RESUMEN
The aim of the study was to investigate the effect of Bovine Herpesvirus 4 (BoHV-4) and Histophilus (H.) somni on fertility rate of cows in a Hungarian Holstein-Friesian dairy herd with purulent vaginal discharge (PVD). Non-pregnant cows (n = 188) with mature corpus luteum were treated with cloprostenol and 3 days later if they did not show oestrus, were examined by rectal palpation. Animals showing PVD (n = 60/31.9%/) and 14 controls with normal vaginal discharge (Score 0) were randomly selected and further examined by ultrasonography and blood samples were collected for detecting BoHV-4 DNA and transcervical guarded swabs were collected from the uterus for bacteriological examination. Although the majority of the examined animals were infected with BoHV-4 and H. somni including the control animals as well, in group of animals with PVD score 3, fewer animals became pregnant and the duration between the first treatment to pregnancy was significantly extended. Based on these clinical and comparative data, our results confirm that these two microorganisms together may impair important reproductive parameters which may cause large economic losses to dairy farms.
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Enfermedades de los Bovinos/microbiología , Infecciones por Herpesviridae/veterinaria , Herpesvirus Bovino 4 , Infertilidad Femenina/veterinaria , Infecciones por Pasteurellaceae/veterinaria , Pasteurellaceae , Animales , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/virología , Coinfección/veterinaria , Industria Lechera , Endometritis/fisiopatología , Endometritis/veterinaria , Femenino , Infecciones por Herpesviridae/fisiopatología , Hungría , Infertilidad Femenina/microbiología , Infecciones por Pasteurellaceae/fisiopatología , Embarazo , Reproducción , Excreción Vaginal/microbiología , Excreción Vaginal/veterinariaRESUMEN
BACKGROUND: The B-Con Basic 1.0 protocol is a medical training designed to teach how to control massive external haemorrhages in emergency conditions. Spread throughout the United States since 2013, thanks to the Stop the Bleed campaign, it has seen a progressive international spread during 2016-2018. We report here data from the first 18 months of our training in Italy. METHODS: Since January 2017, military Operators enlisted to the Volunteer Military Corps of the Italian Red Cross and registered to the ACS B-Con instructor database have provided B-Con courses. These instructors have provided extensive training, involving learners among military and civilian populations, especially health professionals and students. Further, they have obtained a formal adhesion to the National Stop the Bleed Day 2018. RESULTS: Through August 2018, we trained 1186 learners in Italy on the B-Con protocol. The learners were mainly military personnel and law enforcement agents (620 [52%]) but also students and civilian health personnel (566 [48%]). CONCLUSION: The B-Con protocol has been very well received in Italy by military and police personnel. Good results have been assessed among civilian health professionals and medical students, especially by those operators involved in the field of emergency medicine.
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Medicina de Emergencia/educación , Promoción de la Salud/organización & administración , Hemorragia/prevención & control , Humanos , Italia , Personal Militar/educación , Policia/educaciónRESUMEN
The present study is aimed to test the effectiveness and the reproducibility of the acid pre-treatment of sewage sludge to suppress the methanogenic bacteria activity, in order to increase the hydrogen forming bacteria activity, mainly Clostridium species. The treated sludge has been tested on glucose reach medium under mesophilic conditions (35 degrees C), in batch mode to quantify the biological fermentative hydrogen production. In the whole series of experiments, the main components of biogas are hydrogen (52-60%) and carbon dioxide (40-48%); no methane and hydrogen sulphide were present in it. The rate of biogas production reached a maximum of 75 ml/lh. An overall mean hydrogen conversion efficiency was 11.20% on the assumption of maximum of 3 mol H2/mol glucose. Clostridium spp. multiplied ten times after 10 h of fermentation and over that thousand times at the end of fermentation.
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Anaerobiosis , Clostridium/metabolismo , Hidrógeno/metabolismo , Aguas del Alcantarillado/microbiología , Clostridium/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Cinética , Modelos Biológicos , Oxidación-Reducción , Reproducibilidad de los ResultadosRESUMEN
This paper is aimed to candidate the use of an ISO standard procedure (Guide to the Expression of Uncertainty in Measurement, GUM) for quantitative evaluation of uncertainty in Human Risk estimation under chronic exposure to a hazardous chemical compound. Risk was evaluated by using the usual methodologies: the deterministic reasonable maximum exposure (RME) and the statistical Monte Carlo method; in both cases the procedures to evaluate the uncertainty on risk values are detailed. The paper put in evidence that the procedure is able to single out the variables that contribute mostly to the uncertainty. The obtained results show that the application of GUM procedure is easy and straightforward to estimate the uncertainty value on the results of risk estimation. The procedure is applied to a real case concerning the ingestion of milk contaminated by dioxins in a northern part of Italy; the risk value resulted to be over the minimal threshold of 10(-6) with 20-80% confidence.
