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51.
Teenagers' health concerns: implications for primary health care professionals. 总被引:3,自引:4,他引:3 下载免费PDF全文
Four hundred and eighty five students, aged 13-15 years, at nine comprehensive schools in the London borough of Brent completed a questionnaire about health-related behaviours and health concerns. Among general health concerns, most prominent were weight, acne, nutrition and exercise. There appeared to be a considerable unmet need to discuss sexual development, sexually transmitted diseases and contraception. A substantial proportion (16% of the girls and 3% of the boys) reported sexual abuse, but few wished to discuss this with a doctor or nurse. Although a relatively high percentage of the students smoked and a smaller percentage used alcohol or drugs regularly, there was little concern or interest in discussing these matters with a health professional. Most of the schools did not have a formal health education programme, and in none of them were health professionals available for discussion of the issues under study. There appears to be a need for more comprehensive health education in schools and for primary health care professionals, particularly general practitioners to raise these issues opportunistically with their teenage patients. 相似文献
52.
B K Hecht A L Epstein C S Berger H S Kaplan F Hecht 《Cancer Genetics and Cytogenetics》1985,14(3-4):205-218
Cell lines were established from 15 patients with diffuse histiocytic lymphoma (DHL) of the intermediate grade, diffuse large cell (class G), and high-grade, large cell immunoblastic (class H) types. Immunologic studies indicated that 11 of the 15 DHL cell lines were B cell in origin, 2 were histiocytic, and 2 were null cell. Cytogenetic studies revealed 1 hypodiploid, 11 hyperdiploid, and 3 near-tetraploid cell lines. Chromosome #7 was trisomic in 3 lines, chromosomes #12 in 4 lines, and chromosome #13 in 3 lines. Chromosome #2 was monosomic in 3 lines, chromosome #8 was monosomic in 5 lines, chromosome #14 in 4 lines, and chromosome #22 in 6 cell lines. This is of special interest, as chromosomes #2, #8, #14, and #22 are clearly concerned with rearrangements in Burkitt's lymphoma and immunoglobulin expression. The most common rearrangement in the DHL cell lines involved chromosome #14 at band 14q32. However, in contrast to Burkitt's lymphoma, the pattern of translocation in DHL is between chromosome #14 and usually chromosome #11 or chromosome #18. The 14;18 translocation is not restricted to patients with low-grade follicular, small cleaved cell lymphomas, as has been reported. The 14q+ chromosome is characteristic of lymphoid malignancies in general. It is due, invariably, to a translocation with the breakpoint in band 14q32, which is the locus of the immunoglobulin heavy chain genes. We propose that in each translocation, for example, chromosomes #11 or #18, an oncogene may be transposed onto chromosome #14, and that each 14q+ translocation in DHL represents an event that transposes an oncogene from another chromosome to chromosome #14. 相似文献
53.
Prostate Stem Cell Compartments : Expression of the Cell Cycle Inhibitor p27Kip1 in Normal, Hyperplastic, and Neoplastic Cells 总被引:6,自引:4,他引:6 下载免费PDF全文
Angelo M. De Marzo Alan K. Meeker Jonathan I. Epstein Donald S. Coffey 《The American journal of pathology》1998,153(3):911-919
The stem cells of rapidly renewing tissues give rise to transiently proliferating cells, which in turn give rise to postmitotic terminally differentiated cells. Although the existence of a transiently proliferating compartment has been proposed for the prostate, little molecular anatomical evidence for its presence has been obtained to date. We used down-regulation of the cyclin-dependent kinase inhibitor p27Kip1 to identify cells capable of entering the proliferative phase of the cell cycle and, therefore, competent to fulfill the role of the transiently proliferating compartment. We examined the expression of p27Kip1 in relation to its role in the development of prostatic carcinoma. Formalin-fixed paraffin-embedded specimens from matched samples of normal-appearing prostate tissue, benign prostatic hyperplasia, high-grade prostatic intraepithelial neoplasia, primary adenocarcinomas, and pelvic lymph node metastases were evaluated by comparative immunohistochemistry against p27Kip1. In normal-appearing prostate epithelium, moderate to strong nuclear staining of p27Kip1 was present in greater than 85% of the terminally differentiated secretory cells. The normal basal cell compartment, believed to contain prostatic stem cells, showed distinctive p27Kip1 expression; acini in epithelial benign prostatic hyperplasia tissue contained more p27Kip1-negative basal cells than acini from non-benign prostatic hyperplasia tissue. A third layer of cells was identified that was sandwiched between the basal cells and the luminal cells, and this layer was consistently p27Kip1 negative. This intermediate layer was accentuated in the periurethral region, as well as in prostate tissue that had been subjected to prior combined androgen blockade. We hypothesize that, on appropriate additional mitogenic stimulation, cells in this layer, and other p27Kip1-negative basal cells, are competent for rapid entry into the cell cycle. Consistent with the fact that cancer cells are capable of cell division, all cases of high-grade prostatic intraepithelial neoplasia and invasive carcinoma also showed down-regulation of p27Kip1 as compared with the surrounding normal-appearing secretory cells. In pelvic lymph node metastases, p27Kip1 expression was also reduced. In summary, our results suggest that lack of nuclear p27Kip1 protein may delineate a potential transiently proliferating subcompartment within the basal cell compartment of the human prostate. In addition, these studies support the hypothesis that reduced expression of p27Kip1 removes a block to the cell cycle in human prostate epithelial cells and that dysregulation of p27Kip1 protein levels may be a critical early event in the development of prostatic neoplasia. 相似文献
54.
