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101.
Daniel L. Rubin Karen L. Falk Malcolm J. Sperling Michael Ross Sanjay Saini Barry Rothman Frank Shellock Elias Zerhouni David Stark Eric K. Outwater Udo Schmiedl Louis C. Kirby Judith Chezmar Terry Coates Miles Chang Jeffery M. Silverman Neil Rofsky Keith Burnett Julie Engel Stuart W. Young 《Journal of magnetic resonance imaging : JMRI》1997,7(5):865-872
The purpose of this study was to assess the effectiveness and safety of Gadolite Oral Suspension as a gastrointestinal (GI) contrast agent for MRI in a phase II and two phase III multicenter clinical trials. Gadolite was administered to 306 patients with known or suspected abdominal and/or pelvic disease. MRI with T1- and T2-weighted sequences was performed before and after ingestion. Efficacy was evaluated by having two masked readers rate the certainty of their MR diagnosis (0 = uncertain, 1 = probable, 2 = definite) on randomly presented pre- and post-Gadolite Oral Suspension enhanced images. Principal investigators also evaluated the images and established the final diagnosis. Vital signs, clinical chemistries, and adverse events were documented. Blood and urine samples were analyzed for gadolinium content to determine whether Gadolite Oral Suspension was absorbed systemically. Certainty in MR diagnosis increased significantly (P < .001) for both blinded readers between pre- and post-Gadolite images (.49–1.18 for reader 1; .46–1.53 for reader 2). Sensitivity, specificity, and accuracy also increased for both masked readers. No gadolinium was detected in blood or urine samples. There were no serious adverse events and no apparent drug-related trends in mean vital signs or laboratory values. Gadolite is a highly effective, safe, and well tolerated contrast agent for clinical use with MRI. 相似文献
102.
103.
104.
105.
James R. Boyce Peter D. Waite Patrick J. Louis Timothy J. Ness 《Journal canadien d'anesthésie》2003,50(10):1056-1060
PURPOSE: Fibreoptic intubation (FOI) has become an essential technique in the anesthetic management of patients with difficult airways. Unfortunately, residents may graduate from anesthesiology training programs with insufficient skills in FOI. To enhance resident proficiency at FOI without compromising patient comfort or safety, the technique of transnasal jet ventilation-assisted FOI was developed. This report describes our initial experience with this technique. METHODS: Sixty-four patients scheduled for oromaxillofacial surgery under nasal endotracheal anesthesia were recruited. Twenty-eight residents at all levels of training performed FOI through the patient's right nostril after the induction of general anesthesia and neuromuscular blockade. Oxygenation and ventilation were maintained by a faculty anesthesiologist using a Sanders device to deliver a jet of oxygen through a nasal trumpet placed in the patient's left nostril. The time from induction until completion of the FOI was recorded. Residents were subsequently queried about the educational benefit of the technique using a standardized questionnaire. RESULTS: All residents were able to successfully intubate all patients in this study. Thirteen residents successfully performed intubations on three or more occasions with 70% performing the technique faster on the third trial than on the first. No evidence of hypoxemia, gastric distension, pneumothorax, hemodynamic instability or recall was observed. All respondents to the questionnaire reported that the technique was useful as an educational tool and recommended its use with other residents. CONCLUSION: Transnasal jet ventilation-assisted FOI is a useful method to train residents in FOI while maximizing patient comfort and safety. 相似文献
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107.
Jordi Ortiz Lawrence W. Fitzgerald Maura Charlton Sarah Lane Louis Trevisan Xavier Guitart William Shoemaker Ronald S. Duman Eric J. Nestler 《Synapse (New York, N.Y.)》1995,21(4):289-298
In previous studies, we have demonstrated that chronic administration of morphine or cocaine produces some common biochemical adaptations in the ventral tegmental area (VTA) and nucleus accumbens (NAc), components of the mesolimbic dopamine system implicated in the reinforcing actions of these and other drugs of abuse. Since this neural pathway is also implicated in the reinforcing actions of ethanol, it was of interest to determine whether chronic ethanol exposure results in similar biochemical adaptations. Indeed, as seen for chronic morphine and cocaine treatments, we show here that chronic ethanol treatment increased levels of tyrosine hydroxylase and glial fibrillary acidic protein immunoreactivity, and decreases levels of neurofilament protein immunoreactivity, in the VTA. Also like morphine and cocaine, ethanol increases levels of cyclic AMP-dependent protein kinase activity in the NAc. These actions of ethanol required long-term exposure to the drug, and were in most cases not seen in the substantia nigra or caudate-putamen, components of the nigrostriatal dopamine system studied for comparison. Altered levels of tyrosine hydroxylase in catecholaminergic cells frequently reflect altered states of activation of the cells. Moreover, increasing evidence indicates that ethanol produces many of its acute effects on the brain by regulating NMDA glutamate and GABA receptors. We therefore examined the influence of chronic ethanol treatment on levels of expression of specific glutamate and GABA receptor subunits in the VTA. It was found that long-term, but not short-term, ethanol exposure increased levels of immunoreactivity of the NMDARl subunit, an obligatory component of NMDA glutamate receptors, and of the Glu Rl subunit, a component of many AMPA glutamate receptors; but at the same time, long-term ethanol exposure decreased immunoreactivity levels of the α1 subunit of the GABAA receptor complex. These changes are consistent with an increased state of activation of VTA neurons inferred from the observed increase intyrosine hydroxylase (TH) expression. These results demonstrate that chronic ethanol exposure results in several biochemical adaptations in the mesolimbic dopamine system, which may underlie prominent changes in the structural and functional properties of this neural pathway related to alcohol abuse and alcoholism. © 1995 Wiley-Liss, Inc. 相似文献
108.
