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951.
952.
The anti-CD1 monoclonal antibodies IAH-CC14 and SBU-T6 were used to immunopurify CD1 antigens from sheep thymocytes. The
amino-terminal sequence of IAH-CC14 yielded 13 amino acids, and 29 amino acids were obtained from the SBU-T6 antigen. The
sequence of the IAH-CC14 antigen was 100% identical to the predicted sequence of the sheep CD1B clone, SCD1B-42. The 29 amino acid sequence of the SBU-T6 antigen did not match identically with the derived amino acid sequence of any of
the previously reported sheep CD1 genes but had closest similarity to the derived sequence of human CD1E. Degenerate polymerase chain reaction primers based on this sequence identified a group 2 sheep CD1 gene. The predicted amino acid sequence of this gene shows that it is not identical to the SBU-T6 peptide, indicating that
a different, CD1D-like gene was cloned.
Received: 22 June 1998 / Revised: 16 September 1998 相似文献
953.
954.
Marna Rayl Greenberg Elizabeth C. Moore Michael C. Nguyen Brian Stello Arnold Goldberg Robert D. Barraco Bernadette G. Porter Anita Kurt Stephen W. Dusza Bryan G. Kane 《The Yale journal of biology and medicine》2016,89(2):261-267
The CDC reports that among older adults, falls are the leading cause of injury-related death and rates of fall-related fractures among older women are twice those of men. We set out to 1) determine patient perceptions (analyzed by gender) about their perceived fall risk compared to their actual risk for functional decline and death and 2) to report their comfort level in discussing their fall history or a home safety plan with their provider. Elders who presented to the Emergency Department (ED†) were surveyed. The survey included demographics, the Falls Efficacy Scale (FES) and the Vulnerable Elders Survey (VES); both validated surveys measuring fall concern and functional decline. Females had higher FES scores (mean 12.3, SD 5.9) than males (mean 9.7, SD 5.9 p = .007) in the 146 surveys analyzed. Females were more likely to report an increased fear of falling, and almost three times more likely to have a VES score of 3 or greater than males (OR = 2.86, 95% CI: 1.17-7.00, p = .02). A strong correlation was observed between FES and VES scores (r = 0.80, p < .001). No difference in correlation was observed between males and females, p = .26. Participants (77 percent) reported they would be comfortable discussing their fall risk with a provider; there was no difference between genders (p = .57). In this study, irrespective of gender, there appears to be a high association between subjects’ perceived fall risk and risk for functional decline and death. The majority of patients are likely willing to discuss their fall risk with their provider. These findings may suggest a meaningful opportunity for fall risk mitigation in this setting. 相似文献
955.
956.
Bernadette M. Marriott Robert W. Marriott Jean Norris Deborah Lee 《Journal of medical primatology》1993,22(6):348-354
A semi-natural habitat that was designed to house a social group of squirrel monkeys (Saimiri sciureus sciureus) at Goucher College, in Maryland is described. The design could be readily adapted for use with other small primate species. 相似文献
957.
958.
The ultrastructures of the retractor muscles of Gené's organs in the cattle ticksBoophilus microplus andAmblyomma variegatum are described. The innervation, neuromuscular junctions, and insertions of the muscles are also described. The retractor muscles are important in controlling the actions of Gené's organ, the egg waxing organ in ticks, during oviposition in the female. The ultrastructural features of the muscles are typical of arthropod muscles, and the nerve terminals at the neuromuscular junctions contain small electron lucent synaptic vesicles with a diameter of 50 nm, and also larger dense core vesicles with a diameter of 100 nm. Evidence is presented implicatingl-glutamate andl-aspartate as putative excitatory transmitters at the tick neuromuscular junction. The excitatory post-synaptic potentials recorded in the muscles were abolished in the presence of low concentrations ofl-glutamic acid andl-aspartic acid, but were unaffected by acetyl-choline, 4-aminobutyric acid and octopamine, suggesting that glutamic acid and aspartic acid interact with receptors on the muscle membrane. 相似文献
959.
The incubation of 4-chloronitrosobenzene with yeast transketolase, Mg2+, and thiamime pyrophosphate in the presence of excess xylulose-5-phosphate resulted in the formation of N-(4-chlorophenyl)glycolhydroxamic acid. This enzyme-catalyzed C2 transfer displayed a Km of 0.92 mM and a Vmax of 5.2 × 10?2 μmol min?1 unit enzyme?1. Conversion was inhibited by the normal acceptor sugar, ribose-5-phosphate, with a Ki of 0.35 mM. Kinetic analysis showed inhibition was competitive in nature, reinforcing the proposed theory for similarity in catalytic formation of both the hydroxamic acid and sedoheptulose-7-phosphate. Most interesting about the conversion of this alternative substrate is that even at high concentrations of ribose-5-phosphate, a significant amount of the nitroso compound was converted to the hydroxamic acid, implying that 4-chloronitrosobenzene can successfully compete for active glycoaldehyde. Using the yeast enzyme as a model for transketolase in higher organisms, the adventitious conversion of such xenobiotics in vivo is proposed. 相似文献
960.
Anelia Iantcheva Mireille Chabaud Viviane Cosson Marielle Barascud Bernadette Schutz Catherine Primard-Brisset Patricia Durand David G. Barker Mariana Vlahova Pascal Ratet 《Plant cell reports》2009,28(10):1563-1572
Insertion mutant collections are powerful tools for genetic studies in plants. Although large-scale insertional mutagenesis
using T-DNA is not feasible in legumes, the Tnt1 tobacco retrotransposon can be used as a very efficient mutagen in the Medicago truncatula R108 genotype. In this article, we show that Tnt1 can also be exploited to create insertional mutants via transformation and/or regeneration in the reference cultivar Jemalong.
Tnt1 insertional mutagenesis in Jemalong following Agrobacterium tumefaciens-mediated transformation was found to be very efficient, with an average of greater than 15 insertions/line. In contrast,
regeneration using low-copy transgenic starter lines resulted in a highly variable rate of new Tnt1 insertions. With the goal of increasing the number of additional Tnt1 insertions during regeneration of starter lines, we have compared the insertion frequencies for a number of different regeneration
protocols. In addition, we have been able to show that sucrose-mediated osmotic shock preceding regeneration significantly
increases the transposition frequency. Under optimal conditions, 95% of the regenerated Jemalong plants possess new insertions. 相似文献