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1.
Dermatologists, employers, insurance carriers and patients often flounder in misunderstanding when dealing with industrial dermatosis. A large part of such misunderstanding stems from too limited a knowledge of compensation insurance law by physicians, employee-patients and many employers. Physicians dealing with industrial cases should not only familiarize themselves with compensation law and insurance practices, but take it upon themselves to interpret such considerations to their employee-patients and, where necessary, to their patients' employers. Present-day employer-employee relationships are frequently on a most impersonal basis, and great mutual benefit will accrue to all parties when the position and objectives of each are understood by the others and the provisions and limitations of the law are known to all. The dermatologist handling industrial cases must take the responsibility of bringing this about.  相似文献   

2.
Understanding how tumor cells manage to survive and proliferate in ever-changing and often harmful microenvironments is a daunting challenge in tumor biology, and a major cause of treatment failure in the oncology clinic. Recent data have now demonstrated a direct link between the molecular chaperone Hsp90 and survivin, a dual regulator of cell proliferation and cell death over-expressed in virtually every human tumor. While the survivin-Hsp90 association may help tumor cells elevate their anti-apoptotic threshold and promote their proliferation, it may also provide new opportunities for rational cancer therapy.  相似文献   

3.
The impact of tumor markers on the outcome of several malignancies is still under debate. This relative uncertainty leads to a subjective approach to their use. Monitoring the use of tumor markers is a valuable tool to identify the need for educational policies. We conducted a survey to evaluate how tumor markers are routinely used in the follow-up of patients with breast, colorectal and ovarian carcinoma. The former two malignancies are considered in the present paper. We surveyed 35 Italian hospitals; 29 (83%, accounting for 26,622 hospital beds) filled in and returned the questionnaire. Overall, 467,361 tumor marker requests were scrutinized by the surveyed hospitals. We found a wide variability in the type and number of routinely used markers, the cutoff points chosen, and the clinical decisions taken on the basis of marker results. In addition, we observed a relative lack of communication between clinicians and clinical pathologists in around 50% of the surveyed hospitals. In these cases clinical information was not provided to the laboratory and methodological aspects were not communicated to clinicians. From the findings of the present study we conclude that the cooperation between clinicians and clinical pathologists must improve before guidelines for the use of tumor marker assays can be framed and the compliance with these guidelines can be checked. Request forms for tumor marker assays should therefore be designed to contain clinical information and the quality of filling in request forms with clinical data should be carefully monitored.  相似文献   

4.
Sean A. Rands 《Evolution》2010,3(4):633-640
The conceptual understanding of the process of adaptation (whereby a population becomes better suited to its environment over evolutionary time) is acknowledged to be a difficult one. Many studies have shown that there is an inherent misunderstanding of the term, which is often related to the learner adopting the common rather than biological usage of the term in the learner’s language. But understanding adaptation is essential to understanding evolution, and learners need to be encouraged to understand how to relate hypotheses of the “function” of a trait shown by an individual with the environment in which the individual lives. Here, I describe a practical which encourages a class of learners to create their own organisms, through a series of steps by which they create functional explanations of morphology and behavior. Using a branching process whereby groups of students are split into smaller and smaller subgroups, an artificial phylogeny is created. A wiki system is then used to emphasize how individual species and groups of species are related. The relationship of this practical to problems of tree-thinking is discussed.  相似文献   

5.
While specific genes are hypermethylated in the genome of cancer cells, overall methylcytosine content is often decreased as a consequence of hypomethylation affecting many repetitive sequences. Hypomethylation is also observed at a number of single-copy genes. While global hypomethylation is highly prevalent across all cancer types, it often displays considerable specificity with regard to tumor type, tumor stage, and sequences affected. Following an overview of hypomethylation alterations in various cancers, this review focuses on 3 hypotheses. First, hypomethylation at a single-copy gene may occur as a 2-step process, in which selection for gene function follows upon random hypo methylation. In this fashion, hypomethylation facilitates the adaptation of cancer cells to the ever-changing tumor tissue microenvironment, particularly during metastasis. Second, the development of global hypomethylation is intimately linked to chromatin restructuring and nuclear disorganization in cancer cells, reflected in a large number of changes in histone-modifying enzymes and other chromatin regulators. Third, DNA hypomethylation may occur at least partly as a consequence of cell cycle deregulation disturbing the coordination between DNA replication and activity of DNA methyltransferases. Finally, because of their relation to tumor progression and metastasis, DNA hypomethylation markers may be particularly useful to classify cancer and predict their clinical course.  相似文献   

