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1.
Meat Sci ; 172: 108309, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33217667

RESUMEN

Effect of various antimicrobial interventions on pork carcass cuts - skin-on and skinless, non-chilled and chilled - was studied. Carcass pieces were inoculated with Salmonella enterica, Shiga toxin-producing Escherichia coli (STEC), Escherichia coli pathogen surrogates or Campylobacter spp. Inoculated pieces were assigned to one of the following antimicrobial treatments: 2.5% and 5.0% room temperature lactic acid, 2.5% and 5.0% warm (55 °C) lactic acid, 400 ppm (0.4 mg/mL) room temperature peroxyacetic acid (PAA) or warm (55 °C) water. Treated pieces were sampled before antimicrobial treatment of non-chilled pork tissue, then at 30 m and 24 h post-treatment. For chilled pork, samples were collected after 24 h chilling and 30 m post-treatment. Lactic acid and PAA treatments reduced (P < 0.05) pathogenic and surrogate bacteria; warm water did not produce similar results. Objective and sensory color evaluations on treated pork indicated minimal negative impacts on pork color. Various antimicrobial interventions were effective in reducing surrogates on pork without diminishing quality.


Asunto(s)
Campylobacter/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Ácido Láctico/farmacología , Ácido Peracético/farmacología , Carne de Cerdo/microbiología , Salmonella enterica/efectos de los fármacos , Escherichia coli Shiga-Toxigénica/efectos de los fármacos , Animales , Antiinfecciosos/farmacología , Color , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Porcinos
2.
Transl Anim Sci ; 2(1): 37-49, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32704688

RESUMEN

To continue the series that began in 1994, the National Beef Quality Audit (NBQA) - 2016 was conducted to quantify the quality status of the market cow and bull beef sector, as well as determine improvements made in the beef and dairy industry since 2007. The NBQA-2016 was conducted from March through December of 2016, and assessed hide-on carcasses (n = 5,278), chilled carcasses (n = 4,285), heads (n = 5,720), and offal items (n = 4,800) in 18 commercial processing facilities throughout the United States. Beef cattle were predominantly black-hided; 68.0% of beef cows and 67.2% of beef bulls possessed a black hide. Holstein was the predominant type of dairy animal observed. Just over half (56.0%) of the cattle surveyed had no mud contamination on the hide, and when mud was present, 34.1% of cattle only had small amounts. Harvest floor assessments found 44.6% of livers, 23.1% of lungs, 22.3% of hearts, 20.0% of viscera, 8.2% of heads, and 5.9% of tongues were condemned. Liver condemnations were most frequently due to abscess presence. In contrast, contamination was the primary reason for condemnation of all other offal items. Of the cow carcasses surveyed, 17.4% carried a fetus at the time of harvest. As expected, mean carcass weight and loin muscle area values observed for bulls were heavier and larger than cows. The marbling scores represented by cull animal carcasses were most frequently slight and traces amounts. Cow carcasses manifested a greater amount of marbling on average than bull carcasses. The predominant fat color score showed all carcasses surveyed had some level of yellow fat. Only 1.3% of carcasses exhibited signs of arthritic joints. Results of the NBQA-2016 indicate there are areas in which the beef and dairy industries have improved and areas that still need attention to prevent value loss in market cows and bulls.

