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31.
Wireless Ultrasound Guidance for Femoral Venous Cannulation in Electrophysiology: Impact on Safety,Efficacy, and Procedural Delay 下载免费PDF全文
DANIEL RODRÍGUEZ MUÑOZ M.D. EDUARDO FRANCO DÍEZ M.D. JAVIER MORENO M.D. Ph.D. GIUSEPPE LUMIA M.D. ALEJANDRA CARBONELL SAN ROMÁN M.D. TERESA SEGURA DE LA CAL M.D. ROBERTO MATÍA FRANCÉS M.D. Ph.D. ANTONIO HERNÁNDEZ MADRID M.D. Ph.D. JOSÉ LUIS ZAMORANO GÓMEZ M.D. Ph.D. 《Pacing and clinical electrophysiology : PACE》2015,38(9):1058-1065
32.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
33.
目的:对蒙药嘎日迪-5味丸的方源考证及其现代研究进展进行综述,为该复方的进一步开发与利用提供依据。方法:采用蒙医文献研究与考证、文献综述方法,从基源、方解、临床应用以及化学成分等方面对蒙药嘎日迪-5味丸研究现状进行总结和分析。结果:蒙药嘎日迪-5最早收载于藏医学家宇妥·云丹贡布于公元8世纪下旬撰写的藏医经典著作《四部医典》,属于蒙药、藏药传统验方,由诃子、麝香、草乌(制)、石菖蒲、木香配伍组成,其他处方都是在使用的过程中,根据临床应用演变而来,具有杀黏、止痛、消肿、燥协日乌素功效。蒙医临床用于治疗黏引起的瘟疫热症、黏虫病、黏性刺痛、维生素C缺乏病、风湿、白喉炭疽、瘰疬疮疡、正偏头痛、疥癣等疾病,疗效显著。结论:蒙药嘎日迪-5方出自《四部医典》,属传统验方,对瘟疫热症、黏虫病、黏性刺痛等黏性疾病疗效显著,具有潜在的开发利用价值。 相似文献
34.
Delivery of a hammerhead ribozyme specifically down-regulates the production of fibrillin-1 by cultured dermal fibroblasts 总被引:4,自引:1,他引:4
Kilpatrick MW; Phylactou LA; Godfrey M; Wu CH; Wu GY; Tsipouras P 《Human molecular genetics》1996,5(12):1939-1944
The hammerhead ribozyme is a small catalytic RNA molecule. Potential
hammerhead ribozymes that possess a catalytic domain and flanking sequence
complementary to a target mRNA can cleave in trans at a putative cleavage
site within the target molecule. We have investigated the potential of
hammerhead ribozymes to down-regulate the product of the fibrillin-1 gene
(FBN1). Fibrillin is a 347 kDa glycoprotein that is a major constituent of
the elastin-associated microfibrils. Mutations in the FBN1 gene are
responsible for Marfan syndrome (MFS), a common systemic disorder of the
connective tissue. Many FBN1 mutations responsible for MFS appear to act in
a dominant-negative fashion, raising the possibility that reduction of the
amount of product from the mutant FBN1 allele might be a valid therapeutic
approach for MFS. A trans-acting hammerhead ribozyme (FBN1-RZ1) targeted to
the 5' end of the human FBN1 mRNA has been designed and synthesized, and
shown to cleave its target efficiently in vitro. FBN1-RZ1 cleavage is
magnesium dependent and efficient at both 37 and 50 degrees C. Delivery of
the FBN1-RZ1 ribozyme into cultured dermal fibroblasts, by receptor-
mediated endocytosis of a ribozyme-transferrin-polylysine complex,
specifically reduces both cellular FBN1 mRNA and the deposition of
fibrillin in the extracellular matrix. These results suggest that the use
of hammerhead ribozymes is a valid approach to the study of fibrillin gene
expression and possibly to the development of a therapeutic approach to
MFS.
相似文献
35.
