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1.
Nature ; 609(7925): 83-88, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36045241

RESUMEN

Classical mechanisms of volcanic eruptions mostly involve pressure buildup and magma ascent towards the surface1. Such processes produce geophysical and geochemical signals that may be detected and interpreted as eruption precursors1-3. On 22 May 2021, Mount Nyiragongo (Democratic Republic of the Congo), an open-vent volcano with a persistent lava lake perched within its summit crater, shook up this interpretation by producing an approximately six-hour-long flank eruption without apparent precursors, followed-rather than preceded-by lateral magma motion into the crust. Here we show that this reversed sequence was most likely initiated by a rupture of the edifice, producing deadly lava flows and triggering a voluminous 25-km-long dyke intrusion. The dyke propagated southwards at very shallow depth (less than 500 m) underneath the cities of Goma (Democratic Republic of the Congo) and Gisenyi (Rwanda), as well as Lake Kivu. This volcanic crisis raises new questions about the mechanisms controlling such eruptions and the possibility of facing substantially more hazardous events, such as effusions within densely urbanized areas, phreato-magmatism or a limnic eruption from the gas-rich Lake Kivu. It also more generally highlights the challenges faced with open-vent volcanoes for monitoring, early detection and risk management when a significant volume of magma is stored close to the surface.

2.
Vet Ther ; 10(4): E1-10, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20425726

RESUMEN

Laboratories use pigmentation, antibiotic susceptibility, and biochemical tests to identify anaerobic organisms that play a role in bovine interdigital necrobacillosis (bovine foot rot). In this study, 16S rRNA gene sequencing was used to identify strains to the species level that were originally classified as Prevotella or Porphyromonas spp by conventional phenotype assessment methods. Of 264 qualified strains from ceftiofur clinical trials, 241 isolates were definitively identified by 16S rRNA sequencing as Porphyromonas levii. Similarly, of 275 qualified strains from tulathromycin clinical trials, 156 isolates were definitively identified by 16S rRNA sequencing as P. levii. The predominance of P. levii in this study supports the role of this organism as an associative agent of bovine foot rot and may have implications for routine laboratory diagnosis.


Asunto(s)
Infecciones por Bacteroidaceae/veterinaria , Enfermedades de los Bovinos/microbiología , Enfermedades del Pie/veterinaria , Porphyromonas/genética , Porphyromonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Animales , Infecciones por Bacteroidaceae/microbiología , Bovinos , Enfermedades del Pie/microbiología
3.
Antimicrob Agents Chemother ; 52(12): 4442-7, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18838596

RESUMEN

TR-701 is the orally active prodrug of TR-700, a novel oxazolidinone that demonstrates four- to eightfold-greater activity than linezolid (LZD) against Staphylococcus and Enterococcus spp. In this study evaluating the in vitro sensitivity of LZD-resistant isolates, TR-700 demonstrated 8- to 16-fold-greater potency than LZD against all strains tested, including methicillin-resistant Staphylococcus aureus (MRSA), strains of MRSA carrying the mobile cfr methyltransferase gene, and vancomycin-resistant enterococci. The MIC(90) for TR-700 against LZD-resistant S. aureus was 2 microg/ml, demonstrating the utility of TR-700 against LZD-resistant strains. A model of TR-700 binding to 23S rRNA suggests that the increased potency of TR-700 is due to additional target site interactions and that TR-700 binding is less reliant on target residues associated with resistance to LZD.


