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71.
Automation is an open subject in DNA microarray image processing, aiming reliable gene expression estimation. The paper presents a novel shock filter based approach for automatic microarray grid alignment. The proposed method brings up significantly reduced computational complexity compared to state of the art approaches, while similar results in terms of accuracy are achieved. Based on this approach, we also propose an FPGA based system for microarray image analysis that eliminates the shortcomings of existing software platforms: user intervention, increased computational time and cost. Our system includes application-specific architectures which involve algorithm parallelization, aiming fast and automated cDNA microarray image processing. The proposed automated image processing chain is implemented both on a general purpose processor and using the developed hardware architectures as co-processors in a FPGA based system. The comparative results included in the last section show that an important gain in terms of computational time is obtained using hardware based implementations.  相似文献   
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Our study explored the effects of deliberate practice on the retention ofcardiopulmonary resuscitation (CPR) psychomotor skills among nursing students. The practice sessions were short, six minutes a session one time a month. Differences in performance between students who had deliberate practice and a control group, with no practice beyond the initial training, were compared every three months for one year. The intervention group performed better than the control over the 12 months. There is a need in nursing education for deliberate practice of relevant and high-use skills for students to improve their performance and gradually develop their expertise.  相似文献   
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INTRODUCTION: A recent survey of respiratory intensive care units (RICU) in Italy showed that RICUs in Italy are mainly (85%) located in acute care hospitals. Forty-seven percent of the patients are admitted from emergency departments, and only 18% are admitted from intensive care units (ICU), so the percentage of patients admitted for difficulty in weaning is low (8%). Patient demographics and admission patterns in RICUs located outside acute care hospitals have not been previously described. METHODS: We analyzed admission patterns, demographics, treatment, and outcomes of patients during the first year of operation of a 7-bed RICU located in a rehabilitation center that does not have an emergency department. RESULTS: In the 1-year study period, 96 RICU patients were admitted for acute or chronic respiratory failure. The patients' mean Simplified Acute Physiology Score II was 28.9 +/- 3.6. Sixty-five percent of the patients were transferred from the ICU, 17% from medical wards of other hospitals, 7% and 5%, respectively, from the medical and surgical wards of our hospital, and 6% came directly from home for a periodic check. Difficulty in weaning from mechanical ventilation was the main reason for admission (42%), followed by simple monitoring (37%) and need for acute ventilatory invasive or noninvasive support (21%). Thirty-one patients had COPD, 23 had acute hypoxemic respiratory failure, 30 had post-surgical complications, and 12 had neuromuscular disease. Twenty-seven of 40 patients admitted for difficulty in weaning were liberated from ventilation. Intrahospital mortality was 13%. Fifty percent of patients were discharged directly to home; those patients' mean Dependence Nursing Scale score (which measures the degree of patient independence) improved during hospital stay (decreased from 23 to 12 [p < 0.05]), whereas the remaining patients were transferred to long-term facilities or an acute care hospital. CONCLUSIONS: The admission pattern at our RICU in a rehabilitation center is quite different from that of an RICU in an acute care hospital. Most of our patients are admitted from ICU because of difficulty with weaning. This may be the consequence of the institutional philosophy of rehabilitation centers, which strive to achieve greater patient independence.  相似文献   
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Kraft M  Cassell GH  Pak J  Martin RJ 《Chest》2002,121(6):1782-1788
STUDY OBJECTIVES: To determine the effect of clarithromycin therapy in patients with asthma. DESIGN: Randomized, double blind, placebo-controlled trial. SETTING: A tertiary referral center. PATIENTS OR PARTICIPANTS: Fifty-five subjects with chronic, stable asthma recruited from the general Denver, CO, community. INTERVENTIONS: Patients underwent airway evaluation for Mycoplasma pneumoniae and Chlamydia pneumoniae by polymerase chain reaction (PCR) and culture, followed by treatment with clarithromycin, 500 bid, or placebo for 6 weeks. MEASUREMENTS AND RESULTS: Outcome variables were lung function, sinusitis as measured by CT, and the inflammatory mediators tumor necrosis factor (TNF)-alpha, interleukin (IL)-2, IL-4, IL-5, and IL-12 messenger RNA (mRNA) measured via in situ hybridization, in airway biopsies, and BAL. Mycoplasma or chlamydia were detected by PCR in 31 of 55 asthmatics. Treatment resulted in a significant improvement in the FEV(1), but only in the PCR-positive subjects (2.50 +/- 0.16 to 2.69 +/- 0.19 L, mean +/- SEM; p = 0.05). This was not appreciated in the PCR-negative subjects (2.59 +/- 0.24 to 2.54 +/- 0.18 L, p = 0.85) or the PCR-positive or PCR-negative subjects who received placebo. Sinus CTs revealed no change in sinusitis with clarithromycin treatment. In situ hybridization revealed no significant difference in baseline airway tissue or BAL-mediator expression between the PCR-positive and PCR-negative subjects. However, the PCR-positive subjects who received clarithromycin demonstrated a reduction in TNF-alpha (p = 0.006), IL-5 (p = 0.007), and IL-12 (p = 0.004) mRNA in BAL and TNF-alpha mRNA in airway tissue (p = 0.0009). The PCR-negative subjects who received clarithromycin only demonstrated a reduction in TNF-alpha (p = 0.01) and IL-12 (p = 0.002) mRNA in BAL and TNF-alpha mRNA in airway tissue (p = 0.004). There were no significant differences in cytokine expression in those subjects who received placebo. CONCLUSIONS: These observations support the hypothesis that clarithromycin therapy improves lung function, but only in those subjects with positive PCR findings for M pneumoniae or C pneumoniae.  相似文献   
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In the fight against heart failure, therapeutics that have the ability to increase the contractile power of the heart are urgently needed. One possible route of action to improve heart contractile power is increasing the calcium sensitivity of the thin filament. From a pharmaceutical standpoint, calcium sensitizers have the distinct advantage of not altering cardiomyocyte calcium levels and thus have lower potential for side-effects. Small chemical molecules have been shown to bind to the interface between cTnC and the cTnI switch peptide and exhibit calcium-sensitizing properties, possibly by stabilizing cTnC in an open conformation. Building on existing structural data of a known calcium sensitizer bound to cardiac troponin, we combined computational structure-based virtual screening drug discovery methods and solution NMR titration assays to identify a novel calcium sensitizer 4-(4-(2,5-dimethylphenyl)-1-piperazinyl)-3-pyridinamine (NSC147866) which binds to cTnC and the cTnC-cTnI147–163 complex. Its presence increases the affinity of switch peptide to cTnC by approximately a factor of two. This action is comparable to that of known levosimendan analogues.  相似文献   
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