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41.
尿微卫星不稳定性研究对膀胱肿瘤诊断的探讨 总被引:1,自引:0,他引:1
目的:探讨尿微卫星不稳定性改变(MSI)与膀胱移行细胞癌(TCC)临床病理特征的关系及其在早期诊断中的价值。方法:选择36例TCC患者5个微卫星位点,应用聚合酶链反应-变性聚丙烯酰胺凝胶银染法分析尿微卫星的改变。结果:36例中有22例(61.11%)出现微卫星不稳定性改变(LOH/MSI),并与肿瘤的分期、分级无关(P>0.05);尿脱落细胞学检查的阳性率为22.22%(8/36),两者相比差异有统计学意义(P<0.05)。结论:尿沉渣微卫星不稳定性分析对膀胱癌的早期诊断有一定的意义,是尿脱落细胞学检查的重要补充。所选微卫星位点为本地区膀胱癌的进一步研究奠定了基础。 相似文献
42.
大肠重复癌MMR、p53、Bax、PCNA表达及微卫星不稳定性研究 总被引:3,自引:0,他引:3
目的探讨微卫星不稳定性 (MSI)在大肠重复癌与单发癌中的变化规律 ,及MMR、p5 3、Bax、PCNA表达与MSI的关系。 方法采用免疫组化、PCR SSLP法对 38例大肠重复癌患者的 5 1处癌灶及 35例单发大肠癌分别进行MMR、p5 3、Bax、PCNA表达的检测和 5个微卫星位点MSI检测。结果重复癌组复制错误阳性率为 5 3% (2 7/ 5 1) ,单发癌组为 17% (6 / 35 ) ,差异有显著性意义 (χ2 =11 2 5 ,P <0 0 1)。重复癌组中 ,RER 与MMR表达缺失有密切的相关性 ;RER 与 p5 3表达呈负相关 ;RER 组PCNA标记指数显著低于RER-组 ;RER 与低分化、近端大肠癌密切相关。结论MSI在大肠重复癌的发生上起着重要作用 ,MSI可作为预测大肠重复癌发生的重要标志。 相似文献
43.
Genetic contributions to Parkinson's disease 总被引:8,自引:0,他引:8
Sporadic Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by the loss of midbrain dopamine neurons and Lewy body inclusions. It is thought to result from a complex interaction between multiple predisposing genes and environmental influences, although these interactions are still poorly understood. Several causative genes have been identified in different families. Mutations in two genes [α-synuclein and nuclear receptor-related 1 (Nurr1)] cause the same pathology, and a third locus on chromosome 2 also causes this pathology. Other familial PD mutations have identified genes involved in the ubiquitin–proteasome system [parkin and ubiquitin C-terminal hydroxylase L1 (UCHL1)], although such cases do not produce Lewy bodies. These studies highlight critical cellular proteins and mechanisms for dopamine neuron survival as disrupted in Parkinson's disease. Understanding the genetic variations impacting on dopamine neurons may illuminate other molecular mechanisms involved. Additional candidate genes involved in dopamine cell survival, dopamine synthesis, metabolism and function, energy supply, oxidative stress, and cellular detoxification have been indicated by transgenic animal models and/or screened in human populations with differing results. Genetic variation in genes known to produce different patterns and types of neurodegeneration that may impact on the function of dopamine neurons are also reviewed. These studies suggest that environment and genetic background are likely to have a significant influence on susceptibility to Parkinson's disease. The identification of multiple genes predisposing to Parkinson's disease will assist in determining the cellular pathway/s leading to the neurodegeneration observed in this disease. 相似文献
44.
Calogero Iacono Giuseppe Verlato Giuseppe Zamboni Aldo Scarpa Ettore Montresor Paola Capelli Luca Bortolasi Giovanni Serio 《Journal of gastrointestinal surgery》2007,11(5):578-588
Objective To evaluate the prognostic significance of different clinico-pathological and molecular factors, and to compare survival after
standard and extended pancreaticoduodenectomy (PD) in ampulla of Vater adenocarcinoma (AVAC).
