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51.
The main aim of the present work is to synthesize the information obtained from our dissections of the pectoral and forelimb muscles of representative members of the major extant taxa of limbed amphibians and reptiles and from our review of the literature, in order to provide an account of the comparative anatomy, homologies and evolution of these muscles in the Tetrapoda. The pectoral and forelimb musculature of all these major taxa conform to a general pattern that seems to have been acquired very early in the evolutionary history of tetrapods. Although some muscles are missing in certain taxa, and a clear departure from this general pattern is obviously present in derived groups such as birds, the same overall configuration is easily distinguishable in these taxa. Among the most notable anatomical differences between the groups, one that seems to have relevant evolutionary and functional implications, concerns the distal insertion points of the forearm musculature. In tetrapods, the muscles of the radial and ulnar complexes of the forearm are pleisomorphically mainly inserted onto the radius/ulna or onto the more proximal carpal bones, but in mammals some of these muscles insert more distally onto bones such as the metacarpals. Interestingly, a similar trend towards a more distal insertion of these muscles is also found in some non‐mammalian tetrapod taxa, such as some anurans (e.g. Phyllomedusa). This may be correlated with the acquisition of more subtle digital movement abilities in these latter taxa. 相似文献
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53.
The Anatomy and Ontogeny of the Head,Neck, Pectoral,and Upper Limb Muscles of Lemur catta and Propithecus coquereli (Primates): Discussion on the Parallelism Between Ontogeny and Phylogeny and Implications for Evolutionary and Developmental Biology 下载免费PDF全文
Rui Diogo Julia L. Molnar Timothy D. Smith 《Anatomical record (Hoboken, N.J. : 2007)》2014,297(8):1435-1453
54.
Bernardes A Dionísio J Diogo D Coelho P Patrício J 《Surgical and radiologic anatomy : SRA》2005,27(2):79-85
Intraoperative hemostatic suture to treat a bleeding duodenal ulcer is sometimes difficult when there is massive hemorrhage. The aims of this paper are: (1) to describe a practical and easy intraoperative procedure which quickly decreases a massively bleeding duodenal ulcer, allowing the surgeon to identify the bleeding site clearly and obtain definitive hemostasis by suturing the involved vessels with a low risk of common bile duct lesion; and (2) to study in cadavers the anatomical basis of this surgical procedure already successfully performed on patients. Fourteen patients with massive duodenal ulcer bleeding, after unsuccessful endoscopic hemostasis, were operated on and included in this study. After surgical anterior gastroduodenotomy, the surgeon introduced a finger in a downward and forward direction in the bursa omentalis vestibule through the omental foramen. This simple and quick procedure decreased hemorrhage by compressing the gastroduodenal artery against the first part of the posterior surface of the duodenum. Twenty-four fresh blocks of normal tissue were removed from cadavers and were injected with silicone rubber through the common hepatic artery. The distance between the gastroduodenal artery and the omental foramen was measured. With this maneuver the surgeon can clearly see the exact bleeding site and perform an adequate suture with a minor risk of common bile duct lesion. 相似文献
55.
Vilarinho L Cardoso ML Gaspar P Barbot C Azevedo L Diogo L Santos M Carrilho I Fineza I Kok F Chorão R Alegria P Martins E Teixeira J Cabral Fernandes H Verhoeven NM Salomons GS Santorelli FM Cabral P Amorim A Jakobs C 《Human mutation》2005,26(4):395-396
We studied 21 patients, from 18 families, with L-2-hydroxyglutaric aciduria (L-2-HGA), a rare neurometabolic disorder with a homogeneous presentation: progressive neurodegeneration with extrapyramidal and cerebellar signs, seizures, and subcortical leukoencephalopathy. Increased levels of L-2-hydroxyglutaric acid in body fluids proved the diagnosis of L-2-HGA in all 21 patients. We analyzed the L-2-HGA gene (L2HGDH), recently found to be mutated in consanguineous families with L-2-HGA, and identified seven novel mutations in 15 families. Three mutations appeared to be particularly prevalent in this Portuguese panel: a frameshift mutation (c.529delC) was detected in 12 out of 30 mutant alleles (40%), a nonsense mutation (c.208C>T; p.Arg70X) in 7/30 alleles (23%), and a missense mutation (c.293A>G; p.His98Arg) in four out of 30 mutant alleles (13%), suggesting that common origin may exist. Furthermore, two novel missense (c.169G>A; p.Gly57Arg, c.1301A>C; p.His434Pro) and two splice error (c.257-2A>G, c.907-2A>G) mutations were found. All the mutations presumably lead to loss-of-function with no relationship between clinical signs, progression of the disease, levels of L-2-HGA and site of the mutation. In the three remaining families, no pathogenic mutations in the L-2-HGA were found, which suggests either alterations in regulatory regions of the gene or of its intervening sequences, compound heterozygosity for large genomic deletion and, or further genetic heterogeneity. 相似文献
56.
