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181.
J. Pfisterer F. Kommoss W. Sauerbrei B. Baranski M. Kiechle H. Ikenberg A. Du Bois & A. Pfleiderer 《International journal of gynecological cancer》1996,6(1):54-60
In a retrospective study the prognostic significance of nuclear DNA content was investigated, as measured by flow cytometry, of the tumor specimens from 212 women with nonpretreated FIGO stage IB and II cervical cancer. One-hundred and thirty cases (62%) were found to be diploid, whereas 82 (38%) were aneuploid. Univariate analysis of the follow-up data showed an increased relative risk (RR) for recurrence free survival (RFS) for stage II tumors (RR = 1.87, 95% CI: 1.13–3.10, P = 0.015) and for age (RR = 1.52, 95% CI: 0.66–3.52 and RR = 2.35, 95% CI: 1.19–4.65, P = 0.032). Ploidy showed a relative risk of 1.33 (95% CI: 0.83–2.13, NS). In addition, univariate analysis of overall survival (OS) revealed similar results. For the subgroup of patients with primary surgery ( n = 151), positive pelvic nodes (RR = 5.38, 95% CI: 2.70–10.71, P = 0.0001) and parametrial extension (RR = 2.53, 95% CI: 1.24–5.17, P = 0.011) were significant factors for OS after univariate analysis, the estimated effects on RFS were slightly smaller. Multivariate analysis of RFS for the whole study population showed age, histologic grade and stage with a slightly increased risk, but no effect was significant. Ploidy with an RR of 0.97 (95% CI: 0.58–1.62) seems to have no influence on prognosis. For the subgroup with primary surgery, ploidy again failed statistical significance with an RR of 1.20 (95% CI: 0.58–2.49). Our results suggest that abnormalities of the nuclear DNA content in this homogeneous group of patients are associated with clinical and morphological prognosticators, however, ploidy is not an independent prognostic factor for RFS, or for the whole study population or for the subgroup with primary surgery. 相似文献
182.
Angiogenesis in invasive breast carcinoma: is it associated with parameters of prognostic significance? 总被引:5,自引:0,他引:5
Recent experimental and clinical studies suggest that tumour-induced angiogenesis may be an important step in the evolution of malignant tumours, and may be related to prognosis. In our study we examined 42 cases of breast carcinoma (mean age: 56.76 ± 13.5), 21 with lymph node metastases and 21 without. Angiogenesis was evaluated after immunohistochemical staining of tumour vessels, using polyclonal antibody to factor VIII related antigen (VIIIR-Ag) and counting of the three most active areas of neovascularization. In the same manner we counted the microvessels in lymph node metastases. The mean vessel count of node-negative cases (51.16 ± 19.32) did not differ significantly from node-positive cases (45.66 ± 17.44). In contrast patients younger than 50 years had much higher mean vessel counts (54.04 ± 16.47) than did patients older than 70 years (38.03 ± 16.73) producing a P value of ≤0.05. No association was found between tumour size and mean vessel count, nor was there any significant difference between grade I (45.94 ± 16.54), grade II (53.13 ± 23.22) and grade III tumours (51.71 ± 20.64). When we compared the mean vessel count of primary tumours with those of node metastases, we found much lower counts in the latter ( P ≤0.01). The differences in our results from previous studies, probably reflect the heterogeneity which exists between different tumours in their ability to induce angiogenesis. Additionally, there is some evidence in our study that angiogenesis is possibly related to patient age and probably depends on differences in the tumour stroma. 相似文献
183.
184.
丁勇 《南京医科大学学报(自然科学版)》1988,(3)
介绍用Logistic 曲线来计算初潮均龄及95%可信区间,该方法只需原始数据即可进行计算,不必将来潮率以概率单位置换,从而避免了年龄与发生率的S 形曲线与正态分布函数相符这一要求。经验证和比较,认为本方法计算简便,误差小,是一种值得采用的方法。 相似文献
185.
