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1.
Phys Rev Lett ; 120(15): 151301, 2018 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-29756850

RESUMEN

This Letter reports the results from a haloscope search for dark matter axions with masses between 2.66 and 2.81 µeV. The search excludes the range of axion-photon couplings predicted by plausible models of the invisible axion. This unprecedented sensitivity is achieved by operating a large-volume haloscope at subkelvin temperatures, thereby reducing thermal noise as well as the excess noise from the ultralow-noise superconducting quantum interference device amplifier used for the signal power readout. Ongoing searches will provide nearly definitive tests of the invisible axion model over a wide range of axion masses.

2.
Phys Rev Lett ; 121(26): 261302, 2018 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-30636160

RESUMEN

The µeV axion is a well-motivated extension to the standard model. The Axion Dark Matter eXperiment (ADMX) collaboration seeks to discover this particle by looking for the resonant conversion of dark-matter axions to microwave photons in a strong magnetic field. In this Letter, we report results from a pathfinder experiment, the ADMX "Sidecar," which is designed to pave the way for future, higher mass, searches. This testbed experiment lives inside of and operates in tandem with the main ADMX experiment. The Sidecar experiment excludes masses in three widely spaced frequency ranges (4202-4249, 5086-5799, and 7173-7203 MHz). In addition, Sidecar demonstrates the successful use of a piezoelectric actuator for cavity tuning. Finally, this publication is the first to report data measured using both the TM_{010} and TM_{020} modes.

3.
Artículo en Inglés | MEDLINE | ID: mdl-31092963

RESUMEN

Backscatter of electrons from a beta spectrometer, with incomplete energy deposition, can lead to undesirable effects in many types of experiments. We present and discuss the design and operation of a backscatter-suppressed beta spectrometer that was developed as part of a program to measure the electronantineutrino correlation coefficient in neutron beta decay (aCORN). An array of backscatter veto detectors surrounds a plastic scintillator beta energy detector. The spectrometer contains an axial magnetic field gradient, so electrons are efficiently admitted but have a low probability for escaping back through the entrance after backscattering. The design, construction, calibration, and performance of the spectrometer are discussed.

4.
Rev Sci Instrum ; 88(8): 083503, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28863637

RESUMEN

We describe an apparatus used to measure the electron-antineutrino angular correlation coefficient in free neutron decay. The apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight asymmetry that is counted directly, avoiding the need for proton spectroscopy. Details of the method, apparatus, detectors, data acquisition, and data reduction scheme are presented, along with a discussion of the important systematic effects.

5.
Toxicol In Vitro ; 19(3): 365-71, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15713543

RESUMEN

The objective of this study was to quantify the ability of sublethal concentrations of several gold compounds to differentially modulate the monocytic secretion of key cytokines that are important in the etiology of rheumatic diseases. Human THP1 monocytic cells were exposed to the anti-rheumatic drugs auranofin (AF), gold sodium thiomalate (GSTM) or HAuCl4 (Au(III)) for 24-72 h. Succinate dehydrogenase (SDH) activity of the monocytes was used to determine sublethal concentrations. Monocytes were then exposed to sublethal concentrations of gold compounds for 72 h, and the activator lipopolysaccharide (LPS) was added (or not) to cultures for the last 6h. The secretion of IL6, IL8, IL10, and TNFalpha were measured in cell supernatants using ELISA. Cytokine secretion was compared among concentrations and gold compounds. SDH experiments established a sublethal concentration range of 0-75 microM for GSTM and Au(III) and 0-0.5 microM for AF. In cytokine experiments, none of the compounds alone activated secretion of any of the cytokines, but all differentially (50-440%, p<0.05) increased LPS-induced secretion of IL6 and IL8 over TNFalpha and IL10. In conclusion, sublethal concentrations of AF, GSTM, and Au(III) all may differentially modulate activation of monocytic cells, and this differential modulation may be important in the mechanisms of action of these compounds.


Asunto(s)
Antirreumáticos/toxicidad , Auranofina/toxicidad , Cloruros/toxicidad , Citocinas/metabolismo , Compuestos de Oro/toxicidad , Tiomalato Sódico de Oro/toxicidad , Monocitos/efectos de los fármacos , Línea Celular , Relación Dosis-Respuesta a Droga , Humanos , Monocitos/metabolismo , Succinato Deshidrogenasa/metabolismo
6.
Rev Sci Instrum ; 86(12): 123305, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26724020

RESUMEN

In an effort to extend the usefulness of microwave cavity detectors to higher axion masses, above ∼8 µeV (∼2 GHz), a numerical trade study of cavities was conducted to investigate the merit of using variable periodic post arrays and regulating vane designs for higher-frequency searches. The results show that both designs could be used to develop resonant cavities for high-mass axion searches. Multiple configurations of both methods obtained the scanning sensitivity equivalent to approximately 4 coherently coupled cavities with a single tuning rod.

