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71.
Comparisons of nomograms and urologists' predictions in prostate cancer   总被引:4,自引:0,他引:4  
When applying nomograms to a clinical setting it is essential to know how their predictions compare with clinicians'. Comparisons exist outside of the prostate cancer literature. We reviewed these comparisons and conducted 2 experiments comparing predictions of clinicians with prostate cancer nomograms. By using Medline, we searched studies from January 1966 to July 1999 that compared human predictions with nomogram predictions. Next, we conducted 2 experiments: (1) 17 urologists were presented with 10 case vignettes and asked to predict the 5-year recurrence-free probabilities for each patient; (2) case presentations of 63 prostate cancer patients (including full clinical histories with complete diagnostic data and surgical findings) were made to a group of 25 clinicians who were asked to predict organ-confined disease. We found 22 published studies comparing human experts with nomograms, greater than half (13 of 22) showed the nomogram performing above the level of the human expert. Our first experiment showed urologist modification of 165 nomogram predictions led to a decrease in prediction accuracy (c-index decreased from.67 to.55, P <.05). In our second experiment, clinician predictions of organ-confined disease were comparable to the nomogram (area under the receiver operating characteristic curve [AUC] 0.78 and 0.79, respectively). A mixed-model suggests the nomogram did not augment clinician prediction accuracy (doctor excess error 1.4%, P =.75, 95% confidence interval [CI]: -10.9% to 8.2%). Our data suggest that nomograms do not seem to diminish predictive accuracy and they may be of significant benefit in certain clinical decision making settings.  相似文献   
72.
BACKGROUND: Recently, iterative reconstruction with segmented attenuation corrections (IRSAC) has been introduced for reconstruction of (18)F-FDG PET images. IRSAC produces images that are more pleasing to the eye, but qualitative and quantitative comparisons between IRSAC and filtered back projection (FBP) have not been reported for metastatic cancer. Since quantitative data has been widely used as an adjunct to interpretation of PET scans, comparison between IRSAC and FBP is needed. The purpose of this study was to compare image quality and the maximum standardized uptake value (SUVmax) obtained with FBP and with IRSAC in metastatic lesions from prostate cancer. METHODS: Twenty (18)F-FDG PET scans (10 baseline and 10 follow-up) were performed in 10 patients with prostate cancer (ages 66-85 yrs, mean 73.6 yrs). Acquisition began 45 min after injection of 370 MBq of (18)F-FDG. Images were reconstructed using FBP and IRSAC, and submitted to visual and quantitative analysis. SUVmax was obtained for all metastases, on FBP and IRSAC. A Jaszczak phantom study was also performed. RESULTS: IRSAC images showed better image quality than FBP especially in regions of high activity concentrations. IRSAC detected 106 lesions on both baseline and follow-up scans, while FBP detected 100 and 95 lesions on baseline and follow-up scans, respectively. Therefore, 17 more lesions were seen on IRSAC. The mean SUVmax values on baseline scans for FBP and IRSAC were systematically different, at 4.46+/-1.99 and 5.13+/-2.67, respectively. On follow-up scans values were 3.89+/-1.72 for FBP and 4.29+/-1.93 for IRSAC. Comparison of FBP with IRSAC on baseline and follow-up scans were statistically significant (baseline: paired "t"-test p=0.0017; follow-up: paired "t"-test p=0.0008). Phantom studies reveal that these differences can be explained by the type of reconstruction filters used, and IRSAC was more accurate than FBP. CONCLUSIONS: IRSAC detects smaller volumes in phantoms, patient images are easier to interpret and more metastatic lesions were detected. In addition, IRSAC provides reproducible quantitative data, comparable to data provided by FBP. IRSAC SUV and FBP SUV are in close agreement but there was a statistically significant difference between the two, and therefore threshold values of SUV will probably need to be re-determined with IRSAC, and are likely to be 10 to 19% higher than currently reported.  相似文献   
73.
Association between epidural analgesia and intrapartum fever   总被引:2,自引:0,他引:2  
The objective of this paper is to determine whether or not epidural analgesia is an independent risk factor for intrapartum fever. Maternal temperature was measured every 4 h during labor to 1004 consecutive women in term labor. Women with fever or on antibiotics were excluded. Epidural analgesia was administered upon patients' request. Of the 406 (40%) women who received epidural analgesia, 11.8% (n = 48) developed a fever > or = 37.8 degrees C during labor compared with only 0.2% (n = 1) of women not receiving epidural analgesia. Women who received epidural analgesia were more likely to have one or more risk factors for intrapartum infection. Their labor and ruptured membranes were longer, they were more likely to have internal monitoring and have more vaginal examinations. Compared with women who received epidural analgesia and did not develop intrapartum fever, women that did develop fever had longer epidurals and more risk factors for infection. However, in a logistic regression analysis with fever as dependent variable, only the duration of epidural was significantly associated with the occurrence of fever. The rate of fever increased with longer labors, from 5% with labor < 3 h to 28% with labor > 6 h. In 90% of women the fever resolved within a few hours after delivery. Sepsis evaluation was negative in all of the newborns to mother who had intrapartum fever. Our data support a noninfectious etiology for intrapartum fever in the vast majority of our patients. However, infection must be ruled out before a decision is made to withhold antibiotic therapy.  相似文献   
74.
