The arcuate eminence (AE) is an anatomically consistent bony protrusion located on the upper surface of the petrous bone that has been previously studied as a reference for lateral skull base ...approaches. There is a paucity of information in the neurosurgical literature seeking to improve the safety of the extended middle cranial fossa (MCF) approach using detailed morphometric analysis of the AE.
To evaluate the use of the AE as an anatomical landmark to help with early identification of the internal acoustic canal (IAC) in MCF approaches by means of a cadaveric study, using a new morphometric reference termed the “M-point.”
A total of 40 dry temporal bones and 2 formalin-preserved, latex-injected cadaveric heads were used. The M-point was established as a new anatomic reference by identifying the intersection of a line perpendicular to the alignment of the petrous ridge (PR), originating from the midpoint of the AE, with the PR itself. Subsequent anatomical measurements were performed to measure the distance between M-point and IAC. Additional distances, including PR length and the anteroposterior and lateral AE surfaces, were also measured.
The mean distance between the M-point and the center of the IAC was 14.9 mm (SD ± 2.09), offering a safe drilling area during an MCF approach.
This study provides novel information on identification of a new anatomic reference point known as the M-point that that can be used to improve early surgical identification of the IAC.
Twenty-three thousand four hundred eighty-four beef carcasses were classified according to the Mexican norm NMX-FF-078-SCFI-2002 at the No. 51 Federal Inspected Type abattoir located in the State of ...Tabasco, Mexico, owned by the Beef Cattle Union of Tabasco State. Tabasco State has a Tropical humid (Am) and subhumid (Aw) climate with rains in summer. The study took place between November 2009 and February 2010. The objective of this study was to evaluate independently the influence of each of the grading criteria used for classification on the final quality grade and determine areas for improvement to enhance the quality of Mexican beef carcasses. The beef carcass norm implementation followed a mechanistic approach of the 5 basic evaluation criteria applied in the sequential order: 1) maturity (age), 2) conformation (muscularity), 3) color of the meat, 4) fat color, and 5) distribution of the subcutaneous fat. The quality grades possible were Supreme, Select, Standard, Commercial, Out of Grade, and Veal. The proportion of carcasses classified as Select, Standard, Commercial, Out of Grade, and Veal were 13.4, 45.8, 27.4, 10.6, and 2.7%, respectively. No carcasses had a final quality grade of Supreme. Based on maturity, 79.2% of the carcasses met the specifications for Supreme; however, when the next criterion, conformation, was evaluated only 0.5% of the carcasses met the specifications for Supreme. When carcasses with a criterion grade of Supreme are not included in the analysis, the γ and κ statistics indicated that maturity and conformation have the greatest association and agreement, respectively, with final quality grade. When carcasses with a criterion grade of Supreme are included in the analysis, the κ statistic for the assessment of agreement between final quality grade and criterion indicated a descending order of conformation, subcutaneous fat distribution, maturity, meat color, and fat color. Thus, based on the degree of association and agreement, conformation was identified as the criterion with the greatest influence on final quality grade and the primary reason for the absence of Supreme grading among the carcasses studied. It is concluded that the application of the Mexican beef carcass classification norm NMX-FF-078-SCFI-2002 into a sample population of beef cattle coming out of a tropical beef production environment highlights a system capable of sending animals to slaughter at an early age with adequate meat and fat color and subcutaneous fat distribution although requiring improvement in conformation.
