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101.
Abraham MT Bains MS Downey RJ Korst RJ Kraus DH 《The Annals of otology, rhinology, and laryngology》2002,111(8):667-671
Patients who undergo intrathoracic operative procedures for malignancy may require sacrifice of a recurrent laryngeal nerve. Postoperative vocal fold paralysis may lead to diminished cough with secretion retention, aspiration, and life-endangering pneumonia. This study retrospectively reviews our institution's experience of 23 patients who underwent type I thyroplasty within the 2-week (acute) period after thoracic surgery. Primary lung cancer (n = 16) was the most common disease. Upper lobectomy (n = 9) and pneumonectomy (n = 7) were the most frequent surgical procedures. Silicone medialization alone (n = 11) or with arytenoid adduction (n = 12) was performed. There were no significant postoperative complications. Improvements in hoarseness (86%), dyspnea (72%), dysphagia (50%), and aspiration (79%) were noted. Pulmonary status improved after vocal fold medialization, as reflected by decreased need for therapeutic bronchoscopy in the majority of patients in the postoperative period. Type I thyroplasty for vocal fold paralysis in the acute phase following thoracic surgery is well tolerated and is associated with improved patient outcome with no postoperative deaths in this high-risk patient population. 相似文献
102.
Clinical pattern and pathologic stage but not histologic features predict outcome for bronchioloalveolar carcinoma 总被引:11,自引:0,他引:11
Ebright MI Zakowski MF Martin J Venkatraman ES Miller VA Bains MS Downey RJ Korst RJ Kris MG Rusch VW 《The Annals of thoracic surgery》2002,74(5):1640-6; discussion 1646-7
BACKGROUND: The histologic criteria defining bronchioloalveolar carcinoma (BAC) were recently revised, but it is unclear whether these criteria predict clinical behavior. This study determined the outcome of resected BAC in relationship to clinical and radiologic disease pattern, and pathologic features. METHODS: Between 1989 and 2000, 100 consecutive surgically treated patients with adenocarcinomas exhibiting various degrees of BAC features were retrospectively studied. Histology was reviewed; tumors were classified as pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features. Clinical and radiologic pattern were classified as unifocal, multifocal, or pneumonic. Demographic data, tumor stage, and outcome were recorded. Survival was analyzed by the Kaplan-Meier method, and prognostic factors were determined by the log-rank test. RESULTS: Patient median age was 65, and 74% of the patients were female. Pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features occurred in 47, 21, and 32 patients, respectively. Unifocal disease occurred in 64 patients, multifocal in 29, and pneumonic in 7. Seventy-one patients had stage I/II tumors, 22 had stage III/IV, and 7 patients had Stage X tumors. Overall 5-year survival was 74%. There was no significant difference in survival among the three histologic subtypes. The pneumonic pattern had significantly worse survival compared with unifocal and multifocal patterns. Pathologic stage predicted survival, with 5-year survivals for I/II and III/IV of 83.7% and 59.6%, respectively. CONCLUSIONS: Clinical pattern and pathologic stage, but not the degree of invasion on histologic examination predict survival. Multifocal disease is associated with excellent long-term survival after resection. The favorable survival of stage III/IV BAC indicates that the current staging system does not fully describe this disease in patients undergoing resection because of its distinct tumor behavior. 相似文献
103.
Measurement of brain tissue oxygenation performed using positron emission tomography scanning to validate a novel monitoring method 总被引:8,自引:0,他引:8
Gupta AK Hutchinson PJ Fryer T Al-Rawi PG Parry DA Minhas PS Kett-White R Kirkpatrick PJ Mathews JC Downey S Aigbirhio F Clark J Pickard JD Menon DK 《Journal of neurosurgery》2002,96(2):263-268
OBJECT: The benefits of measuring cerebral oxygenation in patients with brain injury are well accepted; however, jugular bulb oximetry, which is currently the most popular monitoring technique used has several shortcomings. The goal of this study was to validate the use of a new multiparameter sensor that measures brain tissue oxygenation and metabolism (Neurotrend) by comparing it with positron emission tomography (PET) scanning. METHODS: A Neurotrend sensor was inserted into the frontal region of the brain in 19 patients admitted to the neurointensive care unit. After a period of stabilization, the patients were transferred to the PET scanner suite where C15O, 15O2, and H2(15)O PET scans were obtained to facilitate calculation of regional cerebral blood volume, O2 metabolism, blood flow, and O2 extraction fraction (OEF). Patients were given hyperventilation therapy to decrease arterial CO2 by approximately 1 kPa (7.5 mm Hg) and the same sequence of PET scans was repeated. For each scanning sequence, end-capillary O2 tension (PvO2) was calculated from the OEF and compared with the reading of brain tissue O2 pressure (PbO2) provided by the sensor. In three patients the sensor was inserted into areas of contusion and these patients were eliminated from the analysis. In the subset of 16 patients in whom the sensor was placed in healthy brain, no correlation was found between the absolute values of PbO2 and PvO2 (r = 0.2, p = 0.29); however a significant correlation was obtained between the change in PbO2 (deltaPbO2) and the change in PvO2 (deltaPvO2) produced by hyperventilation in a 20-mm region of interest around the sensor (p = 0.78, p = 0.0035). CONCLUSIONS: The lack of correlation between the absolute values of PbO2 and PvO2 indicates that PbO2 cannot be used as a substitute for PvO2. Nevertheless, the positive correlation between deltaPbO2 and deltaPvO2 when the sensor had been inserted into healthy brain suggests that tissue PO2 monitoring may provide a useful tool to assess the effect of therapeutic interventions in brain injury. 相似文献
104.
