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61.
The ontogenetic allometry of long bone proportions is poorly understood in Mammalia. It has previously been suggested that during mammalian ontogeny long bone proportions grow more slender (positive allometry; length ∝ circumference>1.0), although this conclusion was based upon data from a few small‐bodied taxa. It remains unknown how ontogenetic long bone allometry varies across Mammalia in terms of both taxonomy and body size. We collected long bone length and circumference data for ontogenetic samples of 22 species of mammals spanning six major clades and three orders of magnitude in body mass. Using reduced major axis bivariate regressions to compare bone length to circumference, we found that isometry and positive allometry are the most widespread patterns of growth across mammals. Negative allometry (i.e., bones growing more robust during ontogeny) occurs in mammals but is largely restricted to cetartiodactyls. Using regression slope as a proxy for long bone allometry, we compared long bone allometry to life history and organismal traits. Neonatal body mass, adult body mass, and growth rate have a negative relationship with long bone allometry. At an adult mass of roughly 15–20 kg, long bone growth shifts from positive allometry to mainly isometry and negative allometry. There were no significant relationships between ontogenetic long bone allometry and either cursoriality or basal metabolic rate. J. Morphol. © 2012 Wiley Periodicals, Inc.  相似文献   
62.
The rapid and direct delivery of a neuroactive endomorphin 1 derivative to the brain via nasal delivery is reported. A synthetic derivative of the native opioid peptide, endomorphin 1 bearing a lactose unit on the N-terminus of the peptide has been previously reported to exhibit antinoceceptive activity similar to morphine after both intravenous and oral administration. This compound has been administered nasally to rats and appeared in the olfactory bulb within 10 min of administration with negligible levels appearing in the circulating blood or in the rest of the brain. These results indicate that the peptide is absorbed into the brain via the olfactory epithelial pathway suggesting nasal delivery may be a viable alternative route of delivery in clinical applications.  相似文献   
63.
By means of immunohistochemistry and radioimmunoassay (RIA), we have investigated the possible occurrence of somatostatin (SOM)-like immunoreactivity (-LI) in the autonomic innervation of the pig nasal mucosa. SOM-immunoreactive (-IR) fibres were present around nasal arteries, arterioles and venous sinusoids. Double-labelling experiments revealed that SOM-LI was co-localized with the noradrenaline (NA) markers tyrosine hydroxylase and dopamine-β-hydroxylase as well as with neuropeptide Y (NPY) in a subpopulation of neurons in the superior cervical sympathetic ganglion and in perivascular nerve terminals. Furthermore, SOM-LI was also present in perivascular fibres containing vasoactive intestinal polypeptide (VIP) and NPY of presumably parasympathetic origin. The parasympathetic fibres that were associated with glands contained peptide histidine isoleucine (PHI), VIP and NPY but not SOM, suggesting that in the nasal mucosa SOM-IR is restricted to perivascular nerves. As revealed by RIA, the content of SOM-LI in biopsies of both nasal mucosa and superior cervical sympathetic ganglion was about 12 pmol/g and the reverse phase HPLC characterisation of SOM-LI shown two separate peaks for SOM-28 and SOM-14.  相似文献   
64.
目的:探讨慢性鼻-鼻窦炎患者鼻息肉组织中白介素-17(IL-17)、血管内皮生长因子(VEGF)的表达,并分析IL-17、VEGF表达水平的相关性。方法:以我院2015年1月~2017年12月期间收治的慢性鼻-鼻窦炎患者95例为研究对象,按患者有无鼻息肉分为伴鼻息肉(观察1组)49例和不伴鼻息肉(观察2组)46例。另选取同期在我院进行治疗的鼻中隔偏曲患者40例为对照组。所有患者均进行鼻内镜手术治疗,并在术中取其较窄侧的鼻甲黏膜作为检测标本,采用免疫组化SP法检测各组织标本中的IL-17、VEGF的表达水平,并分析IL-17、VEGF表达水平的相关性。结果:观察1组患者IL-17、VEGF的阳性表达率分别为93.88%(46/49)、85.71%(42/49),均高于观察2组患者IL-17、VEGF的阳性表达率[76.09%(35/46)、65.22%(30/46)]以及对照组患者IL-17、VEGF的阳性表达率[5.00%(2/40)、2.50%(1/40)],差异均具有统计学意义(P0.05)。观察1组患者IL-17、VEGF的表达水平分别为(38.92±5.34)个/LP、(33.21±4.87)个/LP,均高于观察2组患者IL-17、VEGF的表达水平[(28.19±4.56)个/LP、(21.28±4.03)个/LP]以及对照组患者IL-17、VEGF的表达水平[(9.31±2.76)个/LP、(7.19±1.95)个/LP],差异均具有统计学意义(P0.05)。经Spearman相关性分析结果显示,观察1组患者、观察2组患者中,IL-17与VEGF的表达水平呈正相关性(P0.05)。结论:慢性鼻-鼻窦炎患者鼻息肉组织中IL-17、VEGF的表达显著升高,且IL-17与VEGF表达水平呈明显的正相关性,表明IL-17、VEGF可能共同参与鼻息肉的发生与发展过程。  相似文献   
65.