Asunto(s)
Acetamidas/farmacología , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Enterococcus/efectos de los fármacos , Oxazolidinonas/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/química , Antibacterianos/metabolismo , Sitios de Unión , Humanos , Linezolid , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/normas , Modelos Moleculares , Oxazolidinonas/química , Oxazolidinonas/metabolismo , Profármacos/química , Profármacos/farmacología
4.
Hipertens Riesgo Vasc ; 35(2): 64-69, 2018.
Artículo en Español | MEDLINE | ID: mdl-28927871

RESUMEN

INTRODUCTION AND AIM: Metabolic syndrome (MS) comprises a set of risk factors for cardiovascular disease and diabetes. Argentina has numerous epidemiological studies on MS, however, there has been no systematic analysis of the prevalence of MS in our population. To estimate the prevalence of MS in the Argentine Republic, a systematic review of observational studies published during the period 1988-2014 was carried out. SEARCH STRATEGY: A bibliographic search was conducted in the MEDLINE (National Library of Medicine), SciELO (Scientific Electronic Library Online) and LILACS (Latin American and Caribbean Health Sciences Literature) databases on studies conducted in Argentina between January 1989 and December 2014. The following search terms were combined in English, Spanish and Portuguese: 'metabolic syndrome', 'insulin resistance', 'dysmetabolic syndrome', 'prevalence', 'epidemiology', and 'Argentina'. SELECTION OF STUDIES: Epidemiological studies based on the adult population of Argentina with specific report of the prevalence of MS (according to the WHO, ATP III or IDF criteria) were included in the analysis. SYNTHESIS RESULTS: In the initial bibliographic search, 400 publications were identified. In the second phase of search, 296 titles and abstracts were excluded. In the third phase, the full text of 104 studies was analyzed. Finally, 6 publications were included in the analysis that reported the prevalence of MS in a total of 10,191 subjects (39.6% male). The average age of the population was 45.2 years. The prevalence of MS (random effects model) was 27.5% (95% CI: 21.3%-34.1%). The prevalence of MS was higher in men than in women (29.4% vs. 27.4%, respectively, P=.02). In order of frequency, the most common components of MS were dyslipidaemia (38.3%), hypertension (33.4%), obesity (32.1%) and diabetes (7.5%). CONCLUSIONS: Our data show that the prevalence of MS is high, which represents a very important public health problem in Argentina.


Asunto(s)
Síndrome Metabólico/epidemiología , Estudios Observacionales como Asunto , Argentina/epidemiología , Humanos , Resistencia a la Insulina , Morbilidad/tendencias , Vigilancia de la Población , Prevalencia
5.
J Med Chem ; 43(5): 1034-40, 2000 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-10715167

RESUMEN

Through computationally directed broad screening, a novel 1, 5-diphenylpyrazole (DPP) class of HIV-1 nonnucleoside reverse transcriptase inhibitors (NNRTIs) has been discovered. Compound 2 (PNU-32945) was found to have good activity versus wild-type (IC(50) = 2.3 microM) and delavirdine-resistant P236L (IC(50) = 1.1 microM) reverse transcriptase (RT). Also, PNU-32945 has an ED(50) for inhibition of viral replication in cell cultures of 0.1 microM and was shown to be noncytotoxic with a CC(50) > 10 microM. Structure-activity relationship studies on the 3- and 4-positions of PNU-32945 led to interesting selectivity and activity within the class. In particular, the 3-hydroxyethyl-4-ethyl congener 29 is a potent inhibitor of the P236L mutant (IC(50) = 0.65 microM), whereas it is essentially inactive versus the wild-type enzyme (IC(50) > 50 microM). Furthermore, this compound was significantly more active versus the P236L mutant than delavirdine. The synthesis and RT inhibitory activity of various 3- and 4-substituted analogues are discussed.


Asunto(s)
Fármacos Anti-VIH/farmacología , Delavirdina/farmacología , Transcriptasa Inversa del VIH/antagonistas & inhibidores , Pirazoles/síntesis química , Inhibidores de la Transcriptasa Inversa/síntesis química , Farmacorresistencia Microbiana , Transcriptasa Inversa del VIH/genética , Mutación , Pirazoles/química , Pirazoles/farmacología , Inhibidores de la Transcriptasa Inversa/química , Inhibidores de la Transcriptasa Inversa/farmacología , Relación Estructura-Actividad
6.
J Med Chem ; 41(20): 3793-803, 1998 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-9748354

RESUMEN

A series of pyrimidine thioethers was synthesized and evaluated for inhibitory properties against wild-type HIV-1 reverse transcriptase (RT) and an RT carrying the resistance-conferring mutation P236L. Modifications of both the pyrimidine and the functionality attached through the thioether yielded several analogues, which demonstrated activity against both enzyme types, with IC50 values as low as 190 nM against wild-type and 66 nM against P236L RT. Evaluation of a select number of pyrimidine thioethers in cell culture showed that these compounds have excellent activity against HIV-1IIIB-WT and retain good activity against a laboratory-derived HIV-1MF delavirdine-resistant variant.


