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1.
The relationship between bladder cancer and occupational exposure to asbestos was investigated between 1978 and 1982 at La Paz Hospital in Madrid in a case-control study conducted among 353 male patients and 53 women with a diagnosis of urothelium carcinoma, and among an equal number of controls matched in age (decade of life), sex and date of admission to the hospital. The results showed that bladder cancer is associated with occupational exposure to asbestos.  相似文献   
2.
An association between the occurrence of antibodies to simian vacuolating virus 40 and bladder cancer in male smokers was found in a case-control study conducted in 200 male patients with bladder cancer and 400 control men. The risk of bladder cancer increases with the years of cigarette smoking.  相似文献   
3.
We have utilized the rat hepatoma (HTC) cell sorting variant CR4 to examine the glucocorticoid-regulated pathways that localize mouse mammary tumor virus glycoproteins to the cell surface. The defective sorting of cell surface mouse mammary tumor virus glycoproteins in CR4 cells was complemented after fusion with either normal rat hepatocytes or uninfected HTC cells. Indirect immunofluorescence of transient heterokaryons revealed that the regulated localization of mouse mammary tumor virus glycoproteins was dependent upon glucocorticoid treatment and required de novo RNA and protein synthesis. Thus, a glucocorticoid-regulated trafficking activity, unrelated to mouse mammary tumor virus sequences, which is induced in both adult rat liver and cultured hepatoma cells, can act in trans to mediate an intracellular sorting pathway for membrane glycoproteins.  相似文献   
4.
Adrenal chromaffin cells in vitro respond to nerve growth factor (NGF) by expressing neuronal traits. Low frequency magnetic (LFM) field stimulation, while inducing a variety of effects on several cell types, has never been studied as to its effects on chromaffin cell cultures. The purpose of this study was to compare the effects of LFM field stimulation with that of NGF on the morphological phenotype, on noradrenaline (NA) release, and on membrane excitability of cultured chromaffin cells. We also tested the effects of grafting LFM and NGF-treated chromaffin cells into the caudate nucleus of rats with 6-hydroxydopamine lesions of the nigrostriatal pathway. The results of this study showed that LFM field stimulation produced neurite growth of cultured chromaffin cells in a manner similar to that of NGF exposure. The combination of the two procedures did not induce changes above those observed by NGF alone. Both NGF- and LFM-treated chromaffin cells released [3H]NA equally in response to a depolarizing concentration of KCl. On the other, Na+ current density of LFM field stimulation increased, but to a lesser extent than that seen in NGF-treated cells. In addition both types of cells when transplanted into nigrostriatal-lesioned animals induced a similar decrease in the motor asymmetries produced by the lesion. When NGF- or LFM-treated chromaffin cells where compared to untreated control cells, no significant differences were observed in [3H]NA release, on Na+ current densities, or on postgraft motor asymmetries. The results are discussed in terms of the fact that LFM-stimulated cells can be differentiated in a manner similar to NGF-treated cells, by acquiring sympathetic like traits which in turn can diminish motor asymmetries when grafted into nigrostriatal-lesioned rats.  相似文献   
5.
Objective:  Prevalence of textile dye contact dermatitis (TD‐CD) are lacking in many countries. Our aim is to know the frequency of TD‐CD in three different areas of Spain.
Methods:  100 patients were tested with Spanish standard series and the five most frequent TD in each city. D. Orange 1, D. Orange 3, D. Blue 35, D. Blue 106, D. Blue 124 were included in Murcia and Seville, and the three last and D. Red 1, D. Red 17 in Santiago.
Results:  23/300 (15 women and 8 men) were positives to one or more TD. D. Blue 124 was the most frequent allergen (18/300), followed by D. Blue 106 (17/300). D. Red 1, D. Red 17 and D. Orange 1 were positives in 2/200. D. Orange 3 and D. Blue 35 were positives in 1/200. Eczema was located on hands in 13 cases. Clinical picture was variable. Origin of sensitization was clothing and occupational. Relevance was obtained in 20/23 cases.
Conclusions:  The study confirm an high frequency of disperse dye allergy in Spain with a very different prevalence in the three areas: Seville 14%, Murcia 5% and Santiago 4%, that are probably due to social and cultural factors. We recommend the inclusion of D. Blue 106, D. Blue 124, D. Blue 35, D. Red 1, D. Red 17, D. Orange 1 and D. Orange 3 in standard series in order to detect sensitivity to textile colours that is most frequent than previously suspected.  相似文献   
6.
Summary Thirty adult patients presenting with medulloblastoma between 1974 and 1991 were studied and treated at Puerta de Hierro Clinic. After diagnosis, all patients were treated by surgery followed by radiotherapy and eight of them received adjuvant chemotherapy. We have studied the influence of some factors such as age, sex, location of tumour in the cerebellum, amount of surgical resection and histological variants on survival and recurrence of the disease. Only the histological type has a statistically significant influence on survival and recurrence: we have found that patients presenting classic medulloblastoma have a long survival and a long relapse-free interval.  相似文献   
7.
