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1.
Phys Rev Lett ; 110(13): 131802, 2013 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-23581310

RESUMEN

The beauty to up quark coupling constant |V(ub)| can be extracted from B → ρ e+ ν(e) combined with the form factors for D → K* e+ ν(e) and B → V ℓ+ ℓ- and D → ρ e+ ν(e). Using the entire CLEO-c ψ(3770) → DD event sample, corresponding to an integrated luminosity of 818 pb(-1) and approximately 5.4×10(6) DD events, we measure the form factors for the decays D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e) for the first time and the branching fractions with improved precision. A four-dimensional unbinned maximum likelihood fit determines the form factor ratios to be V(0)/A1(0)=1.48±0.15±0.05 and A2(0)/A1(0)=0.83±0.11±0.04. Assuming Cabibbo-Kobayashi-Maskawa unitarity, the known D meson lifetimes, and our measured branching fractions we obtain the form factor normalizations A1(0), A2(0), and V(0). We also present a measurement of the branching fraction for D+ → ω e+ ν(e) with improved precision.

2.
Phys Rev Lett ; 107(4): 041803, 2011 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-21866994

RESUMEN

Using 586 pb(-1) of e+ e- collision data at E(c.m.) = 4170 MeV, produced at the Cornell Electron Storage Ring collider and collected with the CLEO-c detector, we observe the process e+ e- → π+ π- h(c)(1P). We measure its cross section to be 15.6±2.3±1.9±3.0 pb, where the third error is due to the external uncertainty on the branching fraction of ψ(2S) → π0 h(c)(1P), which we use for normalization. We also find evidence for e+ e- → ηh(c)(1P) at 4170 MeV at the 3σ level and see hints of a rise in the e+ e- → π+ π- h(c)(1P) cross section at 4260 MeV.

3.
J Environ Radioact ; 155-156: 122-129, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26990077

RESUMEN

Simultaneous measurement of tritium and (14)C would provide an added tool for tracing organic compounds through environmental systems and is possible via beta energy spectroscopy of sample-derived methane in internal-source gas proportional counters. Since the mid-1960's atmospheric tritium and (14)C have fallen dramatically as the isotopic injections from aboveground nuclear testing have been diluted into the ocean and biosphere. In this work, the feasibility of simultaneous tritium and (14)C measurements via proportional counters is revisited in light of significant changes in both the atmospheric and biosphere isotopics and the development of new ultra-low-background gas proportional counting capabilities for small samples (roughly 50 cc methane). A Geant4 Monte Carlo model of a Pacific Northwest National Laboratory (PNNL) proportional counter response to tritium and (14)C is used to analyze small samples of two different methane sources to illustrate the range of applicability of contemporary simultaneous measurements and their limitations. Because the two methane sources examined were not sample size limited, we could compare the small-sample measurements performed at PNNL with analysis of larger samples performed at a commercial laboratory. These first results show that the dual-isotope simultaneous measurement is well matched for methane samples that are atmospheric or have an elevated source of tritium (i.e. landfill gas). However, for samples with low/modern tritium isotopics (rainwater), commercial separation and counting is a better fit.


Asunto(s)
Radioisótopos de Carbono/análisis , Metano/análisis , Monitoreo de Radiación/métodos , Tritio/análisis , Gases/análisis , Modelos Teóricos , Instalaciones de Eliminación de Residuos , Purificación del Agua
4.
Genetika ; 21(8): 1403-5, 1985 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-4054619

RESUMEN

A method for ascertaining the mode of current age distributions is suggested for accurate quantitative assessment of some genetic parameters of hereditary diseases, such as age-specific penetrance, frequency of heterozygotes in the general population, fitness. The method is based on estimating the age-specific proportion of affected among the total number of heterozygotes, which seems more reasonable than the common methodology, considering the age-specific proportion of affected among all cases of the disease indicated.


Asunto(s)
Enfermedades Genéticas Congénitas/genética , Factores de Edad , Métodos Epidemiológicos , Tamización de Portadores Genéticos/métodos , Enfermedades Genéticas Congénitas/mortalidad , Genética de Población , Humanos
5.
Genetika ; 20(5): 857-63, 1984 May.
Artículo en Ruso | MEDLINE | ID: mdl-6145659

RESUMEN

The prevalence of hereditary autosomal dominant gastrointestinal adenomatosis in the Moscow population was estimated on the basis of elaboration of an indirect method. This estimate was found to be 1:48000. The prevalence observed is discussed in terms of ascertainment problems and peculiarities of the method of calculation proposed.


