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排序方式: 共有2421条查询结果,搜索用时 15 毫秒
1.
Ángel Becerra Héctor Trujillo Lucía Valencia Aurelio Rodríguez‐Pérez 《Brazilian Journal of Anesthesiology》2019,69(2):200-203
Background and objectives
A prompt and effective management of trauma patient is necessary. The aim of this case report is to highlight the importance of intraoperative echocardiography as a useful tool in patients suffering from refractory hemodynamic instability no otherwise explained.Case report
A 41 year‐old woman suffered a car accident. At the emergency department, no abnormalities were found in ECG or chest X‐ray. Abdominal ultrasound revealed the presence of abdominal free liquid and the patient was submitted to urgent exploratory laparotomy. Nevertheless, she persisted suffering arterial hypotension and metabolic acidosis. Looking for the reason of her hemodynamic instability, intraoperative transthoracic echocardiography was performed, finding out the presence of pericardial effusion. Once the cardiac surgeon extracted pericardial clots, patient's situation improved clinically and analytically.Conclusion
Every anesthesiologist should be able to use the intraoperative echocardiography as an effective tool in order to establish the appropriate measures to promote the survival of patients suffering severe trauma. 相似文献2.
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5.
P Pratesi E Grana M G Santagostino Barbone M I La Rotonda C Silipo A Vittoria 《Il Farmaco; edizione scientifica》1986,41(5):336-345
Proceeding in our study on the muscarinic receptor site, a refinement of its topology by means of Quantitative Structure-Activity Relationships has been carried out. Specific key structures have been selected considering not only muscarine and the corresponding desether derivative, but also a set of cyclopentenyltrimethylammoniummethyl salts. These derivatives, considered in a correlation equation extended to all of the five-membered cyclic structures previously examined, significantly improve understanding of contributions of critical ligand substructures to the overall interaction. The results obtained reinforce the reliability of correlation equations in structure-activity studies. 相似文献
6.
Emilia Lachica Aurelio Luna Enrique Villanueva 《International journal of legal medicine》1989,103(2):111-119
Summary The diagnosis of myocardial infarction requires the use of a group of tests that are very efficient, quick and inexpensive. Another important consideration is the choice of myocardial sampling zones, especially in cases of differential diagnosis between a cardiac injury secondary to a trauma or violent asphyxia and others, secondary to myocardial infarction. The aim of this work was to choose, through discriminant analysis, the most useful zones of cardiac tissue for the quantification of free fatty acids and free carnitine and for the performance of the K/Na quotient, as biochemical parameters for the postmortem diagnosis of myocardial infarction. According to the discriminant analysis performed, seven zones of cardiac tissue are necessary to achieve a differential diagnosis among myocardial infarction, other natural deaths, and violent deaths with a 71.9% efficacy. Greater diagnostic efficacy was found (78.1%) for differentiating between natural deaths and violent deaths.
Offprint requests to: E. Lachica 相似文献
7.
Giuseppina Mariucci Michela Tantucci Antonio Giuditta Maria Vittoria Ambrosini 《Neuroscience letters》2007
Transient focal ischemia induced in rat brain by occlusion of the middle cerebral artery (MCAo) elicits a generalized induction of the 72 kDa heat-shock protein (hsp72) heralding functional recovery. As this effect implies activation of protein synthesis, and local systems of protein synthesis are present in brain synapses, and may be analyzed in preparations of brain synaptosomes, we evaluated hsp72 expression and protein synthesis in synaptosomal fractions of spontaneously hypertensive rats (SHRs) subjected to permanent MCAo. SHRs were randomly divided in ischemics and sham controls, anaesthesia controls and passive controls. Focal ischemia was induced under chloral hydrate anaesthesia by unilateral permanent MCAo. Protein synthesis was determined by [35S]methionine incorporation into synaptosomal proteins from ischemic and contralateral cortex/striatum, and from cerebellum. Hsp72 expression was measured in the same fractions by immunoblotting. Our data demonstrate that under these conditions synaptic hsp72 markedly increases in the ischemic hemisphere 1 and 2 days after MCAo, progressively declining in the following 2 days, while no significant change occurs in control rats. In addition, in the ischemic hemisphere the rate of synaptic protein synthesis increases more than two-fold between 1 and 4 days after MCAo, without showing signs of an impending decline. The present data provide the first demonstration that synaptic protein synthesis is massively involved in brain plastic events elicited by permanent focal ischemia. 相似文献
8.
Licata A Ainis L Martella S Ricca MB Licata P Lauriano ER Zaccone G 《Acta histochemica》2002,104(3):289-295
The epidermis of the earthworm Lumbricus terrestris is a multifunctional tissue. It is composed of supporting, mucous, neuroendocrine-like, sensory and basal cells. NO is considered to be a molecule that regulates numerous functional activities (also in non-neuronal cells) in vertebrates. In the earthworm epidermis, we found neuronal NO synthase immunopositivity in orthochromatic and metachromatic mucous cells, neuroendocrine-like cells and in epidermal and subepidermal nerve fibers and striated muscle fibers. It is suggested that NO has a multitude of biological actions, affecting functional activities of the epidermis such as tissue homeostasis, control of secretion, proliferation, respiration, defense, water-salt balance, as well as regulation of tonus in vascular and striated muscles. 相似文献
9.
Fadda G Muie A Rufini V Ardito G Revelli L Fiorino MC Capelli A 《Endocrine pathology》2000,11(4):373-377
Cystic lesions of the thyroid are common findings. Although many thyroid cysts are of benign, some cases of hemorrhagic degenerative
changes occur in neoplastic nodules, mostly follicular neoplasms and papillary carcinomas. The occurrence of hemorrhagic changes
in medullary carcinomas has never been documented with aspirative cytological and histological pictures to the best of our
knowledge. A case of medullary thyroid carcinoma with a large central hemorrhagic cyst is described, and the literature regarding
the pathogenesis of this regression and the occurrence of cystic neoplasms in the thyroid is reviewed. 相似文献
10.
CD44 Isoform Expression Follows Two Alternative Splicing Pathways in Breast Tissue 总被引:1,自引:0,他引:1
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Xavier Roca Jos L. Mate Aurelio Ariza Ana M. Muoz-Mrmol Claudia von Uexküll-Güldeband Inmaculada Pellicer Jos J. Navas-Palacios Marcos Isamat 《The American journal of pathology》1998,153(1):183-190
The repertoire of distinct CD44 protein isoforms is generated by means of alternative pre-mRNA splicing of 10 variable exons located in the central region of the CD44 gene. We have used human breast ductal carcinoma as a model to identify two alternative splicing pathways of the CD44 pre-mRNA variable region that account for the generation of all of the CD44 isoforms described in breast tissue. An alternative splicing pathway that reflects inclusion of variable exons in a gradual 3′-to-5′ fashion is evidenced in breast ductal carcinoma and its lymph node metastases. This pathway is compatible with a mechanism that generates the standard form of CD44 (devoid of variable exons) and is distinguishable from an alternative splicing pathway that involves exclusively variant exon 3 and is observable in both normal and carcinoma breast tissue. We show that both pathways are detectable in the same cell type in the breast and provide a speculative model by which these splicing routes could take place. 相似文献