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1.
The orbital manifestations of Graves'' disease frequently constitute the major and distressing portion of the morbidity in this poorly understood process. Patients with optic neuropathy, exposure keratopathy or disfiguring proptosis may be aided considerably by decompression to permit swollen orbital contents to move into the maxillary and ethmoid sinus cavities. Experience with 38 patients treated over a five-year period indicates that antral-ethmoidal decompression is a logical, successful form of therapy and generally free of serious complications. it may provide benefit earlier in the course of Graves'' exophthalmopathy than has been accepted in the past.  相似文献   

2.
Although it is universally accepted that the Indridae family is monophyletic, there is no such unanimity about how the extant species of the Indrinae sub-family are related. Cranium and mandible disparity among Indri indri, Propithecus diadema, Propithecus verreauxi and Avahi laniger is analysed by geometrical morphometric methods and interpreted in adaptive terms. We compare results obtained by two techniques: Procrustes superimpositions for skulls and elliptical Fourier analysis for jawbones. In both studies, the three genera are clearly isolated. Avahi laniger is the species with the most paedomorphic cranium while Indri indri has the most 'juvenile' mandible. Cranial morphology is governed principally by orbit volume and body size, while jaw shape is related to diet (enlargement of the gonial region).  相似文献   

3.
We report the results of a census of Indri indri conducted in Betampona Nature Reserve, a lowland rain forest in eastern Madagascar. In addition, we conducted a year-long study of the ranging behavior of 3 groups in the southwestern region of the reserve. We used 2 methods to calculate population density and home range size, and to provide minimum and maximum estimates. Population density of Indri indri ranged from 6.9–13.2 individuals/km2 in Betampona. Mean home range size is 27 ha. The values for population density and home range size are intermediate between values for Indri indri in selectively logged and undisturbed montane rain forest. Our results suggest a relationship between habitat disturbance, population density and home range size for the species. Recent increases in habitat disturbance appear to cause an increase in population density and a decrease in home range size. The results are consistent with ones for other folivorous primate populations. Further research on habitat requirements of Indri and availability in Betampona is necessary to investigate the possibility of translocating Indri from nearby forest fragments into Betampona.  相似文献   

4.
We analyzed the dietary profiles and feeding behaviors of Propithecus diadema diadema and Indri indri in a community of animals that reside in midaltitude rain forest within Madagascar's Mantadia National Park. Propithecus diadema diadema ate a diverse mixture of fruits, seeds, flowers and young leaves, while the bulk of the diet of Indri indri consisted of young leaves, which resulted in significantly higher levels of fat and water-soluble carbohydrates in foods eaten by Propithecus diadema diadema. Fiber values of items eaten are high (54% NDF) for both species, though not significantly different between them. The preference for immature foliage by Indri indri suggests that their overall intake of fiber is greater than that of Propithecus diadema diadema, which had a high proportion of non-leaf material in their diet. We propose that differences in gut morphology between the two indriids contribute to their disparate diets. Levels of secondary compounds were high in certain food items, but overall they are also not significantly different between the two indriid diets. Propithecus diadema diadema exhibited a strong preference for 2 alkaloid-containing seed species, while no food of Indri indri contained alkaloids. In addition, Propithecus diadema diadema consumed a higher diversity of plant species on a daily/yearly basis, exhibited more feeding bouts on a daily basis, and their feeding bouts (on young leaves, fruit and flowers) are significantly shorter in duration than those of Indri indri. Furthermore, Propithecus diadema diadema had twice the number of geophagic episodes of Indri indri.  相似文献   

5.
Craniofacial osteomas are lesions of bone that most commonly occur in the paranasal sinuses. Characteristically they remain dormant or slowly enlarge but remain asymptomatic. The more rapidly expanding tumor types may extend to adjacent structures, but signs and symptoms of such involvement are rare before the third decade. Presented is a patient with an ethmoid osteoma associated with a 2-year history of progressive proptosis first noticed at age 14. The operative approach afforded through a transcoronal incision combines excellent surgical exposure with hidden scar.  相似文献   

