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61.
Fortunel NO Otu HH Ng HH Chen J Mu X Chevassut T Li X Joseph M Bailey C Hatzfeld JA Hatzfeld A Usta F Vega VB Long PM Libermann TA Lim B 《Science (New York, N.Y.)》2003,302(5644):393; author reply 393
62.
Lin EK Soles CL Goldfarb DL Trinque BC Burns SD Jones RL Lenhart JL Angelopoulos M Willson CG Satija SK Wu WL 《Science (New York, N.Y.)》2002,297(5580):372-375
The continuing drive by the semiconductor industry to fabricate smaller structures using photolithography will soon require dimensional control at length scales comparable to the size of the polymeric molecules in the materials used to pattern them. The current technology, chemically amplified photoresists, uses a complex reaction-diffusion process to delineate patterned areas with high spatial resolution. However, nanometer-level control of this critical process is limited by the lack of direct measurements of the reaction front. We demonstrate the use of x-ray and neutron reflectometry as a general method to measure the spatial evolution of the reaction-diffusion process with nanometer resolution. Measuring compositional profiles, provided by deuterium-labeled reactant groups for neutron scattering contrast, we show that the reaction front within the material is broad rather than sharply defined and the compositional profile is altered during development. Measuring the density profile, we directly correlate the developed film structure with that of the reaction front. 相似文献
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Cakir-Kiefer C Le Roux Y Balandras F Trabalon M Dary A Laurent F Gaillard JL Miclo L 《Journal of agricultural and food chemistry》2011,59(9):4464-4472
α-Casozepine is a peptide, corresponding to the sequence 91-100 of the bovine α(s1)-casein, displaying anxiolytic activity in the rat. The α(s1)-casein tryptic hydrolysate containing this peptide decreases stress effects after oral administration in various species including man. Therefore, the stability of this peptide toward gastric and pancreatic proteases has been assessed by using pepsin, chymotrypsin/trypsin, Corolase PP, pepsin followed by chymotrypsin/trypsin or pepsin followed by Corolase PP. α-Casozepine was slowly degraded by chymotrypsin, much more sensitive to pepsin and Corolase PP but not completely destroyed after 4 h kinetics. The bonds in the region 91 to 95 of the α-casozepine were totally resistant to hydrolysis by all studied proteases. Surprisingly, a fragment, corresponding to the sequence 91-97 and found in all the hydrolysis media in significant amount, possessed an anxiolytic activity in three behavioral tests measuring this parameter. This peptide could participate in the in vivo activity of α-casozepine. 相似文献
65.
Bourin M Gautron J Berges M Attucci S Le Blay G Labas V Nys Y Rehault-Godbert S 《Journal of agricultural and food chemistry》2011,59(23):12368-12374
Chicken egg ovoinhibitor is a multidomain Kazal-type serine protease inhibitor with unknown function. Comparison of expression between different tissues indicated that ovoinhibitor is highly expressed in the magnum and liver followed by the uterus, which secrete egg white, egg yolk, and eggshell precursors, respectively. The results also revealed that ovoinhibitor expression is increased in the liver during sexual maturation followed by a subsequent decrease in mature hens. Ovoinhibitor was purified from the egg yolk plasma from nonfertilized eggs using two consecutive affinity chromatographies and gel filtration. Purified egg yolk ovoinhibitor was shown to inhibit trypsin and subtilisin. It was shown that purified egg yolk ovoinhibitor exhibited antimicrobial activities against Bacillus thuringiensis . The results suggest that this anti-protease plays a significant role in antibacterial egg defense against Bacillus spp., preventing contamination of table eggs (nonfertilized eggs) and protecting the chick embryo (fertilized eggs). 相似文献
66.
K. Marie McIntyre Victor J. Del Rio Vilas Simon Gubbins 《Veterinary journal (London, England : 1997)》2011,187(2):207-211
Several surveillance techniques have been used to quantify the prevalence of both classical and atypical scrapie in British sheep, namely the recording of clinical suspects (RC) and the testing of animals slaughtered at abattoir (AS) or reported as fallen stock (FS). Any estimate of prevalence based on a particular source is likely to have been affected by demographic differences in the populations sampled. In this study, the demographic characteristics of scrapie-affected holdings detected by each of the surveillance streams (RC, AS, FS) in Great Britain were compared. Analyses of all three streams indicated that the probability of an affected holding being detected by a particular stream differed by geographical area, the number of animals brought onto the holding, the type of scrapie identified (classical vs. atypical) and the year. More detailed analysis of AS and FS suggested that the annual and regional differences between these surveys could be explained by differences in sampling effort. 相似文献
67.
Adesola Odunayo DVM MS DACVECC Marie E. Kerl DVM MPH DACVIM DACVECC 《Journal of Veterinary Emergency and Critical Care》2011,21(3):236-241
Objective – To determine the difference between colloid osmotic pressure (COP) values determined from plasma versus those determined from whole blood. Design – Prospective observational study. Settings – University veterinary teaching hospital. Animals – Fifty‐three healthy dogs. Interventions – None. Measurements and Main Results – Whole blood and plasma COP, CBC, plasma biochemistry. In all dogs, plasma COP values were significantly lower (P=0.02) than whole blood COP, with a mean of difference of 0.5 mm Hg. The mean and median whole blood COP was 21.75 and 21.4 mm Hg, respectively, with a range of 17.9–27.1 mm Hg. The mean and median plasma COP was 21.2 and 20.9 mm Hg with a range of 16.7–28.9 mm Hg. Conclusions – While significant difference exists between plasma and whole blood COP, the individual values are within expected reference intervals for dogs (21–25 mm Hg). Using either sample appears to provide the same information in clinically healthy dog; however, it is recommended that clinicians utilize the same sample type for comparison in an individual patient. 相似文献
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A 24-yr-old, male western lowland gorilla (Gorilla gorilla gorilla) was diagnosed with congestive heart failure using transesophageal and transthoracic echocardiology. New York Heart Association (NYHA) Class III was assigned to the severity of the condition. Over 16 mo, this progressed to NYHA Class IV despite increasing medical therapy. Repeated evaluations suggested that implantation of a cardiac resynchronization therapy device with a defibrillator (CRT-D) could benefit this animal based on clinical signs and underlying evidence of dyssynchrony and suspected fibrotic myocardial disease. Surgical implantation of leads into the right atrium, right ventricle, and left ventricle was accomplished. The CRT-D device was placed under the thoracic pectoral muscles during an initial surgical procedure. Improvement in the gorilla's clinical condition after implantation of the CRT-D device was immediate and dramatic. Subsequent scanning of the device was accomplished through operant conditioning. The data from these device interrogations included stored and real-time cardiac data, which were used to minimize recognized environmental stressors and change device settings. Over 4 yr, case management was critical to successful device use in treatment of the clinical disease. This involved medications, training for device interrogation, exercise to increase activity and improve body condition, and phlebotomy attempts. Dietary management was necessary to manipulate caloric and sodium intake and encourage medication compliance. Cardiac resynchronization therapy device implantation, although requiring specialized equipment and surgical skill, appears to be a viable option for treatment of fibrosing cardiomyopathy with systolic dysfunction in gorillas refractory to medical management. In addition to treatment, this device provides cardiovascular data at rest that could allow for early diagnosis and treatment of gorillas with this and other cardiac conditions in the future. This describes the comprehensive medical, husbandry, and training techniques necessary to successfully manage this intense clinical case in conjunction with intracardiac device therapy. 相似文献