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21.
Use of the Honan balloon as a compression device for intravitreal triamcinolone acetonide injection.
Obtaining a lower intraocular pressure (IOP) before an intravitreal injection is important to avoid the danger of an immediate increase in IOP. This article describes the use of the Honan balloon to reduce the IOP before an intravitreal triamcinolone acetonide injection instead of the other procedures described in the literature, which may increase the risk of complications. The results of the technique in 19 patients with retinal vein occlusion are reported. Honan balloon was applied at 30 mm Hg for 10 minutes and the injection was then performed no more than 5 minutes after the removal of the Honan balloon. In no more than 10 minutes, this procedure resulted in a significant reduction in IOP. No complications such as central retinal artery occlusion were observed after the injection. 相似文献
22.
Enrique Barbieri 《Optimal control applications & methods.》1994,15(1):35-48
The two-stage synthesis of a multi-input/multi-output optimal proportional-integral (PI) controller is described for linear, time-invariant systems. In the first stage the PI controller is designed by solving a steady state algebraic Riccati equation. As a result, the optimal cost is expressed in terms of the system's constant output set-points. In the second stage the cost is further reduced by optimally selecting the output set-points to minimize a static quadratic performance index subject to linear algebraic constraints. The design framework is applied to a planar redundant robotic manipulator equipped with four joints and mounted at the tip of a long flexible arm. We then address the problem of self-motion control in the presence of vibratory disturbances. 相似文献
23.
24.
Francisco Camacho Juan Ferrando Antonio R. Pichardo Ismael Sotillo Enrique Jorquera 《Pediatric dermatology》1993,10(1):54-57
Abstract: A 20-year-old woman and her 12-year-old brother had hypohidrotic ectodermal dysplasia, cleft lip and palate, midfacial hypoplasia with narrow nose from the nasal bridge to the tip, narrow dysplastic nails, and conical teeth and hypodontia, and hypospadias and hypoplastic uvula in the boy. The woman had major underdevelopment of intellectual capacity. The most important hair anomalies in both siblings were sparse eyebrows, pili torti, and pili canaliculi. Some of the pili canaliculi had two canals (pili bicanaliculi), and the cross section for scanning electron microscopy had a quadrangular aspect. This is the seventh family reported with Rapp-Hodgkin ectodermal dysplasia. 相似文献
25.
The authors describe the different "retentive complexes" proposed by the Akers, Roach and Ney schools and analyse their biomechanical validity. 相似文献
26.
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
27.
Intestinal microvillous disorders are an uncommon cause of severe diarrhea, with very poor prognosis. The authors report the case of a female infant with Down syndrome, aganglionic megacolon, severe diarrhea, and jejunal biopsy with ultrastructural changes consistent with microvillous atrophy. The patient condition improved after a colostomy performed in the setting of the treatment of Hirschprung disease. 相似文献
28.
Robert A. Kinsman Enrique Fernandez Marsha Schocket Jerald F. Dirks Nicholas A. Covino 《Journal of behavioral medicine》1983,6(4):339-357
Subjective symptoms and experiences were explored within a group of 146 severe, chronic bronchitis and emphysema patients. Eighty-nine symptoms and experiences, derived from initial interviews with 29 patients, were rated according to the frequency of occurrence during breathing difficulties. Key cluster analyses were used to derive a Bronchitis-Emphysema Symptom Checklist (BESC) measuring 11 symptom categories: Helplessness-Hopelessness, Decathexis, Fatigue, Poor Memory, Peripheral-Sensory Complaints, Dyspnea, Congestion, Sleep Difficulties, Irritability, Anxiety, and Alienation. The BESC symptom categories are highly reliable and the relationships among categories are stable across two subgroups of patients. The BESC provides one way to describe how patients cope with and experience chronic bronchitis and emphysema. 相似文献
29.
Jin YP Fishbein MC Said JW Jindra PT Rajalingam R Rozengurt E Reed EF 《Human immunology》2004,65(4):291-302
Anti-human leukocyte antigen (HLA) antibodies (Ab) have long been implicated in the process of acute and chronic allograft rejection, yet their mechanism(s) of action is not well understood. The aim of this study was to determine whether ligation of HLA class I molecules by anti-HLA Ab on the surface of human endothelial cells (EC) activates the PI3 Kinase (PI3K)/Akt signaling pathway and downstream target proteins of the cell death apparatus. We report that Ab ligation of major histocompatibility complex (MHC) class I molecules on the surface of EC triggers phosphorylation of Akt, PI3K, and recruitment of PI3K and Akt into a signaling unit with focal adhesion kinase. Signaling through class I also stimulated phosphorylation of Bad and upregulated expression of Bcl-2 and Bcl-xL. Pretreatment of EC with the PI3K inhibitor wortmannin blocked class I-mediated expression of Bcl-2, but not Bcl-xL, suggesting a role for the PI3K/Akt signaling pathway in regulation of class I-induced Bcl-2 expression. The intracellular events initiated by class I ligation were influenced by the concentration of the anti-HLA Ab with the lowest tested concentrations of Ab stimulating the highest level of Akt phosphorylation, Bcl-xL and Bcl-2 expression. Consistent with the in vitro experiments, analysis of biopsy samples from heart transplant recipients with evidence of Ab-mediated rejection exhibited increased Bcl-2 expression on the vascular endothelium. These results suggest that exposure of the graft endothelium to low concentrations of anti-HLA Ab may promote cell survival by transducing signals resulting in upregulation of cell survival genes. 相似文献
30.
Holger Arndt Paul Kubes Matthew B. Grisham Enrique Gonzalez D. Neil Granger 《Inflammation》1992,16(5):549-559
The objective of this study was to determine the turnover rate of the extravascular pool of granulocytes in different regions of the feline gastrointestinal tract. Leukocyte emigration from the vasculature was prevented over a 48-h period by repeated intravenous injections of a monoclonal antibody (MAb IB4) directed against the leukocyte adhesion glycoprotein complex CD11/CD18. Tissue-associated myeloperoxidase (MPO) activity was used to monitor the total tissue granulocyte pool at 0.5, 12, 24, and 48 h after MAb IB4 administration. The mucosal layer of the duodenum, jejunum, ileum, and colon exhibited different kinetics of granulocyte clearance, with average life-spans (t1/2) ranging between 6.9 (colon) and 10.4 h (duodenum). Granulocyte clearance rates of 0.5 × 106 and 2.4 x 106 cells/h/g tissue were estimated (from measured values oft1/2 and tissue granulocyte pool) for the small bowel and colonie mucosae, respectively. The submucosal layer of the intestine exhibited a biphasic reduction in tissue MPO activity following immunoneutralization of CD11/CD18, with an initialt1/2 0.5 h followed by at1/2 of 36–60 h. The initial rapid decline in tissue MPO suggests that a significant fraction of granulocytes in the submucosa is localized in a readily exchangeable pool (e.g., marginated cells within the vasculature). The results of this study indicate that the average life-span of resident granulocytes varies significantly between different regions of the gastrointestinal tract, with the intestinal mucosa exhibiting at1/2 comparable to that previously reported for circulating feline neutrophils (R 8 h). 相似文献