6.
Anthropogenic habitat disturbance impairs ecosystem health by fragmenting forested areas, introducing environmental contamination, and reducing the quality of habitat resources. The effect of this disturbance on wildlife health is of particular concern in Madagascar, one of the world's biodiversity hotspots, where anthropogenic pressures on the environment remain high. Despite the conservation importance of threatened lemur populations in Madagascar, few data exist on the effects of anthropogenic disturbance on lemur health. To examine these impacts, indri (Indri indri) populations were evaluated from two forest reserves that differ in their exposure to anthropogenic disturbance. We compared the health status of 36 indri individuals from two sites: one population from a protected, undisturbed area of lowland evergreen humid forest and the other population from a reserve exposed to frequent tourism and forest degradation. Comparison of indri health parameters between sites suggests an impact of anthropogenic disturbance, including significant differences in leukocyte count and differential, 12 serum parameters, 6 trace minerals, and a higher diversity of parasites, with a significant difference in the presence of the louse, Trichophilopterus babakotophilus. These data suggest that indri living in disturbed forests may experience physiological changes and increased susceptibility to parasitism, which may ultimately impair reproductive success and survival.  相似文献   

7.
The development of the mesenchymal structures of the human orbit was studied using 10 mu or 60 mu serial sections of orbits of foetuses of 35 to 320 mm stages (C.R. length; 2-9 months). The ontogenesis of the orbital walls, the eye muscles, the blood vessels and the connective tissue was compared. This comparison revealed that the eye muscles and their fasciae together with the adventitial layers of the larger blood vessels and nerves develop first, closely linked in time to the progress of ossification and growth of most of the orbital bones. Only the (endochondral) ossification of the ethmoid starts much later. The orbital connective tissue septa development commences later, i.e. from the third month onwards, concurrently with the development of special mesenchymal condensations, a particular capillary system and adipose tissue. About five months later the adult configuration is attained.  相似文献   

8.
The diet and feeding behaviour of Indri indri were investigated in the Betampona Reserve, eastern Madagascar, over 12 months from February 2000 to February 2001. The highly folivorous diet of this species was confirmed--feeding on foliage (leaves and petioles) accounting for 82% of feeding records. Immature leaves were the preferred dietary item, but at times of relative scarcity mature leaves, fruit, seeds, flowers and bark were substituted. The indri were observed to feed on parts from 22 plant families, 37 genera and at least 42 species. The most important plant families in the diet of Indri were Lauraceae, Clusiaceae and Myristicaceae. Most feeding at Betampona was observed at 5-20 m above the forest floor amongst small (2.1-5.0 cm), oblique/horizontal supports (0-45 degrees). The indri spent 41.4% of their active period feeding most commonly in above-branch postures. Studies such as this are important for the development of conservation management plans for this endangered species.  相似文献   

9.
Exophthalmos may be due to an inflammatory process or to tumor formation. Inflammatory processes are most likely to occur in children and young adults. Tumors are the most common cause of exophthalmos in adults.Since the advent of chemotherapy and the antibiotics, rarely does orbital cellulitis develop from sinal infection.Tumors causing exophthalmos are likely to be benign if they arise from the frontal sinus and malignant if they arise from the maxillary and ethmoid sinuses.  相似文献   

10.
Exophthalmos may be due to an inflammatory process or to tumor formation. Inflammatory processes are most likely to occur in children and young adults. Tumors are the most common cause of exophthalmos in adults.Since the advent of chemotherapy and the antibiotics, rarely does orbital cellulitis develop from sinal infection. Tumors causing exophthalmos are likely to be benign if they arise from the frontal sinus and malignant if they arise from the maxillary and ethmoid sinuses.  相似文献   

11.
Uncertainties as to the nature and implications of osteoarthritis and calcium pyrophosphate deposition disease (CPPD) in primates were subject to critical review through examination of 153 prosimians and 1,250 Old World non-prosimian primates. Osteoarthritis, calcium pyrophosphate deposition disease, and infectious arthritis/osteomyelitis were relatively rare phenomena, affecting only 1.7% and 2.5%, respectively, of free-ranging prosimians and other Old World non-prosimian primates. Frequency of infection in Indri and Presbytis appears to reflect a unique susceptibility or exposure. Papio may have a unique predisposition to CPPD. The dichotomy (frequency and joint distribution) between free-ranging and artificially restrained animals suggests caution in interpretation of osteoarthritis or CPPD in non-free-ranging animals.  相似文献   

