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排序方式: 共有764条查询结果,搜索用时 15 毫秒
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Primary primitive neuroectodermal tumor of the cauda equina 总被引:5,自引:0,他引:5
Primitive neuroectodermal tumors (PNETs) are aggressive neoplasms composed predominantly of undifferentiated cells that show evidence of neural differentiation. Although their classification has been controversial, PNETs are well recognized primary tumors of both central and peripheral nervous systems. PNETs must be distinguished from other round-cell tumors, including Ewing's sarcoma, lymphoma, rhabdomyosarcoma, and small cell carcinoma. Intraspinal PNETs are rare neoplasms that are usually metastatic in origin. We describe the eighth reported primary PNET of the cauda equina that developed in a 52-year-old man with no significant medical history. The tumor was characterized by Homer-Wright rosettes and immunoreactivity for CD99, glial fibrillary acidic protein, neuron-specific enolase S100, and synaptophysin. The anatomic location of primary intrathecal PNETs is important as those arising in the spinal cord develop in the central nervous system, whereas those arising in the cauda equina develop in the peripheral nervous system. The histogenesis of intrathecal PNETs may be multifactorial. 相似文献
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Pétas A Isotalo T Talja M Tammela TL Välimaa T Törmälä P 《Scandinavian journal of urology and nephrology》2000,34(4):262-266
OBJECTIVE: Interstitial laser coagulation (ILC) of the prostate induces necrosis, oedema and increased risk for postoperative urinary retention. The present randomized study was carried out to investigate the feasibility and efficacy of a biodegradable self-reinforced polyglycolic acid (SR-PGA) stent in preventing postoperative urinary retention and the need for prolonged catheterization after ILC treatment. MATERIAL AND METHODS: 35 males with benign prostatic enlargement (BPE) entered the study: 21 in the ILC + stent group and 14 in the ILC group without a stent. A suprapubic catheter was inserted for all patients and ILC was performed. The SR-PGA stent was inserted immediately after laser therapy in the stent group and kept open until the next morning when it was closed and the patient started trying to void. The suprapubic catheter was removed after voiding had started and the urinary bladder emptied adequately. RESULTS: In the ILC + stent group voiding started on the first postoperative day in 17 patients and on the second day in 2 patients. Voiding was delayed in 2 cases: in 1 case due to inadequate length of the stent and in the other as a result of the stent placement being too proximal. There was 1 case of urinary retention due to early degradation of the stent. In the ILC-only group voiding started on average 6.1 days postoperatively. At 1 month follow-up, the mean peak urinary flow rate had increased significantly in the ILC + stent group (p < 0.05) but not in the ILC-only group (p = 0.26). Improvements in symptom scores were significant in both groups (p < 0.005) but in terms of the mean peak urinary flow rates at 6 months follow-up the improvement was significant only in the stent group (p < 0.05). CONCLUSIONS: The use of a SR-PGA stent enabled early voiding and is safe and effective in the treatment of postoperative urinary retention after ILC. The 3-4 week degradation time of the SR-PGA stent was too short for some patients. There is still a need for further development work to improve the stents and larger controlled studies to show the true value of biodegradable stents in the treatment of BPE. 相似文献
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Shigematsu R Okura T Nakagaichi M Tanaka K Sakai T Kitazumi S Rantanen T 《The journals of gerontology. Series A, Biological sciences and medical sciences》2008,63(1):76-82
BACKGROUND: Decreased fitness of the lower extremities is a potentially modifiable fall risk factor. This study aimed to compare two exercise programs--square-stepping exercise (SSE), which is a low-cost indoor program, and walking--for improving the fitness of the lower extremities. METHODS: We randomly allocated 68 community-dwelling older adults (age 65-74 years) to either the SSE or walking group (W group). During the 12-week regimen, the SSE group participated in 70-minute exercise sessions conducted twice a week at a local health center, and the W group participated in outdoor supervised walking sessions conducted weekly. The W group was instructed to increase the number of daily steps. Prior to and after the program, we obtained information on 11 physical performance tests for known fall risk factors and 3 self-reported scales. The fall incidence was followed-up for 8 months. RESULTS: At 12 weeks postregimen, significant differences were observed between the two exercise groups with respect to leg power (1 item), balance (2 items), agility (2 items), reaction time (2 items), and a self-reported scale (1 item); the SSE group demonstrated a marked improvement in the above-mentioned items with Group x Time interactions. Significant time effects were observed in the tests involving chair stands, functional reach, and standing up from a lying-down position without Group x Time interactions. During the follow-up period, the fall rates per person-year in the SSE and W groups were 23.4% and 33.3%, respectively (p =.31). CONCLUSION: Although further studies are required, SSE is apparently more effective than walking in reducing fall risk factors, and it appears that it may be recommended as a health promotion exercise in older adults. 相似文献