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Sustancias Peligrosas/análisis , Sustancias Peligrosas/toxicidad , Modelos Teóricos , Incertidumbre , Animales , Dioxinas/análisis , Dioxinas/toxicidad , Humanos , Leche/química , Método de Montecarlo , Variaciones Dependientes del Observador , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricosAsunto(s)
Anemia Ferropénica/microbiología , Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Adolescente , Anemia Ferropénica/diagnóstico , Anemia Ferropénica/tratamiento farmacológico , Antibacterianos/uso terapéutico , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/aislamiento & purificación , Humanos , Hierro/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Resultado del TratamientoRESUMEN
The validation of the AFM method for elastic modulus E measurement in soft materials (E <5 MPa) is still missing. The interest of measurements in materials with E <5 MPa is mainly biological, including soft tissues and single cells. For the diagnosis of malignant human tumors, a change in cell elasticity, within tissues, has recently been recognized as a marker of metastatic potential. To measure a cell elasticity difference, reproducible E measurements in biological samples are needed. In this work a robust method for a metrological validation of E measurements in the range 500-5000 kPa was developed, based on the realization of thick E standard samples and on the study of the interactions between the measurement process and the sample at micro- and nano-scale. E measurement reproducibility limit of 4% has been reached. This allows designing a very sensitive and reproducible measurement of E in biological samples representing thus a powerful diagnostic tool for cancer detection.
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Dimetilpolisiloxanos , Módulo de Elasticidad/fisiología , Microscopía de Fuerza Atómica/métodos , Elasticidad/fisiología , Humanos , Neoplasias/diagnóstico , Neoplasias/fisiopatología , Reproducibilidad de los ResultadosRESUMEN
OBJECTIVE: To identify risk factors in a nosocomial outbreak of multidrug-resistant Mycobacterium bovis (MDRMB) tuberculosis (TB) among HIV-infected patients. DESIGN: We evaluated the study period (from the first to the last MDRMB smear-positive patients hospitalized in the unit) using a case-control study with three control groups. Since MDRMB is extremely rare, we assumed that a single strain was responsible for all six cases. SETTING: A 19-bed infectious diseases unit in Paris, France. PATIENTS: The index case was an AIDS patient who was hospitalized in September 1989 because of MDRMB TB. The cases were five HIV-infected patients who developed MDRMB TB between January 1990 and October 1991. Controls were randomly selected from HIV-infected patients in our unit during the study period (case-control study 1, 15 patients), during the contact period (at least one MDRMB smear-positive patient hospitalized in the unit; case-control study 2,20 patients), and patients matched according to the length of contact (case-control study 3, 24 patients). INTERVENTIONS: After detecting the nosocomial outbreak, we took respiratory isolation precautions for all patients suspected of having active TB. MAIN OUTCOME MEASURES: Risk factors for MDRMB nosocomial transmission, and the occurrence of new cases of MDRMB infection in HIV-infected patients and health-care workers after the introduction of isolation precautions. RESULTS: The most important predictor of nosocomial transmission of MDRMB to HIV-infected patients was the (mean +/- s.d.) length of contact in days [cases, 22 +/- 15.8; study 1 controls, 11.2 +/- 18.9 (P = 0.07); study 2 controls, 14.6 +/- 8.5 (P = 0.043)]. Only one case of MDRMB TB resulted from exposure to MDRMB-smear-positive patient after the introduction of respiratory isolation measures. The incubation period in the single health-care worker who developed MDRMB TB was longer than in the cases. CONCLUSION: In a nosocomial outbreak of MDRMB TB, the contact time was the main risk factor of transmission to HIV-infected patients. Respiratory isolation measures appear to be effective.