Paula Pinto Cristina Costa-Santos Diogo Ayres-de-Campos 《The journal of maternal-fetal & neonatal medicine》2016,29(9):1440-1444
Objective: To assess combined maternal (MHR) and fetal heart rate (FHR) recordings during labor, in relation with maternal–fetal attachment and prediction of newborn acidemia.Study design: Fifty-nine simultaneous MHR and FHR recordings were acquired in the final minutes of labor. Computer analysis followed the FIGO guidelines with estimation of MHR and FHR baselines, accelerations, decelerations, short- (STV) and long-term variabilities. MHR and FHR characteristics, their differences and correlations were assessed in relation to labor progression and to newborn umbilical artery blood (UAB) pH lower than 7.15 and 7.20. To assess prediction of acidemia, areas under ROC curves (auROC) were calculated.Results: Progression of labor was associated with a significant increase in MHR accelerations and FHR decelerations both in the non-acidemic and acidemic fetuses (p?<?0.01). At the same time there was an increase in MHR–FHR correlations and differences in accelerations and decelerations in acidemic fetuses. The auROC ranged between 0.50 for FHR accelerations and 0.77 for MHR baseline plus FHR STV.Conclusions: MHR and FHR respond differently during labor with signs of increased maternal–fetal attachment during labor progression in acidemic fetuses. Combined MHR–FHR analysis may help to improve prediction of newborn acidemia compared with FHR analysis alone. 相似文献
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Thomazi AP Godinho GF Rodrigues JM Schwalm FD Frizzo ME Moriguchi E Souza DO Wofchuk ST 《Mechanisms of ageing and development》2004,125(7):475-481
The excitotoxicity of the neurotransmitter glutamate has been shown to be connected with many acute and chronic diseases of the CNS. High affinity sodium-dependent glutamate transporters play a key role in maintaining adequate levels of extracellular glutamate. In the present study, we used slices of striatum, hippocampus and cortex from rat brain to describe the in vitro profile of glutamate uptake during development and ageing, and its sensitivity to guanosine. In all structures, glutamate uptake was higher in immature animals. There was a maximum decrease in glutamate uptake in striatum and hippocampus in 15-month-old rats, which later increased, while in cortex there was a significant decrease in rats aged 60 days old. The effect of guanosine seems to be age and structure dependent since the increase in basal glutamate uptake was only seen in slices of cortex from 10-day-old animals. 相似文献
59.
McManus BA Coleman DC Moran G Pinjon E Diogo D Bougnoux ME Borecká-Melkusova S Bujdákova H Murphy P d'Enfert C Sullivan DJ 《Journal of clinical microbiology》2008,46(2):652-664
The pathogenic yeast Candida dubliniensis is phylogenetically very closely related to Candida albicans, and both species share many phenotypic and genetic characteristics. DNA fingerprinting using the species-specific probe Cd25 and sequence analysis of the internal transcribed spacer (ITS) region of the ribosomal gene cluster previously showed that C. dubliniensis is comprised of three major clades comprising four distinct ITS genotypes. Multilocus sequence typing (MLST) has been shown to be very useful for investigating the epidemiology and population biology of C. albicans and has identified many distinct major and minor clades. In the present study, we used MLST to investigate the population structure of C. dubliniensis for the first time. Combinations of 10 loci previously tested for MLST analysis of C. albicans were assessed for their discriminatory ability with 50 epidemiologically unrelated C. dubliniensis isolates from diverse geographic locations, including representative isolates from the previously identified three Cd25-defined major clades and the four ITS genotypes. Dendrograms created by using the unweighted pair group method with arithmetic averages that were generated using the data from all 10 loci revealed a population structure which supports that previously suggested by DNA fingerprinting and ITS genotyping. The MLST data revealed significantly less divergence within the C. dubliniensis population examined than within the C. albicans population. These findings show that MLST can be used as an informative alternative strategy for investigating the population structure of C. dubliniensis. On the basis of the highest number of genotypes per variable base, we recommend the following eight loci for MLST analysis of C. dubliniensis: CdAAT1b, CdACC1, CdADP1, CdMPIb, CdRPN2, CdSYA1, exCdVPS13, and exCdZWF1b, where “Cd” indicates C. dubliniensis and “ex” indicates extended sequence. 相似文献
60.
Seminotti B da Rosa MS Fernandes CG Amaral AU Braga LM Leipnitz G de Souza DO Woontner M Koeller DM Goodman S Wajner M 《Molecular genetics and metabolism》2012,106(1):31-38
In the present work we evaluated a variety of indicators of oxidative stress in distinct brain regions (striatum, cerebral cortex and hippocampus), the liver, and heart of 30-day-old glutaryl-CoA dehydrogenase deficient (Gcdh(-/-)) mice. The parameters evaluated included thiobarbituric acid-reactive substances (TBA-RS), 2-7-dihydrodichlorofluorescein (DCFH) oxidation, sulfhydryl content, and reduced glutathione (GSH) concentrations. We also measured the activities of the antioxidant enzymes glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD) and glucose-6-phosphate dehydrogenase (G6PD). Under basal conditions glutaric (GA) and 3-OH-glutaric (3OHGA) acids were elevated in all tissues of the Gcdh(-/-) mice, but were essentially absent in WT animals. In contrast there were no differences between WT and Gcdh(-/-) mice in any of the indicators or oxidative stress under basal conditions. Following a single intra-peritoneal (IP) injection of lysine (Lys) there was a moderate increase of brain GA concentration in Gcdh(-/-) mice, but no change in WT. Lys injection had no effect on brain 3OHGA in either WT or Gcdh(-/-) mice. The levels of GA and 3OHGA were approximately 40% higher in striatum compared to cerebral cortex in Lys-treated mice. In the striatum, Lys administration provoked a marked increase of lipid peroxidation, DCFH oxidation, SOD and GR activities, as well as significant reductions of GSH levels and GPx activity, with no alteration of sulfhydryl content, CAT and G6PD activities. There was also evidence of increased lipid peroxidation and SOD activity in the cerebral cortex, along with a decrease of GSH levels, but to a lesser extent than in the striatum. In the hippocampus only mild increases of SOD activity and DCFH oxidation were observed. In contrast, Lys injection had no effect on any of the parameters of oxidative stress in the liver or heart of Gcdh(-/-) or WT animals. These results indicate that in Gcdh(-/-) mice cerebral tissue, particularly the striatum, is at greater risk for oxidative stress than peripheral tissues following Lys administration. 相似文献