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1.
Animal ; 15(2): 100087, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33573963

RESUMEN

Selection of optimal hybrid of Pekin duck and housing system could improve yield and quality of duck meat. The aim of this study was to investigate the effects of two rearing systems (intensive vs semi-intensive housing) on growth performance, carcass quality, and selected physical meat quality traits of two commercial strains of Pekin ducks. The study was performed on 240 one-day-old Pekin ducklings of two different strains (120 ducklings of STAR 53 medium hybrid and 120 ducklings of SM3 heavy hybrid) during a 49-day period. Half the birds (120) were reared in a complete confinement system on a floor (intensive system), while the remaining 120 ducks had access to land outside (semi-intensive system). Growth performance of ducks was determined by BW, weight gain, feed intake, and feed conversion ratio (FCR), carcass quality by dressing percentage, percentage of basic cuts in carcasses, and content of various tissues in basic cuts, while meat quality was determined by pH, drip loss, cooking loss, Warner-Bratzler shear force, and color (L*, a*, and b*) values. At the end of the study, SM3 heavy hybrid and STAR 53 hybrid Pekin ducks achieved similar BWs. Higher final BW and lower overall FCR were found in ducks reared in the intensive system than in ducks kept in the semi-intensive system. Higher dressing percentage, weight and percentage of breast, but also a lower percentage of back with pelvis in the carcasses were determined in SM3 hybrid ducks than in STAR 53 hybrid ducks. The strain of duck did not affect meat pH, drip loss, or L* color value. Moreover, housing system affected the physical meat quality of the ducks, since breasts from ducks reared in the semi-intensive system had higher initial meat pH, higher percentage of EZ-drip loss and cooking loss, and higher L*, a*, and b* values than did breasts from intensively-reared ducks. In conclusion, SM3 ducks were more suited for broiler production due to their better carcass quality than STAR 53 ducks. Furthermore, ducks reared in the intensive system had better growth performance results and better physical meat quality traits than did ducks from the semi-intensive system.


Asunto(s)
Pollos , Patos , Animales , Culinaria , Vivienda para Animales , Carne/análisis
2.
Nat Commun ; 11(1): 3692, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32703946

RESUMEN

Following birth, the neonatal intestine is exposed to maternal and environmental bacteria that successively form a dense and highly dynamic intestinal microbiota. Whereas the effect of exogenous factors has been extensively investigated, endogenous, host-mediated mechanisms have remained largely unexplored. Concomitantly with microbial colonization, the liver undergoes functional transition from a hematopoietic organ to a central organ of metabolic regulation and immune surveillance. The aim of the present study was to analyze the influence of the developing hepatic function and liver metabolism on the early intestinal microbiota. Here, we report on the characterization of the colonization dynamics and liver metabolism in the murine gastrointestinal tract (n = 6-10 per age group) using metabolomic and microbial profiling in combination with multivariate analysis. We observed major age-dependent microbial and metabolic changes and identified bile acids as potent drivers of the early intestinal microbiota maturation. Consistently, oral administration of tauro-cholic acid or ß-tauro-murocholic acid to newborn mice (n = 7-14 per group) accelerated postnatal microbiota maturation.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , Microbioma Gastrointestinal , Administración Oral , Animales , Animales Recién Nacidos , Ácidos y Sales Biliares/administración & dosificación , Absorción Intestinal , Cinética , Lactobacillus/fisiología , Hígado/metabolismo , Metabolómica , Ratones Endogámicos C57BL , Filogenia , Análisis de Componente Principal
3.
Bratisl Lek Listy ; 108(8): 368-70, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18203543

RESUMEN

Follicular dendritic cell sarcoma (FDCS) is a rare tumor, derived from antigen-presenting cells that normally form meshworks in lymphoid follicles. FDCS in general recapitulate the immunophenotypic profile of follicular dendritic cells (FDCs). This tumor affects mainly the lymph nodes, but may arise at a variety of extranodal sites in about one third of cases. We present a case of FDCS in a 52-year-old woman with left neck mass. Histologically, the tumor was composed of oval-to-spindle cells arranged in a fascicular and storiform pattern. Immunohistochemically, the tumor cells were positive for CD21, CD35, and to a lesser extent for EMA and vimentin (Fig. 3, Ref. 14). Full Text (Free, PDF) www.bmj.sk.


