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1.
Experimental studies revealed that the contractile response of the urinary bladder to sacral anterior root stimulation depends on the actual bladder volume. Furthermore, no clinical relevant technique is available for continuous monitoring of the bladder wall distension respectively bladder volume in paraplegic patients. The presented study investigates the reliability of especially developed implantable ultrasound sensors as a sensoric system for continuous monitoring of the bladder volume. In six anaesthesized pigs two ultrasound sensors, one transmitter and one receiver, were implanted on the bladder wall at different locations (latero-lateral, dorsal-ventral, rostral-caudal). After closing the abdominal wall, the bladder was filled in 50 ml steps up to 250 ml. After each filling step the running time of the ultrasound signal was measured. In all experiments reproducible results and a high correlation of the measured running times with bladder volume were observed. The latero-lateral configuration of the sensors seemed to be most confidential. The presented study indicates that bladder volumetry with implantable ultrasound sensors is possible with minimal technical prerequisites. This promising technique for continuous bladder volumetry could play an important role in the development of an intelligent and autoadaptive neurostimulator of the urinary bladder in paraplegic patients.  相似文献   
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Purpose

The aim of this prospective study was to assess lung ultrasonography as an alternative to bedside radiography for the diagnosis of neonatal pneumonia.

Patients & methods

The study was performed on 75 neonates admitted during the period from October 2011 to October 2012 in the NICU of Cairo University Pediatric Hospital presenting with clinical picture of pneumonia. Chest X-rays and lung US were done.

Results

Chest X-ray findings denoting lung infections were present in 64 cases (85.3%), and the remaining 11 cases (14.6%) had a free chest X-ray. Ultrasonography revealed pneumonic patches in 68 patients (90.6%), 7 (9.3%) had free US scans. US and chest X-rays detected pneumonic patches in 64 cases (85.3%), US detected pneumonic patches in 18 cases (24%) with chest X-rays having signs of chest infections other than pneumonic patches and in 4 cases (5.3%) with clear chest X-rays.