3.
J Anim Sci ; 95(7): 3003-3011, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28727107

RESUMEN

The instrument grading assessment portion of the National Beef Quality Audit (NBQA) - 2016 allows the unique opportunity to evaluate beef carcass traits over the course of a year. One week of instrument grading data was collected each month from 5 beef processing corporations encompassing 18 facilities from January 2016 through December 2016 ( = 4,544,635 carcasses). Mean USDA yield grade (YG) was 3.1 with 1.37 cm fat thickness (FT), 88.9 cm LM area, 393.6 kg HCW, and 2.1% KPH. Frequency distribution of USDA YG was 9.5% YG 1, 34.6% YG 2, 38.8% YG 3, 14.6% YG 4, and 2.5% YG 5. Increases in HCW and FT since the NBQA-2011 were major contributors to differences in mean YG and the (numerically) increased frequency of YG 3, 4, and 5 carcasses found in the current audit. Mean marbling score was Small, and the distribution of USDA quality grades was 4.2% Prime, 71.4% Choice, 21.7% Select, and 2.7% other. Frequency of carcasses grading Prime on Monday (6.43%) was numerically higher than the average frequency of carcasses grading Prime overall (4.2%). Monthly HCW means were 397.6 kg in January, 397.2 kg in February, 396.5 kg in March, 389.3 kg in April, 384.8 kg in May, 385.0 kg in June, 386.1 kg in July, 394.1 kg in August, 399.1 kg in September, 403.9 kg in October, 406.5 kg in November, and 401.9 kg in December. Monthly mean marbling scores were Small in January, Small in February, Small in March, Small in April, Small in May, Small in June, Small in July, Small in August, Small in September, Small in October, Small in November, and Small in December. Both mean HCW and mean marbling score declined in the months of May and June. The month with the greatest numerical frequency of dark cutters was October (0.74%). Comparison of overall data from in-plant carcass and instrument grading assessments revealed close alignment of information, especially for YG (3.1 for in-plant assessment versus 3.1 for instrument grading) and marbling (Small for in-plant assessment versus Small for instrument grading). These findings allow the beef industry access to the greatest volume of beef value-determining characteristics for the U.S. fed steer and heifer population than ever reported, resulting in potentially more precise targeting of future quality and consistency efforts.


Asunto(s)
Bovinos/fisiología , Carne Roja/normas , Animales , Composición Corporal , Bovinos/crecimiento & desarrollo , Femenino , Masculino , Encuestas y Cuestionarios , Estados Unidos
4.
J Anim Sci ; 95(7): 2993-3002, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28727109

RESUMEN

The National Beef Quality Audit (NBQA)-2016 used in-plant cooler assessments to benchmark the current status of the fed steer and heifer beef industry in the United States. In-plant cooler assessments ( = 9,106 carcasses) were conducted at 30 facilities, where approximately 10% of a single day's production were evaluated for USDA quality grade (QG) and yield grade (YG) factors. Frequencies of evaluated traits were 66.5% steer and 33.4% heifer sex classes and 82.9% native, 15.9% dairy-type, and 1.2% estimated breed types. Mean USDA YG factors were 1.42 cm for adjusted fat thickness, 89.5 cm for LM area, 390.3 kg for HCW, and 1.9% for KPH. Mean USDA YG was 3.1, with a frequency distribution of 9.6% YG 1, 36.7% YG 2, 39.2% YG 3, 12.0% YG 4, and 2.5% YG 5. Mean USDA QG traits were Small for marbling score, A for overall maturity, A55 for lean maturity, and A for skeletal maturity. Mean USDA QG was Select with a frequency distribution of QG of 3.8% Prime, 67.3% Choice, 23.2% Select, and 5.6% lower score. Lower score included dark cutter (1.9%), blood splash (0.1%), and hard bone, which are USDA overall maturity scores of C or older (1.8%). Marbling score distributions were 0.85% Slightly Abundant or greater, 7.63% Moderate, 23.54% Modest, 39.63% Small, 23.62% Slight, and 0.83% Traces or less. Carcasses that were Choice or Select and USDA YG 2 or 3 accounted for 70.7% of the carcasses evaluated. Compared with the previous NBQA, we found a numerical increase in mean USDA YG, USDA QG, adjusted fat thickness, HCW, LM area, and marbling score with an increase in dairy-type carcasses and percentage of carcasses grading USDA Prime and Choice as well as frequency of USDA YG 4 and 5. The findings from this study will be used by all segments of the industry to understand and improve the quality of fed steer and heifer beef that is being produced.


