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1.
Phys Rev Lett ; 128(13): 132002, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426724

RESUMO

The first measurement of lepton-jet momentum imbalance and azimuthal correlation in lepton-proton scattering at high momentum transfer is presented. These data, taken with the H1 detector at HERA, are corrected for detector effects using an unbinned machine learning algorithm (multifold), which considers eight observables simultaneously in this first application. The unfolded cross sections are compared with calculations performed within the context of collinear or transverse-momentum-dependent factorization in quantum chromodynamics as well as Monte Carlo event generators.

2.
Georgian Med News ; (271): 122-127, 2017 Oct.
Artigo em Russo | MEDLINE | ID: mdl-29099714

RESUMO

Roots and rhizomes of Vinca herbacea Waldst. et Kit, were collected during early flowering and fruiting. Рhenophases biologically active substances I and II were obtained by liquid-liquid extraction. Dominant alkaloids: tabersonin, reserpine, maidine, norfluorocurarin and copsinin were obtained after the dispertion in citrare-phosfhate buffer and subsequent TLC. Accelerated restitution of granulocytopoiesis was observed in mice during both irradiation and myelotoxic drug-induced acute leucopenia. Increase in total WBC over 200% was observed after treatment by substance I in drug-induced leucopenia model (fivefold oral administration) and over 130% after treatment by substance I in irradiate mice (fivefold intraperitoneal administration). Morphological and anatomical structures of the underground organs of V. herbacea have been studied. The main microstructural characteristics are revealed - Rhizomes are characterized by coutinized epidermis, lamellar collenchyma, fibers and the texture of the vascular system of a monocyclic structure. The root system shows the whole cortex, the endoderm with Kaspar spots; the outer, radially continuous phloem tissue is located in the conducting system and distinguishes the cylindrical xylem tissue with annular and spiral-circular blood vessels.


Assuntos
Alcaloides de Vinca/análise , Vinca/química , Animais , Citostáticos/toxicidade , Feminino , República da Geórgia , Leucopenia/sangue , Leucopenia/tratamento farmacológico , Leucopenia/etiologia , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Lesões Experimentais por Radiação/tratamento farmacológico , Lesões Experimentais por Radiação/etiologia , Rizoma/química , Testes de Toxicidade Aguda , Alcaloides de Vinca/farmacologia , Alcaloides de Vinca/toxicidade
3.
Georgian Med News ; (264): 127-1311, 2017 Mar.
Artigo em Russo | MEDLINE | ID: mdl-28480864

RESUMO

Antiseizure activity of Cephalaria gigantea root extract was studied using PTZ- and/or audiogenic seizure models in outbred Wistar and inbred Krouchinsky- Molodkina rats respectively. In PTZ - model onset of tonic- clonic seizures, latencies to the beginning of the seizure activity, and mortality, and similarly in audiogenic seizures behavioral convulsive reactions , facial automatisms and latency to wild running were evaluated. The extract is used traditionally in Georgian folk medicine as anticonvulsant drug. In this study it was evidenced experimentally that extract demonstrates anticonvulsant properties as in both model, as in both routs of administration - peroral and intraperitoneal. Extract appeared most effective in case of preliminary repetitive administration: in PTZ model seizures were eliminated in 9 of 10 animals, and in audiogenic model convulsive response was no more observable during 7 days of treatment termination. It was found also that sedative properties are characteristic of this antiseizure extract according to the sleeping prolongation in barbiturate treated mice. Safety of the extract was evaluated in toxicological acute and chronic experiments, and consequently it is considered a substance of moderate general toxicity.


Assuntos
Anticonvulsivantes/uso terapêutico , Dipsacaceae/química , Extratos Vegetais/uso terapêutico , Convulsões/tratamento farmacológico , Estimulação Acústica , Animais , Anticonvulsivantes/química , Anticonvulsivantes/toxicidade , Feminino , Hipnóticos e Sedativos/química , Hipnóticos e Sedativos/uso terapêutico , Hipnóticos e Sedativos/toxicidade , Masculino , Camundongos , Pentilenotetrazol , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Ratos Wistar , Convulsões/etiologia
4.
Eur Phys J C Part Fields ; 77(11): 791, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31997933

RESUMO

The strong coupling constant α s is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of α s ( m Z ) at the Z-boson mass m Z are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be α s ( m Z ) = 0.1157 ( 20 ) exp ( 29 ) th . Complementary, α s ( m Z ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value α s ( m Z ) = 0.1142 ( 28 ) tot obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations.

