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排序方式: 共有1030条查询结果,搜索用时 15 毫秒
91.
Sujith Vengayil M. Vanathi Anita Panda Sudharshan Khokhar 《Contact lens & anterior eye》2008,31(3):161-163
PURPOSE: To report a case of retained Descemet's membrane after penetrating keratoplasty for congenital hereditary endothelial dystrophy (CHED) documented by anterior segment optical coherence tomography and review of literature. METHODS: Case report and review of literature. RESULTS: A 14-year-old boy underwent penetrating keratoplasty for CHED. A retained host Descemet's membrane was detected with a supernumerary anterior chamber on the first postoperative day. The retained Descemet's membrane was documented using slit lamp adapted anterior segment optical coherence tomography (SLOCT). Surgical intervention for the Descemet's membrane removal was done in the third postoperative week. The complete removal of the membrane was confirmed on SLOCT. CONCLUSION: Inadvertent retention of the host Descemet's membrane is a rare but possible complication in penetrating keratoplasty for CHED. Proper anticipation, early detection and removal will help in preventing any undue risk of graft failure. 相似文献
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93.
Presents 5 paradoxes of masochism, which delineate intrapsychic and interpersonal patterns in which pain and "unpleasure" seem to become aims. Elements of the apparent contradictions inherent in masochistic disorders and some of their transference and countertransference implications are discussed. The 5 paradoxes highlight (1) intrapsychic conflict around issues of drive and defense, (2) conflict between autonomy and gratification through depending on others, (3) pain inherent in the quest for perfection, (4) pain associated with attachment to the object, and (5) pleasure evokes physical pain and injury, a screen for early dire physical trauma. Case material illustrates each paradox. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Stephens BS Kapernick A Eaglesham G Mueller J 《Environmental science & technology》2005,39(22):8891-8897
Water-sampler equilibrium partitioning coefficients and aqueous boundary layer mass transfer coefficients for atrazine, diuron, hexazionone and fluometuron onto C18 and SDB-RPS Empore disk-based aquatic passive samplers have been determined experimentally under a laminar flow regime (Re = 5400). The method involved accelerating the time to equilibrium of the samplers by exposing them to three water concentrations, decreasing stepwise to 50% and then 25% of the original concentration. Assuming first-order Fickian kinetics across a rate-limiting aqueous boundary layer, both parameters are determined computationally by unconstrained nonlinear optimization. In addition, a method of estimation of mass transfer coefficients--therefore sampling rates--using the dimension-less Sherwood correlation developed for laminar flow over a flat plate is applied. For each of the herbicides, this correlation is validated to within 40% of the experimental data.The study demonstrates that for trace concentrations (sub 0.1 microg/L) and these flow conditions, a naked Empore disk performs well as an integrative sampler over short deployments (up to 7 days) for the range of polar herbicides investigated. The SDB-RPS disk allows a longer integrative period than the C18 disk due to its higher sorbent mass and/or its more polar sorbent chemistry. This work also suggests that for certain passive sampler designs, empirical estimation of sampling rates may be possible using correlations that have been available in the chemical engineering literature for some time. 相似文献
95.
Anita R Jindal Alistair S Grandison Geoffrey Campbell-Platt 《Journal of the science of food and agriculture》1993,61(4):449-456
Chhana whey contains less protein than Cheddar cheese whey, acid casein and cottage cheese whey, and the protein composition is quite different. Electrophoretic methods demonstrated that most of the proteins in chhana whey were denatured, and there was considerable variation in the protein composition between samples of chhana whey and paneer whey obtained from different sources. The effect of storage temperature and time (up to 10 h at 40°C, 50°C, 60°C, 70°C and 80°C) on the quality of chhana whey was investigated. There were no significant changes in the pH and titratable acidity in any of these cases. Electrophoretic separation showed no qualitative changes in the protein composition pattern of chhana whey after up to 10 h of storage at 70°C. 相似文献
96.
The present study deals with an unsteady magnetohydrodynamic natural convective flow of a viscous, incompressible fluid past an exponentially accelerated porous plate surrounded by a porous medium with suction or injection. The novelty of the current research is to analyze the behavior of the flow due to mass transfer with first-order chemical reaction in the presence of a heat source in the energy equation. The existence of suction/injection and radiation parameters in the flow enhances the utility of the research as they are an integral part of nuclear reactors, thermal and chemical engineering processes, and many more. The Laplace transform technique (via Bromwich contour) is applied to solve exactly the governing equations. The nature of the flow velocity, temperature, and concentration profiles due to the impact of pertinent flow parameters are presented graphically. The numerical outcomes of coefficient of skin friction, rate of heat transfer, and mass transfer are obtained in tabular form. The results indicate that the skin friction increases slowly with the reaction parameter and largely with the suction parameter, whereas the concentration gradient increases at a much higher rate with the reaction parameter. The fluid injection has a negative impact on the velocity gradient. It is seen that the heat source enhances both velocity and temperature profiles throughout the flow field, whereas the first-order chemical reaction acts reversely on the velocity and mass transfer process. The current research can be applied to identify the cause behind the drag force produced in seepage flow due to the heated or cooled accelerated plate. 相似文献
97.
A functional hydrogen producing consortium was isolated from soil by heat pre-treatment technique and hydrogen production at different substrate concentration was evaluated. The forest soil was heat pre-treated at 65, 80, 95, 105 and 120 °C temperature for 1 h. As revealed by PCR-DGGE analysis and hydrogen yield, the hydrogen producing microbial community changed with increase in heat pre-treatment temperatures giving potential hydrogen producing consortium at 95–105 °C soil pre-treatment. The maximum hydrogen production rate, hydrogen yield and cumulative hydrogen with 15–20 g glucose were 1390–1576 mL/L/day, 1.83–1.93 mol H2/mol glucose, and 2966–3146 mL H2/L, respectively. The metabolic pathways shifted from ethanol-type to acetate–formate type as soil pre-treatment temperature increased from 65 to 120 °C. The soil heat pre-treatment approach is effective for isolating hydrogen producing natural Clostridium consortium from the soil as enumerations of the functional strains need specific temperature range to florish. 相似文献
98.
Microsystem Technologies - The technique of hiding knowledge in certain details is steganography. One of the main trends of computer infrastructure and connectivity following the advent of the... 相似文献
99.
Wireless Personal Communications - Wireless sensor network is gaining popularity due to its large-scale deployment in Internet of Things. The constraints of resources influence the protocol design... 相似文献
100.
Heikkilä Päivi Honka Anita Kaasinen Eija Väänänen Kaisa 《Cognition, Technology & Work》2021,23(4):831-846
Cognition, Technology & Work - The work on the factory floor is gradually changing to resemble knowledge work due to highly automated manufacturing machines. In the increasingly automated work... 相似文献