12.
The chondrocranium of the suckermouth armored catfish Ancistrus cf. triradiatus was studied. Its development is described based on specimens ranging from small prehatching stages with no cartilage visible, to larger posthatching stages where the chondrocranium is reducing. Cleared and stained specimens, as well as serial sections, revealed a cartilaginous skeleton with many features common for Siluriformes, yet several aspects of A. cf. triradiatus are not seen as such in other catfishes, or to a lesser extent. The skull is platybasic, but the acrochordal cartilage is very small and variably present, leaving the notochord protruding into the hypophyseal fenestra in the earlier stages. The ethmoid region is slender, with a rudimentary solum nasi. A lateral commissure and myodomes are present. The larger posterior myodome is roofed by a prootic bridge. The maxillary barbel is supported by a conspicuous cartilaginous rod from early prehatching stages. The ceratohyal has four prominent lateral processes. Infrapharyngobranchials I-II do not develop. During ontogeny, the skull lengthens, with an elongated ethmoid, pointing ventrally, and a long and bar-shaped hyosymplectic-pterygoquadrate plate. Meckel's cartilages point medially instead of rostrally.  相似文献   

13.
The cranial osteology and myology in the ateleopodiform Ateleopus japonicus were studied. Many free bony ossicles constitute the cephalic lateral line canals and are separated from the neurocranial roof by thick gelatinous tissue. The preoperculomandibular canal is unique in having a direct connection with the infraorbital canal owing to strong reduction in the size of the preoperculum. The neurocranium is largely cartilaginous, with 6 chondrocranial and 1 dermal element being absent (or not undergoing ossification). The left and right frontals are separated by a deep groove into which a long, mobile rostral cartilage is deeply inserted. Five pairs of cartilages, including 2 pairs of menisci, are associated with the ethmoid region, allowing premaxillary protrusion without involving maxillary rotation. The levator operculi is well developed and likely generates the primary force for depressing the lower jaw. The large interhyal is tightly attached to the entire ventral margin of the operculum, and the two elements appear to function as a single unit in mouth opening. The oral cavity is large because of the posterior position of the branchial arches [the last (5th) arch is situated below the 3rd vertebra]. In pelagic individuals the head is flat with a terminal mouth and straight parasphenoid shaft, whereas in small, benthopelagic individuals the head is rounded with an inferior mouth and bent parasphenoid shaft. “Bending” of the parasphenoid with a dorsally elevated apex is considered the result of the posterior migration of the mouth during the habitat shift. Ateleopodiform characters are discussed phylogenetically and the deep insertion of the rostral cartilage into an open space in the ethmoid region is suggested as a synapomorphy of the order and Lampridiformes.  相似文献   

14.
Nasofrontal dermoid sinus tracts that extend intracranially through the foramen cecum or ethmoid can be difficult to completely resect. Complete extirpation of nasofrontal dermoid sinus cysts is essential for effective treatment of this problem to minimize the chance of recurrence. The authors describe a new technique based on parasagittal osteotomies through the supraorbital bar, or bandeau, that ensures that the resection of the nasofrontal dermoid sinus cysts is complete. This technique also limits the size of the external nasal incision and enhances the surgeon's exposure of the anterior cranial base for resection of intradural extension. This approach also enhances exposure for the direct repair of the dura and the cranial vault.  相似文献   

15.
Twenty novel polymorphic microsatellite loci were isolated and characterized from the Indri, Indri indri, genome. Along with sequence data, this marker suite will be used in future studies to establish population structure throughout its range and to verify the proposed subspecific nomenclature. Gene diversity (0.760 and 0.783) and allelic richness (5.8 and 6.43) were estimated in the Betampona and Andasibe populations, respectively.  相似文献   

16.
Animal acoustic communication often takes the form of complex sequences, composed of multiple distinct acoustic units, which can vary in their degree of stereotypy. Studies of sequence variation may contribute to our understanding of the structural flexibility of primates' songs, which can provide essential ecological and behavioral information about variability at the individual, population, and specific level and provide insights into the mechanisms and drivers responsible for the evolutionary change of communicative traits. Several methods have been used for investigating different levels of structural information and sequence similarity in acoustic displays. We studied intra and interindividual variation in the song structuring of a singing primate, the indri (Indri indri), which inhabits the montane rain forests of Madagascar. Indri groups emit duets and choruses in which they combine long notes, short single units, and phrases consisting of a variable number of units (from two to six) with slightly descending frequency. Males' and females' contributions to the song differ in the temporal and frequency structure of song units and repertoire size. We calculated the similarity of phrase organization across different individual contributions using the Levenshtein distance, a logic distance that expressed the minimum cost to convert a sequence into another and can measure differences between two sequences of data. We then analyzed the degree of similarity within and between individuals and found that: (a) the phrase structure of songs varied between reproductive males and females: female structuring of the song showed a higher number of phrases if compared to males; (b) male contributions to the song were overall more similar to those of other males than were female contributions to the song of other females; (c) male contributions were more stereotyped than female contributions, which showed greater individual flexibility. The picture emerging from phrase combinatorics in the indris is in agreement with previous findings of rhythmic features and song repertoire size of the indris, which also suggested that female songs are potentially less stereotyped than those of males.  相似文献   

