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991.
Yelamanchili P Nanda NC Patel V Baysan O Singh A Duncan K Rajdev S Brown ML 《Echocardiography (Mount Kisco, N.Y.)》2006,23(8):704-706
We describe two adult patients with left ventricular noncompaction in whom live/real time three-dimensional transthoracic echocardiography (3DTTE) supplemented two-dimensional transthoracic echocardiography in making a definitive diagnosis of clots coexisting with trabeculations in the left ventricle. Mobility of clots and the presence of central echolucencies consistent with clot lysis were best demonstrated by 3DTTE and served to confidently differentiate clots from adjacent trabeculations. 相似文献
992.
Patel MR Chen AY Roe MT Ohman EM Newby LK Harrington RA Smith SC Gibler WB Calvin JE Peterson ED 《The American journal of medicine》2007,120(1):40-46
Purpose
Although adherence to guidelines recommendations is assumed to be more difficult for nonacademic community hospitals, patterns of adherence have not been evaluated by hospital type. We sought to identify hospital characteristics associated with high levels of adherence in order to gain insight into successful processes of care.Methods
From January 2001 through March 2004, we analyzed data from 86,042 patients in the CRUSADE Initiative with high-risk non-ST-segment elevation acute coronary syndromes (NSTE ACS) defined by positive cardiac markers or ischemic ST-segment changes. Academic sites were defined by Council of Teaching Hospital affiliation in the American Hospital Association database. Adherence was determined for each hospital based on guidelines recommendations for the use of 4 acute (<24 hrs) and 5 discharge therapies in patients without contraindications. Multivariable modeling was used to standardize hospital estimates for patient characteristics and control for clustering within centers.Results
A total of 60,285 patients were admitted to nonacademic hospitals (n = 355), and 25,757 were admitted to academic hospitals (n = 125). Academic hospitals were larger (median 500 vs 268 beds, P <.001) and more often had bypass services (88% vs 60%, P <.001). Composite adherence to recommended therapies was slightly higher at academic vs. nonacademic hospitals (median 77.8% vs 73.7%, P <0.01), and variance in individual hospital performance was greater among nonacademic sites. Nonacademic hospitals accounted for 15 of the 20 highest performing sites and 19 of the 20 lowest performing sites. In-hospital clinical outcomes, including cardiogenic shock, stroke, and death were similar for patients admitted to both types of hospital.Conclusion
Adherence to American College of Cardiology and American Heart Association (ACC/AHA) guidelines for NSTE ACS care at academic hospitals is slightly higher than at nonacademic hospitals; however there is significant room for improvement within both systems. The larger performance variation in care among nonacademic hospitals highlights the need for continued emphasis on consistent care processes. 相似文献993.
994.
New strategies for prevention and therapy of cytomegalovirus infection and disease in solid-organ transplant recipients 总被引:23,自引:0,他引:23 下载免费PDF全文
In the past three decades since the inception of human organ transplantation, cytomegalovirus (CMV) has gained increasing clinical import because it is a common pathogen in the immunocompromised transplant recipient. Patients may suffer from severe manifestations of this infection along with the threat of potential fatality. Additionally, the dynamic evolution of immunosuppressive and antiviral agents has brought forth changes in the natural history of CMV infection and disease. Transplant physicians now face the daunting task of recognizing and managing the changing spectrum of CMV infection and its consequences in the organ recipient. For the microbiology laboratory, the emphasis has been geared toward the development of more sophisticated detection assays, including methods to detect emerging antiviral resistance. The discovery of novel antiviral chemotherapy is an important theme of clinical research. Investigations have also focused on preventative measures for CMV disease in the solid-organ transplant population. In all, while much has been achieved in the overall management of CMV infection, the current understanding of CMV pathogenesis and therapy still leaves much to be learned before success can be claimed. 相似文献
995.
Gordon W. Selling Atanu Biswas Alpa Patel Dennis J. Walls Christopher Dunlap Yen Wei 《Macromolecular chemistry and physics.》2007,208(9):1002-1010
Zein fibers have been produced by electrospinning from acetic acid, aqueous methanol, ethanol and isopropyl alcohol. Alcohol solutions produced fibers that were predominantly ribbons. Fibers spun from acetic acid solution have a round morphology with a narrower distribution of diameters when spun under suitable conditions. The IR spectra of electrospun fibers display increased absorbance at 1 650 cm?1 relative to starting material, indicative of increased α‐helical structure. Raman spectra of fibers spun from acetic acid solution had spectral differences, having increased absorbance at 680, 750 and 860 cm?1, versus fibers spun from alcoholic solvents suggesting different tertiary structure within the fiber, which may result from different structures in solution. Polarized Raman spectroscopy taken parallel and perpendicular to the fiber axis displayed no differences, suggesting similar secondary and tertiary structures in these directions. All of the fibers had some degree of birefringence demonstrating the presence of orientation. The smaller fibers were highly birefringent throughout the fiber, while the larger fibers had orientation at the surface only. Quality fibers could not be produced from N,N‐dimethylformamide, acetone/water, acetic acid/water, 8 M urea/water or 10% NaOH/water zein solutions.
996.