Ca2+ and phospholipid-dependent protein kinase (protein kinase C) activity is not necessarily required for secretion by human neutrophils 总被引:2,自引:0,他引:2
Ca2+-dependent and phospholipid-dependent protein kinase (PKC) is a receptor for and is activated by phorbol esters. This enzyme is reportedly involved in the mechanism of superoxide anion (O2-) production and the release of intracellular granule contents from human neutrophils. As previously reported by others, we found that greater than 75% of the total cellular PKC activity existed in a soluble form in untreated neutrophils and that this activity was enhanced in a dose- dependent manner by phorbol 12-myristate 13-acetate (PMA) and by phorbol 12,13-dibutyrate (PDBu). Furthermore, mezerein, an analogue of PMA that is thought to be a competitive inhibitor, did not activate PKC, and on the contrary, inhibited PMA-stimulated activity in a dose- dependent manner. Pretreatment of intact neutrophils with PMA or PDBu caused the "translocation" of PKC activity to the insoluble cell fraction; PKC translocation was not detected after mezerein stimulation at any of the tested concentrations. Neither did mezerein cause an increase in intracellular Ca2+, as monitored by Quin 2 fluorescence. Both phorbol esters and mezerein stimulated intact neutrophils to generate O2- and release lysosomal enzymes into the extracellular medium. Finally sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated key differences in the patterns of endogenous phosphoproteins of neutrophils stimulated with phorbol as compared with mezerein. We therefore suggest that PKC activation may not be the only pathway required to elicit neutrophil responses. 相似文献
36.
Coexistence of benign phyllodes tumor and invasive ductal carcinoma in distinct breasts: case report
Guerino Barbalaco Neto Claudia Rossetti Natalia A Souza Fernando LA Fonseca Ligia Ajaime Azzalis Virginia Berlanga Campos Junqueira Vitor E Valenti Luiz Carlos de Abreu 《European journal of medical research》2012,17(1):8
This report describes a rare case of coexistence of benign phyllodes tumor, which measured 9 cm in the right breast, and invasive ductal carcinoma of 6 cm in the left breast, synchronous and independent, in a 66-year-old patient. The patient underwent a bilateral mastectomy due to the size of both lesions. Such situations are rare and usually refer to the occurrence of ductal or lobular carcinoma in situ when associated with malignant phyllodes tumors, and more often in ipsilateral breast or intra-lesional. 相似文献
37.
Artifon EL Takada J Okawa L Ferreira F Santos M Moura EG Otoch JP Sakai P 《Revista de gastroenterologia de Mexico》2011,76(3):270-274
Biliary endoscopic drainage using metallic self-expanded stents has become a well-established method for palliative treatment of malignant biliary obstruction. However, its occlusion, mainly by tumor overgrowth, is still the main complication without a standard treatment. We here describe a new method of treatment for biliary metallic stent occlusion, through the echo guided biliary drainage. We present a 68-year-old patient with metastatic pancreatic cancer previously treated for jaundice with ERCP and self-expandable metallic stent insertion. Four weeks later, the patient developed jaundice and symptoms of gastric outlet obstruction. A new ERCP confirmed obstruction of the second portion of the duodenum, due to diffuse tumor growth. EUS was performed, and the previous metal biliary stent was seen occluded at the distal portion in the common bile duct. A EUS-guided choledocododenostomy was performed and then, an overlapping self-expanding metal enteral stent was placed through the malignant obstruction. There were no early complications and the procedure was also clinically effective in relieving jaundice and gastric outlet obstruction symptoms. If ERCP fails in the management of occluded biliary metallic stents, EUS biliary drain can provide effective biliary decompression and should be considered an alternative to other endoscopic techniques. 相似文献
38.
