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991.
To attract nurses to the workforce, scheduling of nurses on patient care units has evolved into a mixture of 4-, 6-, 8-, and 12-hour shifts. The result is chaotic as staff members come and go at varying times, creating the need for multiple handoffs and reassignment of patients. Effective teamwork and continuity of care are difficult, if not impossible, to achieve under these circumstances. The authors describe the effect of using just 1 shift length for all nursing staff. 相似文献
992.
De Luca A Nico B Rolland JF Cozzoli A Burdi R Mangieri D Giannuzzi V Liantonio A Cippone V De Bellis M Nicchia GP Camerino GM Frigeri A Svelto M Camerino DC 《Neurobiology of disease》2008,32(2):243-253
Aminoglycosides force read through of premature stop codon mutations and introduce new mutation-specific gene-corrective strategies in Duchenne muscular dystrophy. A chronic treatment with gentamicin (32 mg/kg/daily i.p., 8-12 weeks) was performed in exercised mdx mice with the dual aim to clarify the dependence on dystrophin of the functional, biochemical and histological alterations present in dystrophic muscle and to verify the long term efficiency of small molecule gene-corrective strategies in work-loaded dystrophic muscle. The treatment counteracted the exercise-induced impairment of in vivo forelimb strength after 6-8 weeks. We observed an increase in dystrophin expression level in all the fibers, although lower than that observed in normal fibers, and found a concomitant recovery of aquaporin-4 at sarcolemma. A significant reduction in centronucleated fibers, in the area of necrosis and in the percentage of nuclear factor-kB-positive nuclei was observed in gastrocnemious muscle of treated animals. Plasma creatine kinase was reduced by 70%. Ex vivo, gentamicin restored membrane ionic conductance in mdx diaphragm and limb muscle fibers. No effects were observed on the altered calcium homeostasis and sarcolemmal calcium permeability, detected by electrophysiological and microspectrofluorimetric approaches. Thus, the maintenance of a partial level of dystrophin is sufficient to reinforce sarcolemmal stability, reducing leakiness, inflammation and fiber damage, while correction of altered calcium homeostasis needs greater expression of dystrophin or direct interventions on the channels involved. 相似文献
993.
994.
Haustein MD Reinert T Warnatsch A Englitz B Dietz B Robitzki A Rübsamen R Milenkovic I 《Journal of neuroscience methods》2008,174(2):227-236
We assessed the potential of using multielectrode arrays (MEAs) to investigate several physiological properties of the calyx of Held synapse in the medial nucleus of the trapezoid body of gerbil. Due to the large size of the synapse, it became widely employed in studies on synaptic mechanisms. Electrical stimulation at the midline evoked a characteristic compound signal consisting of a presynaptic volley (C(1)) and a postsynaptic response (C(2)). The C(1) was blocked by tetrodotoxin, whilst the C(2) was blocked by perfusion of low Ca(2+) external solution, or the AMPA-R antagonists CNQX, and GYKI52466. NMDA-R blocker D-AP5, partially inhibited the postsynaptic response at P12, but showed no effect in P30 animals. The inhibitory effects of GABA or glycine on postsynaptic responses were reciprocal with regard to animal's maturity: GABA caused a pronounced reduction of C(2) amplitude in P20-22 animals, while glycine showed a stronger inhibition in P27-28 animals. Low-frequency super-threshold stimulation of the afferents induced facilitation of the postsynaptic C(2) amplitudes and only minor changes in temporal characteristics of the signals. At stimulation frequencies >200Hz, however, significant depression occurs accompanied by increases in transmission delay and in the width of the postsynaptic response. This study suggests MEAs as a useful tool to study calyx of Held synapse by simultaneous recordings of pre- and postsynaptic elements of synaptically interconnected neurons in the auditory brainstem. Moreover, MEAs enable convenient analysis of activity-dependent depression and modulation of neuronal activity by glycine and GABA at later developmental stages not accessible to patch recordings. 相似文献
995.
Patients with Huntington's disease (HD) exhibit motor impairments as well as cognitive and emotional deficits. So far impairments in the ability to recognize emotional stimuli have mostly been investigated by using facial expressions and emotional voices. Other important emotional signals are provided by the whole body. To investigate the impact of motor deficits on body recognition and the relation between motor disorders and emotion perception deficits, we tested recognition of emotional body language (instrumental, angry, fearful and sad) in 19 HD patients and their matched controls with a nonverbal whole body expression matching task. Results indicate that HD patients are impaired in recognizing both instrumental and angry whole body postures. Furthermore, the body language perception deficits are correlated with measures of motor deficit. Taken together the results suggest a close relationship between emotion recognition (specifically anger) and motor abilities. 相似文献
996.
