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1.
New skeletal elements are reported of the holotype specimen Australovenator wintonensis, from the type locality, near Winton, central western Queensland. New elements include left and right humeri, right radius, right radiale, right distal carpal 1, near complete right metacarpal I, left manual phalanx II-1, left manual phalanx II-2, near complete left manual phalanx II-3 and a left manual phalanx III-3. These new elements combined with those previously described are compared against other neovenatorids.  相似文献   

2.
In recent years some buffalo farms in Campania have reported the birth of calves with limb malformation, especially with transversal hemimelia. We investigated 20 Mediterranean Italian buffaloes (8 males and 12 females) from one day to six months of age, of which 10 were affected by transversal hemimelia (group 1) and 10 were healthy controls (group 2). The following clinical and radiological patterns were observed in the malformed animals: hind limbs amputated, the right amputated off the second tarsus bones and the left amputated off the proximal epiphysis metatarsus, and the right thoracic limb hypoplasic (1 female); left hind limb amputated off the proximal epiphysis metatarsus (2 females and 1 male); left hind limb amputated off the third tarsus bones (1 female); left hind limb amputated off the tibia (1 female and 1 male); left hind limb amputated off the distal epiphysis metatarsus (1 female); left hind limb amputated off the first phalanx (1 male); right hind limb amputated off the proximal epiphysis metatarsus (1 male). In their malformed limbs all the animals presented more or less developed outlines of claws. The mean rate of SCE/cell in animals with transversal hemimelia was 8.80 +/- 3.19, that of the controls 6.61 +/- 2.73. The difference was statistically significant (P < 0.001).  相似文献   

3.
The vaquita ( Phocoena sinus ) manus was examined in 16 individuals. The carpus has a proximal row of three bones and a cartilaginous accessory carpal element distocaudal to the ulna. Five metacarpal bones are present. A process in distocaudal aspect of Metacarpal III and an additional digital ray were present in all individuals examined. The number of phalanges in the additional digital ray varied among individuals and, sometimes, between the left and the right flipper of the same individual. The suggested phalangeal formula is I-1, II-7-8, III-6-7, IV-0-3, V-3-4, VI-1. The presence of this particular form of polydactyly may be the result of genetic drift in the small vaquita population.  相似文献   

4.
Appendicular elements of the sauropod dinosaur Suuwasseaemilieae, from the Upper Jurassic Morrison Formation of Montana, USA, display a peculiar mix of autapomorphic and plesiomorphic features. While more similar in overall morphology to Apatosaurus than other flagellicaudatans, the coracoid of Suuwassea lacks the quadrangular shape of Apatosaurus. The humerus of Suuwassea bears a pronounced proximal tuberculum, a feature seen elsewhere only in saltasaurine titanosaurian sauropods. The rectangular proximal articular surface of the tibia is proportioned neither like Diplodocus nor Apatosaurus type specimens, although this region may be intraspecifically variable. The pes of Suuwassea possesses plesiomorphically elongate phalanges and a small, uncompressed ungual, unlike other flagellicaudatans except Dyslocosaurus. The localization of tooth marks on the pedal elements suggests that sauropod feet may have been singled out by scavengers, as has been noted for elephants.  相似文献   

5.
The hind limb step cycle of Iguana is described and compared with other lizards. In generalized lizards with well developed limbs, the femur retracts through a large arc and rotates as it retracts, flexion of the crus on the metatarsus occurs during the initial part of the propulsive phase and extension of the knee and ankle during the final part, the crus rotates to face laterally, the metatarsus is laterally directed at the time of pedal plantarflexion, and pedal plantarflexion involves an initial rotation of the metatarsus around its long axis followed by an extension of the ankle joint. The evolutionary significance of the differences in the hind limb step cycle of lizards and salamanders is considered and it is shown that in many, but not all, features, primitive reptiles would have been like salamanders. The primitive step cycle differs from the mammalian pattern in the large amount of rotation of the limb segments, the large amount of femoral retraction, and the reduced amount of lateral movement of the hip relative to the knee that occurs during femoral retraction.  相似文献   