5.
Georgian Med News ; (207): 43-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22859449

RESUMO

Granulocytopoietic response to lithium carbonate (Li+) in rat was eliminated completely by N-cholinergic blocking agent, and independently by alpha-1-adrenergic antagonist. A link between these two contradictory events is explained by release of acetylcholine from the cholinergic preganglionic nerve endings in adrenal medulla triggered by Li+, and subsequent discharge of catecholamines (CA) from medullar chromaffin cells, which on their part activate adrenergic receptors of alpha-1 class on hematopoietic progenitor cells. Respectively, granulocytopoietic response to Li+ is blocked by cholinergic N-blocking agent at the level of adrenal medulla, and by the alpha-adrenergic blocking agent at the level of the hematopoietic cells proper. The stimulatory action of Li+ on granulocytopoietic cells is indirect, while is mediated by CA release from adrenal chromaffine cells. At the initial stages of leukocyte restitution in the acute myelotoxic leucopenia relative increase in "large" lymphocyte fraction (Lge) preceding the increment in granulocyte counts is evident. In this fraction of lymphocytes peripheral blood progenitor cells (PBPC) are expected.


Assuntos
Acetilcolina/metabolismo , Catecolaminas , Células Precursoras de Granulócitos/efeitos dos fármacos , Carbonato de Lítio/administração & dosagem , Medula Suprarrenal/efeitos dos fármacos , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Animais , Benzoatos/administração & dosagem , Catecolaminas/metabolismo , Antagonistas Colinérgicos/administração & dosagem , Células Cromafins/efeitos dos fármacos , Ciclofosfamida/toxicidade , Doxazossina/administração & dosagem , Células Precursoras de Granulócitos/citologia , Leucopenia/induzido quimicamente , Masculino , Ratos , Receptores Colinérgicos/metabolismo
7.
Artigo em Russo | MEDLINE | ID: mdl-10750190

RESUMO

The present study was aimed at comparative electrophysiological, clinical, and neurophysiological assessment of the brain functional state in dextrals (50 men) and sinistrals (5 men), who participated in the Chernobyl clean. The patients were observed over the course of 10 years (from 1990 to 1999). The results of examination of healthy persons (20 dextrals and 10 sinistrals) were used as a control. The clinical examination revealed the earlier manifestation and more severe development of paroxysmal and epileptic seizures in sinistrals than in dextrals. Electrophysiological study showed a progressive decrease in interhemispheric asymmetry of the EEG coherence characteristic for a healthy brain to inversion of its sign. These changes were more pronounced in sinistrals. In the remote terms after radiation, the interhemispheric EEG coherence decreased over the whole cortex, especially, in the frontal and central areas in both groups of patients. Neurophysiological study revealed a progressive impairment of voluntary motor activity and tactile sensibility, especially, in the left hand. These defects were more expressed in sinistrals than in dextrals. The results of complex and longitudinal examination suggest that the observed changes in brain asymmetry and interhemispheric interaction can be not only a result of a dysfunction of subcortical limbic-reticular and mediobasal brain structures but also a result of the white matter damage including corpus callosum. More expressed impairments in sinistrals than in dextrals can be explained by specific morphofunctional organization of the brain in persons with different sensor and motor asymmetries.


Assuntos
Dominância Cerebral/efeitos da radiação , Atividade Nervosa Superior/efeitos da radiação , Centrais Elétricas , Liberação Nociva de Radioativos , Adulto , Dominância Cerebral/fisiologia , Eletroencefalografia/métodos , Eletroencefalografia/efeitos da radiação , Eletroencefalografia/estatística & dados numéricos , Eletrofisiologia , Atividade Nervosa Superior/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Estatísticas não Paramétricas , Fatores de Tempo , Ucrânia
9.
Artigo em Russo | MEDLINE | ID: mdl-9778816

