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The nasal capsules of anurans are formed by an intricate set of sac-like cavities that house the olfactory organ and constitute the beginning of the respiratory system. In tadpoles, nasal capsules do not have a respiratory function, but each is composed of a single soft tissue cavity lined with olfactory epithelium. Our study has revealed that in Spea the nasal cartilages and septomaxillae are de novo adult structures that form dorsal to the larval skeleton of the ethmoid region. The only element of the adult nasal capsule that is partially derived from the larval skeleton is the solum nasi. Development of the nasal skeleton begins at about Gosner Stage 31, with chondrification of the septum nasi and lamina orbitonasalis. The alary cartilage and superior prenasal cartilage are the first of the anterior nasal cartilages to chondrify at Gosner Stage 37. By Gosner Stages 40/41, the ethmoid region is composed of the larval structures ventrally and the adult structures dorsally. By Stage 44, the larval structures have eroded. The adult nasal capsule is characterized by: (1) a septum nasi that projects ventrally beyond the plane of the nasal floor; (2) a paranasal commissure that forms the ventral margin of the fenestra nasolateralis; and (3) a large skeletal support for the eminentia olfactoria formed by the nasal floor and vomer. The timing of chondrification of the anterior nasal cartilages and the development of the postnasal wall, inferior prenasal cartilage, fenestra nasolateralis, and paranasal commissure are discussed and compared with those of other anuran species. This study also includes a discussion of the morphology of the skeletal support for the eminentia olfactoria, a structure best developed in distinctly ground-dwelling frogs such as spadefoot toads. Finally, we propose a more precise restriction of the terminology that is used to designate the posterior structures of the olfactory region of anurans. 相似文献
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López-Cano M Rodríguez-Navarro J Rodríguez-Baeza A Armengol-Carrasco M Susín A 《Computers in biology and medicine》2007,37(9):1321-1326
A suitable dynamic 3D model that allows the simulation of the inguinal region with real-time performance on a personal computer was developed. A geometric model adjusted to real data was created by means of semiautomatic contour segmentation of anatomic units from the visible human project and data generated from classical anatomic information. A dynamic model included converting muscular units from their continuous geometric representation into a set of voxels and then real-time interaction and performance. The current implementation enables deformation of the realistic model associated with pushing and stretching interaction, allowing immersion in the anatomy of the inguinal structures. The model does not allow simulation of surgical interventions. 相似文献
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Rodriguez-Tudela JL Gomez-Lopez A Alastruey-Izquierdo A Mellado E Bernal-Martinez L Cuenca-Estrella M 《Diagnostic microbiology and infectious disease》2007,58(4):435-440
The sequence polymorphisms of intergenic transcribed spacer and the antifungal susceptibility profile of 18 Trichosporon asahii isolates from Spain, Argentina, and Brazil together with 43 intergenic transcribed spacer 1 sequences deposited in the GenBank were analyzed. Six genotypes were detected instead of 5 genotypes described previously. Genotype 1 was the most common found comprising 57.3% of all strains, followed by genotype 3 (14.7%) and genotype 5 (13.1%). Spanish strains had members in all genotypes except 2, whereas South American isolates were grouped with genotypes 1, 3, and 6. Our results indicate that all genotypes are present in at least 2 countries suggesting a worldwide distribution. On the other hand, genotype 6 was not previously described but was only composed of 2 South American strains isolated from a subcutaneous abscess and skin. All isolates showed amphotericin B MICs>or=2 mg/L supporting the in vitro resistance of this species to this antifungal. Three isolates from South America showed high MICs to all antifungals analyzed. The true epidemiologic usefulness of classifying T. asahii in genotypes should be ascertaining analyzing a high number of isolates from many countries. 相似文献
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李群 《临床合理用药杂志》2014,(10):10-11
目的分析彝族地区小儿结核性脑膜炎的临床特征,探讨早期诊断的有效方法,减少误诊。方法回顾性分析2010年1月-2012年12月我院71例临床诊断结核性脑膜炎的住院患儿病例资料。结果农村彝族患病率高,占全组病例90.1%,全组病例仅4例有明确卡介苗接种史。全组患儿主要临床表现为:发热,神经系统症状颅内压增高和脑膜刺激征。胸部X线片或胸部cT异常31例(47.0%),其中粟粒型结核6例(19.4%)。全组69例行头部CT,42例异常,阳性率为60.9%,其中33例伴随脑积水改变(46.5%)。结论发热伴颅内压增高,脑神经损害是小儿结核性脑膜炎常见的表现。彝族地区卡介疫苗接种覆盖率低,发病率高,应重视宣传及加强对基层的防疫工作。头颅CT是结核性脑膜炎早期诊断和判断预后比较有效的方法。对疑诊患者或脑脊液不典型患者应早期行头部CT及胸部X线片检查。 相似文献
129.