Global vascular expression of murine CD34, a sialomucin-like endothelial ligand for L-selectin 总被引:19,自引:2,他引:19
Extravasation of leukocytes into organized lymphoid tissues and into sites of inflammation is critical to immune surveillance. Leukocyte migration to peripheral lymph nodes (PLN), mesenteric lymph nodes (MLN) and Peyer's patches (PP) depends on L-selectin, which recognizes carbohydrate-bearing, sialomucin-like endothelial cell surface glycoproteins. Two of these ligands have been identified at the molecular level. One is the potentially soluble mucin, GlyCAM 1, which is almost exclusively produced by high endothelial venules (HEV) of PLN and MLN. The second HEV ligand for L-selectin is the membrane-bound sialomucin CD34. Historically, this molecule has been successfully used to purify human pluripotent bone marrow stem cells, and limited data suggest that human CD34 is present on the vascular endothelium of several organs. Here we describe a comprehensive analysis of the vascular expression of CD34 in murine tissues using a highly specific antimurine CD34 polyclonal antibody. CD34 was detected on vessels in all organs examined and was expressed during pancreatic and skin inflammatory episodes. A subset of HEV-like vessels in the inflamed pancreas of nonobese diabetic (NOD) mice are positive for both CD34 and GlyCAM 1, and bind to an L-selectin/immunoglobulin G (IgG) chimeric probe. Finally, we found that CD34 is present on vessels of deafferentiated PLN, despite the fact that these vessels are no longer able to interact with L-selectin or support lymphocyte binding in vitro or trafficking in vivo. Our data suggest that the regulation of posttranslational carbohydrate modifications of CD34 is critical in determining its capability to act as an L-selectin ligand. Based on its ubiquitous expression, we propose that an appropriately glycosylated form of vascular CD34 may act as a ligand for L-selectin-mediated leukocyte trafficking to both lymphoid and nonlymphoid sites. 相似文献
39.
Limited red blood cell (RBC) regeneration often prevents collection of sufficient blood from autologous donors. We studied the effects of subcutaneous recombinant erythropoietin (rEPO) in subjects making frequent blood donations. Six healthy iron-replete male subjects took rEPO (200 U/kg) subcutaneously daily, and donated blood (450 mL) twice a week for 3 weeks. During a control study, these subjects also attempted twice-weekly blood donations without rEPO. Four other males given rEPO, including one with idiopathic hemochromatosis, waited until day 8 to begin blood donations. All healthy subjects took oral ferrous sulfate. Subcutaneous rEPO given with blood donations resulted in a marked reticulocytosis (mean peak value 568 +/- 159 x 10(9)/L v 235 +/- 77 x 10(9)/L, control study; P < .05), and enhanced RBC production at 28 days (1,208 +/- 227 mL v 719 +/- 161 mL, P < .05). rEPO in advance of blood donations was slightly less effective in normal subjects (941 +/- 139 mL, P < .05); however, the subject with hemochromatosis produced substantially more RBCs (1,764 mL) than any normal subject. rEPO-treated normal subjects (but not the rEPO-treated patient with hemochromatosis or untreated controls) produced iron-deficient RBCs with elevated zinc protoporphyrin levels and low hemoglobin content. These cells appeared within 1 week of rEPO administration and before laboratory confirmation of depleted iron stores. Thus, subcutaneous rEPO is an effective stimulant of erythropoiesis in nonanemic blood donors. However, in addition to eventual depletion of iron stores, early functional iron deficiency affects response to the drug. 相似文献
40.
We have recently found that antibodies to L-selectin, the homing receptor on neutrophils, are as effective as those to beta 2-integrin at blocking formyl peptide-stimulated aggregation. Therefore, we investigated the requirements for expression of L-selectin and beta 2- integrin on adjacent cells during aggregation. Fluorescence flow cytometry allowed characterization of aggregates on the basis of size and color, as well as antibody binding to these two adhesive molecules. Formyl peptide-stimulated aggregate formation was measured for individual populations fluorescently labeled red (LDS-751) or green (CD44-FITC), and interpopulation red-green cell conjugates. Blocking either the beta 2-integrin or L-selectin adhesive epitope with monoclonal antibody on individual cell populations resulted in an approximately 50% reduction in two-color aggregation as compared with that in unblocked samples. Shedding the L-selectin on a cell population by preincubation with complexes of lipopolysaccharide and its plasma membrane binding protein also decreased aggregation to a control population by approximately 50%. We examined the aggregation of neutrophils from patients genetically deficient in beta 2-integrin and clinically leukocyte adhesion deficient (LAD). LAD adhesion to normal neutrophils was dependent on the expression of L-selectin on LAD cells and beta 2-integrin on normal cells. Thus, the minimum requirement for adhesion between two mixed populations of neutrophils was that one population expressed the beta 2-integrin and the other expressed the L- selectin adhesive epitope. 相似文献