Asunto(s)
Fármacos Anti-VIH , Delavirdina/farmacología , Transcriptasa Inversa del VIH/antagonistas & inhibidores , Pirimidinas , Inhibidores de la Transcriptasa Inversa , Inhibidores de la Transcriptasa Inversa/síntesis química , Sulfuros , Sustitución de Aminoácidos , Animales , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Línea Celular , Farmacorresistencia Microbiana , Transcriptasa Inversa del VIH/genética , VIH-1/efectos de los fármacos , VIH-1/enzimología , Leucina/genética , Ratones , Prolina/genética , Pirimidinas/síntesis química , Pirimidinas/química , Pirimidinas/farmacología , Inhibidores de la Transcriptasa Inversa/química , Inhibidores de la Transcriptasa Inversa/farmacología , Relación Estructura-Actividad , Sulfuros/síntesis química , Sulfuros/química , Sulfuros/farmacología
7.
Braz J Med Biol Res ; 23(2): 105-11, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2169934

RESUMEN

1. As the first part of a study of pesticide toxicity we report the effects of the solvent dimethylsulfoxide (DMSO) on signal transduction in mutants of Saccharomyces cerevisiae. 2. The enzymes of trehalose metabolism, which are activated and deactivated by a "glucose signal" and by heat shock treatment, were chosen as targets for this study. 3. DMSO was shown to be able to permeate glucose and cAMP. The effects of glucose and cAMP were enhanced by pre-incubating the cells in the presence of DMSO. 4. No effects were observed during the heat shock, suggesting that the solvent acts on the cell membrane. 5. The results suggest that DMSO may be used as a vehicle for small molecules which do not easily penetrate yeast cell membranes, thus providing a new tool for biochemical and toxicological studies.


Asunto(s)
Dimetilsulfóxido/farmacología , Glucosa/metabolismo , Saccharomyces cerevisiae/genética , Transducción de Señal/efectos de los fármacos , Trehalasa/metabolismo , AMP Cíclico/metabolismo , Activación Enzimática/efectos de los fármacos , Calor , Mutación/genética
8.
J Burn Care Rehabil ; 8(6): 558-60, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3436977

RESUMEN

The clinical uses of the air-fluidized Clinitron therapy system and the air suspension KinAir bed are discussed based on a review of 31 patients. The risks of infection and high evaporative water loss on the air-fluidized bed are problems not associated with the air suspension bed. The clinical use of the air suspension bed is much simpler and safer for nursing personnel. The air suspension bed is indicated for patients with massive burn injuries, patients with deep burns of the back, obese burn patients, heavily infected burn patients, and debilitated patients.


Asunto(s)
Lechos , Quemaduras/terapia , Adulto , Unidades de Quemados , Femenino , Humanos
9.
Acta Otolaryngol ; 97(1-2): 105-15, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6689819

RESUMEN

Histological examination of nasal biopsy specimens, rhinoscopical evaluation and nickel analysis in plasma and urine were performed on 59 retired nickel workers. The histological characteristics were graded according to a numerical classification table. Workers with short employment and short retirement time had a significantly lower mean histological scores than those with long employment and long retirement. Thirteen persons (22%) showed epithelial dysplasia, possibly representing precancerous lesions. Also included in the material were four cases of nasal carcinoma. Presence of hyperplastic/polypoid nasal mucosa was inversely related to the duration of retirement, possibly reflecting gradual regression of the mucosal swelling after termination of the irritation. The nickel concentration in plasma and urine was significantly higher among former roasting/smelting workers than in former electrolysis and non-process workers. This is probably a consequence of the slow release of heavy soluble nickel compounds that have accumulated in the organism at the former place of work.


