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1.
We previously reported poorer survival among non-Hispanic blacks and Hispanics with idiopathic pulmonary fibrosis (IPF) compared to non-Hispanic whites at our center. In the current study, we hypothesized that these disparities would exist in a nationwide cohort of wait-listed patients with IPF. We performed a retrospective cohort study of 2635 patients with IPF listed for lung transplantation between 1995 and 2003 at 94 transplant centers in the United States. The age-adjusted mortality rate was higher among non-Hispanic blacks [hazard ratio (HR) = 1.24, 95% confidence interval (CI) 1.06-1.45, p = 0.009] and Hispanics (HR = 1.29, 95% CI 1.06-1.56, p = 0.01) compared to non-Hispanic whites. These findings persisted after adjustment for transplantation, medical comorbidities and socioeconomic status. Worse lung function at the time of listing appeared to explain some of these differences (HR for non-Hispanic blacks after adjustment for forced vital capacity percent predicted = 1.16, 95% CI 0.98-1.36, p = 0.09; HR for Hispanics = 1.21, 95% CI 0.99-1.48, p = 0.056). In summary, black and Hispanic patients with IPF have worse survival than whites after listing for lung transplant.  相似文献   
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Cognitive function was examined in 227 patients three months after admission to hospital for ischaemic stroke, and in 240 stroke-free controls, using 17 scored items that assessed memory, orientation, verbal skills, visuospatial ability, abstract reasoning, and attentional skills. After adjusting for demographic factors with standardised residual scores in all subjects, the fifth percentile was used for controls as the criterion for failure on each item. The mean (SD) number of failed items was 3.4 (3.6) for patients with stroke and 0.8 (1.3) for controls (p < 0.001). Cognitive impairment, defined as failure on any four or more items, occurred in 35.2% of patients with stroke and 3.8% of controls (p < 0.001). Cognitive domains most likely to be defective in stroke compared with control subjects were memory, orientation, language, and attention. Among patients with stroke, cognitive impairment was most frequently associated with major cortical syndromes and with infarctions in the left anterior and posterior cerebral artery territories. Functional impairment was greater with cognitive impairment, and dependent living after discharge either at home or nursing home was more likely (55.0% with, v 32.7% without cognitive impairment, p = 0.001). In a logistic model examining the risks related to dependent living after stroke, cognitive impairment was a significant independent correlate (odds ratio, OR = 2.4), after adjusting for age (OR = 5.2, 80 + v 60-70 years) and physical impairment (OR = 3.7, Barthel index < or = 40 v > 40). It is concluded that cognitive impairment occurs frequently after stroke, commonly involving memory, orientation, language, and attention. The presence of cognitive impairment in patients with strike has important functional consequences, independent of the effects of physical impairment. Studies of stroke outcome and intervention should take into account both cognitive and physical impairments.  相似文献   
4.
It has been reported that treatment with L-carnitine at a daily dose of 3 g orally may cause a rise in platelet aggregation and serum triglyceride concentration in hemodialyzed patients. The present double-blind cross-over study has been performed to evaluate the influence of L-carnitine when compared with placebo on platelet aggregation and plasma concentrations of various factors involved in platelet activation. In addition, the concentration of triglycerides, cholesterol and HDL-cholesterol has been evaluated. 18 uremic patients on maintenance hemodialysis for at least 1 year were randomly allocated either to a control group receiving placebo or to a group treated with L-carnitine. Statistical analysis performed by means of ANOVA did not show any significant change in the serum concentration of cholesterol, HDL-cholesterol and triglycerides. Furthermore, platelet aggregation tests (performed with adenosine 5'-diphosphate, epinephrine, thrombin and collagen) and plasma beta-thromboglobulin concentration did not show any statistically significant difference. In addition, the plasma concentration of several coagulation markers, such as factor VIIIc, antithrombin III, alpha 2-antiplasmin, and fibrinopeptide A, did not show any significant variation. The results suggest that under our experimental conditions L-carnitine neither increases the risk of thromboembolism nor alters the serum lipid content in uremic patients on chronic hemodialysis.  相似文献   
5.
