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21.
Type IV collagenases in invasive tumors   总被引:11,自引:0,他引:11  
Summary The matrix metalloproteinases appear to be elevated in tumors with metastatic potential, and may well be involved in penetration of the basement membrane and degradation of extracellular proteins including type IV collagen. An imbalance between the 72 kDa and 92 kDa type IV collagenases and the associated tissue inhibitors of these metalloproteinases (TIMPs) may therefore have a role in the invasive phenotype. Cultured tumor cells with invasive potential secrete both type IV collagenases, though in tumors there is some evidence that the 72 kDa form at least may be produced by stromal cells at the invading tumor front rather than primarily by the tumor cells themselves, while the 92 kDa form may be synthesized in macrophages near the front. These collagenases are elevated in invasive as compared within situ tumor components, but their specific roles and prognostic significance are not yet established.  相似文献   
22.
The cosmetic results of the breast (144 patients)were analysed after segmental resection and axillary dissectionwith or without postoperative radiotherapy for early low-riskbreast cancers. Cosmetic results were assessed over time(3, 9, 18, 36, 48 months respectively) bythe patient and by the physician. Patients ratedthe overall cosmetic result good or excellent in92% of cases after 3 months. The proportionof good or excellent cosmetic results decreased overtime and after four years 89% of patientsclassified themselves in this category, whereas the physicianassessed the outcome as good or excellent in91% of cases after 3 months and 75%after 4 years. The inter-observer consistency between physicianand patient in assessing the cosmetic outcome was=0.42 at the beginning and decreasedover time (=0.07 after 4 years).The intra-observer variation over time was =0.53 for the patient and =0.32for the physician.Inter-observer consistency between patient and physician was moderateimmediately following treatment but decreased over time. Thefeeling of satisfaction of the patient was relativelystable whereas the opinion of the physician becamesomewhat more critical over time. Therefore the intra-observerconsistency over time was somewhat better for thepatient than for the physician.  相似文献   
23.
Myocardial metabolism in exercise was determined by studying 21 syndromeX patients and 14 healthy volunteers with an aromatic fatty acid analogue IPPA and a gamma camera. We developed criteria for visual semiquantitative assessment of relative segmental radiotracer uptake and washout, and tested a new computer program for quantitative evaluation. One volunteer (7%) and 12 patients (57%) showed visually inhomogeneous uptake (p=0.006, 2-test) in SPECT polar tomograms after a maximal ergometry test. Images in none of the volunteers and seven patients (33%) gave the impression of a slowed regional washout (p=0.057). Only six patients (29%) had a normal radial polarogram. Patients with irregular coronary angiograms (showing slow flow or minor sclerosis) and those with chest pain during the IPPA exercise test had a very low frequency of normalcy, but this was not significant.Total washout was higher in patients than in the reference population, as the exercise to rest activity ratio was 1.36 SD 0.13 versus 1.25 SD 0.11 in computerized quantitation (p=0.015, t-test). Washout did not correlate with age, sex or exercise heart rate. Regarding computerized analysis of uptake and slow washout, the number of deviant segments was not significantly higher in patients than in reference population. Semiquantitative and quantitative analysis correlated in the assessment of uptake, but not in the assessment of washout. Possible reasons for the discrepancy are discussed.Conclusions of this study are not straightforward. SyndromeX was associated with inhomogeneous IPPA uptake, which is not at variance with the theory of microvascular dysfunction. On the other hand, the analysis of washout presumably implies higher fatty acid utilization in patients than in normal controls, which is not a characteristic phenomenon in myocardial ischemia.  相似文献   
24.