Conclusion

Bedside lung ultrasonography is highly sensitive, specific, and reproducible for ruling out underlying pneumonic process as well as in early detection and follow up of possible complications and can be considered an attractive alternative to bedside chest radiography and thoracic computed tomography with minimal radiation exposure.  相似文献   
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AIMS: Patients with spinal cord injury often present with dysfunction of urinary bladder and urethral sphincter. One treatment option is sacral rhizotomy and sacral anterior root stimulation with the Finetech Brindley stimulator. However, a major disadvantage is the lack of selective stimulation, resulting in simultaneous contraction of sphincter and bladder followed by unphysiological micturition. This study investigated the possibility of selective bladder stimulation by using a Brindley electrode. METHODS: In 11 male anaesthetized foxhounds, a complete posterior rhizotomy was perormed. The anterior S2 roots were stimulated with different quasi-trapezoidal (QT) pulses (pulse length range, 600-1,400 microsec; stimulation current, 0.1-2.0 mA; frequency, 20 Hz) by using a tripolar Brindley electrode. Sphincter and bladder pressures were measured urodynamically. RESULTS: All 11 animals showed a maximal reduction of the highest sphincter pressure over 80%, and in 6 of 11 trials, the sphincter pressure was inhibited completely (100%). With stimulations at maximal sphincter blockade, the average achievable bladder pressure was 33.48 cm H(2)O higher than the average sphincter pressure, and in three cases, a strong micturition was observed. Selective blockade of the sphincter was possible by applying QT pulses. The bladders remained uninfluenced by this blockade and kept their excitability at any time. CONCLUSIONS: This study shows that selective bladder stimulation with little or no coactivation of the sphincter is possible. A physiological micturition can be achieved by using a tripolar Brindley electrode. Introduction of this stimulation technique into clinical practice should not face major difficulties, considering that the device is an established electrode.  相似文献   
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Spatio-temporal processing of whisker information was analysed in vivo for single neurons in D2 barrel columns of S1 cortex in Tg8 mutant mice, which lack barrels. Findings were compared with normal C3H mice of the same genetic background. The topographical organization of functional columns was similar in Tg8 and normal mice. Response magnitudes (RMs) to D2 principal whisker deflections in D2 columns for Tg8 were similar to normals for layers I-III and layer IV cells but short latency responses (>10 ms post-stimulus) were twice the magnitude of normal mice. The surrounding whiskers D1 and D3 yielded smaller RMs in layer IV of mutants than normal mice whereas RMs in layers I-III were equipotent (P>0.5). Modal latencies were shorter in Tg8 mice in all layers. Latency distributions for whisker D2 responses in both laminae were bimodal in normal mice, peaking at 6-8 and 12 ms post-stimulus, but unimodal in Tg8 mice in both laminae, peaking at 6-8 ms. Hence, despite an absence of barrels, segregation of columns is enhanced in layer IV and sensory processing is faster in layers I-IV compared with normal mice. This contrasts with adenylyl cyclase knockout mice where both an absence of barrels and enhanced surrounding whisker responses have been observed. These findings suggest that factors other than barrels and clustering of thalamo-cortical terminals define receptive field geometry.  相似文献   
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Introduction The aim of this study was to analyze the features of patients with goiter who underwent thyroidectomy via a cervical incision and a median sternotomy in Khartoum. Methods A total of 267 thyroidectomies were performed in Khartoum Teaching Hospital during the period from January 2002 to December 2003. There were 40 patients with evidence of retrosternal goiter (15%). Of those 40 patients, 13 had clinical and radiologic evidence of deep retrosternal extension of the goiter possibly necessitating sternotomy. Only 9 of the 13 patients actually required sternotomy, which accounted for 3.4% of all thyroidectomies performed (n = 267). The clinical, radiologic, and pathologic findings of those 9 sternotomy patients were analyzed and compared to those of the 258 patients who underwent cervical thyroidecomy. Results Total thyroidectomy was undertaken in all nine patients. Six of them had retrosternal extension on the right side of the mediastinum, and three had bilateral extension. Seven patients had symptoms of respiratory distress, and two were asymptomatic. The duration of the goiter ranged between 7 and 30 years. The chest radiograph and computed tomography scan revealed that the retrosternal part was below the level of the aortic knuckle at the tracheal bifurcation in all cases. The histopathology revealed a simple multinodular goiter in eight of the nine patients (89%) and in one patient with papillary carcinoma. Five of the nine patients underwent intraoperative prophylactic tracheostomy due to tracheomalacia. Conclusions A long-standing goiter with deep (below the aortic knuckle) mediastinal extension and tracheal space compromise can be postulated to increase the likelihood of sternotomy.  相似文献   
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Targeting Notch signaling in autoimmune and lymphoproliferative disease   总被引:1,自引:0,他引:1  
Patients with autoimmune lymphoproliferative syndrome (ALPS) and systemic lupus erythematosis (SLE) have T-cell dysregulation and produce abnormal, activated T lymphocytes and an atypical peripheral T-cell population, termed double negative T cells (DNTs). T-cell functions, including DNT transition in T-cell development and T-cell activation, are critically dependent on Notch signaling. We hypothesized that inhibiting Notch signaling would be effective in ALPS and SLE by reducing the production of abnormal DNTs and by blocking aberrant T-cell activation. We tested this hypothesis using murine models of ALPS and SLE. Mice were randomized to treatment with the notch pathway inhibitor (gamma-secretase inhibitor), N-S-phenyl-glycine-t-butyl ester (DAPT), or vehicle control. Response to treatment was assessed by measurement of DNTs in blood and lymphoid tissue, by monitoring lymph node and spleen size with ultrasound, by quantifying cytokines by bead-array, by ELISA for total IgG and anti-double-stranded DNA (dsDNA) specific antibodies, and by histopathologic assessment for nephritis. We found a profound and statistically significant decrease in all disease parameters, comparing DAPT-treated mice to controls. Using a novel dosing schema, we avoided the reported toxicities of gamma-secretase inhibitors. Inhibiting the Notch signaling pathway may thus present an effective, novel, and well-tolerated treatment for autoimmune and lymphoproliferative diseases.  相似文献   
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neurogenetics - Evidence about the link between glucocerebrosidase (GCase) and parkinsonism is growing. Parkinsonism was described in adult type 1 Gaucher disease (GD); few case reports described...  相似文献   
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