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91.
T Kyrklund 《American journal of industrial medicine》1992,21(1):15-24
The nervous system differs from many other body organs by its central control of vital functions and its low regeneration capacity. Organic solvents have, as a group, been suspected to have neurotoxic effects. Because of their similar physical properties and the fact that in industrial uses, they are often present in various mixtures, organic solvents have also been regarded, unfortunately, to induce common neurotoxic effects. However, it is evident from experimental studies using specified exposure conditions that different organic solvents have very diverse neurotoxic effects and also that the toxic mechanism may differ between acute and chronic exposure. No specific method used to describe a neurotoxic effect or single toxic response can be used for the overall occupational risk assessment of all organic solvents. Each solvent has to be considered as having its own unique toxic effects. 相似文献
92.
Sumie Yamanaka Masanori Hashimoto Masuo Tobe Kazuo Kobayashi Jun Sekizawa Masao Nishimura 《Archives of toxicology》1990,64(4):262-268
We proposed a simple method for screening assessment of acute oral and dermal toxicity using only three rats and mice of each sex at each dose level. Animals were first treated with chemicals at a dose of 2000 mg/kg and were carefully observed for compound-related morbidity and mortality. If none of the animals died, the following toxicity tests were suspended. If some of the animals died, toxicity tests at doses of 200 and 20 mg/kg were performed. The approximate LD50 values calculated by this method showed little difference between two separate laboratories and were in good agreement with LD50 values reported in the literature. Our toxicological data also showed that LD50 values were about 2–2.5 times the MNLD (maximum non lethal dose) in acute oral and dermal toxicity. This meant that a chemical could be regarded as having an LD50 of about 4000 mg/kg or higher when there was no mortality at the dose of 2000 mg/kg. A chemical with such low toxicity would not require further testing for lethal effects. Therefore, this simple method combining the fixed-dose procedure with the limit test is suitable for determination of approximate LD50 values of chemicals and for screening for necessity for classical full LD50 test using many animals.This work was supported by a grant from Ministry of Health and Welfare in Japan (No. 467 and 511) 相似文献
93.
Manoussos M. Konstadoulakis MD Michael Vezeridis MD Emi Hatziyianni MD Constantine P. Karakousis MD PhD Bernard Cole PhD Kirby I. Bland MD Harold J. Wanebo MD 《Annals of surgical oncology》1998,5(3):253-260
Background: Oncogenes and other molecular tumor markers that predict tumor aggressiveness may allow individualization and optimization of surgical therapy of intermediate-thickness malignant melanoma. We examined the expression of selected markers, including the HLA-DR antigen, the heat shock protein-70 (HSP-70), and the c-myc oncogene in primary melanoma and regional nodes and related these findings to metastatic potential and survival.
Methods: Forty patients with primary melanoma (1.5–4.0 mm) were studied, all of whom had prophylactic lymph node dissection and were followed for 18 months to 7 years. The primary tissue and nodes were examined using immunohistochemical techniques for the presence of HLA-DR antigen and HSP-70 protein and the expression of the c-myc oncogene.
Results: Of 40 patients, there were 23 with lesions 1 to 2.9 mm thick and 17 with lesions 3 to 4 mm thick. Nodal metastases were present in 25 of the 40 patients who had elective node dissection. HLA-DR antibody stained the primary tumor in 10 patients (25%), but there was no correlation with survival in this group. HLA-DR antibody stained the stroma and cellular infiltrates surrounding the primary tumor in 28 of 40 patients; in this group there was a correlation of HLA-DR staining of the peritumoral stroma with improved survival overall. HLA-DR staining of the peritumoral stroma also influenced survival when patients were stratified by tumor thickness groups 1 to 2.9 mm and 3 to 4 mm and presence of nodal metastases. HSP-70 was demonstrated in the primary tumor in 25% of patients, who were also shown to have significantly improved survival when compared with those whose primary tumor did not stain with HSP-70. C-myc was expressed in the primary tumor in 25%, but showed no correlation with survival. None of these proteins correlated with or predicted the presence of nodal metastases.
Conclusion: We conclude that the use of specific molecular-oncogene markers in intermediate-thickness primary melanoma may identify patients at high risk for conventional treatment failure and reduced survival who may profit from more aggressive surgery, adjuvant therapy, or both.Presented at the 48th Annual Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995. 相似文献
94.
95.
非霍奇金淋巴瘤85例临床及预后分析 总被引:3,自引:0,他引:3
目的:分析多种因素对非霍奇金淋巴瘤(NHL)预后的影响。方法:通过SABC法进行免疫分型,采用Kaplan—Meier法分析患者治疗后的生存期,采用Cox比例风险模型分析影响预后的因素。结果:B细胞来源-NHL(B-NHL)发病率为63.3%。T细胞来源-NHL(T—NHL)为36.7%;低度恶性占17.6%,中、高度恶性占74.1%。1、2、3、5年生存率:低度恶性患者为92.1%、84.5%、65.1%、45.1%;中、高度恶性患者为84.9%、67.5%、47.6%、28.4%。I、Ⅱ期患者为98.8%、91.5%、87.5%、70.3%;Ⅲ期、Ⅳ期患者为62.1%、55.5%、40.1%、23.8%。T—NHL为70.8%、53.5%、47.7%、30.2%;B-NHL为82.1%、70.5%、61.1%、50.1%。结论:年龄、乳酸脱氢酶水平、恶性程度、临床分期、免疫分型、身体状况评分(PS)是影响NHL预后的重要因素。 相似文献
96.