Asunto(s)
Neoplasias Gastrointestinales/epidemiología , Neoplasia Endocrina Múltiple/epidemiología , Población Urbana , Adolescente , Adulto , Anciano , Niño , Métodos Epidemiológicos , Neoplasias Gastrointestinales/genética , Humanos , Persona de Mediana Edad , Moscú , Neoplasia Endocrina Múltiple/genética , Sistema de Registros
6.
Genetika ; 21(9): 1567-75, 1985 Sep.
Artículo en Ruso | MEDLINE | ID: mdl-4065562

RESUMEN

Based on the study carried out, we have suggested a populational-genetical model of hereditary polyposes with frequencies of some parameters, such as frequency of mutation, gene's (allele's) frequency, frequency of heterozygotes (general and for separate groups), fertility, fittnes and selection efficiency.


Asunto(s)
Genética de Población , Pólipos Intestinales/genética , Intestino Grueso , Adolescente , Adulto , Anciano , Envejecimiento , Alelos , Niño , Preescolar , Fertilidad , Frecuencia de los Genes , Heterocigoto , Humanos , Lactante , Persona de Mediana Edad , Modelos Genéticos , Moscú , Mutación , Selección Genética
7.
Genetika ; 21(8): 1380-6, 1985 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-3902567

RESUMEN

An attempt has been made to estimate the correlation of oncological illnesses in the families within the limits of segregational and correlational analyses, considering the fact of accumulation in the families of probands with autosomal-dominant polyposes of colon of the cases of primary (without preceding polyposes) colon cancer. Significant correlation was found between the hereditary polyposes and primary colon cancer in the families studied. Based on these data, a hypothesis is discussed of the main gene and its modifications on the phenotypical version in the form of primary benign (polyposes) and malignant (cancer) pathology. No significant correlation was found between colon polyposes and cancer of stomach in the families.


Asunto(s)
Neoplasias Intestinales/genética , Pólipos Intestinales/genética , Intestino Grueso , Técnicas Genéticas , Humanos , Matrimonio , Neoplasias Gástricas/genética
8.
Genetika ; 20(10): 1726-32, 1984 Oct.
Artículo en Ruso | MEDLINE | ID: mdl-6149974

RESUMEN

The effect of parental age on mutation rates of achondroplasia, neurophibromatosis, hereditary gastrointestinal adenomatosis and Duchenne muscular dystrophy loci was studied. A significant parental age effect on the occurrence of new mutations for achondroplasia and neurophybromatosis was shown. The paternal component of this parental age effect was the major factor in the occurrence of such mutations. The risk of the occurrence of new cases of achondroplasia and neurophybromatosis, as compared with their overall frequency, due to new mutations, are increased by a factor of 2 and 3, respectively, up to the paternal age of 50. The possibility of application of the data obtained in genetic counselling is discussed.


Asunto(s)
Frecuencia de los Genes , Enfermedades Genéticas Congénitas/genética , Edad Materna , Mutación , Edad Paterna , Femenino , Humanos , Masculino , Neoplasia Endocrina Múltiple/genética , Distrofias Musculares/genética , Neurofibromatosis 1/genética , Osteocondrodisplasias/genética , Riesgo , Síndrome
9.
Khirurgiia (Mosk) ; (12): 37-41, 1990 Dec.
Artículo en Ruso | MEDLINE | ID: mdl-2079814

RESUMEN

Experiments on dogs demonstrated the role of chronic disorders of duodenal patency (ChDDP) in the development of immediate and late-term postoperative complications of gastric and duodenal ulcer, like incompetence of the duodenal stump, reflux gastritis, progression of duodenostasis existing before the operation, the afferent loop syndrome, postresection cholecystitis and pancreatitis, the dumping syndrome. The formation of valvar anastomoses and early recognition and correction fo ChDDP in resection of the stomach (554 patients) made it possible to reduce significantly both the mortality rates (0.18%) and the percentage of other complications.


Asunto(s)
Síndrome del Asa Aferente/prevención & control , Modelos Animales de Enfermedad , Obstrucción Duodenal/cirugía , Reflujo Duodenogástrico/prevención & control , Gastrectomía/métodos , Úlcera Péptica/cirugía , Síndromes Posgastrectomía/prevención & control , Animales , Enfermedad Crónica , Perros , Obstrucción Duodenal/etiología , Úlcera Péptica/complicaciones , Factores de Tiempo
10.
Khirurgiia (Mosk) ; (3): 17-9, 1995.
Artículo en Ruso | MEDLINE | ID: mdl-7630077

RESUMEN

The work discusses the results of the effect of intraoperative treatment of the abdominal cavity with a magnetite suspension on the T-cell link of the immunological reactivity of the organism of patients with diffuse forms of peritonitis. The preparation intensified lymphocyte proliferative activity. It was found that increase of the lymphocyte stimulation index in intraoperative treatment of the abdominal cavity with magnetite suspension in peritonitis was consequent upon increased production of interleukin-1 and other growth factors by macrophages.


