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Pai-shan PA Digital Content Design Graduate School of Toy Game Design National Taipei University of Education Taipei City China 《中国有色金属学会会刊》2011,(Z1)
Color filters are produced using semiconductor production techniques although problems with low yield remain to be addressed. This study presents a new means of selective removal using excimer irradiation, chemical etching, or electrochemical machining on the fifth generation TFT LCDs. The selective removal of microstructure layers from the color filter surface of an optoelectronic flat panel display, as well as complete removal of the ITO thin-films, RGB layer, or resin black matrix (BM) layer from the sub... 相似文献
3.
OBJECTIVE: Cholelithiasis is a common problem in hospitals of the Peruvian Andes; however, its prevalence in Andean communities is unknown. To estimate the prevalence of gallstone disease in this locale, we conducted a cross-sectional community study in three high-altitude Peruvian rural villages (i.e., > 3000 m above sea level). METHODS: We examined 911 volunteers > 15 yr of age from three villages for gallstone disease by history and ultrasonography. Risk factors for gallstone disease were examined in 382 volunteers from one village. RESULTS: The age-adjusted prevalence of gallstone disease ranged from 4-10% in men and from 18-20% in women. Women had significantly higher age-adjusted prevalence rates than did men. The prevalence of gallstone disease increased significantly with age and decreased significantly with alcohol consumption. Although not statistically significant, we found a positive association between gallstone disease and body mass index. CONCLUSION: The results of this study indicate that gallstone disease, commonly perceived as a disease of the developed world, is also a common problem in high-altitude Peruvian communities. 相似文献
4.
PA Bretscher 《Canadian Metallurgical Quarterly》1999,96(1):185-190
I present here a new model for the primary activation of precursor helper T cells. Observations demonstrate that the immune system learns not to respond to extrathymic, organ-specific self-antigens because of their early appearance in development. The immune system thus discriminates between peripheral self-antigens and foreign antigens and, when mature, usually makes an immune response against only the latter. Contemporary models for the activation and inactivation of T helper (Th) function do not account for such discrimination. The model proposed here is consistent with contemporary findings and incorporates a mechanism of peripheral self-nonself discrimination. 相似文献
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JM Larner H Lee RD Little PA Dijkwel CL Schildkraut JL Hamlin 《Canadian Metallurgical Quarterly》1999,27(3):803-809
An asynchronous culture of mammalian cells responds acutely to ionizing radiation by inhibiting the overall rate of DNA replication by approximately 50% for a period of several hours, presumably to allow time to repair DNA damage. At low and moderate doses, this S phase damage-sensing (SDS) pathway appears to function primarily at the level of individual origins of replication, with only a modest inhibition of chain elongation per se. We have shown previously that the majority of the inhibition observed in an asynchronous culture can be accounted for by late G1cells that were within 2-3 h of entering the S period at the time of irradiation and which then fail to do so. A much smaller effect was observed on the overall rate of replication in cells that had already entered the S phase. This raised the question whether origins of replication that are activated within S phase per se are inhibited in response to ionizing radiation. Here we have used a two-dimensional gel replicon mapping strategy to show that cells with an intact SDS pathway completely down-regulate initiation in both early- and late-firing rDNA origins in human cells. We also show that initiation in mid- or late-firing rDNA origins is not inhibited in cells from patients with ataxia telangiectasia, confirming the suggestion that these individuals lack the SDS pathway. 相似文献
7.
PA Stevenson 《Canadian Metallurgical Quarterly》1999,404(1):86-96
The validity of whiplash syndrome has been a source of debate in the medical literature for many years. Some authors have published articles suggesting that whiplash injuries are impossible at certain collision speeds; others have stated that the problem is psychological, or is feigned as a means to obtain secondary financial gain. These articles contradict the majority of the literature, which shows that whiplash injuries and their sequelae are a highly prevalent problem that affects a significant proportion of the population. The authors of the current literature critique reviewed the biomedical and engineering literature relating to whiplash syndrome, searching for articles that refuted the validity of whiplash injuries. Twenty articles containing nine distinct statements refuting the validity of whiplash syndrome were found that fit the inclusion criteria. The methodology described in these articles was evaluated critically to determine if the authors' observations regarding the validity of whiplash syndrome were scientifically sound. The authors of the current critique found that all of the articles contained significant methodologic flaws with regard to their respective authors' statements refuting the validity of whiplash syndrome. The most frequently found flaws were inadequate study size, nonrepresentative study sample, nonrepresentative crash conditions (for crash tests), and inappropriate study design. As a result of the current literature review, it was determined that there is no epidemiologic or scientific basis in the literature for the following statements: whiplash injuries do not lead to chronic pain, rear impact collisions that do not result in vehicle damage are unlikely to cause injury, and whiplash trauma is biomechanically comparable with common movements of daily living. 相似文献
8.
K Ramanathan TH Michael GJ Jiang H Hiel PA Fuchs 《Canadian Metallurgical Quarterly》1999,283(5399):215-217
Cochlear frequency selectivity in lower vertebrates arises in part from electrical tuning intrinsic to the sensory hair cells. The resonant frequency is determined largely by the gating kinetics of calcium-activated potassium (BK) channels encoded by the slo gene. Alternative splicing of slo from chick cochlea generated kinetically distinct BK channels. Combination with accessory beta subunits slowed the gating kinetics of alpha splice variants but preserved relative differences between them. In situ hybridization showed that the beta subunit is preferentially expressed by low-frequency (apical) hair cells in the avian cochlea. Interaction of beta with alpha splice variants could provide the kinetic range needed for electrical tuning of cochlear hair cells. 相似文献
9.
Acute appendicitis caused by Ascaris lumbricoides is an uncommon variant of a common disease. We describe a case in which sonography was used for preoperative diagnosis of ascaris appendicitis. 相似文献
10.
Jacomijn Pluimers Carolien Kroeze Evert Jan Bakker Hugo Challa Leen Hordijk 《Nutrient Cycling in Agroecosystems》2001,60(1-3):209-218
In this paper, present-day emissions of greenhouse gases and acidifying compounds from agriculture are analysed at the farm
level. Quantitative estimates are given for these emissions from three nested systems in the Netherlands: the agricultural
sector, greenhouse horticulture, and tomato cultivation under glass. Total emissions are subdivided into emissions from biogenic
sources and abiogenic sources. We conclude that, although most of the emissions from the agricultural sector have biogenic
sources, those from abiogenic sources should not be neglected. Abiogenic emissions are mainly from greenhouse horticulture.
The cost-effectiveness of options to reduce carbon dioxide (CO2) and nitrogen oxides (NOx) emissions from on-farm combustion of natural gas in tomato cultivation under glass is analysed. An inventory is given of
technical reduction options that are presently available in practice. Based on information about the costs and the reduction
potential of each option, cost-efficiency curves are derived for both types of emissions. Relative to a situation where none
of the described options were applied (early nineties), CO2 and NOx emissions from tomato cultivation can be reduced at most by about 70% and 75%, respectively, by combinations of technical
options.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献