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1.
Appl Opt ; 54(11): 3491-7, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25967342

RESUMEN

We report experimental results on the production and characterization of asymmetric and composite supersonic gas flows, created by merging independently controllable flows from multiple nozzles. We demonstrate that the spatial profiles are adjustable over a large range of parameters, including gas density, density gradient, and atomic composition. The profiles were precisely characterized using three-dimensional tomography. The creation and measurement of complex gas flows is relevant to numerous applications, ranging from laser-produced plasmas to rocket thrusters.

2.
Phys Rev Lett ; 110(15): 155003, 2013 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-25167278

RESUMEN

We report the generation of MeV x rays using an undulator and accelerator that are both driven by the same 100-terawatt laser system. The laser pulse driving the accelerator and the scattering laser pulse are independently optimized to generate a high energy electron beam (>200 MeV) and maximize the output x-ray brightness. The total x-ray photon number was measured to be ∼1×10(7), the source size was 5 µm, and the beam divergence angle was ∼10 mrad. The x-ray photon energy, peaked at 1 MeV (reaching up to 4 MeV), exceeds the thresholds of fundamental nuclear processes (e.g., pair production and photodisintegration).

3.
Sci Rep ; 7(1): 16603, 2017 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-29192189

RESUMEN

High-energy X-rays (HEX-rays) with photon energies on order of 100 keV have attractive characteristics, such as comparably low absorption, high spatial resolution and the ability to access inner-shell states of heavy atoms. These properties are advantageous for many applications ranging from studies of bulk materials to the investigation of materials in extreme conditions. Ultrafast X-ray diffraction allows the direct imaging of atomic dynamics simultaneously on its natural time and length scale. However, using HEX-rays for ultrafast studies has been limited due to the lack of sources that can generate pulses of sufficiently short (femtosecond) duration in this wavelength range. Here we show single-crystal diffraction using ultrashort ~90 keV HEX-ray pulses generated by an all-optical source based on inverse Compton scattering. We also demonstrate a method for measuring the crystal lattice spacing in a single shot that contains only ~105 photons in a spectral bandwidth of ~50% full width at half maximum (FWHM). Our approach allows us to obtain structural information from the full X-ray spectrum. As target we use a cylindrically bent Ge crystal in Laue transmission geometry. This experiment constitutes a first step towards measurements of ultrafast atomic dynamics using femtosecond HEX-ray pulses.

4.
Sci Rep ; 6: 24622, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27090440

RESUMEN

The recent combination of ultra-intense lasers and laser-accelerated electron beams is enabling the development of a new generation of compact x-ray light sources, the coherence of which depends directly on electron beam emittance. Although the emittance of accelerated electron beams can be low, it can grow due to the effects of space charge during free-space propagation. Direct experimental measurement of this important property is complicated by micron-scale beam sizes, and the presence of intense fields at the location where space charge acts. Reported here is a novel, non-destructive, single-shot method that overcame this problem. It employed an intense laser probe pulse, and spectroscopic imaging of the inverse-Compton scattered x-rays, allowing measurement of an ultra-low value for the normalized transverse emittance, 0.15 (±0.06) π mm mrad, as well as study of its subsequent growth upon exiting the accelerator. The technique and results are critical for designing multi-stage laser-wakefield accelerators, and generating high-brightness, spatially coherent x-rays.

5.
Artículo en Ruso | MEDLINE | ID: mdl-6978588

RESUMEN

Examinations of the changes in the parameters of the reaction of clotted blood morphological dissociation (CBMDR) occuring in the acutest period of ischemic cerebral stroke were carried out over time. Regular changes of those parameters were revealed, these changes depending on the disease gravity and time course. In graver forms and course of the ischemic stroke a diminution of the volume of the IIId blood-clotting fraction and a shortening of the time of its formation were observed. As the patients' state improved in the course of the conservative treatment given, the above parameters gradually approached those observed in the control group. On the contrary a deterioration of the patients' state led to a rapid diminution of the IIId fraction volume and shortening of the time of its formation. The changes of the CBMDR parameters allow one to judge about the gravity of ischemic cerebral stroke and the time course of the pathological process, as well as to assess the efficacy of the therapy given.


