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2.
Rev Assoc Med Bras (1992) ; 67(12): 1779-1784, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34909949

RESUMEN

OBJECTIVE: The study aimed to investigate the use of Neutrophil/lymphocyte ratio, C-reactive protein/albumin ratio, controlling nutritional status, and prognostic nutritional index immune, inflammatory, and malnutrition markers Metabolic syndrome+ in sarcoidosis patients, as an early-stage marker. METHOD: This is a single-center and cross-sectional study that determines the association of Metabolic syndrome in patients with sarcoidosis. Patients were evaluated based on the National Cholesterol Education Program's Adult Treatment Panel III criteria. Neutrophil/lymphocyte ratio, C-reactive protein/albumin ratio, controlling nutritional status, and prognostic nutritional index values were simultaneously determined through blood test. RESULTS: A total of 253 patients diagnosed with sarcoidosis were included in this study. Metabolic syndrome- was detected in 37.2% of patients. The prevalence was significantly higher in females (p<0.001). Any degree of malnutrition assessed by controlling nutritional status had higher Metabolic syndrome (p=0.035). The Neutrophil/lymphocyte ratio cutoff value was 2.24, sensitivity was 70.53, specificity was 60.13, and Area Under the Curve value was 0.663 for predicting Metabolic syndrome in sarcoidosis patients. CONCLUSION: Neutrophil/lymphocyte ratio and controlling nutritional status are associated with the Metabolic syndrome+ in sarcoidosis patients. Thus, close monitoring of Neutrophil/lymphocyte ratio and controlling nutritional status increase in terms of Metabolic syndrome and immune malnutrition may be important in sarcoidosis patients.


Asunto(s)
Desnutrición , Síndrome Metabólico , Sarcoidosis , Estudios Transversales , Femenino , Humanos , Desnutrición/diagnóstico , Desnutrición/epidemiología , Síndrome Metabólico/complicaciones , Síndrome Metabólico/epidemiología , Evaluación Nutricional , Estado Nutricional , Pronóstico , Sarcoidosis/complicaciones , Sarcoidosis/epidemiología
3.
Phys Rev Lett ; 98(19): 193601, 2007 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-17677620

RESUMEN

We demonstrate the reversible mapping of a coherent state of light with a mean photon number (-)n approximately equal to 1.1 to and from the hyperfine states of an atom trapped within the mode of a high-finesse optical cavity. The coherence of the basic processes is verified by mapping the atomic state back onto a field state in a way that depends on the phase of the original coherent state. Our experiment represents an important step toward the realization of cavity QED-based quantum networks, wherein coherent transfer of quantum states enables the distribution of quantum information across the network.

4.
Phys Rev Lett ; 97(8): 083602, 2006 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-17026303

RESUMEN

Localization to the ground state of axial motion is demonstrated for a single, trapped atom strongly coupled to the field of a high finesse optical resonator. The axial atomic motion is cooled by way of coherent Raman transitions on the red vibrational sideband. An efficient state detection scheme enabled by strong coupling in cavity QED is used to record the Raman spectrum, from which the state of atomic motion is inferred. We find that the lowest vibrational level of the axial potential with zero-point energy variant Planck's over 2 h omega a/2kB = 13 microK is occupied with probability P0 approximately 0.95.

5.
Nature ; 436(7047): 87-90, 2005 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-16001065

RESUMEN

At low temperatures, sufficiently small metallic and semiconductor devices exhibit the 'Coulomb blockade' effect, in which charge transport through the device occurs on an electron-by-electron basis. For example, a single electron on a metallic island can block the flow of another electron if the charging energy of the island greatly exceeds the thermal energy. The analogous effect of 'photon blockade' has been proposed for the transport of light through an optical system; this involves photon-photon interactions in a nonlinear optical cavity. Here we report observations of photon blockade for the light transmitted by an optical cavity containing one trapped atom, in the regime of strong atom-cavity coupling. Excitation of the atom-cavity system by a first photon blocks the transmission of a second photon, thereby converting an incident poissonian stream of photons into a sub-poissonian, anti-bunched stream. This is confirmed by measurements of the photon statistics of the transmitted field. Our observations of photon blockade represent an advance over traditional nonlinear optics and laser physics, into a regime with dynamical processes involving atoms and photons taken one-by-one.

