Development of the Facial Lobe in the Sea Catfish, Plotosus lineatus
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Barbel
Lobe
ABSTRACT 1. The nephridial system of Hirudinaria consists of a series of seventeen pairs of nephridia metamerically arranged in somites VI to XXII. The first six pairs occur in the pretesticular segments (VI-XI), while the remaining eleven pairs lie in the testicular segments (XII-XXII). 2. A typical nephridium consists of the following parts: (i) the initial lobe, (ii) the apical lobe, (iii) the inner lobe, (iv) the main lobe, (v) the vesicle-duct and the vesicle. All the nephridia in the testicular region possess ‘funnels’ (ciliated organs) which are enclosed within the ampullae of the perinephrostomial sinus. There is no continuity or connexion of these ‘funnels’ with the nephridia in the adult leech. 3. The inner end of the initial lobe is directed towards the testis-sac and either ends freely within the connective tissue without coming in contact with the testis-sac, o r is embedded in fibrous tissue in external contact with the wall of the sac, or becomes incorporated within the outer wall of the perinephrostomial sinus. 4. The initial lobe (testis-lobe) forms a very long coiled string of cells round the apical lobe and part of the inner lobe. The inner lobe (the ‘recurrent lobe’ of Bourne) forms a distinct strip of nephridial tissue enclosed between the two limbs of the main lobe besides a small piece which runs alongside the apical lobe. The inner lobe canals serve to connect the intra-cellular canals of all the lobes with one another. 5. The cells of the different lobes of the nephridium are tunnelled through by intra-cellular canals and canaliculi which form a continuous branching network throughout the body of the nephridium. Besides, there is an intra-cellular central canal which makes If ‘rounds’ through the various lobes of the nephridium and opens into the vesicle. The intra-cellular canals and canaliculi open directly or indirectly into the central canal. 6. The vesicle has no muscular layer, and its wall is not contractile. The evacuation of the contents of the vesicle is brought about by the contraction of ventro-Iateral muscles of the bodywall that extend across all the vesicles. The vesicle and the terminal excretory duet do not develop from the rudiments of the true nephridium, but are formed from an ingrowth of the epidermis. 7. A fully developed adult ‘funnel’ (ciliated organ) is a compound structure consisting of (1) a central reservoir and (2) a large number of small independent funnels set on the reservoir and opening into it. The funnels are profusely ciliated. Each funnel is composed of five to six cells, and has the appearance of an ear-lobe with a broad distal and a narrow proximal end. 8. The reservoir is the seat of manufacture of corpuscles which are thrown out of the reservoir through the funnels into the surrounding sinus by the active movements of the cilia of the numerous funnels. 9. The ‘funnel’ is not a degenerate structure. It has, in fact, multiplied into numerous small ciliated funnels, which are much more effective in their ciliary action than a single funnel, even of a large size, could be. Cilia of the funnels show very vigorous movements which keep the fluid in the sinus in constant active circulation. The ciliated organ, instead of serving a renal excretory function, has here become subservient to the sinus-system. 10. The botryoidal vessels are in direct communication with the perinephrostomial sinus. Possibly the corpuscles take up pigment and become the chloragogen cells in the botryoidal vessels. 11. In the embryonic condition the ‘funnel’ is a solid mass of cells which is distinctly continuous with the nephridium by means of a delicate strand of cells. This connexion of the ‘funnel’ with the nephridium snaps later, and the two become discontinuous and discrete structures. In the embryonic solid ciliated organ the funnel-forming cels can be clearly distinguished from the cells of the reservoir. The ‘funnel’ becomes enclosed at an early stage in the perinephrostomial sinus, which is a part of the reduced coelom. 12. The nephridial system of Hirudo is essentially similar to that of Hirudinaria. In Hirudo the initial lobe does not coil round the apical lobe, but forms one mass round the ampullae of the perinephrostomial sinus and another between the apical and main lobes. The inner end of the nephridium is closed as in Hirudinaria. The ‘funnels’ have the same structure and perform the same function as in Hirudinaria.
Lobe
Sinus (botany)
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Dorsal cutaneous innervation of the hand with respect to anatomical landmarks: is there a safe zone?
In this study, we aimed to define the borders of the triangular area between the radial and dorsal nerves on the dorsum of the hand and to determine its dimensions using measurements between anatomic landmarks.We statistically analyzed the relation between the distance from Lister's tubercle to the blending point of the central branches of radial and ulnar nerves and the distance between styloids on 14 hands of seven adult human cadavers (5 males, 2 females). The distances of nerve branches to vertical lines drown distally from both styloid processes were also compared with interstyloid distances to help in presuming the course of these nerves.No statistical constant correlation was determined between the measurements. Neither the height of the triangular area nor the courses of both nerves seemed to be quantitatively related to any measurements between the anatomical landmarks.Variability in these measurements in our study indicates that there is no surgical safe zone on the dorsum of the hand.
