Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Klin Khir ; (1): 32-4, 2014 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-24923147

RESUMEN

The degrees of invasiveness, proliferative activity, morphofunctional activity of nuclei in the thyroidal gland tumors were studied, while analyzing material, obtained in 1343 patients, suffering thyroidal gland cancer (THGC) and operated on in 2000-2013 yrs. Morphological point quantity of malignancy (as a criterion of the tumor progression grade) and mitotic activity in cellular population were determined in various kinds of THGC. Undifferentiated (anaplastic carcinoma) type of THGC is the most malignant one. There were determined a spindle-like, giant-cell and squamous-cell forms of undifferentiated THGC. The presence of sites of differentiated cancer in 33% of histological preparations witnesses the interrelationship with the earlier existed pathological process.


Asunto(s)
Carcinoma/epidemiología , Glándula Tiroides/patología , Neoplasias de la Tiroides/epidemiología , Carcinoma/patología , Carcinoma/cirugía , Carcinoma Neuroendocrino , Carcinoma Papilar , Femenino , Humanos , Incidencia , Metástasis Linfática , Masculino , Persona de Mediana Edad , Necrosis , Invasividad Neoplásica , Cáncer Papilar Tiroideo , Carcinoma Anaplásico de Tiroides , Glándula Tiroides/cirugía , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Ucrania
2.
J Environ Radioact ; 75(3): 267-83, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15193793

RESUMEN

In the present study, an effort is attempted to record the impact of chronic radiation on natural aquatic populations exposed to protracted doses (lower if compared to intervention levels but higher if compared to typical background) and to chemical pollution. The methodology is based on the analyses of chromosome aberrations observed in cells. Therefore, some preliminary research results on the cytogenetic effects on aquatic organisms of various taxa, in coastal ecosystems are presented, considering some selective regions of elevated natural gamma radiation and conventional pollution. These areas are the geothermal spring areas in the island of Ikaria-Eastern Aegean Sea and the port of Pireus, in Greece. The data are compared to the findings recorded in some organisms collected from the North Aegean Sea the early period after the Chernobyl accident. With regard to the different species examined, a first evaluation of the results is made using the reported field findings for the wide area of Chernobyl. The environmental assessment of the studied areas in terms of radiation impact is based on the cytogenetic injuries observed, and evidence of ecosystem disturbance is also pointed out. The final environmental assessment based on the quantified effects observed in the organisms from the studied areas takes into account a published conceptual model of zones of radiation dose rates and the resulting organism responses in a step function scale.


Asunto(s)
Ecosistema , Genética de Población , Centrales Eléctricas , Traumatismos por Radiación/veterinaria , Ceniza Radiactiva/efectos adversos , Liberación de Radiactividad Peligrosa , Contaminantes Químicos del Agua/envenenamiento , Animales , Citogenética , Daño del ADN , Monitoreo del Ambiente , Grecia , Invertebrados , Dinámica Poblacional , Ucrania , Abastecimiento de Agua
3.
Vestn Khir Im I I Grek ; 138(5): 13-6, 1987 May.
Artículo en Ruso | MEDLINE | ID: mdl-3672727

RESUMEN

An experience of the clinic with the surgical treatment of diffuse toxic goiter associated with autoimmune thyroiditis for the recent 16 years has been generalized based upon 258 observations. Long-term results followed in 73.6% of the patients show that an improved method of operation thought to be less radical gives good results. An immune depressive effect of the operation was noted. The investigation facilitates positive solution of the problem of the expediency of the surgical treatment of the complicated form of toxic goiter having indications for surgery.


Asunto(s)
Enfermedad de Graves/cirugía , Tiroidectomía , Tiroiditis Autoinmune/complicaciones , Adolescente , Adulto , Anciano , Femenino , Enfermedad de Graves/complicaciones , Humanos , Masculino , Persona de Mediana Edad
4.
Klin Khir ; (11): 7-9, 2001 Nov.
Artículo en Ruso | MEDLINE | ID: mdl-11944261

RESUMEN

The elaborated method of colorectal anastomosis formation was applied for the intestinal continuity restoration after its resection for obturative colonic tumoral ileus. Insufficiency of anastomotic sutures was not revealed. Postoperative complications had occurred in 2 (6.9%) of patients. All the patients have survived.


Asunto(s)
Neoplasias del Colon/complicaciones , Neoplasias del Colon/cirugía , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Derivación Yeyunoileal/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
J Phys Condens Matter ; 21(41): 415502, 2009 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-21693989

RESUMEN

Single-crystalline films of Lu(3)Al(5)O(12):Bi, prepared by the liquid phase epitaxy method from the melt-solution based on Bi(2)O(3) flux, have been studied at 4.2-400 K by time-resolved luminescence spectroscopy methods. Their emission spectra consist of two types of bands with strongly different characteristics. The ultraviolet emission band consists of two components, arising from the electronic transitions which correspond to the [Formula: see text] and [Formula: see text] transitions in a free Bi(3+) ion. At low temperatures, mainly the lower-energy component of this emission is observed, having the decay time∼10(-3) s at T<100 K and arising from the metastable (3)P(0) level. At T>100 K, the higher-energy emission component appears, arising from the thermally populated emitting (3)P(1) level. The visible emission spectrum consists of two dominant strongly overlapped broad bands with large Stokes shifts. At 4.2 K, their decay times are ∼10(-5) s and decrease with increasing temperature. Both of the visible emission bands are assumed to have an exciton origin. The lower-energy band is ascribed to an exciton, localized near a single Bi(3+) ion. The higher-energy band shows a stronger intensity dependence on the Bi(3+) content and is assumed to arise from an exciton localized near a dimer Bi(3+) center. The origin and structure of the corresponding excited states is considered and the processes, taking place in the excited states, are discussed.