6.
Phys Rev Lett ; 93(23): 233603, 2004 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-15601159

RESUMEN

The transmission spectrum for one atom strongly coupled to the field of a high finesse optical resonator is observed to exhibit a clearly resolved vacuum Rabi splitting characteristic of the normal modes in the eigenvalue spectrum of the atom-cavity system. A new Raman scheme for cooling atomic motion along the cavity axis enables a complete spectrum to be recorded for an individual atom trapped within the cavity mode, in contrast to all previous measurements in cavity QED that have required averaging over 10(3)-10(5) atoms.

7.
Science ; 303(5666): 1992-4, 2004 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-14988512

RESUMEN

A single cesium atom trapped within the mode of an optical cavity is used to generate single photons on demand. The photon wave packets are emitted as a Gaussian beam with temporal profile and repetition rate controlled by external driving fields. Each generation attempt is inferred to succeed with a probability near unity, whereas the efficiency for creating an unpolarized photon in the total cavity output is 0.69 +/- 0.10, as limited by passive cavity losses. An average of 1.4 x 10(4) photons are produced by each trapped atom. These results constitute an important step in quantum information science, for example, toward the realization of distributed quantum networking.

8.
Nature ; 425(6955): 268-71, 2003 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-13679909

RESUMEN

Conventional lasers (from table-top systems to microscopic devices) typically operate in the so-called weak-coupling regime, involving large numbers of atoms and photons; individual quanta have a negligible impact on the system dynamics. However, this is no longer the case when the system approaches the regime of strong coupling for which the number of atoms and photons can become quite small. Indeed, the lasing properties of a single atom in a resonant cavity have been extensively investigated theoretically. Here we report the experimental realization of a one-atom laser operated in the regime of strong coupling. We exploit recent advances in cavity quantum electrodynamics that allow one atom to be isolated in an optical cavity in a regime for which one photon is sufficient to saturate the atomic transition. The observed characteristics of the atom-cavity system are qualitatively different from those of the familiar many-atom case. Specifically, our measurements of the intracavity photon number versus pump intensity indicate that there is no threshold for lasing, and we infer that the output flux from the cavity mode exceeds that from atomic fluorescence by more than tenfold. Observations of the second-order intensity correlation function demonstrate that our one-atom laser generates manifestly quantum (nonclassical) light, typified by photon anti-bunching and sub-poissonian photon statistics.

9.
Nature ; 423(6941): 731-4, 2003 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-12802329

RESUMEN

Quantum information science attempts to exploit capabilities from the quantum realm to accomplish tasks that are otherwise impossible in the classical domain. Although sufficient conditions have been formulated for the physical resources required to achieve quantum computation and communication, there is a growing understanding of the power of quantum measurement combined with the conditional evolution of quantum states for accomplishing diverse tasks in quantum information science. For example, a protocol has recently been developed for the realization of scalable long-distance quantum communication and the distribution of entanglement over quantum networks. Here we report the first enabling step in the realization of this protocol, namely the observation of quantum correlations for photon pairs generated in the collective emission from an atomic ensemble. The nonclassical character of the fields is demonstrated by the violation of an inequality involving their normalized correlation functions. Compared to previous investigations of non-classical correlations for photon pairs produced in atomic cascades and in parametric down-conversion, our experiment is distinct in that the correlated photons are separated by a programmable time interval (of about 400 nanoseconds in our initial experiments).

10.
Artif Organs ; 20(3): 218-26, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8694692

RESUMEN

The possibility that the discharge coefficient (Cd) for a mechanical heart valve (MHV) is affected by valvular stenosis is addressed. A 29 mm bileaflet (Si. Jude Medical) mitral valve is tested on a cardiovascular duplicator (CVD) in its normal state and under two degrees of simulated stenosis. Stenoticity is simulated by bracing the occluders such that full opening is impossible. The pressure drop through the valve is described by a two-term second-order polynomial in flow, from which it is shown that the Cd should be a nonlinear function of the flow rate through the valve. The average difference between measured and calculated areas decreased from 74%, when a constant value of 0.7 was used for the Cd, to 3.7%, when the Cd was a nonlinear function of the flow rate.


