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排序方式: 共有519条查询结果,搜索用时 515 毫秒
91.
92.
Serial Lead Impedance Measurements Confirm Fixation of Helical Screw Electrodes During Pacemaker Implantation 总被引:2,自引:0,他引:2
MARC ROELKE ALAN D. BERNSTEIN VICTOR PARSONNET 《Pacing and clinical electrophysiology : PACE》2000,23(4):488-492
The purpose of this study was to determine whether serial measurements of helical screw pacemaker lead impedance could reliably confirm electrode fixation in the right atrium and right ventricle. Fixation is generally assessed fluoroscopically, which can be misleading because the myocardium is radio lucent. Alternatively, because the electrical conductivity of blood is greater than that of myocardium, serial measurements of the lead impedance might be expected to show an impedance increase with appropriate fixation of the pacemaker electrode when the electrode becomes embedded in myocardial tissue. Impedance measurements were made during the placement of 23 atrial and 28 ventricular active fixation electrodes in 31 consecutive patients. Impedance measurements were recorded in unipolar and bipolar electrode configurations with the electrode free floating in the chamber, unfixed (with exposed screws) but touching the endocardial surface, and after fixation. No significant impedance differences were found between free-floating and unfixed electrode positions. With fixation, the lead impedance increased significantly in the ventricle (P = 0.0001, unipolar and bipolar) and the atrium (P = 0.0069 unipolar and 0.0052 bipolar). Typical increases, reflected by median values, were 197 ohms unipolar and 203 ohms bipolar in the ventricle and 47 ohms unipolar and 53 ohms bipolar in the atrium for electrodes with permanently exposed or retractable screw designs. Comparing serial measurements of lead impedance before and after electrode fixation is a valid electrical method of confirming appropriate fixation of helical screw electrodes. 相似文献
93.
JUDITH RANKIN CHRISTINE CANS ESTER GARNE ALLAN COLVER HELEN DOLK PETER ULDALL EMMANUELLE AMAR INGEBORGE KRAGELOH‐MANN 《Developmental medicine and child neurology》2010,52(4):345-351
Aim Our aim was to determine the proportion of children with cerebral palsy (CP) who have a congenital anomaly (CA) in three regions (Isère Region, French Alps; Funen County, Denmark; Northern Region, England) where population‐based CP and CA registries exist, and to classify the children according to CA subtype. Method Data for children born between 1991 and 1999 were linked using electronic matching of cases. All potential matches were checked manually by each centre and verified as true matches. Results A total of 1104 children with CP were born during the study period (663 males, 441 females). Of these, 166 (15%; 95% Confidence Interval [CI] 13.0–17.3) children with CP had a CA: 8.8% had a cerebral anomaly, 4.8% had a non‐cerebral anomaly, and 1.4% had a non‐cerebral‐related syndrome or a chromosomal/genetic anomaly. Interpretation The prevalence of cerebral anomaly was highest in children with ataxic CP (41.7%) and lowest in those with dyskinetic CP (2.1%). Cerebral anomalies were found in 8.4% and 7% of children with bilateral and unilateral spastic CP respectively. The most frequent cerebral anomalies were primary microcephaly (26.5%) and congenital hydrocephalus (17.3%). The most common non‐cerebral anomalies recorded were cardiac (12.6% of children with CP and CA), urinary (5.4%), and musculoskeletal (5.4%). The prevalence of cerebral anomalies was higher among children born at term (13%) than among those born preterm (3.8%). Associated sensorineural or intellectual impairments occurred more often in children with CP and cerebral anomalies. We concluded that cerebral and non‐cerebral CA prevalence was higher among the CP population than in the general population of live births. 相似文献
94.
95.
ALAN D. BERNSTEIN A. JOHN CAMM JOHN D. FISHER ROSS D. FLETCHER R. HARDWIN MEAD ANTHONY W. NATHAN VICTOR PARSONNET ANTHONY F. RICKARDS NICHOLAS P.D. SMYTH RICHARD SUTTON PETER P. TARJAN 《Pacing and clinical electrophysiology : PACE》1993,16(9):1776-1780
A new generic code, patterned after and compatible with the NASPE/BPEG Generic Pacemaker Code (NBG Code) was adopted by the NASPE Board of Trustees on January 23. 1993. It was developed by the NASPE Mode Code Committee, including members of the North American Society of Pacing and Electrophysiology (NASPE) and the British Pacing and Electrophysiology Croup (BPEC). It is abbreviated as the NBD (for NASPE/BPEC Defibrillator) Code. It is intended for describing the capabilities and operation of implanted cardioverter defibrillators (ICDs) in conversation, record keeping, and device labeling, and incorporates four positions designating: (1) shock location; (2) antitachycardia pacing location; (3) means of tachycardia detection; and (4) antibradycardia pacing location. An additional Short Form, intended only for use in conversation, was defined as a concise means of distinguishing devices capable of shock alone, shock plus antibradycardia pacing, and shock plus antitachycardia and antibradycardia pacing. 相似文献
96.
JUDITH A. TREVAN-HAWKE 《Australian Occupational Therapy Journal》1986,33(3):114-120
The development and assessment of body image distortion in relation to physical and psychosocial dysfunction is discussed in relation to the validity of psychomotor, psychodynamic and behavioural approaches. A literature search of treatment procedures reveals that to date no single approach can be considered more reliable or valid than any other in body image disturbance. 相似文献
97.
ISABELLA L. KARLE JUDITH L. FLIPPEN-ANDERSON MUPALLA SUKUMAR PADMANABHAM BALARAM 《Chemical biology & drug design》1988,31(6):567-576
The structures of two crystal forms of Boc-Trp-Ile-Ala-Aib-Ile-Val-Aib-Leu-Aib-Pro-OMe have been determined. The triclinic form (PI, Z= l) from DMSO/H2O crystallizes as a dihydrate (Karle, Sukumar & Balaram (1986) Proc. Natl. Acad. Sci. USA 83, 9284-9288). The monoclinic form (P21, Z = 2) crystallized from dioxane is anhydrous. The conformation of the peptide is essentially the same in both crystal systems, but small changes in conformational angles are associated with a shift of the helix from a predominantly α-type to a predominantly 310-type. The r.m.s. deviation of 33 atoms in the backbone and Cβ positions of residues 2-8 is only 0.29 Å between molecules in the two polymorphs. In both space groups, the helical molecules pack in a parallel fashion, rather than antiparallel. The only intermolecular hydrogen bonding is head-to-tail between helices. There are no lateral hydrogen bonds. In the P21 cell, a = 9.422(2)Å, b = 36.392(11)Å, c = 10.548(2)Å, β= 111.31(2)° and V = 3369.3Å3 For 2 molecules of C60H97N11O10 per cell. 相似文献
98.
Opposing views as to the validity of body image disturbance as a diagnostic criterion for anorexia nervosa are discussed in relation to diagnosis, prognosis, and the treatment mode. The various methods used to assess body image disturbance are examined and a recommendation that the occupational therapy literature should be investigated to enable a proposal for treatment of the more severe instances of anorexia nervosa. 相似文献
99.
JUDITH LUMLEY J. F. CORREY † N.M. NEWMAN J.T. CURRAN 《Journal of paediatrics and child health》1985,21(1):13-14
An analysis of all births in Tasmania from 1975 to 1983 showed that social class differences in low birth weights were almost entirely restricted to infants between 1500 and 2500 g weight at birth. There was a marginal increase in very low birth weight infants (<1500 g) among women whose partners were unemployed or in unskilled work but extremely low birth weight infants (<1000 g) were evenly distributed across the whole social spectrum. 相似文献