6.
《Comptes Rendus Palevol》2016,15(8):978-987
In order to assess the antiquity of derived human lateral (lesser) toe morphology, the SKX 16699 Early Pleistocene pedal proximal phalanx from Swartkrans (South Africa) was compared to samples of pedal phalanges attributed to Pliocene/Pleistocene australopithecines, Homo naledi and Late Pleistocene Homo. In contrast to australopith lateral phalanges, the SKX 16699 phalanx exhibits an absolutely (and probably relatively) short length, limited plantar diaphyseal curvature, proximal-to-midshaft and mid-dorsoplantar flexor sheath insertions, and a marked proximodorsal orientation of the metatarsal facet. SKX 16699 is intermediate between the australopith phalanges and later Homo ones in its modest dorsal diaphyseal curvature and mid-dorsoplantar metatarsophalangeal collateral ligament insertion areas. Its diaphyseal robustness is similar to that of Homo phalanges, but overlaps the range of later australopith ones. This combination of features and the close morphological affinities of SKX 16699 to later Homo proximal pedal phalanges suggest the emergence of a distinctly human lateral forefoot by the initial Early Pleistocene.  相似文献   

7.
This paper applies multivariate statistical methods to a data set of weed relevés from arable fields in two different habitat types of coastal and mountainous escarpments in Southern Oman. The objectives were to test the effect of environmental gradients, crop plants and time on weed species composition, to rank the importance of these particular factors, and to describe the patterns of species composition and diversity associated with these factors. Through the application of TWINSPAN, DCA and CCA programs on data relating to 102 species recorded in 28 plots and farms distributed in the study area, six plant communities were identified: I- Dichanthium micranthum, II- Cynodon dactylonD. micranthum, III- Convolvulus arvensis, IV- C. dactylonSonchus oleraceus, V- Amaranthus viridis and VI- Suaeda aegyptiacaAchyranthes aspera. The ordination process (CCA) provided a sequence of plant communities and species diversity that correlated with some anthropogenic factors, physiographic variables and crop types. Therefore, length of time since farm construction, disturbance levels and altitude are the most important factors related to the occurrence of the species. The perennial species correlated with the more degraded mountain areas of new farm stands, whereas most of the annuals correlated with old lowland and less disturbed farms.  相似文献   

8.
9.
SV40-transformed cells of C57BL/6 (B6) mouse origin (H-2b) express four distinct predominant antigenic sites, I, II, III, and IV, on SV40 large tumor (T) Ag that are recognized by SV40 T Ag-specific CTL clones. In this study, we selected SV40 T Ag-positive cell lines which had lost one or more of the antigenic sites, by in vitro cocultivation of a SV40-transformed B6 mouse kidney cell line (K-0) with SV40 T Ag site-specific CTL clones, Y-1 (site I specific), Y-2 (site II specific), Y-3 (site III specific), and Y-4 (site IV specific). All of the CTL-resistant cell lines expressed large quantities of cell surface H-2 class I Ag. K-1 cells selected by CTL clone Y-1 lost the expression of antigenic sites I, II, and III, but not site IV. K-2 and K-3 cells selected by CTL clones Y-2 and Y-3, respectively, were found to be negative for sites II and III but expressed sites I and IV. K-4 cells selected by CTL clone Y-4 lost the expression of only site IV. K-1,4 cells (sites I-, II-, III-, IV-) were selected from K-1 cells by cocultivation with CTL clone Y-4, K-2,4 cells (sites I+, II-, III-, IV-) were selected from K-2 cells by CTL clone Y-4. K-3,1 cells (sites I-, II-, III-, IV+) were selected from K-3 cells by CTL clone Y-1, and K-3,1,4 cells (sites I-, II-, III-, IV-) were selected from K-3,1 cells by CTL clone Y-4. From K-4 cells, K-4,1 cells (sites I-, II-, III-, IV-) and K-4,3 cells (sites I+, II-, III-, IV-) were selected by CTL clone Y-1 and Y-3, respectively. The antigenic site loss variant cell lines K-1, K-1,4, K-3,1 K-3,1,4, K-4,1, and K-4,3 synthesized SV40 T Ag molecules of 75, 75, 78, 78, 81, and 88 kDa, respectively. Expression of wild-type SV40 T Ag in the antigenic site loss variants by infection with SV40 or transfection with cloned SV40 DNA restored the CTL recognition sites on the variant cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
New material of Natchitochia from the Bartonian Archusa Marl Member is described here, including thoracic, lumbar, sacral, and caudal vertebrae, an innominate, proximal femur, and pedal? phalanx. The vertebrae and innominate are similar to those of Qaisracetus and Georgiacetus. The structure of the caudal vertebrae support previous observations that as sacral vertebrae disconnect from the sacrum, they become caudalized, developing hemal processes on the posteroventral margins of the bodies, reminiscent of chevron bones associated with true caudal vertebrae. The innominate of Natchitochia shares an elongate ilium and pubis with Qaisracetus and Georgiacetus, which differ from the innominata of the more apomorphic archaeocetes. Comparison of archaeocete innominata and sacra in a phylogenetic context indicates that the apomorphic sacrum composed of 4 vertebrae (Pakicetus, Ambulocetus, Rodhocetus, Maiacetus) was reduced to 3 (Qaisracetus) to 2 (Protocetus?, Natchitochia) to 0 (Georgiacetus, Basilosauridae), while the innominata remained robust, supporting a large hind limb until the origin of the Basilosauridae. In Georgiacetus, the innominate is large but detached from the vertebral column, preventing the use of the hind limb in terrestrial locomotion. More crownward cetaceans for which the innominate is known display greatly reduced innominata and hind limbs are disconnected from the vertebral column.  相似文献   

