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31.
Sean Sullivan 《International journal of mental health and addiction》2007,5(4):381-389
The EIGHT Screen is a brief problem gambling screen originally designed for use by family doctors. Its wider use indicated
the need for further validation. A triangulated approach used a range of measures in different settings in both the current
study and findings from a number of earlier projects, and reviewed current use. The EIGHT Screen had acceptable correlations
with the SOGS (r = 74–90%) and with the NODS-12 months Screen (r = 62.4%). Measurements remained relatively constant amongst a range of cultures, settings, age and gender, while few false
positives were produced by the screen. The EIGHT Screen appears to be a valid tool for untrained users to identify Level 2
and 3 problem gambling in a wide range of cultures and settings. 相似文献
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The distinction between seminoma and embryonal carcinoma based on morphology alone can sometimes be problematic, requiring the use of immunohistochemistry to facilitate diagnosis. D2-40 is a monoclonal antibody that reacts with an oncofetal antigen expressed by fetal germ cells and testicular germ cell tumors. The diagnostic value of D2-40 immunohistochemistry in distinguishing seminoma from embryonal carcinoma has not been determined. D2-40 immunoreactivity was evaluated in a series of testicular germ cell tumors and compared with that of KIT (CD117) and CD30, to assess the relative utility of this marker in discriminating between seminoma and embryonal carcinoma. Forty testicular germ cell neoplasms were examined, which included 19 seminomas, three embryonal carcinomas, three teratomas, one yolk sac tumor, and 14 mixed germ cell tumors. The 14 cases of mixed germ cell tumors contained components of seminoma (n=7), embryonal carcinoma (n=11), teratoma (n=10), yolk sac tumor (n=2), and choriocarcinoma (n=1). All cases of pure seminoma and the seminomatous components of mixed germ cell tumors exhibited positive immunoreactivity for D2-40. Focal positivity for D2-40 was also observed in 29% of the embryonal carcinoma samples. D2-40 immunoreactivity in seminomas was characterized by diffuse membrane staining, whereas for embryonal carcinomas, staining was focal and distributed along the apical surfaces of the neoplastic cells. Immunohistochemical staining for KIT was observed in 92% of the seminoma samples and in none of the embryonal carcinomas. Conversely, CD30 expression was identified in 93% of the embryonal carcinoma samples and in none of the seminomas. Other germ cell components showed no immunoreactivity for D2-40, KIT, or CD30. KIT and CD30 are effective immunohistochemical markers in separating seminoma from embryonal carcinoma. Although a highly sensitive marker for seminomas, D2-40 positivity was also observed in a subset of embryonal carcinomas, thus limiting the utility of this antibody for discriminating between these two malignancies. 相似文献
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D T Baran A M Sorensen T W Honeyman R Ray M F Holick 《Journal of bone and mineral research》1990,5(5):517-524
1 alpha,25-Dihydroxyvitamin D3 rapidly increases cytosolic calcium and alters membrane phospholipid metabolism in hepatocytes. To define the causal relationship between these events, we examined the effects of 1 alpha,25-dihydroxyvitamin D3 on 32P-labeled lysophosphatidylinositol levels and cytosolic calcium as affected by pertussis toxin and 1 beta,25-dihydroxyvitamin D3, the biologically inactive analog. 32P-labeled lysophosphatidylinositol was determined by two-dimensional thin-layer chromatography. Cytosolic calcium was measured in cells loaded with quin-2AM. Within 5 min, 1 alpha,25-dihydroxyvitamin D3 increased hepatocyte cytosolic calcium by 31% (p less than 0.05) and 32P-labeled lysophosphatidylinositol by 38% (p less than 0.05). Pertussis toxin inhibited the hormone-induced rise in cytosolic calcium but not the increase in 32P-labeled lysophosphatidylinositol. Exposure to exogenous lysophosphatidylinositol for 5 min increased cytosolic calcium by 40% (p less than 0.05), an effect that was also inhibited by pertussis toxin. 1 beta,25-Dihydroxyvitamin D3 had no effect on either hepatocyte cytosolic calcium or 32P-labeled lysophosphatidylinositol but prevented the 1 alpha,25-dihydroxyvitamin D3-induced increments. The results suggest that a G protein sensitive to pertussis toxin is required for the transduction of the lysophosphatidylinositol signal but not the generation of the signal. The ability of 1 beta,25-dihydroxyvitamin D3 to inhibit the 1 alpha,25-dihydroxyvitamin D3-induced changes in phospholipids suggests that the epimer may compete with 1 alpha,25-dihydroxyvitamin D3 for an initiating receptor. 相似文献
36.
