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901.
Nilesh Lodhia Michael Kader Thalia Mayes Parvez Mantry Benedict Maliakkal 《World journal of gastroenterology : WJG》2009,15(12):1459-1464
AIM: TO evaluate the incidence of contrast-induced nephropathy (CIN) in cirrhotic patients and to identify risk factors for the development of CIN.
METHODS: We performed a retrospective review of 216 consecutive patients with cirrhosis who underwent computed tomography (CT) with intravenous contrast at the University of Rochester between the years 2000-2005. We retrospectively examined factors associated with a high risk for CIN, defined as a decrease in creatinine clearance of 25% or greater within one week after receiving contrast.
RESULTS: Twenty-five percent of our patients developed CIN, and 74% of these patients had ascites seen on CT. Of the 75% of patients who did not develop CIN, only 46% had ascites. The presence of ascites was a significant risk factor for the development of CIN (P = 0.0009, OR 3.38, 95% CI 1.55-7.34) in multivariate analysis. Patient age, serum sodium, Model for End-stage Liver Disease score, diuretic use, and the presence of diabetes were not found to be significant risk factors for the development of CIN. Of the patients who developed CIN, 11% developed chronic renal insufficiency, defined as a creatinine clearance less than baseline for 6 wk.
CONCLUSION: Our results suggest that in hospitalized cirrhotic patients, especially those with ascites, the risk of CIN is substantial. 相似文献
METHODS: We performed a retrospective review of 216 consecutive patients with cirrhosis who underwent computed tomography (CT) with intravenous contrast at the University of Rochester between the years 2000-2005. We retrospectively examined factors associated with a high risk for CIN, defined as a decrease in creatinine clearance of 25% or greater within one week after receiving contrast.
RESULTS: Twenty-five percent of our patients developed CIN, and 74% of these patients had ascites seen on CT. Of the 75% of patients who did not develop CIN, only 46% had ascites. The presence of ascites was a significant risk factor for the development of CIN (P = 0.0009, OR 3.38, 95% CI 1.55-7.34) in multivariate analysis. Patient age, serum sodium, Model for End-stage Liver Disease score, diuretic use, and the presence of diabetes were not found to be significant risk factors for the development of CIN. Of the patients who developed CIN, 11% developed chronic renal insufficiency, defined as a creatinine clearance less than baseline for 6 wk.
CONCLUSION: Our results suggest that in hospitalized cirrhotic patients, especially those with ascites, the risk of CIN is substantial. 相似文献
902.
Zhou J Zhang XQ Ashoori F McConkey DJ Knowles MA Dong L Benedict WF 《Cancer gene therapy》2009,16(1):13-19
RB94, which lacks the N-terminal 112 amino-acid residues of the full-length retinoblastoma protein (RB110) is a more potent inhibitor of cancer cell growth than RB110, being cytotoxic to all cancer cell lines studied, independent of their genetic abnormalities. Although we initially thought RB94-induced cell death was caspase-dependent, such caspase activation now appears to be a late event. Cells that remained attached 48 h after transduction with Ad-RB94 showed, among other changes, nuclear enlargement, peripheral nuclear chromatin condensation and often micronucleation. In addition, the cells were TdT-mediated dUTP nick end labeling (TUNEL) positive but showed no cleavage of caspase 3 or 9. Only after the cells detached was cleavage of both caspase 3 and 9 observed. These TUNEL-positive cells showed neither cytochrome c mitochondrial translocation usually found in typical apoptotic cells nor DNA laddering indicative of oligonucleosomal DNA fragmentation. In addition, although 50 kb DNA fragmentation was produced in these TUNEL-positive cells, which was dependent on apoptosis-inducing factor (AIF), inhibiting this fragmentation by siAIF did not inhibit TUNEL formation or cytotoxicity. As RB94 will soon be used for gene therapy further understanding the molecular basis of these early changes in killing cancer cells is one of our particularly important present goals. 相似文献
903.
Glover P 《Australian College of Midwives Incorporated journal》1999,12(3):12-17
The introduction of the Australian College of Midwives Inc (ACMI) Competency Standards for Midwives in late 1998, has implications for every midwife in Australia. This paper will provide a brief history of the development of nursing and midwifery competencies in Australia, examine what the competencies mean for practice and suggest ways that the competencies can be used for assessment. It is well to remember that the competencies must be considered in context and midwifery legislation and education form a triad for the implementation and use of the competencies. 相似文献
904.
Previous case reports have suggested a strong concordance of intestinal malrotation among identical twins. This has led to
the recommendation that the asymptomatic twin undergo screening when malrotation is discovered in the identical sibling. We
present a case of monozygotic twins in which one twin presented with intestinal malrotation with midgut volvulus while the
other twin was found to have normal gastrointestinal anatomy. 相似文献
905.
BACKGROUND: Extremely preterm birth, even in the absence of significant neurological impairment, is associated with altered pain responses and impaired memory and behaviour. Preterm birth increases the risk of maternal depression and may impede the development of the mother-infant relationship, factors that in turn are also associated with impaired infant outcome. Mother-infant skin-to-skin contact has been recommended as a simple means of ameliorating these effects. METHODS: We conducted a pragmatic, prospective, controlled, intention-to-treat trial in two neonatal intensive care units. Infants born below 32 weeks gestation were recruited within the first week after birth and assigned to a control group receiving standard care, or an intervention group in which mothers were encouraged to provide a session of skin-to-skin contact once daily for 4 weeks. We assessed infant behaviour at time of discharge from hospital, responses to immunisation at 4 and 12 months of age, and memory, behaviour and development at 1 year corrected (postmenstrual) age. Indices of maternal depression, stress, anxiety, lactation performance and infant interaction were assessed at time of infant discharge, 4 months and 1 year. RESULTS: No significant difference was identified in any infant or maternal measure at any time point. CONCLUSIONS: Mother-infant skin-to-skin contact after extremely preterm birth results in neither benefit nor adverse consequences. Although there is no reason to dissuade mothers who wish to provide STS contact, we are unable to recommend resource allocation for the implementation of STS programmes for extremely preterm infants in a neonatal intensive care unit setting. 相似文献
906.