Asunto(s)
Sarcoma de Células Dendríticas Foliculares/patología , Neoplasias de Cabeza y Cuello/patología , Ganglios Linfáticos/patología , Femenino , Humanos , Persona de Mediana Edad
5.
J Mol Biol ; 266(3): 479-92, 1997 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-9067605

RESUMEN

We have developed a method for the quantitative, exhaustive sequence specificity determination of DNA-binding proteins. The QuESSD method overcomes the limitations inherent in other published in vitro selection methods, not only defining the consensus sequence, but also quantifying the effect on DNA-protein affinity of replacing each base in the recognition domain with every other base. The features distinguishing this method from other in vitro selection approaches are: (1) instead of synthesizing one target oligonucleotide population containing a long randomized domain, we synthesize several oligonucleotide populations, each randomized at two positions. (2) Instead of carrying out several cycles of selection and amplification, we carry out a single cycle. (3) We have developed data collection and analysis procedures that eliminate artifacts and allow generation of quantitative results. The QuESSD method yields accurate measures of: (a) the selectivity of the protein for each base at each position within the recognition domain (normalized relative selectivity), (b) the contributions of individual sites within the recognition domain to the binding affinity (selectivity variance), (c) the relative binding affinity of any given sequence (global selectivity). We confirmed results by (1) tabulating directly the frequency of appearance of individual species in the pool of protein-bound oligonucleotides by cloning and sequencing individual oligonucleotides, and (2) competition EMSA analysis of oligonucleotides designed on the basis of QuESSD data. We have used this method to map the sequence specificity of the nuclear protein XF1 and to distinguish the sequence specificities of XF1 and the AH receptor complex, both of which bind to XRE1, a xenobiotic responsive element (XRE) located upstream of the CYP1A1 gene. Using data obtained by the QuESSD method, we designed oligonucleotides specific for XF1 or for the AH receptor, and prepared CAT reporter gene constructs carrying these oligonucleotides, or wild-type XRE1, upstream of a minimal promoter. Transfection studies using these constructs indicated that XF1 can function as a weak activator of basal transcription, and can, under some circumstances, compete with the AH receptor for binding to XRE1.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas Nucleares/genética , Factores de Transcripción/genética , Animales , Secuencia de Bases , Sitios de Unión/genética , Línea Celular , Datos de Secuencia Molecular , Mapeo Peptídico , Unión Proteica/genética , Ratas
6.
J Nucl Med ; 39(11): 1951-7, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9829588

RESUMEN

UNLABELLED: During the development and characterization of imaging technology or new imaging protocols, it is usually instructive to perform phantom experiments. Often, very simplified forms of the realistic patient anatomy are used that may be acceptable under certain conditions; however, the implications for patient studies can be misleading. This is particularly true in breast and axillary node imaging. The complexities presented by the anatomy, variable object scatter, attenuation and inhomogeneous distribution of activity in this upper thoracic region provide a significant challenge to the imaging task. METHODS: A tissue-equivalent anthropomorphic phantom of the thorax (Radiology Support Devices, Inc., Long Beach, CA) containing fillable cavities and organs was modified for the studies. The phantom was filled with realistic levels of FDG activity and scanned on a Siemens ECAT HR+ whole-body PET scanner. Breast attachments containing 2.0- and 2.55-cc lesions with lesion-to-background ratios of 5:1 and 7:1, respectively, were imaged. Scatter and attenuation effects were analyzed with various experimental setups. A lymph node experiment and a multibed position whole-phantom scan also were performed to illustrate the extent to which the phantom represents the human thorax. RESULTS: Regions of interest were drawn on the lesions as well as the background breast tissue in all studies. It was found that the signal-to-noise ratio decreased 65% when a more realistic phantom (lesions plus breasts plus thorax, all containing activity) was used, as compared to a simple phantom (lesions plus breasts containing activity; no thorax), due to the effects of increased scatter and attenuation. A 23% decrease in the contrast also was seen from the scan of the more realistic phantom due to surrounding activity from nearby organs such as the heart, as well as an increase in the volume of attenuating media. CONCLUSION: This new phantom allows us to more realistically model the conditions for breast and lymph node imaging, leading to preclinical testing that will produce results that better approximate those that will be found in vivo. The phantom will be a valuable tool in comparing different imaging technologies, data collection strategies and image reconstruction algorithms for applications in breast cancer using PET, SPECT or scintimammography systems.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Fantasmas de Imagen , Tomografía Computarizada de Emisión/instrumentación , Axila , Estudios de Evaluación como Asunto , Femenino , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Modelos Anatómicos , Radiofármacos , Tórax/diagnóstico por imagen
7.
Biochem Pharmacol ; 37(9): 1699-705, 1988 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-2837238