6.
Rapidly detectable and easily accessible markers of tumor cell death are needed for evaluating early therapeutic efficacy for immunotherapy and chemotherapy so that patients and their physicians can decide whether to remain with a given therapeutic strategy. Currently, image-based tests such as computed tomography scans and magnetic resonance imaging are used to visualize the response of a patient’s tumor, but often these evaluations are not conducted for weeks to months after treatment begins. While serum levels of secreted proteins such as carcinoembryonic antigen and prostate specific antigen are commonly monitored to gauge tumor status during therapy and between image evaluations, the levels of these proteins do not always correlate well with the actual tumor response. In laboratory studies, it has been shown that tumor cells undergoing apoptosis can release cellular components into cell culture media such as cytochrome c, nucleosomes, cleaved cytokeratin-18 and E-cadherin. Studies of patient sera have found that these and other macromolecules can be found in circulation during cancer therapy, providing a potential source of material for monitoring treatment efficacy. In the future, analysis of biofluids from severe combined immunodeficiency mice bearing patient tumor specimens treated with a targeted therapy such as Apo2L/tumor necrosis factor-related apoptosis-inducing ligand will be useful in the preclinical identification of therapy response markers. In this review, the current status of the identification of serum markers of tumor cell apoptosis is provided, as well as a discussion of critical research questions that must be addressed and the considerations necessary when identifying a marker that reflects true clinical outcome.  相似文献   

7.
Moldvay J 《Magyar onkologia》2000,44(3):195-202
Primary bronchial cancer is the most common cause of cancer death worldwide, and it shows a steadily increasing incidence. Beside classical histological typing and grading, immunohistochemical, cytometric, and molecular biological parameters are highly needed to assist light microscopy investigations to better characterize primary bronchial cancers. In this work the author summarizes the main tumor markers and prognostic factors in lung cancer studied intensively at present. Serum markers as well as different tissue markers, such as cell proliferation markers, oncogenes, growth factors, apoptosis markers and vascularisation markers, tumor suppressor genes and markers of drug resistance are discussed in details. The methods currently used in this field are also mentioned and the data of the literature is often completed with results of the author's own investigations. An overview is given about the role of tumor markers in the early detection of lung cancer, in the assessment of tumor aggressiveness, and in therapy of lung cancer. The aim of this work is to create a bridge between the research laboratory in which lung cancer is studied sometimes using very sophisticated techniques and the bedside with all its practical, difficult but very important questions. Getting closer the theory and the practice can be very promising in the establishment of a fruitful collaboration in order to be more effective in the fight against lung cancer.  相似文献   

8.
This article explores how song operates as a forum through which Alsatian Manouches (a subgroup of Romanies/“Gypsies”) negotiate social relations with non-Manouches and with each other. Two of the most salient identity markers for Manouches are music and language. Whereas Manouches regard instrumental music as a legitimate means of engaging with non-Manouche people, it is often considered inappropriate to share their spoken dialect of Romani with others. As a combination of both, Manouche song represents a complex juncture of volition and apprehension towards their interactions with non-Manouches. Drawing on fieldwork among Manouche and non-Manouche performers, I investigate how public Manouche vocal performance ironically connotes an ambivalence towards cross-cultural sharing, and how power relations unfold through varying degrees of linguistic concealment and openness. This article theorizes the (il-)legibility of the voice in music and illustrates how song reflects Manouche language ideologies in flux.  相似文献   

9.
MicroRNAs are an abundant class of noncoding RNAs, typically 20-23 nucleotides in length that are often evolutionarily conserved in metazoans and expressed in a cell and tissue specific manner. MicroRNAs exert their gene regulatory activity primarily by imperfectly base pairing to the 3' UTR of their target mRNAs, leading to mRNA degradation or translational inhibition. In cancer, microRNAs are often dysregulated with their expression patterns being correlated with clinically relevant tumor characteristics. Recently, microRNAs were shown to be directly involved in cancer initiation and progression. This review focuses primarily on emerging developments in the microRNA field that impact our understanding of how these molecules contribute to carcinogenesis.  相似文献   

10.
In Western countries a considerable number of older people move to a residential home when their health declines. Institutionalization often results in increased dependence, inactivity and loss of identity or self-worth (dignity). This raises the moral question as to how older, institutionalized people can remain autonomous as far as continuing to live in line with their own values is concerned. Following Walker's meta-ethical framework on the assignment of responsibilities, we suggest that instead of directing all older people towards more autonomy in terms of independence, professional caregivers should listen to the life narrative of older people and attempt to find out how their personal identity, relations and values in life can be continued in the new setting. If mutual normative expectations between caregivers and older people are not carefully negotiated, it creates tension. This tension is illustrated by the narrative of Mr Powell, a retired successful public servant now living in a residential home. The narrative describes his current life, his need for help, his independent frame of mind, and his encounters with institutional and professional policies. Mr Powell sees himself as a man who has always cared for himself and others, and who still feels that he has to fulfil certain duties in life. Mr Powell's story shows that he is not always understood well by caregivers who respond from a one-sided view of autonomy as independence. This leads to misunderstanding and an underestimation of his need to be noticed and involved in the residential community.  相似文献   