Asunto(s)
Carcinoma de Células Escamosas/patología , Metalurgia , Mucosa Nasal/patología , Níquel/metabolismo , Neoplasias Nasales/patología , Enfermedades Profesionales/patología , Factores de Edad , Anciano , Carcinoma de Células Escamosas/inducido químicamente , Endoscopía , Humanos , Masculino , Persona de Mediana Edad , Níquel/sangre , Níquel/toxicidad , Níquel/orina , Neoplasias Nasales/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Fumar , Factores de Tiempo
10.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1741-1744, set.-out. 2019. tab
Artículo en Inglés | VETINDEX, LILACS | ID: biblio-1038676

RESUMEN

Em seres humanos, a adiponectinemia está associada à obesidade e ao risco aumentado a uma ampla variedade de cânceres. Embora o papel dessa adipocina esteja bem documentado na patogênese do câncer em humanos, tal associação permanece a ser determinada em cães. Nesses animais, a relação da adiponectina com a carcinogênese parece ser ainda meramente especulativa. Nesse contexto, buscou-se nesta investigação comparar os níveis séricos de adiponectina em fêmeas hígidas e em portadoras de carcinomas mamários com diagnóstico histopatológico de carcinoma mamário tubular simples estágio 4, com comprometimento de linfonodos, porém sem metástases a distância detectadas. Foi observado que as cadelas diagnosticadas com carcinoma mamário tiveram níveis séricos de adiponectina significativamente menores (média de 3,72±1,54µg/mL, P<0,05) em relação às fêmeas consideradas hígidas (média de 5,61±2,18µgl/mL), sugerindo associação entre câncer e hipoadiponectinemia similar à encontrada em humanos. Em relação à idade e ao peso corporal dos animais do estudo, não foi encontrada diferença significativa entre os grupos. Os resultados encontrados nas cadelas portadoras de carcinoma mamário do presente estudo corroboram a associação já descrita em humanos entre ocorrência de carcinogênese e baixos níveis de adiponectina.(AU)


Asunto(s)
Animales , Femenino , Perros , Adenocarcinoma/sangre , Adenocarcinoma/veterinaria , Adiponectina , Obesidad/complicaciones , Obesidad/veterinaria
11.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1335-1338, set.-out. 2017. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-879371

RESUMEN

O estresse oxidativo causa peroxidação lipídica e formação de substâncias reativas ao ácido tiobarbitúrico (TBARS), processo que está comprovadamente associado à progressão de neoplasias malignas em seres humanos. Por sua vez, espécies reativas de oxigênio (EROs) são produzidas no processo carcinogênico, de forma que a geração de EROs parece ser, ao mesmo tempo, causa e consequência dele. Em cães, a associação da peroxidação lipídica com a carcinogênese permanece ainda obscura, com estudos escassos, de resultados conflitantes, que, muitas vezes, incluem, dentro de um mesmo grupo amostral, animais portadores de tumores heterogêneos dos pontos de vista morfológico e comportamental, além de estes se apresentarem em estágios bastante distintos. Nesse contexto, buscou-se, na presente investigação, avaliar a concentração plasmática de TBARS em fêmeas hígidas e portadoras de carcinomas mamários com diagnóstico histopatológico de carcinoma mamário tubular simples estágio 4, com comprometimento de linfonodos, porém sem metástases detectadas. Foi observado que as cadelas diagnosticadas com carcinoma mamário tiveram níveis plasmáticos de TBARS significativamente maiores (média de 7,98 ± 1,43µmol/mL, p < 0,0001) em relação às fêmeas consideradas hígidas (média de 6,14 ± 0,53µmol/mL), o que sugere associação entre câncer e maior ocorrência de estresse oxidativo.(AU)