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Infección Hospitalaria/microbiología , Brotes de Enfermedades , Infecciones por VIH/complicaciones , Mycobacterium bovis , Tuberculosis/complicaciones , Adulto , Estudios de Casos y Controles , Farmacorresistencia Microbiana , Femenino , Unidades Hospitalarias , Humanos , Control de Infecciones , Masculino , Persona de Mediana Edad , Mycobacterium bovis/efectos de los fármacos , Paris/epidemiología , Factores de Riesgo , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiologíaRESUMEN
STUDY OBJECTIVES: To evaluate the prognosis of HIV-infected patients admitted to ICUs and to identify factors predictive of short- and long-term survival. DESIGN: A prospective study from January 1, 1990, to December 31, 1992, including all consecutive HIV-infected patients admitted to our ICU for the first time. ICU survivors were followed up until January 1, 1994. SETTING: An 18-bed infectious diseases ICU in a 1,300-bed university hospital in Paris. PATIENTS: Four hundred twenty-one HIV-related admissions were recorded during the study period (33.5% of 1,258 admissions to ICU); 354 HIV-infected patients were first ICU admissions and were analyzed. MEASUREMENTS AND RESULTS: Predictive factors on univariate and multivariate analyses (logistic regression and Cox model) for short- and long-term mortality were performed. Respiratory failure was the main cause of admission (49.2%), followed by neurologic disorders (26.8%), sepsis (10.2%), heart failure (4.5%), and miscellaneous disorders (9.3%). For these groups, in-ICU and in-hospital mortality rates were as follows: 16.7% and 33.9%; 23.2% and 41.1%; 38.9% and 58.3%; 25% and 68.8%; and 12.1% and 24.2%, respectively. In-ICU and in-hospital mortality rates were significantly different across the groups (p=0.026 and 0.002, respectively). Multivariate analysis showed that the in-hospital outcome was significantly associated with functional status (p=0.05), time since AIDS diagnosis (p=0.04), HIV disease stage (0.016), simplified acute physiology score (SAPS I) (p=0.06), need for mechanical ventilation (p<0.000001), and its duration (p=0.0001). In the 281 patients who were discharged alive from the ICU, cumulative survival rates were 51%+/-38% at 6 months, 28%+/-38% at 12 months, and 18%+/-30% at 24 months. Median and crude mean+/-SD survival times were 199 days and 316+/-343 days. Multivariate analysis showed that the long-term outcome was significantly associated with functional status (p=0.000001), weight loss (p=0.00001), the CD4 count (p=0.00001), the HIV disease stage (p=0.01), the duration of AIDS (p=0.001), the admission cause group (p=0.03), and the SAPS I at admission (p=0.00001). CONCLUSIONS: The short-term (in-ICU and in-hospital) outcome of HIV-infected patients was mainly related to the severity of the acute illness (SAPS I, cause of admission, need for and duration of mechanical ventilation), and to the preadmission health status, based on functional status and weight loss. Some of these parameters, in particular the SAPS I and preadmission health status, also influenced the long-term outcome. Whereas HIV-related variables had little impact on the in-ICU outcome, they were closely related with the in-hospital outcome and even more strikingly with the long-term outcome. Thus, the life expectancy of HIV-infected patients, which depends primarily on the natural history of the HIV infection, is the most powerful determinant of the long-term prognosis. Our results confirm that ICU support for HIV-infected patients should not be considered futile.