Twenty-three thousand four hundred eighty-four beef carcasses were classified according to the Mexican norm NMX-FF-078-SCFI-2002 at the No. 51 Federal Inspected Type abattoir located in the State of ...Tabasco, Mexico, owned by the Beef Cattle Union of Tabasco State. Tabasco State has a Tropical humid (Am) and subhumid (Aw) climate with rains in summer. The study took place between November 2009 and February 2010. The objective of this study was to evaluate independently the influence of each of the grading criteria used for classification on the final quality grade and determine areas for improvement to enhance the quality of Mexican beef carcasses. The beef carcass norm implementation followed a mechanistic approach of the 5 basic evaluation criteria applied in the sequential order: 1) maturity (age), 2) conformation (muscularity), 3) color of the meat, 4) fat color, and 5) distribution of the subcutaneous fat. The quality grades possible were Supreme, Select, Standard, Commercial, Out of Grade, and Veal. The proportion of carcasses classified as Select, Standard, Commercial, Out of Grade, and Veal were 13.4, 45.8, 27.4, 10.6, and 2.7%, respectively. No carcasses had a final quality grade of Supreme. Based on maturity, 79.2% of the carcasses met the specifications for Supreme; however, when the next criterion, conformation, was evaluated only 0.5% of the carcasses met the specifications for Supreme. When carcasses with a criterion grade of Supreme are not included in the analysis, the γ and κ statistics indicated that maturity and conformation have the greatest association and agreement, respectively, with final quality grade. When carcasses with a criterion grade of Supreme are included in the analysis, the κ statistic for the assessment of agreement between final quality grade and criterion indicated a descending order of conformation, subcutaneous fat distribution, maturity, meat color, and fat color. Thus, based on the degree of association and agreement, conformation was identified as the criterion with the greatest influence on final quality grade and the primary reason for the absence of Supreme grading among the carcasses studied. It is concluded that the application of the Mexican beef carcass classification norm NMX-FF-078-SCFI-2002 into a sample population of beef cattle coming out of a tropical beef production environment highlights a system capable of sending animals to slaughter at an early age with adequate meat and fat color and subcutaneous fat distribution although requiring improvement in conformation. PUBLICATION ABSTRACT
In this study, we show that one single dose of gamma-irradiation at birth induces an inhibition of the cerebellar calcium dependent nitric oxide synthase (NOS) activity, probably correlated to the ...motor abnormalities and the disarrangement in the cerebellar cytoarchitecture observed in adult rats. This decrease in calcium dependent NOS activity could be associated with an increased protein kinase C (PKC) activity. PKC inhibition partially restores calcium dependent NOS activity, indicating that PKC activity could be negatively modulating the catalytic activity of calcium dependent NOS. These findings suggest that a decrease in nitric oxide (NO) production and the related increase in PKC activity could be intracellular events that participate in the onset of motor and cerebellar abnormalities induced by postnatal gamma-irradiation at early stages of life.
En un estudio previo se reportó la factibilidad de utilizar, en condiciones locales, ecuaciones disponibles de predicción de cortabilidad con base en kilogramos (TRC), o expresada como porcentaje de ...la canal (TRYD) de bovino. Todas las ecuaciones consideradas incluyen variables obtenidas en el cuarteo de una media canal, lo que representa una limitante para su adopción en regiones del país (el estado de Jalisco incluido), en donde la evaluación de las canales —previa a su comercialización— se lleva a cabo sin el cuarteo de la media canal. Esta condición marca la necesidad de disponer de ecuaciones de predicción que no se sustenten en variables generadas con el cuarteo de la media canal, lo que se convirtió en el objetivo de esta investigación. Las ecuaciones de predicción propuestas se basan en los datos obtenidos de la fabricación tipo corte español, de treinta canales de toretes cruza indefinida cebú-europeo y menores a 36 meses de edad, procesadas en condiciones comerciales en una carnicería del municipio de Guadalajara, Jalisco, México. El peso de la canal fría mostró una correlación positiva (r=0.98) con el rendimiento de cortes expresados en kilogramos. Un modelo matemático de predicción del peso de los cortes comerciales mostró que la variable de peso de la canal, por sí sola, explicó el 95.60% de la varianza estimada, por lo que se propone como ecuación de predicción bajo estas condiciones.
Nutritive value of ammoniated wheat straw fed to cattle Zorrilla-Rios, J. (Dept. of Agriculture, Bunbury, Western Australia); Horn, G.W; McNew, R.W
Journal of animal science,
(Jan 1991), 1991-Jan, Letnik:
69, Številka:
1
Journal Article
Recenzirano
The effects of ammoniation of wheat straw on site and extent of digestion of nutrients by cattle and the nutritive value of the N added to the straw were studied using eight Hereford steers during ...three consecutive 21-d periods and analyzed in an incomplete block design with steers and periods as orthogonal blocking factors. The steers, approximately 30 mo old and weighing 360 +/- 24 kg, were cannulated in the rumen, duodenum and ileum. Diets consisted of untreated (US) or ammoniated (AS) wheat straw supplemented with a mineral-vitamin mixture. Steers fed US received four supplements in which the percentages of supplemental N from soybean meal (SBM) and urea were 0:100; 33:67; 67:33 or 100:0. Percentage of N and in vitro DM digestibility values were increased in US by the ammoniation process from .42 to 1.82 and 34.8 to 54.3, respectively. Total tract digestibility of OM consumed was similar among treatments, although total tract digestibility of dietary N was decreased by ammoniation. Ammoniation doubled (P less than .05) the synthesis of microbial N per unit of dietary OM truly fermented in the rumen. When SBM and urea were fed in combination they depressed (P less than .10) microbial N flow and synthesis of microbial N per unit of OM truly fermented more than each depressed flow and synthesis individually. The nutritive value of the increased N of AS was equivalent to between 67 and 100% of SBM N based on amounts (g/d) of non-ammonia N apparently digested in the small intestine.