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1.
P. Singh  R. Purkait 《HOMO》2009,60(5):461-472
Somatoscopy of the external ear provides a general idea of the shape of an ear, form of the helix, presence (or absence) of Darwin's tubercle and of the attachment of an ear lobe to a cheek, etc. It is of great importance not only to physical anthropologists but also to plastic surgeons, physicians and forensic scientists. There is no detailed somatoscopic study of the ear morphology concerning the entire Indian subcontinent. Hence, in the present study an attempt has been made to report the frequency of various somatoscopic features of various parts of the auricle of adult males and females who live in the central region of India.In both sexes oval-shaped ears and normally rolled helix were most common. The preauricular region was found to be clear with very few cases of the occurrence of pits and sinuses. Free lobules were more frequent among females than males but it was vice versa for Darwin's tubercle. The position of the ear's upper edge was most commonly located at the eyebrow tail while its lower edge was located at an upper lip level in both sexes. Hypoplastic lobules were noted in one-fifth of males but were very rare among females. Very few cases of lop ear, preauricular appendage and preauricular pit were observed.Some of these somatoscopic features act as soft biometric traits that improve the performance of the primary biometric system of personal identification. Somatoscopy of external ear acts as an aid to surgeons while reconstructing deformed ears and also helps physicians in detecting anomalies, for example, Edward's, cleft lip/cleft palate syndromes.  相似文献   

2.
Mechanically stimulating cell-seeded scaffolds by flow-perfusion is one approach utilized for developing clinically applicable bone graft substitutes. A key challenge is determining the magnitude of stimuli to apply that enhances cell differentiation but minimizes cell detachment from the scaffold. In this study, we employed a combined computational modeling and experimental approach to examine how the scaffold mean pore size influences cell attachment morphology and subsequently impacts upon cell deformation and detachment when subjected to fluid-flow. Cell detachment from osteoblast-seeded collagen-GAG scaffolds was evaluated experimentally across a range of scaffold pore sizes subjected to different flow rates and exposure times in a perfusion bioreactor. Cell detachment was found to be proportional to flow rate and inversely proportional to pore size. Using this data, a theoretical model was derived that accurately predicted cell detachment as a function of mean shear stress, mean pore size, and time. Computational modeling of cell deformation in response to fluid flow showed the percentage of cells exceeding a critical threshold of deformation correlated with cell detachment experimentally and the majority of these cells were of a bridging morphology (cells stretched across pores). These findings will help researchers optimize the mean pore size of scaffolds and perfusion bioreactor operating conditions to manage cell detachment when mechanically simulating cells via flow perfusion.  相似文献   

3.
Kidney fibrosis is one of the main pathological findings of progressive chronic kidney disease (CKD) although the pathogenesis of renal scar formation remains incompletely explained. Integrin-linked kinase (ILK), a major scaffold protein between the extracellular matrix (ECM) and intracellular signaling pathways, is involved in several pathophysiological processes during renal damage. However, ILK contribution in the CKD progress remains to be fully elucidated. In the present work, we studied 1) the renal functional and structural consequences of CKD genesis and progression when ILK is depleted and 2) the potential of ILK depletion as a therapeutic approach to delay CKD progression. We induced an experimental CKD model, based on an adenine-supplemented diet on adult wild-type (WT) and ILK-depleted mice, with a tubulointerstitial damage profile resembling that is observed in human CKD. The adenine diet induced in WT mice a progressive increase in plasma creatinine and urea concentrations. In the renal cortex it was also observed tubular damage, interstitial fibrosis and progressive increased ECM components, pro-inflammatory and chemo-attractant cytokines, EMT markers and TGF-β1 expressions. These observations were highly correlated to a simultaneous increase of ILK expression and activity. In adenine-fed transgenic ILK-depleted mice, all these changes were prevented. Additionally, we evaluated the potential role of ILK depletion to be applied after the disease induction, as an effective approach to interventions in human CKD subjects. In this scenario, two weeks after the establishment of adenine-induced CKD, ILK was abrogated in WT mice and stabilized renal damage, avoiding CKD progression. We propose ILK to be a potential target to delay renal disease progression.  相似文献   