Summary Background Data There are discordant data on factors affecting prognosis, and hence therapeutic choices, in AVAC.
Patients and Methods Clinical-pathological factors were evaluated in 59 patients, subjected to PD for AVAC; in 42 subjects information on chromosome
17p and 18q allelic losses (LOH) and microsatellite instability (MSI) was also available. The association between survival
and type of PD was investigated in the 25 patients operated between 1990 and 2001 (16 standard and nine extended).
Results The overall 5- and 10-year tumor-related survival rates were 46% and 33%, respectively. Sixteen patients had T-stages 1–2,
14 T-stage 3, and 29 T-stage 4 cancers. Chromosome 17p and 18q LOH were detected in 23 (55%) and 15 cases (36%), respectively,
and in 12 cases (29%) coexisted. Five cases were MSI-positive (12%). At univariate analysis, poor survival was associated
with cancer ulceration (P = 0.051), poor differentiation (P = 0.008), T-stage 4 (P < 0.001), nodal metastases (P = 0.004), chromosome 17p (P < 0.001) and 18q LOH (P = 0.002), and absence of MSI (P = 0.009). At multivariate analysis, only T-stage (P = 0.002) and 17p LOH (P = 0.001) were independent predictors of survival. All patients with MSI-positive cancers were long-survivors (>12 yrs), whereas
only 30% of MSI-negative cancer patients survived at 5 years. Extended pancreaticoduodenectomy was associated with a 3-year
disease-related survival higher than standard resection (83% vs 31%; P = 0.018).
Conclusion MSI and chromosome 17p status allow to better define prognosis within ampullary cancers at the same stage. Surgery alone resulted
curative in MSI-positive cancer patients, whereas it was inadequate in patients showing allelic losses, who might benefit
from adjuvant therapy. In this observational study, extended PD was associated with increased survival compared to standard
procedures.
Presented at the 2006 Annual Meeting of the American Hepato-Pancreato-Biliary Association, Miami Beach, Florida, March 9–12,
2006 相似文献
45.
Recent studies show comparable results of arthroscopic shoulder stabilization techniques compared with the gold standard open Bankart reconstruction. Great technical advances and ever-increasing surgeon experience have rendered pathology once deemed an indication for open surgery as treatable by arthroscopic means. With this movement toward a more universal application of all-arthroscopic techniques, we might consider the following question: Is there ever a need to open? To answer this question, we must first consider normal anatomy and then appreciate the contribution of deranged pathoanatomy to recurrent instability in each individual case. The surgeon must then determine whether this is best addressed via an arthroscopic or open technique. Arthroscopy, as compared with open stabilization procedures, holds the potential benefits of decreased morbidity rates, early functional rehabilitation, and improved range of motion. Despite potential advantages, arthroscopic stabilization is clearly contraindicated when a significant pathologic lesion contributing to recurrent instability cannot be adequately addressed as a result of the limitations of current techniques or instrumentation. On the basis of this principle, we believe that sizable glenohumeral bone defects remain the only absolute contraindication to an all-arthroscopic approach. Many complicating issues, such as attenuated capsule, humeral avulsion of the glenohumeral ligament lesions, cases of revision surgery, and collision or contact athletes, exist and warrant close attention. We prefer to think of these situations as “challenges” for which both arthroscopic and open surgery should be considered, rather than as true contraindications to arthroscopic shoulder stabilization. We are, by no means, advocating arthroscopic treatment in all cases of shoulder instability, because this would represent a gross oversimplification of the issues at hand. However, we do acknowledge that the steadfast contraindications to arthroscopic shoulder stabilization are decreasing every day. 相似文献
46.
