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81.
目的:为探讨矫正型大动脉转位的病理解剖特点及手术技术。方法:本组6例均为SLL型,手术包括:室间隔缺损修补4例、肺动脉瓣切开1例、静脉室肺动脉外通道1例、房室瓣替换1例。结果:全组手术死亡1例。主要手术并发症为低心排4例、完全性房室传导阻滞1例及残余左房室瓣关闭不全1例。结论:矫正型大动脉转位的病理解剖有一定的特殊性,应按不同的合并畸型选择不同术式,正确处理室间隔缺损、肺动脉流出道狭窄及左房室瓣关闭不全是外科手术的关键。 相似文献
82.
Nuclear apoptosis induced by isolated mitochondria 总被引:2,自引:0,他引:2
We isolated and purified mitochondria from mouse livers and spinach leaves.When added into egg extracts of Xenopus laevis,they caused nuclei of mouse liver to undergo apoptotic changes.Chromatin condensation,margination and DNA ladder were observed.After incubating isolated mitochondria in some hypotonic solutions,and centrifuging these mixtures at mgh speed,we got mitochondrial supernatants.It was found that in the absence of cytosolic factor,the supernatant alone was able to induce apoptotic changes in nuclei.The effective components were partly of protein.DNA fragmentation was partly inhibited by caspase inhibitors AC-DEVD-CHO and AC-YVAD-CHO.Meanwhile,caspase inhibitors fully blocked chromatin condensation.Primary characterization of the nuclear endonuclease(s) induced by mitochondrial supernatants was also conducted.It was found that this endonuclease is different from endonuclease G,cytochrome c-induced nuclease,or Ca^2 -activated endonuclease. 相似文献
83.
84.
The expression in females of ornaments thought to be the target of sexual selection in males is a long-standing puzzle. Two main hypotheses are proposed to account for the existence of conspicuous ornaments in both sexes (mutual ornamentation): genetic correlation between the sexes and sexual selection on females as well as males. We examined the pattern of ornament gains and losses in 240 species of dragon lizards (Agamidae) in order to elucidate the relative contribution of these two factors in the evolution of mutual ornamentation. In addition, we tested whether the type of shelter used by lizards to avoid predators predicts the evolutionary loss or constraint of ornament expression. We found evidence that the origin of female ornaments is broadly consistent with the predictions of the genetic correlation hypothesis. Ornaments appear congruently in both sexes with some lineages subsequently evolving male biased sexual dimorphism, apparently through the process of natural selection for reduced ornamentation in females. Nevertheless, ornaments have also frequently evolved in both sexes independently. This suggests that genetic correlations are potentially weak for several lineages and sexual selection on females is responsible for at least some evolutionary change in this group. Unexpectedly, we found that the evolutionary loss of some ornaments is concentrated more in males than females and this trend cannot be fully explained by our measures of natural selection. 相似文献
85.
86.
Bernd Fritzsch 《Cell and tissue research》1980,213(2):325-341
Summary The retinal projections to the brain were studied in three species of European Salamandridae using anterograde transport of horseradish peroxidase and autoradiography. The results obtained were basically identical for all species and confirmed earlier findings on the fiber supply to the preoptic nucleus and the basal optic neuropil. In the anterior thalamus projections to three distinct terminal fields are clearly visible: (i) the diffusely stained corpus geniculatum thalamicum, (ii) the neuropil of Bellonci, pars lateralis, and (iii) a dorsomedial terminal field, the neuropil of Bellonci, pars medialis. Caudal to these terminal fields is an almost terminal-free region, the lateral neuropil. In the posterior thalamus a medial terminal field, the uncinate field, and a laterally located terminal field, the posterior thalamic neuropil, are distinguishable. The tectum opticum displays as many as four dense layers of retinofugal fibers and terminals in the rostral part and, in addition, a more densely stained strip of neuropil running from rostral to caudal over the tectum. The extent of ipsilateral fibers is greater than previously reported in other urodele species. They supply the medial and the lateral parts of the neuropil of Bellonci, the uncinate field, and reach the tectum opticum via the medial optic tract. Further, they form terminals in the innermost optic fiber layer throughout the rostral half of the ipsilateral tectum. A small proportion of ipsilateral fibers contributes very sparsely to all other thalamic terminal fields, leaving only the caudal part of the tectum and several layers of the rostral tectum completely free of a direct retinofugal fiber supply. 相似文献
87.
