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AC Unger H Cabrera-Palacios AP Schulz Ch Jürgens A Paech 《European journal of medical research》2009,14(6):264-271
Introduction
At present there are no reliable non-traumatic and non-invasive methods to analyse the healing process and loosening status after total hip replacement. Therefore early as well as late loosening of prosthesis and interface component problems are difficult to be found or diagnosed at any time.Methods
In a cadaver study the potential application of Resonance Frequency Monitoring (RFM) will be evaluated as a non-invasive and non-traumatic method to monitor loosening and interface problems in hip replacement. In a 65 year old female cadaver different stability scenarios for a total hip replacement (shaft, head/modular head and cup, ESKA, Luebeck, Germany) are simulated in cemented and cement less prosthesis and then analysed with RFM. The types of stability vary from secure/press-fit to interface-shaft disruption.Results
The RFM shows in cemented as well as cement less prosthesis significant intra-individual differences in the spectral measurements with a high dynamic (20 dB difference corresponding to the factor 100 (10000%)), regarding the simulated status of stability in the prosthesis system.Conclusion
The results of the study demonstrate RFM as a highly sensitive non-invasive and non-traumatic method to support the application of RFM as a hip prosthesis monitoring procedure. The data obtained shows the possibility to use RFM for osteointegration surveillance and early detection of interface problems, but will require further evaluation in clinical and experimental studies. 相似文献74.
EM Maier J Pongratz AC Muntau B Liebl U Nennstiel-Ratzel U Busch R Fingerhut B Olgemöller AA Roscher W Röschinger 《Clinical genetics》2009,76(2):179-187
Medium‐chain acyl‐CoA dehydrogenase deficiency (MCADD) represents a potentially fatal fatty acid β‐oxidation disorder. Newborn screening (NBS) by tandem mass spectrometry (MS/MS) has been implemented worldwide, but is associated with unresolved questions regarding population heterogeneity, burden on healthy carriers, cut‐off policies, false‐positive and negative rates. In a retrospective case‐control study, 333 NBS samples showing borderline acylcarnitine patterns but not reaching recall criteria were genotyped for the two most common mutations (c.985A>G/c.199C>T) and compared with genotypes and acylcarnitines of 333 controls, 68 false‐positives, and 34 patients. c.985A>G was more frequently identified in the study group and false‐positives compared to controls (1:4.3/1:2.3 vs. 1:42), whereas c.199C>T was found more frequently only within the false‐positives (1:23). Biochemical criteria were devised to differentiate homozygous (c.985A>G), compound heterozygous (c.985A>G/c.199C>T), and heterozygous individuals. Four false‐negatives were identified because our initial algorithm required an elevation of octanoylcarnitine (C8) and three secondary markers in the initial and follow‐up sample. The new approach allowed a reduction of false‐positives (by defining high cut‐offs: 1.4 μmol/l for C8; 7 for C8/C12) and false‐negatives (by sequencing the ACADM gene of few suspicious samples). Our validation strategy is able to differentiate healthy carriers from patients doubling the positive predictive value (42→88%) and to target NBS to MCADD‐subsets with potentially higher risk of adverse outcome. It remains controversial, if NBS programs should aim at identifying all subsets of all diseases included. Because the natural course of milder variants cannot be assessed by observational studies, our strategy could serve as a general model for evaluation of MS/MS‐based NBS. 相似文献
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Fleischer AC; Dudley BS; Entman SS; Baxter JW; Kalemeris GC; James AE Jr 《Radiology》1987,162(2):307-310
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion. 相似文献
77.
Jens Vogel-Claussen Jan Skrok Elliot K Fishman João AC Lima Ashish S Shah David A Bluemke 《Journal of cardiothoracic surgery》2009,4(1):42-5
We report the case of a 67 year-old patient who presented with worsening chest pain and shortness of breath, four days post
acute myocardial infarction. Contrast enhanced computed tomography of the chest ruled out a pulmonary embolus but revealed
an unexpected small subepicardial aneurysm (SEA) in the lateral left ventricular wall which was confirmed on cardiac magnetic
resonance imaging. Intraoperative palpation of the left lateral wall was guided by the cardiac MRI and CT findings and confirmed
the presence of focally thinned and weakened myocardium, covered by epicardial fat. An aneurysmorrhaphy was subsequently performed
in addition to coronary bypass surgery and a mitral valve repair. The patient was discharged home on post operative day eight
in good condition and is feeling well 2 years after surgery. 相似文献
78.