11.
Although the International Federation of Gynecology and Obstetrics officially changed the classification system of endometrial cancer from a clinically staged to a surgically staged disease in 1988, optimal management of patients with endometrial cancer is still controversial. Gynecologists happen to experience that patients with tumors that are identical in grade and stage often have significantly different clinical outcomes or responses to therapy. In order to identify an objective biological factor correlating with tumor aggressiveness, many tumor markers have been investigated. So far, CA125 is one of the most reliable tumor marker for adenocarcinoma of the uterus and frequently used in a clinical setting. Recently, with the advent of molecular biological techniques, many genes and regions of the genome related to endometrial cancer have been identified. We undertook a genome-wide screening to detect genetic changes by comparative genomic hybridization (CGH) in primary endometrioid cancers, since CGH analysis provides comprehensive information concerning relative chromosomal losses and gains in tumors by a single hybridization. In this paper, the usefulness of serum tumor markers and the new promising molecular tumor markers for endometrial cancer are discussed.  相似文献   

12.
In this article three approaches to define and explain negative ethnic attitudes are discussed: the anthropology of cultural misunderstanding, the sociology of how differences in group positions are justified ideologically, and the social psychology of maintaining self‐esteem through intergroup differentiation. The‐ aim is to integrate these approaches into an interdisciplinary model. Social identity theory is used as a frame for this integration. The argument developed is that ingroup values are used for intergroup differentiation and evaluation. This leads to the development of stereotypes. Stereotypes reflect misunderstanding, but also anchor social representations of a hierarchy of group positions (ethnic hierarchy). Depending on the ethnic composition of the larger society, majority and minority groups will differ in their ethnic hierarchies. Discrepancies between ethnic hierarchies will lead to ethnic tension. From the perspective developed, a number of hypotheses is derived about how changes in the socio‐economic position of minority groups will affect intergroup evaluations. Hypotheses based on the category differentiation model and the social identity model are specified with respect to the expected changes in stereotypes and intergroup discrimination of the ethnic majority and minority groups.  相似文献   

13.
One of the most important challenges in contemporary oncology is to find objective biomarkers of tumor aggressiveness, which help to identify more invasive phenotypes of the carcinoma. The purpose of this study was to investigate the relationships between the early and the late activation markers expression on T CD4(+) and CD8(+) cells subpopulations and certain clinicopathological characteristics of the neoplastic infiltration in order to determine their role as biomarkers for tumor behavior in squamous cell laryngeal carcinoma. Analysis of the early (CD69(+), CD71(+)) and the late activation antigens (CD25(+) (high), CD26(+), HLA/DR(+)) expression on T CD4+ and CD8(+) lymphocytes by cytofluorymetry in 55 patients treated for squamous cell laryngeal carcinoma was performed. Clinicomorphological analysis on the basis of TNM criteria and tumor front grading, which included tumor-related features and adjacent stroma-related characteristics of the peripheral edge of infiltration was carried out. The relationships between the activation markers expression and parameters of tumor aggressiveness were investigated. Our work revealed statistically significant differences in the expression of the studied activation markers on T cells with regard to certain clinicomorphological features. The expressions of CD69(+) and CD71(+) antigens on T CD3(+)CD4(+) and CD3(+)CD8(+) cells as well as CD4(+)HLA/DR(+) markers were higher for pT3 and pT4 tumors, in comparison with pT2 carcinomas. Moreover, tumors with the smallest number of TFG points were characterized by significantly lower values of the average expression of CD3(+)CD69(+) and CD3(+)CD71(+) as well as CD4(+)HLA/DR(+) markers on T lymphocytes. In addition, more aggressive and deeply infiltrating laryngeal carcinomas were most often characterized by significantly higher values of the average expression of CD69(+) and CD71(+) antigens on CD8(+) as well as HLA/DR(+) markers on CD4(+). Our study confirmed the implication of the early and the late activation antigens expression on CD4(+) and CD8(+) T lymphocytes in clinicomorphological parameters of the tumor, especially TFG total score and depth of invasion, and their importance as indicators of the invasive phenotype of laryngeal carcinoma.  相似文献   

14.
Oral squamous cell carcinoma (OSCC) is the most common type of head and neck cancer. Epithelial dysplasia is often initiated in the cells and cell nuclei adjacent to the epithelial cell membrane. Reduced cell–cell adhesions enable cancer cells to detach from the tumor and disseminate to other organs. The mutations in epithelial dysplasia markers such as E‐cadherin and epithelial cell adhesion molecules (CD326) can lead to proliferation, growth and survival of the tumor cells and persistence of numerous malignancies that play a key role in epithelial dysplasia of OSCC. Accordingly, these genes can be considered prognostic markers or potential therapeutic targets for the tailored management of patients with OSCC. The gene expression profile of OSCC stem cells indicates a differential pattern that facilitates establishing a cell signature. Owing to the highly tumorigenic behavior of cancer stem cells and the role of these cells in tumor differentiation, treatment resistance, relapse, and metastasis, we reviewed the role of stem cell markers in epithelial dysplasia and OSCC.  相似文献   