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The direct projections of the spinal cord onto the cerebellar cortex were traced using the Nauta method following the placement of cervical or thoracic spinal cord hemisections in six brush-tailed possums. Degenerating fibres reached the cerebellum via typically placed dorsal and ventral spinocerebellar tracts. Although complete differentiation of the terminations of ventral and dorsal tracts was not possible, it was found that the dorsal tract terminates mainly in the ipsilateral anterior lobe vermis and in the pyramis and paraflocculus of the ipsilateral posterior lobe. The ventral tract ends almost entirely in the anterior lobe with the majority of fibres terminating contralateral to the side of the hemisection. Within the anterior lobe, degenerating fibres were distributed fairly symmetrically about the midline in five sagittal rows. Three such rows were found in the posterior lobe. The relatively small number of rows in the anterior lobe (five) may be a characteristic feature of marsupials when compared with eutherian mammals.
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The aim of the research was to study the topography of the liver and to image on computed tomography of the white New Zealand rabbit. We used ten rabbit cadavers. We obtained sagittal frozen cuts. At the level of the plane 10 mm to the left, the left medial lobe was cranial to the left lateral lobe. Caudally were the spleen, the left kidney and parts of the small and large intestines. At the level of the plane 20 mm to the left, the left lateral lobe touched caudally the stomach fundus and body, the papillary process was dorsal to the stomach fundus. At the level of the plane 10 mm to the right, the right lobe was cranially situated to the other lobes. Between the right lobe and caudate lobe were fundus and body of the stomach. Caudate process was caudal to the fundus of the stomach and dorsal to the cranial part of duodenum and ascending colon. It had anatomical contact with the right kidney. Papillary process covered the dorsal part of the stomach. At the level of the plane 20 mm to the right, the right lobe was cranial to the other lobes of the liver. The left medial lobe was covered partially by quadrate lobe. Gall bladder did not reach the ventral border of the liver. The left medial lobe was cranial to the body of the stomach. Caudate lobe touched the muscles of the spine.
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Fundus (uterus)
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Barbel
Lobe
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The chemical composition,energy density and E/P were measured in fresh muscles of darkbarbel catfish Pelteoebagrus vachelli.There was higher crude protein content(15.87%) in darkbarbel catfish than those in yellow catfish Pelteoebagrus fulvidraco,oriental sheatfish Silurus ausotus,southern sheatfish Silurus meridionalis and Leiocassis longirostris,lower than that in large fin long barbel catfish Mystus macropterusand spotted long barbel catfish M.guttatus.The highest crude lipid content(7.55%),energy density and E/P and lowest moisture content(75.71%)were observed in the darkbarbel catfish.The higher crude ash content(1.11%) was found in darkbarbel catfish than that in yellow catfish,lower than that in large fin long barbel catfish and spotted long barbel catfish.Seventeen kinds of amino acids were determined in the muscles,including 7 essential amino acids(Thr,Val,Met,Phe,Ile,Leu and Lys),2 semi-essential amino acids(His,and Arg),and 8 nonessential amino acids(Asp,Glu,Ser,G1y,Ala,Tyr,Cys and Pro).The total amino acids(TAA),total essential amino acids(EAA),total semi-essential amino acids(HEAA),and total nonessential amino acids(NEAA) in dry samples from the farmed stocks were 64.31%,23.95%,6.39%,and 33.97%,respectively.The darkbarbel catfish had higher muscular TAA,EAA,HEAA and NEAA than oriental sheatfish and southern sheatfish did,and lower muscular TAA,EAA,HEAA and NEAA than yellow catfish,large fin long barbel catfish,spotted long barbel catfish and Leiocassis longirostris.The essential amino acids index(EAAI) was 53.92 mg/g and the constitutional rate of the essential amino acids(EAA) met the Food and Agriculture Organization of the United Nations(FAO)/Word Health Organization(WHO) Standard.According to nutrition evaluation,in the amino acids score(AAS) and chemical score(CS),the limited amino acids were Val,Met+Cys and Ile.The total content of 4 taste amino acids was 25.52%,among which Glu,Asp,Gly,Ala was 10.83%,6.22%,4.17%,and 4.30%,respectively,higher than that in oriental sheatfish and southern sheatfish,lower than that in yellow catfish,oriental sheatfish and southern sheatfish.There were 3 saturated fatty acids(SFA),2 mono-unsaturated fatty acids(MUFA) and 4 polyunsaturated fatty acids(PUFA) in the muscle,accounting for 26.53%,28.19%,36.89%in the total fatty aids,respectively.The amount of EPA+DHA,n-3 polyunsaturated fatty acids(n-3 PUFA),n-6 polyunsaturated fatty acids(n-6 PUFA) was 7.11%,7.11%,and 29.78%in fatty acids,respectively.The amount of EPA+ DHA in the muscle was higher than that in yellow catfish and oriental sheatfish.The amount of ω-6PUFA in the muscle was higher than that in yellow catfish and oriental sheatfish.In dry samples,Ca content in the muscle was lower than that in yellow catfish and southern sheatfish;P content was higher than that in yellow catfish and southern sheatfish.The present study revealed that darkbarbel catfish was a high energy fish and had the highest muscular linoleic acid content among the reported freshwater fish.