7.
J Invest Dermatol ; 65(2): 220-2, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1151113

RESUMEN

The proteins obtained from separated cells of neonatal rat dermis, four cell populations of epidermis, and an epidermal nuclear preparation were analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Comparison of the results of the insoluble proteins of the dermis and epidermis show no similarity of the major protein bands, indicating the effective separation of the dermis and epidermis and absence of cross-contamination. The gels of the soluble proteins of the basal, spinous, and granular layers of the epidermid are very similar. Only the pattern of bands of the cornified cells differs in that some of these bands are absent and at least three new bands are present. The insoluble proteins have specific differences in the protein content related to the cell structure. An example is the nuclear protein bands which correspond with the most prominent bands in the gels of basal and spinous layer proteins, but are absent, with the possible exception of one band, from gels of cornified cell proteins.


Asunto(s)
Electroforesis en Gel de Poliacrilamida , Proteínas/análisis , Piel/análisis , Animales , Animales Recién Nacidos , Núcleo Celular/análisis , Separación Celular , Proteínas/aislamiento & purificación , Ratas , Dodecil Sulfato de Sodio
8.
J Invest Dermatol ; 65(2): 223-7, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-50389

RESUMEN

Keratohyalin extracts from newborn rat epidermis were prepared by potassium phosphate and citric acid-detergent extraction procedures. These preparations were compared by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and amino acid analysis. The major band of the potassium phosphate extract has a molecular weight of 48,000. The major bands of the citric acid-detergent preparation have molecular weights of 64,000, 61,500, 57,000 and 54,000. Electrophoresis of S-carboxylmethylated (SCM)-fibrous protein results in two major bands of approximately 57,000 and 64,000. SDS gels of the two preparations of keratohyalin and the SCM-fibrous protein were compared with gels of the insoluble proteins of granular and eluted cornified cells. All of the major bands in the preparations of keratohyalin can be seen in gels of the granular preparation. The two SCM-fibrous protein bands correspond with two prominent bands in gels of the cornified cell preparation. Two bands of the citric acid-extracted keratohyalin sample also have the same mobility. The major band of the potassium phosphate-extracted preparation of keratohyalin corresponds with a third prominent band of the cornified cell preparation. These results suggest that biochemical components of the preparations of keratohyalin are present in both the granular and the cornified layers of newborn rat epidermis.


Asunto(s)
Electroforesis en Gel de Poliacrilamida , Proteínas/análisis , Piel/análisis , Aminoácidos/análisis , Animales , Animales Recién Nacidos , Detergentes , Histocitoquímica , Hialina/análisis , Peso Molecular , Fosfatos , Potasio , Proteínas/aislamiento & purificación , Ratas , Dodecil Sulfato de Sodio , Ácidos Tricarboxílicos
9.
J Invest Dermatol ; 66(4): 230-5, 1976 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-818319

RESUMEN

Two proteins have been identified in extracts of fetal rat skin which are related to the two major fibrous proteins of newborn rat stratum corneum. The relative amount of these proteins increases daily from the 16th to the 20th day (d) of gestation when judged by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and immunoelectrophoresis using antibody to the purified fibrous protein. Two-dimensional analysis by SDS-polyacrylamide gel electrophoresis and immunoelectrophoresis demonstrates that these two proteins are the only cross-reactive species in the fetal skin from 16d to 19d development. Some additional lower-molecular-weight components can be detected at 20d and 21d. In double-diffusion analysis, cross-reactive proteins in 19d fetal extracts show partial identity but have fewer antigenic sites than proteins in 20d extracts. The 20d protein shows a reaction of identity with purified newborn fibrous protein. Immunofluorescence studies on fetal skin support the prescence of cross-reacting components at 16d development related to the newborn fibrous protein. Intensity of fluorescence increases at 18d and 20d in the spinous and granular cell cytoplasm and in the keratohyaline granules. The stratum corneum, first seen at 20d, is intensely fluorescent. The cellular localization and time of appearance of the cross-reactive proteins suggest that they may be associated with tonofilaments.


Asunto(s)
Proteínas/aislamiento & purificación , Piel/embriología , Animales , Electroforesis en Gel de Poliacrilamida , Femenino , Técnica del Anticuerpo Fluorescente , Edad Gestacional , Inmunodifusión , Inmunoelectroforesis , Ratas , Piel/análisis
10.
J Periodontol ; 52(9): 465-76, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7026753

RESUMEN

This review leads to a concept in which the tissues of the dentogingival junction are dynamic rather that static. Even when they are pathologic, they can be reconstituted by repair. Both their cellular and extracellular components exhibit a high rate of turnover. Some of the cells are specialized for specific functions, such as attachment formation, and do not generate additional cells, but generative pools are always nearby. The cells are capable of movement and of positional change. The junctional epithelium can advance and retract. The cuticle width is alterable. The entire tissue is capable of regeneration after wounding. This dynamic group of tissues is well adapted for the healing of direct injuries produced during mastication. The tissues do remarkably well, over long periods, in their response to periodontal disease, whether due to direct bacterial or toxic damage, or to indirect damage via the migration of inflammatory cells into the lesion. The tissues show a capacity for repair and regeneration following the elimination of plaque formation and the resultant resolution of the inflammatory infiltrate. The complete story is not yet developed. The past 60 years are replete with fine contributions by distinguished workers. Additional contributions continue to be made. The inheritance from our predecessors has been used well and our expanded knowledge in this area now serves as the conceptual framework for further study.