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Cuidados Críticos , Infecciones por VIH/mortalidad , APACHE , Adulto , Análisis de Varianza , Recuento de Linfocito CD4 , Gasto Cardíaco Bajo/epidemiología , Gasto Cardíaco Bajo/mortalidad , Estudios de Evaluación como Asunto , Estudios de Seguimiento , Predicción , Infecciones por VIH/clasificación , Estado de Salud , Mortalidad Hospitalaria , Humanos , Esperanza de Vida , Modelos Logísticos , Análisis Multivariante , Enfermedades del Sistema Nervioso/epidemiología , Enfermedades del Sistema Nervioso/mortalidad , Paris/epidemiología , Admisión del Paciente/estadística & datos numéricos , Alta del Paciente/estadística & datos numéricos , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Respiración Artificial/estadística & datos numéricos , Insuficiencia Respiratoria/epidemiología , Insuficiencia Respiratoria/mortalidad , Sepsis/epidemiología , Sepsis/mortalidad , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Pérdida de PesoRESUMEN
OBJECTIVE: Comparison of suprasternal Doppler (SST) and thermodilution (TD) for the measurement of cardiac output (CO) in critically ill patients. DESIGN: Prospective study. SETTING: Intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: 65 consecutive critically ill patients requiring a pulmonary artery catheter. INTERVENTIONS: Paired CO measurements were made simultaneously using SST and TD by two independent operators. The time to obtain a CO value by SST was measured. Correlation coefficients and the linear regression equation were determined. A Bland and Altman diagram was plotted. A Bland and Altman diagram was also plotted for the level of cardiac index (CI) values (low: CI < 2.5 l min(-1) m(-2); normal: 2.5 < or = CI < or = 4.5 l min(-1) m(-2); high: CI > 4.5 l min(-1) m(-2)). MEASUREMENTS AND RESULTS: In seven patients SST failed to measure CO. In the remaining 58 patients 314 paired CO measurements were performed. The mean time to measure CO by SST was 73 +/- 45 s. The equation of linear regression was: SST(CO) = 0.84 TD(CO) + 1.39. The correlation coefficient was 0.84. The bias between SST and TD was -0.2 +/- 1.4 l min(-1). Biases were -0.23 +/- 0.50, -0.20 +/- 0.68, and 0.25 +/- 0.92 l min(-1) m(-2) for low, normal, and high levels of CI, respectively. CONCLUSION: SST does not accurately measure CO but allows a rapid assessment of CI level in critically ill patients.
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Gasto Cardíaco , Ecocardiografía Doppler/métodos , Unidades de Cuidados Intensivos , Termodilución , Adulto , Femenino , Hemodinámica , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Pancreatitis/diagnóstico , Cuidados Posoperatorios , Estudios Prospectivos , Choque Séptico/diagnósticoRESUMEN
The interactions between a strain of Saccharomyces cerevisiae and an alginate matrix are investigated to ascertain the main factors affecting the bioreaction evolution. During the tests several parameters (glucose, ethanol, calcium ion and biomass concentration, pH, and alginate bed diameter) were evaluated, coupled with microscopic investigation inside the beads to determine the spatial biomass distribution. A detailed analysis of macro parameters and a correlation among them are proposed using a fuzzy algorithm. A global two-step fuzzy model results in which biomass distribution inside the beads is represented as a hidden parameter.
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Modelos Biológicos , Alginatos/metabolismo , Algoritmos , Biomasa , Biotecnología , Lógica Difusa , Cinética , Saccharomyces cerevisiae/metabolismoRESUMEN
OBJECTIVES: The purpose of this retrospective study was to describe the changes and the effect of Pneumocystis carinii pneumonia (PCP) prophylaxis on induced sputum sensitivity during these five last years METHODS: An induced sputum examination was performed in 80 cases of PCP over a 5-year period. RESULTS: The induced sputum were positive in 30 cases (sensitivity = 37.5%). This sensitivity changed very little during these five years. Thirty of these 80 patients (37.5%) received PCP prophylaxis at least for four weeks before PCP diagnosis. Induced sputum sensitivity was 50% in the group with prophylaxis versus 30% in the group without prophylaxis (p = 0.073). CONCLUSION: In our institution, the induced sputum examination remains an interesting diagnostic procedure for PCP. PCP prophylaxis does not seem to have effects on induced sputum sensitivity.
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Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Líquido del Lavado Bronquioalveolar/microbiología , Neumonía por Pneumocystis/diagnóstico , Esputo/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/complicaciones , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/prevención & control , Aerosoles , Humanos , Pentamidina/uso terapéutico , Neumonía por Pneumocystis/complicaciones , Neumonía por Pneumocystis/microbiología , Neumonía por Pneumocystis/prevención & control , Estudios Retrospectivos , Solución Salina Hipertónica/farmacología , Esputo/efectos de los fármacosRESUMEN
We report a case of spontaneous pneumomediastinum (SPM) in a 3 year-old child, admitted to the emergency department because he presented dyspnea for a few hours, after a paroxysm of cough. The SPM is rare in children; the term "spontaneous" is reserved for cases of pneumomediastinum that haven't a traumatic cause. SPM is seen most commonly in asthmatics and in any patient who induces a Valsalva maneuver. The clinical diagnosis is confirmed by chest radiograph. When the diagnosis is uncertain, the chest CT scan is considered the gold standard of imaging tests, capable of detecting pneumomediastinum even in patients with small amounts of mediastinal air. In this case CT images showed the cause: spontaneous bronchial rupture. The direct sign of bronchial injury is the contiguity of the luminal air with that in the mediastinum. In the literature SPM cases are very rare, at least in health patients without tracheobronchial anomalies. The SPM is generally a benign entity that requires supportive care, and resolution occurs spontaneously, such as in our patient. In this article we want to explain the main clinical, diagnostic and therapeutic aspects of SPM, because, even if it's rare in children, it must be considered in the differential diagnosis of dyspnea; then we want to demonstrate as, in this case, a TC scan was important to identifying the SPM cause: a bronchial rupture.
