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1.
The taxonomic affinities of the Eppelsheim femur, known as Paidopithex, have been unclear for more than a century. Over the years, due to similarities with Pliopithecus, some authors have considered it a large pliopithecid, while others refer to it as Dryopithecus. The issue could not be resolved, because no definitive Dryopithecus femora were available. With the discovery of the Dryopithecus laietanus skeleton from Can Llobateres (CLl 18800), it has become possible to test the attribution of the Eppelsheim femur to Dryopithecus on the basis of direct morphological and metrical comparisons. By means of allometric techniques, we show that the Eppelsheim and D. laietanus femora fit different hindlimb morphologies with regard to relative length and relative head/neck size, with Paidopithex significantly differing from Dryopithecus, but more closely resembling Pliopithecus. Paidopithex also differs from Dryopithecus in other important aspects, such as its lower neck/shaft angle, lack of elevation of the femoral head above the greater trochanter, more posteriorly oriented lesser trochanter, and proximal shaft diameter thicker anteroposteriorly than mediolaterally. In these features, Paidopithex most closely resembles Pliopithecus in spite of differences in body mass (ca. 22 kg vs. ca. 10 kg, respectively). These features suggest that Paidopithex used a primitive locomotor pattern associated with arboreal quadrupedalism, instead of the more derived pattern displayed by Dryopithecus. Currently available evidence confirms that the attribution of Paidopithex to Dryopithecus can be rejected. Paidopithex could be a large and otherwise unknown pliopithecid, but the possibility cannot be ruled out that it represents a third kind of catarrhine.  相似文献   

2.
The OH5 cranium, holotype of Paranthropus boisei consists of two main portions that do not fit together: the extensively reconstructed face and a portion of the neurocranium. A physical reconstruction of the cranium was carried out by Tobias in 1967, who did not discuss problems related to deformation, although he noted a slight functional asymmetry. Nevertheless, the reconstructed cranium shows some anomalies, mainly due to the right skewed position of the upper calvariofacial fragment and uncertainty of the relative position of the neurocranium to the face, which hamper further quantitative analysis of OH5′s cranial geometry. Here, we present a complete virtual reconstruction of OH5, using three-dimensional (3D) digital data, geometric morphometric (GM) methods and computer-aided design (CAD) techniques. Starting from a CT scan of Tobias’s reconstruction, a semi-automatic segmentation method was used to remove Tobias’s plaster. The upper calvariofacial fragment was separated from the lower facial fragment and re-aligned using superposition of their independent midsagittal planes in a range of feasible positions. The missing parts of the right hemiface were reconstructed using non-uniform rational basis-spline (NURBS) surface and subsequently mirrored using the midsagittal plane to arrive at a symmetrical facial reconstruction. A symmetric neurocranium was obtained as the average of the original shape and its mirrored version. The alignment between the two symmetric shapes (face and neurocranium) used their independent midsagittal plane and a reference shape (KNM-ER 406) to highly reduce their degrees of freedom. From the series of alternative reconstructions, we selected the middle of this rather small feasible range. When reconstructed as a range in this way, the whole cranial form of this unique specimen can be further quantified by comparative coordinate-based methods such as GM or can be used for finite element modeling (FEM) explorations of hypotheses about the mechanics of early hominin feeding and diets.  相似文献   

3.

Objective

Brown adipose tissue (BAT), a specialized tissue for thermogenesis, plays important roles for metabolism and energy expenditure. Recent studies validated BAT’s presence in human adults, making it an important re-emerging target for various pathologies. During this validation, PET images with 18F-FDG showed significant uptake of 18F-FDG by BAT under certain conditions. Here, we demonstrated that Cerenkov luminescence imaging (CLI) using 18F-FDG could be utilized for in vivo optical imaging of BAT in mice.

Methods

Mice were injected with 18F-FDG and imaged 60 minutes later with open filter and 2 minute acquisition. In vivo activation of BAT was performed by norepinephrine and cold treatment under isoflurane or ketamine anesthesia. Spectral unmixing and 3D imaging reconstruction were conducted with multiple-filter CLI images.