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Barbel
Hermaphrodite
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The present work was carried out on 50 chick embryo of Dandarawi chicken collected from Assiut University Farm at a 3, 7, 9, 11, 13, 15, 17 and 19 day of prehatching life. At the 3 rd day of incubation, the hepatic diverticulum gave dorsal and ventral parts in relation to the ductus venosus. At the 7th day, the dorsal and ventral parts became the left and right lobes respectively where the gall bladder was located on visceral surface of the right lobe and a transverse fissure dividing the left lobe into dorsal and ventral parts. Also, the vitelline veins caudal to the liver anastomosed together forming the portal vein, which gave off left portal branch to the left lobe of liver and continued as right portal branch to the right lobe. At the 9th day, the right lobe was longer and higher than the left one where the right lobe was in contact dorsally with the mesonephros and the left one was separated from the mesonephros by the glandular stomach. At the 11th day, the interlobar fissure was occupied mainly by the umbilical vein. At the 13th day, the parietal surface of the two lobes was related to the heart and body wall and the gall bladder increased in size and extended laterally. At the 15th day, the cranial end of the right lobe had three processes dorsal, middle and ventral but the cranial end of the left lobe had two processes dorsal and ventral. The duct system of the right lobe was hepatocystic and cystoenteric, but that of the left was hepatoenteric duct.
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Ductus venosus
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Typhlobarbus, gen. nov.Dorsal and anal without osseous spine. Five branched anal rays. Gill-membranes broadly joined to isthmus. Abdomen rounded. No enlarged scales on both sides of anal base. Two pairs of barbels. Lower pharyngeal teeth in two rows. Air-bladder with two divisions, not enclosed in leathery membrane or bony capusle. Lips simple and smooth, adnate to maxillar and mandible respectively. Eostral fold covering part of upper lip, not fringed at its edge and not forminy a preoral chamber. Rostral groove interrupted at the base of maxillary barbel. Upper lip connected with lower one. Postlabial groove short, only laterally developed and extending to mental groove, which is shallow and inconspicuous. Mental region pad-like, without free rim. Lateral line complete, normally decurved, running in middle of caudal peduncle.Typhlobarbus nudiventris, sp. nov.1. Description The body before dorsal fin is slightly depressed and becomes progressively compressed caudad. Mouth is inferior and arched. Thorax-abdomen is flattened. Eostral barbels reach posterior nostrils and maxillary ones extend as far as the vertical from orbit, which is filled by fat globules except a small opening showing the position of extremely regressed eye. At their symphysis, the dentaries are produced into a small knob, but there is no corresponding notch in the upper jaw. The cephalic lateral line appears to be in two series of pores. Grill rakers are triangle-shaped. Anterior back and thorax-abdomen regions are naked.2. Colouration In life the fish was semitransparent with pale pink color. The branchial region was deep red. The fins were colourless except the tail, which was faint gray with a deeper margin. Abdomen was dark gray, the colour of the stomach content showing through the translucent tissues.3. Locality Three specimens were collected in a dark cavern 100 meters vertically deep below the ground surface at an altitude of 1450 meters. The place is called Yangjieba of Jianshui County, in the south part of Yunnan, China.4. Eelationships Based on morphological comparison with genera Iranocypris, Typhlogarra, Caecocypris and Discogobio the authors come to a conclusion on the systematic position of the new genus Typhlobarbus.1) Typhlobarbus belongs to the subfamily Barbinae of Cyprinidae.2) Though Typhlobarbus may have some affinities with Discogobio in consideration of sharing symplesiomorphies, it is impossible for Typhlobarbus and Discogobio to form a sister group for lack of mutual intercalation between symplesiomorphy and synapomorphy.3) So far the authors have been unable to discover any possible relatives below the subfamily level. This is the reason to erect a new genus to place the new species in.
Barbel
Mandible (arthropod mouthpart)
Sternum
Groove (engineering)
Tuft
Peduncle (anatomy)
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Mesenchyme
Lobe
Respiratory tract
Histology
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