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Bronquios/lesiones , Enfisema Mediastínico/diagnóstico por imagen , Enfisema Mediastínico/etiología , Antibacterianos/uso terapéutico , Broncodilatadores/uso terapéutico , Preescolar , Diagnóstico Diferencial , Quimioterapia Combinada , Disnea/etiología , Femenino , Glucocorticoides/uso terapéutico , Humanos , Enfisema Mediastínico/complicaciones , Enfisema Mediastínico/terapia , Terapia por Inhalación de Oxígeno , Radiografía Torácica , Rotura Espontánea , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
Scabies is an itchy-parasitic cutaneous infection; it can spread from person to person directly or through clothing, sheets or mattresses. The incidence had fallen a lot during the last ten years, but recently it is growing up again; this is due to immigration of people coming from countries where local hygienic and social conditions are very poor. In this contest it is more frequent to observe the infection in pediatric age, sometimes also newborn. In this particular case the diagnosis can be more difficult because the clinical manifestations are different from pathognomonic lesions we usually see in adult age. We report the clinical case of a newborn, 30-day-old, born in Italy from an Indian family. When the baby was admitted in our department she looked in good physical conditions but she presented a pustular dermatitis all over the body, scalp excluded. The presence in the mother of typical skin lesion and baby's eosinophilia at blood test, induced us to suspect the diagnosis of scabies. However, both the search for acarus at optical microscope on a skin sample obtained with "scarification" and clinical response to a treatment with PAF, were unsuccessful. Moreover, we found in the baby a persistent trombopenia; this fact induced us to think of other hypothesis. Finally the child's positive response to permethrina topical treatment and normalization of the number of platelets let us confirm the initial diagnosis of scabies.
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Escabiosis , Femenino , Humanos , Recién Nacido , Escabiosis/diagnóstico , Escabiosis/tratamiento farmacológicoAsunto(s)
Síndrome de Inmunodeficiencia Adquirida/epidemiología , VIH-1 , VIH-2 , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/virología , Adulto , África/etnología , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , Estudios de Seguimiento , VIH-1/aislamiento & purificación , VIH-2/aislamiento & purificación , Humanos , Masculino , Paris/epidemiología , Estudios Prospectivos , Análisis de SupervivenciaAsunto(s)
Úlcera Péptica Perforada/cirugía , Vagotomía , Adulto , Anciano , Femenino , Gastrectomía , Humanos , Masculino , Persona de Mediana Edad , Vagotomía Gástrica ProximalRESUMEN
The administration of 30 mg/kg of body weight of an alpha-ketoglutarate-pyridoxine complex (alpha-KG compl; stoichiometric ratio alpha-KG: pyridoxine 46.35 to 53.65) to trained non-athletic individuals increases VO2 max by 6% (p less than 0.005). The kinetics of the VO2on- and off-responses at the onset and offset of a rectangular work load is not affected by the drug. Peak blood lactate concentration [Lab] following two supramaximal running work loads lasting 60 s and 132 +/- 4 s, respectively is significantly (p less than 0.05 and p less than 0.005) less after the alpha-KG compl treatment (delta Lab = -1.1 and -2.7 mmol . l-1, respectively) than in a control group. The half time (t1/2) of La disappearance from blood during recovery is unaffected by the alpha-KG compl treatment (19.7 min vs 19.5 min). The increase in VO2 max and the corresponding decrease of [Lab] are not found after separate administration of either of the components of the complex. It is concluded that alpha-KG complex stimulates aerobic metabolism, probably prompting mitochondrial reabsorption of alpha-KG, which activates the malate-oxalacetate shuttle and the generation of high energy phosphates at the substrate level.
