow patterns predisposing to aortic aneurysm development or adverse events in the course of aortic disease.  相似文献   
992.
PURPOSE: To address the following questions: which parameters influenced the frequency of distant metastases in patients with locally advanced ear-nose-throat (ENT) tumors, which was the distribution pattern of metastases, and what were the diagnostic consequences for pretherapeutic staging? PATIENTS AND METHODS: 600 patients (526 men, 76 women, median age 56 years) with ENT tumors (squamous cell carcinoma histology) were studied retrospectively. The distribution of primary tumor site and stage (AJCC) was as follows: oropharynx: n = 161 (26.8%), hypopharynx: n = 187 (31.2%), oral cavity: n = 89 (14.8%), larynx: n = 118 (19.7%), cancer of unknown origin: n = 13 (2.2%), others: n = 32(5.3%), I: n = 24 (4%), II: n = 49 (8.2%), III: n = 89 (14.8%), IV: n = 438 (73%). 270 patients (45%) received radiochemotherapy, 330 (55%) postoperative radiotherapy. The following parameters were analyzed in association with distant metastases: tumor localization, T- and N-category, primary treatment, local tumor control, and second neoplasms. RESULTS: 114/600 patients (19%) developed distant metastases, 29/600 (4.9%) at presentation, 50% within 9.3 months after diagnosis of the primary tumor. Distant metastases were most frequent in stage IV (24.2%), carcinoma of the hypopharynx (25.7%), local recurrence (24.3%), and second neoplasm (31.7%) with the following distribution pattern: pulmonary 61/114 (53.5%), pleural 15/114 (13.1%), osseous 45/114 (39.5%), hepatic 14/114 (12.3%), cerebral 8/114 (7%), cutaneous 14/114 (12.3%). 34/114 patients (29.8%) presented monotopic, 80/114 (70.2%) polytopic metastases. 82/600 (13.6%) patients additionally had second neoplasms, 20 corresponding with synchronous or metachronous bronchial tumors. CONCLUSION: With locally advanced ENT tumor stage IVa/b, carcinoma of the hypopharynx, local recurrence or second neoplasms, at least a pretherapeutic CT of the thorax should be performed because every seventh patient (88/600) developed metastases or second primary tumors within the thoracic space during the course of disease. Regarding the side effects and costs of curative therapy, the definition of generally accepted guidelines for the systemic staging of locally advanced ENT tumors should be undertaken.  相似文献   
993.
The impact of vigilance states, such as sleep or arousal changes, on the high-frequency (600 Hz) components (HFOs) of somatosensory evoked potentials (SEPs) is known. The present study sought to characterize the effects of circadian fluctuations of tonic alertness on HFOs in awake humans. Median nerve SEPs were recorded at four times during a 24-hour waking period. In parallel to the SEP recordings, a reaction-time (RT) task was performed to assess tonic alertness. Additionally, the spontaneous EEG was monitored. The low-frequency SEP component N20 and the early and late HFO parts did not change across the measurement sessions. In contrast, RTs were clearly prolonged at night and on the second morning. EEG also showed increased delta power at night. HFOs are sensitive to pronounced vigilance changes, such as sleep, but are refractory to fluctuations of tonic alertness. Tonic alertness is regarded to be the top-down cognitive control mechanism of wakefulness, whereas sleep is mediated by overwhelming bottom-up regulation, which seems apparently more relevant for, at least in part, subcortically triggered high-frequency burst generation in the ascending somatosensory system.  相似文献   
994.
995.
Several models have previously been proposed to predict the probability of non-sentinel lymph node (NSLN) metastases after a positive sentinel lymph node (SLN) biopsy in breast cancer. The aim of this study was to assess the accuracy of two previously published nomograms (MSKCC, Stanford) and to develop an alternative model with the best predictive accuracy in a Czech population. In the basic population of 330 SLN-positive patients from the Czech Republic, the accuracy of the MSKCC and the Stanford nomograms was tested by the area under the receiver operating characteristics curve (AUC). A new model (MOU nomogram) was proposed according to the results of multivariate analysis of relevant clinicopathologic variables. The new model was validated in an independent test population from Hungary (383 patients). In the basic population, six of 27 patients with isolated tumor cells (ITC) in the SLN harbored additional NSLN metastases. The AUCs of the MSKCC and Stanford nomograms were 0.68 and 0.66, respectively; for the MOU nomogram it reached 0.76. In the test population, the AUC of the MOU nomogram was similar to that of the basic population (0.74). The presence of only ITC in SLN does not preclude further nodal involvement. Additional variables are beneficial when considering the probability of NSLN metastases. In the basic population, the previously published nomograms (MSKCC and Stanford) showed only limited accuracy. The developed MOU nomogram proved more suitable for the basic population, such as for another independent population from a mid-European country.  相似文献   
996.
Around 50 mycobacteria species cause human disease. Immunosuppressive states predispose to non-tuberculous mycobaterium infection, such as Mycobacterium chelonae: AFB, non-tuberculous, fast growth of low virulence and uncommon as a human pathogen. It may compromise the skin and soft tissues, lungs, lymph nodes and there is also a disseminated presentation. The diagnosis involves AFB identification and culture on Agar and Lowenstein-Jensen medium base. A 41-year-old female with MCTD (LES predominance) is reported, presenting painless nodules in the right forearm. She denied local trauma. Immunosuppressed with prednisone and cyclophosphamide for 24 months. Lesion biopsy has demonstrated positive bacilloscopy (Ziehl-Neelsen stain) and M.chelonae in culture (Lowenstein-Jensen medium base), therefore clarithromycin treatment has been started (best therapy choice in the literature).  相似文献   
997.
998.
Background