15.
microRNAs (miRNAs) are implicated in carcinogenesis and their expression in biological fluids offer great potential as nucleic acid markers for cancer detection and progression. Authors investigated the expression level of miRNAs (miRNA-21, miRNA-126, and miRNA-155) to evaluate their role as diagnostic and prognostic markers for breast cancer compared with other commonly used protein-based markers (CEA and CA15-3). Serum samples from patients with breast cancer (n = 96), patients with benign breast lesion (n = 47), and healthy individuals (n = 39) were enrolled for detection of miRNA expression levels and protein-based tumor markers using fluorescent real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Correlation among investigated markers with clinicopathological factors and clinical outcomes were determined. Expression of miRNA-21 and miRNA-155 revealed significant increases in patients with breast cancer compared with both benign and control groups, the same result was reported for tumor markers; on the other hand, miRNA-126 was significantly decreased in breast cancer group as compared with the other two groups. miRNA frequencies were significantly related to clinical staging and histological grading as compared with tumor markers. Patients with breast cancer with increased miRNA-21 and miRNA-155 and decreased miRNA-126 expressions had significantly worse disease-free survival, while only miRNA-21 and miRNA-126 showed poor OS (P< 0.005). In conclusion, investigated miRNAs were superior over tumor markers for the early stage of breast cancer especially those with high-risk factor and their assessment in blood facilitates their role as a potential prognostic molecular marker.  相似文献   

16.
17.
An appraisal of the widely implemented clinic practice of weighing babies to monitor their physical well being showed that these weighing practices are often inadequately administered through faulty weighing techniques, insufficient use of centile charts, and misunderstanding of normal variations in, and nutritional influences on, early weight gain. If measurements of weight are accurate and the counts of weight gain plotted on centile charts and the resulting profile sensibly interpreted it becomes a valuable method of monitoring health. Possibly the greatest benefit is that the mothers have the opportunity to discuss any anxieties about the baby''s health.  相似文献   

18.
19.
Glioblastoma (GBM) is the most malignant primary brain tumor, with an average survival rate of 15 months. GBM is highly refractory to therapy, and such unresponsiveness is due, primarily, but not exclusively, to the glioma stem-like cells (GSCs). This subpopulation express stem-like cell markers and is responsible for the heterogeneity of GBM, generating multiple differentiated cell phenotypes. However, how GBMs maintain the balance between stem and non-stem populations is still poorly understood. We investigated the GBM ability to interconvert between stem and non-stem states through the evaluation of the expression of specific stem cell markers as well as cell communication proteins. We evaluated the molecular and phenotypic characteristics of GSCs derived from differentiated GBM cell lines by comparing their stem-like cell properties and expression of connexins. We showed that non-GSCs as well as GSCs can undergo successive cycles of gain and loss of stem properties, demonstrating a bidirectional cellular plasticity model that is accompanied by changes on connexins expression. Our findings indicate that the interconversion between non-GSCs and GSCs can be modulated by extracellular factors culminating on differential expression of stem-like cell markers and cell-cell communication proteins. Ultimately, we observed that stem markers are mostly expressed on GBMs rather than on low-grade astrocytomas, suggesting that the presence of GSCs is a feature of high-grade gliomas. Together, our data demonstrate the utmost importance of the understanding of stem cell plasticity properties in a way to a step closer to new strategic approaches to potentially eliminate GSCs and, hopefully, prevent tumor recurrence.  相似文献   

20.
Tumor development is critically dependent on the formation of a supporting stroma consisting of neovasculature, inflammatory cells and activated fibroblasts. Activated fibroblasts present a heterogeneous cell population not only in regard to the expression of marker molecules but also to their origin and molecular signaling properties. The plasticity of this cell type is pointed out by the multiple transdifferentiation events that lead to the generation of activated fibroblasts which can arise from resting fibroblasts, epithelial and endothelial cells as well as from mesenchymal stem cells. Cellular in vitro and in vivo experiments have changed the perspective of fibroblasts from passive “bystanders” in the tumor microenvironment to that of important drivers of tumor progression. Here, we describe the multiple origins of fibroblast recruitment to the tumor tissue as well as the function of activated fibroblasts during tumor initiation, progression, metastasis and anti-VEGF resistance. The identification of markers present in activated fibroblasts as well as a better understanding how these cells influence other tumor compartments has led to the clinical development of anti-tumor therapies.  相似文献   

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