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1.
Two specimens of a group of five foetuses, 35–37 mm in total length, of Squalus acanthias were serially sectioned and stained. These specimens were studied for the purpose of testing statements made in the literature, especially by Holmgren ('40), regarding cell sources and skeletal development. Many of Holmgren's results were confirmed with some important differences in detail. Limited blastemas of dermal bones were not evident although a diffuse subepidermal blastema was present in certain areas. There is evidence of delamination addition to the jaws and many parts of the endocranium. Although the trabecula is in part of visceral origin, the visceral material does not represent an infrapharyngohyal since it always has been an integral part of the endocranium, never a formed element of the arch. The same applies to the pharyngo region of the hyoid arch. The pharyngohyal tissue forms the area of articulation of the hyomandibula and the lamina hypotica. Thus a typical lateral commissure is not formed and the resulting otic capsule-basicranial association is unique to the elasmobranchs. The hyomandibula is the epihyal and there is no evidence of a symplectic in this group. The jaws appear to incorporate delamination tissue, associated in teleostomes with dermal bone, in addition to the neural crest proper.  相似文献   

2.
To show the relationships of calcium accumulation in the thoracic aorta to the other tissues, calcium contents were determined with a microwave-induced plasma-atomic emission spectrometer on arteries, veins, cartilages, ligaments, and bones. These tissues were resected from 18 individuals, consisting of 11 men and 7 women who died in the age range 59–91 yr. As thoracic and abdominal aortas are routinely used for radiographic examination of arterial calcification, they appear to be standard tissues of the calcium accumulation. The calcium accumulations were determined in the femoral artery, the superior and inferior venae cavae, the internal jugular vein, cartilages of the articular disk of the temporomandibular joint and the intervertebral disk, both the ligaments of the anterior cruciate ligament and the ligamentum capitis femoris, and the calcaneus, in contrast with the thoracic aorta. As calcium increased in the thoracic aorta, it increased in the femoral artery, the articular disk of the temporomandibular joint, the intervertebral disk, both ligaments of the anterior cruciate ligament, and the ligamentum capitis femoris, but it did not increase in veins, such as the superior and inferior venae cavae and the internal jugular vein. In contrast, it decreased in the calcaneus.  相似文献   

3.
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5.
《Journal of Zoology》1969,159(1):97-129
In Polyptems senegalus a peculiar venous system exists. The pattern is symmetrical in embryos and in early-larval stages, but soon the asymmetrical development of the Cuvierian ducts, originating from vitelline veins, causes a predominance of the system to the right side. The two posterior cardinal veins coalesce except in the anterior region, where the right vein becomes the direct continuation of the single vein; in later stages the single posterior cardinal vein acquires a peculiar disposition, partially in the left and partially in the right kidney. The inferior jugular veins become asymmetrical as well. The anterior cardinal veins are replaced by lateral cephalic veins. A special vein in the abdomen may be considered as being a vena cava. Other peculiar items are the pulmonary veins. Other veins are more or less similar to those of other fishes.  相似文献   

6.
目的:探讨三维动态增强磁共振血管成像(30 DCE MRA)对于颈部静脉系统疾病的临床应用价值。方法:对7例疑有颈部静脉病变的病人进行了3D DCE MRA检查,观察对病变血管及正常血管显示情况。结果:7例检查图像都能清晰显示正常血管结构及病变情况。其中2例正常,2例颈静脉血栓,1例颈静脉癌栓,1例颈静脉扩张,2例动静脉瘘。所有病例均经手术及(或)DSA证实。结论:3D DCE MRA是一种简便,易行,有效的血管检查方法,分辨率高,假阳性率低,在临床上已广泛应用,但临床上多限于动脉系统疾病的诊断。只要选择合适的序列、扫描时间及对比剂的剂量就能较好显示静脉血管情况。此项技术的应用,在颈部静脉病变诊断中有很大的实用价值。  相似文献   