Asunto(s)
Medios de Contraste/administración & dosificación , Hierro/administración & dosificación , Óxidos/administración & dosificación , Peritonitis/terapia , Óxido Ferrosoférrico , Humanos , Interleucina-1/biosíntesis , Macrófagos/inmunología , Peritonitis/inmunología , Peritonitis/cirugía , Suspensiones , Linfocitos T/inmunología
11.
Khirurgiia (Mosk) ; (9): 77-81, 1991 Sep.
Artículo en Ruso | MEDLINE | ID: mdl-1721663

RESUMEN

The blood flow in the portal vein and hepatic artery was studied by means of ultrasonic Doppler flow measurement to investigate organic and regional hemodynamics of the liver in purulent cholangitis. The blood flow in the portal vein was found to be significantly diminished in patients with acute cholangitis and hepatic failure. Hepatic microcirculation was studied on a experimental model of obstructive jaundice and obstructive purulent cholangitis in rats by polarographic measurement of hydrogen clearance. Considerable reduction of the volume rate of the local blood flow was noted, and the degree of the reduction was related to the severity and duration of the disease. Decompression of the biliary tract by external drainage improved the local blood flow rate which, however, diminished again in prolonged external drainage. The use of pharmacological agents for correction of microcirculation in decompression of the biliary tract led to total and rapid correction of the volume rate of the local blood flow.


Asunto(s)
Colangitis/fisiopatología , Circulación Hepática , Enfermedad Aguda , Animales , Aprotinina/uso terapéutico , Ácido Ascórbico/uso terapéutico , Aspirina/uso terapéutico , Colangitis/diagnóstico por imagen , Colangitis/terapia , Colestasis/fisiopatología , Dextranos/uso terapéutico , Dipiridamol/uso terapéutico , Drenaje , Combinación de Medicamentos , Heparina/uso terapéutico , Humanos , Circulación Hepática/efectos de los fármacos , Masculino , Microcirculación , Pentoxifilina/uso terapéutico , Piridinolcarbamato/uso terapéutico , Ratas , Rutina/uso terapéutico , Supuración , Ultrasonografía , Niacinato de Xantinol/uso terapéutico
12.
Vestn Khir Im I I Grek ; 144(2): 24-7, 1990 Feb.
Artículo en Ruso | MEDLINE | ID: mdl-2165672

RESUMEN

Based on an analysis of outcomes of gastric resections for ulcer disease in 825 patients and experimental investigations the authors consider that the main cause of incompetence of the duodenum stump is stagnation of contents in the duodenum. For the prevention of this complications the Billroth-II resection with transverse (valvular) enteroanastomosis is recommended.


Asunto(s)
Obstrucción Duodenal/prevención & control , Duodeno/fisiopatología , Gastrectomía/efectos adversos , Úlcera Péptica/cirugía , Presión/efectos adversos , Dehiscencia de la Herida Operatoria/prevención & control , Animales , Perros , Obstrucción Duodenal/etiología , Gastrectomía/métodos , Humanos , Dehiscencia de la Herida Operatoria/etiología
13.
Vestn Khir Im I I Grek ; 135(8): 29-32, 1985 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-3933159

RESUMEN

The enteral probe feeding was used in 60 patients operated on organs of the abdominal cavity in planned order. The individual nutrition media were composed with special reference to metabolic disorders and the functional state of the gastro-intestinal tract. It helped to make an adequate correction of metabolic disorders and facilitated early normalization of motor activity of the gastro-intestinal tract.


Asunto(s)
Neoplasias Abdominales/cirugía , Colecistitis/cirugía , Nutrición Enteral , Úlcera Péptica/cirugía , Desnutrición Proteico-Calórica/terapia , Proteínas en la Dieta/administración & dosificación , Humanos , Cuidados Posoperatorios/métodos , Hidrolisados de Proteína/administración & dosificación , Almidón/administración & dosificación , Factores de Tiempo
14.
Vestn Khir Im I I Grek ; 142(4): 37-40, 1989 Apr.
Artículo en Ruso | MEDLINE | ID: mdl-2800161

RESUMEN

Experimental investigations gave grounds for the possibility of using the solution of colloid magnetite for the treatment of the abdominal cavity during operation for peritonitis. It was established that the substance has good bacteriocidal and bacteriostatic properties, adsorbs toxic substances present in the peritoneal exudate, is absorbed into blood from the abdominal cavity, does not destruct the cytostructure of the cells of formed elements of the blood, and is easily eliminated from the organism with the bile.


Asunto(s)
Líquido Ascítico/terapia , Hierro/administración & dosificación , Óxidos , Lavado Peritoneal/métodos , Peritonitis/cirugía , Animales , Coloides , Perros , Óxido Ferrosoférrico , Cuidados Intraoperatorios , Ratones , Conejos , Soluciones
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