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1.
L Lehtola H Lehv?slaiho P Koskinen K Alitalo 《Acta oncologica (Stockholm, Sweden)》1992,31(2):147-150
As the factor binding to the neu protein has been unknown, it has not been possible to confirm experimentally the proposed growth-factor receptor like functions of the neu protein. To approach this problem we constructed a recombinant receptor which enabled ligand regulation of the neu tyrosine kinase. The hybrid receptor consisted of the extracellular ligand binding, transmembrane and protein kinase C-substrate domains joined to the intracellular tyrosine kinase and carboxyl-terminal domains of the neu protein. Several properties of NIH3T3 cells carrying this construct were tested. We obtained the first experimental evidence that the neu proto-oncogene has mitogenic and transforming activities only in the presence of a ligand stimulating its tyrosine kinase activity. Various cellular and molecular biological parameters indicated that the chimeric receptor behaved very similarly to the EGFR. Also, this chimeric receptor has allowed us to compare the constitutive oncogenic and the ligand-activated non-oncogenic activities of the neu tyrosine kinase. In the future we plan to focus on characterization of possible differences between EGFR and neu signalling in more differentiated cellular backgrounds. 相似文献
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Localized pleural plaques and lung cancer. 总被引:1,自引:0,他引:1
T Partanen M Nurminen A Zitting H Koskinen M Wiikeri K Ahlman 《American journal of industrial medicine》1992,22(2):185-192
In a mass chest radiography survey conducted in 1971 for 7,986 residents of three Finnish communities, 604 subjects (7.6%) with pleural plaques but not other asbestos-related radiographic signs were identified. The same number of referents, each individually matched to each plaque carrier on sex, birth year, and community, was selected from among persons in the same source population with no pleural plaques. The two groups were followed for investigation of incidence of lung cancer during 1972-1989. Twenty-eight of those with plaques and 25 referents contracted lung cancer (crude conditional RR = 1.1; CL95 = 0.7, 1.9). The application of the proportional hazards model, with adjustment for sex, age, and residence, resulted in a hazard ratio of 1.1 (CL = 0.6, 1.8). The risk ratio estimate may be biased; hence, the result is inconclusive in regard to the predictive assessment of lung cancer risk among carriers of pleural plaques. 相似文献
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Gennadi Naumov Elena Naumova Hilkka Turakainen Pirkko Suominen Matti Korhola 《Current genetics》1991,20(4):269-276
Summary We used a combination of genetic hybridization analysis and electrokaryotyping with radioactively labelled MEL1 gene probe hybridization to isolate and identify seven polymeric genes for the fermentation of melibiose in strain CBS 5378 of Saccharomyces cerevisiae (syn. norbensis). Four of the MEL genes, i.e. MEL3, MEL4, MEL6 and MEL7, were allelic to those found in S. cerevisiae strain CBS 4411 (syn. S. oleaginosus) whereas three genes, i.e. MEL8, MEL9 and MEL10 occupied new loci. Electrokaryotyping showed that all seven MEL genes in CBS 5378 were located on different chromosomes. The new MEL8, MEL9 and MEL10 genes were found on chromosomes XV, X/XIV and XII, respectively. 相似文献
6.
Marja Hilska Yrj? Collan Peter J Roberts Jari Ovaska Jyrki K?ssi Hannu Paajanen Matti Laato 《Acta chirurgica》2002,168(2):84-90
OBJECTIVE: To compare the ability of various methods of staging and grading to predict survival in proximal colon cancer. DESIGN: Retrospective study. SETTING: University hospital, Finland. SUBJECTS: 153 patients with primary proximal colon cancer. MAIN OUTCOME MEASURES: Staging by four classification systems, grading by two grading systems, and survival analysis based on Kaplan-Meier survival curves. RESULTS: In all staging systems the survival curves of different stages differed significantly from each other. The modified Dukes' classification was still the best predictor of survival. Grade of tumours had no significant effect on long term survival, but short term survival was affected adversely by the presence of anaplastic tissue. Tumours with no mucin had a worse prognosis than those that produced mucin. All staging methods were superior to either of the histological grading systems tested as prognosticators. Tumour depth correlated with the operator's clinical impression of radicality of operation, and also predicted survival. CONCLUSION: The clinicopathological modified Dukes' staging system was the most powerful prognosticator in proximal colonic cancer and its use in clinical practice should continue. Even a small amount of anaplastic tissue (> or = 5%) had an adverse effect on short term survival. 相似文献
7.