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Anu Muraja‐Murro Antti Kulkas Mikko Hiltunen Salla Kupari Taina Hukkanen Pekka Tiihonen Esa Mervaala Juha Töyräs 《Journal of sleep research》2013,22(6):663-669
Obstructive sleep apnea (OSA) is linked to an increased mortality rate. However, the severity of individual obstruction events is rarely considered quantitatively in clinical practice. We hypothesized that OSA with especially severe obstruction events would predispose a patient to greater health risks than OSA with a similar apnea–hypopnea index (AHI), but lower severity of individual events. This hypothesis was tested in a follow‐up (198.2 ± 24.7 months) of a population of 1068 men referred for ambulatory polygraphic recording due to suspected OSA. The recordings were analysed according to the guidelines of the American Academy of Sleep Medicine. Furthermore, a novel obstruction severity parameter was determined; this was defined as the product of duration of the individual obstruction event and area of the related desaturation event. Patients treated with continuous positive airway pressure (CPAP) were omitted. We identified 125 deceased patients from our original population and for 113 of these a matching alive patient with similar AHI, age, body mass index (BMI), smoking habits and follow‐up time could be found. The deceased patients with severe OSA (based on conventional AHI) showed higher obstruction severity values than their AHI‐matched alive controls. Based on the multivariate logistic regression analysis, obstruction severity was the only parameter which was related statistically significantly to mortality in the severe OSA category. Furthermore, 59% of all deceased patients and 83% of those who had severe OSA displayed higher obstruction severity than the AHI‐matched alive counterparts. To conclude, the obstruction severity parameter provided valuable prognostic information supplementing AHI. The obstruction severity parameter might improve recognition of the patients with the highest risk. 相似文献
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Stenholm S Rantanen T Heliövaara M Koskinen S 《Journal of the American Geriatrics Society》2008,56(3):462-469
OBJECTIVES: To study the association between different obesity indicators and walking limitation and to examine the role of C‐reactive protein (CRP) and handgrip strength in that association. DESIGN: A cross‐sectional, population‐based study. SETTING: The Health 2000 Survey with a representative sample of the Finnish population. PARTICIPANTS: Subjects aged 55 and older with complete data on body composition, CRP, handgrip strength, and walking limitation (N=2,208). MEASUREMENTS: Body composition, anthropometrics, CRP, medical conditions, handgrip strength, and maximal walking speed were measured in the health examination. Walking limitation was defined as maximal walking speed less than 1.2 m/s or difficulty walking half a kilometer. RESULTS: The two highest quartiles of body fat percentage and CRP and the two lowest quartiles of handgrip strength were all significantly associated with greater risk of walking limitation when chronic diseases and other covariates were taken into account. In addition, high CRP and low handgrip strength partially explained the association between high body fat percentage and walking limitation, but the risk of walking limitation remained significantly greater in persons in the two highest quartiles than in those in the lowest quartile of body fat percentage (odds ratio (OR)=1.75, 95% confidence interval (CI)=1.19–2.57 and OR=2.80, 95% CI 1.89–4.16). The prevalence of walking limitation was much higher in persons who simultaneously had high body fat percentage and low handgrip strength (61%) than in those with a combination of low body fat percentage and high handgrip strength (7%). Using body mass index and waist circumference as indicators of obesity yielded similar results as body fat percentage. CONCLUSION: Low‐grade inflammation and muscle strength may partially mediate the association between obesity and walking limitation. Longitudinal studies and intervention trials are needed to verify this pathway. 相似文献