7.
Phys Rev Lett ; 101(18): 182502, 2008 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18999823

RESUMEN

We present experimental results of the first high-precision test of quark-hadron duality in the spin-structure function g_{1} of the neutron and 3He using a polarized 3He target in the four-momentum-transfer-squared range from 0.7 to 4.0 (GeV/c);{2}. Global duality is observed for the spin-structure function g_{1} down to at least Q;{2}=1.8 (GeV/c);{2} in both targets. We have also formed the photon-nucleon asymmetry A1 in the resonance region for 3He and found no strong Q2 dependence above 2.2 (GeV/c);{2}.

8.
Phys Rev Lett ; 101(2): 022303, 2008 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-18764175

RESUMEN

We present a measurement of the spin-dependent cross sections for the 3He over -->(e over -->,e')X reaction in the quasielastic and resonance regions at a four-momentum transfer 0.1< or =Q2< or =0.9 GeV2. The spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt-Cottingham and extended Gerasimov-Drell-Hearn sum rules for the first time. The data are also compared to an impulse approximation calculation and an exact three-body Faddeev calculation in the quasielastic region.

9.
Phys Rev Lett ; 96(2): 022003, 2006 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-16486563

RESUMEN

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from 4He at an average scattering angle = 5.7 degrees and a four-momentum transfer Q2 = 0.091 GeV2 . From these data, for the first time, the strange electric form factor of the nucleon G(E)s can be isolated. The measured asymmetry of A(PV) = (6.72 +/- 0.84(stat) +/- 0.21(syst) x 10(-6) yields a value of G(E)s = -0.038 +/- 0.042(stat) +/- 0.010(syst), consistent with zero.

10.
Phys Rev Lett ; 95(14): 142002, 2005 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-16241646

RESUMEN

We present the first measurement of the Q2 dependence of the neutron spin structure function g2(n) at five kinematic points covering 0.57 (GeV/c)2 < or = Q2 < or = 1.34 (GeV/c)2 at x approximately = 0.2. Though the naive quark-parton model predicts g2 = 0, nonzero values occur in more realistic models of the nucleon which include quark-gluon correlations, finite quark masses, or orbital angular momentum. When scattering from a noninteracting quark, g2(n) can be predicted using next-to-leading order fits to world data for g1(n). Deviations from this prediction provide an opportunity to examine QCD dynamics in nucleon structure. Our results show a positive deviation from this prediction at lower Q2, indicating that contributions such as quark-gluon interactions may be important. Precision data obtained for g1(n) are consistent with next-to-leading order fits to world data.

11.
Probl Endokrinol (Mosk) ; 31(4): 13-6, 1985.
Artículo en Ruso | MEDLINE | ID: mdl-3840258

RESUMEN

A study of 190 patients with diffuse toxic goiter combined with autoimmune thyroiditis has revealed some clinical features: a torpid course and a solid-elastic consistency of the thyroid. In 37.4% of the cases autoimmune thyroiditis was combined with a severe form of thyrotoxicosis. The combined form of diffuse toxic goiter correlated with a greater frequency of the detection of thyroid autoantibodies to thyroglobulin and microsomal antigen (in 83 and 78.3% of the patients respectively) as compared to the common form of diffuse toxic goiter (in 47.3 and 48.1%). A study of the hormonal thyroid status of 43 patients with diffuse toxic goiter combined with autoimmune thyroiditis showed that T3, T4 and TTH levels in patients with the presence of autoantibodies to thyroid antigens did not differ from the levels of these hormones in the common form of diffuse toxic goiter, and in the group of the patients with the absence of autoantibodies there was a tendency to the development of T3-toxicosis. The absence of pathognomic symptoms in combined forms of diffuse toxic goiter makes their preoperative diagnosis difficult. Interrelationship of the hormonal thyroid status and humoral antithyroid immunity was noted.


Asunto(s)
Enfermedades Autoinmunes/complicaciones , Enfermedad de Graves/complicaciones , Tiroiditis/complicaciones , Adolescente , Adulto , Anciano , Autoanticuerpos/análisis , Enfermedades Autoinmunes/fisiopatología , Niño , Femenino , Enfermedad de Graves/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Tiroglobulina/inmunología , Glándula Tiroides/fisiopatología , Tiroiditis/fisiopatología
12.
Phys Rev Lett ; 85(14): 2900-4, 2000 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-11005963

RESUMEN

We have measured the transverse asymmetry A(T') in 3He(e,e(')) quasielastic scattering in Hall A at Jefferson Laboratory with high precision for Q2 values from 0.1 to 0.6 (GeV/c)(2). The neutron magnetic form factor G(n)(M) was extracted based on Faddeev calculations for Q2 = 0.1 and 0.2 (GeV/c)(2) with an experimental uncertainty of less than 2%.

