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81.
Orlando Jorge M. Torres Fabricio Ferreira Coelho Antonio Nocchi Kalil Marcos Belotto Eduardo José B Ramos Angelica Maria Lucchese José Maria A Moraes-Junior Paulo Cezar G Amaral Gilton Marques Fonseca Paulo Herman 《Asian journal of surgery / Asian Surgical Association》2021,44(3):553-559
BackgroundIntrahepatic lithiasis (IHL) is a rare disease in the western world. Complications associated with IHL include acute cholangitis, liver atrophy, secondary biliary cirrhosis, and risk for intrahepatic cholangiocarcinoma. Liver resection is considered the treatment of choice for IHL. The objective of this study was to analyze patients who underwent liver resection for non-Asian hepatolithiasis.Methods127 patients with symptomatic non-Asian hepatolithiasis underwent resection in six institutions. Demographic data, clinical presentation, diagnosis, classification according to stone location, presence of atrophy, bile duct stricture, biliary cirrhosis, incidence of cholangiocarcinoma, treatment and postoperative course were evaluated.Results52 patients (40.9%) were male and the mean age was 46.1 years. Sixty-six patients (51.9%) presented with history of cholangitis. Stones were located in the left lobe in 63 (49.6%), and right lobe in 28 patients (22.0%). Atrophy was observed in 31 patients (24.4%) and biliary stenosis in 18 patients (14.1%). The most common procedure performed was left lateral sectionectomy in 63 (49.6%) patients, followed by left hepatectomy in 36 (28.3%), right hepatectomy in 19 (15.0%), and associated hepaticojejunostomy in 28 (22.0%). Forty-two patients (33.0%) presented postoperative complications and the most common were biliary fistula (13.3%) and surgical site infection (7.0%). Postoperative mortality was 0.7%. Intrahepatic cholangiocarcinoma was observed in 2 patients (1.5%). Recurrence was identified in 10 patients (7.8%), mostly with bilateral stones and/or hepaticojejunostomy.ConclusionLiver resection is the standard treatment for symptomatic unilateral or complicated IHL with good operative results. Risk of cholangiocarcinoma was low in non-Asian patients. 相似文献
82.
Sergio Agudiez-Calvo Jorge Ballesteros-Frutos Héctor Raúl Cabezas-García Daniel Pecos-Martin Tomás Gallego-Izquierdo 《The Journal of foot and ankle surgery》2021,60(2):247-251
The aim of this study was the validation and transcultural adaptation of the Pain Scale for Plantar Fasciitis to Spanish, following the steps defined by “Guidelines for the process of cross-cultural adaptation of self-report measures.” A cross-sectional study was driven in 153 patients with unilateral plantar fasciitis diagnosis. Statistical analysis measured the internal consistency, the test-retest reliability, the construct validity with the Spanish version of Foot and Function Index, and a factorial analysis. The questionnaire Pain Scale for Plantar Fasciitis was also given to a group of 10 people who received a physiotherapy treatment based on manual therapy, therapeutic exercise, and health education, which aim was to determine the questionnaire's sensitivity to changes. The questionnaire showed high internal consistency and test-retest reliability (Cronbach's α = 0.99, intraclass correlation coefficient = 0.98 [0.97-0.98]), good convergent validity with a moderate correlation with the Foot and Function Index (rho = 0.677, p < .0001) and no floor or ceiling effects were detected. The factorial analysis revealed that the first 3 factors showed 42.47% of variance, finding only 1 latent feature. Statistically significant differences were found in those patients who received physiotherapy treatment after 1 month, revealing that the questionnaire was sensitive to changes in the symptoms of subjects with plantar fasciitis. The Spanish version of Pain Scale for Plantar Fasciitis has proved to be a valid, reliable, and change-sensitive tool for patients with plantar fasciitis. 相似文献
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85.
The objective of this work is to investigate the feasibility of conceptual similarity metrics in the framework of the Unified Medical Language System (UMLS). We have investigated an approach based on the minimum number of parent links between concepts, and evaluated its performance relative to human expert estimates on three sets of concepts for three terminologies within the UMLS (i.e., MeSH, ICD9CM, and SNOMED). The resulting quantitative metric enables computer-based applications that use decision thresholds and approximate matching criteria. The proposed conceptual matching supports problem solving and inferencing (using high-level, generic concepts) based on readily available data (typically represented as low-level, specific concepts). Through the identification of semantically similar concepts, conceptual matching also enables reasoning in the absence of exact, or even approximate, lexical matching. Finally, conceptual matching is relevant for terminology development and maintenance, machine learning research, decision support system development, and data mining research in biomedical informatics and other fields. 相似文献
86.
