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991.
Adhesion molecules in lymphoma metastasis 总被引:4,自引:0,他引:4
E. Roos 《Cancer metastasis reviews》1991,10(1):33-48
Summary Recently, many surface proteins of lymphoid cells that mediate adhesion to other cells and extracellular matrix have been identified. Several of these cellular adhesion molecules (CAM) are also expressed by metastatic lymphoma cells and may mediate adhesion to tissue components during the metastatic process. Correlations observed between expression of certain CAM, like MEL-14 and CD44, and particular patterns of spread, support this notion, but conclusive evidence is scarce.We have used T-cell hybridomas to study the mechanisms of wide-spread lymphoid metastasis. The results obtained with this model are reviewed here. The advantages are that a large number of genetically similar cell lines can be generated, which can be grouped in large panels of highly invasive and non-invasive cells. Invasiveness of these cells in hepatocyte and fibroblast monolayers correlates with exprimental metastasis.Lymphoid CAM that are potentially involved in metastasis are reviewed. Several of these CAM are not, or not consistently, expressed by the invasive T-cell hybridomas, indicating that they are not indispensable. Notably, some of the CAM involved in the onset of an immune response or in migration into inflamed tissues, like ICAM-1 and VLA-4, and the homing receptors MEL-14 and LPAM-1 do not seem to be involved. CAM that are consistently expressed by the T-cell hybrids include LFA-1, the beta-1 integrin subunit CD29, CD31 (PECAM-1) and CD44 (Hermes homing receptor).We have generated considerable evidence that LFA-1 is required for efficient metastasis of T-cell hybrids, based on the behavior of LFA-1-deficient mutants and revertants. High levels of LFA-1 are required. The relevant counterstructure is probably ICAM-2 rather than ICAM-1. Preliminary results suggest that also a beta-1 integrin, possibly VLA-5, plays a role. Finally, we summarize evidence indicating that CD31 and CD44 are primary candidates for involvement in metastatic spread of T-cell hybridomas. 相似文献
992.
目的 探讨不放液巩膜外加压治疗视网膜脱离手术的适应证.方法 回顾分析83例(85只眼)增生性玻璃体视网膜病变﹙proliferative vitreoretinopathy,PVR)C2级以下孔源性视网膜脱离(rhegmatogenous retinal detachment,RRD)行不放液的巩膜外加压术临床资料,分析视网膜解剖复位率、术后视力和手术并发症.83例患者术后随访时间3~48个月,平均9.2个月.结果视网膜复位79只眼,手术成功率为92.9%.PVRA级、B级、 C1级及 C2级视网膜复位率比较其差异无统计学意义(P>0.05).手术并发症为3.5%,术后视力进步73只眼,占85.9%.结论 只要掌握好手术的适应证,不放液的巩膜外加压手术成功率高,手术并发症少,术后视力恢复快,适合于非复杂性视网膜脱离. 相似文献
993.
Ching-Chang Chen Peng-Wei HsuTai-Wei Erich Wu Shih-Tseng LeeChen-Nen Chang Kuo-chen WeiChih-Cheng Chuang Chieh-Tsai WuTai-Ngar Lui Yung-Hsin HsuTzu-Kang Lin Sai-Cheung LeeYin-Cheng Huang 《Clinical neurology and neurosurgery》2009
Objective
Stereotactic biopsy is a widely used surgical technique for the histological diagnosis of intracranial lesions. Potential risks of this procedure, such as hemorrhage, seizure, and infection have been established, and different risk factors have been characterized. However, these risks have been addressed by only few studies conducted in Asian countries.Materials and methods
The study group is comprised of 299 consecutive stereotactic biopsy procedures by 11 neurosurgeons between 2004 and 2007. The pre-operative medical conditions, methods of biopsy and postoperative complications were analyzed.Result
The overall diagnostic yield was 90.64%. Complications were observed in 7.36% of the cases, with symptomatic hemorrhages occurring in 4.35% of the cases, and the overall mortality rate in this study population was 1.34%. Patients with liver cirrhosis were at a higher risk of hemorrhage. Other clinical, radiological, or histological variables were not associated with an increased risk of complications.Conclusion
Stereotactic brain biopsy is a safe and reliable way to obtain a histological diagnosis. Based on our recent clinical experiences, the data suggests that more attention should be paid to liver cirrhotic patients, since the chance on hemorrhage is significantly larger. 相似文献994.
Overview Excess spasticity leads to disability that is marked by impaired locomotion, handicapping deformities and, if not controlled,
discomfort and pain. Selective peripheral neurotomy in the child is indicated for severe focal spasticity, when botulinum
toxin injections cannot delay surgery any longer.
Materials and methods Preoperative motor blocks mimicking the outcome of the surgical procedure are essential to establish the objectives of neurotomy.
In the lower limb, obturator neurotomy is indicated for spasticity in the adductor muscles, hamstring neurotomy for the knee flexion and tibial
neurotomy for the spastic foot. Anterior tibial neurotomy is indicated for the extensor hallucis spasticity and femoral neurotomy
for spasticity in the quadriceps. In the upper limb, neurotomy of the pectoralis major and teres major nerves is indicated for spasticity of the internal rotators of the shoulder.
Neurotomy of the musculocutaneous nerve is indicated for spasticity of the flexors of the elbow, and neurotomy of median and
ulnar nerves are indicated for spasticity of the pronators and flexors of the wrist and fingers.
Conclusion Selective peripheral neurotomy is a valuable neurosurgical procedure in well-trained surgical hands for severe focalised spasticity. 相似文献
995.