4.
Summary Neurointermediate lobes from adult or 10-dayold rats were implanted by a stereotaxic procedure into the third ventricle of adult male rats, in an area close to the paraventricular nucleus. They were examined, using immunocytochemical and ultrastructural techniques, at times ranging from 1 week to 8 months. All grafts were recovered in a healthy condition although some rejection of the tissue was detected at the 1and 2-week stages. In the neural lobe, clusters of pituicytes were scattered among the loose network of capillaries, most of which had a fenestrated endothelium. The intermediate lobe remained organized in compact avascular lobules. Axons similar to those projecting into the neurointermediate lobe in situ, but also axons of other types (e.g., somatostatinergic, enkephalinergic) penetrated the grafts. Synapses with melanotrophic cells in the intermediate lobe and neurohaemal contacts in the neural lobe were frequent from 2 1/2 months after transplantation. Immunocytochemical and ultrastructural characteristics indicated intense secretory stimulation of the melanotrophic cells in the early stages. All cells enclosed in a same glandular lobule reacted in a similar manner. In later stages, when re-innervation occurred, the cells recovered their initial characteristics. The overall effect of the re-innervation of the intermediate lobe grafted in this location is inhibitory, as in the lobe in situ.  相似文献   

5.
The lower third of Asian faces is wider than that of Caucasians and it is determined by the size and width of the mandibular bone and the thickness of muscles and subcutaneous fat tissues surrounding it. Efforts to create an aesthetically slim and smooth facial contour line in nonobese people have led the authors to focus on two approaches: surgical resection of the masseteric muscle and modeling ostectomy of the square-angled mandibular bone. Because these procedures present some problems, the authors adopted a nonsurgical concept that chemically denervates muscles and reduces the bulk of the muscle. The authors have conducted a total of 1021 clinical cases from March of 2001 through September of 2002, in which patients were treated with botulinum toxin type A (Dysport; Ipsen Ltd, Slough, United Kingdom) for remodeling the lower facial contour line; 383 of those cases were followed up for at least 3 months after the initial injection. A database was made by measuring the change in the thickness of the injected muscle with an ultrasonogram. Eleven patients underwent resection of the mandibular angle before injection. The preinjection ostectomy group was involved in the study as a result of their dissatisfaction with the surgical results; they had a rather thick masseter muscle and not a bone problem. Some had both bone problems and a thick masseter muscle. Three months after the botulinum toxin injection, the thickness of the muscle was reduced by 31 percent on average. The atrophic effect of injection was observed after 2 to 4 weeks for most patients. Seventy percent of the 383 patients tracked were greatly satisfied with the result, with another 23 percent generally satisfied. No long-term side effects were reported. Masseteric hypertrophy is frequent in Asians because of racial characteristics and dietary habits. Botulinum toxin type A has made a new epoch in facial contouring for Asians. Considering that Asians have a prominent malar and a prominent mandible angle, the reduction in the thickness of the masseter can provoke relative prominence of the malar and mandible angle. Therefore, precise indication and anatomy of the facial muscle should be thoroughly understood, which will decrease the incidence of side effects and problems. Botulinum toxin type A (Dysport) injection is simple in technique, has few side effects, and promises a rapid return to daily life. The authors conclude that the injection of botulinum toxin type A can replace surgical masseter resection.  相似文献   

6.
淫羊藿属是分类学上研究的热点和难点,其类群发表和修订均较频繁。为更清晰掌握淫羊藿属的性状变异,该文在查阅该属研究成果和标本的基础上,结合课题组野外调查和分析,对该属重要性状进行系统梳理。花瓣式样是淫羊藿属分类的最重要依据,但并非绝对稳定,种内花瓣形态可能存在丰富变异。花瓣颜色、花药颜色,甚至花的大小至少在部分类群中不宜作为分类的主要依据。根茎性状在多数类群中不失为一个有用的分类性状,但不能一概而论,应基于广泛调查。多数类群的花茎上叶的类型及小叶存在不同程度的变异,在实际应用中存在一定困难。非腺毛特征十分复杂,不同样本存在不同程度差异,不宜作为物种鉴别的关键依据。淫羊藿属植物栽培后植株普遍更矮小,提示开展自然生境下的调查和形态观测对掌握物种形态特征非常必要。中国淫羊藿属类群仍处于活跃进化中,其形态变异复杂,物种鉴定和资源利用时应足够谨慎。  相似文献   