7.
To elucidate age-related changes of mineral contents in human veins, the relative contents (RCs) of elements in the human internal jugular veins, superior and inferior venae cavae, and femoral veins from 27 subjects ranging from 40 to 98 yr old were analyzed by inductively coupled plasma atomic emission spectrometry. The average RCs of calcium in the 27 specimens were the highest in the internal jugular vein, followed in descending order by the superior vena cava, femoral vein, and inferior vena cava. The RCs of calcium and phosphorus in the internal jugular veins started to increase after the age of 50 yr, became the highest in subjects in their 60s and thereafter decreased gradually. It is noted that such accumulations of minerals, similar to the internal jugular vein, were also found in the veins, such as the superior and inferior venae cavae, and femoral vein. Accumulation of minerals in the veins is different from that of arteries, which increase progressively by aging, but do not decrease.  相似文献   

8.
The morphometry, histochemistry, and biomechanical relationships of rectus capitis muscles were examined in adult cats. This family of muscles contained six members on the dorsal, ventral, and lateral aspects of the upper cervical vertebral column. Three dorsal muscles (rectus capitis posterior major, medius, and minor) formed a layered complex spanning from C1 and C2 to the skull. Rectus capitis posterior major was composed predominantly of fast fibers, but the other two deeper muscles contained progressively higher proportions of slow fibers. One ventral muscle, rectus capitis anterior major, was architecturally complex. It originated from several cervical vertebrae and appeared to be divided into two different heads. In contrast, rectus capitis anterior minor and rectus capitis lateralis were short, parallel-fibered muscles spanning between the skull and C1. The ventral muscles all had nonuniform distributions of muscle-fiber types in which fast fibers predominated. Dorsal and ventral muscle groupings usually had cross-sectional areas of 0.5 cm2 or more, reflecting a potential capacity to generate maximal tetanic force in excess of 9 N. Biomechanical analyses suggested that one muscle, rectus capitis lateralis, had its largest moment in lateral flexion, whereas the other muscles had large, posturally dependent moment arms appropriate for actions in flexion-extension. The observation that most rectus muscles have relatively large cross-sectional areas and high fast-fiber proportions suggests that the muscles may have important phasic as well as postural roles during head movement. © 1993 Wiley-Liss, Inc.  相似文献   

9.
In their dentition, acanthodians and placoderms differ from other fishes by the ontogenetie development and replacement of their teeth and by the histology of the functional elements (teeth, cutting edges of the jaws). In some cases special diets are indicated. In general, however, their dentition seems to have been less effective than that of elasmobranchs and teleostomes. This fact may partly account for their early extinction.
Die Eigenart des Gebisses der Aoanthodier und Placodermen inbezug auf die Zahnbildung (Ontogenese), den Zahnersatz und den histologischen Bau der funktionalen Elemente (Zähne, Schneidekanten des Kieferknochens) wird dargestellt. Aus dem Bau des Gebisses läßt sich die Nahrung dieser Tiere teilweise erschließen. Das eigenartige Gebiß verursaehte vermutlich eine Konkurrenzunterlegenheit beim Nahrungserwerb gegenüber den Elasmobranchiern und Teleostomen, vielleicht einer der Gründe, der zum frühen Aussterben der Acanthodier und Placodermen führte.  相似文献   