Asunto(s)
Animales , Femenino , Perros , Peroxidación de Lípido , Neoplasias Mamarias Animales/fisiopatología , Estrés Oxidativo , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
12.
Dtsch Med Wochenschr ; 136(9): 417-26; quiz 427-30, 2011 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-21344357

RESUMEN

The calcified aortic stenosis is the dominating valve disease. Patients affected are most common elderly people in the 8 (th) or 9 (th) decade of their life who often show associated comorbidities like reduced left ventricular function, impaired renal function, pulmonary hypertension, and further diseases (Diabetes mellitus, stroke, COPD). In many cases perioperative morbidity and mortality are too high for surgical valve replacement and up to 30 % of patients are rejected. Nevertheless, prognosis of aortic stenosis is worse if the typical symptoms like dyspnea on exertion, syncope, and angina occur. The transcatheter aortic valve implantation is a new method treating this particular group of patients. The aortic valve bioprothesis consists of a balloon-expandable stent or a self-expandable frame, in which a valve of bovine or porcine pericardium is incorporated. The implantation is performed by retrograde access via the femoral or subclavian artery; the balloon-expandable prosthesis can also be implanted by transapical approach. Recently, the PARTNER trial and other studies demonstrate a high implantation success rate and better survival in comparison to standard therapy but exhibit also cerebral vascular and peripheral vascular complications. A further reduction of the available delivery systems and new types of valves which are under experimental tests and clinical evaluation contribute to this development.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Calcinosis/cirugía , Cateterismo Cardíaco/métodos , Procedimientos Endovasculares/métodos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/diagnóstico , Aortografía , Bioprótesis , Calcinosis/diagnóstico , Cateterismo Cardíaco/instrumentación , Cateterismo , Conducta Cooperativa , Disnea/etiología , Ecocardiografía , Ecocardiografía Doppler , Ecocardiografía Transesofágica , Procedimientos Endovasculares/instrumentación , Femenino , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Humanos , Comunicación Interdisciplinaria , Cuidados Paliativos , Complicaciones Posoperatorias/diagnóstico , Diseño de Prótesis
16.
Hipertens. riesgo vasc ; 35(2): 64-69, abr.-jun. 2018. graf, tab
Artículo en Español | IBECS (España) | ID: ibc-172218

RESUMEN

Introducción y objetivo: El síndrome metabólico (SM) comprende un conjunto de factores de riesgo para las enfermedades cardiovasculares y la diabetes. Argentina cuenta con numerosos estudios epidemiológicos sobre SM y, sin embargo, no se ha realizado un análisis sistemático de la prevalencia de SM en nuestra población. Con el fin de estimar la prevalencia de SM en la República Argentina se realizó una revisión sistemática de los estudios observacionales publicados durante el período 1988-2014. Estrategia de búsqueda: Se realizó una búsqueda bibliográfica en las bases de datos MEDLINE (National Library of Medicine), SciELO (Scientific Electronic Library Online) y LILACS (Latin American and Caribbean Health Sciences Literature) sobre estudios realizados en Argentina entre enero de 1988 y diciembre de 2014. Se utilizaron los siguientes términos de búsqueda combinados en los idiomas inglés, castellano y portugués: «síndrome metabólico», «insulinorresistencia», «síndrome dismetabólico», «prevalencia», «epidemiología», «Argentina». Selección de estudios: Fueron incluidos en el análisis los estudios epidemiológicos basados en población adulta de la República Argentina con reporte de la prevalencia de SM (de acuerdo con los criterios de la OMS, ATPIII o IDF). Síntesis de resultados: En la búsqueda bibliográfica inicial se identificaron 400publicaciones. En la segunda fase de búsqueda, 296títulos y resúmenes fueron excluidos. En la tercera fase, se analizó el texto completo de 104estudios. Finalmente, se incluyeron 6 publicaciones en el análisis que reportaron la prevalencia de SM sobre un total de 10.191sujetos (39,6% varones). La edad media de la población fue de 45,2años. La prevalencia de SM (modelo de efectos aleatorios) fue del 27,5% (IC 95%: 21,3-34,1%). La prevalencia de SM fue más elevada en varones que en mujeres (29,4% vs. 27,4%, respectivamente; p=0,02). En orden de frecuencia, los componentes de SM más comunes fueron la dislipidemia (38,3%), la presión arterial elevada (33,4%), la obesidad (32,1%) y la diabetes (7,5%). Conclusiones: Nuestros datos muestran que la prevalencia de SM es alta, lo que representa un problema de salud pública muy importante en Argentina (AU)