Asunto(s)
Prótesis Valvulares Cardíacas , Estenosis de la Válvula Mitral/fisiopatología , Modelos Biológicos , Circulación Cerebrovascular/fisiología , Presión , Análisis de Regresión
11.
Physiologist ; 34(1 Suppl): S100-1, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2047400

RESUMEN

Different histochemical reactions were searched in the digestive tract of rats that flighted on Soviet biosatellites, 5, 7, 13, 14 and 18 1/2 days (2). Space flight decreased glycoprotein (GP) content of sublingual glands and of gastric and intestinal mucosa, and increased reactions for leucin-aminopeptidase (LAP) and acid phosphatase (ACP) of the small intestine. These responses were in relation with the duration of the flight. For searching some possible mechanism by which they occurred, same investigations were done in rats submitted at soil level to a contention hypokinesia (HK), for mimicking space flight. After HK, similar histochemical responses were founded as after the true flight. The evolution of histochemical responses paralleled the corticosterone hypersecretion, suggesting a causal correlation, but they were also the same in adrenalectomised rats. Effectory hormonal pathways are thus further to be searched, as well as a correlation with the intermediary metabolism, as a similar evolution was founded in pancreatic, insulin secreting, B cells.


Asunto(s)
Sistema Digestivo/metabolismo , Vuelo Espacial , Animales , Corticosterona/sangre , Glicoproteínas/metabolismo , Histocitoquímica , Ratas , Factores de Tiempo , Ingravidez/efectos adversos
13.
Physiologie ; 26(1): 3-6, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2502782

RESUMEN

In rats recovered after 13 days of cosmic flight a diminution of acid and neutral glycoproteins was observed in the gastric mucosa and proximal segments of the small intestine: the decrease was less evident in the sublingual glands and colon. Leucine aminopeptidase and acid phosphatase in the small intestine were intensified. No significant changes were observed in the other enzymes investigated. Acid phosphatase showed a more intense activity in the endocrine pancreas B cells. The alterations observed after 13 days of flight in the "Cosmos 1887" biosatellite are significant but less marked than after 18 days of flight, and more accentuated than after 5-7 days of flight.


Asunto(s)
Sistema Digestivo/metabolismo , Vuelo Espacial , Animales , Enzimas/metabolismo , Glicoproteínas/metabolismo , Histocitoquímica , Masculino , Ratas , Factores de Tiempo , U.R.S.S.
16.
Physiologie ; 24(3): 179-86, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3116566

RESUMEN

Wistar rats (110-125 g) were irradiated with a single dose of 500 R. Histochemical studies were done concerning the glycoproteins (GP) of sublingual glands, gastric, small intestine and colon mucosa, and some intestinal enzymes: acid and alkaline phosphatase (ACP, ALP) leucineaminopeptidase (LAP), Mg-dependent ATP-ase, NADH-diaphorase, lactic dehydrogenase (LDH). After irradiation all these reactions were diminished, with a maximal effect between 3-5 days. This impairment is in accord with the maximal lethality in this interval after such a degree of irradiation that produced the gastrointestinal syndrome. Cocarboxylase, a radioprotector, improved these changes regarding the structures of the small intestine and also the GP of sublingual glands, stomach, small intestine and colon, demonstrating there its efficiency.


Asunto(s)
Sistema Digestivo/efectos de la radiación , Glicoproteínas/análisis , Hidrolasas/análisis , Oxidorreductasas/análisis , Animales , Colon/efectos de la radiación , Sistema Digestivo/análisis , Sistema Digestivo/enzimología , Mucosa Gástrica/efectos de la radiación , Histocitoquímica , Intestino Delgado/efectos de la radiación , Masculino , Ratas , Ratas Endogámicas , Glándula Sublingual/efectos de la radiación
17.
Physiologie ; 24(3): 187-90, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3116567

RESUMEN

From the histochemical investigation carried out on the digestive tract of rats after 7 days space flight in the soviet biosatellite Cosmos 1667 it resulted that neutral and acid glycoproteins diminished slightly in the sublingual gland, stomach, small intestine and the colon. Some intestinal enzymes augmented (leucineaminopeptidase, acid phosphatase, adenosinetriphosphatase and glucose-6-phosphatase). The changes observed after this flight were less marked than after an 18 day flight (in the Soviet biosatellite Cosmos 936 and 1129) and similar to those revealed after 7 days of hypokinesia. The glycoprotein changes were close to those observed after a 5-day flight (Cosmos 1514) but in which there were pregnant rats; after these last flights, the enzymes were not studied.