Use of Temporary Enteral Access Devices in Hospitalized Neonatal and Pediatric Patients in the United States 下载免费PDF全文
Beth Lyman MSN RN CNSC Carol Kemper PhD RN CPHQ LaDonna Northington DNS RN Jane Anne Yaworski MSN RN Kerry Wilder BSN RN MBA Candice Moore BSN RN CPN Lori A. Duesing MSN RN CPNP‐AC Sharon Irving PhD RN 《JPEN. Journal of parenteral and enteral nutrition》2016,40(4):574-580
Background: Temporary enteral access devices (EADs), such as nasogastric (NG), orogastric (OG), and postpyloric (PP), are used in pediatric and neonatal patients to administer nutrition, fluids, and medications. While the use of these temporary EADs is common in pediatric care, it is not known how often these devices are used, what inpatient locations have the highest usage, what size tube is used for a given weight or age of patient, and how placement is verified per hospital policy. Materials and Methods: This was a multicenter 1‐day prevalence study. Participating hospitals counted the number of NG, OG, and PP tubes present in their pediatric and neonatal inpatient population. Additional data collected included age, weight and location of the patient, type of hospital, census for that day, and the method(s) used to verify initial tube placement. Results: Of the 63 participating hospitals, there was an overall prevalence of 1991 temporary EADs in a total pediatric and neonatal inpatient census of 8333 children (24% prevalence). There were 1316 NG (66%), 414 were OG (21%), and 261 PP (17%) EADs. The neonatal intensive care unit (NICU) had the highest prevalence (61%), followed by a medical/surgical unit (21%) and pediatric intensive care unit (18%). Verification of EAD placement was reported to be aspiration from the tube (n = 21), auscultation (n = 18), measurement (n = 8), pH (n = 10), and X‐ray (n = 6). Conclusion: The use of temporary EADs is common in pediatric care. There is wide variation in how placement of these tubes is verified. 相似文献
79.
Impact of Early Initiation of Enteral Nutrition on Survival During Pediatric Extracorporeal Membrane Oxygenation 下载免费PDF全文
Kristin C. Greathouse MS CPNP‐AC Kelly T. Sakellaris MS RD Dmitry Tumin PhD Jacob Katsnelson MD Joseph D. Tobias MD Don Hayes MD Jr. Andrew R. Yates MD 《JPEN. Journal of parenteral and enteral nutrition》2018,42(1):205-211
Introduction: Pediatric data related to safety, tolerance, and outcomes of enteral nutrition (EN) for patients requiring extracorporeal membrane oxygenation (ECMO) are lacking. The objectives of this study were to evaluate early nutrition status and timing of EN initiation on survival during pediatric ECMO. Methods: A single center institutional review board–approved retrospective chart review was performed on all pediatric patients requiring ECMO from October 2008 through December 2013. Demographics, ECMO variables, laboratory values, vasoactive inotropic score (VIS), and nutrition data on day 5 (d5) were collected. Patients receiving parenteral nutrition (PN) were compared with those receiving any EN on d5. Analyses were conducted to identify factors influencing survival to completion of ECMO and to discharge. Results: Forty‐nine patients aged 53 ± 76 months met inclusion criteria. Kaplan‐Meier curves demonstrated greater survival to discharge in patients receiving any EN, compared with only receiving PN (P = .031). EN on d5 of ECMO support (P = .040) and a higher percentage of daily energy intake achieved (P = .013) were protective, whereas a higher VIS was associated with increased mortality (P = .010). Multivariable analysis demonstrated EN was no longer associated with survival to discharge (P = .139), whereas energy intake (P = .021) and VIS (P = .013) remained significant. Conclusions: Pediatric patients who received nutrition that was closer to goal energy intake, as well as those who received any EN early during ECMO, had improved survival to hospital discharge. 相似文献
80.