Introduction and aim: Metabolic syndrome (MS) comprises a set of risk factors for cardiovascular disease and diabetes. Argentina has numerous epidemiological studies on MS, however, there has been no systematic analysis of the prevalence of MS in our population. To estimate the prevalence of MS in the Argentine Republic, a systematic review of observational studies published during the period 1988-2014 was carried out. Search strategy: A bibliographic search was conducted in the MEDLINE (National Library of Medicine), SciELO (Scientific Electronic Library Online) and LILACS (Latin American and Caribbean Health Sciences Literature) databases on studies conducted in Argentina between January 1989 and December 2014. The following search terms were combined in English, Spanish and Portuguese: 'metabolic syndrome', 'insulin resistance', 'dysmetabolic syndrome', 'prevalence', 'epidemiology', and 'Argentina'. Selection of studies: Epidemiological studies based on the adult population of Argentina with specific report of the prevalence of MS (according to the WHO, ATP III or IDF criteria) were included in the analysis. Synthesis results: In the initial bibliographic search, 400 publications were identified. In the second phase of search, 296 titles and abstracts were excluded. In the third phase, the full text of 104 studies was analyzed. Finally, 6 publications were included in the analysis that reported the prevalence of MS in a total of 10,191 subjects (39.6% male). The average age of the population was 45.2 years. The prevalence of MS (random effects model) was 27.5% (95% CI: 21.3%-34.1%). The prevalence of MS was higher in men than in women (29.4% vs. 27.4%, respectively, P=.02). In order of frequency, the most common components of MS were dyslipidaemia (38.3%), hypertension (33.4%), obesity (32.1%) and diabetes (7.5%). Conclusions: Our data show that the prevalence of MS is high, which represents a very important public health problem in Argentina (AU)


Asunto(s)
Humanos , Masculino , Femenino , Síndrome Metabólico/epidemiología , Diagnóstico Precoz , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Argentina/epidemiología , Indicadores de Morbimortalidad
17.
Arch Tierernahr ; 37(5): 417-27, 1987 May.
Artículo en Alemán | MEDLINE | ID: mdl-3454628

RESUMEN

A total of 1,900 male broilers of the variety White Plymouth Rock was tested with 4 energy concentrations (10.5, 11.5, 12.6 and 13.6 MJ metabolizable energy/kg) and 4 protein concentrations (15.0, 17.5, 20.0 and 22.5% CP) in their first 56 days of life in 16 test groups. The animals were kept in cages and were directly exposed to the natural Cuban summer temperatures from their 15th day of life onwards. As every test group was run with 6 repetitions, the results could be variance analytically calculated. In a comparison of the behaviour of the male animals in winter and in summer it can be stated that the animals took in between 3.4 and 25% more feed in winter than in summer. In general, a lower body protein and body fat amount could be found in all test groups in summer compared to that in winter. Feed expenditure and the utilization of energy and protein were not as good as in winter. It could be shown that both maximum live weight and live weight gain can be achieved in the 2nd fattening period in the Cuban summer if rations containing 12.6 MJ metabolizable energy and 20% CP are fed in a one-phase feeding system.