Asunto(s)
Bovinos/fisiología , Carne Roja/normas , Animales , Composición Corporal , Cruzamiento , Bovinos/crecimiento & desarrollo , Femenino , Masculino , Encuestas y Cuestionarios , Estados Unidos
5.
Transl Anim Sci ; 1(2): 229-238, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32704647

RESUMEN

The National Beef Quality Audit-2016 (NBQA-2016) was conducted to assess current transportation, mobility, and quality characteristics of U.S. fed steers and heifers. Data were collected at 17 beef processing facilities between March and November 2016. About 8,000 live cattle were evaluated for transportation and mobility, and about 25,000 carcasses were evaluated on the slaughter floor. Cattle were in transit to the slaughter facility for a mean duration of 2.7 h from a mean distance of 218.5 km using trailers with dimensions ranging from 17.84 m2 to 59.09 m2. Area allotted per animal averaged 1.13 m2 and ranged from 0.85 m2 to 2.28 m2. A total of 96.8% of cattle received a mobility score of 1 (walks easily, no apparent lameness). Identification types (35.1% had multiple) were lot visual tags (61.5%), individual tags (55.0%), electronic tags (16.9%), metal-clip tags (9.2%), bar-coded tags (0.05%), wattles (0.01%), and other (2.6%). Cattle were black-hided (57.8%), Holstein (20.4%), red-hided (10.5%), yellow-hided (4.8%), gray-hided (2.9%), brown-hided (1.3%), and white-hided (1.1%). Unbranded hides were observed on 74.3% of cattle; 18.6% had brands located on the butt, 6.3% on the side, and 1.3% on the shoulder (values exceed 100% due to multiple brands). For hide-on carcasses, 37.7% displayed no mud or manure; specific locations for mud or manure were legs (40.8%), belly (33.0%), tail region (15.5%), side (6.8%), and top-line (3.9%). Cattle without horns represented 83.3% of the sample, and cattle that did have horns measured: < 2.54 cm (5.5%), 2.54 to 12.7 cm (8.3%), and > 12.7 cm (2.9%). Carcasses without bruises represented 61.1% of those sampled, whereas 28.2% had 1, 8.2% had 2, 2.1% had 3, and 0.3% had 4 bruises. Of those carcasses with a bruise, the bruise was located on the loin (29.7%), round (27.8%), chuck (16.4%), rib (14.4%), and brisket/plate/flank (11.6%). Frequencies of offal condemnations were livers (30.8%), lungs (18.2%), viscera (16.3%), hearts (11.1%), heads (2.7%), and tongues (2.0%). Compared to NBQA-2011, fewer cattle were identified for traceability, fewer were black-hided, a greater number were Holstein cattle, more with no brand and no horns, fewer without bruises, more liver, lung, and viscera condemnations, and fewer heads and tongues were condemned. The NBQA remains an influential survey for the U.S. beef industry to provide benchmarks and strategic plans for continued improvement of beef quality and consistency.

6.
Transl Anim Sci ; 1(3): 320-332, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32704657

RESUMEN

The National Beef Quality Audit (NBQA) is conducted every 5 yr and was most recently again conducted in 2016. Face-to-face interviews gauged progress in quality associated with live cattle production using procedures first utilized in NBQA 2011. The 2016 NBQA was the first in which interviews concerning fed steers and heifers were combined with an audit of market cow and bull beef. Face-to-face interviews were designed to illicit definitions for beef quality, estimate willingness to pay (WTP) for quality attributes, establish relative importance rankings for important quality factors, and assess images, strengths, weaknesses, potential threats, and shifting trends in the beef industry since the 2011 audit. Individuals making purchasing decisions in 5 market sectors of the steer/heifer and cow/bull beef supply chain were interviewed, including packers (n = 36), retailers (including large and small supermarket companies and warehouse food sales companies; n = 35), food service operators (including quick-serve, full-service, and institutional establishments; n = 29), further processors (n = 64), and peripherally-related government and trade organizations (GTO; n = 30). Face-to-face interviews were conducted between January and November of 2016 using a designed dynamic routing system. Definitions (as described by interviewees) for 7 pre-determined quality factors, including: (1) How and where the cattle were raised, (2) Lean, fat, and bone, (3) Weight and size, (4) Visual characteristics, (5) Food safety, (6) Eating satisfaction, and (7) Cattle genetics were recorded verbatim and categorized into similar responses for analysis. Compared to NBQA-2011, a higher percentage of companies were willing to pay premiums for guaranteed quality attributes, but overall were willing to pay lower average premiums than the companies interviewed in 2011. Food safety had the highest share of preference among all interviewees, generating a double-digit advantage over any other quality factor. The 2 beef industries have an overall positive image among interviewees, and despite lingering weaknesses, product quality continued to be at the forefront of the strengths category for both steer and heifer beef and market cow and bull beef.