75.
Intrapartum drainage of fetal pleural effusion   总被引:2,自引:0,他引:2  
Our objective was to describe our experience with intrapartum thoracocentesis in fetuses with severe bilateral pleural effusion. We describe the outcome of four consecutive cases of fetal pleural effusion due to chylothorax that were managed by intrapartum thoracocentesis. These fetuses were not candidates for pleuro-amniotic shunting either because of the need for prompt delivery (three fetuses) or because of advanced gestational age (one fetus). Thoracocentesis was performed in the operating theatre under ultrasound guidance prior to Caesarean delivery. Gestational age at the time of diagnosis and thoracocentesis ranged between 26-34 weeks and 31-34 weeks respectively. Bilateral thoracocentesis was performed in two fetuses and unilateral in the remaining two fetuses. All four infants were born in a relatively good condition; however, all eventually required intubation, ventilation and chest tubes. Chest tubes were introduced between 2 h and 5 days after delivery in three infants, and immediately after birth in one infant who was hydropic. Two infants survived and are developing normally. One infant died from sepsis following successful pleurodesis and one from aspiration on day 51. Our conclusions are that intrapartum thoracocentesis seems to be a relatively simple procedure, that allows newborns with pleural effusion, to breathe spontaneously or be more easily ventilated. This in turn, reduces the need to introduce chest tubes in an emergency situation.  相似文献   
76.
77.
BACKGROUND: The aims of this study were to determine the presence of trefoil factor family-3 (TFF3) expression in biliary epithelial cells (BECs) of chronic graft-versus-host disease (cGVHD) of the liver after allogeneic hematopoietic cell transplantation, to compare such expression in chronic liver diseases (CLD) with/without predominantly biliary disease, and to assess the effect of bile duct injury on the degree of TFF3 expression in BECs of cGVHD. METHODS: A total of 82 paraffin-embedded liver biopsy samples were reviewed. These samples were basically divided into two distinct groups according to the presence of ductal injury: group 1 with CLD and predominantly biliary disease (n=26: 17 cGVHD and 9 primary biliary cirrhosis [PBC]) and group 2 with CLD and predominantly parenchymal liver disease (n=56: 20 steatohepatitis and 36 chronic viral hepatitis). Group 2 was used as the controls. Immunohistochemistry was performed using a polyclonal anti-TFF3 antibody. Real-time quantitative PCR was used for the detection of TFF3 mRNA expression. RESULTS: Positive TFF3 immunohistochemical staining and the presence of TFF3 messenger RNA gene expression was demonstrably higher in group 1 than that in group 2 (P<0.0001 and P<0.05, respectively). No significant difference in terms of positive TFF3 stained BECs between GVHD and PBC samples was observed (P>0.05). The extent of TFF3 expression in GVHD samples with severe ductal injury were significantly more common than that of GVHD samples with mild/moderate ductal injury (P<0.0001). CONCLUSIONS: The expression of TFF3 in cGVHD of the liver is increased in response to bile duct damage and repair. Such expression seems to be related the severity of ductal injury.  相似文献   
78.
On October 9-11, 2003, the third meeting of the White Matter Study Group of the International Society for Magnetic Resonance in Medicine was held in Venice, Italy. This article is the report of the meeting on how to use MRI in the diagnostic workup of multiple sclerosis (MS) and allied white matter disorders, and to define the nature and the extent of MS pathology in vivo. Both of these steps are central to the design of future treatment strategies aimed at limiting the functional consequences of the most disabling aspects of this disease.  相似文献   
79.
80.
BACKGROUND: It is not clear if more intense surveillance is associated with improved survival after curative resection for cancer. In the context of a followup program after curative gastrectomy, recurrence and survival were investigated for patients presenting with either symptomatic or asymptomatic recurrence. STUDY DESIGN: A prospectively maintained gastric cancer database was used to identify all patients who underwent a curative (R0) gastrectomy from July 1985 to June 2000. Survival curves were generated for patients with either symptomatic or asymptomatic recurrence, and the prognostic variables associated with outcomes were identified. RESULTS: Of 1,172 patients who underwent a curative (R0) gastrectomy, 561 patients (48%) had documented recurrence and 382 patients had complete data about symptoms. Median time to recurrence was 10.8months for asymptomatic patients and 12.4months for symptomatic patients (p = NS). Median postrecurrence survival was 13.5months for asymptomatic patients and 4.8months for symptomatic patients (p < 0.01). Median disease-specific survival was 29.4months for asymptomatic patients and 21.6months for symptomatic patients (p < 0.05). Variables predictive of poor postrecurrence survival included symptomatic recurrence, advanced stage (III/IV), poor differentiation, short disease-free interval (<12months), and multiple sites of recurrence. CONCLUSIONS: Followup did not identify asymptomatic recurrence earlier than symptomatic recurrence. Patients with symptomatic recurrence have more aggressive disease with a shorter postrecurrence survival. The impact of detecting asymptomatic recurrence in the course of followup after curative gastrectomy could not be distinguished from the effects of four powerful biologic variables that also interact to govern outcomes.  相似文献   
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