Isolation of putative dengue virus receptor molecules by affinity chromatography using a recombinant E protein ligand 总被引:3,自引:0,他引:3
Nucleotide sequences coding for the full-length envelope (E) glycoprotein gene of dengue virus type 4 was amplified using an RT-PCR method from infected C6/36 cells and cloned into pPROEx-Hta expression vector. The expression of the recombinant E protein in Escherichia coli was confirmed by Western blot using a polyclonal anti-dengue polyclonal antibody. The His-tagged fusion protein was obtained from the bacterial cellular extracts in almost pure form by immobilized metal affinity chromatography and the recombinant protein retained its ability to bind to 40 and 45 kDa proteins, previously described as putative receptors for dengue virus in C6/36 cells. To purify the 40 and 45 kDa molecules, a total protein extract from C6/36 cells was passed through an affinity chromatography column using immobilized recombinant E protein. After washing with isotonic buffer, elution was accomplished using a high salt buffer. The two proteins obtained, with molecular weights of 40 and 45 kDa, were recognized by dengue 4 virus, in virus overlay protein binding assay. This procedure allows further characterization of molecules that could be involved in dengue binding and entry. 相似文献
87.
Sonia Raskovsky Emilio Rivas Delia Bernik Jorge Medina Diana Jerusalinsky 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1990,13(1-2):17-32
The modulation of the binding of muscarinic cholinergic receptor ligands by phosphatidylserine purified from bovine cerebral cortex (BC-PS) was examined in vitro and in vivo. The enrichment of bovine cerebral cortical synaptosomal membranes with BC-PS, using a fusion technique, produced a concentration-dependent decrease in the affinity (increase in K d ) of [3H]quinuclidinyl benzylate (3H-QNB) specific binding to muscarinic acetylcholine receptors (mAChR), without changes in their maximal number (Bmax). Similar results were observed when [3H]oxotremorine (3H-OXO) was used to label a high affinity subpopulation of mAChR. On the other hand, preincubation of BC-PS liposomes with synaptosomal membranes in a nonoptimum fusion condition (at pH 7.4) did not alter the binding properties of both radioligands. Fusion experiments using a pure phosphatidylserine preparation from spinal cord revealed a similar decrement in the affinity of3H-QNB specific binding. Five day’s intraperitoneal (i.p.) administration of 15 mg/kg of BC-PS liposomes in rats increased the maximal number of cerebral cortical binding sites for3H-OXO. Scatchard analysis revealed no changes in the apparent dissociation constant. This modification is selective in relation to the neural structure studied. Thus, BC-PS treatment did not modify3H-OXO binding in the hippocampal formation and cerebellum. In contrast, parallel experiments using the muscarinic antagonist3H-QNB showed no alteration in the binding properties of mAChR. Five day’s i.p. administration of 15 mg/kg/d of phosphatidylcholine from bovine cerebral cortex (BC-PC) liposomes produced quite similar results to those obtained with BC-PS. These results indicate that mAChR are under the modulatory action of phosphatidylserine (PS) and phosphatidylcholine (PC), and suggest that this endogenous phospholipids may play a regulatory role on the mAChR. The possible implications of these findings on the effects of PC or PS treatment in neurological disorders involving a decrease in central cholinergic functions are discussed. 相似文献
88.
Jorge G. Arroyo Siavash Ghazvini Devron H. Char 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(7):411-414
Background: We report a modified method for the isolation and propagation of adult human Müller cells in culture. Methods: The retina of postmortem human eyes was mechanically dissociated and cultured. Using immunocytochemical techniques, these cells were stained with monoclonal antibodies specific for Müller cells, glial fibrillary acidic protein (GFAP), vimentin, glutamine synthetase (GS) and keratin. Transmission electron microscopy (TEM) was also performed. Results: The dissociated and cultured cells expressed vimentin and GS, but not GFAP. At least 85% of these cells stained with a Müller tell-specific monoclonal antibody. Using TEM, flat cells containing 13-nm intermediate filaments and glycogen were identified. Conclusion: Human retinal Müller cells tan be isolated and propagated in culture. Purified cell cultures are required for controlled studies of the normal physiology and pathologie responses of Müller cells. 相似文献
89.
Ritsuko Akiyama Kunyan Kuang Pablo A. Chiaradía Calvin W. Roberts Jorge Fischbarg 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(6):384-387
Background: Anterior chamber miotic solutions are widely used in ophthalmic surgery to induce pupillary contraction. We investigated whether the acetylcholine, carbachol, or mannitol present in perfusing solutions can affect corneal endothelial function. Methods: Freshly dissected deepithelized rabbit corneas were mounted in a Dikstein-Maurice chamber at 36 °C. The endothelial sides were perfused with six solutions: (A) 55 mM (1%) acetylcholine Cl plus modified balanced salts; (B) control for A, with acetylcholine Cl replaced by sucrose; (C) 0.55 mM (0.01%) carbachol Cl plus balanced salts; (D) balanced salts solution (BS; control for C); (E) 3% mannitol plus modified balanced salts; and (F) modified balanced salts (control for E, with mannitol replaced by sucrose). Corneal thickness was followed for 3 h in each experiment. The effect of solution E did not differ from that of solution F. Results: The carbachol-containing solution produced a small increase in corneal thickness compared to the control solution, while the acetylcholine-containing solution resulted in corneal thickness lower than that in control preparations. Conclusion: From these data, acetylcholine is harmless to the endothelium, and may actually stimulate its fluid pump mechanism. Carbachol, on the other hand, appears to have a detrimental effect. 相似文献
90.