Asunto(s)
Inserción Epitelial/anatomía & histología , Encía/anatomía & histología , Periodoncio/anatomía & histología , Animales , Gatos , Bovinos , Tejido Conectivo/patología , Esmalte Dental/anatomía & histología , Esmalte Dental/ultraestructura , Perros , Inserción Epitelial/patología , Inserción Epitelial/ultraestructura , Encía/ultraestructura , Humanos , Enfermedades Periodontales/patología , Bolsa Periodontal/patología , Ratas , Cicatrización de Heridas
11.
Spine (Phila Pa 1976) ; 9(7): 769-71, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6390723

RESUMEN

This study describes the changes in chymopapain-specific IgE antibody levels in patients following chemonucleolysis with Chymodiactin. Using the ChymoFAST method, chymopapain-specific IgE values were studied in 91 patients prior to and for 2 months post-Chymodiactin chemonucleolysis. A total of 8.8% (17/91) developed IgE levels greater than or equal to 0.06 IU/ml. Those patients with detectable IgE levels prior to chemonucleolysis were more likely than those with nondetectable preinjection levels (36.4% versus 4%) to develop chymopapain-specific IgE levels greater than or equal to 0.06 IU/ml.


Asunto(s)
Quimopapaína/efectos adversos , Hipersensibilidad a las Drogas/etiología , Endopeptidasas/efectos adversos , Inmunoglobulina E/inmunología , Desplazamiento del Disco Intervertebral/tratamiento farmacológico , Especificidad de Anticuerpos , Quimopapaína/uso terapéutico , Hipersensibilidad a las Drogas/inmunología , Humanos , Técnicas para Inmunoenzimas , Inmunoglobulina E/análisis
12.
Arch Oral Biol ; 27(7): 535-45, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6751303

RESUMEN

The indirect fluorescent-antibody technique was used to locate histidine-rich basic protein, filaggrin. In the newborn, immunofluorescence was seen in the cornified layers and in keratohyalin granules throughout the mouth using antibody specific for epidermal filaggrin, a distribution similar to that in epidermis where it is thought that filaggrin functions as the keratin matrix protein. In the adult immunofluorescence was in keratohyalin granules of palate, buccal and tongue epithelium but in the stratum corneum was limited to the soft palate with weak, patchy areas in the densely keratinized epithelium of the hard palate and tongue. Immunofluorescence was delineated at the boundary between the soft and hard palates. A protein apparently identical to epidermal filaggrin was identified in extracts of newborn palate by its mobility on sodium dodecyl sulphate-polyacrylamide gels and subsequent reaction with the antibody used for immunofluorescent studies. This protein was not detected in extracts of adult oral epithelia. Both newborn and adult tissues contained high mol. wt cross-reactive protein, suggestive of the filaggrin-precursor protein extractable from keratohyalin granules. The distribution of filaggrin was consistent with its function as a keratin matrix protein in the newborn oral epithelium and some less densely keratinized regions of the adult. However, in the adult mouth, filaggrin is not detectable in the stratum corneum of the most densely keratinized regions. Thus, the protein must be lost or its antigenic sites altered with maturation of the animal, depending on the type and extent of keratinization.


Asunto(s)
Proteínas de Filamentos Intermediarios , Boca/análisis , Proteínas/análisis , Envejecimiento , Animales , Animales Recién Nacidos , Electroforesis en Gel de Poliacrilamida , Epidermis/análisis , Epitelio/análisis , Proteínas Filagrina , Técnica del Anticuerpo Fluorescente , Ratas , Ratas Endogámicas
13.
Harefuah ; 125(5-6): 136-8, 192, 1993 Sep.
Artículo en Hebreo | MEDLINE | ID: mdl-8225090

RESUMEN

A mixed-grain, high-fiber cereal (Disivit) prepared from oats, corn, wheat and soybean was used to treat 20 patients with chronic constipation and 22 with hypercholesterolemia in double-blind, cross-over trials. Disivit (50 g/d, containing 12.5 g dietary fiber) was given to the constipated patients for 2 weeks and then a low-fiber placebo for another 2 weeks, and similarly for the hypercholesterolemic patients. In those with constipation, the frequency of bowel movements increased significantly, stools became softer and laxative intake decreased. In hypercholesterolemic patients serum cholesterol decreased significantly, but only by 15%. Thus the fiber cereal appears to be a suitable treatment for constipation, while for hypercholesterolemia a larger dose or a longer period of treatment may be required.


Asunto(s)
Estreñimiento/dietoterapia , Fibras de la Dieta/uso terapéutico , Grano Comestible , Hipercolesterolemia/dietoterapia , Colesterol/sangre , Enfermedad Crónica , Método Doble Ciego , Humanos , Hipercolesterolemia/sangre
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