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11.
Comparability of two tests of olfactory functioning 总被引:2,自引:1,他引:1
In the first of two comparisons, 50 patients who came to theConnecticut Chemosensory Clinical Research Center (CCCRC) withvarious chemosensory complaints were evaluated by a dual threshold/odoridentification test administered in the CCCRC and by the self-administeredUniversity of Pennsylvania Smell Identification Test (UPSIT).Agreement between tests proved high, with a correlation coefficientof 0.92. The UPSIT correlated better with the odor identificationcomponent than with the threshold component of the CCCRC test.This disparity stemmed largely from limitations in the reliabilityof the threshold component. An increase in the stringency ofthe criterion for determination of threshold increased the reliabilityof this component and, in a second comparison with a total of58 patients and controls, the correlation between the UPSITand CCCRC test increased. With the more stringent criterion,the correlation equalled 0.96.
2Present address: International Flavors and Fragrances, Researchand Development, Union Beach, NJ 07735, USA 相似文献
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J C Rutledge K T Cain J Kyle C V Cornett N L Cacheiro K Witt M D Shelby W M Generoso 《Mutation research》1990,229(2):161-172
N,N'-Methylenebisacrylamide (MBA), a dimer of the monomeric acrylamide, was studied for induction of clastogenic effects in germ cells of male mice. It was found to be effective in inducing dominant-lethal mutations and heritable translocations in maturing sperm. The semisterile translocation carriers and their normal counterparts were used to determine the health impact of transmitted chromosomal rearrangements through anatomical analysis of their immediate descendants in utero. As expected, semisterility resulted primarily from embryonic death during the periimplantation stages presumably caused by sperm segregants with unbalanced chromosome complement fertilizing some of the eggs. Among conceptuses that survived to mid- and late-gestation stages, there was an increased incidence of developmental anomalies including fetal death and phenotypic defects. These anomalies are assumed to be caused by certain types of unbalanced segregants that are compatible with survival beyond the periimplantation period. This class of unbalanced segregants represent in humans a major health problem to the mother and her conceptus. 相似文献
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Switch and Bait: Probing the Discriminative Basis of Odor Identification via Recognition Memory 总被引:7,自引:7,他引:0
When people misidentify everyday odors, as they often do, theirerrors may conceivably lie in faulty perceptions or in faultyaccess to the names. Discussions of the matter usually focuson the latter, as if people had no problems with perceptualaccuracy. (The problem of faulty access may get attention becauseits high subjective impact makes it particularly memorable,when it does occur.) However, studies have demonstrated breakdownsin ability to discriminate quality, from which it follows thatpeople will misidentify items through perceptual confusions.Furthermore, misidentifications often contain considerable informationabout the identities of items, as if people simply did not perceivethe items accurately, but perhaps fuzzily or with some perceptualbias. Recognition memory, with a 2-day interval between inspectionand test, provided a vehicle to address two questions on thistopic: (i) Would people notice that we had switched items andhad presented for recognition items that matched their misidentificationsrather than the original items inspected? (ii) Would peoplenot only fall for the false bait, but actually identify theswitched items correctly, and thereby imply that they were tunedto perceive those odors? People commonly failed to notice theswitches, i.e. took the bait and commonly identified the switcheditems with veridical names. Although subject to further study,the outcome suggests that when people give such names as garlicfor vinegar, orange for lime, soy sauce for molasses and manyothers, the errors often lie largely at a perceptual stage ofprocessing, i.e. at input rather than output. Chem. Senses 21:3544, 1996. 相似文献