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Ácidos Cetoglutáricos/farmacología , Consumo de Oxígeno/efectos de los fármacos , Piridoxina/farmacología , Medicina Deportiva , Adulto , Aerobiosis , Anaerobiosis , Glucólisis/efectos de los fármacos , Semivida , Humanos , Cinética , Lactatos/sangre , Ácido Láctico , Masculino , Factores de TiempoRESUMEN
L-Carnitine (L-C), a well known physiological carrier across the inner mitochondrial membrane of activated long chain fatty acids and acceptor of acyl groups from acyl-CoA, has been recently synthesised industrially. This has made it possible to study the effects of L-C loading (4 g X d(-1) by mouth over a period of 2 weeks) on the aerobic and anaerobic performance of 6 long distance competitive walkers. As a result of the treatment: 1) mean total, free and esterified serum L-C both at rest and shortly after completing a 120 min walk at about 65% of the individual maximal aerobic power (VO2max) were significantly increased; 2) VO2max increased 6%, from 54.5 +/- 3.7 (S.D.) to 57.8 +/- 4.7 m1O2 X kg(-1) X min(-1) (P less than 0.02); 3) blood lactate concentration (Lab) as a consequence of short bouts repeated exercise (series of 10, 15 and 20 jumps off both feet on a force platform) was unchanged; 4) heart rate, pulmonary ventilation, oxygen consumption, and respiratory quotient in the same conditions as for 1) were unchanged. It is concluded that, in trained athletes, as a consequence of L-C loading VO2max is slightly but significantly raised, probably as a result of an activation of substrate flow through the TCA cycle, whereas the lipid contribution to metabolism in prolonged submaximal exercise remains unchanged.
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Carnitina , Resistencia Física , Adolescente , Adulto , Aerobiosis , Anaerobiosis , Análisis de los Gases de la Sangre , Humanos , Persona de Mediana Edad , Intercambio Gaseoso PulmonarRESUMEN
Quinacrine complexes with native DNA (Calf thymus, Micrococcus lysodeikticus, Escherichia coli, Bacillus subtilis, and Colstridium perfringens) and synthetic polynucleotides (poly(dA) . poly(dT), poly[d(A-T)] . poly[d(A-T)], poly(dG) . poly(dC) and poly[d(G-C)] . poly[d(G-C)]) has been investigated in solution at 0.1 M NaCl, 0.05 M Tris HCl, 0.001 M EDTA, pH 7.5, at 20 degrees C. Fluorescence excitation spectra of complexes with dye concentration D = 5-30 microM and DNA phosphate concentration P = 400 microM have been examined from 300 to 500 nm, while collecting the emission above 520 nm. The amounts of free and bound quinacrine in the dye-DNA complexes have been determined by means of equilibrium dialysis experiments. Different affinities have been found for the various DNAs and their values have been examined with a model that assumes that the binding constants associated with alternating purine and pyrimidine sequences are larger than those relative to nonalternating ones. Among the alternating nearest neighbor base sequences, the Pyr(3'-5')Pur sequences, i.e., C-G, T-G, C-A and T-A seem to bind quinacrine stronger than the remaining sequences. In particular the three sites, where a G . C base pair is involved, are found to display higher affinities. Good agreement is found with recent calculations on the energetics of intercalation sites in DNA. The analysis of the equilibrium shows also that the strength of the excitation spectrum of bound dye depends strongly upon the ratio of bound quinacrine to DNA. This effect can be attributed to dye-dye energy transfer along DNA.
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ADN/análisis , Quinacrina/análisis , Animales , Sitios de Unión , Bovinos , ADN Bacteriano/análisis , Polinucleótidos/análisis , Espectrometría de Fluorescencia , Timo/metabolismoRESUMEN
The article verifies health's state and style of life of the goldsmith people of the USSL n. 71-Valenza Po. The study, executed in the 1989 year, consisted in the distribution of a autowriting questionnaire to 565 goldsmith who are working for the majority in small factory. Questionnaire's analysis showed the young age of workers and the big experience in specific duty. The diseases of locomotor district are represented with great differences respect data of italian population. These data are plausibility induced with the postural vices during working activity. Other pathologies relevant are contact dermatitis, chronic bronchitis, bronchial asthma and optic disturb. The results of the study had induced the Authors to organize new and over deepened epidemiological studies to investigate disturbs of visus and locomotor district.