Obesity in the recipient is linked to inferior transplant outcome. Consequently, access to kidney transplantation (KT) is often restricted by body mass index (BMI) thresholds. Bariatric surgery (BS) has been established as a superior treatment for obesity compared to conservative measures, but it is unclear whether it is beneficial for patients on the waiting list.

Methods

A national survey consisting of 16 questions was sent to all heads of German KT centers. Current situation of KT candidates with obesity and the status of BS were queried.

Results

Center response rate was 100%. Obesity in KT candidates was considered an important issue (96.1%; n?=?49/51) and 68.6% (n?=?35/51) of departments responded to use absolute BMI thresholds for KT waiting list access with?≥?35 kg/m2 (45.1%; n?=?23/51) as the most common threshold. BS was considered an appropriate weight loss therapy (92.2%; n?=?47/51), in particular before KT (88.2%; n?=?45/51). Sleeve gastrectomy was the most favored procedure (77.1%; n?=?37/51). Twenty-one (41.2%) departments responded to evaluate KT candidates with obesity by default but only 11 (21.6%) had experience with?≥?n?=?5 transplants after BS. Concerns against BS were malabsorption of immunosuppressive therapy (39.2%; n?=?20/51), perioperative morbidity (17.6%; n?=?9/51), and malnutrition (13.7%; n?=?7/51).

Conclusions

Obesity is potentially limiting access for KT. Despite commonly used BMI limits, only few German centers consider BS for obesity treatment in KT candidates by default. A national multicenter study is desired by nearly all heads of German transplant centers to prospectively assess the potentials, risks, and safety of BS in KT waitlisted patients.

Graphical abstract
  相似文献   
999.

The present study aimed to investigate the long-term quality of life (QoL) in a large sample of pediatric obsessive–compulsive disorder (OCD) patients. The study included 220 pediatric OCD patients from the Nordic Long-term OCD Treatment Study (NordLOTS) who were evaluated at seven time points before, during, and after stepped-care treatment over a 3-year follow-up period. Data from three symptom severity trajectory classes formed the basis of the QoL evaluation: acute (n = 127, N = 147), slow (n = 46, N = 63), and limited responders (n = 47, N = 59). Patients’ QoL was assessed using parent and child ratings of the revised Questionnaire for Measuring Health-related Quality of Life in Children and Adolescents (KINDL-R). QoL was analyzed by trajectory class using a random mixed effects model. The association between pre-treatment factors and long-term QoL was investigated across classes in a multivariate model. Three years after treatment, the acute responder class had reached QoL levels from a general population, whereas the limited responder class had not. The slow responder class reached norm levels for the child-rated QoL only. Higher levels of co-occurring externalizing symptoms before treatment were associated with lower parent-rated QoL during follow-up, while adolescence and higher levels of co-occurring internalizing symptoms were associated with lower child-rated QoL during follow-up. For some patients, residual OCD symptoms in the years after treatment, even at levels below assumed clinical significance, are associated with compromised QoL. Co-occurring symptoms could be part of the explanation. Assessing QoL after OCD treatment, beyond the clinician-rated symptom severity, could detect patients in need of further treatment and/or assessment. Trial registry: Nordic Long-term Obsessive–Compulsive Disorder (OCD) Treatment Study; www.controlled-trials.com; ISRCTN66385119.

  相似文献   
1000.
In endodontic infections, inflammatory mediators such as cytokines are released, recruited and retained until the infection is eradicated. Root canal therapy is performed to prevent the spread of infection. The aim of this study was to investigate the effects of root canal debridement (cleaning and shaping) on periapical inflammation by measuring the levels of inflammatory cytokines, Interleukin‐8 (IL‐8) and Interleukin‐10 (IL‐10). The study includes twenty patients with pulp necrosis and asymptomatic apical periodontitis. Periradicular sample was collected using paper points before and after root canal debridement. Cytokine levels were determined by Sandwich Enzyme‐Linked Immunosorbent Assay (ELISA). Data were analysed using paired t‐test (PASW Statistics 18) (P = 0.05). All samples showed the presence of IL‐8 and IL‐10 prior to root canal debridement. Significantly reduced levels (P < 0.05) of IL‐8 and IL‐10 were detected after root canal debridement. In conclusion, root canal debridement significantly decreased the levels of the tested pro‐ and anti‐inflammatory cytokine in the periradicular interstitial fluid.  相似文献   
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