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1.
Phys Rev Lett ; 108(9): 092502, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22463628

RESUMO

We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate.

2.
Phys Rev Lett ; 105(21): 212502, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21231294

RESUMO

We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for x>1, which is sensitive to short-range contributions to the nuclear wave function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the "superfast" quarks probed at x>1. The falloff at x>1 is noticeably stronger in 2H and 3He, but nearly identical for all heavier nuclei.

3.
Phys Rev Lett ; 103(20): 202301, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-20365978

RESUMO

New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from (2)H, (3)He, (4)He, (9)Be and (12)C for 0.3 < x < 0.9, Q(2) approximately 3-6 GeV(2). These data represent the first measurement of the EMC effect for (3)He at large x and a significant improvement for (4)He. The data do not support previous A-dependent or density-dependent fits to the EMC effect and suggest that the nuclear dependence of the quark distributions may depend on the local nuclear environment.

4.
Phys Rev Lett ; 85(22): 4682-6, 2000 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-11082626

RESUMO

The cross section for straight phi meson photoproduction on the proton has been measured for the first time up to a four-momentum transfer -t = 4 GeV2, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. At low four-momentum transfer, the differential cross section is well described by Pomeron exchange. At large four-momentum transfer, above -t = 1.8 GeV2, the data support a model where the Pomeron is resolved into its simplest component, two gluons, which may couple to any quark in the proton and in the straight phi.

5.
J Clin Pharmacol ; 21(7): 280-3, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7263925

RESUMO

The concept that urinary 6-hydroxycortisol excretion patterns reflect all microsomal enzyme activities remains a subject of controversy. Three different microsomal hydroxylase activities were therefore studied in rat liver after the animals were intoxicated with alcohol, phenobarbital, or a combination thereof. The activities of pentobarbital hydroxylase, aniline hydroxylase, and cortisol 6-hydroxylase (the enzyme metabolizing cortisol to 6-hydroxycortisol) were assayed simultaneously after each treatment. A heterogeneity of enzyme activities was noted. Cortisol 6-hydroxylase activity did not parallel the activity patterns of the two other hydroxylases. The data suggest that before urinary 6-hydroxycortisol excretion patterns can be utilized as an index of microsomal enzyme induction, the effect of the specific drug on individual cytochrome P-450 hydroxylases is required.


Assuntos
Sistema Enzimático do Citocromo P-450 , Indução Enzimática/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Anilina Hidroxilase/biossíntese , Animais , Interações Medicamentosas , Etanol/farmacologia , Masculino , Oxigenases de Função Mista/biossíntese , Pentobarbital/biossíntese , Fenobarbital/farmacologia , Ratos , Esteroide Hidroxilases
6.
Phys Rev Lett ; 99(24): 242502, 2007 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-18233444

RESUMO

We have measured the nuclear transparency of the A(e,e'pi+) process in 2H, 12C, 27Al, 63Cu, and 197Au targets. These measurements were performed at the Jefferson Laboratory over a four momentum transfer squared range Q2=1.1 to 4.7 (GeV/c)2. The nuclear transparency was extracted as the super-ratio of (sigmaA/sigmaH) from data to a model of pion-electroproduction from nuclei without pi-N final-state interactions. The Q2 and atomic number dependence of the nuclear transparency both show deviations from traditional nuclear physics expectations and are consistent with calculations that include the quantum chromodynamical phenomenon of color transparency.

7.
Phys Rev Lett ; 98(14): 142301, 2007 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-17501267

RESUMO

We report on a study of the longitudinal to transverse cross section ratio, R=sigmaL/sigmaT, at low values of x and Q2, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Laboratory Hall C spanning the four-momentum transfer range 0.06

8.
Gastroenterology ; 70(3): 382-4, 1976 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-55371

RESUMO

Immunological reactivity in alcoholic hepatitis has bben attributed to alcoholic hyalin, the histological hallmark of this disease. A purified isolate of alcoholic hyalin with electron microscopic, biochemical, and serological characteristics documented previously was added to lymphocytes from healthy subjects and patients with alcoholic hepatitis or other hepatic disorders. Production of migration inhibition factor (MIF) in response to this material was used as an index to lymphocyte reactivity. MIF was significantly increased in lymphocytes obtained from patients with alcoholic hepatis, as compared to the healthy controls (P less than 0.001), and persons with other liver diseases (P less than 0.005). These observations indicate that immunological hyperreactivity to alcoholic hyalin occurs in patients with alcoholic hepatitis; such activity may be of key importance in the pathogenesis or sequelae (or both) of this disease.