中国汉族人群腓骨肌萎缩症Cx32基因突变分析 总被引:7,自引:0,他引:7
Charcot Marie Tooth (CMT)diseaseisthemostcommoninheritedperipheralneuropathywithapreva lenceof 1in 2 5 0 0 .Distalmuscleweaknessandatro phy ,sensorylossandreducedorabsenttendonreflex es ,pescavus ,hammertoes ,steppagegaitareamongthemainsymptoms .Thereares… 相似文献
47.
目的 :探讨微卫星不稳定性 (MSI)在胃癌及肠化组织中的发生规律及其在胃癌发生过程中的作用。方法 :对 30例胃癌、4 0例肠上皮化生的石蜡标本分别提取病变及相应正常组织的DNA ,应用银染PCR SSCP技术检测 5个微卫星位点的不稳定性。结果 :胃癌组织MSI的发生率为2 3 3% ,胃窦癌MSI的发生率显著高于贲门癌 (P =0 0 4 4 )。肠化组织MSI发生率 2 0 % ,MSI全部出现在中度以上肠化组织中 (P =0 0 13) ,且更多见于女性 (P =0 0 4 4 )。结论 :MSI是胃癌多步骤发生过程中的早期分子事件 ,在胃癌的发生中可能具有重要作用。 相似文献
48.
K. Bak 《Scandinavian journal of medicine & science in sports》1996,6(3):132-144
Competitive swimming is one of the most demanding and time-consuming sports. Swimmers at elite level practice 20–30 h per week. During 1 year's practice, the average top level swimmer performs more than 500,000 stroke revolutions per arm. These innumerable repetitions over many years of hard training together with an increasing muscular imbalance around the shoulder girdle seem to be the main etiological factors in the development of the overuse syndrome swimmer's shoulder. Shoulder pain in swimmers has in general been regarded as synonymous with coracoacromial impingement, i.e. anterior shoulder pain due to rotator cuff tendinitis, but new knowledge suggests that a concomitant glenohumeral instability plays an additional role. The diagnostic complexity of the problem is as challenging as the search for the gold standard of treatment. The condition should ideally be diagnosed as early as possible, and intensive functional rehabilitation of the shoulder girdle including the scapular muscles should be started in order to restore muscle balance. The surgical possibilities include subacromial decompression in cases of purely mechanical impingement. If a painful glenohumeral instability persists after intensive functional rehabilitation, anterior capsulolabral reconstruction can be performed. Still, however, short- and long-term results show that surgery is less successful in elite athletes involved in overhead sports. Prevention protocols include education of coaches in primary injury prophylaxis and the institution of resistance strength training in prepubescent swimmers. Emphasis should be made to improve muscular balance around the glenohumeral and scapulothoracic joints. 相似文献
49.
David G. Wilder 《American journal of industrial medicine》1993,23(4):577-588
This work is a review of the mechanical factors related to low back pain production in a vibration environment. The sitting posture is an extreme orientation for the lumbar intervertebral disc that 1) increases its internal pressure, 2) increases its anteroposterior shear flexibility, while: 3) decreasing its resistance to buckling instability and 4) stressing the posterior region of the disc. Vibration is an additional mechanical stressor. Several studies suggest that the following preventive measures be taken to reduce the risk of low back pain due to driving: 1) minimize the vibration reaching the driver, 2) avoid lifting or bending immediately following driving, and 3) walk around for a few minutes following driving. © 1993 Wiley-Liss, Inc. 相似文献
50.
The fixation of a distally ruptured ulnar collateral ligament of the MP 1 (Metacarpophalangeal) joint without a portion of ligament which can be sutured or a small bony fragment can be accomplished with a variety of methods, most of which require drillholes through borth cortices and a counter incision as well as the removal of the material at a second stage [1, 11, 13, 15]. The Mitek bone mini anchor (Ethicon-Mitek®) proved to be a reliable and quick alternative [10, 12, 16, 18, 19]. It was successfully used in eleven patients with excellent stability of the reconstructed joint. 相似文献