Health care delivery in Mexico is divided in three groups: a social sector that covers approximately 53% of the population and is financed by the labor force, the state and the employer; a public, or open, sector that covers 33% of the population and is financed by federal and state funds; and a private sector that covers about 5% of the population and has two categories, the not-for-profit hospitals and the profit-oriented institutions. Most medical practitioners can work in any of the three groups or in several. Nine percent of Mexico's population, because of extreme ignorance, poverty, or isolation, have no or limited access to medical care. Mexico has 58 medical schools, which graduate about 7800 new physicians annually, awarding them the title Medico cirujano (Physician Surgeon). There are more than 160,000 physicians in Mexico, 20,000 of whom are unemployed. Each year, approximately 12,000 physicians compete for the 4306 places in the official residency training programs for all specialties. Of those taking the examination, 2000 try to get one of the 625 slots available for training in general surgery. Most of the surgical training programs in Mexico have a 3-year duration. The Mexican Academy of Surgery, the Mexican Society of General Surgery, and the Mexican Board of Surgery, as well as private individuals and organizations, are working to improve the quality of medical education and trying to establish a 5-year training program in surgery. The rapid movement toward modernization that is sweeping the country must include the improvement of surgical education as well.
Resumen La atención de la salud en México está dividida en tres grupos: el Sector Social que cubre approximadamente el 53% de la población y que está financiado por la fuerza laboral, el Estado y el empleador; un Sector Público o Abierto que cubre el 33% de la población y que es financiado con fondos federales y estatales; y un Sector Privado que cubre el 5% de la población y que posee dos categorías: la de los hospitales sin ánimo de lucro y la de las instituciones con ánimo de lucro. La mayoría de los médicos pueden trabajar en cualquiera de los 3 grupos, o en combinación. El 9% de la población mexicana, por extrema ignorancia, pobreza y aislamiento no posee acceso alguno, o sólo lo tiene mínimo, a la atención médica.México posee 58 facultades de medicina, las cuales gradúan alrededor de 7.800 nuevos médicos anualmente, a quienes se les expide el título de médico cirujano.Hay más de 160.000 médicos en México, 20.000 de los cuales se encuentran desempleados. Cada año aproximadamente 12.000 médicos compiten por las 4.306 plazas en los programas oficiales de adiestramiento en las diferentes especialidades. De aquellos que presentan examen, 2.000 tratan de obtener uno de los 625 lugares disponibles para adiestramiento en círugía general.La mayoría de los programas de adiestramiento quirúrgico en la nación son de tres años de duración. La Academia Mexicana de Cirugía, la Asociación Mexicana de Cirugía General y el Consejo Mexicano de Cirugía, así como individuos y organizaciones privadas, trabajan en pro del mejoramiento de la calidad de la educación médica y tratan de establecer un programa de adiestramiento en cirugía de cinco años de duración. Los rápidos cambios de modernización que ocurren en el país deben incluir también el mejoramiento de la educación quirúrgica.
Résumé L'administration des soins au Mexique est repartie entre trois secteurs: 1) Le secteur social qui couvre environ 53% de la population et qui est financé par la caisse des ouvriers, celle de l'état et celle du patronat; 2) un secteur public ou ouvert, qui couvre environ 33% de la population et qui est financé par des fonds fédéraux et gouvernementaux et enfin 3) un secteur privé, qui ne couvre que 5% environ de la population et qui comprend deux catégories, les hôpitaux à but non-lucratif et les institutions à but lucratif. La plupart des médecins peuvent exercer dans un ou plusieurs de ces trois groupes. Neuf pourcent de la population, en raison d'une extrême pauvreté, de son ignorance ou de son éloignement, a peu ou pas d'accés à des soins structurés.Il y a 58 écoles de Médecine au Mexique, produisant environ 7800 nouveaux médecins par an. Ils reçoivent le titre de Medico Cirujano littéralement, Médecin chirurgical. Il existe plus de 160000 médecins au Mexique, dont 20000 sont sans travail. Chaque année, environ 12000 médecins sont en compétition pour obtenir un des 4306 postes officiels de résidents, toutes spialités confondues. Parmi ceux qui se présentent, 2000 sont candidats pour un poste en chirurgie. La plupart des programmes d'enseignement durent trois ans. L'Académie de Chirurgie Mexicaine, La Société Mexicaine de chirurgie Générale et le comité d'accréditation chirurgicale, tout en accord avec les institutions privées et leur dirigeants oeuvrent pour un programme de cinq ans. La vague de progrès, ressentie dans tous les domaines, qui traverse actuellement le pays doit aussi intéresser l'amélioration de l'enseignement en chirurgie.相似文献