Electromyographic analysis of the arm muscles in "back support" exercises.

This study aims at quantifying through electromyography the actions of the biceps brachii-BB (long head), triceps brachii-TB (long head) and deltoideus-DA (clavicular portion) muscles, during the going (G) and return (R) phases in "back support" exercises. Surface electrodes were placed at the muscles, according to DELAGI (1981). It was used a specific software and a A/D plate to take the signals. After being collected, the records were processed resulting in efficient values (RMS), were normalized by maximum isometric contraction (MVIC = 100%) and statistically analysed using the Friedman, DSM and Wilcox non-parametric tests. All the muscles presented electromyographic activity of the movements. The triceps brachii was the muscle with higher activity in both phases of the movement. It was concluded that the exercise is indicated for the arm muscle strength development.

Electromyographic analysis of the arm muscles in "front support" exercises.

The electromyographic activity of the biceps brachii--BB (long head), triceps brachii--TB (long head) and deltoideus--DA (clavicular portion) muscles, during the going (G) and return (R) phases in "front support" exercise, as well the efficacy of this exercise for the development of these muscles strength were studied in 10 male volunteers. The values were normalized through maximum voluntary isometric contraction (MVIC = 100%) and statistically analyzed using the Friedman, DMS and Wilcoxon non-parametric test. A value of p < or = 0.05 indicated significance (Campos, 1983). All the muscles presented higher electromyographic activity in the return phase of the movement. The triceps brachii was the muscle which had higher activity in both phases of the movement. It was concluded that the "front support" exercise is efficient for strength development mainly in the triceps brachii muscle.

Electromyographic behaviour of the gastrocnemius muscle during knee extension and flexion performed on the leg press.

The gastrocnemius was analysed in 10 male volunteers during knee flexion and extension with the foot in normal, plantar flexion and dorsal flexion positions. Hewlett-Packard surface electrodes, an electromyographic signal amplifier, a computer equipped with an A/D conversion plaque (Model CAD 10/26), a software specially designed to record and analyse the signals, a horizontal leg press, and electrogoniometers were used. The gastrocnemius muscle showed strong potentials at the end of knee extension and beginning of knee flexion. The muscle presented a similar activity both in the upper and lower platforms. As to bilateral action, the right gastrocnemius presented stronger potentials on the upper platforms, whereas the potentials were bilaterally similar on the lower platforms. As for foot position, the gastrocnemius presented strong potentials when the foot was in plantar flexion. The remaining positions had no effect on the work of the muscle.

Electromyographic evaluation of the rectus femoris muscle during exercises performed on the leg press.

The rectus femoris was analysed in 10 volunteers during knee flexion and extension with the feet in normal, plantar flexion and dorsal flexion positions. Hewlett-Packard surface electrodes, an electromyographic signal amplifier, a computer equipped with an A/D conversion plaque (Model CAD 10/26), software specially designed to record and analyse the signals, Horizontal Leg Press, and electrogoniometers were used. The rectus femoris muscle showed strong potentials at the beginning of knee extension. In the simultaneous bending of the knee and hip the activity was strong toward the end of the movement. The rectus femoris showed a similar activity both in the upper and lower platforms. As for foot positions, the rectus femoris showed the smallest potentials with the foot in plantar flexion and the largest ones with the foot in dorsal flexion.

Ultrastructural study of the lateral lobe of the prostate of Wistar rats submitted to experimental chronic alcohol ingestion.

Alcoholism is considered today one of the most serious social and medical problems. Different investigators have demonstrated that chronic exposure to alcohol causes morphological and physiological changes in the testes and in the accessory sex glands, in the prostate in particular. In the present study, experimental rats were divided into groups receiving sugar cane brandy diluted to 30 degrees G.L. (30%, v/v) and Purina ration ad libitum for 60, 120, 180, 240 and 300 days, respectively. At the end of each period the animals were sacrificed and the lateral lobe of the prostate was collected for histological examination. The results showed atrophied epithelium, accumulation of lipidic droplets and rupture of the microvilli that line the cell surface facing the lumen of cells of the secretory epithelium of the lateral lobe of the prostate.

Electromyographic study of the trapezius muscle in free movements of the shoulder.