RESUMO

The present study was aimed at the comparative assessment of electrophysiological and clinical data in persons (155 right-handed men) who took part in the Chernobyl clean-up in different periods after radiation. Dynamic evaluation of psychoneurological disorders revealed the growth of incidence and severity of cerebrovascular disturbances accompanied by the signs of organic symptoms' aggravation and encephalopathy in longer periods after radiation. The results of neuropsychological examination also showed the deterioration of patients' state manifested as growth of fatigue, cognitive defects, and emotional impairments. Analysis of the EEG parameters, including power and coherence mapping and 3-d dipole source localization analysis demonstrated the increasing number of patients with the most severe forms of EEG pathology: the "plane" type in combination with fast paroxysmal (beta-band) and slow forms of activity from 45% in 1990-92 to 63% in 1997. The "hypersynchronization" type of EEG activity was typical for the earlier period accompanied by the dominance of the pathological forms of EEG activity in mediobasal structures of the left hemisphere, and brainstem zones vs. diencephalon and the right hemisphere. The later period was characterized by decreasing coherence in symmetrical frontal and front-temporal areas of the left hemisphere, while in the early period the hypersynchronization prevailed in symmetrical central areas and in the right hemisphere. The evidence were obtained to a disconnection between the brain hemispheres. We suppose that the progressive involvement of structures of the limbic-reticular complex (especially, brainstem, mediobasal structures, and white matter) into the pathological process occurs with time in participants of clean-up of the Chernobyl disaster consequences.


Assuntos
Encéfalo/efeitos da radiação , Centrais Elétricas , Liberação Nociva de Radioativos , Adulto , Encéfalo/fisiopatologia , Dominância Cerebral/fisiologia , Dominância Cerebral/efeitos da radiação , Eletroencefalografia/métodos , Eletroencefalografia/efeitos da radiação , Atividade Nervosa Superior/fisiologia , Atividade Nervosa Superior/efeitos da radiação , Humanos , Masculino , Pessoa de Meia-Idade , Neuropsicologia , Lesões por Radiação/diagnóstico , Lesões por Radiação/fisiopatologia , Lesões por Radiação/psicologia , Processamento de Sinais Assistido por Computador , Fatores de Tempo , Ucrânia
10.
Zh Vyssh Nerv Deiat Im I P Pavlova ; 46(4): 699-711, 1996.
Artigo em Russo | MEDLINE | ID: mdl-8984808

RESUMO

We examined 23 patients (participants in the clean-up of the consequences of the Chernobyl accident in 1986-1987) using neuropsychological and electrophysiological approaches. The results obtained by means of EEG coherence analysis, three-dimensional source localization, and dichotic listening test were compared. All the patients showed some common dysfunctions such as disturbances of hemispheric interaction which resulted in deterioration of the brain functional state in comparison with the control group. Neuropsychological evidence and source localization of the epileptiform EEG suggested predominantly subcortical damage at the limbic-reticular and, especially, diencephalic level. The observed signs of the left-hemispheric dysfunction depended on the brainstem damage while the right-hemispheric dysfunction were explained by the diencephalic damage. The observed symptoms were considered as a result of subcortical brain lesions at different levels rather than the primary cortical hemispheric damage.


Assuntos
Encéfalo/efeitos da radiação , Eletroencefalografia/efeitos da radiação , Exposição Ocupacional/efeitos adversos , Centrais Elétricas , Liberação Nociva de Radioativos , Adulto , Encéfalo/fisiopatologia , Dominância Cerebral/fisiologia , Dominância Cerebral/efeitos da radiação , Eletroencefalografia/métodos , Atividade Nervosa Superior/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuropsicologia , Doses de Radiação , Fatores de Tempo , Ucrânia
11.
Brain Topogr ; 8(2): 161-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8793126