The influence of the pre- and postweaning maternal environment on the offspring's phenotype was examined in 5-HT1A and 5-HT1B receptor knockout mice (KO1A and KO1B, respectively). We have previously shown that, when born to and raised by homozygous dams of the same genotype, adult KO1A are more anxious than wild-type (WT) mice, and adult KO1B are hyperactive and slightly less anxious than WT mice. We extend our studies here to the behavioral results of the offspring's own genotype, when the dam's genotype is constant, and the effects of the dam's genotype when the offspring's genotype is constant. In Experiments 1 and 2, KO1A-/- pups produced less ultrasonic vocalizations (USV) than controls in an isolation test on postnatal Day 7 when born to and reared by KO1A dams, either -/- or +/-. Heterozygous F1 pups reared by KO1A-/- dams produced more USV and were less anxious in the plus-maze at 2 to 3 months of age than F1 pups born to and reared by WT dams (Experiment 3). F1 pups reared by KO1B-/- dams produced less USV and were more anxious in the plus-maze than F1 pups reared by WT dams (Experiment 4). The results support a role for maternal effects that may comprise direct effects such as the dam's behavior and nutritional care of the pup, and possibly more complex indirect effects through the establishment of idiosyncratic dam-pup dyadic interactions. We recommend that breeding techniques that rely on same genotype (mutant-mutant or WT-WT) breeding pairs not be used to generate offspring when the focus of research is the study of gene function, but rather when familial effects need to be studied.  相似文献   
6.
Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation.  相似文献   
7.
Serum prostate specific antigen, prostate specific antigen density and free:total prostate specific antigen are known to be useful for determining the risk of prostate cancer in patients undergoing prostate cancer screening. The patient with a positive biopsy presents no future prostate specific antigen dilemma. Those with negative biopsies often go on to numerous repeat biopsies. Our goal was to establish criteria that could be used to identify patients who will require repeat prostate biopsies (possibly false negative initial biopsy), while not exposing the low risk population (probable true negative initial biopsy) to additional invasive procedures. Between March 1991 and March 1998, 148 patients who had a biopsy for an elevated prostate specific antigen value (4.1-10.0) or an altered digital rectal examination, had no cancer found in the specimen. From these, 51 (34.4%) had repeated biopsies, while the others persisted on close follow-up. We examined their serum prostate specific antigen, prostate specific antigen density and free:total prostate specific antigen value, as well as their age and histology results of the initial and repeat biopsy, to determine if any predictor of the need for a repeat biopsy could be identified. Eight (15.7%) from 51 men who had repeat biopsy had prostate cancer detected. Forty three (84.3%) patients persisted with a negative biopsy, despite filling the criteria for re-biopsy. Multivariate analysis failed to identify any significant predictors of prostate cancer in the repeat biopsy group. Despite initial success, the prostate specific antigen derivatives and free:total prostate specific antigen have not safely limited the number of biopsies performed for an abnormal prostate specific antigen (4.1-10.0). Neither prostate specific antigen density nor free:total prostate specific antigen predicted the need for repeat biopsy in this specific group. The results of this ongoing study demonstrate that to date, prostate specific antigen and prostate specific antigen derivatives can not be utilized to determine which patients will be at high risk for requiring repeat prostate biopsy. All patients must be closely monitored for evidence of a change in status from benign to malignant disease, and new markers for this purpose are urgently needed.  相似文献   
8.
PURPOSE: Trials have demonstrated decreased relapse with perioperative methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) chemotherapy in patients with muscle invasive bladder cancer. We evaluated whether the benefit of chemotherapy correlates with its effects on distant or pelvic relapse. MATERIALS AND METHODS: We retrospectively evaluated the records of all 107 patients who underwent cystectomy for muscle invasive bladder cancer at our institution between 1988 and 1994. Factors predicting relapse were identified and used to group patients at high or low risk. The outcome in each group with and without M-VAC chemotherapy was then analyzed in terms of overall, metastatic and pelvic relapse. Univariate analysis was performed using the Kaplan-Meier method and log rank statistic, and multivariate analysis was done using the Cox proportional hazards model. Median survival was 29 months for patients free of disease. RESULTS: Pathological stage T3 or greater according to the American Joint Committee on Cancer, tumor greater than 3 cm. and creatinine greater than 1.5-fold normal were independent poor prognostic factors in patients treated with cystectomy only. Patients with any of these factors or metastatic involvement of the pelvic lymph nodes were considered at high risk. All 35 low risk patients were treated with cystectomy only and had an excellent outcome with a 3-year relapse-free survival plus or minus standard error of 93% +/- 5%. The 3-year rates in 52 and 20 high risk patients treated without and with chemotherapy, respectively, were 42% +/- 8% versus 57% +/- 13% for relapse-free survival (p = 0.17), 38% +/- 9% versus 8% +/- 8% for pelvic failure (p = 0.02) and 39% +/- 9% versus 38% +/- 13% for distant metastases (not significant). Multivariate analysis of patients who underwent pelvic lymphadenectomy revealed that perioperative chemotherapy improved relapse-free survival and pelvic control but not metastatic control (p = 0.03, 0.02 and 0.31, respectively). CONCLUSIONS: Low risk patients have excellent disease control when treated with cystectomy only. Those with high risk features are at substantial risk for pelvic failure (38% at 3 years) after cystectomy only. Perioperative M-VAC chemotherapy has a profound impact on pelvic but not on metastatic failure.  相似文献   
9.