Results

1) It was feasible to use CLI with 18F-FDG to image interscapular BAT in mice, with the majority of the signal (>85%) at the interscapular site originating from BAT; 2) The method was reliable because excellent correlations between in vivo CLI, ex vivo CLI, and ex vivo radioactivity were observed; 3) CLI could be used for monitoring BAT activation under different conditions; 4) CLI signals from the group under short-term isoflurane anesthesia were significantly higher than that from the group under long-term anesthesia; 5) The CLI spectrum of 18F-FDG with a peak at 640 nm in BAT after spectral unmixing reflected the actual context of BAT; 6) Finally 3D reconstruction images showed excellent correlation between the source of the light signal and the location and physical shape of BAT.

Conclusion

CLI with 18F-FDG is a feasible and reliable method for imaging BAT in mice. Compared to PET imaging, CLI is significantly cheaper, faster for 2D planar imaging and easier to use. We believe that this method could be used as an important tool for researchers investigating BAT.  相似文献   

4.
本文通过粗壮池猿头骨新材料的初步观察得出,它与欧洲上猿的头骨比较接近,而在某些特征上又与现生长臂猿相似。这与牙齿和颌骨研究的结果是一致的。本文还对亚洲第三纪长臂猿类与其他同时代长臂猿类的关系作了初步的探讨,并对池猿的系统关系作了论述。  相似文献   

5.
An alternative to recent interpretations of locomotor and postural behaviour in Dryopithecus (Proconsul) africanus as characteristic of “brachiating” or “knuckle-walking” adaptations is suggested. Analysis of the available joint complexes of the D. africanus upper limb and consideration of criteria employed by some researchers demonstrate that reconstruction of positional behaviour in Miocene Hominoidea is extremely speculative. However, the direction and range of movement within the elbow and wrist complexes of D. africanus can be defined with reference to available articular surfaces. Movement capabilities were apparently similar to those of quadrupedal, palmigrade primates.  相似文献   

6.
The severity of the developmental disorders of the paraxial mesoderm and neuroectoderm must objectively be compared to determine which of the two structures is more deeply involved in the pathogenesis of encephaloschisis. In the present study, hamster fetuses were obtained from dams that had been treated with retinoic acid, and divided into two groups: fetuses with encephaloschisis and those without apparent external malformations in the cranium and face. Mid-sagittal serial sections of the head were prepared, histologically processed, and utilized for the reconstruction of the profile of the head structures. Using this reconstructed profile, we measured the length of the skull base bone structures (basisphenoid and basiocciput), which develop from the paraxial mesoderm, brain structures (mesencephalon and metencephalon), which develop from the neuroectoderm, and facial bone structures (nasal septum and hard palate), which develop from cephalic neural crest cells. The measured length of each structure was compared between the treated and control groups. It was found that treatment with retinoic acid resulted in significantly (P < 0.05) shortened lengths of the skull base bone structures both in fetuses with encephaloschisis and those without apparent external malformations in the cranium and face. In the brain structure of fetuses without encephaloschisis, as well as in the facial bone structures, however, this shortness was not observed. These results suggest that developmental disorders in the paraxial mesoderm may play an important role in the pathogenesis of encephaloschisis.  相似文献   

7.
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9.
It has been proposed that the pliopithecid Anapithecus hernyaki was hunted by the ape Dryopithecus brancoi based on analyses of the age and sex distribution of 25 individuals from the late Miocene site of Rudabánya, Hungary (ca. 10 Ma). In this study, the minimum number of individuals (MNI) and age distribution of the assemblage are recalculated and considered in relation to their sedimentary context. We suggest that Dryopithecus juveniles may be underrepresented in the assemblage as a consequence of taphonomic loss of deciduous teeth. Furthermore, we find that while Dryopithecus and Anapithecus were contemporaneous, there was little spatial overlap between them, as each taxon is primarily associated with a separate lithofacies. We conclude that when the revised estimates of MNI and age distribution of these primates are reconsidered in conjunction with their context of burial, the case for the Dryopithecus hunting hypothesis cannot be sustained.  相似文献   

10.
山顶洞101号头骨化石是东亚地区保存最为完整的化石之一,是探讨东亚地区现代人起源的重要研究材料。本文依据数据集中现生人的面部软组织平均分布,提出了计算机三维颅面复原方法,实现了101号头骨生前面貌的预测复原。主要包括三个步骤:首先使用CT完成了101号男性头骨和下颌骨仿制模型的三维重建。然后,利用计算机技术将现生人的面部软组织分布作为101号头骨的面部软组织分布,实现了颅面虚拟复原,并采用手工绘画技巧再现了复原面貌的形态特征。最后,提出了一种基于面部软组织分布和面貌统计形状模型的形态分析方法,实现了颅面复原结果的评估。山顶洞101号头骨的复原面貌具有头部较长、额头前倾、眉弓粗壮等特征,与101号头骨的几何形态基本一致。该技术再现了更新世晚期人类的脑颅及面部的形态特征,为古人类颅面复原的研究提供了技术支持和参考资料。  相似文献   