Melanoma is a relentless type of skin cancer which involves myriad signaling pathways which regulate many cellular processes. This makes melanoma difficult to treat, especially when identified late. At present, therapeutics include chemotherapy, surgical resection, biochemotherapy, immunotherapy, photodynamic and targeted approaches. These interventions are usually administered as either a single-drug or in combination, based on tumor location, stage, and patients’ overall health condition. Howe... 相似文献
997.
Bryan Coburn Donald E. Low Samir N. Patel Susan M. Poutanen Dea Shahinas Alireza Eshaghi Barbara M. Willey Allison McGeer 《Journal of clinical microbiology》2014,52(5):1766-1767
We report the emergence of vancomycin resistance in a patient colonized with a vanA-containing, vanRS-negative isolate of Enterococcus faecium which was initially vancomycin susceptible. This is a previously undescribed mechanism of drug resistance with diagnostic and therapeutic implications. 相似文献
998.
Mansy HA Hoxie SJ Patel NH Sandler RH 《Medical & biological engineering & computing》2005,43(1):56-62
Vascular access for renal dialysis is a lifeline for about 120 000 individuals in the United States. Stethoscope auscultation
of vascular sounds has some utility in the assessment of access patency, yet can be highly skill-dependent. The objective
of the study was to identify acoustic parameters that are related to changes in vascular access patency. The underlying hypothesis
is that stenoses of haemodialysis access vessels or grafts cause vascular sound changes that are detectable using computerised
data acquisition and analysis. Eleven patients participated in the study. Their vascular sounds were recorded before and after
angiography, which was accompanied by angioplasty in most patients. The sounds were acquired using two electronic stethoscopes
and then digitised and analysed on a personal computer. Vessel stenosis changes were found to be associated with changes in
acoustic amplitude and/or spectral energy distribution. Certain acoustic parameters correlated well (correlation coefficient=0.98,
p<0.0001) with the change in the degree of stenosis, suggesting that stenosis severity may be predictable from these parameters.
Parameters also appeared to be sensitive to modest diameter changes (>20%), (p<0.005, Wilcoxon rank sum test). These results
suggest that computerised analysis of vascular sounds may be useful in vessel patency surveillance. Further testing using
longitudinal studies may be warranted. 相似文献
999.
Patel T Bansal R Trivedi P Modi L Shah MJ 《Indian journal of pathology & microbiology》2005,48(4):482-484
Metastasis of mesothelioma of the pleura, to the skin and subcutis is an extremely rare occurrence. A 25 year old woman, who had undergone chemotherapy, partial excision of tumor followed by radiotherapy of sarcomatoid mesothelioma of the pleura, presented three months later with painless widespread subcutaneous nodules. FNAC of these nodules reveled pleomorphic malignant spindle shaped cell with epithelioid morphology. The subcutis is a particularly rare site of metastatic sarcomatoid mesothelioma. It is essential to differentiate neoplasm metastatic to the skin and subcutis from primary and benign lesions of the same region. FNAC is accurate and efficient, in conjugation with clinical history, and it also prevents surgical biopsy in the diagnosis of metastatic subcutaneous lesion. To our knowledge, this is the first case, reported till date, in which the sarcomatoid mesothelioma metastasized to the subcutaneous tissue and was diagnosed by fine needle aspiration cytology (FNAC). 相似文献
1000.
Piyush Patel George Philip William Yang Robert Call Friedrich Horak Craig LaForce Leen Gilles Graigory C Garrett S Balachandra Dass Barbara A Knorr Theodore F Reiss 《Annals of allergy, asthma & immunology》2005,95(6):551-557
BACKGROUND: Perennial allergic rhinitis (PAR) is a persistent allergic inflammation of the upper respiratory tract due to year-round allergen exposure. OBJECTIVE: To evaluate the leukotriene receptor antagonist montelukast for the treatment of PAR. METHODS: Protocol 265 was a 2-arm study performed during the winter. After a placebo run-in period, adults with perennial allergen sensitivity and active symptoms of PAR were randomized to receive 10 mg of montelukast (n=1002) or placebo (n=990) once daily during a 6-week, double-blind, active-treatment period. The primary end point was the daytime nasal symptoms score, defined as the average of scores for nasal congestion, rhinorrhea, and sneezing rated daily by patients. RESULTS: Statistically significant improvements in PAR symptoms were seen in patients treated with montelukast. Their daytime nasal symptoms scores were reduced during treatment compared with those of the placebo group: the difference between treatments in least squares mean change from baseline was -0.08 (95% confidence interval [CI], -0.12 to -0.04; P < .001). Montelukast treatment also improved global evaluations of allergic rhinitis by patients and Rhinoconjunctivitis Quality of Life Questionnaire scores: differences vs the placebo group were -0.15 (95% CI, -0.27 to -0.04; P < .01) and -0.15 (95% CI, -0.24 to -0.06; P < .001), respectively. Other end points that showed statistically significant improvement with montelukast treatment were nighttime symptoms and each of the 4 nasal symptoms (congestion, rhinorrhea, sneezing, and itching). The treatment effects of montelukast were stable and persistent during the entire 6 weeks of treatment. CONCLUSION: Montelukast provided statistically significant relief of PAR symptoms during 6 weeks of treatment. 相似文献