 In order to evaluate the effect of the introduction of recent similar guidelines on the treatment of acute urinary tract infection (UTI) in children, and possible changes in its epidemiology, we analyzed the records of hospital discharge for acute UTI under the age of 15 years in England and Wales between 1979 and 1993 and in Finland between 1978 and 1994. Cases were defined by the ICD9 diagnostic codes 590.1 (acute pyelonephritis) and 599.0 (UTI, site not specified) for males and females according to three age groups (0–4, 5–9, and 10–14 years). We also compared the registry data on kidney transplants due to end-stage renal disease caused by recurrent pyelonephritis in the United Kingdom and Finland. In England the rate of attack of symptomatic UTI per 1,000 girls under 15 years increased from 0.74 (95% confidence interval 0.71–0.76) in 1987 to 1.32 (1.29–1.35) in 1993 (P<0.001, test for trend). The respective figures for Finnish girls were 1.74 (1.62–1.86) in 1987 and 1.62 (1.51–1.74) in 1993 (P=0.72). In English boys, the increase in the attack rate was from 0.38 (0.36–0.40) in 1987 to 0.70 (0.68–0.73) in 1993 (P<0.001). In Finnish boys the respective figures were 0.74 (0.66–0.82) in 1987 and 0.88 (0.80–0.97) in 1993 (P<0.02). The observed increases in the attack rates of UTI most probably relate to increased referral of acute UTI patients to hospitals for the recommended imaging studies rather than changing occurrence. Publication of guidelines for treatment of UTI in children, consolidating more-general awareness, may have contributed to this. The mean annual numbers of kidney transplants in the United Kingdom and Finland during 1989–1995 due to end-stage renal disease caused by pyelonephritis were of similar magnitude, i.e., 1.9 (1.6–2.3) transplants per million inhabitants in the United Kingdom and 2.8 (1.5–4.7) transplants per million inhabitants in Finland. The decreasing trend in these figures in both countries, although statistically significant only in the United Kingdom (P<0.05, test for trend), suggests improved long-term outcome of these patients induced by better diagnosis and treatment of pyelonephritis and the diseases related to it, such as congenital malformations. According to our data, valid clinical guidelines are effective in changing clinical practice. Received: 1 September 1997 / Revised: 29 April 1998 / Accepted: 29 April 1998  相似文献   
25.
Nine members, MEL2–MEL10, of the MEL gene family coding for -galactosidase were physically mapped to the ends of the chromosomes by chromosome fragmentation. Genetic mapping of the genes supported the location of all the MEL genes in the left arm of their resident chromosomes.  相似文献   
26.
In response to the need for formal psychosocial assessment in childhood epilepsy, a 25-question inventory was constructed from raw items based on multidisciplinary inputs and tested for practicality, and psychometric attributes. Weighted inter-rater and test-retest reliability estimates were 61.8% and 63.9% respectively. A measure of concurrent validity was satisfactory though a modest discrepancy was observed between two raters (P = 0.019 and 0.0064). Discriminant validity was very satisfactory (average P 0.001) based on compared means of ratings from two groups of subjects with disparate prognosis. The inventory should be useful in the assessment of similar chronic childhood disabilities but interpretations of data should be in a wider clinical context including inputs of informant and school authorities as indicated.  相似文献   
27.
Objectives and Study Design: The advent of the rigid endonasal endoscope and the development of functional endoscopic sinus surgery (FESS) technique have awakened interest in an endonasal endoscopic dacryocystorhinostomy (EESC-DCR) in treating nasolacrimal obstruction. This prospective, randomized study compares EESC-DCR with traditional external dacryocystorhinostomy (EXT-DCR) for their success rates, surgical duration, and postoperative symptoms. Patients and Methods: Sixty-four cases in 60 patients with primary acquired nasolacrimal sac or duct obstruction were divided into two subgroups by symptoms (simple epiphora/ chronic dacryocystitis). These patients were randomized within both subgroups into two operation groups. Altogether 32 EESC-DCRs and 32 EXT-DCRs were performed. The final follow-up visit was at 1 year. The patency of the lacrimal passage was investigated by irrigation and patients were questioned about their symptoms. Results: The success rate at 1 year after surgery was 75% for EESC-DCR and 91% for EXT-DCR after primary surgery. The difference was not statistically significant (P = .18). The success rate after secondary surgery with a follow-up time of 1 year was 97% in both study groups. The average duration for EESC-DCR was 38 minutes, and 78 minutes for EXT-DCR, (P < .001). Conclusions: EXT-DCR, when compared with EESC-DCR, appears to give a higher, although not statistically significant, primary success rate, but the secondary success rates are equal, indicating that these two different DCR techniques are acceptable alternatives.  相似文献   
28.