This study was designed to localize transforming growth factor alpha (TGF-) and epidermal growth factor receptor (EGFR) expression in the developing human gastrointestinal tract and pancreas. Immunohistochemical techniques using specific antibodies against human TGF- and EGFR were performed on digestive tissues of fetuses from 9 to 10 to 24 weeks of gestation, children and adults. In fetuses, TGF- and EGFR proteins were expressed in all epithelial tissues studied with a good correlation and from an age as early as 9 to 10 weeks of gestation, except for TGF- in the esophagus. The strongest TGF- immunostaining was noted in the stomach and the proximal colon. Unexpectedly, immunoreactive gut endocrine cells were observed with the two antibodies used. Relatively numerous in fetuses, they decreased in number with age and were rare in adults particularly along the colon. Enteroglucagon-secreting cells were shown to express TGF- while some gastrin, somatostatin and pancreatic glucagon cells were immunostained with EGFR antibodies. The presence of TGF- and of its recetor in digestive tract epithelium and pancreatic tissues early in fetal life suggests a functional role for TGF- during the developmental process of the digestive system. We demonstrate that TGF- is also produced by endocrine cells and might have an additional mode of action other than paracrine, at least during fetal life. 相似文献
88.
Ashley MV Caballero IC Chaovalitwongse W Dasgupta B Govindan P Sheikh SI Berger-Wolf TY 《Molecular ecology resources》2009,9(4):1127-1131
A software suite KINALYZER reconstructs full-sibling groups without parental information using data from codominant marker loci such as microsatellites. KINALYZER utilizes a new algorithm for sibling reconstruction in diploid organisms based on combinatorial optimization. KINALYZER makes use of a Minimum 2-Allele Set Cover approach based on Mendelian inheritance rules and finds the smallest number of sibling groups that contain all the individuals in the sample. Also available is a 'Greedy Consensus' approach that reconstructs sibgroups using subsets of loci and finds the consensus of the partial solutions. Unlike likelihood methods for sibling reconstruction, KINALYZER does not require information about population allele frequencies and it makes no assumptions regarding the mating system of the species. KINALYZER is freely available as a web-based service. 相似文献
89.
90.
目的探讨早产儿肠道微生态变化及其与胎龄、出生体质量的关系。方法选取2018年5月至2020年5月我院收治的80例早产儿作为早产组,同期收治的80例足月新生儿作为对照组。收集入组新生儿出生后3 d、3周的粪便,比较2组研究对象粪便标本中细菌丰富度和Shannon Wiener指数;根据早产组胎龄和出生体质量不同分组,分析胎龄、出生体质量与肠道微生态变化的关系。结果(1)出生3 d,早产组新生儿粪便标本的DGGE图谱条带数、Shannon Wiener指数均显著低于对照组(t=3.179、3.521,均P<0.05);(2)出生3 d,胎龄34+1~36+6周组新生儿粪便标本的DGGE图谱条带数、Shannon Wiener指数显著高于28~30周组、30+1~32周组和32+1~34周组(q=9.653、6.476、4.848和8.796、8.008、6.277,均P<0.05);(3)出生3 d,体质量>2 000 g组新生儿粪便标本的的DGGE图谱条带数、Shannon Wiener指数显著高于≤1 500 g组(q=5.601和4.593,均P<0.05);(4)不同出生体质量、胎龄的早产儿,出生3周粪便标本的DGGE图谱条带数、Shannon Wiener指数相比差异无统计学意义(F=1.577和2.326,均P>0.05)。结论与足月新生儿相比,早产儿出生后细菌定植出现延迟且多样性差,胎龄越小、出生体质量越低的早产儿的肠道菌群的多样性更低、定植延迟的可能性更大,出生3周后其肠道微生态逐渐恢复正常。 相似文献