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排序方式: 共有350条查询结果,搜索用时 15 毫秒
1.
PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors.  相似文献   
2.
Candidate genes involved with androgen metabolism have been hypothesized to affect the risk of prostate cancer. To further investigate this, we evaluated the relationship between prostate cancer and multiple potentially functional polymorphisms in three genes involved in androgen metabolism: CYP1B1 (two single nucleotide polymorphisms: 355G/T and 4326C/G), prostate-specific antigen (PSA/KLK3 (three single nucleotide polymorphisms: -158A/G, -4643G/A, and -5412C/T), and CYP11alpha [(tttta)(n) repeat], using a moderately large (n = 918) sibling-based case-control population. When looking at all subjects combined, no association was observed between any polymorphism-or their haplotypes-and prostate cancer risk. However, among men with more aggressive prostate cancer, the CYP1B1 355G/T variant was positively associated with disease: carrying one or two T alleles gave odds ratios (OR) of 1.90 [95% confidence interval (95% CI), 1.09-3.31; P = 0.02] and 3.73 (95% CI, 1.39-10.0; P = 0.009), respectively. Similarly, carrying the CYP1B1 355T-4326C haplotype was positively associated with prostate cancer among men with high aggressive disease (P = 0.01). In addition, the PSA -158G/-158G genotype was positively associated with prostate cancer among men with less aggressive disease (OR, 2.71; 95% CI, 1.06-6.94; P = 0.04). Our findings suggest that CYP1B1 and PSA variants may affect the risk of prostate cancer and tumor aggressiveness.  相似文献   
3.
4.
BackgroundThere is controversy regarding the extent of aortic resection necessary in patients with aortopathy related to bicuspid aortic valve disease. To address this issue, we reviewed our experience in patients undergoing ascending aorta replacement during bicuspid aortic valve replacement.MethodsWe reviewed 702 patients who underwent ascending aorta replacement at the time of initial nonemergent native bicuspid aortic valve replacement at our institution between January 2000 and June 2017. Treatment cohorts included an open hemiarch replacement group (n = 225; 32%) and a clamped ascending aorta replacement group (n = 477; 68%).ResultsMedian patient age was 60 years (interquartile range [IQR], 51-67 years), female sex was present in 113 patients (16%), ejection fraction was 62% (IQR, 56%-66%), and aortic arch diameter was 33 mm (IQR, 29-36 mm). Cardiopulmonary bypass time was longer in the hemiarch replacement group (188 minutes vs 97 minutes; P < .001). Procedure-related complications (36%) and mortality (<1%) were similar in the 2 groups; however, the hemiarch group had an increased odds of blood transfusion (odds ratio, 1.62; 95% confidence interval [CI], 1.15-2.28; P = .006). The median duration of follow-up was 6.0 years (95% CI, 5.3-6.8 years). Overall survival was 94 ± 1% at 5 years and 80 ± 2% at 10 years. Multivariable analysis demonstrated similar survival in the 2 groups (hazard ratio, 0.83; 95% CI, 0.51-1.33; P = .439). No repeat aortic arch operations were done for aortopathy over the duration of clinical follow-up.ConclusionsCompared with patients in the clamped ascending aorta replacement group, patients in the hemi-arch replacement group had longer cardiopulmonary bypass and aortic cross-clamp times, along with an increased risk of blood transfusion, but similar freedom from repeat aortic arch operation and survival. We identified no advantage of performing hemiarch replacement in the absence of aortic arch dilation.  相似文献   
5.
Background Alopecia areata (AA) is an organ‐specific, T‐cell‐mediated autoimmune disease that is characterized by non‐scarring hair loss. Objective We aimed to find the factors that may affect the response to topical therapy in AA. Methods The study included a total of 60 patients with AA and 30 healthy control patients. The AA patients were randomized into two groups. 40 patients used 0.05% clobetasol propionate cream, and 20 patients used petrolatum (placebo). Both groups applied topical treatments to their lesions twice daily for 12 weeks. Results The mean extent of AA was 21.88 ± 16.75% in patients with autoantibodies and 12.16 ± 13.55% in those who were negative for autoantibodies (P = 0.021). Ophiasic pattern and nail involvement were observed more frequently in patients with atopy (P < 0.05). Relapse was more frequent in patients with atopy (P = 0.002) and nail involvement (P = 0.02). Conclusions We observed that the presence of autoantibodies was associated with more extensive AA, and that ophiasic hair loss pattern and nail dystrophy were significantly associated with atopy. Topical clobetasol propionate treatment produced a modest advantage in hair regrowth as compared with placebo. Notably, atopic AA patients have a higher risk of relapse and redevelopment of AA after completing a course of topical corticosteroid treatment.  相似文献   
6.
An ectopic thyroid gland results from the abnormal migration of the thyroid in the course of its development. Primary ectopic mediastinal thyroid is very rare and occurs in less than 1% of all goiters that can be surgically excised. Ectopic thyroid tissue has a characteristic sonographic appearance as smooth‐bordered, homogeneous, hypoechoic tissue with fine specular echoes. We report 3 cases of mediastinal ectopic thyroid diagnosed by endobronchial ultrasound‐guided transbrochial needle aspiration biopsy.  相似文献   
7.

Objective

This study explores the potential use of drones in searching for and locating victims and of motorized transportation of search and rescue providers in a mountain environment using a simulation model.

Methods

This prospective randomized simulation study was performed in order to compare two different search and rescue techniques in searching for an unconscious victim on snow-covered ground. In the control arm, the Classical Line Search Technique (CLT) was used, in which the search is performed on foot and the victim is reached on foot. In the intervention arm, the Drone-snowmobile Technique (DST) was used, the search being performed by drone and the victim reached by snowmobile. The primary outcome of the study was the comparison of the two search and rescue techniques in terms of first human contact time.

Results

Twenty search and rescue operations were conducted in this study. Median time to arrival at the mannequin was 57.3 min for CLT, compared to 8.9 min for DST. The median value of the total searched area was 88,322.0 m2 for CLT and 228,613.0 m2 for DST. The median area searched per minute was 1489.6 m2 for CLT and 32,979.9 m2 for DST (p < 0.01 for all comparisons).

Conclusions

In conclusion, a wider area can be searched faster by drone using DST compared to the classical technique, and the victim can be located faster and reached earlier with rescuers transported by snowmobile.  相似文献   
8.
Purpose

Hypophysitis is a heterogeneous condition that includes inflammation of the pituitary gland and infundibulum, and it can cause symptoms related to mass effects and hormonal deficiencies. We aimed to evaluate the potential role of machine learning methods in differentiating hypophysitis from non-functioning pituitary adenomas.

Methods

The radiomic parameters obtained from T1A-C images were used. Among the radiomic parameters, parameters capable of distinguishing between hypophysitis and non-functioning pituitary adenomas were selected. In order to avoid the effects of confounding factors and to improve the performance of the classifiers, parameters with high correlation with each other were eliminated. Machine learning algorithms were performed with the combination of gray-level run-length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray-level co-occurrence entropy.

Results

A total of 34 patients were included, 17 of whom had hypophysitis and 17 had non-functioning pituitary adenomas. Among the 38 radiomics parameters obtained from post-contrast T1-weighted images, 10 tissue features that could differentiate the lesions were selected. Machine learning algorithms were performed using three selected parameters; gray level run length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray level co-occurrence entropy. Error matrices were calculated by using the machine learning algorithm and it was seen that support vector machines showed the best performance in distinguishing the two lesion types.

Conclusions

Our analysis reported that support vector machines showed the best performance in distinguishing hypophysitis from non-functioning pituitary adenomas, emphasizing the importance of machine learning in differentiating the two lesions.

  相似文献   
9.
Elevated uric acid (UA) levels have been associated with cardiovascular disease in epidemiologic studies. The relation between UA levels and long-term outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention is not known. Data from 2,249 consecutive patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were evaluated. Patients were divided into 2 groups with high or low UA using upper limits of normal of 6 mg/dl for women and 7 mg/dl for men. There were 1,643 patients in the low-UA group (mean age 55.9 ± 11.6 years, 85% men) and 606 patients in the high-UA group (mean age 60.5 ± 12.6 years, 76% men). Serum UA levels were 8.0 ± 1.5 mg/dl in the high-UA group and 5.2 ± 1.0 mg/dl in the low-UA group (p <0.001). The in-hospital mortality rate was significantly higher in patients with high UA levels (9% vs 2%, p <0.001), as was the rate of adverse outcomes in patients with high UA. The mean follow-up time was 24.3 months. Cardiovascular mortality, reinfarction, target vessel revascularization, heart failure, and major adverse cardiac events were all significantly higher in the high-UA group. In a multivariate analyses, high plasma UA levels were an independent predictor of major adverse cardiac events in the hospital (odds ratio 2.03, 95% confidence interval 1.25 to 3.75, p = 0.006) and during long-term follow-up (odds ratio 1.64, 95% confidence interval 1.05 to 2.56, p = 0.03). In conclusion, high UA levels on admission are independently associated with in-hospital and long-term adverse outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention.  相似文献   
10.
Fever of unknown origin (FUO) is a diagnostic challenge for the practising physician. Detailed medical history, physical examination, non-invasive laboratory tests, and radiologic examinations compose the first level in the diagnostic approach to the FUO. When a diagnosis cannot be established with these procedures, some invasive diagnostic techniques and finally exploratory laparotomy are performed. Although advanced diagnostic measures and imag-ing-guided less invasive procedures have decreased the need, laparotomy remains as a final diagnostic method for FUO cases. In this study we evaluate the role and importance of laparotomy in the diagnosis of our FUO cases. In 17 out of 126 patients (8 male, 9 female, the median age 35.8 years) hospitalized in our clinic between 1982 and 2002 with the diagnosis of FUO, the diagnosis was established by laparotomy. The diagnosis was made directly in 13 patients, and indirectly (by excluding other diseases) in 2 patients. In several FUO series, the contribution of laparotomy to the diagnosis of FUO was reported as 27-100%. This rate was found to be 88% in the present study. During laparotomy on 17 cases, tissue samples were taken from spleen, liver, intra-abdominal and mesenteric lymph nodes. Pathologic examination of these tissue samples revealed miliary tuberculosis in 4; non-Hodgkin’s lymphoma in 3; Hodgkin’s lymphoma in 3; liver tumour in 1; hairy cell leukemia in 1; peritonitis carcinomatosis in 1. In the patients with miliary tuberculosis, the liver (3) and/or spleen (2), and/or lymph node (3) revealed caseating granulomas. Laparotomy diagnosed 3 of 5 cases whose abdominal ultrasonography and computerized tomography were normal. In conclusion, although advanced diagnostic methods decreased the need for laparotomy in FUO, if non-invasive and invasive diagnostic measures fail, laparotomy may contribute to the diagnosis. The selection of the patient and the timing are important for laparotomy.  相似文献   
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