7.
Transl Anim Sci ; 1(4): 570-584, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32704679

RESUMEN

The National Beef Quality Audit-2016 marks the fourth iteration in a series assessing the quality of live beef and dairy cows and bulls and their carcass counterparts. The objective was to determine the incidence of producer-related defects, and report cattle and carcass traits associated with producer management. Conducted from March through December of 2016, trailers (n = 154), live animals (n = 5,470), hide-on carcasses (n = 5,278), and hide-off hot carcasses (n = 5,510) were surveyed in 18 commercial packing facilities throughout the United States. Cattle were allowed 2.3 m2 of trailer space on average during transit indicating some haulers are adhering to industry handling guidelines for trailer space requirements. Of the mixed gender loads arriving at processing facilities, cows and bulls were not segregated on 64.4% of the trailers surveyed. When assessed for mobility, the greatest majority of cattle surveyed were sound. Since the inception of the quality audit series, beef cows have shown substantial improvements in muscle. Today over 90.0% of dairy cows are too light muscled. The mean body condition score for beef animals was 4.7 and for dairy cows and bulls was 2.6 and 3.3, respectively. Dairy cattle were lighter muscled, yet fatter than the dairy cattle surveyed in 2007. Of cattle surveyed, most did not have horns, nor any visible live animal defects. Unbranded hides were observed on 77.3% of cattle. Carcass bruising was seen on 64.1% of cow carcasses and 42.9% of bull carcasses. However, over half of all bruises were identified to only be minor in severity. Nearly all cattle (98.4%) were free of visible injection-site lesions. Current results suggest improvements have been made in cattle and meat quality in the cow and bull sector. Furthermore, the results provide guidance for continued educational and research efforts for improving market cow and bull beef quality.

8.
Meat Sci ; 116: 230-5, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26910511

RESUMEN

This study evaluated quality attributes of beef aged as subprimals versus as steaks. Paired subprimals (n=5 pairs of five subprimal types) were selected and assigned to a treatment: (1) aging as vacuum-packaged steaks (portioned 7 d postmortem), or (2) aging as vacuum-packaged subprimals (portioned into steaks after each aging period: ribeye, 28 d; strip loin, 28 d; top sirloin butt, 35 d; tenderloin, 21 d; and short loin, 28 d). To simulate typical U.S. handling and distribution, all steaks were held an additional 14 d before color, shelf life, Warner-Bratzler shear force (WBSF), and consumer sensory analyses were conducted. Aging subprimals tended to result in a lower WBSF for the strip loin and significantly lower WBSF for top sirloin butts. Although consumer panelists preferred the strip loin aged as steaks, they had no preference for aging method for the other muscles. Overall, findings from this study show the potential for portioning subprimals into steaks before aging.


Asunto(s)
Embalaje de Alimentos , Carne Roja/análisis , Animales , Bovinos , Factores de Tiempo , Vacio
9.
J Anim Sci ; 92(12): 5567-82, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25403193