基于临床流程功能需求的生理监测仪配置评估 总被引:1,自引:0,他引:1
病人生理监测仪是临床医学的主要仪器之一,由于所涉及的技术流程定位不同,功能需求也就不同,其功能配置也应有所不同。本文从分解分析生理监测仪相关应用领域的技术定位功能需求出发,讨论卫生技术装备管理的功能配置评估。 相似文献
97.
August Colenbrander 《Acta ophthalmologica. Supplement》2010,88(2):163-173
This article, based on a report prepared for the International Council of Ophthalmology (ICO) and the International Society for Low Vision Research and Rehabilitation (ISLRR), explores the assessment of various aspects of visual functioning as needed to document the outcomes of vision rehabilitation. Documenting patient abilities and functional vision (how the person functions) is distinct from the measurement of visual functions (how the eye functions) and also from the assessment of quality of life. All three areas are important, but their assessment should not be mixed. Observation of task performance offers the most objective measure of functional vision, but it is time‐consuming and not feasible for many tasks. Where possible, timing and error rates provide an easy score. Patient response questionnaires provide an alternative. They may save time and can cover a wider area, but the responses are subjective and proper scoring presents problems. Simple Likert scoring still predominates but Rasch analysis, needed to provide better result scales, is gaining ground. Selection of questions is another problem. If the range of difficulties does not match the range of patient abilities, and if the difficulties are not distributed evenly, the results are not optimal. This may be an argument to use different outcome questions for different conditions. Generic questionnaires are appropriate for the assessment of generic quality of life, but not for specific rehabilitation outcomes. Different questionnaires are also needed for screening, intake and outcomes. Intake questions must be relevant to actual needs to allow prioritization of rehabilitation goals; the activity inventory presents a prototype. Outcome questions should be targeted at predefined rehabilitation goals. The Appendix cites some promising examples. The Low Vision Intervention Trial (LOVIT) is an example of a properly designed randomized control study, and has demonstrated the remarkable effectiveness of vision rehabilitation. It is hoped that further similar studies will follow. 相似文献
98.
99.
保留后方韧带复合体在胸腰椎骨折治疗中的意义 总被引:1,自引:1,他引:0
[目的]探讨保留后方韧带复合体在胸腰椎骨折治疗中的意义。[方法]1998~2002年单一节段胸腰椎爆裂骨折治疗中保留后方韧带复合体44例,同期行胸腰椎爆裂骨折治疗切除后方韧带复合体者35例。两种方法分别有15例(定义为A组)和12例(定义为B组)行2次手术取出内固定物,比较AB两组间2次手术前后腰椎功能JOA评分。[结果]2次手术前腰椎功能JOA评分:A组平均24.5分(19~29分);B组平均22.8分(19~29分),二者无显著性差异(P〉0.05)。2次手术后JOA评分:A组平均24.8分(20~29分),B组平均17.5分(13~26分)。二组有显著性差异(P〈0.05)。[结论]胸腰椎骨折治疗中保留后方韧带复合体,利于术后腰椎功能恢复。 相似文献
100.
Katherine Patterson Corinna Young Steven Paul Woods Ofilio Vigil Igor Grant J. Hampton Atkinson 《International journal of methods in psychiatric research》2006,15(2):75-82
Major Depressive Disorder (MDD) is among the most prevalent but underdiagnosed psychiatric disorders in persons with HIV infection. Given the known adverse impact of comorbid MDD on HIV disease progression and health‐related quality of life, it is important both for research and for efficient, effective clinical care, to validate existing screening measures that may discriminate between MDD and the somatic symptoms of HIV (such as fatigue). In the current study, we evaluated the concurrent predictive validity of the Profile of Mood States (POMS) Depression‐Dejection scale in detecting current MDD in 310 persons with HIV infection. The Structured Clinical Interview for DSM‐IV (SCID) diagnosis of MDD and the Cognitive‐Affective scale from the Beck Depression Inventory (BDI‐CA) served as comparative diagnostic and severity measures of depression, respectively. Results demonstrated that the POMS Depression‐Dejection scale accurately classified persons with and without MDD SCID diagnoses, with an overall hit rate of 80%, sensitivity of 55%, specificity of 84%, and negative predictive power of 91% using a recommended cutpoint of 1.5 standard deviations above the normative mean. Moreover, the POMS performed comparably to the BDI‐CA in classifying MDD. Findings support the predictive validity of the POMS Depression‐Dejection scale as a screening instrument for MDD in persons with HIV disease. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献