Objective To evaluate the use of the pre-operative tumour-associated trypsin inhibitor (TATI) level and residual tumour size at primary surgery as a prognostic indicators for patients with Stage III epithelial ovarian cancer.
Design Retrospective cohort study.
Setting Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland.
Participants Ninety-eight women with Stage III ovarian cancer.
Methods TATI was measured by radioimmunoassay from serum samples obtained within one week before surgery. A cutoff value of 22 μg/L was used. Multivariate analysis included pre-operative TATI level, age, histologic grade and histologic type. Mantel-Cox test was used for calculating statistical significance of differences in survival between groups.
Main outcome measures Cumulative five-year survival, pre-operative serum TATI level and residual tumour size.
Results Surgery was optimal (residual tumour size ≤ 2 cm) in 55 patients and suboptimal (residual tumour size > 2 cm) in 43. Pre-operative TATI level ≤ 22 μg/L predicted better prognosis both in patients with optimal and suboptimal surgery compared with patients with pre-operative TATI level > 22 μ/L. Patients with optimal surgery and a pre-operative TATI > 22 μg/L had a twofold relative risk of death compared with those with a pre-operative TATI ≤ 22 μg/L. The cumulative survival was less than three years for patients with suboptimal surgery and pre-operative TATI > 22 μg/L.
Conclusions Pre-operative serum TATI in combination with residual tumour size may be useful in stratifying patients with Stage III ovarian cancer into different categories in randomised treatment trials.  相似文献   
29.
OBJECTIVE: We assessed the risk of prostate cancer by exposure to Chlamydia trachomatis. METHOD: Seven hundred thirty eight cases of prostate cancer and 2,271 matched controls were identified from three serum sample banks in Finland, Norway, and Sweden by linkage to the population based cancer registries. RESULTS: A statistically significant inverse association (odds ratio, 0.69; 95% confidence interval, 0.51-0.94) was found. It was consistent by different serotypes and there was a consistent dose-response relationship. CONCLUSION: C. trachomatis infection is not likely to increase the risk of prostate cancer. Whether the inverse relationship is true or due to difficulties in measuring the true exposure in prostatic tissue by serology, confounders or other sources of error remain open.  相似文献   
30.
Despite there being sufficient evidence for the effectiveness of screening by cytology in preventing cancer of the cervix uteri, screening policies vary widely among European countries, and incidence is increasing in younger women. This study analyzes trends in squamous cell carcinoma (SCC) of the cervix uteri in 13 European countries to evaluate effectiveness of screening against a background of changing risk. Age-period-cohort models were fitted and period and cohort effects were estimated; these were considered as primarily indicative of screening interventions and changing etiology, respectively. A unique set of estimates was derived by fixing age slopes to one of several plausible age curves under the assumption that the relation between age and cervical cancer incidence is biologically determined. There were period-specific declines in cervical SCC in several countries, with the largest decreases seen in northern Europe. A pattern emerged across Europe of escalating risk in successive generations born after 1930. In the western European countries, a decrease followed by a stabilization of risk by cohort was accompanied by period-specific declines. In southern Europe, stable period, but increasing cohort trends, were observed. Substantial changes have occurred in cervical SCC incidence in Europe and well-organized screening programs have been highly effective in reducing the incidence of cervical SCC. Screening and changing sexual mores largely explain the changing period- and cohort-specific patterns, respectively. The increasing risk in recent cohorts is of obvious concern particularly in countries where no screening programs are in place. Further investigation of the effectiveness of opportunistic screening is warranted as is the observation of differing risk patterns in young cohorts in countries with relatively similar societal structures.  相似文献   
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