Asunto(s)
Coagulación Sanguínea , Isquemia Encefálica/sangre , Enfermedad Aguda , Pruebas de Coagulación Sanguínea , Isquemia Encefálica/etiología , Femenino , Humanos , Hipertensión/complicaciones , Arteriosclerosis Intracraneal/complicaciones , Masculino , Enfermedades Reumáticas/complicaciones
6.
Artículo en Ruso | MEDLINE | ID: mdl-7435053

RESUMEN

In 61 patients with hemorrhagic stroke, hypocoagulation was revealed in the acute period of the disease. This was done by using the reaction of morphological dissociation of coagulated blood (RMDCB). The degree of the hypocoagulation was found to depend on the gravity and the duration of the disease. The graver the state of the patient in the most acute period, the more marked the hypocoagulation, and vice versa. The improvement of patients under the influence of complex treatment was accompanied with an approach of the RMDCB parameters to those of the control group. Thus, the RMDCB may be recommended for use in broad clinical practice for evaluating the state of the blood coagulation system in the final stage of hemocoagulation.


Asunto(s)
Coagulación Sanguínea , Hemorragia Cerebral/sangre , Enfermedad Aguda , Pruebas de Coagulación Sanguínea , Femenino , Humanos , Masculino
7.
Artículo en Ruso | MEDLINE | ID: mdl-7124235

RESUMEN

The authors studied for the first time changes in the parameters of the coagulated blood morphological dissociation test (CBMDT) in 234 patients with stroke in the most acute period. They revealed a stable dependence between the character and extent of the changes in the CBMDT and the form and severity of the stroke and the time course of the pathological process. Changes in the main CBMDT parameters in hemorrhagic stroke were diametrically opposite to those in ischemic stroke: an increase in the volume and the time of formation of three blood coagulation fractions (TBCF) was revealed in hemorrhave and, on the contrary, a decrease in the TBCF value and the time of its precipitation in ischemia. The extent of these shifts was determined by the severity of the disease. According to the authors' findings severe forms of stroke differ in the TBCF volume in 96% of cases and in the time of sedimentation in 81%. In a moderately severe stroke the respective figures were 15 and 79% and in diseases following a satisfactory course in 9 and 74% of cases. The severity of the pathological process may be judged by and its time course studied from the changes in the CBMDT parameters.


Asunto(s)
Pruebas de Coagulación Sanguínea , Isquemia Encefálica/sangre , Hemorragia Cerebral/sangre , Enfermedad Aguda , Diagnóstico Diferencial , Humanos
8.
Vestn Khir Im I I Grek ; 139(12): 3-8, 1987 Dec.
Artículo en Ruso | MEDLINE | ID: mdl-3333897

RESUMEN

The article describes the achievements of transfusiology in the USSR for the period from 1917 till 1987. The leading role of Soviet scientists in the development of all main problems of the present-day transfusiological science and practice is stressed.


Asunto(s)
Transfusión Sanguínea/historia , Hematología/historia , Bancos de Sangre/historia , Historia del Siglo XX , Humanos , U.R.S.S.
9.
Vestn Khir Im I I Grek ; 140(6): 3-7, 1988 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-3222858

RESUMEN

The author considers different aspects of perestroika in medical science and health protection concerned with surgery and transfusiology which are necessary for improving the quality and effectiveness of medical aid to people.


Asunto(s)
Transfusión Sanguínea/tendencias , Cirugía General/tendencias , Transfusión Sanguínea/normas , Cirugía General/normas , Humanos , Calidad de la Atención de Salud/tendencias , U.R.S.S.
10.
Vestn Khir Im I I Grek ; 142(6): 92-5, 1989 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-2510392