7.
We carried out SEM studies of the wing-coupling apparatus (WCA) of 33 species of Auchenorrhyncha (Homoptera) belonging to 15 families. The main structure of this apparatus always has a wing-coupling forefold (WCFF) on the claval margin of the mesothoracic wings and a similar, longitudinal wing-coupling hindfold (WCHF) or shorter wing-coupling lobe (WCL) or wing-coupling hook (WCH) on the costal margin of the metathoracic wings. We believe that the differences in the morphology of the microsculptures present on the various parts of the WCA (in addition to the shape and size of the WCFF, WCHF, WCL and WCH) may be used as systematic characteristics at least up to the generic level.  相似文献   

8.
9.
Differences in morphology among species are proximately caused by changes in the ontogeny of individuals. It is therefore of importance to analyse possible differences in growth parameters among closely related species in order to understand what parameters are most and least likely, respectively, to change in evolution. In this paper I analyse growth in two closely related sympatric species, namely Great tit, Parus major, and Blue tit, P. caeruleus. The former is considerably larger than the latter in all external traits. The growth rates of the two species were found to be very similar for all traits, thus excluding differences in growth rate as a potential cause of evolutionary size changes. Offset of growth occurred at relatively similar times in the two species, excluding this factor as a major cause of the final size differences. However, size differences at hatching were pronounced and remained so throughout ontogeny, pointing to initial size (egg size or hatching size) as the target of factors promoting change. Bivariate allometric relations of traits vs. body size (mass) were similar between the two species at all ontogenetic stages. There was a high correlation among traits especially at intermediate age stages (5 and 8 days), but these correlations became weaker at older age and approached the low pattern of integration found in adults. All this suggests the operation of a general growth factor affecting all parts of the phenotype simultaneously, which has its major influence at the time of maximal growth. If closely related species in general have highly similar growth patterns, strong evolutionary allometry as found in many avian taxa is to be expected.  相似文献   

10.
B Guyuron 《Plastic and reconstructive surgery》1992,90(5):830-7; discussion 838-40
Despite significant attention to the cervical region over the last two decades, the hyoid bone has not received deserved recognition. In this report, the anatomy and role of the hyoid bone and suprahyoid muscles in cervicomental morphology are reviewed. From an analysis of cephaloxerograms on 54 patients, it was concluded that on a balanced neck, the most caudal border of the hyoid body is located at or above a line parallel to the Frankfort horizontal line passing through the most caudal border of the mandibular symphysis (menton). Of the muscles that control the position of the hyoid bone, the anterior belly of the diagastric, geniohyoid, and mylohyoid muscles pull the hyoid bone cephalad and anteriorly. The stylohyoid muscles, on the other hand, pull this bone cephalad and posteriorly, while the sternohyoid and omohyoid muscles pull it caudally. Transection of the first three muscles at their attachment to the posterior aspect of the mandible in patients with dysmorphic necks due to caudal and anterior hyoid position will allow posterior and cephalad relocation of this bone, which improves the neck contour. Sixteen patients, with an average follow-up of 27 months, have undergone this procedure, with cervicomental contour improvement in all cases. The degree of improvement ranged from 1 to 5 (5 being excellent): One patient was ranked 1, two patients were ranked 2, two patients were ranked 3, and the rest were ranked 4 or 5. One patient had overcorrection as a result of an aggressive concomitant submental lipectomy. Another patient had central depression in the submental area. None of the patients had difficulties with mandibular movement or swallowing.  相似文献   

11.
The incidence of adhesion of Pasteuria penetrans endospores to Meloidogyne incognita second-stage juveniles (J2) was studied after pretreatment of the latter with monoclonal antibodies (MAb), cationized ferritin, and other organic molecules in replicated trials. Monoclonal antibodies developed to a cuticular epitope of M. incognita second-stage juveniles gave significant reductions in attachment of P. penetrans endospores to treated nematodes. MAb bound to the entire length of J2 except for the area of the lateral field, where binding was restricted to the incisures. Since reductions in attachment with MAb treatment were modest, it is uncertain if these results implicated a specific surface protein as a factor that interacted in binding of the endospore to the nematode cuticle. Endospore attachment was decreased following treatment of the nematode with the detergents sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB). Endospore attachment to live nematodes was significantly greater than attachment to dead nematodes. Attachment rates of three P. penetrans isolates to M. incognita race 3 varied between isolates. The effects of neuraminidase, pronase, pepsin, trypsin, lipase, and Na periodate on endospore attachment were inconsistent. The cationic dye alcian blue, which binds sulfate and carboxyl groups on acidic glycans, had no consistent effect on endospore attachment. The incidence of endospore attachment was significantly lower but modest, at best, for nematodes that were treated with cationized ferritin alone or cationized ferritin following monoclonal antibody. The lack of consistency or extreme reduction in most experiments suggests that attachment of P. penetrans spores to M. incognita is not specified by only one physico-chemical factor, but may involve a combination of at least two physico-chemical factors (including surface charge and movement of the J2). This points to a need for analysis of combined or factorial treatment effects.  相似文献   