11.
2011年安徽白鹭洲发现战国时期保存完整的楚国贵族墓葬,因墓主人头发和发簪保存完好、墓主身份显赫而备受关注。该头骨保存完整,具有亚洲蒙古人种的特征,根据骨骼的形态推测其为女性,年龄为35-39岁。为展现该地区战国贵族妇女的容貌、丰富该地区考古多样性提供研究材料。本文首先使用高分辨率CT对该个体的头骨及下颌骨进行了扫描和重建,然后采用基于偏最小二乘回归的颅面复原方法实现生前容貌基本形态的复原。最后,结合考古资料,利用三维模型处理软件对面貌复原模型及其发饰进行了三维建模和纹理贴图等处理,提高了颅面复原模型的真实感,生动形象地再现战国贵族女性面部的形态特征。  相似文献   

12.
Fossil primates have been known from the late Miocene locality of Rudabánya since 1965. Numerous campaigns of collecting, sampling and excavation have been carried out since that time by several teams of researchers, but the sample of primates has never been fully catalogued and published. Here we provide a comprehensive list of all primate specimens from Rudabánya with provenience data and allocation to individuals. At the main locality of R II 16 individuals are attributed to Anapithecus and nine to Dryopithecus, based on dental remains. Anapithecus comes mostly from a layer of gray to black marl and Dryopithecus is found mostly in a less consolidated overlying black mud. However, both taxa are found in both layers. Anapithecus is represented by larger proportions of juveniles and females, and Dryopithecus by more adult and subadult males. Both species are represented primarily by dental remains, but those of Dryopithecus are more commonly associated with mandibles and maxillae, while in Anapithecus most individuals are represented by associated dentitions. Dryopithecus is better represented by postcrania other than phalanges. Anapithecus age and sex frequency distributions are more typical of those of carnivore and chimpanzee prey assemblages than Dryopithecus.  相似文献   

13.
河南新安金丝猴颅骨化石   总被引:5,自引:0,他引:5  
本文记述了出自河南省新安县游沟村八陡山的一个基本完整的猴类颅骨化石.该颅骨骨缝已全部愈合,牙齿磨耗也重,接近老年个体.新安标本眶间部宽,面部凹陷,表现了明显的金丝猴(Rhinopithecus roxellanae)的特征.像新安这样完整的金丝猴颅骨,除四川万县盐井沟的一个未成年颅骨(R. roxellanae tingianus)外,在我国中原地区尚属首次发现.  相似文献   

14.
15.
《HOMO》2010,61(1):16-32
This article presents an approach for estimating the sexual dimorphism of adult crania using three-dimensional geometric morphometric methods. The study sample consisted of 139 crania of known sex (73 males and 66 females) belonging to persons who lived during the first half of the 20th century in Bohemia. The three-dimensional co-ordinates of 82 ecto-cranial landmarks and 39 semi-landmarks covering the midsagittal curve of the cranial vault were digitised using a MicroScribe G2X contact digitiser. The purposes of the investigation were to define the regions of the cranium where sexual dimorphism is most pronounced and to investigate the effectiveness of this method for determining sex from the shape of the cranium. The results demonstrate that it is better to analyse apportionable parts of the cranium rather than the cranium as a whole. Significant sexual differences (significance was determined using multivariate analysis of variance) were noted in the shape of the midsagittal curve of the vault, upper face, the region of the nose, orbits, and palate. No differences were recorded either in the shape of the cranium as a whole or in the regions of the base and the neurocranium. The greatest accuracy in determining sex was found in the region of the upper face (100% of study subjects correctly classified) and the midsagittal curve of the vault (99% of study subjects correctly classified).  相似文献   

16.
Among the numerous specimens presently classified withinDryopithecus africanus only one can be identified as a male of this species. Poor sampling is not the reason for the unequal numbers of male and female specimens. Rather, the males have been classified elsewhere, specifically withinDryopithecus nyanzae and Kenyapithecus africanus. The specimens to be transferred from these two taxa are proved to be males ofD. africanus. The newly transferred males are compared with the females to show the cranial dimorphism of the species.  相似文献   