13.
Phys Rev Lett ; 93(15): 152301, 2004 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-15524867

RESUMEN

The generalized forward spin polarizabilities gamma(0) and delta(LT) of the neutron have been extracted for the first time in a Q2 range from 0.1 to 0.9 GeV2. Since gamma(0) is sensitive to nucleon resonances and delta(LT) is insensitive to the Delta resonance, it is expected that the pair of forward spin polarizabilities should provide benchmark tests of the current understanding of the chiral dynamics of QCD. The new results on delta(LT) show significant disagreement with chiral perturbation theory calculations, while the data for gamma(0) at low Q2 are in good agreement with a next-to-leading-order relativistic baryon chiral perturbation theory calculation. The data show good agreement with the phenomenological MAID model.

14.
Phys Rev Lett ; 92(2): 022301, 2004 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-14753931

RESUMEN

We have measured the spin structure functions g(1) and g(2) of 3He in a double-spin experiment by inclusively scattering polarized electrons at energies ranging from 0.862 to 5.058 GeV off a polarized 3He target at a 15.5 degrees scattering angle. Excitation energies covered the resonance and the onset of the deep inelastic regions. We have determined for the first time the Q2 evolution of Gamma(1)(Q2)= integral (1)(0)g(1)(x,Q2)dx, Gamma(2)(Q2)= integral (1)(0)g(2)(x,Q2)dx, and d(2)(Q2)= integral (1)(0)x(2)[2g(1)(x,Q2)+3g(2)(x,Q2)]dx for the neutron in the range 0.1< or =Q2< or =0.9 GeV2 with good precision. Gamma(1)(Q2) displays a smooth variation from high to low Q2. The Burkhardt-Cottingham sum rule holds within uncertainties and d(2) is nonzero over the measured range.

15.
Phys Rev Lett ; 86(14): 2975-9, 2001 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-11290086

RESUMEN

We present measurements of the recoil proton polarization for the d(gamma-->,p-->)n reaction at straight theta(c.m.) = 90 degrees for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. The induced polarization p(y) vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polarization transfer Cx does not vanish above 1 GeV, inconsistent with hadron helicity conservation. Thus, we show that the scaling behavior observed in the d(gamma,p)n cross sections is not a result of perturbative QCD. These data should provide important tests of new nonperturbative calculations in the intermediate energy regime.

16.
Phys Rev Lett ; 91(5): 052301, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12906589

RESUMEN

We have measured the proton recoil polarization in the 4He(e-->,e(')p-->)4H reaction at Q(2)=0.5, 1.0, 1.6, and 2.6 (GeV/c)(2). The measured ratio of polarization transfer coefficients differs from a fully relativistic calculation, favoring the inclusion of a medium modification of the proton form factors predicted by a quark-meson coupling model. In addition, the measured induced polarizations agree reasonably well with the fully relativistic calculation indicating that the treatment of final-state interactions is under control.

17.
Phys Rev Lett ; 88(9): 092301, 2002 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-11863996

RESUMEN

The ratio of the electric and magnetic form factors of the proton G(E(p))/G(M(p)), which is an image of its charge and magnetization distributions, was measured at the Thomas Jefferson National Accelerator Facility (JLab) using the recoil polarization technique. The ratio of the form factors is directly proportional to the ratio of the transverse to longitudinal components of the polarization of the recoil proton in the elastic e(-->)p---> e(-->)p reaction. The new data presented span the range 3.5< Q(2)< 5.6 GeV(2) and are well described by a linear Q(2) fit. Also, the ratio sqrt[Q(2)] F(2(p))/F(1(p)) reaches a constant value above Q(2) = 2 GeV(2).

18.
Phys Rev Lett ; 89(24): 242301, 2002 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-12484938

RESUMEN

We present data on the inclusive scattering of polarized electrons from a polarized 3He target at energies from 0.862 to 5.06 GeV, obtained at a scattering angle of 15.5 degrees. Our data include measurements from the quasielastic peak, through the nucleon resonance region, and beyond, and were used to determine the virtual photon cross-section difference sigma(1/2)-sigma(3/2). We extract the extended Gerasimov-Drell-Hearn integral for the neutron in the range of four-momentum transfer squared Q2 of 0.1-0.9 GeV2.

20.
Phys Rev Lett ; 87(24): 242501, 2001 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-11736498

RESUMEN

We present the first precision measurement of the spin-dependent asymmetry in the threshold region of 3He(e,e') at Q2 values of 0.1 and 0.2 (GeV/c)2. The agreement between the data and nonrelativistic Faddeev calculations which include both final-state interactions and meson-exchange current effects is very good at Q2 = 0.1 (GeV/c)2, while a small discrepancy at Q2 = 0.2 (GeV/c)2 is observed.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA