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61.
Kader AK  Tamboli P  Luongo T  Matin SF  Bell K  Jonasch E  Swanson DA  Wood CG 《The Journal of urology》2007,177(3):855-60; discussion 860-1
PURPOSE: Cytoreductive nephrectomy as part of a multidisciplinary approach may be considered in patients with metastatic renal cell carcinoma. The benefit in the elderly population (75 years or older) is unclear. We reviewed our experience to help determine if it is of benefit in this patient population. MATERIALS AND METHODS: Of 404 patients undergoing cytoreductive nephrectomy from 1995 and 2005 we identified 24 elderly patients. Outcomes in these elderly patients were analyzed and compared to outcomes in the remaining 380 who were younger than 75 years. RESULTS: Median age in the elderly and younger groups was 77.5 and 57.0 years, respectively. Performance status, sex distribution, and tumor histology, stage, grade and size were comparable. Estimated blood loss, transfusion rates, surgical times and hospital stay were similar in the 2 groups. There were 5 perioperative deaths (21%) in elderly patients compared to 4 (1.1%) in younger patients (p<0.01). Estimated blood loss, units transfused and surgical time were greater in the patients who died perioperatively (p<0.05). Median survival was 16.6 months in the elderly group, which did not differ statistically from the 13.7 months in the younger group. CONCLUSIONS: Cytoreductive nephrectomy in the elderly population can be associated with the potential for significant morbidity and mortality. Despite this and as part of a multidisciplinary approach it may provide potential survival as well as other benefits, which may justify it in highly select and highly motivated patients who are 75 years or older. However, it must be performed carefully with realistic expectations on behalf of the patient and urologist.  相似文献   
62.
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   
63.
CONTEXT: In Jews of Moroccan descent (MJ), the prevalence of steroid 11beta-hydroxylase deficiency (11-OHD) is relatively high, with a carrier rate estimated as approximately one in 40. A single mutation in the CYP11B1 gene (encoding 11beta-hydroxylase), R448H, was suggested to account for the disease alleles in this population. STUDY SUBJECTS: We screened 236 healthy MJ for R448H. RESULTS: Only two of the subjects screened were found to be carriers, suggesting that the R448H allele frequency is lower than was assumed previously. An R448H/R448C compound heterozygote patient, diagnosed with 11-OHD, was identified. However, a subsequent screen of MJ subjects for R448C failed to detect any carriers, suggesting that this was a private mutation of this family. CONCLUSION: The high incidence of 11-OHD in MJ, therefore, is only partially explained by the presence of R448H as a founder mutation.  相似文献   
64.
OBJECTIVE: To use the Minimum Data Set (MDS) to derive a risk-adjustment model for pressure ulcer development that may be used in assessing the quality of nursing home care. DESIGN: Perspective observational study using MDS data from 1997. SETTING: A large, for-profit, nursing home chain. PARTICIPANTS: Our unit of analysis was 39,649 observations made on 14,607 nursing home residents who were without a stage 2 or larger pressure ulcer on an index assessment. MEASUREMENTS: Pressure ulcer status was determined at an outcome assessment approximately 90 days after an index assessment. Potential predictors of pressure ulcer development were examined for bivariate associations, contributing to the development of a multivariate logistic regression model. RESULTS: A stage 2 or larger pressure ulcer developed in 2.3% of the observations. Seventeen resident characteristics were found to be associated with pressure ulcer development. These included dependence in mobility and transferring, diabetes mellitus, peripheral vascular disease, urinary incontinence, lower body mass index, and end-stage disease. A risk-adjustment model based on these characteristics was well calibrated and able to discriminate among residents with different levels of risk for ulcer development (model c-statistic = 0.73). CONCLUSION: A clinically credible risk-adjustment model with good performance properties can be developed using the MDS. This model may be useful in profiling nursing homes on their rate of pressure ulcer development.  相似文献   
65.
OBJECTIVE: To validate a previously derived risk-adjustment model for pressure ulcer development in a separate sample of nursing home residents and to determine the extent to which use of this model affects judgments of nursing home performance. DESIGN: Retrospective observational study using Minimum Data Set (MDS) data from 1998. SETTING: A large, for-profit, nursing home chain. PARTICIPANTS: Twenty-nine thousand and forty observations were made on 13,457 nursing home residents who were without a pressure ulcer on an index assessment. MEASUREMENTS: We used logistic regression in our validation sample to calculate new coefficients for the 17 previously identified predictors of pressure ulcer development. Coefficients from this new sample were compared with those previously derived. Expected rates of pressure ulcer development were determined for 108 nursing homes. Unadjusted and risk-adjusted rates of pressure ulcer development from these homes were also calculated and outlier identification using these two approaches was compared. RESULTS: Predictors of pressure ulcer development in the derivation sample generally showed similar effects in the validation sample. The model c-statistic was also unchanged at 0.73, but it was not calibrated as well in the validation sample. On applying the model to the nursing homes, expected rates of ulcer development ranged from 1.1% to 3.2% (P <.001). The observed rates ranged from 0% to 12.1% (P <.001). There were 12 outliers using unadjusted rates and 15 using adjusted performance. Ten nursing homes were identified as outliers using both approaches. CONCLUSIONS: Our MDS risk-adjustment model for pressure ulcer development performed well in this new sample. Nursing homes differ significantly in their expected rates of pressure ulcer development. Outlier identification also differs depending on whether unadjusted or risk-adjusted performance is evaluated.  相似文献   
66.
Objective Understanding the biological mediators involved in the complex inflammatory response of sepsis and acute lung injury offers the possibility of future investigations targeting treatment based on these mediators. This study investigated whether macrophage activator -glucan has a protective effect on acute lung injury in an experimental model of sepsis.Design and setting Experimental study in an experimental research center.Materials 30 rats randomized into three groups (sham, sepsis, and -glucan).Interventions Cecal ligation and puncture were performed in the -glucan and sepsis groups. The -glucan group was given a single intraperitoneal dose of -glucan (4 mg/kg) following cecal ligation.Measurements and results Rats treated with -glucan had fewer circulating neutrophils, more blood monocytes, and higher serum interleukin 6 levels than septic animals. The percentages of neutrophils and lymphocytes from the bronchoalveolar lavage fluid and the myeloperoxidase activity measured in the lung tissue were lower in the -glucan group than in the sepsis group. Less alveolar hemorrhage and neutrophil infiltration were observed in lungs from animals in the -glucan group in the septic groups.Conclusions In this rat model of intra-abdominal sepsis -glucan treatment partially protected against secondary lung injury, decreased lung hemorrhages, and lung neutrophilia. These results suggest that -glucan protects against sepsis-associated lung damage.  相似文献   
67.
Neuropsychological data about the forms of acquired reading impairment provide a strong basis for the theoretical framework of the dual-route cascade (DRC) model which is predictive of reading performance. However, lesions are often extensive and heterogeneous, thus making it difficult to establish precise functional anatomical correlates. Here, we provide a connective neural account in the aim of accommodating the main principles of the DRC framework and to make predictions on reading skill. We located prominent reading areas using fMRI and applied structural equation modeling to pinpoint distinct neural pathways. Functionality of regions together with neural network dissociations between words and pseudowords corroborate the existing neuroanatomical view on the DRC and provide a novel outlook on the sub-regions involved. In a similar vein, congruent (or incongruent) reliance of pathways, that is reliance on the word (or pseudoword) pathway during word reading and on the pseudoword (or word) pathway during pseudoword reading predicted good (or poor) reading performance as assessed by out-of-magnet reading tests. Finally, inter-individual analysis unraveled an efficient reading style mirroring pathway reliance as a function of the fingerprint of the stimulus to be read, suggesting an optimal pattern of cerebral information trafficking which leads to high reading performance.  相似文献   
68.
Clinical guidelines for the treatment of patients with non‐ST‐segment elevation myocardial infarction (NSTEMI) recommend an invasive strategy with cardiac catheterization, revascularization when clinically appropriate, and initiation of dual antiplatelet therapy regardless of whether the patient receives revascularization. However, although patients with NSTEMI have a higher long‐term mortality risk than patients with ST‐segment elevation myocardial infarction (STEMI), they are often treated less aggressively; with those who have the highest ischemic risk often receiving the least aggressive treatment (the “treatment‐risk paradox”). Here, using evidence gathered from across the world, we examine some reasons behind the suboptimal treatment of patients with NSTEMI, and recommend approaches to address this issue in order to improve the standard of healthcare for this group of patients. The challenges for the treatment of patients with NSTEMI can be categorized into four “P” factors that contribute to poor clinical outcomes: patient characteristics being heterogeneous; physicians underestimating the high ischemic risk compared with bleeding risk; procedure availability; and policy within the healthcare system. To address these challenges, potential approaches include: developing guidelines and protocols that incorporate rigorous definitions of NSTEMI; risk assessment and integrated quality assessment measures; providing education to physicians on the management of long‐term cardiovascular risk in patients with NSTEMI; and making stents and antiplatelet therapies more accessible to patients.  相似文献   
69.
BACKGROUND: There are widespread concerns regarding the quality of nursing home care and whether care is improving. We evaluated a large provider of nursing home care to determine whether risk-adjusted rates of pressure ulcer development have changed. METHODS: We used the Minimum Data Set to study National HealthCare Corporation nursing homes from 1991 through 1995. Rates of pressure ulcer development were calculated for successive 6-month periods by determining the proportion of residents initially ulcer-free having a stage 2 or larger pressure ulcer on subsequent assessments. Rates were risk-adjusted for patient characteristics. The proportion of new ulcers that were deep (stages 3 or 4) were also calculated. RESULTS: We examined risk-adjusted rates of pressure ulcer development based on 144,379 observations of 30,510 residents at 107 nursing homes. The number of observations per 6-month period ranged from 11,041 to 15,805. Between 1991 and 1995, there was a significant (P<.05) rate decline of more than 25%. Additionally, the proportion of new ulcers that were stages 3 or 4 declined from 30 to 22% (P<.01). CONCLUSIONS: Nursing homes showed significant improvement in the quality of pressure ulcer preventive care from 1991 to 1995.  相似文献   
70.
OBJECTIVES: New methods developed to improve the statistical basis of provider profiling may be particularly applicable to nursing homes. We examine the use of Bayesian hierarchical modeling in profiling nursing homes on their rate of pressure ulcer development. DESIGN: Observational study using Minimum Data Set data from 1997 and 1998. SETTING: A for-profit nursing home chain. PARTICIPANTS: Residents of 108 nursing homes who were without a pressure ulcer on an index assessment. MEASUREMENTS: Nursing homes were compared on their performance on risk-adjusted rates of pressure ulcer development calculated using standard statistical techniques and Bayesian hierarchical modeling. RESULTS: Bayesian estimates of nursing home performance differed considerably from rates calculated using standard statistical techniques. The range of risk-adjusted rates among nursing homes was 0% to 14.3% using standard methods and 1.0% to 4.8% using Bayesian analysis. Fifteen nursing homes were designated as outliers based on their z scores, and two were outliers using Bayesian modeling. Only one nursing home had greater than a 50% probability of having a true rate of ulcer development exceeding 4%. CONCLUSIONS: Bayesian hierarchical modeling can be successfully applied to the problem of profiling nursing homes. Results obtained from Bayesian modeling are different from those obtained using standard statistical techniques. The continued evaluation and application of this new methodology in nursing homes may ensure that consumers and providers have the most accurate information regarding performance.  相似文献   
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