11.
Previous discussions of the mode of life of Hypsilophodon (Lower Cretaceous, England) are reviewed, and it is concluded that this primitive ornithopod was cursorial. There are no specific adaptations for an arboreal mode of life, and the hallux was not opposable. Metatarsal I was closely applied along its length to metatarsal II, and the first digit moved parallel to or. slightly away from the other digits. Relative to the trunk, the hind limb is long, with an elongate tibia and metatarsus, so that the proportions of the different regions fall in the range for cursorial mammals.  相似文献   

12.
de la Fuente M.S. & Fernández, M.S. 2010: An unusual pattern of limb morphology in the Tithonian marine turtle Neusticemys neuquina from the Vaca Muerta Formation, Neuquén Basin, Argentina. Lethaia, Vol. 44, pp. 15–25. Here, we report an unusual pattern in the manus and pes morphology of the Tithonian marine turtle Neusticemys neuquina. We analyse the forelimbs of two previously known specimens and describe the hind limbs of two previously undescribed specimens. Neusticemys neuquina is characterized by a relative elongation of both the forelimb and hind limb, compared with stem Chelonoidea, as well as an elongation of the pedal digit V, achieved through the elongation of the bones, as well as a moderate hyperphalangy. The elongation of pedal digit V is the most striking feature of N. neuquina, a feature unknown in other turtles. □Limb morphology, Neusticemys neuquina, Tithonian turtle.  相似文献   

13.
Structures of the principal O-glycosides from the major cell surface sialoglycoprotein (ASGP-1) of the MAT-B1 and MAT-C1 ascites sublines of the 13762 rat mammary adenocarcinoma have been determined. Oligosaccharitols were released by alkaline borohydride treatments of ASGP-1 and purified by gel filtration, DEAE-Sephadex ion exchange chromatography, and high performance liquid chromatography. On the basis of carbohydrate composition, methylation analysis, periodate oxidation, and exoglycosidase digestion, the five major oligosaccharides released by mild alkaline borohydride were assigned the following structures: Component II-3: (NeuAc alpha 2----3Gal beta 1----4GlcNAc beta 1----6)Ga 1 NAcOH(3----1 betaGa 1 3----2 alpha NeuAc) III-2a: (Ga 1 beta 1----4G1cNAc beta 1----6)Ga 1 NAcOH(3----1 beta Ga 1 3----2 alpha NeuAc) III-2c: (Ga 1 alpha 1----3Ga 1 beta 1----4G1cNAc beta 1----6) Ga 1 NAcOH(3----1 beta Ga 1 3----2 alpha NeuAc) IV-1a: (Ga 1 beta 1----4G 1 cNAc beta 1----6)Ga 1 NAcOH(3----1 beta Ga 1) IV-1c: (Ga 1 alpha 1----3Ga 1 beta 1----4G 1 cNAc beta 1----6) Ga 1 NAcOH(3----1 beta Ga 1) Fucosylated derivatives of III-2a, IV-1a, and IV-1c were found in smaller amounts with the fucose tentatively assigned to the 2-position of the lactosamine galactose. Components II-3, III-2a, and the fucosylated derivative of III-2A were found in both MAT-B1 and MAT-C1 sublines. The alpha-galactosides were found in detectable quantities only in subline MAT-B1. Oligosaccharides from MAT-C1 cells were enriched in sialic acid when compared to those from MAT-B1 cells. These results suggest that the 13762 ascites sublines, which bear different oligosaccharides, will provide models useful for the investigation of mechanisms regulating the expression of structures of the larger O-linked oligosaccharides.  相似文献   