12.
13.
Hydrogen is a potential sustainable energy source and it could become an alternative to fossil fuel combustion, thus helping to reduce greenhouse gas emissions. The biological production of hydrogen, instead of its chemical synthesis, is a promising possibility since this process requires less energy and is more sustainable and eco-friendly. Several microorganisms have been used for this purpose, but Escherichia coli is one of the most widely used in this field. The literature in this area has increased exponentially in the last 10 years and several strategies have been reported in an effort to improve hydrogen production. In this work, the stay of the art of hydrogen biosynthesis by E. coli and metabolic engineering strategies to enhance hydrogen production are reviewed. This work includes a discussion about the hydrogenase complexes responsible for the hydrogen synthesis in this microorganism and the central carbon metabolism pathways connected to this process. The main metabolic engineering strategies applied are discussed, including heterologous gene expression, adaptive evolution and metabolic and protein engineering. On the other hand, culture conditions, including the use of carbon sources such as glycerol, glucose or organic wastes, have also been considered. Yields and productivities of the most relevant engineered strains reported using several carbon sources are also compared.  相似文献   

14.
In this study, the demography of the common demosponge Ircinia felix was examined at Tamarindo, a coral reef located in the island municipality of Culebra, Puerto Rico. A preliminary study comparing the size structure of two subpopulations within the reef, Tamarindo Norte (TN) and Tamarindo Sur (TS), indicated that sponges at TN are significantly larger than sponges at TS. This result served as a baseline for the present comparative study in which we aimed to determine whether the spatial differences in population size structure can be explained either by a difference in rates of survival, growth, or recruitment, or a combination of these. To accomplish our goal, we followed the growth, survival and recruitment of I. felix at the two localities for one year. Growth was the only demographic parameter that differed significantly between localities. Because the most obvious distinction between the study sites was the absence of the octocoral Gorgonia ventalina at TS, we hypothesized that the faster overall growth rate of sponges at TN was related to the presence of the octocoral. To test this hypothesis, we compared growth rates between sponges associated with the octocoral and those individuals not associated. We found that sponges growing near G. ventalina grew significantly faster than non-associated sponges. This result suggests that the octocoral facilitates the growth of I. felix and therefore may account, at least in part, for the spatial differences in population size structure.  相似文献   

15.
Microhabitat characteristics are expected to influence the distribution of stream fish species at fine spatial scales (e.g., within riffle segments). Body size is probably the most important trait that constrains microhabitat occupation by fish, but the effect of intraspecific variation has been understudied. We investigated how physical microhabitat characteristics affect species and body size distribution of fish within a stream riffle segment in a coastal subtropical drainage of Brazil. Fishes were sampled by electrofishing 56 riffle plots along a 730-m long stream segment. Species composition was significantly related to four microhabitat characteristics: substrate size, flow velocity, distance to margin and depth. In addition, mean body size increased with increasing substrate size and depth of microhabitat sampling plots. However, when including species identity in linear mixed-effects models (LMM), we observed a different relationship between body size and microhabitat characteristics, but most of the variation was explained by species identity. Thus, we fitted LMMs separately for each species and found species-specific relations between intraspecific variation in body size and microhabitat characteristics. The low variation explained in the models suggests that other fine scale factors, such as biotic interactions and dispersal from adjacent habitat patches, should be incorporated in modeling microhabitat use by stream fish. Our findings suggest that body size is important by itself, but intraspecific variation in body size also constrains microhabitat use differently for each species, which may depend on other species-specific traits, such as morphology, behavior and life history.  相似文献   