Asunto(s)
Sistema Digestivo/análisis , Glicoproteínas/análisis , Hidrolasas/análisis , Vuelo Espacial , Animales , Sistema Digestivo/enzimología , Histocitoquímica , Ratas , Ratas Endogámicas
18.
Physiologie ; 23(2): 73-83, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3088618

RESUMEN

Hypokinesia (HK) produced by a 7-day contention of pregnant rats in small cages is followed by a discrete decrease of PAS reaction for glycoproteins in the submandibular and sublingual glands, in the mucosa of the stomach, duodenum, small intestine and colon, and also by a small but evident increase of that for leucineaminopeptidase and acid phosphatase in the duodenum and in the intestine. The moderation of these reactions may be explained by the small interval of contention, and not by pregnancy, because the changes are similar in male rats after the same interval. After a longer interval, these reactions change in the same manner but they are more evident, as results from our previous studies. They are not connected with a corticosterone hypersecretion (the principal glucocorticoid in rat) because adrenalectomy does not influence them as results from our previous research. HK increases the 4 and 5 isoenzymes of lactic dehydrogenase (LDH) in the stomach. In the small intestine appeared only the LDH 4 and 5 isoenzymes, HK increases LDH5 isoenzyme. Adrenalectomy increases all LDH isoenzymes of gastric mucosa, and in the small intestine all five fractions appeared, but with a slight activity of LDH 1 and 2. This relation between adrenal hormones and these isoenzymes must be further studied, especially after HK. After a 7-day HK, nonpregnant female rats present an augmented total gastric acid output (TAO), as previously found by us in males. After adrenalectomy this acid hypersecretion disappeared. Even smaller values for TAO were found. Pregnancy considerably increased TAO which may be due, as we have already found, to a blood pH decrease. After HK this hypersecretion decreased remaining nevertheless great. Progeni born of rats submitted to HK have, after 30 days of life, an augmented TAO. Parts of this research were carried out in order to reproduce by HK, at ground level, the 5-day orbital flight conditions of the soviet Cosmos 1514 biosatellite containing pregnant rats in which we studied some identical parameters.


Asunto(s)
Fenómenos Fisiológicos del Sistema Digestivo , Preñez , Equilibrio Ácido-Base , Glándulas Suprarrenales/fisiología , Animales , Femenino , Ácido Gástrico/metabolismo , Histocitoquímica , Intestinos/enzimología , Isoenzimas , L-Lactato Deshidrogenasa/análisis , Embarazo , Ratas , Restricción Física , Vuelo Espacial , Estómago/enzimología , Factores de Tiempo
19.
Physiologie ; 23(2): 85-9, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3088619

RESUMEN

Investigations were carried out in the digestive tract of pregnant rats submitted to 5 days orbital flight, as well as in rats aged 30 and 100 days, to which the pregnant experimental rats had given birth. The flight produces, in pregnant rats, a mild reduction of the glycoproteins of the salivary glands, of the gastric mucosa and the goblet cells of the small intestine, as well as an augmented activity of some intestinal enzymes. The progeny born after flight presents at 30 days a mild decrease of the glycoproteins in the sublingual gland and stomach and a slight increase in the activity of some enzymes in the small intestine. In 100-day-old rats, the differences between control and experimental group are not significant.


Asunto(s)
Sistema Digestivo/enzimología , Preñez , Vuelo Espacial , Animales , Femenino , Histocitoquímica , Intestino Delgado/enzimología , Masculino , Embarazo , Ratas , Ratas Endogámicas , Glándulas Salivales/enzimología , Factores de Tiempo , U.R.S.S.
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