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61.

Background  

Pressure ulcers are a common, painful and costly condition. Results of a 1991 study into the knowledge among Dutch hospital nurses on the usefulness of measures to prevent pressure ulcers showed moderate knowledge. Results were confirmed by subsequent studies. In recent years, Dutch guidelines have been updated and the attention given to pressure ulcer care has been increased. This was expected to improve pressure ulcer care and to increase nurses' knowledge. The aims of the current study were to investigate (1) how much nurses employed in Dutch hospitals know about the usefulness of 28 preventive measures considered in the most recent national pressure ulcer guideline; (2) whether differences in knowledge exist between nurses working in hospitals that audit pressure ulcers and those employed in hospitals that do not; and (3) to study whether knowledge among Dutch hospital nurses regarding the usefulness of preventive measures had changed between 1991 and 2003.  相似文献   
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63.

Background and purpose:

The OX2 receptor is a G-protein-coupled receptor that is abundantly found in the tuberomammillary nucleus, an important site for the regulation of the sleep-wake state. Herein, we describe the in vitro and in vivo properties of a selective OX2 receptor antagonist, N-ethyl-2-[(6-methoxy-pyridin-3-yl)-(toluene-2-sulphonyl)-amino]-N-pyridin-3-ylmethyl-acetamide (EMPA).

Experimental approach:

The affinity of [3H]EMPA was assessed in membranes from HEK293-hOX2-cells using saturation and binding kinetics. The antagonist properties of EMPA were determined by Schild analysis using the orexin-A-or orexin-B-induced accumulation of [3H]inositol phosphates (IP). Quantitative autoradiography was used to determine the distribution and abundance of OX2 receptors in rat brain. The in vivo activity of EMPA was assessed by reversal of [Ala11,D-Leu15]orexin-B-induced hyperlocomotion during the resting phase in mice and the reduction of spontaneous locomotor activity (LMA) during the active phase in rats.

Key results:

[3H]EMPA bound to human and rat OX2-HEK293 membranes with KD values of 1.1 and 1.4 nmol·L−1 respectively. EMPA competitively antagonized orexin-A-and orexin-B-evoked accumulation of [3H]IP at hOX2 receptors with pA2 values of 8.6 and 8.8 respectively. Autoradiography of rat brain confirmed the selectivity of [3H]EMPA for OX2 receptors. EMPA significantly reversed [Ala11,D-Leu15]orexin-B-induced hyperlocomotion dose-dependently during the resting phase in mice. EMPA, injected i.p. in rats during the active phase, reduced LMA dose-dependently. EMPA did not impair performance of rats in the rotarod procedure.

Conclusions and implications:

EMPA is a high-affinity, reversible and selective OX2 receptor antagonist, active in vivo, which should prove useful for analysis of OX2 receptor function.  相似文献   
64.

Background and purpose:

The sarcoplasmic reticulum (SR), regulates the cytoplasmic Ca2+ concentration ([Ca2+]cyto) in vascular smooth muscle. Release from the SR is controlled by two intracellular receptor/channel complexes, the ryanodine receptor (RyR) and the inositol 1,4,5-trisphosphate receptor (IP3R). These receptors may be regulated by the accessory FK506-binding protein (FKBP) either directly, by binding to the channel, or indirectly via FKBP modulation of two targets, the phosphatase, calcineurin or the kinase, mammalian target of rapamycin (mTOR).

Experimental approach:

Single portal vein myocytes were voltage-clamped in whole cell configuration and [Ca2+]cyto measured using fluo-3. IP3Rs were activated by photolysis of caged IP3 and RyRs activated by hydrostatic application of caffeine.

Key results:

FK506 which displaces FKBP from each receptor (to inhibit calcineurin) increased the [Ca2+]cyto rise evoked by activation of either RyR or IP3R. Rapamycin which displaces FKBP (to inhibit mTOR) also increased the amplitude of the caffeine-evoked, but reduced the IP3-evoked [Ca2+]cyto rise. None of the phosphatase inhibitors, cypermethrin, okadaic acid or calcineurin inhibitory peptide, altered either caffeine- or IP3-evoked [Ca2+]cyto release; calcineurin did not contribute to FK506-mediated potentiation of RyR- or IP3R-mediated Ca2+ release. The mTOR inhibitor LY294002, like rapamycin, decreased IP3-evoked Ca2+ release.

Conclusions and implications:

Ca2+ release in portal vein myocytes, via RyR, was modulated directly by FKBP binding to the channel; neither calcineurin nor mTOR contributed to this regulation. However, IP3R-mediated Ca2+ release, while also modulated directly by FKBP may be additionally regulated by mTOR. Rapamycin inhibition of IP3-mediated Ca2+ release may be explained by mTOR inhibition.  相似文献   
65.
Objective To explore the characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Seven patients with arrhythmogenic right ventricular cardiomyopathy and 34 members of three families were studied. All patients and family members underwent history collection, clinical examination, electrocardiogram (ECG), two-dimensional echocardiography (2-DE) and a signal averaging electrocardiogram. Programmed ventricular stimulation was performed in five patients. Results All patients and family members had normal morphologic characteristics and normal function of the left ventricular by 2-DE. Fourteen persons had abnormal findings indicating ARVC. Five had enlargement of the right ventricular with diffused hypocontractility, eight had thin and systolic bulging in the focal anterior wall with hypokinesia and one had bulging of the inferior wall. Twenty-five persons (seven patients and 18 family members) had abnormal findings in ECG. Positive ventricular late potential was recorded in 13 persons (six patients). Two to three monomorphic ventricular tachycardia (VT) with left bundle branch block (LBBB) configurations were induced in five patients. Ventricular fibrillation was induced in two patients during the electrophysiologic study (EPS). Five patients had very high pacing threshold and/or ineffective pacing in one or many regions of the right ventricle. Two members of one family died suddenly. One member was a dwarf with ARVC. Spontaneous VT with a left bundle branch block (LBBB) configuration was recorded in five patients, polymorphic VT with extremely short coupling interval in one, and premature ventricular complexes with LBBB configuration in 12 (six patients). Conclusion Our familial study strongly suggests that ARVC may be a hereditary disease and it is helpful in the diagnosis and detection of ARVC. The most common manifestations were abnormal structure and function of the right ventricle and abnormal ECG of repolarization and ventricular arrhythmia which originates from the right ventricle.  相似文献   
66.
OBJECT: The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS: Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyms. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS: Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance.  相似文献   
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69.
Donor sepsis is not a contraindication to cadaveric organ donation   总被引:1,自引:0,他引:1  
Systemic donor infection is regarded as being an absolute contraindication to cadaveric organ donation for transplantation. This is largely due to fear of transmitting pathogenic organisms to the immunosuppressed recipient. However, due to the current shortage of organs available for transplantation, clinicians are faced with the option of using organs from 'non-ideal' donors, such as those patients with documented evidence of infection. We report the successful outcome of six orthotopic liver transplants, 11 renal transplants, one combined heart lung transplant and one simultaneous kidney and pancreas transplant with organs from eight donors in whom bacterial meningitis (n = 7) and acute bacterial epiglottitis (n = 1) were the antecedent causes of death.   相似文献   
70.
Normal and diseased isolated lungs: high-resolution CT   总被引:8,自引:0,他引:8  
  相似文献   
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