人群归因危险度百分比 (populationattributableriskproportion ,PARP)是总体人群中某种疾病归因于某种因素的暴露所引起的发病 (死亡 )占全部发病 (死亡 )的百分比 ,反映该因素所引起的发病 (死亡 )占全部发病 (死亡 )的比重。通过PARP可了解各危险因素对人群中某疾病的发病所产生的影响 ,亦即消除某危险因素后 ,所产生的对预防该疾病的效果将占有多大比重。它能够为卫生政策的制订提供依据 ,有着重要的公共卫生的实际意义。目前常用的估计PARP的方法有两种 :一种是利用全国人群抽样调查获得的人群总暴露率来估计 ;另一种是利用某地区… 相似文献
186.
187.
Jeffrey V. Rosenfeld MS FRACS FRCS 《Journal of clinical neuroscience》1994,1(4):231-242
Great advances in neurobiology have resulted from 100 years of neural transplantation research. In the last 20 years, there has been a focus on using neural transplantation to repair the damaged central nervous system (CNS) utilising experimental animal models of various human neurodegenerative disease and CNS injury. Since 1985, there has been a rapid proliferation of adrenal medullary autograft transplantation to the caudate nucleus of humans with Parkinson's disease. However, this operation proved to be unsuccessful and was associated with unacceptable morbidity. Implantation of human fetal mesencephalon into patients with severe parkinsonism has supplanted the adrenal operation and has produced promising results, with some patients reported to improve markedly and some evidence of graft survival noted on positron emission tomography (PET). Host tissue recovery appears to be an important mechanism for this clinical improvement. The optimal technique is to use three to four fetuses from induced abortions of 6.5 to 8 weeks gestation, with multiple stereotactic implants into the putamen and caudate nucleus. Many biological questions still remain and the community remains troubled by the ethical problems of using fetal tissue obtained from abortions. This procedure is still experimental and should be restricted to a few centres with excellence in cell and molecular biology. A multicentre study is needed to more carefully evaluate CNS transplantation. Cloned neural precursor cells or immortalized embryonic cell lines genetically modified to manufacture selected growth factors or neurotransmitters may offer an alternative to the use of human fetal tissue. Much more experimental animal research is necessary before transplantation can be used to treat other CNS maladies. 相似文献
188.
Ellen A. Eisen Paige E. Tolbert Marilyn F. Hallock Richard R. Monson Thomas J. Smith Susan R. Woskie 《American journal of industrial medicine》1994,26(2):185-202
A case-control study of larynx cancer was conducted within a cohort of automobile workers exposed to metal working fluids, commonly referred to as machining fluids (MF). Results are based on 108 cases of larynx cancer and 5:1 matched controls. Risks associated with specific types of MF, as well as specific components of the fluids were evaluated. Based on a retrospective exposure assessment, lifetime exposures to straight and soluble fluids, grinding particulate, biocides, selected metals, sulfur, and chlorine were examined. Exposure to asbestos and acid mists at two of the three study sites was also characterized. Results suggest that straight mineral oils are associated with almost a two-fold excess in larynx cancer risk. There was also evidence of an association with elemental sulfur, commonly added to straight MF to improve the integrity of the materials under extreme pressure and heat. It is not clear whether sulfur is causally related to an excess relative risk of larynx cancer or whether the observed association is the result of unmeasured confounding by another contaminant or process feature. For example, the high stress operations that require MF enriched with sulfur are also more likely to produce polycyclic aromatic hydrocarbons (PAHs) during the process. Thus, the observed association with sulfur may be due to an association with PAH. The finding of excess risk of laryngeal cancer associated with MF is consistent with several previous reports in the literature. This is the first study, however, to distinguish straight mineral oils from other types of MF. Based on these findings, a general reduction in concentrations of straight mineral oil particulate in occupational environments would be prudent. 相似文献
189.
190.
The mould collection of the Centraalbureau voor Schimmelcultures, Baarn, The Netherlands, was screened for isolates originating from warm-blooded animals. The range of species indicates that distribution of clinically relevant, pathogenic or opportunistic strains over the fungal kingdom is non-random. Some opportunistic fungi possess adaptations to life under hostile environmental conditions, enabling them to survive inside the human body. Presence of melanin or carotene seems to be an important virulence factor. Opportunistic fungi which sporulate in submersion are able to disseminate or cause severe local mycoses when the aspecific immune system of the host is impaired. Mycoses caused by a few dimorphic fungi, mostly in their natural ecological niche living in association with vertebrates, are promoted by specific immune deficiencies. 相似文献