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801.
LINDA M. McINNES IAN R. DADOUR MEREDITH E. STEWART WILLIAM G. F. DITCHAM PETER MAWSON PETER B. S. SPENCER 《Molecular ecology resources》2005,5(3):504-506
Microsatellite loci were isolated from Carnaby's black cockatoo (Calyptorhynchus latirostris: Aves), a highly valued, endangered, and endemic species of bird from Western Australia. This study describes three dinucleotide and one tetranucleotide microsatellite loci for which the primers produced clear and polymorphic amplification patterns with between two and nine alleles and moderate levels of variability. Two additional dinucleotide markers which were monomorphic in the Carnaby's cockatoo were able to amplify and were polymorphic in two other species of black cockatoo, greatly increasing the utility of these markers. 相似文献
802.
W E Wright 《BioTechniques》1992,13(5):772-779
A technique called partial-digest sequencing that permits DNA of 4-6 kb in length to be sequenced without subcloning is described. The method exploits the specific cuts introduced by partial digestion with restriction endonucleases that have 4-base recognition sites to produce ordered ladders of PCR-amplified fragments. The staggered ends contain PCR primers and can thus be individually sequenced using conventional methods to yield overlapping sequences covering the entire region. This method should have significant impact on both large and small DNA sequencing projects and find many applications in general manipulations in which ordered sets of deletions need to be produced. 相似文献
803.
Purification and characterization of a lysophospholipase from human amnionic membranes 总被引:1,自引:0,他引:1
We have identified the presence of a lysophospholipase in human placental tissues and have purified this enzyme from the amnion. The specific activity was highest in the amnion and decreased across adjacent tissues. The purification involved the use of DEAE-Sephadex, phenyl-Sepharose, hydroxylapatite, and sulfylpropyl Sephadex chromatography. The activity of the purified enzyme toward palmitoyl lysophosphatidylcholine is 2.5 mumol min-1 mg-1 and the pH optimum is 7.0. The enzyme is not inhibited by EDTA and does not appear to have a metal ion requirement. The enzyme may be of membrane origin; the purified enzyme requires the presence of detergent during storage. The effects of substrate composition and physical state on enzymatic activity were explored. The enzyme was not active toward mono-, di-, or triglycerides, nor toward diacyl phospholipid. The enzyme was active toward myristoyl and palmitoyl lysophosphatidylcholine at concentrations where these substrates spontaneously form micelles or where Triton X-100 was used to induce co-micellization of the substrate at low concentrations with detergent. A role for this enzyme in processing the lysophospholipid product of phospholipase A action must be considered in evaluating arachidonic acid production in human fetal membranes and placental tissue, particularly during the initiation of labor. 相似文献
804.
E K Lund M W Smith M A Peacock 《Comparative biochemistry and physiology. A, Comparative physiology》1986,85(1):175-181
The influence of parental spleen cells on the postnatal development of brush border microvillus membrane structure and the ability to transport lysine and alanine has been studied in the mouse jejunum during the second week of postnatal life. Control tissue taken from 7-11 day old mice has an unchanging crypt-villus structure and a low enterocyte migration rate of about 1 micron hr-1. Microvillus elongation in crypt enterocytes takes 6 days to complete under these conditions. Lysine and alanine transport begin 2 days after structural differentiation has ceased. Parental spleen cells injected into 1-2-day-old F1 mice cause crypt cell hyperplasia, villus shortening and a 3-6-fold increase in enterocyte migration rate after a period of 8 days. These effects are associated with large reductions in the time needed to complete microvillus membrane development and first express absorptive function. Lysine and alanine transport begin approximately 6 hr after structural differentiation has ceased under these conditions. Adaptive changes in the development of enterocyte structure and function, induced by injection of parental spleen cells, bear some resemblance to other changes found to occur normally at weaning and in adult animals subjected to controlled changes in diet and environmental temperature. The possibility that common principles govern enterocyte adaptation and that some of these still apply in an intestine undergoing an immune reaction is discussed. 相似文献
805.
The oscillations of the free fatty acid concentration in the serum and white (epididymal) adipose tissue, of triglycerides in the serum and liver, of total serum, liver and adrenal cholesterol and of serum phospholipids were studied at 3-hour intervals for a period of 24 hours in fed male Wistar rats and in animals fasted for 24 hours (both adapted to an illumination regimen of 12 hours' light and 12 hours' darkness. The rhythm--studied by means of the cosinor analysis--was present in most of the given parameters; it was not recorded in the liver triglycerides and serum phospholipids of fasted rats and in the adrenal cholesterol of fed animals. Apart from the circadian rhythm, many parameters distinctly displayed an ultradian rhythm, mainly an approximately 12-hour period. In general, one day's starvation did not significantly affect the course of the circadian oscillations of the given indicators of rat lipid metabolism. 相似文献
806.