Nesheim M Samis J Walker J Becker L Brufatto N Fischer T Tejidor L Jones G Houdijk W Giles A Koschinsky M Wenstone R Downey C Toh CH 《Blood reviews》2002,16(Z1):S15-S22
The 'biphasic transmittance waveform' (BTW) refers to a decrease in light transmittance that often occurs prior to clotting in coagulation assays of critically ill patient plasmas. It correlates with disseminated intravascular coagulation and mortality. The present work shows that the BTW is due to the rapid formation of a precipitate and a coincident change in turbidity in re-calcified plasma. The precipitate was isolated from patient plasma and contained lipids typical of very low density lipoprotein (VLDL), plus the proteins apolipoprotein B-100 and C-reactive protein (CRP). Precipitation also occurred in normal plasma supplemented with CRP. In addition, CRP precipitated with VLDL and intermediate density lipoprotein, but not low density lipoprotein or high density lipoprotein. The Kd value for the CRP/VLDL interaction is 340 nM. The IC50 value of Ca2+ for complex formation is 5.0 mM, and epsilon-aminocaproic acid inhibits the process. In 15 plasmas with the BTW from critically ill patients, CRP was highly elevated (77-398 microg/mL) and VLDL cholesterol ranged from 0.082 to 1.32 mM. The magnitude of the turbidity change on re-calcification correlated well with the calculated level of the CRP/VLDL complex. Thus, the Ca2+-dependent formation of a complex between CRP and VLDL accounts for the BTW. 相似文献
105.
106.
107.
Wang LM Zhang Q Zhu W He C Lu CL Ding DF Chen ZY 《第二军医大学学报》2005,26(11):1299-1299
Glial cell line-derived neurotrophic factor (GDNF) plays a critical role in neurodevelopment and survival of midbrain dopaminergic and spinal motor neurons in vitro and in vivo. The biological actions of GDNF are mediated by a two-receptor complex consisting of a glycosylphosphatidylinositol-linked cell surface molecule, the GDNF family receptor alpha 1 (GFR alpha 1), and receptor protein tyrosine kinase Ret. Although structural analysis of GDNF has been extensively examined, less is known about the structural basis of GFR alpha 1 function. In this study, based on evolutionary trace method and relative solvent accessibility prediction of residues, a set of trace residues that are solvent-accessible was selected for site-directed mutagenesis. A series of GFR alpha 1 mutations was made, and PC12 cell lines stably expressing different GFR alpha 1 mutants were generated. According to the survival and differentiation responses of these stable PC12 cells upon GDNF stimulation and the GDNF- GFR alpha 1-Ret interaction assay, residues 152NN153, Arg259, and 316SNS318 in the GFR alpha 1 central region were found to be critical for GFR alpha 1 binding to GDNF and eliciting downstream signal transduction. The single mutation R259A in the GFR alpha 1 molecule simultaneously lost its binding ability to GDNF and Ret. However N152A/N153A or S316A/N317A/ S318A mutation in the GFR alpha 1 molecule still retained the ability to bind with Ret. These findings suggest that distinct structural elements in GFR alpha 1 may be involved in binding to GDNF and Ret. 相似文献
108.
CJT De Amorim e Silva A Mackenzie LM Hallowell SE Stewart MR Ditchfield 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):319-323
The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non‐GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non‐diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty‐four children undertook a practice MRI (age range 4.1–16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non‐GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital. 相似文献
109.
Psychoanalysis began as a depth psychology, heavily based on the sexual experiences and memories of patients. A long-term treatment, utilizing a free association method, psychoanalysis has provided a window onto the meanings and functions of fantasy, including sexual fantasy. Although psychoanalysis has produced some scientific research, the field has tended to rely on observational data collected from individuals studied in depth. Sex research on the other hand, carried out by investigators from different disciplines is based on empirical investigation. Each field has made contributions fundamentally important to the other. In this article, we review psychoanalytic ideas about human sexuality and distinguish those that have been invalidated by systematic research from those that remain useful. Perhaps, the single most important revision of psychoanalytic theory during the past century was concerned with the psychological development of girls and women. We separately discuss the development of the sexes, and stress the need for bridge building between psychoanalysis and sex research. 相似文献
110.