Solid and suspension grafts of fetal central nervous system (CNS) tissue rapidly reform an intact blood-brain barrier (BBB), whereas solid grafts of peripheral nervous system (PNS) tissue fail to establish a BBB as detected by horseradish peroxide (HRP) leakage, administrated intravenously. We examined the acute changes in the BBB after grafting of fetal CNS tissue in solid and suspension form and superior cervical ganglion (SCG) and PNS tissue in the same manner. Adult rats (n = 20) received fetal (day 14–15) forebrain grafts (either solid or cell suspension) to their rostral corpus callosum bilaterally. A second group (n = 20) received SCG solid and cell suspension grafts at the same coordinates with the same technique. The animals were killed on first, third, seventh, and tenth days after grafting. Intravenous HRP (Sigma, type VI, 75 mg/5-g rat) was given 1 hour before perfusion with mixed aldehydes. Fifty-micron coronal sections were examined for the presence and location of the graft by cresyl violet and AChE staining and Mesulam's TMB method to detect HRP leakage. HRP leakage was detected in the parenchyma in all groups on the first and the third days post-transplantation indicating a disrupted BBB. No HRP reaction was seen at days 7 and 10 in groups receiving fetal forebrain tissue whether solid or cell suspension. Solid grafts of SCG consistently demonstrated HRP leakage from the first through the tenth day. However, cell suspension of SCG established a BBB by 7 days. These results suggest that within the solid grafts of CNS and PNS tissue, the permeability of the vessels is dictated by the transplanted tissue itself. When cell suspensions of the same tissue are introduced, host CNS tissue dominates as the local environment resulting in non-leaky vasculature within the graft. 相似文献
37.
More and more consumers are using the Internet to find answers to questions about healthcare. Unfortunately, information at health Web sites may be incorrect, biased, and outdated. The purpose of our project was to identify Web sites on sepsis that could be used for patient and family education. We evaluated 30 sites on the basis of the Health on the Net criteria for medical and health Web sites, key content areas that patients and families should know in relation to sepsis, and readability. This article shares the process we used to evaluate the Web sites and identify the top sites for patient education. 相似文献
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Vendeville B.; Baran D.; Gascon-Barre M.; Rubin E.; Luu T.; Vallieres S. 《Nephrology, dialysis, transplantation》1995,10(11):2020-2026
BACKGROUND.: Mercuric chloride (HgCl2 induces a lymphoproliferative disorderand autoimmune glomerulonephritis in Brown Norway (BN) rats.This syndrome is the consequence of T cell-dependent polyclonalB cell activation and autoantibody production. We have previouslyshown that HgCl2-induced autoimmune perturbations can be preventedin BN rats by the administration of cyclosporin A (CsA). Themost potent vitamin D3 metabolite 1,25(OH)2 D3 (Vit D3) sharescertain immunomodulatory properties with CsA. We therefore choseto compare the effects of Vit D3 to those of CsA in BN ratstreated with HgCl2 in order to establish whether Vit D3 eitheralone or in combination with CsA can attenuate an autoimmunesyndrome in vivo. METHODS.: BN rats were treated with HgCl2 according to a standard protocol.Subgroups of rats were also given CsA alone, Vit D3 or syntheticanalogues of Vit D3 alone, or combinations of both agents. Differentdoses and routes of administration were compared. The followingmarkers of disease activity were evaluated: mortality, peakproteinuria, serum IgE concentrations, and renal immunoglobulindeposition. RESULTS.: Disease activity was markedly attenuated in all rats treatedwith CsA alone. Vit D3 and certain of its synthetic analoguesadministered alone also tempered the autoimmune process, butto a lesser extent than did CsA. The effect of CsA alone wasso potent, that no additive or synergistic effects could bedemonstrated when CsA was administered in combination with VitD3. CONCLUSIONS.: Despite similar described immunomodulatory effects in vitro,CsA is clearly more effective than Vit D3 in preventing HgCl2autoimmune disease in BN rats. This suggests that there is adifference in the cellular targets of these two agents in vivo,and/or a difference in the potency with which HgCl2-triggeredimmune activation is suppressed. 相似文献