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121.
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Background

Gastric cancer is fourth on the incidence list of cancers worldwide with a high disease-related mortality rate. Curation can only be achieved by a radical resection including an adequate lymphadenectomy. However, prognosis remains poor and cancer recurrence rates are high, also due to lymph node metastases. To improve outcome, (neo)adjuvant treatment strategies with chemo- and/or radiotherapy regimes are employed.

Aims

Accurate staging of gastric cancer at primary diagnosis is essential for adequate treatment. In this non-systematic review the role 18-F-Fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) in preoperative staging is investigated. Furthermore, the results of neoadjuvant chemotherapy-induced tumour response monitoring by FDG-PET are discussed.

Results and conclusion

It is concluded that currently FDG-PET has no role in the primary detection of gastric cancer due to its low sensitivity. FDG-PET shows, however, slightly better results in the evaluation of lymph node metastases in gastric cancer compared to CT and could have therefore a role in the preoperative staging. Improvement in accuracy could be achieved by using PET/CT or other PET tracers than FDG, but these modalities need further investigation. FDG-PET, however, adequately detects therapy responders at an early stage following neoadjuvant chemotherapy.  相似文献   
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Background Pressure ulcers have a known impact on quality of life as well as on morbidity and mortality of the persons affected. Remarkable differences in pressure ulcer prevalence between the Netherlands and Germany have been found during the last 6 years. This study explores to what extent the individual risk of the population and quality indicators of the institutions can explain the variation in national prevalence. Methods Data of a binational multi‐centred cross‐sectional study in 103 hospitals (n = 21 378 patients) and 129 nursing homes (n = 15 579 residents) were analysed using random effects regression models to calculate the differences in national prevalences within the nursing homes and hospitals, adjusted for personal risk for pressure ulcer and quality indicators. Results The prevalence of pressure ulcers among the at‐risk group (Bradenscore ≤20) in nursing homes was 30.8% in the Netherlands and 8.3% in Germany [OR: 4.9 (CI 95%: 4.2–5.7)]. In hospitals, the prevalence among the at‐risk group was 26.1% in the Netherlands and 21.2% in Germany [OR: 1.3 (CI 95%: 1.2–1.5)]. After adjusting for individual risk factors (age, gender, Bradenscore) as well as for quality structures (use of prevention and treatment protocols, experts groups, information leaflets, nurses training, central pressure ulcer statistics and regular updating of protocols), the chance of developing a pressure ulcer was 6.05 times higher (CI 95%: 4.0–9.2) in a Dutch nursing home than in a German nursing home. Within the hospitals, the OR for Dutch patients was 2.03 (CI 95%: 1.4–3.0). Conclusion A remarkable national variation exists in pressure ulcer prevalence and nursing practice. Neither the populations vulnerability for pressure ulcers nor pressure ulcer management as measured in this study could explain this national variation. Therefore, other risk factors should be taken into consideration. Additionally, it is possible that quality indicators are implemented in differing ways with varying levels of effectiveness. Therefore, further research is needed to examine prospectively and in more detail the reality of care within facilities in both countries.  相似文献   
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Aims and objectives. The aim of this study is to investigate if a general instrument (Care Dependency Scale; CDS) has the same sensitivity and specificity as a specific instrument (Hendrich Fall Risk Model; HFRM) in a screening for fall risks. Background. Falls of older patients are a common problem in hospitals. Apart from falls risk, nurses have to use many assessment tools to detect the patients’ different care problems. To decrease the workload it would be helpful to have a general instrument used as a first screening for possible risks for different healthcare problems, such as falls, instead of specific risk instruments for each individual healthcare problem. Design. A prospective design was used by measuring each patient upon admission and by registering all falls during their hospital stay. Methods. The sample consisted of 560 patients of a geriatric hospital in Germany. All of whom gave their informed consent to participate in the study. Nurses filled in the CDS and the HFRM at the time of hospital admission. Results. The CDS (cut off point ≤54) had a sensitivity of 75% (47/63 fallers) and a specificity of 46% (227/497 non‐fallers). The HFRM (cut off point ≥11) had a sensitivity of 75% (47/63 fallers) and a specificity of 47% (237/497 non‐fallers). Conclusion. The results of the CDS are similar to those of the HFRM in predicting falls. Relevance to clinical practice. The use of the CDS is preferred as it is more general and more reliable than the HFRM. The workload for nursing staff can be decreased when only one instrument is used.  相似文献   
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Retrograde transurethral balloon dilation of the prostatic urethra was performed in five human volunteers with benign prostatic hypertrophy. Each patient underwent cystoscopy, uroflow studies, voiding cystourethrography, retrograde urethrography, and magnetic resonance imaging before dilation and at defined intervals afterward. The longest follow-up to date is 8 months. Patients were given topical anesthetics and mild sedatives, and dilation was performed with a 25-mm urethroplasty balloon catheter inflated at 3-6 atm for 10 minutes. All catheter manipulations were done with a guide wire and under fluoroscopic control. Significant resolution of symptoms of prostatism was seen in four patients. The unsatisfactory results in the last patient were believed to be caused by ineffectual dilation of predominantly middle lobe hypertrophy--a condition that is now regarded as a contraindication to dilation. This technique has promise to replace transurethral resection of the prostate as the treatment of choice for this common male ailment.  相似文献   
129.
A new guide wire that provides markedly improved torque control is described. It was compared with a conventional guide wire in two models, one simulating a drainage tube with numerous side holes and one, the biliary tree. The new wire was much more easily controlled than the conventional guide wire and passed through both models significantly faster (P less than .01 and P less than .005). Although some deterioration in control was noted when it was inserted through a catheter in vivo, the new torque-control wire still exhibited a definite improvement over conventional wires in directional control.  相似文献   
130.
Mechanical clot dissolution: new concept   总被引:3,自引:0,他引:3  
The authors present preliminary data on in vitro mechanical clot dissolution by means of a catheter with a tiny high-speed propeller enclosed in a special housing. Preweighed human blood clots were subjected to the catheter in a test tube with saline at various propeller speeds and durations of application. After filtration of the resultant slurry, the clot residue was weighed and examined histologically. Clot dissolution was found to be related to both the duration and speed of propeller rotation. No fibrin residue was seen after dissolution, although potential embolic material, composed of clumps of cellular debris as large as 208 microns in longest dimension, was found. Mechanical clot dissolution could possibly be used in any natural or synthetic blood vessel in which there is acute or subacute thrombosis, with fewer complications and lower cost than obtained with traditional methods.  相似文献   
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