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MH West RE Barsley JE Hall S Hayne M Cimrmancic 《Canadian Metallurgical Quarterly》1992,37(6):1480-1488
This article is a discussion of the use of narrow-band light sources coupled with cameras equipped with band-pass filters to document patterned injuries on human skin. Several case reports are included. 相似文献
46.
Mineralocorticoid action is facilitated by 11 beta-hydroxysteroid dehydrogenase type II (11 beta HSD2), which metabolizes glucocorticoids and allows aldosterone to bind to the nonselective mineralocorticoid receptor. We have recently demonstrated the presence of the 11 beta HSD2 protein in a wide range of human epithelia, suggesting that it is the sole isoform endowing specificity in man. In the present study we have used an immunopurified polyclonal antibody (RAH23) raised against a C-terminal peptide derived from the cloned rat 11 beta HSD2 protein to perform immunohistochemical and molecular analysis in rat tissues. In frozen sections of rat kidney, strong staining was seen with the RAH23 antibody in the distal tubule; weaker staining was observed in the thick ascending loop of Henle and the medullary and papillary collecting ducts. Punctate cortical staining was observed in the fetus at 20 days gestation and in 8-day-old rats, with a noticeable increase in the staining pattern at 16 days of age. The kidney did not attain the adult pattern of staining until 28 days of age. Epithelia of ileum and colon also stained with RAH23, as did excretory ducts of the submandibular gland. Intrahepatic and excretory bile ducts displayed strong immunoreactivity in the epithelial lining. Rat adrenal glands showed evidence of the 11 beta HSD2 antigen in the zona fasciculata and zona reticularis, but not in the zona glomerulosa or medulla. Western blot analysis with the RAH23 antibody revealed strong bands in the kidney, colon, adrenal gland, and submandibular gland at 40 kDa, colinear with the migration of the cloned 11 beta HSD2 enzyme. A band of medium intensity was also seen at this size in the pancreas, whereas a band of moderate intensity was seen in the bile duct, and weaker bands were noticed in the stomach, small intestine, and liver, with a diffuse band at 36-42 kDa in the prostate. Strong bands were seen in the pancreas and prostate at 78 kDa, with weaker signals in the colon, adrenal, stomach, and bile duct. A number of tissues also displayed multiple bands at about 30 kDa. Enzymatic assays on tissue homogenates showed extensive conversion of corticosterone to its 11-dehydro product in an NAD-dependent manner in the submandibular gland, adrenal gland, and kidney, but not in the pancreas or prostate. This study confirms the ubiquitous presence of 11 beta HSD2 in sodium-transporting epithelia, demonstrates the high level of 11 beta HSD2 protein and enzyme activity in the rat adrenal, and suggests a possible role for the enzyme in the biliary system. Further studies are required to determine the relevance of the various molecular species to the activity, latency, and processing of the enzyme. 相似文献
47.
We have isolated a putative serine/threonine receptor kinase gene with an expression pattern indicating that it may play a role in the stylar response to pollination. Differential display PCR was used to select tobacco mRNAs with increased accumulation following pollination. NTS16, a cDNA identified by this method, is homologous to a ca. 2.4 kb mRNA primarily expressed in pistil tissues. Levels of this mRNA increase during floral development and are further increased by pollination reaching maximal accumulation 12-18 hours after pollination and then declining. mRNA levels can also be increased by the application of ethylene to unpollinated flowers. A polypeptide encoded by the NTS 16 open reading frame has sequence similarity to the catalytic domain of several receptor protein kinases from plants including the S-receptor kinases implicated in the rejection of self-pollen in Brassica species and the Pto gene product of tomato which confers resistance to a bacterial pathogen. 相似文献
48.
Laura Akers Herbert H Severson Judy A Andrews Edward Lichtenstein 《Nicotine & tobacco research》2007,9(9):907-914
This study assessed the cost-effectiveness of two low-intensity programs for quitting smokeless tobacco, based on results of a randomized trial with 1,069 volunteer participants. Cost data were collected for two levels of intervention: manual only (a self-help manual) and assisted self-help (the manual plus a videotape and two supportive phone calls from tobacco cessation counselors). Incremental cost-effectiveness ratios were calculated for assisted self-help vs. quitting on one's own, using the manual-only quit rate and data from another study as alternative proxies for no intervention. A threshold analysis was conducted to determine the spontaneous quit rate at which the manual-only intervention becomes more cost-effective than assisted self-help. The cost to provide and receive the assisted self-help intervention averaged US $56 per participant vs. $20 for the manual-only intervention (societal perspective, Year 2000 dollars). Estimates for incremental cost per quit for the assisted self-help intervention ranged from $922 to $1,758, depending on the proxy used for no intervention. The manual-only intervention was more cost-effective than assisted self-help if quitting among motivated chewers who do not receive treatment does not exceed 3.4%. Support from a wife or partner added little cost to a quit attempt for male chewers ($3-$4). Providing a manual, video, and brief phone counseling to smokeless tobacco users who want to quit is a reasonable use of health care resources. The self-help quitting guide also may be a cost-effective treatment, but it remains to be demonstrated whether it is more effective than quitting on one's own. 相似文献
49.
Self-help cessation programs for smokeless tobacco users: long-term follow-up of a randomized trial.
Hebert H Severson Judy A Andrews Edward Lichtenstein Brian G Danaher Laura Akers 《Nicotine & tobacco research》2007,9(2):281-289
This paper presents long-term outcomes of the largest clinical trial of smokeless tobacco (SLT) cessation reported to date. SLT users in five northwestern states were recruited to call a toll-free number, and 1,069 users were randomized to one of two self-help conditions: either a manual-only condition or an assisted self-help condition, which included the manual, a targeted video, and two support phone calls. Significant between-group differences were not found for either the 12- or 18-month point-prevalence measure of abstinence from either SLT only or all tobacco products using outcomes based on either the responder or intention-to-treat outcomes. However, using a repeated point-prevalence measure across all three assessment points, we found that significantly more assisted self-help participants reported abstinence, compared with manual-only participants. Compared with manual-only participants, those in the assisted self-help condition were significantly more likely to use recommended cessation techniques. Results demonstrate that low-cost, minimal interventions delivered by mail and phone can help a sizable proportion of individuals quit using SLT. 相似文献
50.
Elizabeth Andrews 《河流研究与利用》1989,4(2):199-202
The British otter Lutra lutra L. requires good water quality, an adequate supply of fish and certain types of vegetation or cavities (holts) adjacent to water bodies for resting and breeding sites. In the U.K. otters and their holts are legally protected. Trained surveyors are needed to confirm the presence of otters on a river as the animals are rarely seen, but their tracks and droppings (spraints) may be detected. To evaluate a river for otters, information is required on water quality, fish species and biomass, as well as available habitat. Pioneer evaluation work based on the River Corridor Survey techniques has been done on Welsh rivers with good otter populations. Riparian vegetation, especially trees, is shown to be particularly important. This work is now being extended to areas on the margins of otter distribution such as the lower river Wye in England and Wales. Such surveys provide important management information for water authorities and give opportunities for enhancement work to benefit this animal. 相似文献