Milk intake and nipple attachment behaviors were studied in the natural suckling situation after gastrointestinal preloading. Rat pups, deprived of their dam for 9 hr at 1, 10, or 20 days of age, were preloaded by gavage with volumes ranging from 2 to 16% of their body weight and returned to suckle. Preloads of artificial bitch's milk decreased the intake of mother's milk in a volume-related manner at all ages. At 1 and 10 days 4% preloads decreased milk intake without affecting attachment behaviors; larger prelods of 8 and 16% decreased intake and reduced the incidence of attachment. At 20 days of age small and large preloads decreased both incidence of attachment and milk intake. Preloads up to 8% of body weight had no effect on latency to attach at any age. Complete subdiaphragmatic bilateral vagotomy increased milk intake of 7–9–day-old pups fed automatically through an anterior mouth cannula in a nonsuckling situation. Vagotomy combined with spinal cordotomy (T2-T3) resulted in a synergistic hyperphagia and massive distension of the upper GI tract. The results indicate that suckling rats can control their intake of mother's milk while remaining attached to a nipple as early as 1 day of age. The suppression of ingestion in response to GI filling appears to be mediated by visceral afferent activity. Conversely, attachment behaviors are less affected by GI fill. This suggests that ingestive behaviors and attachment behaviors have different controls during the 1st 10 days of postnatal development. 相似文献
55.
Willis F Graff-Radford N Pinto M Lawson L Adamson J Epstein D Parfitt F Hutton M O'Brien PC 《Journal of the National Medical Association》2003,95(1):71-76
Through its role in lipid metabolism, Apolipoprotein epsilon4 (ApoE4) may affect "brain repair" in stroke, brain hemorrhage, Alzheimer's disease, and other brain injury syndromes for which African Americans may have greater morbidity and mortality. Cross-cultural evaluations of these and other genetic factors may provide insight on possible ethnic differences in risk of morbidity to acute central nervous system (CNS) injury and chronic neurodegenerative processes. As an initial step toward expanding knowledge of ApoE allele frequencies for persons of African descent, we compared ApoE genotype of a group of 70 young Ugandans to 59 (subset of a larger group of 342 African Americans of all ages) age-matched African Americans and to published frequencies for Caucasians and Asians. We found that the ApoE4 and epsilon2 alleles are more frequent in Ugandans (U) than Caucasians (C) or Asians (A) with corresponding alleles showing significant elevations of epsilon2 (U 15.71%, C 8.40%, A 4.20%) and 14 (U 25%, C 13.70%, A 8.90%) (p < .001). Comparing the differences between Ugandans and age-appropriate African Americans (AA) was not statically significant, but this outcome may be due to small sample size. These results provide the only published ApoE frequencies for Ugandans and the complete set of data provides the largest published community group of ApoE frequencies for African Americans. 相似文献
56.
Cysteine protease and its inhibitor in experimentally produced squamous cell carcinomas in hairless mouse skin 总被引:1,自引:0,他引:1
R Alidina M Kikuchi M Kashima J H Epstein K Fukuyama 《Experimental and molecular pathology》1988,49(1):118-127
Squamous cell carcinomas (SCC) were experimentally produced in hairless mouse skin, and cysteine protease and its inhibitor were simultaneously purified from extracts of 1 g of tissue of SCC and normal skin. Activity of cysteine proteinases, Mr greater than 50,000 and Mr 28,000, increased in SCC compared to those in normal skin. SCC also showed elevation of cysteine proteinase inhibitor activity and Mr 13,000 and Mr 82,000 inhibitors were purified. Mr 13,000 inhibitor was found to have biochemical properties which were the same as those of the inhibitor present in normal skin. Mr 82,000 inhibitor was not detectable in normal skin and it differed from a serum inhibitor with a similar Mr in terms of activity and stability at acidic pH. The findings suggest that the increased activity of both cysteine proteases and endogenous inhibitors may be involved in the regulatory mechanisms of malignant cell metabolism and tissue remodeling associated with SCC development. 相似文献
57.