14.
On the basis of studies on serial sections of larval Ranodon sibiricus limbs and published data, the hypothesis of the origin of tetrapod limbs from the biserial archipterygium is proposed. The mesomeres of the central axis of the biserial fin correspond (in proximodistal direction) to the humerus, ulna, ulnare, all carpalia distalia, metacarpale 1, and phalanges of the first digit in the forelimb of caudate amphibians and to the femur, fibula, fibulare, tarsalia distalia, metatarsale 1, and phalanges of the first digit in the hind limb. The preaxial elements of the zygopodium and autopodium, which are positioned proximal to the digital arch, correspond to the preaxial rays of the biserial fin, and digits 2–5 correspond to its postaxial rays. As the fin transformed into the limb, the central axis curved preaxially, forming the digital arch and resulting in partial reduction and fusion of preaxial rays.  相似文献   

15.
The scincid lizard clade Lerista provides an exceptional model for studying the mode of substantial evolutionary transformations, comprising more than 90 species displaying a remarkable variety of body forms. Patterns of character evolution in this clade, inferred from reconstructed ancestral states, are at least partly consistent with the correlated progression model of macroevolutionary change. At each stage in the transition to a highly elongate, limb-reduced body plan, alterations to the lengths of the forelimb and hind limb are accompanied by compensatory changes in snout-vent length (or vice versa), preserving locomotory ability. Nonetheless, there is evidence for moderate dissociation of hind limb evolution in some lineages, while tail length has evolved effectively independently of the substantial alterations to the lengths of the body and limbs. This indicates a significant role of evolutionary and developmental modularity in the divergence of body form within Lerista, and emphasises the potential variability of the strength of functional constraints within organisms and among lineages. Trends toward a highly elongate, functionally limbless body plan may be attributed primarily to a combination of the interdependence of changes in snout-vent length and limb lengths and the very low probability of re-elaborating structurally reduced limbs. Similar asymmetries in the probabilities of interrelated phenotypic changes may be a significant cause of evolutionary trends resulting in the emergence of higher taxa. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

16.
In this note we reassess the position of putative pedal phalanges of some South American noasaurid theropods (Abelisauroidea). Noasaurids were considered as to be distinctive abelisauroids with a peculiar “sickle claw” on the second toe of the foot, convergently developed with that of deinonychosaurians. Among noasaurids, the Argentinean species Noasaurus leali (latest Cretaceous) and Ligabueino andesi (Early Cretaceous) are known from incomplete specimens, including dissarticulated non-ungueal phalanges, and, in N. leali, a claw. A detailed overview of these elements indicates that the supposed raptorial claw of the second pedal digit of N. leali actually belongs to the first or second finger of the manus, and the putative pedal non-ungual phalanges of both genera also pertain to the manus. Thus, the new interpretations of noasaurid pedal morphology blur the distinctions between Noasauridae and Velocisauridae proposed by previous authors. Finally, we suggest, on the basis of phalangeal and metacarpal morphology, that abelisaurids probably lost their manual claws by means of the loss of function of the HOXA11 and HOXD11 genes. Thus Noasauridae differs from Abelisauridae in retaining plesiomorphic long forelimbs with well developed claws, as occurs plesiomorphically in most basal theropods (e.g., Coelophysis).  相似文献   

17.
The fossil fauna of the Santana Formation (Early Cretaceous) comprises many distinct taxa, but crocodylomorphs are poorly understood. Here we describe a new specimen (MPSC-R1137) that consists of a complete hind limb found in the Crato Member, the basal section of the Santana Formation. Based on the characteristics of the fibula (e.g., pronounced variation of the shaft width) and length proportions of the femur and tibia, this specimen can be distinguished from Caririsuchus camposi and Araripesuchus gomesii, which are known from the Romualdo Member (the upper lithostratigraphic unit of the Santana Formation). The only crocodylomorph formally described from the Crato Member is Susisuchus anatoceps, whose holotype lacks elements of the hind limb. On the basis of a comparative anatomical study of the hind limb, which shows no similarities between MPSC-R1137 and other crocodylomorphs from the Araripe Basin, we tentatively classify this new specimen as cf. Susisuchus sp., and provide new anatomical information for this rather derived crocodylomorph.   相似文献   