RESUMEN

The fluorescence quenching of acridine orange was used to compare Na+-H+ exchange and ion conductances in renal cortical brush-border membrane vesicles (BBMV) isolated from euthyroid and hyperthyroid rats. In BBMV from euthyroid animals, Na+-H+ exchange was entirely electroneutral. In BBMV from hyperthyroid rats, the total rates of Na+-H+ exchange were about 30% higher than in BBMV from euthyroid animals. However, the electroneutral exchange in these membranes was similar to that in BBMV from euthyroid rats; the observed increase in exchange was due to electrically coupled Na+ and H+ movements through conductive pathways in the membranes. Ion conductances in isolated BBMV were tested with outwardly directed K+ gradients in the presence of carbonyl cyanide m-chlorophenylhydrazone (K+ conductance) or valinomycin (H+ conductance). The K+ conductance was negligible and similar in BBMV from both groups of rats. A significant H+ conductance was present in both kinds of membrane preparations and was by 37% higher in BBMV from hyperthyroid animals. Therefore, our experiments failed to demonstrate an increased electroneutral Na+-H+ exchange in BBMV from hyperthyroid rats. Instead, a finding of a significant electrically BBMV from hyperthyroid rats. Instead, a finding of a significant electrically coupled Na+-H+ antiport in the presence of increased H+ conductance in BBMV from hyperthyroid rats indicates that these membranes may also have increased Na+ conductance.


Asunto(s)
Proteínas Portadoras/metabolismo , Concentración de Iones de Hidrógeno , Hipertiroidismo/metabolismo , Corteza Renal/metabolismo , Sodio/metabolismo , Animales , Transporte Biológico , Técnicas In Vitro , Microvellosidades/metabolismo , Ratas , Intercambiadores de Sodio-Hidrógeno
8.
Med Phys ; 24(3): 369-72, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9089588

RESUMEN

The effects of the mammography film processing replenishment rate on contrast and speed are studied sensitometrically. Two experiments studied decreasing replenishment rates in the Kodak RP developer and quantified changes in the developer by measuring bromide ion concentrations. First, values of NaBr concentration from 1.7 to 8.4 g/L, achieved by reducing the replenishment rate, were tested with sensitometry strips. Second, the developer replenishment rate of a high volume dedicated mammography processor was reduced by one-third, to 20 cm3/1560 cm2, so that the NaBr concentration rose from 2.0 to 12.36. Sensitometric results for four film types and patient films were tested for changes from standard values as NaBr concentration was restored to 3.31 g/L. Fifty-five clinical images obtained at 7.3-9.3 NaBr g/L were compared to their matching previous films, with NaBr levels of 2-3 g/L, for contrast and visibility of the skin line. For the range of the NaBr ion from 1.7 to 7 g/L, no significant sensitometric differences were found. Above 7 g/L, different film types had different sensitometric results. From 7.3 to 9.3 NaBr g/L, 47.5% of the clinical films reviewed by four radiologists had less contrast compared to previous films. Dedicated mammography processors with high film volume (i.e., those that do not have excessive oxidation or foreign dye problems) can operate at lower replenishment rates than are currently employed. All common mammography film types are stable at these lower replenishment rates up to 7.0 NaBr g/L.