To date, there is a dearth of information on canine parvovirus-2 (CPV-2) from the Caribbean region. During August–October 2020, the veterinary clinic on the Caribbean island of Nevis reported 64 household dogs with CPV-2-like clinical signs (hemorrhagic/non-hemorrhagic diarrhea and vomiting), of which 27 animals died. Rectal swabs/fecal samples were obtained from 43 dogs. A total of 39 of the 43 dogs tested positive for CPV-2 antigen and/or DNA, while 4 samples, negative for CPV-2 antigen, were not available for PCR. Among the 21 untested dogs, 15 had CPV-2 positive littermates. Analysis of the complete VP2 sequences of 32 strains identified new CPV-2a (CPV-2a with Ser297Ala in VP2) as the predominant CPV-2 on Nevis Island. Two nonsynonymous mutations, one rare (Asp373Asn) and the other uncommon (Ala262Thr), were observed in a few VP2 sequences. It was intriguing that new CPV-2a was associated with an outbreak of gastroenteritis on Nevis while found at low frequencies in sporadic cases of diarrhea on the neighboring island of St. Kitts. The nearly complete CPV-2 genomes (4 CPV-2 strains from St. Kitts and Nevis (SKN)) were reported for the first time from the Caribbean region. Eleven substitutions were found among the SKN genomes, which included nine synonymous substitutions, five of which have been rarely reported, and the two nonsynonymous substitutions. Phylogenetically, the SKN CPV-2 sequences formed a distinct cluster, with CPV-2b/USA/1998 strains constituting the nearest cluster. Our findings suggested that new CPV-2a is endemic in the region, with the potential to cause severe outbreaks, warranting further studies across the Caribbean Islands. Analysis of the SKN CPV-2 genomes corroborated the hypothesis that recurrent parallel evolution and reversion might play important roles in the evolution of CPV-2. 相似文献
130.
Firas Mourad James Dunning Andrea Zingoni Raffaele Iorio Raymond Butts Noah Zacharko César Fernández-de-las-Peñas 《Journal of manipulative and physiological therapeutics》2019,42(1):12-22
ObjectiveThe purpose of this study was to determine from which side of the spine the popping sound (PS) emanates during side-lying, rotatory high-velocity low-amplitude (HVLA) thrust manipulation directed to the L5-S1 articulation using a time-frequency analysis. Secondary aims were to calculate the average number of PSs, the duration of lumbar thrust manipulation, and the duration of a single PS.MethodsThirty-four asymptomatic participants received 2 lumbar HVLA thrust manipulations targeting the right and left L5-S1 articulations. Two high sampling rate accelerometers were secured bilaterally 25 mm lateral to the midline of the L5-S1 interspace. For each manipulation, 2 audio signals were extracted and singularly processed via spectrogram calculation to obtain the release of energy over time on each side of the lumbosacral junction.ResultsDuring 60 HVLA thrust manipulations, it was measured a total of 320 PSs. Of those PSs, 176 occurred ipsilateral and 144 occurred contralateral to the targeted L5-S1 articulation; that is, the PS was no more likely to occur on the upside than the downside facet after right or left rotatory L5-S1 HVLA thrust manipulation. Moreover, PSs occurring on both sides at the same time were detected very rarely (ie, 2% of cases) with the lumbar HVLA thrust manipulations. The mean number of audible PSs per lumbosacral HVLA thrust manipulation was 5.27 (range 2-9). The mean duration of a single manipulation was 139.13 milliseconds (95% confidence interval: 5.61-493.79), and the mean duration of a single PS was 2.69 milliseconds (95% confidence interval: 0.95-4.59).ConclusionBased on our findings, spinal manipulative therapy practitioners should expect multiple PSs that most often occur on the upside or the downside facet articulations when performing HVLA thrust manipulation to the lumbosacral junction (ie, L5-S1). However, whether the multiple PSs found in this study emanated from the same joint or adjacent ipsilateral or contralateral facet joints remains unknown. A single model may not necessarily be able to explain all of the audible sounds during HVLA thrust manipulation. 相似文献