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121.
Synthesized and directly acquired spin-echo images were compared in order to assess the validity of magnetic resonance (MR) image synthesis as a method enabling retrospective formation of images by interactive manipulation of scan parameters. Synthetic images subjectively compared favorably in both accuracy and precision with acquired images when formed for the same values of echo (TE) and repetition times (TR) and for interpolated and extrapolated values of both TE and TR. Plots of synthetic and acquired signals within the same pixel sectors quantitatively showed comparable values for several regions of interest in the brain. Percent error and noise-normalized differences between acquired and synthetic images were tested as a quantitative measure of accuracy. Percent error was consistently less than 5% for brain parenchyma, and synthetic signals were accurate to within four times the noise level at acquisition. The apparent signal-to-noise ratio of synthetic images was comparable, superior, or inferior to similar acquired images, depending on the values of TE and TR. Total acquisition time required for synthetic formation of images for arbitrary values of TE and TR was equivalent to that of a single direct acquisition with a TR of 2,500 msec. 相似文献
122.
During a 20-month period, fractures of the clivus occurring after craniocerebral trauma were diagnosed with computed tomography (CT) in 11 patients. Five patients had longitudinally oriented fractures; these were fatal in four patients due to either vertebral-basilar artery occlusion, brain stem trauma, or both. Six other patients had transversely oriented fractures that extended through the carotid canal and petrous temporal bone. While less frequently contributing directly to mortality, transverse fractures were also associated with cerebrospinal fluid leaks (two patients) and a cavernous sinus-carotid fistula (one patient). They were not as frequently associated with Horner syndrome or cranial nerve deficits as suggested in the current literature. This retrospective evaluation reveals two distinct injury patterns that demonstrate a difference in related morbidity and mortality. 相似文献
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125.
Ocular complications of orbital venography 总被引:1,自引:0,他引:1
126.
90K/Mac-2 binding protein is expressed in prostate cancer and induces promatrilysin expression 总被引:1,自引:0,他引:1
BACKGROUND: 90K/Mac-2 binding protein is a cell adhesive protein whose level of expression has been correlated with metastatic potential in many different tumor types. The purpose of this investigation was to examine 90K expression in prostate cancer and to determine a possible role for 90K in cancer progression. METHODS: 90K expression in prostate cell lines and tissue samples was evaluated by immunohistochemistry. Expression in cell lines was also evaluated by Western blot analysis and real-time RT-PCR. Induction of promatrilysin by 90K was evaluated by ELISA. RESULTS: Some of the human prostate cell lines studied expressed 90K. 90K was over-expressed in 38.8% of prostate cancer tumor samples, 7.14% of PIN lesions, and 18.6% of normal tissue. 90K was also shown to induce promatrilysin expression in the prostate cell line, LNCaP. CONCLUSIONS: These data demonstrate that 90K is over-expressed in a large fraction of malignant tumors. The fact that 90K can induce expression of promatrilysin indicates a possible role for 90K in cancer progression and metastasis. This suggests that 90K over-expression may be a useful marker for examining prostate cancer progression. 相似文献
127.
Ivascu FA Janczyk RJ Junn FS Bair HA Bendick PJ Howells GA 《The Journal of trauma》2006,61(2):318-321
BACKGROUND: Preinjury warfarin anticoagulation has been shown to increase the mortality of traumatic intracranial hemorrhage. We have evaluated the impact on patient mortality of the rapid triage of patients at risk for warfarin associated traumatic intracranial hemorrhage. METHODS: A "Coumadin Protocol" was implemented in January, 2001 in the Emergency Department that expedited triage of anticoagulated trauma patients to immediate physician evaluation. Patient outcomes during a 2 year period were compared with a matched control group of similarly injured, anticoagulated patients who were treated before protocol initiation. RESULTS: Thirty-five patients were treated after implementation of the Coumadin Protocol. Mean time until warfarin reversal was 4.3 +/- 4.4 hours, and there was a 37% mortality. Twenty-two control patients had a mean time to reversal of 4.2 +/- 2.9 hours, with a 45% mortality (p = 0.610). Ten protocol patients were shown to have intracranial hemorrhage progression by computed tomography (CT) scan, with a 60% mortality rate. Seventeen patients had follow-up CT scan and showed no progression; only one of these patients (6%) died (p = 0.004). Hemorrhage severity based on the initial CT scan did not predict mortality or hemorrhagic progression. CONCLUSIONS: We conclude from these data that a trauma center protocol for rapid identification of intracranial bleeding without a concomitant therapeutic protocol does not improve survival in head injured patients on preinjury warfarin. 相似文献
128.
BACKGROUND: It is well established that subjects participating in controlled clinical trials may not be representative of patients seen in actual practice. Given that efficacy and safety of sertraline have been investigated almost exclusively in controlled clinical trials, the aim of this study was to investigate efficacy, safety, and predictors of treatment response to sertraline in routine clinical practice. METHODS: A total of 1878 depressed outpatients (69.5% female; mean age, 50.3 years) participated in this prospective, open-label, non-interventional, postmarketing surveillance study of sertraline. The primary study outcome was change in depression severity as assessed independently with the Patient Health Questionnaire (PHQ-9) depression scale and Clinical Global Impression (CGI) scales after 12 weeks of treatment. Stepwise logistic regression analyses were used to identify independent predictors of treatment response. RESULTS: Using standard criteria to define clinical improvement, responder rates were 87.7% (PHQ-9) and 87.2% (CGI), respectively. Remission, i.e. a PHQ-9 score of 5 or below, occurred in 56.9% of patients. Independent baseline predictors of CGI treatment response were: non-chronic course of depression (OR=2.8, p < 0.001), non-psychiatric treatment setting (OR=2.5, p < 0.001), absence of comorbid physical disease (OR=1.9, p < 0.001), depression-related work disability (OR=1.9, p < 0.001), and no previous antidepressant medication (OR=1.5, p=0.03). Adverse events were reported by 4.8% of patients. LIMITATIONS: Lack of a control group limits the conclusions that can be drawn from this study. CONCLUSIONS: For treatment of depressive disorders in routine outpatient settings, sertraline is safe and efficacious. Patients without prior episodes of depression, without medical comorbidity, and those with higher levels of depression-related functional limitations are most likely to respond to sertraline treatment. 相似文献
129.
Ronnow BS Reyna SP Muhlestein JB Horne BD Allen Maycock CA Bair TL Carlquist JF Kfoury AG Anderson JL Renlund DG;International Heart Collaborative Study Group 《Cardiology》2005,104(4):196-201
C-reactive protein (CRP) has been associated with atherosclerotic complications, and we hypothesized that CRP levels might also predict death in non-ischemic patients with left ventricular dysfunction. Two hundred and three patients with non-ischemic left ventricular dysfunction undergoing cardiac catheterization were included and were followed for 2.4 +/- 1.4 years to determine the incidence of fatal events. Death occurred in 15% of patients with low CRP (1st and 2nd tertiles) and 30% of patients with high CRP (3rd tertile). After adjustment for 11 covariates, high CRP (p = 0.037, hazard ratio = 2.0) significantly and independently predicted mortality. Even in the absence of coronary artery disease, patients with left ventricular dysfunction are at increased risk of mortality based on their baseline CRP concentrations. 相似文献
130.