Asunto(s)
Alimentación Animal , Pollos/metabolismo , Proteínas en la Dieta/metabolismo , Análisis de Varianza , Animales , Composición Corporal , Peso Corporal , Pollos/crecimiento & desarrollo , Cuba , Ingestión de Alimentos , Metabolismo Energético , Lípidos/análisis , Masculino , Proteínas/análisis , Estaciones del Año , Temperatura
18.
Arch Tierernahr ; 37(6): 521-31, 1987 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-3454632

RESUMEN

A total of 1,900 female broilers of the variety White Plymouth Rock was tested with 4 energy concentrations (10.5, 11.5, 12.6 and 13.6 MJ metabolizable energy/kg feed) and 4 protein concentrations (15.0, 17.5, 20.0 and 22.5% CP) in their first 56 days of life in 16 test groups. The animals were kept in cages and were directly exposed to the natural Cuban summer temperatures from their 15th day of life onwards. As every test group was run with 6 repetitions, the results could be variance analytically calculated. In a comparison of male and female broilers in summer one can state that the female animals achieved a lower intake of feed, energy and crude protein as well as a lower live weight than the male animals. In winter the female broilers consumed between 15.7 and 36.4% more feed and achieved a live weight gain between 11.1 and 43% higher than in summer. It could be shown that the maximum live weight of the female broilers could be achieved in summer if rations containing 12.6 MJ metabolizable energy and 20% CP are fed in a one-phase feeding system.


Asunto(s)
Alimentación Animal , Pollos/metabolismo , Proteínas en la Dieta/metabolismo , Análisis de Varianza , Animales , Peso Corporal , Pollos/crecimiento & desarrollo , Cuba , Metabolismo Energético , Femenino , Masculino , Estaciones del Año , Caracteres Sexuales , Temperatura
19.
Arch Tierernahr ; 36(8): 709-29, 1986 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-3789918

RESUMEN

The following values were derived from experimental studies of the crude protein (CP) and amino acid (AA) metabolism of growing fattening bulls, the detailed results of which were described in installments 1-6, for the ascertainment of the content of apparently digestible total protein at the duodenum (ADTPD): a) partial method: Degradation quotaCP = NPN + 0.69 X g pure protein/CP; g AD feed PD = g CP (1 -decomposition quotaCP) X 0.72 or g AD feed PD = 0.31 X g pure protein X 0.72; g ADBPDE = 0.149 X g AD org. matter X 0.80 X 0.72 (ADBPDE = apparently digestible pure bacteria protein at the duodenum, dependent on energy release in the reticulo-rumen; g ADBPDN = g CP X (degradation quotaCP) X 0.80 X 0.72 (ADBPDN = apparently digestible pure bacteria protein at the duodenum, dependent on CP supply of rumen microbes); g AD total PD = g AD feed PD + ADBPDE g AD total PD = g AD feed PD + ADBPDN; b) summarizing method: AD total PD = 0.429 + 10.9 X 0.80/CP in % AD org. matter X (CP intake) X 0.72; AD total PD = 0.196 + 16.6 X 0.80/pure protein % AD org. m. X pure pr. intake X 0.72. The requirement of AD total PD was calculated under consideration of the endogenous urine N, skin N and hair N losses as well as protein retention per kg live weight assuming a utilization of 0.70 for this partial performance. The practical application of this balance method is demonstrated in comparison to the digestible CP-system.


Asunto(s)
Aminoácidos/metabolismo , Alimentación Animal/normas , Bovinos/metabolismo , Proteínas en la Dieta/metabolismo , Duodeno/metabolismo , Animales , Absorción Intestinal , Nitrógeno/metabolismo
20.
Arch Tierernahr ; 29(1): 9-16, 1979 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-464819

RESUMEN

It is to be proved in model experiments with rats that calculations with true digestible amino acids are more exact than calculations with the gross amount of amino acids and therefore are advantageous. 7 resp. 6 rations were tested whose gross contents of lysin, methionine and cystin were balanced. Their content of actually digestible lysin differed, however. The results of the two test series show distinctly that the prediction resp. assessment of the animals' performance in dependence on the amino acid content of the rations is most safely based on the actually digestible amino acids.


Asunto(s)
Aminoácidos/metabolismo , Lisina/metabolismo , Animales , Bioensayo , Peso Corporal , Cistina/análisis , Dieta/normas , Digestión , Análisis de los Alimentos , Lisina/análisis , Metionina/análisis , Ratas
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