Carlson EC Audette JL Veitenheimer NJ Risan JA Laturnus DI Epstein PN 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,271(2):332-341
Capillary basement membrane (CBM) thickening is an ultrastructural hallmark in diabetic patients and in animal models of diabetes. However, the wide variety of tissues sampled and diverse methods employed have made the interpretation of thickness data difficult. We showed previously that acellular glomerular BMs in OVE26 transgenic diabetic mice were thickened beyond normal age-related thickening, and in the current study we hypothesized that other microvascular BMs likewise would show increased widths relative to age-matched controls. Accordingly, a series of tissues, including skeletal and cardiac muscle, ocular retina and choriod, peripheral nerve, lung, pancreas, and renal glomerulus was collected from 300-350-day-old normal and transgenic mice. Transmission electron micrographs of cross sections through capillary walls were prepared, and CBM thickness (CBMT) was determined by the "orthogonal intercept" method. Morphometric analyses showed highly variable transgene-related BMT increases in the sampled tissues, with glomerular BM showing by far the greatest increase (+87%). Significant thickness increases were also seen in the retina, pulmonary alveolus, and thoracoabdominal diaphragm. BMT increases were not universal; however, most were modestly widened, and those that were thickest in controls generally showed the greatest increase. Although the pathogenesis of diabetes-related increases in CBM is poorly understood, data in the current study showed that in OVE26 transgenic mice increased BMT was a frequent concomitant of hyperglycemia. Accordingly, it seems likely that hyperglycemia-induced microvascular damage may be a contributing factor in diabetic BM disease, and that microvessel cellular and extracellular heterogeneity may limit the extent of CBM thickening in diverse tissues. 相似文献
58.
M D Rifkin E A Zerhouni C A Gatsonis L E Quint D M Paushter J I Epstein U Hamper P C Walsh B J McNeil 《The New England journal of medicine》1990,323(10):621-626
BACKGROUND. In 1987, a cooperative study group consisting of five institutions was formed to determine the relative benefits of magnetic resonance imaging (MRI) and endorectal (transrectal) ultrasonography in evaluating patients with clinically localized prostate cancer (stage Ta or Tb). METHODS. Over a period of 15 months, 230 patients were entered into the study and evaluated with identical imaging techniques. We compared imaging results with information obtained at the time of surgery and on pathological analysis. RESULTS. MRI correctly staged 77 percent of cases of advanced disease and 57 percent of cases of localized disease; the corresponding figures for ultrasonography were 66 and 46 percent (P not significant). These figures did not vary significantly between readers; moreover, simultaneous interpretation of MRI and ultrasound scans did not improve accuracy. In terms of detecting and localizing lesions, MRI identified only 60 percent of all malignant tumors measuring more than 5 mm on pathological analysis and ultrasonography identified only 59 percent. CONCLUSIONS. The MRI and ultrasonography equipment that is currently available is not highly accurate in staging early prostate cancer, mainly because neither technique has the ability to identify microscopic spread of disease. Further evaluation with improved equipment may improve the accuracy of these techniques. 相似文献
59.
O Epstein B Arborgh M Sagiv R Wroblewski P J Scheuer S Sherlock 《Journal of clinical pathology》1981,34(10):1071-1075
In primary biliary cirrhosis (PBC) liver copper retention occurs as a complication of cholestasis. By analogy with Wilson's disease, it has been suggested that copper retention is hepatotoxic in PBC, and this has been the rationale for the use of D-penicillamine in this disease. The hypothesis that copper is hepatotoxic in PBC has not been tested and in this study we have evaluated the role of liver copper retention in the pathogenesis of PBC. Sixty-four patients with PBC have been studied. Fifty-four had increased liver copper concentrations. Liver cell synthetic function was well preserved. All the patients had normal prothrombin times, and only two had subnormal serum albumin concentrations. There was no correlation between liver copper concentrations and the degree of liver cell damage assessed biochemically (aspartate transaminase), and histologically. Electron microscopy was performed on liver biopsies from five patients with markedly increased liver copper concentrations. The liver cell ultrastructure was compatible with cholestasis. Liver cells contained electron dense lysosomes, which were shown to contain copper and sulphur by x-ray probe microanalysis. The characteristic organelle changes associated with copper toxicity in Wilson's disease were not observed. The biochemical, histological, and histochemical differences between PBC complicated by liver copper retention, and Wilson's disease, indicates that there are differences in the handling of copper in these disease. In this study we could find no evidence to suggest that copper plays an important role in the pathogenesis of liver dysfunction in PBC. 相似文献
60.