RESUMEN

This experiment tested the hypothesis that reducing the omega-6 (n-6) to omega-3 (n-3) fatty acid (FA) ratio in sow diets will improve performance, characterized by increased litter size, decreased preweaning mortality, and improved growth performance. Second, we determined if the FA profile in sow and piglet blood, colostrum, and milk are altered when sows are fed diets with varied n-6:n-3 ratios and if the dietary FA ratio impacts circulating concentrations of IgG, IgA, eicosapentaenoic (EPA), or docosahexaenoic (DHA) acid. Sows (n=150) were assigned to 1 of 5 treatments (each divided into gestation and lactation diets) on d 80 of gestation. Period 1 (P1) is defined as d 80 of gestation to weaning and Period 2 (P2) refers to the subsequent breeding to weaning. Diets were wheat and barley based (5% crude fat) and treatments consisted of a control (tallow), 3 diets with plant oil-based n-6:n-3 ratios (9:1P, 5:1P, and 1:1P), and a 5:1 fish oil diet (5:1F). Litter size was unaffected by treatment during P1 and P2 (P>0.10). In P1, birth weight was unaffected by diet (P>0.10); however, weaning weight (P=0.019) and ADG from birth to weaning (P=0.011) were greatest for piglets born to 9:1P and 5:1P sows. During P2, 5:1F sows consumed 10% less feed during lactation (P=0.036), tended to have reduced piglet birth weights (P=0.052), and piglet weaning weight was reduced by 0.8 kg (P=0.040) relative to the other diets. Colostrum and piglet serum IgA and IgG concentrations were unaffected by diet (P>0.10). Serum n-3 FA were greatest in sows (P<0.01) consuming 1:1P and 5:1F diets and in their offspring (P=0.014). Serum α-linolenic acid (ALA) was greatest in 1:1P sows and EPA and DHA were greatest in 5:1F sows (P<0.01). In pre-suckle piglet serum, ALA did not differ among treatment groups (P>0.10). Relative to piglets of sows consuming the control diet, EPA was 2.5-fold greater in the 1:1P group and 4-fold greater in 5:1F group (P<0.01) before suckling. In post-suckle samples, ALA was greatest in piglets from the 1:1P sows (P<0.01) and EPA and DHA were greatest in piglets from the 5:1F sows (P<0.01). Feeding diets with plant-based n-6:n-3 ratios of 5:1 or 1:1 did not impact performance relative to a control group but improved the conversion of ALA into EPA and increased the transfer of n-3 to piglets through milk. When a fish-based 5:1 ratio diet was fed, pre-weaning mortality was increased, and piglet birth and weaning weights decreased.


Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Omega-6/farmacología , Ácidos Grasos/análisis , Reproducción/efectos de los fármacos , Sus scrofa/metabolismo , Animales , Calostro/química , Ácidos Grasos/sangre , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-6/administración & dosificación , Femenino , Lactancia/fisiología , Modelos Lineales , Tamaño de la Camada/efectos de los fármacos , Leche/química , Embarazo , Sus scrofa/fisiología , Porcinos , Ácido alfa-Linolénico/sangre
10.
J Anim Sci ; 87(11): 3607-19, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19617510