10.
The lack of adequate recipient vessels often complicates microvascular breast reconstruction in patients who have previously undergone mastectomy and irradiation. In addition, significant size mismatch, particularly in the outflow veins, is an important contributor to vessel thrombosis and flap failure. The purpose of this study was to review the authors' experience with alternative venous outflow vessels for microvascular breast reconstruction. In a retrospective analysis of 1278 microvascular breast reconstructions performed over a 10-year period, the authors identified all patients in whom the external jugular or cephalic veins were used as the outflow vessels. Patient demographics, flap choice, the reasons for the use of alternative venous drainage vessels, and the incidence of microsurgical complications were analyzed. The external jugular was used in 23 flaps performed in procedures with 22 patients. The superior gluteal and transverse rectus abdominis musculocutaneous (TRAM) flaps were used in the majority of the cases in which the external jugular vein was used (72 percent gluteal, 20 percent TRAM flap). The need for alternative venous outflow vessels was usually due to a significant vessel size mismatch between the superior gluteal and internal mammary veins (74 percent). For three of the external jugular vein flaps (13 percent), the vein was used for salvage after the primary draining vein thrombosed, and two of three flaps in these cases were eventually salvaged. In three patients, the external jugular vein thrombosed, resulting in two flap losses, while the third was salvaged using the cephalic vein. A total of two flaps were lost in the external jugular vein group. The cephalic vein was used in 11 flaps (TRAM, 64.3 percent; superior gluteal, 35.7 percent) performed in 11 patients. In five patients (54.5 percent), the cephalic vein was used to salvage a flap after the primary draining vein thrombosed; the procedure was successful in four cases. In three patients, the cephalic vein thrombosed, resulting in two flap losses. One patient suffered a thrombosis after the cephalic vein was used to salvage a flap in which the external jugular vein was initially used, leading to flap loss, while a second patient experienced cephalic vein thrombosis on postoperative day 7 while carrying a heavy package. There was only one minor complication attributable to the harvest of the external jugular or cephalic vein (small neck hematoma that was aspirated), and the resultant scars were excellent. The external jugular and cephalic veins are important ancillary veins available for microvascular breast reconstruction. The dissection of these vessels is straightforward, and their use is well tolerated and highly successful.  相似文献   

11.
To elucidate compositional changes of the veins with aging, the authors investigated the relationships among element contents in the internal jugular veins, in which a higher accumulation of calcium and phosphorus occurred with aging. The subjects consisted of 15 men and 10 women, ranging in age from 40 to 98 yr. The element contents of the internal jugular veins were determined by inductively coupled plasma-atomic emission spectrometry. It was found that there were extremely significant direct correlations among the contents of calcium, phosphorus, magnesium, and sodium in the internal jugular vein. In addition, very significant direct correlations were also found both between zinc and either iron or silicon contents and between sulfur and iron contents in the vein. As calcium and phosphorus increased in the internal jugular vein, the mass ratios of Mg/Ca and Mg/P decreased gradually in the vein, whereas the mass ratio of Ca/P hardly decreased. These results indicated that with regard to both the relationships among the contents of calcium, phosphorus, and magnesium and the changes of the mass ratios of Mg/Ca and Mg/P, the internal jugular vein was very similar to the arteries.  相似文献   

12.
This study demonstrates that the silver technique of Grimelius (Acta Soc. Med. Ups. 73:243–270, 68) is ideally suited for the study of cardiovascular chromaffin cells in lampreys. This method showed that in the Southern Hemisphere lamprey, Geotria australis, the distribution of chromaffin cells differs from that described for holarctic species. In G. australis, the chromaffin cells are found mainly in the sinus venosus, atrium, and nearby regions of the cardinal and jugular veins, and they are absent from the ventricle and conus arteriosus. The location and discreteness of the large accumulation of chromaffin cells in the lateral wall of the right posterior cardinal vein of adults resemble those of the precardiac axillary bodies of elasmobranchs. Chromaffin cells become more abundant during metamorphosis. The possible phylogenetic and functional significance of lamprey chromaffin cells is briefly discussed.  相似文献   

13.
Previous studies have demonstrated that the ventral aorta of the dogfish shark, Squalus acanthias, responds to a variety of cell-signaling agents. To investigate the generality of vasoactive receptors in the shark vasculature, in particular a conductance artery (anterior mesenteric) and vein (posterior intestinal), I measured the effect of acetylcholine, endothelin, nitric oxide, natriuretic peptides, and prostaglandins on tension in isolated rings from these vessels. Both vessels responded to these agents, and responses to receptor-specific ligands for endothelin and natriuretic peptide receptors suggest that B-type endothelin receptors are expressed in both vessels and that the artery expresses both A- and B-type natriuretic peptide receptors; however, the vein (like the ventral aorta) expresses only the B-type natriuretic peptide receptor. My data suggest that a suite of signaling systems is ubiquitous in both arteries and veins in at least this elasmobranch species. Their role in hemodynamics and osmoregulation (perfusion of gill and rectal gland) remains to be determined.  相似文献   

14.