J. Heidrich P. U. Heuschmann P. Kolominsky-Rabas A. G. Rudd C. D. A. Wolfe 《European journal of neurology》2007,14(3):255-261
Valid classification of stroke is essential to initiate effective acute management and early secondary prevention strategies. To accurately evaluate stroke subtype a number of diagnostic procedures have to be performed. This study sought to investigate variations in use of diagnostic procedures across selected European hospitals. First-ever stroke patients were sampled over a 1-year period through 11 hospital-based registers across 10 European countries. We defined a diagnostic standard for valid aetiological classification of ischemic stroke including brain imaging, vascular imaging and echocardiography. The impact of socio-demographic, clinical and structural characteristics on performance of the diagnostic standard was assessed using multivariate logistic regression analyses. A total of 1721 patients were included in the study. 83.1% received brain imaging, ranging from 32.8% to 100%. The diagnostic standard was performed in 40.4% of stroke patients, ranging from 0% to 77.2%. Patients with increasing age ( P < 0.001) and with more severe strokes ( P = 0.001) were less probably to receive the diagnostic standard. Patients treated in stroke units and neurological departments were more frequently investigated with the diagnostic standard ( P < 0.001). Less than half of hospitalized stroke patients across Europe underwent diagnostic procedures to allow for aetiological classification of stroke, which may hamper the initiation of effective early management and secondary prevention. 相似文献
996.
Björn Fischler Jan F Svensson Antal Nemeth 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(10):1600-1602
Aim: To study the impact of ongoing cytomegalovirus (CMV) infection at presentation of biliary atresia (BA) on the long-term outcome after Kasai procedure.
Methods: Twenty-eight patients with BA born 1988–1997 were included and followed-up until 2007. Eleven patients (group A) had ongoing CMV infection at presentation and were compared to the remaining 17 patients (group B). Median age at Kasai procedure was 75 days in group A and 70 days in group B (p = 0.12).
Results: Including all patients, survival with native liver was 50% and 36% at 4 and 10 years of follow-up respectively. At the end of follow-up, it was 25% and overall survival was 68%. When comparing groups A and B, neither difference in survival with native liver (p = 0.67, log-rank test) nor in survival after liver transplantation was detected.
Conclusion: Survival with native liver after Kasai procedure is comparable to that of other centres. CMV positive patients may present with a later onset, alternatively the detection of CMV infection could delay the referral of BA patients. No significant differences in long-term outcome were detected with regard to early CMV infection. 相似文献
Methods: Twenty-eight patients with BA born 1988–1997 were included and followed-up until 2007. Eleven patients (group A) had ongoing CMV infection at presentation and were compared to the remaining 17 patients (group B). Median age at Kasai procedure was 75 days in group A and 70 days in group B (p = 0.12).
Results: Including all patients, survival with native liver was 50% and 36% at 4 and 10 years of follow-up respectively. At the end of follow-up, it was 25% and overall survival was 68%. When comparing groups A and B, neither difference in survival with native liver (p = 0.67, log-rank test) nor in survival after liver transplantation was detected.
Conclusion: Survival with native liver after Kasai procedure is comparable to that of other centres. CMV positive patients may present with a later onset, alternatively the detection of CMV infection could delay the referral of BA patients. No significant differences in long-term outcome were detected with regard to early CMV infection. 相似文献
997.
MIKE THOMAS PhD MA BSc RMN RNT Cert Ed CELIA HYNES MA RGN RSCN RNT RCNT 《Journal of nursing management》2009,17(5):523-531
998.
手术室护士应重视无瘤技术的护理配合 总被引:1,自引:1,他引:0
无瘤操作技术是指在恶性肿瘤根治手术中,既要彻底根除恶性肿瘤,又要防止术中癌细胞沿血行转移、淋巴道扩散、创面种植等造成的医源性扩散的一项操作技术,它与无菌操作技术同等重要,但往往容易被操作者忽视,因此加强无瘤观念,认真进行护理配合是提高恶性肿瘤手术根治率的重要保障。我科在多年的无瘤技术的护理配合工作中,认真配合每一例恶性肿瘤的根治手术,无瘤技术的护理配合也日趋完善,现总结如下。 相似文献
999.
A.A. Sazgar M. Sadeghi A.K. Yazdi L. Ojani 《International journal of oral and maxillofacial surgery》2009,38(11):1210-1211
Nasoalveolar cysts are uncommon nonodontogenic and developmental cysts with an uncertain pathogenesis. This cyst has been reported to occur bilaterally in 10–11% of cases. This case report describes a 45-year-old woman in whom the clinicopathologic findings were consistent with bilateral nasoalveolar cysts. The authors report a new, less invasive method for transnasal endoscopic marsupialization of bilateral nasoalveolar cysts. Transnasal endoscopic marsupialization has benefits for the treatment of bilateral and unilateral nasoalveolar cysts. 相似文献
1000.
Comparative studies on the irritation potential of 18 surfactants were performed using the same stock solution of surfactant for each study. The ocular irritation potential of surfactants was studied using the red blood cell test (RBC), the hen's egg test-chorioallantoic membrane (HET-CAM) and the Skinethic ocular tissue model. The skin irritation potential was assessed based on data obtained from human studies using a 24h epicutaneous patch test (ECT) and a soap chamber test (SCT). The same pH and active substance (AS) content for all surfactants tested was used depending on the test conducted. In general, clusters of substances with varying irritation potential were identified similarly by most tests. These results show that when using standardized test conditions in which pH and % AS are the same for each surfactant tested, there is a good correlation between the in vitro ocular irritation assays themselves as well as between the dermal and ocular irritation assays. In particular the RBC test seems to be not only highly predictive for ocular irritation (H(50)/DI) but also for dermal irritation and changes in barrier function (DI) induced by surfactants. 相似文献