17.
18.
The orangutan is widely recognized as a highly dimorphic species. An ontogenetic approach to the study of sexual dimorphism can assist researchers in understanding both where and when these differences develop. In this study, 357 orangutans from Borneo were divided into five developmental stages representing infancy to mature adulthood. Three-dimensional (3D) coordinate data from 16 landmarks representing the face and palate were analyzed by means of a Euclidean distance matrix analysis (EDMA), a quantitative method for the comparison of forms. Three separate analyses (an age-specific static comparison of forms, a sex-specific analysis of growth trajectories, and an intersex comparison of patterns of relative growth) were carried out with the intent to describe the rate, timing, magnitude, and pattern of growth in the orangutan face and palate. The results indicate that generally males and females share a similar, but not identical, pattern of growth or local form change, but differ in growth rate, timing, and magnitude of difference. Dimorphism in the face and palate can be localized in infancy and traced throughout all age intervals. Orangutan females grow slightly faster than males from infancy to adolescence, at which time male growth exceeds female growth. Female growth ceases with the advent of adulthood, while male growth continues (i.e., both the number and magnitude of the dimorphic dimensions increase). Males and females are similar in facial dimensions and growth related to the orbits, upper face, and palate width. They maintain these similarities throughout development. However, they differ in facial and nasal height, palate length, snout projection, depth of the nasopharynx, and hafting of the face onto the skull. The face broadens and the zygomatic bone flares dramatically in adult males, corresponding to the development of cheek pads. While growth patterns are similar between the two sexes, they differ in the lateral orbit, snout projection, and hafting of the face onto the cranium. Adult dimorphism is the result of growth patterns experienced throughout life, and it is not equally expressed across the cranium. An understanding of patterns of dimorphism, along with the magnitude of difference, may be helpful for interpreting dimorphism in the fossil record.  相似文献   

19.
The Lantian fossil hominid cranium from Southern Shensi Province, China, provides the earliest record of Homo erectus in northern east Asia, and is morphologically the most primitive specimen in the entire world. Importantly, the Kungwangling Lantian cranium (calvarium plus face), with associated stone tools in good geologic and paleontological context, is demonstrably both earlier and more primitive than the Choukoutien I remains. Faunal and palynological evidence support a mid-Mosbachium equivalent age (some 700,000 years). These facts are not recognized in the original Chinese reports. The Chenchiawo Lantian mandible, like the Choukoutien I remains, is attributable to the Holstein-equivalent in China (some 300,000 years ago), and therefore should no longer be temporally associated with the Kungwangling Lantian cranium. However, that the mandible may be morphologically associated with either calls attention to the relative independence of the mandible in human evolution. A comparative study of some modern Mongoloid populations in which very large mandibles may or may not be associated with a scaphoid keel or sagittal elevation depending upon the size and shape of the cranium demonstrates the relative autonomy of the mandible. Continuing selection pressure for a masticatory complex with large jaws provides another point of continuity between East Asian fossil and modern Mongoloid hunting populations such as Eskimos and Aleuts. A number of morphological features of the cranium, especially vault thickness, cranial capacity and reinforcement system, conform to expectation and confirm a general trend of reduction in vault thickness and reinforcement system with increase in cranial capacity over time within the single human species.  相似文献   

20.
Critical limb ischemia (CLI) is a severe obstruction of the arteries resulting from seriously decreased blood flow to the extremities, progressing to the point of pain and even skin ulcers or sores. CLI is associated with a high percentage of limb loss and mortality; however, no reliable biochemical indices are available to monitor the stages of CLI. We developed a strategy involving comparative proteomic analysis to detect CLI associated plasma biomarkers. 2D-DIGE and subsequent MALDI-TOF MS analyses provided 50 differentially expressed plasma proteins (including alkaline phosphatase and haptoglobin), between hemodialytic diabetic patients with and without CLI. Interestingly, more than half of the differentially expressed plasma proteins are associated with inflammatory responses. Our results show that CLI is strongly correlated to inflammation, indicating a strong potential for proteomics analysis in the diagnosis of CLI. To the best of our knowledge, this is the first report presenting a proteomics approach to monitor differentially expressed plasma proteins associated with CLI.  相似文献   

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