EEG data acquired in an MRI scanner are heavily contaminated by gradient artifacts that can significantly compromise signal quality. We developed two new methods based on independent component analysis (ICA) for reducing gradient artifacts from spiral in–out and echo-planar pulse sequences at 3 T, and compared our algorithms with four other commonly used methods: average artifact subtraction (Allen, P., Josephs, O., Turner, R., 2000. A method for removing imaging artifact from continuous EEG recorded during functional MRI. NeuroImage 12, 230–239.), principal component analysis (Niazy, R., Beckmann, C., Iannetti, G., Brady, J., Smith, S., 2005. Removal of FMRI environment artifacts from EEG data using optimal basis sets. NeuroImage 28, 720–737.), Taylor series ( Wan, X., Iwata, K., Riera, J., Kitamura, M., Kawashima, R., 2006. Artifact reduction for simultaneous EEG/fMRI recording: adaptive FIR reduction of imaging artifacts. Clin. Neurophysiol. 117, 681–692.) and a conventional temporal ICA algorithm. Models of gradient artifacts were derived from simulations as well as a water phantom and performance of each method was evaluated on datasets constructed using visual event-related potentials (ERPs) as well as resting EEG. Our new methods recovered ERPs and resting EEG below the beta band (< 12.5 Hz) with high signal-to-noise ratio (SNR > 4). Our algorithms outperformed all of these methods on resting EEG in the theta and alpha bands (SNR > 4); however, for all methods, signal recovery was modest (SNR 1) in the beta band and poor (SNR < 0.3) in the gamma band and above. We found that the conventional ICA algorithm performed poorly with uniformly low SNR (< 0.1). Taken together, our new ICA-based methods offer a more robust technique for gradient artifact reduction when scanning at 3 T using spiral in–out and echo-planar pulse sequences. We provide new insights into the strengths and weaknesses of each method using a unified subspace framework. 相似文献
907.
It has previously been shown that low-frequency fluctuations in both respiratory volume and cardiac rate can induce changes in the blood-oxygen level dependent (BOLD) signal. Such physiological noise can obscure the detection of neural activation using fMRI, and it is therefore important to model and remove the effects of this noise. While a hemodynamic response function relating respiratory variation (RV) and the BOLD signal has been described [Birn, R.M., Smith, M.A., Jones, T.B., Bandettini, P.A., 2008b. The respiration response function: The temporal dynamics of fMRI signal fluctuations related to changes in respiration. Neuroimage 40, 644-654.], no such mapping for heart rate (HR) has been proposed. In the current study, the effects of RV and HR are simultaneously deconvolved from resting state fMRI. It is demonstrated that a convolution model including RV and HR can explain significantly more variance in gray matter BOLD signal than a model that includes RV alone, and an average HR response function is proposed that well characterizes our subject population. It is observed that the voxel-wise morphology of the deconvolved RV responses is preserved when HR is included in the model, and that its form is adequately modeled by Birn et al.'s previously-described respiration response function. Furthermore, it is shown that modeling out RV and HR can significantly alter functional connectivity maps of the default-mode network. 相似文献
908.
Benedict C Creagh-Brown Mark JD Griffiths Timothy W Evans 《Critical care (London, England)》2009,13(3):221-8
Nitric oxide (NO) is an endogenous mediator of vascular tone and host defence. Inhaled nitric oxide (iNO) results in preferential pulmonary vasodilatation and lowers pulmonary vascular resistance. The route of administration delivers NO selectively to ventilated lung units so that its effect augments that of hypoxic pulmonary vasoconstriction and improves oxygenation. This 'Bench-to-bedside' review focuses on the mechanisms of action of iNO and its clinical applications, with emphasis on acute lung injury and the acute respiratory distress syndrome. Developments in our understanding of the cellular and molecular actions of NO may help to explain the hitherto disappointing results of randomised controlled trials of iNO. 相似文献
909.
Sphenoid sinus fungal balls 总被引:1,自引:0,他引:1
OBJECTIVES: We sought to examine the nature of fungal balls of the sphenoid sinus, in particular the exposure of adjacent skull base structures and the potential for surgical morbidity. METHODS: We retrospectively reviewed our series of 17 cases of sphenoid sinus fungal balls seen between 1998 and 2005 with reference to their diagnosis, radiologic changes, histopathology, and surgical management. RESULTS: Exposed structures included the pituitary fossa, cavernous sinus, and cavernous internal carotid artery, but this exposure did not result in an increase in perioperative complications. Sclerotic thickening of the sinus walls persisted, probably representing a chronic osteitis in response to concurrent bacterial infection. This appeared to be protective against further sinus wall erosions. Wall erosions did not heal. One patient demonstrated what appeared to be invasive fungal disease from a fungal ball. CONCLUSIONS: Sphenoid sinus fungal balls can occur with minimal symptoms in a mainly elderly population and require surgical removal. Sphenoid sinus fungal balls have a low rate of operative morbidity and should be effectively managed by transnasal endoscopic sphenoidotomy alone. 相似文献
910.