Assuntos
Alcoolismo/complicações , Hepatite/imunologia , Hialina/imunologia , Imunidade Celular , Hepatite/etiologia , Humanos , Linfócitos/imunologia , Linfócitos/metabolismo , Fatores Inibidores da Migração de Macrófagos/biossíntese , Linfócitos T/imunologia , Linfócitos T/metabolismo
9.
Gastroenterology ; 73(6): 1374-6, 1977 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-72017

RESUMO

Alcoholic hyalin was prepared from postmortem livers of patients with alcoholic liver disease. Alcoholic hyalin was purified by discontinuous sucrose density gradient ultracentrifugation. The purified protein preparation contained about 12% reducing sugar, the remainder being protein. Gel filtration on Sephadex 4B column showed the presence of three peaks. Each peak material thus obtained contained acetylglucosamine, hexosamine, and deoxysugar (calculated as rhamnose). That these protein components followed by scanning the gels at 280 nm, and at 520 nm after staining the gels with periodic acid-Schiff base reagent for the presence of carbohydrate.


Assuntos
Antígenos/análise , Hepatite Alcoólica/imunologia , Hialina/análise , Fígado/análise , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Humanos , Fígado/imunologia
10.
J Nutr ; 106(5): 606-14, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-944244

RESUMO

The effects of a single, oral, intoxicating dose of ethanol (EtOH, 9 g/kg body weight) on the distribution of water- and fat-soluble vitamins in various subcellular fractions of eight rat livers and eight rat brains was surveyed. Results were compared to eight other rats receiving a similar dose of saline (controls). Both organs showed redistribution of vitamins among the various organelles after EtOH was given. In saline-treated animals the nucleus and cytosol of the liver contained the highest proportion of all vitamins and the microsomes and lysosomes contained the least. As compared to controls, EtHO ingestion generally caused the mitochondria and microsomes to accumulate vitamins, while vitamins in the lysosomes were decreased. A different pattern was seen in the brain after EtOH administration. Except for thiamin and niacin, the whole brain vitamins were higher than those in controls; they were primarily concentrated in the brain nucleus and mitochondria. It was concluded that changes in the organelle vitamin content of the liver were the result of EtOH injury. The simultaneous attempt to repair the injury was manifested by the by the sequestration of vitamins in the organelles of EtOH-treated animals as compared to controls.


Assuntos
Intoxicação Alcoólica/metabolismo , Encéfalo/metabolismo , Fígado/metabolismo , Complexo Vitamínico B/metabolismo , Vitaminas/metabolismo , Animais , Ácido Ascórbico/metabolismo , Encéfalo/efeitos dos fármacos , Núcleo Celular/metabolismo , Citosol/metabolismo , Humanos , Fígado/efeitos dos fármacos , Masculino , Microssomos/metabolismo , Microssomos Hepáticos/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias Hepáticas/metabolismo , Ratos , Frações Subcelulares/metabolismo , Vitamina A/metabolismo , Vitamina E/metabolismo
11.
Phys Rev Lett ; 91(21): 212302, 2003 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-14683292

RESUMO

The forward-backward asymmetry in np-->dpi(0), which must be zero in the center-of-mass system if charge symmetry is respected, has been measured to be [17.2+/-8.0(stat)+/-5.5(syst)]x10(-4), at an incident neutron energy of 279.5 MeV. This observable is compared to recent chiral effective field theory calculations, with implications regarding the du quark mass difference.

12.
Phys Rev Lett ; 91(12): 122002, 2003 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-14525355

RESUMO

We report new measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, G(n)(E)/G(n)(M), obtained via recoil polarimetry from the quasielastic 2H(e-->,e(')n-->)1H reaction at Q2 values of 0.45, 1.13, and 1.45 (GeV/c)(2) with relative statistical uncertainties of 7.6% and 8.4% at the two higher Q2 points, which points have never been achieved in polarization measurements.

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