RESUMO

EEG power mapping, coherence analysis, source localization of epileptiform activity and psychoneurological investigations were performed in 100 patients (males, 25-45 years old, right-handed), who took part in the cleaning of the Chernobyl disaster in 1986-1987, and compared with a control group (healthy persons of the same age). Neuropsychological studies showed autonomic, endocrine, emotional and other disorders in all patients. About 70% of all patients had paroxysmal EEG activity and intermittent seizures sometimes associated with loss of consciousness. EEG power mapping showed higher than normal levels of alpha- and theta-bands power, mainly in the frontal and central areas in the one group of patients. In others, power was lower especially in alpha-band. Paroxysmal waves of alpha- and theta-bands had localization of dipole sources at deeper near midline levels, and as a rule with a shift to the right hemisphere. Paroxysmal beta-waves demonstrated sources of a diffuse character at a more basal level with a shift to the left hemisphere. Interhemispheric coherences had lower values in the frontal and higher in the central leads than in healthy persons. Intrahemispheric coherences were decreased in the left hemisphere and increased in the right, opposite to that in controls.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Centrais Elétricas , Liberação Nociva de Radioativos , Adulto , Eletroencefalografia , Humanos , Masculino , Pessoa de Meia-Idade , Ucrânia
13.
Artigo em Russo | MEDLINE | ID: mdl-8256539

RESUMO

Posttraumatic hydrocephalus is an active progressive process of excessive accumulation of cerebrospinal fluid due to liquorodynamic disturbances following cerebrocranial injury. In addition to clinical assessments, it is necessary to use special diagnostic techniques to define indications for bypass surgeries which are an effective therapy for progressive posttraumatic hydrocephalus.


Assuntos
Lesões Encefálicas/diagnóstico , Lesões Encefálicas/cirurgia , Hidrocefalia/diagnóstico , Hidrocefalia/cirurgia , Doença Aguda , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Lesões Encefálicas/complicações , Derivações do Líquido Cefalorraquidiano , Criança , Pré-Escolar , Feminino , Humanos , Hidrocefalia/classificação , Hidrocefalia/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Cintilografia , Tomografia Computadorizada por Raios X
15.
Patol Fiziol Eksp Ter ; (5): 19-21, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2293153

RESUMO

Similar distortion of hypertensive response to epinephrine occurred in sarcoma-45-bearing rats, Walker carcinosarcoma-bearing rats, and hepatectomized rats. The response in the last-named was distorted on the 3rd postoperative day. The hypertensive response to epinephrine was restored after the regenerative processes in the liver were completed (7th-10th postoperative day). Distortion of the response in carcinosarcoma-bearing rats was detected beginning from the 4th day after transplantation in some of the animals and on the 14th day in the others; in all sarcoma 45-bearing rats distortion occurred by the 20th day. The pressor response was distorted usually under conditions of pharmacological block of the alpha-adrenergic receptors. It is assumed that in extensive proliferation of normal and neoplastic cells, substances exerting a selective blocking effect on the alpha-adrenoceptors of the blood vessels penetrate into circulation.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Carcinoma 256 de Walker/fisiopatologia , Epinefrina/farmacologia , Fígado/fisiologia , Sarcoma Experimental/fisiopatologia , Animais , Feminino , Hepatectomia , Masculino , Ratos
16.
Eksp Onkol ; 12(5): 29-32, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2171898

RESUMO

Sensitivity to phenylephrine, isoproterenol, serotonin, oxytocin, acetylcholine and barium chloride of vas deferens uterus und fundus strip was studied comparatively in hepatectomized and sarcoma-45, sarcoma-M1, Walker carcinosarcoma and Zajdela ascites hepatoma bearing rats. The contractile response to monoamines and oxytocin was considerably lower or absent at certain periods after hepatectomy or tumour grafting. Effects of biogenic amine antagonists were also substantially altered. The response to isoproterenol, acetylcholine and barium chloride remained unchanged. Apparently a selective alteration of a response of visceral smooth muscles mediated through alpha-adrenergic and D-serotonin receptors occurred not only during the tumour growth but also in the case of active (extensive) proliferation of the normal tissue.


Assuntos
Carcinoma 256 de Walker/fisiopatologia , Epinefrina/fisiologia , Neoplasias Hepáticas Experimentais/fisiopatologia , Fígado/fisiologia , Músculo Liso/efeitos dos fármacos , Receptores Adrenérgicos/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Sarcoma Experimental/fisiopatologia , Animais , Feminino , Fundo Gástrico/efeitos dos fármacos , Hepatectomia , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/fisiopatologia , Transplante de Neoplasias , Ratos , Receptores de Catecolaminas , Fatores de Tempo , Útero/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacos
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