Louis G. Martin M.D. Randy D. Cork James O. Wells 《Cardiovascular and interventional radiology》1993,16(2):76-80
Two hundred forty-four consecutive patients (mean age 61 years), including 123 who had technically valid renal vein renin
(RVR) analysis and 121 without RVR data, underwent technically successful percutaneous renal artery angioplasty (PTRA). They
were retrospectively examined to evaluate the utility of RVR analysis in identifying renal hypertension (RVH), predicting
benefit from PTRA, and determining if the lack of knowledge of renin levels significantly affected clinical outcome after
PTRA. Abnormal RVR values were associated with clinical benefit after PTRA in 62 of 93 patients (67% sensitivity, 20% specificity,
72% positive predictive value). Clinical improvement following PTRA occurred in 31 of 37 patients with normal pre-PTRA RVR
values (16% negative predictive value). RVR analysis correctly identified 86 of 117 patients with renovascular hypertension
(74% sensitivity, 16% negative predictive value). Improved blood pressure (BP) control occurred in 72% with abnormal RVR analysis
and 66% of the 121 patients without RVR data (p>0.1). We conclude that the very low negative predictive value significantly
limited the use of RVR analysis in this elderly (mean age 60 years) patient population with a high incidence of mild renal
functional impairment (mean serum creatinine 1.4 mg/dl) and bilateral renal artery stenosis (38%). The lack of pre-PTRA renin
data did not significantly affect clinical outcome. If RVR data were relied upon as the exclusive selection criterion in patients
of this type, many would be prevented from having the benefit of cure or improvement by PTRA. 相似文献
109.
110.
Dr. James G. Jarvis Aaron Marlow Louis J. Lawton William M. J. McIntyre 《Operative Orthopadie und Traumatologie》1998,10(2):117-124
Zusammenfassung
Operationsziel überdachung des Femurkopfes bei Hüftgelenkdysplasie.
Indikationen Dysplastisches Acetabulum bei Patienten mit neuromuskul?ren und nichtneuromuskul?ren Erkrankungen.
übergro?es, flaches Acetabulum.
Fehlen einer lateralen und kranialen überdachung.
Kontraindikationen Y-Fuge geschlossen, Wachstum abgeschlossen.
Stark verformter Femurkopf.
Operationstechnik Modifizierter Zugang nach Salter/Smith-Petersen. Freilegung und Teilung der Apophyse des Beckenkammes mit einem Messer. Freilegung
der Darmbeinschaufel. Osteotomie der ?u?eren Wand des Iliums; sie wird vorsichtig mit Hilfe eines gebogenen mei?els nach unten
gebogen und in dieser Stellung durch Einsetzen von trikortikalen Beckenkammsp?nen gehalten. Eine Osteosynthese ist nicht notwendig.
Becken-Bein-Gipsverband mit Einschlu? des gegenseitigen Oberschenkels für sechs Wochen.
Ergebnisse Zwischen 1987 und 1997 wurden 26 Hüften von 23 Patienten operiert. überwiegend handelte es sich um Kinder mit spastischen
Paresen. Folgende zus?tzliche Eingriffe wurden vorgenommen: Offene Reposition zehnmal, Femurosteotomie 18mal und Tenotomien
sowie Muskelabl?sungen 15mal. Der Durchschnittswert des azetabul?ren Index verbesserte sich von 32° auf 22°, der durchschnittliche
Wert des Kopfzentrum-Pfannenrand-Winkels von −25° auf 22° und der durchschnittliche Migrationsindex von 62% auf 69%. Als Komplikationen
wurden beobachtet: eine erneute Subluxation, ein frühzeitiger Verschlu? des Y-Knorpels, eine Fraktur des anderen Femur, einmal
heterotope Ossifikationen und einmal eine Infektion der Harnwege. 相似文献