Objectives

The aims of the present study were: 1) to investigate the contribution of the extent of luminal stenosis and other lesion composition-related factors in predicting invasive fractional flow reserve (FFR); and 2) to explore the distribution of various combinations of morphological characteristics and the severity of stenosis among lesions demonstrating normal and abnormal FFR.

Background

In patients with stable ischemic heart disease, FFR-guided revascularization, as compared with medical therapy alone, is reported to improve outcomes. Because morphological characteristics are the basis of plaque rupture and acute coronary events, a relationship between FFR and lesion characteristics may exist.

Methods

This is a subanalysis of NXT (HeartFlowNXT: HeartFlow Analysis of Coronary Blood Flow Using Coronary CT Angiography), a prospective, multicenter study of 254 patients (age 64 ± 10 years, 64% male) with suspected stable ischemic heart disease; coronary computed tomography angiography including plaque morphology assessment, invasive angiography, and FFR were obtained for 383 lesions. Ischemia was defined by invasive FFR ≤0.80. Computed tomography angiography–defined morphological characteristics of plaques and their vascular location were used in univariate and multivariate analyses to examine their predictive value for invasive FFR. The distribution of various combinations of plaque morphological characteristics and the severity of stenosis among lesions demonstrating normal and abnormal FFR were examined.

Results

The percentage of luminal stenosis, low-attenuation plaque (LAP) or necrotic core volume, left anterior descending coronary artery territory, and the presence of multiple lesions per vessel were the predictors of FFR. When grouped on the basis of degree of luminal stenosis, FFR-negative lesions had consistently smaller LAP volumes compared with FFR-positive lesions. The distribution of plaque characteristics in lesions with normal and abnormal FFR demonstrated that whereas FFR-negative lesions excluded likelihood of stenotic plaques with moderate to high LAP volumes, only one-third of FFR-positive lesions demonstrated obstructive plaques with moderate to high LAP volumes.

Conclusions

In addition to the severity of luminal stenosis, necrotic core volume is an independent predictor of FFR. The distribution of plaque characteristics among lesions with varying luminal stenosis and normal and abnormal FFR may explain the outcomes associated with FFR-guided therapy.  相似文献   
10.
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