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101.
Omokawa S Ryu J Tang JB Han J Kish VL 《Clinical orthopaedics and related research》2000,(372):262-271
This study measured the changes in moment arm length of thumb motor tendons after simulated ligamentous instability and subsequent reconstruction of the trapeziometacarpal joint. Excursions of thumb motor tendons were measured simultaneously with the trapeziometacarpal joint angulation during flexion to extension and abduction to adduction motion. Tendon moment arms were calculated based on joint and tendon displacement techniques in the intact joint, after sequential sectionings of the capsuloligamentous restraints, and after the reconstruction procedure of Eaton and Littler. The results showed that moment arms of the abductor pollicis longus and extensor pollicis brevis tendons increased significantly as compared with those for normal joints during flexion to extension motion after sectioning the palmar capsuloligamentous components. After the ulnopalmar structures were cut, the moment arm of the extensor pollicis longus tendon had a statistically significant increase during abduction to adduction motion, and those of the extensor and flexor pollicis longus tendons decreased significantly during flexion to extension motion. Changed moment arms were restored to a normal level after the ligamentous reconstruction. These results indicate that ligamentous disruptions alter the mechanical balance of thumb motor tendons, which may contribute to joint deformities observed in trapeziometacarpal joint arthritis. Restoring joint stability is important to correct mechanical imbalance of the tendons. 相似文献
102.
Oh BR Sasaki M Perinchery G Ryu SB Park YI Carroll P Dahiya R 《The Journal of urology》2000,163(5):1584-1587
PURPOSE: Tumor necrosis factor-alpha (TNF-alpha) is involved in oncogenesis of several cancers. The purpose of this study was to investigate whether genotype changes of TNF-alpha promoter regions (-238, -308) and at the 488 region are associated with human prostate cancer. MATERIALS AND METHODS: The DNA from 73 cases of human prostate cancer was analyzed by allele-specific polymerase chain reaction to characterize the genotype changes of three regions of the TNF-alpha gene in prostate cancer patients. We also determined the genotype frequency in these patients. The relative risk of variant genotype was calculated by comparing with our previous data from healthy controls. RESULTS: Genetic changes were detected in 15.1% (11/73) of prostate cancer samples at 488 region of TNF-alpha. Seventy-three percent (53/73) of the patients showed genotype GA at -308 region of TNF-alpha. Genotype GA at 488 region in TNF-alpha was observed in 73% (53/73) of the cancer and 71% (52/73) of the normal tissue. The relative risks of incidence for prostate cancer was 14-fold higher in people with genotype GA at -308 region of TNF-alpha. The relative incidence for prostate cancer was a 17-fold higher in-patient with genotype GA at 488 region of TNF-alpha. Genotype GA at -308 of TNF-alpha was related to higher clinical tumor stage of prostate cancer than genotype G (p <0.05). CONCLUSIONS: The present study demonstrates, for the first time, that the genotype changes in -308 and 488 regions of TNF-alpha are associated with prostate cancer. 相似文献
103.
Epilepsy surgery has emerged as an important option in the treatment of children with epilepsy that is refractory to antiepileptic drug management. The cornerstone of successful surgery is accurate localization of the brain region of seizure onset. Traditional techniques of seizure onset localization, e.g. surface electroencephalography (EEG) recording and magnetic resonance imaging (MRI), allow accurate localization in a significant number of patients. When the focus of seizure onset is not apparent from these non-invasive techniques, other methods of localization, e.g. intracranial EEG recording, may be needed before resection of the focus. Single-photon emission computed tomography (SPECT) is a nuclear medicine blood-flow technique that has been used to identify a region of epileptogenic brain associated with low blood flow in the resting state (interictal SPECT) or increased blood flow at the time of seizure activity (ictal SPECT). This report describes the validation and utility of a computer-assisted method of subtracting the interictal from the ictal SPECT scans and co-registering the difference image on the MRI. This method, called subtraction ictal SPECT co-registered on MRI (SISCOM), is used in guiding the location and the extent of intracranial electrode implantation, or in obviating the need for the implantation in some cases. 相似文献
104.
105.
Fibrous dysplasia, in general, appears as an area of markedly increased uptake on bone scintigraphy. Therefore, the possibility of fibrous dysplasia is likely to be excluded when the lesion shows no or slightly increased uptake. The authors report a case of incidentally detected fibrous dysplasia that appeared as slightly increased uptake on bone scintigraphy and was found to harbor a bone infarction along with typical fibrous dysplasia by pathologic examination of a specimen sampled by curettage. Barely increased bone uptake in fibrous dysplasia may be associated with decreased vascularity and osteoblast activity of the lesion as a result of concurrent bone infarction. The authors suggest that not every case of fibrous dysplasia appears as an area of intensely increased uptake on a bone scan. Clinicians should be cautious in interpreting bone scans of radiographically indicated fibrous dysplasia. 相似文献
106.
Alveolar soft part sarcoma: MR and angiographic findings 总被引:5,自引:5,他引:0
Suh JS Cho J Lee SH Shin KH Yang WI Lee JH Cho JH Suh KJ Lee YJ Ryu KN 《Skeletal radiology》2000,29(12):680-689
Objective. To present the MR and angiographic findings of alveolar soft part sarcoma (ASPS).