17.
A finite element model of the eye and the orbit was used to examine the hypothesis that the orbital fat provides an important mechanism of eye stability during head trauma. The model includes the globe, the orbital fat, the extra-ocular muscles, and the optic nerve. MRI images of an adult human orbit were used to generate an idealized geometry of the orbital space. The globe was approximated as a sphere 12 mm in radius. The optic nerve and the sclera were represented as thin shells, whereas the vitreous and the orbital fat were represented as nearly incompressible solids of low stiffness. The orbital bone was modelled as a rigid shell. Frontal head impact resulting from a fall onto a hard floor was simulated by prescribing to the orbital bone a triangular acceleration pulse of 200 g (1962 m/s(2)) peak for a duration of 4.5 ms. The results show that the fat provides the crucial passive mechanism of eye restraint. The mechanism is a consequence of the fact that the fat is incompressible and that its motion is restricted by the rigidity of the orbital walls. Thus, the acceleration loads of short duration cannot generate significant distortion of the fat. In contrast, the passive muscles provide little support to the globe. When the connection between the orbital fat and the eye is absent the eye is held mainly by the optic nerve. We discuss the possible role that this loss of contact may have in some cases of the evulsion of the eye and the optic nerve.  相似文献   

18.
A cribriform plate, a perpendicular plate, and two lateral masses are major components of the ethmoid bone of mammals. Notwithstanding the noticeable bone, virtually sitting in the center of the skull, extensive modifications of the skull of modern cetaceans, especially odontocetes (toothed whales), and the lack of clarity as to what characteristics delimit each element of the ethmoid has made the problem of the nature of the cetacean ethmoid more complicated and elusive than in other, less modified mammals. Furthermore, contention as to whether a perpendicular plate of the ethmoid, or the mesethmoid, exists in all mammals including cetaceans has remained unsettled. In odontocetes, the mesethmoid has been variably identified not only as the osseous nasal septum but also as the mediodorsal region of the posterior wall of the nasal passage below the nasals, as a mass of bone encased by the vomer in front of the osseous nasal cavity at the base of the rostrum, and as a combination of some portions mentioned above. The presence or absence of the mesethmoid in various groups of mammals has attracted the attention of some biologists, and here, I demonstrate that cetaceans have no mesethmoid. The close inspection of the ontogenetic changes of the basicranial elements in cetaceans reveals that a mass of bone ensheathed by the vomer in front, or at the level of the osseous nasal cavity is actually the presphenoid. It is highly likely that in odontocetes the posterior wall of the nasal passages below the nasals consists of the combination of the frontal, the imperforated cribriform plate, the paired ectethmoids, and the vomer, the latter three of which partially concealing the presphenoid dorsally and laterally as the ontogeny proceeds. In contrast, mysticetes clearly display ethmoturbinates and a cribriform plate, which are morphologically similar to those in terrestrial mammals. J. Morphol. 277:1661–1674, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

19.
Orbitozygomatic fractures are frequently encountered in plastic surgery. Management depends on a thorough preoperative physical examination, with attention to the ophthalmologic assessment. Coronal and axial computed tomography is essential for identifying fracture extent and orbital involvement. Adequate exposure and mobilization of fracture segments is essential for successful anatomical reduction. Failure to perform effective fixation may lead to subsequent complications, such as enophthalmos and diplopia. The authors illustrate the appropriate management of orbitozygomatic fractures in an effort to reduce complications and attain aesthetically satisfying results.  相似文献   

20.
Three novel heteroleptic Zn(II) complexes containing 8‐hydroxy quinoline and various pyrazolone‐based derivatives were synthesized and their structures confirmed by 1H–nuclear magnetic resonance, mass spectrometry, Fourier transform infra‐red spectroscopy, UV–vis analysis and element analysis. All three complexes showed good photoluminescence properties in the solid state and in solution in the maximum emission range from 475 to 490 nm with a quantum yield of 0.45 to 0.51. Absorption spectra revealed that the complexes possessed a maximum absorption range of 272–281 nm with a band gap of 2.59–2.68 eV. The highest occupied molecular orbital and lowest unoccupied molecular orbital of all the complexes were determine by cyclic voltammetry. All complexes displayed high thermal stability. These characteristics were assessed to find suitability for an alternative cheap light emitter for organic light‐emitting diodes.  相似文献   

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