Background

Natural heterologous valved conduits with a diameter greater than 22 mm that can be used for right ventricular outflow tract reconstruction in adults are not commercially available. The purpose of this study was to measure by ultrasonography the maximum diameter of the distended jugular veins of horses and cattle, respectively, to identify a population of animals that would be suitable for post-mortem collection of jugular veins at sizes greater than 22 mm.

Methods

The study population included 60 Warmblood horses, 25 Freiberger horses, 20 Brown Swiss cows, and 20 Holstein cows (including 10 Holstein and 10 Red Holstein). The maximum cross-sectional diameter of the distended jugular veins was measured at a location half-way between the mandibular angle and the thoracic inlet. The thoracic circumference (heart girth length) was used as a surrogate of body size. The jugular vein diameters of the different populations were compared by analysis of variance and the association between heart girth length and jugular vein diameter was determined in each of the four study populations by linear regression analysis.

Results

There was considerable individual variation of jugular vein diameters within each of the four study populations. There was no statistically significant relationship between thoracic circumference and jugular vein diameter in any of the populations. The jugular vein diameters of Brown Swiss cows were significantly larger than those of any of the other populations. Warmblood horses had significantly larger jugular vein diameters compared to Freiberger horses.

Conclusion

The results of this study suggest that the production of bovine or equine xenografts with diameters of greater than 22 mm would be feasible. Differences between species and breeds need to be considered. However, prediction of the jugular vein diameter based on breed and heart girth length in an individual animal is inaccurate.  相似文献   

15.
Thrombin injection into white rats jugular vein in dose 20 units on 200 g of body mass results in more considerable release of plasminogen activator in blood of renal vein as compared with blood of cava inferior and jugular veins. In this case the fibrinolytic activity of kidney cortical part decreases, but in medullar part it does not alter. The decrease of antiplasmin content in blood of renal vein is due to alpha 2-macroglobulins, in blood of jugular and cava inferior veins--to alpha 1-antithrypsin.  相似文献   

16.
目的:检测去细胞处理牛颈静脉的生物相容性.方法:去细胞处理牛颈静脉,与新鲜牛颈静脉分别于兔皮下包埋,术后2,4,12周取材,HE染色;进行血浆蛋白吸附和血小板粘附实验,检测血液相容性.结果:包埋早期有炎性细胞浸润,后期炎性细胞消失,以成纤维细胞为主.去细胞牛颈静脉与新鲜牛颈静脉血浆蛋白吸附和血小板粘附无显著差异.结论:去细胞牛颈静脉有良好的生物相容性.  相似文献   

17.
The lower jaw in Melanognathus gen. nov. and several other Devonian dipnoans is described and compared with that in Neoceratodus. It is a most conservative structure, which apart from the effect of the retrogressive development of the skeleton has hardly changed since Devonian times. A new interpretation of the sensory canal bones is given. With respect to these elements and the structure of the lower jaw as a whole, the dipnoans differ fundamentally from the rhipidistid crossopterygians, tetrapods and aetinopterygians. Several resemblances to the lower jaw in holocephalians are demonstrated. The results confirm the view that the Dipnoi comprise an early specialized and isolated group, perhaps more closely related to the elasmo-branchiomorphs than to the teleostomes and tetrapods.  相似文献   