RESUMEN

Based on their personal experience and analysis of literature data the authors elucidate the significance of achievements of the present-day immunohematology in surgical practice: in blood transfusion, allotransplantation, the connection of surgical diseases with group antigens of blood.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Incompatibilidad de Grupos Sanguíneos/etiología , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Sistema del Grupo Sanguíneo Rh-Hr/inmunología , Procedimientos Quirúrgicos Operativos/efectos adversos , Reacción a la Transfusión , Trasplante Homólogo/efectos adversos , Incompatibilidad de Grupos Sanguíneos/prevención & control , Tipificación y Pruebas Cruzadas Sanguíneas , Prueba de Histocompatibilidad , Humanos
11.
Vestn Khir Im I I Grek ; 123(9): 15-9, 1979 Sep.
Artículo en Ruso | MEDLINE | ID: mdl-505866

RESUMEN

The authors report on the diagnostic value of the reaction of morphological dissociation of the coagulated blood, which, in addition to other clinico-rentgen-laboratory data, can be used as an additional and helpful hematological test for differential diagnosis in a mechanical jaundice of various geneses (obstructive jaundice, hepatocirrhosis, malignant tumors).


Asunto(s)
Células Sanguíneas/fisiología , Coagulación Sanguínea , Colestasis/diagnóstico , Adulto , Anciano , Pruebas de Coagulación Sanguínea , Colestasis/etiología , Colestasis/fisiopatología , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
12.
Vestn Khir Im I I Grek ; 120(2): 128-31, 1978 Feb.
Artículo en Ruso | MEDLINE | ID: mdl-644769

RESUMEN

The authors studied the indices of the serumal ferrum (total ferrum of the blood serum, total ferrum-binding ability of the blood serum and transferrin saturation with ferrum) before and at different terms after the exfusion of 400 cc of blood for the autotransfusion in planned surgical interventions upon 30 cases of pulmonary cancer, 21 cases of carcinoma of the stomach and 16 orthopedic cases. The same study was carried out upon a control group of normal individuals after exfusion of 400 cc of donor blood. Characteristic changes of the serumal ferrum metabolism due to the loss of a certain amount of hemoglobin after the exfusion were found in differen patients and in normal individuals.


Asunto(s)
Transfusión de Sangre Autóloga , Hierro/sangre , Articulación de la Cadera/cirugía , Humanos , Artropatías/sangre , Artropatías/cirugía , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/cirugía , Neoplasias Gástricas/sangre , Neoplasias Gástricas/cirugía
13.
Vestn Khir Im I I Grek ; 137(9): 32-5, 1986 Sep.
Artículo en Ruso | MEDLINE | ID: mdl-3787974

RESUMEN

The effect of autotransfusions of blood irradiated by long-wave UV rays on the system of hemostasis was studied in 22 patients with ulcer disease of the stomach and duodenum. It was shown that transfusion of the autoblood irradiated by long-wave UV rays in a certain dosage decreased the hemostatic potential of blood improving its rheological properties and facilitated the stimulation of reparative processes.


Asunto(s)
Coagulación Sanguínea/efectos de la radiación , Transfusión de Sangre Autóloga , Úlcera Péptica/terapia , Terapia Ultravioleta , Adulto , Sangre/efectos de la radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica/sangre
14.
Vestn Khir Im I I Grek ; 133(10): 114-8, 1984 Oct.
Artículo en Ruso | MEDLINE | ID: mdl-6516149

RESUMEN

The indications, contraindications, variants and methods of autohemotransfusions as well as problems of their use in surgery, urology and other fields are discussed in detail on the basis of great clinical experience (about 3000 autohemotransfusions).


Asunto(s)
Transfusión de Sangre Autóloga , Procedimientos Quirúrgicos Operativos , Adolescente , Adulto , Anciano , Conservación de la Sangre , Transfusión de Sangre Autóloga/métodos , Venodisección , Humanos , Persona de Mediana Edad , Cuidados Preoperatorios , Factores de Tiempo
15.
Vestn Khir Im I I Grek ; 148(6): 321-7, 1992 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-1302981

RESUMEN

Under study was the influence of different regimens of blood photomodification on the course of the tumor process. Experiments were carried out on 460 syngeneic mice with a model of Lewis adenocarcinoma of lungs and melanoma B 16. It was established that the influence of APMB on the course of the tumor process is dose-dependent and when specially selected the regimen of APMB may have an antitumoral effect. The transfusion of the photomodified donor blood may facilitate the suppression of antitumoral immune reaction of the recipient organism.