Asunto(s)
Mamografía/normas , Fenómenos Biofísicos , Biofisica , Bromuros , Femenino , Humanos , Mamografía/métodos , Control de Calidad , Compuestos de Sodio , Tecnología Radiológica , Película para Rayos X
9.
Int J Radiat Biol ; 54(2): 167-77, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2900274

RESUMEN

The 131I activity was measured in 30 human fetal thyroids in Zagreb district after the Chernobyl accident. A model of radioiodine metabolism in the mother and human fetus which takes into account the age dependence of the uptake and retention of radioiodine in the fetal thyroid was developed. Having assessed that the total intake by the average mother was about 1330 Bq, a good correlation between calculated and measured fetal thyroid activities was found (r = 0.77, P less than 0.001). The fetal thyroid dose reached the maximum of 0.43 micro Gy/Bq intake at about the fifth month of gestation. It was concluded that the risk of having a child with a harmful trait due to 131I absorbed by the mother was negligible.


Asunto(s)
Accidentes , Radioisótopos de Yodo/metabolismo , Intercambio Materno-Fetal , Reactores Nucleares , Dosis de Radiación , Ceniza Radiactiva , Glándula Tiroides/metabolismo , Femenino , Humanos , Embarazo , Ucrania , Yugoslavia
10.
Phys Med Biol ; 33(9): 1065-73, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3057517

RESUMEN

The effect of the intravascular background in the renogram on the calculated renal retention function is known and can be removed. However, the effect of the extravascular background (EVB) has not been thoroughly investigated using patient data. By varying the size of the region of interest containing a single kidney and by deconvolving the 131I-hippuran and 99Tcm-DTPA renograms so generated, the following has been found: (a) the effect of EVB on the mean transit time (MTT) is negligible and EVB subtraction is not necessary, (b) the EVB overestimates the lower relative kidney function (RKF) and underestimates the higher RKF, so that EVB subtraction should be performed if the RKFs are asymmetric. A new method is described in which the correction for EVB is performed following deconvolution. If the RKFs are greater than about 30%, the correction can be performed using a regression equation between the RKFs corrected for EVB and those that are not corrected. When the RKFs are asymmetric to a greater extent, the correction should be performed for each study separately. The proposed method includes a small systematic error due to the inherent limitations of nuclear medicine equipment.


Asunto(s)
Renografía por Radioisótopo/métodos , Adulto , Niño , Humanos , Ácido Yodohipúrico , Compuestos Organometálicos , Ácido Pentético , Pentetato de Tecnecio Tc 99m
11.
Clin Nucl Med ; 24(2): 120-4, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9988072

RESUMEN

In 38 children with proved P-fimbriated Escherichia coli acute pyelonephritis, Tc-99m DTPA dynamic renal scintigraphy in the zoom mode using deconvolution analysis was performed, and the results were compared with those of Tc-99m DMSA scans. From the dynamic study, six functional images of the mean time were generated. Each functional image was analyzed separately to search for focal areas of increased mean time within the kidney contour, especially over the kidney parenchyma. Time-activity curves from these areas were generated and analyzed. Tc-99m DMSA scintigraphy showed generalized or focal decreased uptake in 32 (41.8%) kidneys, and deconvolution analysis of Tc-99m DTPA scintigraphy revealed pathologic renographic curves in 58 (77.6%) kidneys. Prolonged whole-kidney and normal renal parenchymal transit times (dilatation without obstruction) were found in 38 (50%) kidneys, whereas prolonged whole-kidney and renal parenchymal transit times (dilatation with obstruction) were observed in 20 (27.6%) kidneys. Separate analysis of each of the six functional images of the mean time showed focal areas of increased mean time in the kidney parenchyma of 11 kidneys. In five cases, time-activity curves from these areas showed a sharp increase of activity on the descending part of the curve, which might reflect the return of urine from the collecting system into kidney cortex (i.e., intrarenal reflux). These results showed that in a urinary tract with acute pyelonephritis, urodynamic changes may lead to obstructive nephropathy and intrarenal reflux. Tc-99m DTPA renal scintigraphy in the zoom mode using deconvolution analysis with six functional images of the mean time has proved to be a valuable method to evaluate acute pyelonephritis, thus allowing dynamic and morphologic analysis of the urinary tract at the same time.