The objective of this study is to analyze the simultaneity of the actions of the three portions of the trapezius (superior portion = TS; middle portion = TM and inferior portion = TI) in elevation, lowering, retraction and protraction of the shoulders. The electromyographic tests were carried out in 20 volunteers using a 4-channel TECA TE 2-7 electromyograph and surface and single coaxial needle electrodes. The electromyographs, obtained with the two types of electrodes, show that in elevation and lowering of the shoulders, TS and TM present increasing and decreasing activity, respectively, from the beginning until the end of these movements. In retraction of the shoulders, TM and TI present increasing activity from the beginning to the end of the movement. In protraction, TS, TM and TI do not show any activity.

Electromyographic study of the trapezius muscle in free movements of the arm.

The trapezius muscle (superior, middle and inferior portions) was analyzed in 20 volunteers. The electromyographic tests were carried out using a four-channel TECA TE 2-7 electromyograph with surface- and single coaxial needle electrodes. In abduction, adduction and flexion-extension, the 3 portions show increasing and decreasing activity, respectively, from the beginning until the end of these movements. In hyperextension, the 3 portions show increasing activity from the beginning until the end of the movement, with greater participation of the middle portion. Significant differences were not observed in the electromyographic profile of the trapezius, using surface and needle electrodes.

Fibre types of M. pectineus of the cat (Felis domestica).

As revealed by the NADH-diaphorase, SDH and myosin ATPase, the M. pectineus of the cat possesses at least 3 main kind of fibres, with different distribution on the superficial and deep portions of the muscle. The superficial portion revealed that 23.6% are FOG fibres: 17.8% are SO fibres and 58.6% are FG fibres. Already the deep portion revealed that 61.4% are FOG fibres: 14.5% are SO fibres and 24.1% are FG fibres. The myosin ATPase reaction was used to demonstrate contracting characteristics. These findings suggest that the movements of fast contraction of M. pectineus are predominant.

[Structure of the efferent ductules of the domestic pig (Sus scrofa domestica)]. / Structure des canaux efférents du porc doméstique (sus scrofa domestica).

The ductuli efferentes of the pig have 2 distinct and continuous segments: the proximal or intratesticular segment that is formed in sequence to the labyrinthic portion of the rete testis, on the cranial extremity of the testis, and the distal or epididymal segment that forms the Cani vasculosi or Lobuli epididymidis. The testicular ductuli are more thicker and the epididymal ductuli are more thin, long and flexuous. The last segment is very coiled and forms a bulboid structure that is placed in the head of the epididymis, in which the ductuli jumped into the initial segment of the epididymis. Each efferent duct is formed by a single and cuboidal/columnar epithelium in which are identified three cellular types: ciliated cells, non ciliated cells and intra-epithelial lymphocytes. The epithelial lining rests on a conspicuous basement membrane that is surrounded by collagen fibrils. Among the ductuli is identified a loose connective tissue.

Study of motor units of M. pectineus of the dog (Canis familiaris).

Cross sections of M. pectineus of 6 adult dogs were used to study the number of motor units. Our results revealed that M. pectineus possesses 29,451 muscle fibres and 165 large nerve fibres. Since 60% of these latter fibres are motor fibres, the number of fibres per motor unit of M. pectineus is 294. This fact suggests that this muscle executes finely adjusted movements.

Estudo das vias bilíferas no rato (Rattus Norvegicus): sistematizaçäo do ramo principal esquerdo / Study on biliary passages of the rat (Rattus Norvegicus): systematizing the main left ramus

Utilizando 40 ratos os autores estudaram as vias bilíferas do rato de laboratório, sistematizando o ramo principal esquerdo. Encontraram em 31 ramos do processo papilar, ramos dorsal, dorsomedial, ventro medial e ventral do lobo lateral esquerdo, ramos do lobo medial esquerdo e do quadrado, afluindo para o ramo esquerdo principal. Contribuiçöes dos lobos caudado e direito ocorreram em 9 dissecçöes. Foram encontrados ramos inonimados colaborados na formaçäo do tronco principal

Fibre types of M. pectineus of the dog (Canis familiaris).

As revealed by the NADH-diaphorase, M. pectineus of the dog possesses at least three main kind of fibres: 45.99% of small and slow contracting-red fibres, presenting an intense reaction, specially in the subsarcolemmal region; 45.55% of large and fast contracting-white fibres, presenting a less intense reaction. The remainder 8.46% fibres possess intermediate characteristics. These findings suggest that the movements of slow and fast contraction of M. pectineus are somewhat equilibrated.