Asunto(s)
Adenocarcinoma/terapia , Transfusión de Sangre Autóloga/métodos , Sangre/efectos de la radiación , Terapia por Láser , Neoplasias Pulmonares/terapia , Melanoma Experimental/terapia , Adenocarcinoma/mortalidad , Animales , Transfusión de Sangre Autóloga/instrumentación , Estudios de Evaluación como Asunto , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/secundario , Melanoma Experimental/mortalidad , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Factores de Tiempo
16.
Vestn Khir Im I I Grek ; 134(6): 122-6, 1985 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-4049653

RESUMEN

On the basis of personal clinical experience and literature data the authors show the necessity to formulate indications for transfusion therapy and its prognosis not by nosological but by pathogenetic principle, i. e. in relation to pathophysiological changes in the patient, similar in different diseases and traumas.


Asunto(s)
Transfusión Sanguínea , Procedimientos Quirúrgicos Operativos , Volumen Sanguíneo , Cuidados Críticos/métodos , Enfermedades Hematológicas/terapia , Humanos , Sustitutos del Plasma/administración & dosificación , Cuidados Preoperatorios/métodos , Toxemia/terapia
17.
Vestn Khir Im I I Grek ; 140(6): 117-9, 1988 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-3222848

RESUMEN

The authors have determined indications and contraindications for using the method of haemotherapy based upon their experience with more than 1200 transfusions of photomodified autoblood under conditions of the hospital and 84 AUVIBs under the ambulatory conditions. The treatment of non-complicated forms of ulcer disease of the stomach and duodenum is shown to be possible under the ambulatory conditions, cicatrization of the ulcers developing 2-3 times more rapidly than under the currently used treatment of the ulcer disease under conditions of the hospital.


Asunto(s)
Transfusión de Sangre Autóloga , Sangre/efectos de la radiación , Úlcera Péptica/radioterapia , Terapia Ultravioleta , Adolescente , Adulto , Atención Ambulatoria , Femenino , Humanos , Masculino , Úlcera Péptica/sangre , Cicatrización de Heridas/efectos de la radiación
18.
Vestn Khir Im I I Grek ; 141(8): 99-101, 1988 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-3232308

RESUMEN

Photometric measurements have shown that during UV irradiation of autoblood in the apparatus "Izolda" the dose of the falling UV irradiation does not remain constant. It becomes less with the term of work of the quartz-mercury lamp and at the expense of the film formed on the walls of the quartz flask of blood cells and plasma components. Therefore for the comparative assessment of the biological and clinical effects in photomodification of autoblood and its transfusion it is necessary to measure the dose of the falling UVI.


Asunto(s)
Transfusión de Sangre Autóloga , Sangre/efectos de la radiación , Procedimientos Quirúrgicos Operativos , Terapia Ultravioleta , Diseño de Equipo , Humanos , Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/métodos , Radiometría/instrumentación , Radiometría/métodos , Dosificación Radioterapéutica , U.R.S.S.
20.
Vestn Khir Im I I Grek ; 144(8): 114-7, 1989 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-2603292

RESUMEN

The authors studied the influence of daylight upon peroxidase activity and lipid content in neutrophils by means of cytochemical reactions in blood smears. In the experimental series of studies the blood was taken and stored without daylight. Control blood samples were kept under normal conditions. The studies have shown daylight to be a potent activator of redox processes and lipid metabolism in neutrophils. Similar effect upon peroxidase activity and lipid content in neutrophils is exerted by one calculated dose of long-wave UV rays, two doses inhibiting these processes. Taking and storing blood without daylight contributes to longer valuable morphological and functional condition of the formed elements.


Asunto(s)
Transfusión Sanguínea , Lípidos/sangre , Neutrófilos/efectos de la radiación , Peroxidasas/sangre , Luz Solar , Rayos Ultravioleta , Conservación de la Sangre , Oscuridad , Humanos , Lípidos/efectos de la radiación , Neutrófilos/metabolismo , Oxidación-Reducción/efectos de la radiación , Peroxidasas/efectos de la radiación , Factores de Tiempo
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