Asunto(s)
Riñón/diagnóstico por imagen , Pielonefritis/diagnóstico por imagen , Renografía por Radioisótopo , Radiofármacos , Pentetato de Tecnecio Tc 99m , Niño , Preescolar , Infecciones por Escherichia coli/diagnóstico por imagen , Femenino , Cámaras gamma , Humanos , Interpretación de Imagen Asistida por Computador , Lactante , Corteza Renal/diagnóstico por imagen , Masculino , Ácido Dimercaptosuccínico de Tecnecio Tc 99m , Sistema Urinario/diagnóstico por imagen
12.
Neurol Croat ; 41(1-2): 13-20, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1810393

RESUMEN

Cerebral distribution of Tc99m-hexamethylprolenaminoxim (HMPAO) was investigated using single photon emission computerized tomography (SPECT) in 34 patients with primary generalized epilepsy (PGE) during the interictal state. These findings were compared with those in a control group of 9 healthy volunteers. In control subjects uniform selective uptake of HMPAO in cortex, basal ganglia and thalamus was found. In 30 patients (88%) decreased regional perfusion was found as follows: in the cortical region in 6 patients (18%), in the region of the basal ganglia or thalamus in 7 (20%), and in both regions in 17 patients (50%). Four patients had normal SPECT findings. The obtained results permit a hypothesis that the PGE should not be strictly differentiated from the focal epilepsy. A possible explanation of the pathophysiology of PGE has also been discussed.


Asunto(s)
Circulación Cerebrovascular , Epilepsia Generalizada/fisiopatología , Tomografía Computarizada de Emisión de Fotón Único , Adolescente , Adulto , Anciano , Niño , Epilepsia Generalizada/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos de Organotecnecio , Oximas , Exametazima de Tecnecio Tc 99m
19.
Acta Chir Iugosl ; 41(1): 59-62, 1994.
Artículo en Croata | MEDLINE | ID: mdl-7785380

RESUMEN

In the one-year prospective study 71 injured patients were observed (75% male and 25% female). Traffic traumatism was the dominant case (45%). The wounded are divided in the groups with one side fracture of ribs (left/right) and on both sides fracture of ribs considering the side of fracture, and there is consideration about the kind of fracture--there are single fracture of ribs and serial fracture of ribs. The samples of artery blood were followed in PaCO2, %SaO2 and level pH in three points of time: when the patients came, after 24 and after 48 hours. In the group with the both side fracture of the ribs, the fall of worth pH was observed after 48 hours, PaCO2 is increasing to the 6.98 kPa. PaO2 is falling after 48 hours. In %SaO2 there is no considerable difference at any time, but%SaO2 is the highest in the second group. With the serial fracture of ribs wounded are considerate the fall of worth pH which is progressively increasing and is the highest after 48 hours. PaCO2 is increasing in the both groups, but with the serial fracture the worth are considerably higher. PaO2 and %SaO2 are much lower after 48 hours. The authors conclude that the wounded on both sides and wounded with serial fracture along one or several lines of with fracture of all ribs suffer the highest respiratory insufficiency (ARI), so they need artificial ventilation as respiratory support.


Asunto(s)
Insuficiencia Respiratoria/etiología , Fracturas de las Costillas/complicaciones , Adulto , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , Oxígeno/sangre , Estudios Prospectivos , Insuficiencia Respiratoria/sangre , Fracturas de las Costillas/sangre
20.
Acta Chir Iugosl ; 50(4): 109-13, 2003.
Artículo en Sr | MEDLINE | ID: mdl-15307506

RESUMEN

Enteral nutrition can be applicated alone or in combination with parenteral nutrition. Enteral feeding should be applicated as early as possible in preoperative preparation or in postoperative period in respect of contraindications and everyday evaluation of patients. Immunomodulatory substances like arginine, 3-omega-fat acids, ribonucleic acid and glutamine are incorporated in "ready to use" solution for enteral feeding. Enteral feedings oral or via tubes are safe if some precautions are taken: like sitting position and control of feeding tubes position. Use of jejunostomy and promotility agents improved enteral feeding after major abdominal surgery and acute pancreatitis. Enteral feeding and immunonutrition improved postoperative course in reduction of hospital stay, incidence of postoperative complications especially infections. The aim of this review article is to validate pro and con for enteral nutrition in preoperative and postoperative course.


Asunto(s)
Nutrición Enteral , Cuidados Posoperatorios , Nutrición Enteral/efectos adversos , Nutrición Enteral/métodos , Humanos
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