This study hypothesized that family role (marital and parental status) would moderate the effect of disaster exposure on the mental health of victims. The study included St. Louis residents exposed to floods and dioxin, as well as Puerto Rican respondents exposed to floods and mudslides. In St. Louis, worst outcomes were found for single and married parents exposed to disaster, substantially exceeding the symptomatology of all unexposed respondents except non-victim single parents. In Puerto Rico, victims without families had higher levels of alcohol abuse symptoms than did any other subgroup. Perceived emotional support was found to be an important moderator of disaster's effect on psychiatric distress in this site, generally overriding the effect of family role. Single parents in both sites who were exposed to disaster had substantially reduced levels of emotional support available to them, as compared to unexposed single parents, suggesting that single parents are at particularly high risk for losing access to emotional support following a disaster. This study suggests that both single and married parents constitute important high-risk victim groups. The findings also suggest that those perceiving they lack adequate emotional support, regardless of family role, may be in special need of services.  相似文献   
8.
cDNA clones of potato virus X (PVXcp strain), potato virus Y (PVYo strain), potato leaf roll virus (PLRV) and potato spindle tuber viroid (PSTV) were used separately or combined for the detection of the corresponding RNAs in extracts of infected plants. A general method for the rapid preparation of RNA extracts without use of organic solvents (i.e. phenol) was developed for this purpose. Plant extracts from a range of field, artificially inoculated germplasm genotypes, micro-propagated and protoplast samples, as well as vector insect extracts, were dot-blotted onto nylon or nitrocellulose membranes, subjected to sandwich nucleic acid hybridization with non-labelled specific single-stranded DNA probes followed by a biotin-labelled second step hybridization probe. Each probe was virus-specific but not strain-specific. Healthy or non-related plant extracts developed very faint or no signals. Sensitivity was tested by slot-blot hybridization. Detection levels were between 1.5 to 6 pg of viral nucleic acids and between 20 to 50 times more sensitive than standard double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). The assay developed was tested with material that was prepared for processing in the field (combination of fresh sap with extraction solution) and tested under simple laboratory conditions for detection. It was also successfully employed for screening of germplasm for virus resistance, detection of pathogens in vector insects, plantlets grown in vitro and in more sophisticated quantitative determinations of viral replication in artificially inoculated plants and protoplasts.  相似文献   
9.
Ultrastructural study of testicular biopsy specimens from 67 adults with primary testicular disorders (Klinefelter's syndrome, XX male syndrome, Del Castillo's syndrome, and cryptorchidism) revealed the following four Leydig cell types: 1) normal or nearly normal Leydig cells with abundant smooth endoplasmic reticulum, mitochondria with tubular cristae, lipid droplets, and Reinke's crystals; 2) abnormally differentiated Leydig cells without either lipid droplets or Reinke's crystals but with altered mitochondria, concentric unfenestrated cisternae of smooth endoplasmic reticulum, and both paracrystalline and filamentous inclusions; 3) multivacuolated Leydig cells containing abundant lipid droplets; and 4) immature Leydig cells with scarce development of the smooth endoplasmic reticulum and mitochondria, and numerous cytoplasmic microfilaments. Abnormally differentiated Leydig cells might represent dysgenetic cells, whereas immature, normal, and vacuolated Leydig cells might represent three progressive stages in the Leydig cell cycle (undifferentiated, mature, and old involuting Leydig cells). An inverse correlation between the proportion of abnormal Leydig cells and testosterone levels was observed in each of these testicular disorders.  相似文献   
10.
Community-academic partnerships in the training of doctors offer unique learning opportunities of great importance. Such partnerships can induce a paradigm shift such that physicians view community as a teaching resource and partner rather than as a passive recipient of services or solely as a placement site. The authors describe a model of a community-academic partnership in New York City, begun in 1995, in which, for training and service, pediatric residents are integrally involved in a community-based program. Principles adapted from the Community-Campus Partnerships for Health's principles of partnership provide a framework for portraying the essential elements of developing and maintaining the partnership. The authors explain the clashes that may arise between partners and show how the principles of partnership guide partnership members in working and learning within a setting that by its nature entails conflict and inequality. This report is based on the knowledge gained from the structured reflections of both members of this partnership: the residency program at a large academic health center and the community-based social service organization. Such partnerships provide the training ground for the development of physicians who understand the social and cultural determinants of health and constructively use community agencies' input in promoting child health and well-being. Within this framework, community-based organizations are not solely service providers but become educators of physicians-in-training who, with new knowledge gained through the partnership, more effectively contribute to the overall health of the communities they serve.  相似文献   
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