16.
The surface morphology of Entamoeba histolytica trophozoites of HM 1:IMSS (axenic and monoxenic) and HK9 (axenic) strains cultured on plastic and MDCK cell substrates was examined using scanning electron microscopy (SEM). The conditions for processing trophozoites were determined by comparing the SEM observations with the morphology of living amebas examined by light microscopy. The most frequent surface differentiations in all the amebas observed with SEM were lobopodia. Round cytoplasmic projections were found in approximately half of the axenic amebas. Endocytic stomas and filopodia were more common in monoxenic cultures while the uroid was found in only 2-8% of all examined amebas. The basal surfaces of the trophozoites, involved in both attachment and cytolysis, showed no unusual features, except for the presence of a small number of short filopodia at the outer edge. No differences were found in the morphology of amebas grown on artificial and natural substrates. These observations demonstrate that there are significant quantitative differences in the surface morphology of cultured trophozoites of different strains of E. histolytica and that association with bacteria produces an increase in the relative number of surface specializations of the parasite.  相似文献   

17.

Purpose

Short Tandem Repeat (STR) genetic markers hold great potential in forensic investigations, molecular diagnostics and molecular genetics research. AmpFlSTR® Identifiler™ PCR amplification kit is a multiplex system for co-amplification of 15 STR markers used worldwide in forensic investigations. This study attempts to assess forensic validity of these STRs in Pakistani population and to investigate its applicability in quick and simultaneous diagnosis and tracing parental source of common chromosomal aneuploidies.

Methodology

Samples from 554 healthy Pakistani individuals from 5 different ethnicities were analyzed for forensic parameters using Identifiler STRs and 74 patients' samples with different aneuploidies were evaluated for diagnostic strengths of these markers.

Results

All STRs hold sufficient forensic applicability in Pakistani population with paternity index between 1.5 and 3.5, polymorphic information content from 0.63 to 0.87 and discrimination power ≥ 0.9 (except TPOX locus). Variation from Hardy–Weinberg equilibrium was observed at some loci reflecting selective breeding and intermarriages trend in Pakistan. Among aneuploidic samples, all trisomies were precisely detectable while aneuploidies involving sex chromosomes or missing chromosomes were not clearly detectable using Identifiler STRs. Parental origin of aneuploidy was traceable in 92.54% patients.

Conclusion

The studied STR markers are valuable tools for forensic application in Pakistan and utilizable for quick and simultaneous identification of some common trisomic conditions. Adding more sex chromosome specific STR markers can immensely increase the diagnostic and forensic potential of this system.  相似文献   

18.
Three-dimensional morphology of the human embryo typically is visualized through computerized modeling techniques utilizing planar contours as the data base. Through this approach, tissue outlines are digitized, and contour lines are superimposed, providing a depth perspective. However, these techniques represent embryonic tissues as discontinuous surfaces and therefore ignore morphological information between sections. The purpose of this study was to develop a computerized routine for the three-dimensional surface modeling of craniofacial morphology in human embryos. Tissue outlines are digitized, thus converting contour information into x,y,z coordinate data. The three-dimensional reconstruction program BCSURF opens the data file and plots each tissue polygon. A center is determined for each contour, and this value is used to divide each polygon into four segments. Surface patches are generated by mapping each segment onto the corresponding segment of subsequent sections. A face table is constructed representing the surface patches and plane normals are generated for each patch. The normal and depth values are appended to the face table, and these measures determine the color intensity for each patch. Finally, patches are plotted providing a polygon mesh model, and each patch is filled with a dither pattern according to shading values. Three-dimensional reconstructions of the craniofacial region in Carnegie embryos (stages 15-17) are generated, and major morphological features are observed. Although bilevel shading capabilities cause discontinuous shading textures, this simple and inexpensive system can be easily upgraded for high-resolution graphics.  相似文献   

19.
Pneumocystis carinii is the most important opportunistic pathogen of humans in the world. Pneumocystis carinii is experimentally detected in the lungs of rats, mice, rabbits, and monkeys, however, the organisms from different mammals are identical in microscopic morphology. The present study tried to find out more mammalian hosts of P. carinii and also to differentiate the organisms from different mammals by karyotyping. Rats, mice, hamsters, rabbits, cats, and dogs were successfully infected by P. carinii, but guinea pigs and pigs were not. Karyotype of P. carinii from rabbits showed similar size range of chromosomes with that of the prototype, but in different pattern. The patterns from cats and dogs were also different from that of rats. The present study confirms that cats and dogs are infected by P. carinii and at least total three karyotype strains of P. carinii are proven in Korea.  相似文献   

20.
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