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Summary Transformation of the spermatozoon of Ascaris suum from a spheroidal to an ameboid cell is associated with the formation of a motile pseudopodium and coalescence of the intracellular refringent granules. The pseudopodia of the ameboid spermatozoa contain filaments organized into dense patches, bundles, web-like or lace-like networks, as observed by electron microscopy.The morphology and chemistry of the refringent granules were investigated in subcellular fractions enriched for these structures. Isolated refringent granules were heterogeneous in size measuring from 0.5×0.6 to 2.3×3.5 m. Each granule is surrounded by a 110 Å thick layer. During fusion, the surfaces of the refringent granules form small extensions resembling micropodia. The process of fusion occurs at many sites on a given granule and simultanenous fusion of several granules was commonly observed.Amino acid analyses of the refringent granule proteins (RGP's) indicated: they are rich in aspartic acid or asparagine (48%), leucine (10%), serine (19%) and aromatic amino acids (11%). Gas-liquid chromatographic analyses of alditol acetate derivatives of monosaccharides released by mild acid hydrolysis showed the predominant sugars to be glucose (7.3 g/mg protein), galactose (9.2 g/mg) and N-acetylglucosamine (5.5 g/mg). Lipid analyses indicated a complex mixture of glycerides, ascarosides and waxes, together with a major component that resembled free fatty acid in mobility on TLC. 相似文献
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Asteroid bodies in multinucleate giant cells from sarcoid granulomas were investigated by immunofluorescence and electron microscopy. The following points have been established: 1. Asteroid bodies are made up of individual components of the so-called cytoskeleton, predominantly vimentin filaments. Microtubules are involved in smaller amounts in the formation of the asteroid bodies. 2. They arise within the area of the cytosphere. The body of the asteroid includes the centrioles while the arms of the asteroid usually extend into the Golgi area and occasionally up to the cell nuclei. 3. Asteroid bodies result from aggregation of the flexible filamentous and microtubular systems of the centrosphere. The processes of aggregation probably result from local fluid shifts and sol-gel transformations. 4. The stellate form of the aggregations is determined by the preexistent radial arrangement of the elements of the cytosphere. 5. The prevailing specific environment of the underlying granulomatous disease, together with the internal characteristics of the structure and function of the giant cells, in particular in states of exhaustion may play a part in their development. 相似文献
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The histological visualization of choline acetyltransferase (CAT) and acetylcholinesterase (AChE) on frozen sections of prostomia of Nereis virens indicate a concentration of cholinergic activity in the anterior brain. Components are probably sensory epithelial cells with cholinergic axons entering the brain in cephalic nerves and efferent cholinergic axons to prostomial muscle leaving the brain in the same nerves. There are also subepidermal cholinergic cells that may be second order motor neurons serving epidermal mucous cells. The smaller, second lobe of the corpora pedunculata and its associated vertical fibre tract are CAT4 and appear continuous, on each side of the cerebral ganglion, with a dorsal and a ventral longitudinal bundle of AChE+ fibers. This system tapers to nothing at the level of the posterior eyes. There is a small AChE+ component to each optic nerve and AChE is present in the nuchal epithelium. These observations are discussed in relation to earlier studies on aminergic and neurosecretory activity in the same ganglion. 相似文献
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In vivo intermembrane transfer of phospholipids in the photosynthetic bacterium Rhodopseudomonas sphaeroides. 总被引:17,自引:15,他引:2 下载免费PDF全文
The kinetics of accumulation of phospholipids into the intracytoplasmic membrane of Rhodopseudomonas sphaeroides have been examined. We have previously demonstrated that accumulation of phospholipids in the intracytoplasmic membrane is discontinuous with respect to the cell cycle. In this study we demonstrated a sevenfold increase in the rate of phospholipid incorporation into the intracytoplasmic membrane concurrent with the onset of cell division. Pulse-chase labeling studies revealed that the increase in the rate of phospholipid accumulation into the intracytoplasmic membrane results from the transfer of phospholipid from a site other than the intracytoplasmic membrane, and that the transfer of phospholipid, rather than synthesis of phospholipid, is most likely subject to cell cycle-specific regulation. The rates of synthesis of the individual phospholipid species (phosphatidylethanolamine, phosphatidyglycerol, and an unknown phospholipid) remained constant with respect to one another throughout the cell cycle. Similarly, each of these phospholipid species appeared to be transferred simultaneously to the intracytoplasmic membrane. We also present preliminary kinetic evidence which suggested that phosphatidylethanolamine may be converted to phosphatidycholine within the intracytoplasmic membrane. 相似文献