T J Wallace E M Kodsi T B Langston M R Gergis W M Grogan 《The Journal of biological chemistry》2001,276(35):33165-33174
Site-directed mutagenesis is used to identify amino acid residues that dictate reported differences in substrate specificity between rat hepatic neutral cytosolic cholesteryl ester hydrolase (hncCEH) and rat lung carboxylesterase (LCE), proteins differing by only 4 residues in their primary sequences. Beginning with LCE, the substitution Met(423) --> Ile(423) alone or in combination with other mutations increased activity with p-nitrophenylcaprylate (PNPC) relative to more hydrophilic p-nitrophenylacetate (PNPA), typical of hncCEH. The substitution Thr(444) --> Met(444) was necessary but not sufficient for expression of cholesteryl esterase activity in COS-7 cells. The substitution Asn(506) --> Ser(506), creating a potential phosphorylation site, uniformly increased activity with both PNPA and PNPC, was necessary but not sufficient for expression of cholesteryl esterase activity and conferred susceptibility to activation by cAMP-dependent protein kinase, a property of hncCEH. The 3 mutations in combination were necessary and sufficient for expression of cholesteryl esterase activity by the mutated LCE. The substitution Gln(186) --> Arg(186) selectively reduced esterase activity with PNPA and PNPC but was not required for cholesteryl esterase activity. Homology modeling from x-ray structures of acetylcholinesterases is used to propose three-dimensional models for hncCEH and LCE that provide insight into the effects of these mutations on substrate specificity. 相似文献
807.
E V Diatlovitskaia E V Fomina-Ageeva L D Bergel'son 《Biokhimii?a (Moscow, Russia)》1985,50(8):1290-1294
Neutral glycosphingolipids of murine T-lymphoma EL-4 were studied. The major glycolipid components were identified as GlcCer, LacCer, GgOse3Cer and GgOse4Cer. It has been shown for the first time that not only gangliosides but also neutral glycolipids are shed from the cell surface into the outer medium. 相似文献
808.
E Grundy 《BMJ (Clinical research ed.)》1984,288(6418):663-664
809.
Rachel J. Primrose Toral Zaveri Alyssa J. Bakke Gregory R. Ziegler Howard R. Moskowitz John E. Hayes 《PloS one》2016,11(3)
Vaginal microbicides potentially empower women to protect themselves from HIV and other sexually transmitted infections (STIs), especially when culture, religion, or social status may prevent them from negotiating condom use. The open literature contains minimal information on factors that drive user acceptability of women’s health products or vaginal drug delivery systems. By understanding what women find to be most important with regard to sensory properties and product functionality, developers can iteratively formulate a more desirable product. Conjoint analysis is a technique widely used in market research to determine what combination of elements influence a consumer’s willingness to try or use a product. We applied conjoint analysis here to better understand what sexually-active woman want in a microbicide, toward our goal of formulating a product that is highly acceptable to women. Both sensory and non-sensory attributes were tested, including shape, color, wait time, partner awareness, messiness/leakage, duration of protection, and functionality. Heterosexually active women between 18 and 35 years of age in the United States (n = 302) completed an anonymous online conjoint survey using IdeaMap software. Attributes (product elements) were systematically presented in various combinations; women rated these combinations of a 9-point willingness-to-try scale. By coupling systematic combinations and regression modeling, we can estimate the unique appeal of each element. In this population, a multifunctional product (i.e., broad spectrum STI protection, coupled with conception) is far more desirable than a microbicide targeted solely for HIV protection; we also found partner awareness and leakage are potentially strong barriers to use. 相似文献
810.
Two patients who presented initially with breast masses proven to be plasmacytomas, are described. In both cases the breast masses led to the diagnosis of multiple myeloma, which was retrospectively already present at the time of the breast biopsy. One patient with IgG lambda-type myeloma developed plasma cell leukemia and amyloidosis and failed to respond to radiochemotherapy. The second patient was in complete remission, four years after therapy, but has subsequently relapsed and died. All cases of breast plasmacytoma, described in the medical literatures are reviewed, and guidelines for future therapy are suggested. 相似文献