RESUMEN

Four experiments were conducted to determine the nutritional value of flaxseed meal [FSM; 133 g of ether extract (EE) and 343 g of CP/kg of DM] for swine. In Exp. 1, apparent fecal digestibility (AD) of DM and EE, and the DE and NE contents were determined in growing pigs (n = 32; initial BW, 70 +/- 3 kg) and gestating sows (n = 24; parities, 2 to 4). Diets contained 0, 100, 200, or 300 g of FSM/kg at the expense of wheat, barley, and soybean meal. Fecal samples were collected for 3 d after a 9-d adaptation. The AD for DM and EE were 72.0 +/- 0.4% and 67.4 +/- 4.7%, respectively, for growing pigs and 68.0 +/- 0.5% and 48.9 +/- 1.9% for sows. The DE content was 3.51 and 3.54 Mcal/kg for growing pigs and gestating sows, and NE was estimated to be 2.43 and 2.44 Mcal/kg for growing pigs and sows, respectively. Five ileally cannulated barrows (initial BW, 38 +/- 3 kg) were fed semi-synthetic diets containing 400 g of FSM/kg for a 7-d period (4-d adaptation and 3-d collection) then 7 d of N-free diet to determine basal endogenous N losses in Exp. 2. Standardized ileal digestible AA contents were 29.6 +/- 1.0, 5.7 +/- 0.3, 12.1 +/- 0.8, 16.8 +/- 1.0, 10.3 +/- 0.4, 5.3 +/- 0.3, 14.0 +/- 0.7, 9.4 +/- 0.5, 2.9 +/- 0.2, and 13.8 +/- 0.8 g/kg of dry FSM for Arg, His, Ile, Leu, Lys, Met, Phe, Thr, Trp, and Val, respectively. In Exp. 3, the AD of P and the effects of phytase inclusion on P availability were determined. Five groups of 8 barrows (initial BW, 45 +/- 4 kg) were fed a 300 g of FSM/kg semi-synthetic diet with increasing concentrations of exogenous phytase [0, 575, 1,185, 2,400 and 2,570 phytase units (FTU)/kg]. The AD of P increased from 21 to 61% (P < 0.001). Broken-line analysis estimated the optimal phytase inclusion rate to be 1,415 FTU/kg of diet. Growth performance and carcass fatty acid (FA) profiles of pigs fed FSM were determined in Exp. 4. Two hundred pigs (100 barrows and 100 gilts; initial BW, 32 +/- 4 kg), blocked by sex, were housed in groups of 5 pigs per pen and fed 1 of 4 diets containing 0, 50, 100, or 150 g of FSM/kg. Six market pigs per diet were selected for carcass FA analysis. The ADG, ADFI, and G:F were not affected by dietary FSM (P > 0.05). Increasing FSM in the diet from 0 to 150 g of FSM/kg increased the alpha-linolenic acid content from 11.1 +/- 0.2 to 47.4 +/- 1.2 mg/g of backfat (P < 0.001) and from 5.0 +/- 0.1 to 10.1 +/- 0.6 mg/g of loin tissue (P < 0.001). Flaxseed meal despite its deficiency in lysine can be included up to 150 g/kg of diets for swine and will contribute to the enrichment of the carcass with n-3 fatty acids.


Asunto(s)
Alimentación Animal , Ácidos Grasos/análisis , Lino , Carne/análisis , Semillas , Sus scrofa/metabolismo , Animales , Digestión/fisiología , Lino/química , Humanos , Masculino , Semillas/química , Aumento de Peso/fisiología
12.
South Hosp ; 58(4): 6-7, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-10120399

RESUMEN

With the modern expansion of malpractice insurance among nurses, economic recession and the potential to garnish wages has encouraged attorneys to bring suit against nurses. The cases illustrated stagger the imagination.


Asunto(s)
Responsabilidad Legal , Mala Praxis/legislación & jurisprudencia , Personal de Enfermería en Hospital/legislación & jurisprudencia , Gestión de Riesgos/métodos , Estados Unidos
13.
AJNR Am J Neuroradiol ; 9(2): 237-40, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3128074

RESUMEN

In patients with Parkinson disease, improved visualization of brain iron on a mid-field-strength magnet can be obtained with T2-weighted images and elimination of phase-encoding artifacts. A long echo delay time accentuates the loss of signal from brain iron. However, the long pulse sequence creates phase-encoding artifacts from CSF pulsations at the level of the basal ganglia. These artifacts are eliminated and resolving power increased with additional pulsing in the slice-selective and read gradients. Elimination of motion artifacts enhances visualization of brain iron in three ways: (1) extrapyramidal nuclei containing iron have better definition, (2) abnormalities are better identified, and (3) pseudolesions disappear. Our findings suggest there is significant improvement in the resolving power of brain iron on MR scans made with a mid-field-strength scanner when gradient modification is used.


Asunto(s)
Encéfalo/metabolismo , Hierro/metabolismo , Imagen por Resonancia Magnética/métodos , Enfermedad de Parkinson/diagnóstico , Adulto , Anciano , Humanos , Persona de Mediana Edad
14.
Br J Psychiatry ; 146: 26-31, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2983816

RESUMEN

Nuclear magnetic resonance (NMR) imaging of hydrogen in body water and fat is proving valuable in clinical investigation of the brain. An introduction to the technique and to the biological significance of the images is presented here. The 'multi-parameter' nature of these images is stressed, and the individual parameters described. NMR imaging may well be of value in investigating the pathology of organic and functional psychoses.