18.
Isolated vessels from four elasmobranchs, yellow stingray (Urolophus jamaicensis), clearnose skate (Raja eglanteria), ghost shark (Hydrolagus novaezelandiae), and spiny dogfish (Squalus acanthias), were examined for the presence of spontaneous contractions (SC). SC were observed in otherwise unstimulated dorsal aortas (DA) from stingray and ghost shark, but not in skate DA. Unstimulated ventral aortas (VA) did not exhibit SC. After treatment of VA with a contractile agonist, SC appeared in stingray and skate but not ghost shark or dogfish. SC in stingray VA were subsequently inhibited by either epinephrine (10(-5) M) or indomethacin (10(-4) M). Agonist contraction also elicited strong SC in ductus Cuvier from stingray, but not from ghost shark or dogfish. SC in dogfish hepatic portal veins (HPV) produced a rhythmical oscillation in tension. The frequency of HPV SC was highest (approximately 1 min(-1)) in intact veins and lower (approximately 3 min(-1)) in vein segments, indicative of a dominant pacemaker in the intact vessel. SC in HPV were depressed during the first 30 min of hypoxia, but there was substantial recovery over an additional 30 min of hypoxia and complete recovery upon return to normoxia. Addition of 80 mM KCl completely inhibited HPV SC and lowered resting tone. These results show that SC are a common feature of elasmobranch vessels and there appears to be a correlation between swimming behavior and the propensity for SC. KCl inhibition of SC and tonus in HPV is highly unusual for vascular smooth muscle.  相似文献   

19.
The vascularization of the telencephalic choroid plexus of the sterlet Acipenser ruthenus, a ganoid fish, was examined by vascular corrosion casting and by light and transmission electron microscopy. The arterial supply is from the dorsal mesencephalic artery via: 1) the ventral choroidal arteries (left and right); 2) the dorsal choroidal arteries (left and right); 3) the caudal choroidal arteries (left and right); 4) the ventral arteries of the dorsal sac; and, from the olfactory arteries, via 5) the rostral choroidal arteries. The venous drainage is mainly through a single main choroidal vein that can take various courses either directly to the anterior cardinal vein or via the middle cerebral vein to the anterior cardinal vein. To a lesser extent, the plexus is drained via the lateral telencephalic veins and the ventral vein of the dorsal sac to the middle cerebral vein. By angioarchitecture and form, the plexus can be subdivided into five distinct parts: the surface network, the median folds, the large lateral folds, the small lateral folds, and the area common to the bottom of the dorsal sac and the telencephalic plexus. Diameters of terminal vessels as measured from vascular corrosion casts and from paraplast, semithin, and ultrathin sections were never less than 10 micron. It is suggested that the different areas in one plexus may have different functions with respect to secretion and absorption of cerebrospinal fluid.  相似文献   

20.
The early development of the lymphatic system was studied in embryos of an inbred strain of the laboratory mouse. During the first stage of its development the system is represented by a more or less regular series of small and blind-ending outgrowths of the major embryonic veins which develop in a cranio-caudalward direction from the jugular to the pelvic region. As a result of differences in growth rates of adjacent anatomical structures this series of early lymphatic primordia becomes subdivided into 4 singular primordia and 12 groups of primordia. After the constituents of each group of early primordia have fused, 16 isolated lymphatic plexuses (sacs) are formed of which 14 are in bilaterally symmetric and 2 are in a median line position: i.e. bilaterally: (1) the jugulo-axillary lymph sac situated lateral to the anterior cardinal vein and dorsal to the primitive ulnar vein and its major branch, the external mammary vein, (2) the paratracheal lymph plexus situated medial to the anterior cardinal vein, (3) the internal thoracic lymph plexus situated lateral to the thoracic part of the posterior cardinal vein, (4) the thoracic ducts situated medial to the thoracic part of the posterior cardinal vein, (5) the lumbar lymph plexus situated dorso-lateral to the abdominal part of the posterior cardinal vein, (6) the subcardinal lymph plexus and (7) the iliac lymph plexus situated ventro-lateral to the abdominal part of the posterior cardinal vein; and in the median line: (8) the subtracheal lymph plexus situated at the confluence of the pulmonary veins and (9) the mesenteric lymph plexus situated near the confluence of the splenic and the superior mesenteric veins. Except for some openings at the jugulo-subclavian confluence all connections with the veins disappear. From the primordia extensions grow out centrifugally. They invade the surrounding tissues and, in part, fuse with similar sprouts of adjacent primordia. In this way a continuous system of lymph truncs is formed that opens into the venous system at the jugulo-subclavian confluence.  相似文献   

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