Spring S Simon R van der Loo B Kovacevic T Brockes C Rousson V Amann-Vesti B Koppensteiner R 《Thrombosis and haemostasis》2008,99(1):182-189
Beneficial effects of aggressive lipid-lowering with high-dose atorvastatin (80 mg/day) have been demonstrated in patients with coronary and cerebrovascular disease. The impact of such a therapy in patients with peripheral arterial disease (PAD) is less known so far. Here we studied the effects of high-dose atorvastatin on brachial artery endothelial function, common carotid intima-media thickness (IMT) and local progression of PAD in these patients. One hundred of 500 patients screened with documented PAD were randomly assigned to receive 80 mg of atorvastatin daily for six months or to continue on conventional medical treatment. Ninety-six percent of patients in the control group were on standard statin treatment. High resolution B-mode ultrasonography was used to study brachial artery flow-mediated dilation (FMD), IMT and ankle-brachial index (ABI) at baseline and at six months. FMD and IMT at baseline and at six months were 4.1 (0.06-8.6) versus 5.0 (0.76 vs. 8.1) %, p = 0.96, and 0.76 (0.66-0.82) versus 0.73 (0.63-0.81) mm, p = 0.41, respectively, in the atorvastatin group, and 2.66 (-1.9-6.9) versus 3.65 (0.0-8.6)%, p = 0.02, and 0.78 (0.71-0.90) versus 0.77 (0.70-0.90) mm, p = 0.48, in the control group. ABI at baseline and at six months was not different in either group. LDL cholesterol was reduced from 2.53 (2.21-3.28) to 1.86 (1.38-2.29) mM (p < 0.0001) in the atorvastatin group, whereas levels remained stable in the control group [2.38 (1.94-3.16) vs. 2.33 (1.82-2.84) mM, p = 0.61]. Major adverse cardiovascular events occurred in 2.1% in the atorvastatin group and 1.9% in the control group (p = 0.61). In conclusion, in this pilot trial aggressive lipid-lowering with 80 mg of atorvastatin daily for six months had no effect on brachial artery FMD in patients with PAD. IMT and ABI were also similar in patients with and without high-dose atorvastatin at six months. 相似文献
997.
Gill RR Gerbaudo VH Jacobson FL Trotman-Dickenson B Matsuoka S Hunsaker A Sugarbaker DJ Hatabu H 《Magnetic Resonance Imaging Clinics of North America》2008,16(2):319-39, x
MR imaging serves as a problem-solving tool in the diagnosis of inflammatory and infectious pleural diseases and primary and secondary pleural malignancies. Knowledge of MR imaging appearance of pleural diseases, including pleural effusions and empyema, benign and malignant pleural tumors, and especially mesothelioma, helps guide treatment decisions and surgical planning. 相似文献
998.
999.
Comparison of 64-slice computed tomography planimetry and Doppler echocardiography in the assessment of aortic valve stenosis 总被引:3,自引:0,他引:3
Habis M Daoud B Roger VL Ghostine S Caussin C Ramadan R Nottin R Lancelin B Angel CY Capderou A Paul JF 《The Journal of heart valve disease》2007,16(3):216-224
BACKGROUND AND AIM of the study: The study aim was to compare, prospectively, the planimetry of aortic stenosis on 64-slice computed tomography (CT), with the area calculated by Doppler transthoracic echocardiography (TTE) in symptomatic patients evaluated before potential aortic valve replacement. METHODS: Fifty-two consecutive patients (27 males, 25 females; mean age 74 +/- 10 years) admitted to the authors' institution during 2005 were evaluated with 64-slice CT and Doppler TTE. The time interval between the two evaluations was 2 +/- 1 weeks. Planimetry of the anatomic orifice area (AOA) drawn on 64-slice CT was compared to the effective area determined by Doppler TTE by Bland and Altman analysis, and the anatomic area threshold value corresponding to a significant effective aortic stenosis (50.75 cm2) was determined by receiver operating characteristic (ROC) analysis. RESULTS: The aortic orifice area measured by 64-slice CT correlated well with the effective area (r = 0.76; p <0.0001), but was significantly greater, with a systematic overestimation (0.132 cm(2)) and a variability of 0.239 cm(2). There was good agreement between planimetry determined by two independent radiologists (difference = 0.002, variability = 0.115 cm(2)). ROC analysis showed that a threshold value of 0.95 cm(2) as measured by 64-slice CT planimetry identifies significant aortic stenosis with sensitivity, specificity, accuracy, positive and negative predictive values of 82%, 77%, 81%, 91% and 59%, respectively. CONCLUSION: 64-slice CT is a reproducible and reliable non-invasive method to evaluate aortic valve stenosis compared to the reference method of Doppler TTE. Indeed, the CT approach could replace the latter evaluation when measurements used in the continuity equation are inadequate. 相似文献
1000.
Tau is a microtubule-associated protein involved in microtubule assembly and stabilization. Filamentous deposits made of tau constitute a major defining characteristic of several neurodegenerative diseases known as tauopathies including Alzheimer's disease. The involvement of tau in neurodegeneration has been clarified by the identification of genetic mutations in the tau gene in cases with familial frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). Although the mechanism through which tau mutations lead to neuronal death is still unresolved, it is clear that tau mutations lead to formation of tau filaments that have a different morphology, contain different types of tau isoforms and produce distinct tau deposits. The range of tau pathology identified in FTDP-17 recapitulates the tau pathology present in sporadic tauopathies and indicates that tau dysfunction plays a major role also in these diseases. 相似文献