Design and patients. MR examinations (12 tumors of 10 patients) of ASPS performed at multiple hospitals were retrospectively reviewed. The tumors
were found in the thigh (n=4), lower leg (n=4), femur (n=2, local metastasis), scalp (n=1) and arm (n=1). The MR signal characteristics including signal intensity, homogeneity and signal void of lesions and bony invasion including
direct invasion or local metastasis were evaluated. Angiographic findings (n=4) and post-embolotherapy follow-up MR imaging (n=2) findings were also assessed.
Results. Local bony metastasis was found in two cases. Seven tumors showed heterogeneous high signal intensity on T1- and T2-weighted
images with good enhancement. One tumor had a very high signal on T1-weighted images. Eight tumors (67%) showed numerous signal
voids in or near the tumors. All four angiographic studies showed numerous enlarged vessels, arteriovenous shunts and delayed
washout. Two cases mimicked arteriovenous malformations on angiographic studies but MR images demonstrated solid soft tissue
components as well as tortuous vessels.
Conclusions. High signal on T1-weighted image and numerous signal voids are highly suggestive of ASPS, although they are not universal
as has been suggested and arteriovenous malformation should be included in the differential diagnosis. Local bony metastases
in ASPS were seen in two cases and should be carefully investigated.
Received: 12 April 2000 Revision requested: 27 June 2000, 8 August 2000 Revision received: 2 August 2000, 21 August 2000 Accepted:
22 August 2000 相似文献
107.
新近的临床试验资料,包括2009年美国临床肿瘤协会(ASCO)年会上报道的资料,有力地推动了对晚期非小细胞肺癌(NSCLC)患者的现代治疗策略的改革。此改革蕴含的主题包括:(1)基于组织学类型的治疗,(2)预 相似文献
108.
Despite marked development in cancer therapies during recent decades, the prognosis for advanced cancer remains poor. The conventional tumor–cell‐centric view of cancer can only explain part of cancer progression, and thus a thorough understanding of the tumor microenvironment (TME) is crucial. Among cells within the TME, cancer‐associated fibroblasts (CAFs) are attracting attention as a target for cancer therapy. However, CAFs present a heterogeneous population of cells and more detailed classification of CAFs and investigation of functions of each subset is needed to develop novel CAF‐targeted therapies. In this context, application of newly developed approaches to single‐cell analysis has already made an impact on our understanding of the heterogeneity of CAFs. Here, we review the recent literature on CAF heterogeneity and function, and discuss the possibility of novel therapies targeting CAF subsets. 相似文献
109.
Changjoo Ahn Changshin Kang Hong Joon Ahn Yeonho You Jung Soo Park Jin Hong Min Wonjoon Jeong Yongchul Cho Seung Ryu Yong Nam In 《Medicine》2022,101(46)
Cholesterol is an essential substance to maintain cell membranes. Low levels of total cholesterol (TC) are associated with poor prognosis in critically ill patients. Cardiac arrest-induced whole-body ischemia and reperfusion injury cause a sepsis-like syndrome. The Cholesterol level in post-cardiac arrest patients may indicate the degree of endotoxemia or inflammation caused by ischemic and reperfusion injury. We aimed to investigate the association of TC levels with neurologic outcome of out-of-hospital cardiac arrest (OHCA) survivors who underwent target temperature management (TTM). This was a retrospective single-center observational study from May 2018 to April 2021 on a cohort of 106 patients. TC levels were determined in samples obtained immediately and at 24, 48, and 72 hours after the return of spontaneous circulation (ROSC). The primary outcome was poor neurologic outcome at 3 months after ROSC. Poor neurologic outcome was defined by cerebral performance categories 3 to 5. Sixty patients had a poor neurologic outcome. TC levels were significantly lower in the poor neurologic outcome group at each time point. The TC levels for predicting poor neurologic outcome had a sensitivity of 80.8%, with 67.6% specificity at 48 hours (TC48) after ROSC. The areas under the curve value of TC48 was 0.771 (0.670–0.853), with a cutoff value of 114 mg/dL. TC level at 48 hours after ROSC was a helpful marker for the 3-month poor neurologic outcome. This might be an easily accessible predictive marker of neurologic outcome in OHCA survivors treated with TTM. 相似文献
110.
Sukhyun Ryu June Young Chun Sunmi Lee Daesung Yoo Yongdai Kim Sheikh Taslim Ali Byung Chul Chun 《Viruses》2022,14(11)
The epidemiology and transmission dynamics of infectious diseases must be understood at the individual and community levels to improve public health decision-making for real-time and integrated community-based control strategies. Herein, we explore the epidemiological characteristics for assessing the impact of public health interventions in the community setting and their applications. Computational statistical methods could advance research on infectious disease epidemiology and accumulate scientific evidence of the potential impacts of pharmaceutical/nonpharmaceutical measures to mitigate or control infectious diseases in the community. Novel public health threats from emerging zoonotic infectious diseases are urgent issues. Given these direct and indirect mitigating impacts at various levels to different infectious diseases and their burdens, we must consider an integrated assessment approach, ‘One Health’, to understand the dynamics and control of infectious diseases. 相似文献