18.
Bones of the lower extremity have been recovered for up to nine different individuals of Homo floresiensis - LB1, LB4, LB6, LB8, LB9, LB10, LB11, LB13, and LB14. LB1 is represented by a bony pelvis (damaged but now repaired), femora, tibiae, fibulae, patellae, and numerous foot bones. LB4/2 is an immature right tibia lacking epiphyses. LB6 includes a fragmentary metatarsal and two pedal phalanges. LB8 is a nearly complete right tibia (shorter than that of LB1). LB9 is a fragment of a hominin femoral diaphysis. LB10 is a proximal hallucal phalanx. LB11 includes pelvic fragments and a fragmentary metatarsal. LB13 is a patellar fragment, and LB14 is a fragment of an acetabulum. All skeletal remains recovered from Liang Bua were extremely fragile, and some were badly damaged when they were removed temporarily from Jakarta. At present, virtually all fossil materials have been returned, stabilized, and hardened. These skeletal remains are described and illustrated photographically. The lower limb skeleton exhibits a uniquely mosaic pattern, with many primitive-like morphologies; we have been unable to find this combination of ancient and derived (more human-like) features in either healthy or pathological modern humans, regardless of body size. Bilateral asymmetries are slight in the postcranium, and muscle markings are clearly delineated on all bones. The long bones are robust, and the thickness of their cortices is well within the ranges seen in healthy modern humans. LB1 is most probably a female based on the shape of her greater sciatic notch, and the marked degree of lateral iliac flaring recalls that seen in australopithecines such as “Lucy” (AL 288-1). The metatarsus has a human-like robusticity formula, but the proximal pedal phalanges are relatively long and robust (and slightly curved). The hallux is fully adducted, but we suspect that a medial longitudinal arch was absent.  相似文献   

19.
Many aspects of the relationship between the demyelinating pathology and platelet function need to be elucidated. Thus, the activity of NTPDase and 5'-nucleotidase enzymes was analyzed in platelets from rats demyelinated with ethidium bromide (EB) and previously treated with ebselen (Ebs) and vitamin E (Vit. E). The animals were divided into four groups: for ebselen, the groups were: I-control (saline), II-(saline and Ebs), III-(EB) and IV-(EB and Ebs); and for vitamin E, the groups were: I - control (saline), II-(saline and Vit. E), III-(EB) and IV-(EB and Vit. E). After 3 and 21 days, the blood was collected and the platelets were separated for enzymatic assays. For the treatment with Ebs, the NTPDase activity for ATP substrate was significantly lower in groups II, III and IV (p < 0.05) after 3 days, while after 21 days, a reduction was observed in group III (p < 0.05). ADP hydrolysis was reduced in group II (p < 0.05) and increased in group IV (p < 0.05) after 3 days, while after 21 days there was an increase in group IV (p < 0.05). In the treatment with Vit. E, ATP hydrolysis was lower in groups II, III and IV (p < 0.05) after 3 and 21 days. ADP hydrolysis was increased in group II (p < 0.05) after 3 days, and in group IV (p < 0.05) after 21 days. However, 5'-nucleotidase activity was not altered by the treatments. These findings demonstrate that NTPDase activity in platelets is diminished in demyelinating events and the treatments with Ebs and Vit. E modulated adenine nucleotide hydrolysis.  相似文献   

20.
A comparative study of the appendicular skeletal morphology, with a particular emphasis on the autopodial elements (manus and pes), of the extinct caviine rodent Microcavia criolloensis (Late Pleistocene, Uruguay), together with that of living species of Microcavia and some allied caviines is performed. Burrow‐digging and above‐ground behaviour by M. criolloensis could have evolved in the Late Pleistocene, as with its relative M. australis in the Recent. This is suggested based on the morphology of preserved articulated skeletons along with fossil burrow‐like structures. The most remarkable features are: in its forelimb, where the humerus has a structure that would have allowed it to perform similar activities to M. australis, based on humeral width across the epicondiles relative to total humerus length index and a good resistance as indicated by high values relating the diameter of the diaphysis to its total length. Qualitative comparison shows that M. criolloensis had a stout, wide manus with relatively short digits including short, wide phalanges, despite its large size. In its hind limb there is a stout hind‐foot with relatively short and wide metatarsals and phalanges, as compared with those of the recent species, that could arguably be considered a useful tool for shovelling out displaced soil. The generalized morphology suggests above‐ground behaviour together with digging ability. The environmental adaptations of M. criolloensis are also briefly discussed, which seem to differ from those of its extant relatives. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 795–806.  相似文献   

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