Asunto(s)
Espectroscopía de Resonancia Magnética , Encéfalo/metabolismo , Humanos , Espectroscopía de Resonancia Magnética/métodos , Protones , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/metabolismo , Agua/metabolismo
15.
Br J Psychiatry ; 146: 31-5, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2983817

RESUMEN

Proton NMR imaging of the brain is rapidly becoming established as a useful investigative tool in medicine. This paper examines the usefulness of the NMR parameters--spin-lattice relaxation time (T1) and proton density (PD)--in differentiating groups of patients with senile dementia of Alzheimer type (SDAT) and multi-infarct dementia (MID) from each other, and from elderly controls. T1 values increase with severity of dementia. NMR parameters may also be of use in localising regions of brain damage.


Asunto(s)
Demencia/diagnóstico , Espectroscopía de Resonancia Magnética , Anciano , Enfermedad de Alzheimer/diagnóstico , Encéfalo/metabolismo , Demencia/metabolismo , Diagnóstico Diferencial , Humanos , Protones , Agua/metabolismo
16.
Z Gerontol ; 17(3): 136-40, 1984.
Artículo en Alemán | MEDLINE | ID: mdl-6475190

RESUMEN

Spin lattic relaxation times (T1) and proton density derived from proton nuclear magnetic resonance imaging data are measured in elderly patients with senile dementia of Alzheimer type (SDAT) and multi infarct dementia (MID) and the results compared with elderly controls. T1 values of the cerebral white matter are increased in the dementia groups and there is a statistical correlation with severity. Patients with SDAT have significantly differing proton density measures in cerebral white matter from those with MID. The potential value of these results are discussed together with the possible application to identify regional areas of damage.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Demencia/diagnóstico , Espectroscopía de Resonancia Magnética , Anciano , Enfermedad de Alzheimer/psicología , Demencia/psicología , Diagnóstico Diferencial , Humanos , Escala del Estado Mental
17.
J Neurol Neurosurg Psychiatry ; 47(3): 314-6, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6707682

RESUMEN

Nuclear magnetic resonance imaging of the brain will soon be a standard neuroradiological investigation. Previous work has indicated that this is a safe procedure. Tests which measure various aspects of cognition were performed on volunteer subjects before and after (medium and short term) NMR brain imaging and indicate that deterioration did not occur.


Asunto(s)
Encéfalo , Cognición , Espectroscopía de Resonancia Magnética , Adulto , Humanos , Persona de Mediana Edad
20.
Life Sci ; 30(25): 2171-9, 1982 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-7202096

RESUMEN

Rats with large lesions of the superior colliculus do not display the oral stereotypy normally induced by high systemic doses of dopamine-agonists. It has been suggested that collicular lesions have such an effect because they destroy the GABAergic nigrotectal pathway. This suggestion was investigated by observing the effects of bilateral microinjections of the GABA-agonist muscimol into midbrain sites in rats given 8 mg/kg subcutaneous apomorphine. A low dose of muscimol (25 ng in 0.5 ul saline/side) injected into regions of the superior colliculus with nigrotectal innervation almost abolished apomorphine-induced licking and gnawing. Control microinjections of saline into the superior colliculus, or of muscimol into overlying cerebral cortex, were ineffective. This result is consistent with the GABAergic nigrotectal projection being important for the expression of dopamine-related oral stereotypy. It was also found, however, that 25 ng of muscimol suppressed oral stereotypy when microinjected into the mesencephalic reticular formation underlying the superior colliculus. The anatomical basis of this latter effect is uncertain.


Asunto(s)
Apomorfina/farmacología , Mesencéfalo/efectos de los fármacos , Muscimol/farmacología , Oxazoles/farmacología , Conducta Estereotipada/efectos de los fármacos , Colículos Superiores/efectos de los fármacos , Animales , Humanos , Masculino , Muscimol/administración & dosificación , Ratas
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