目的 通过对已报道的全膝关节置换翻修术文献进行总结分析,讨探膝关节置换翻修术前后的膝关节功能、翻修的主要原因、主要并发症及不同假体的术后疗效.方法 按照以下标准收集和分析有关全膝关节置换翻修术的文献:①1990年至2002年间发表,②报告患者数大于10例,③采用通用的膝关节评分标准.一名骨科专科医生独立收集数据,一名医学统计学专家独立采用Meta统计方法分析数据.结果 共有33 篇符合条件的文献被收集.患者共1356 例,其中男429例,女611例(部分文献性别分类数据缺失),平均年龄67岁(45~49岁),加权平均随访时间57个月( 6~108 个月),加权平均术前膝关节功能总评分为49 分(15~94分),术后为84分( 58~109分),全膝关节置换翻修术前后的总评分、功能评分、活动范围等有显著性提高,差异有统计学意义(总评分t=12.507,P<0.01, 功能评分t=4.704,P<0.01,活动范围:t=5.346,P< 0.01).全膝关节置换翻修术的原因主要是假体松动(55%),其它包括聚乙烯磨损(11%)、假体不稳(10%)、感染(7%).翻修术后的主要并发症仍然为假体松动(18%),其它包括假体不稳(16% )、感染(16% )、髌骨问题( 15% )及不明原因的膝关节疼痛(13%).髌骨问题包括髌骨脱位、半脱位、髌韧带撕裂、髌股关节疼痛等.结论 可以认为膝关节置换后翻修术是一种安全有效的手术.假体松动是膝关节置换翻新的主要原因和并发症. 相似文献
8.
Ari Mennander Jari Laurikka Pekka Kuukasj?rvi Matti Tarkka 《European journal of cardio-thoracic surgery》2005,27(1):32-34
OBJECTIVE: To assess the impact of postoperative continuous pleural lavage (PCPL) after thoracotomy for the treatment of stage 2 pleural empyema in relation to postoperative length of stay and morbidity. METHODS: Stage 2 pleural empyema was diagnosed with computer tomography. Conservative treatment including antibiotics and pleural aspiration was introduced. 89 patients treated for stage 2 pleural empyema by thoracotomy, pleural discharge evacuation and irrigation after pleural decortication were identified after unsuccessful conservative treatment for 10 days. Whenever pleural discharge remained opaque after operation, PCPL was administered daily through the cranial chest tube and discharge evacuated through the caudal pleural suction (10-15 mmHg) tube. Risk factors related to pleural pus and patient outcome were sought for. RESULTS: Seventy-seven out of 89 patients (86.5%) had clear empyema discharge immediately after pleural decortication and irrigation. Pleural discharge remained opaque despite surgery in 12 out of 89 patients (13.5%) and PCPL was introduced. Presence of a combination of risk factors for pleural empyema, such as dental caries, alcohol abuse or previous inflammatory reaction, was predictive for persistence of opaque pleural discharge after operation (P<0.05). Need for re-thoracotomies (in 11 cases, P=ns) and postoperative deaths (P<0.05) were related with patients who did not have PCPL. The length of the hospital treatment was 20.1+/-3.1 (days+/-SEM) among patients with PCPL and 19.2+/-1.8 without PCPL before possible re-thoracotomy, respectively (P=ns). CONCLUSIONS: Early postoperative (1 day-11 months) mortality was statistically associated with patients having fibrinopurulent empyema but no PCPL. PCPL is a feasible method to clear pleural pus discharge without prolongation of hospitalization and may be recommended after thoracotomy for patients with fibrinopurulent stage 2 empyema. 相似文献
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P Oksa H Koskinen J P Rinne A Zitting P Roto M S Huuskonen 《American journal of industrial medicine》1992,21(4):561-567
Exposure to mineral dust was studied among construction workers (N = 437) with the aid of a questionnaire and a chest X-ray examination of the lungs. The results of the questionnaire showed that 81% of the construction workers had been exposed to asbestos. Exposure had occurred in all of the occupational groups studied. Pleural plaques and/or lung fibrosis (ILO greater than or equal to 1/1) were found in 26% of the examined workers; the prevalence varied from 18 to 40% among the various occupational groups. Comparison with a representative sample of the Finnish male population from another investigation indicates that the frequency of lung fibrosis (ILO greater than or equal to 1/1) is at least two times higher among the examined construction workers than among the general population. It seems likely that exposure to asbestos dust can be considered an etiological factor for an appreciable number of the X-ray findings. 相似文献