目的:研究内镜揭盖术(ER)与唇齿沟径路切除术(LSPR)治疗鼻前庭囊肿(NVC)患者的临床疗效及对炎性因子的影响。方法:选择2015年7月至2017年6月来我院就诊的NVC患者106例,依据随机数字表法分别纳入ER组(53例)及LSPR组(53例)。ER组行ER治疗,LSPR组行唇齿沟径路切除术。观察两组术中出血量、手术时间、术后创口愈合时间、术后24 h疼痛评分及上皮化时间,两组术前、术后7 d白细胞介素-6(IL-6)、白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF-α)、C-反应蛋白(CRP)水平,两组术后并发症及复发情况。结果:ER组术中出血量、手术时间、术后创口愈合时间、术后24h疼痛评分及上皮化时间等手术指标均低于LSPR组,差异有统计学意义(P0.05);术后7 d,两组IL-6、IL-8、TNF-α及CRP水平均低于治疗前,且ER组低于LSPR组,差异有统计学意义(P0.05);ER组术后并发症发生率7.55%、术后复发率3.77%,均低于LSPR组的22.64%、20.75%,差异均有统计学意义(P0.05)。结论:与LSPR相比较,ER治疗NVC创伤小,恢复快,可有效降低术后炎性因子水平,术后并发症及复发率低,值得临床应用。  相似文献   
66.
67.
68.
目的:总结基于鼻翼软骨三脚架结构的改建技术在鼻尖综合整形术中的应用经验。方法:从2012年09月到2015年02月间,共84例求美者在我院进行初次鼻尖综合整形术。3例为男性,81例为女性。年龄20-45岁,平均年龄31.7岁。其中鼻头肥大伴鼻背低平65例,行鼻翼软骨缝合+鼻翼软骨切除+鼻假体+自体软骨帽状移植术;鼻头肥大、鼻背低平伴鼻小柱短小19例,行自体软骨鼻小柱支撑+鼻翼软骨切除+鼻翼软骨缝合+鼻假体植入+自体软骨帽状移植术。结果:84例求美者术后随访1个月-2年,除1例病例鼻头过于肥大,鼻尖形态改善不明显以外,其余求美者鼻额角及鼻尖角度及均较术前有明显改善,鼻小柱短小组的鼻小柱长度也较术前有明显改善。所有病例切口瘢痕均不明显,无明显并发症出现。结论:针对不同鼻翼软骨发育条件下的病人,个性化的应用鼻翼软骨三脚架结构改建的鼻尖综合整形术具有较好的临床效果,须根据不同病人特点选用。  相似文献   
69.
The form of the talus in some higher primates: a multivariate study   总被引:2,自引:0,他引:2  
Sixteen measurements of the talus have been taken on 334 tali of a total of eleven primate groups and several additional single individual specimens. Multivariate morphometric (canonical and generalized distance) analyses of these data in extant higher primates are presented and used to define the relative morphological positions of fossils of the genera Proconsul and Limnopithecus, of individual specimens from Kromdraai, Olduvai and Kiik-Koba (Homo neanderthalensis), and a group of specimens of Bronze Age man from Jericho. Following preliminary studies the ultimate analysis suggests that the various extant arboreal primates examined fall within an envelope that is defined by Macaca together with various other Old World monkeys and extending in different directions to the extreme genera (a) Pongo, (b) Hylobates and (c) Ateles. This separation is thus one which defines generally quadrupedal monkeys and separates the various extreme arboreal locomotor modes of (a) acrobatic climbing and hanging, (b) richochetal brachiation and (c) prehensile-tailed arm-swinging and hanging, respectively. Man and the African apes are well separated both from each other and from this spectrum of arboreally adapted genera. Bronze Age man from Jericho and Neandertal man from Kiik-Koba lie relatively close to the position for modern man although significantly separated from him. Limnopithecus, Proconsul, and the specimens from Kromdraai and Olduvai all lie within the envelope of arboreal species and specifically rather close to, although significantly different from, the orang-utan; they differ markedly from both man and the African apes. The possibility exists that the resemblances of Proconsul and Limnopithecus relate to arboreal habitus in these species. The findings for the specimens from Kromdraai and Olduvai suggest either that the morphological resemblances to arboreal forms relate to a previous arboreal history for these species, or that bipedality is much less advanced or uniquely different from that displayed by Homo. It is not inconceivable that both conditions might apply.  相似文献   
70.
Certain fossil foot bones (a terminal toe phalanx from Olduvai, specimens of tali from Spy, Skhūl, Olduvai, Kromdraai, Songhor and Rusinga) have been investigated by other workers using the multivariate statistical approach. The conclusions of their studies have, in the main, been based upon examination of early canonical variates alone. It is demonstrated here that if the full analyses (generalized distances) are taken into account, then almost exactly opposite conclusions obtain. The terminal toe phalanx from Olduvai is widely different from those of modern men; the Neandertal tali differ more from modern human bones than previously realized; the specimens from Olduvai, Kromdraai, Songhor and Rusinga are all completely dissimilar from both African ape and modern human tali.  相似文献   
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