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91.
92.
These guidelines have been developed for practitioners who insert catheters and for persons responsible for surveillance and control of infections in hospital, outpatient, and home health-care settings. This report was prepared by a working group comprising members from professional organizations representing the disciplines of critical care medicine, infectious diseases, health-care infection control, surgery anesthesiology interventional radiology pulmonary medicine, pediatric medicine, and nursing. The working group was led by the Society of Critical Care Medicine (SCCM), in collaboration with the Infectious Disease Society of America (IDSA), Society for Healthcare Epidemiology ofAmerica (SHEA), Surgical Infection Society (SIS), American College of Chest Physicians (ACCP), American Thoracic Society (ATS), American Society of Critical Care Anesthesiologists (ASCCA), Association for Professionals in Infection Control and Epidemiology (APIC), Infusion Nurses Society (INS), Oncology Nursing Society (ONS), Society of Cardiovascular and Interventional Radiology (SCVIR), American Academy of Pediatrics (AAP), and the Healthcare Infection Control Practices Advisory Committee (HICPAC) of the Centers for Disease Control and Prevention (CDC) and is intended to replace the Guideline for Prevention of Intravascular Device-Related Infections published in 1996 These guidelines are intended to provide evidence-based recommendations for preventing catheter-related infections. Major areas of emphasis include 1) educating and training health-care providers who insert and maintain catheters; 2) using maximal sterile barrier precautions during central venous catheter insertion; 3) using a 2% chlorhexidine preparation for skin antisepsis; 4) avoiding routine replacement of central venous catheters as a strategy to prevent infection; and 5) using antiseptic/antibiotic impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (i.e., education and training, maximal sterile barrier precautions, and 2% chlorhexidine for skin antisepsis). These guidelines also identify performance indicators that can be used locally by health-care institutions or organizations to monitor their success in implementing these evidence-based recommendations.  相似文献   
93.
We present correlations of extent of temporal lobectomy for intractable epilepsy with postoperative memory changes (20 cases) and abnormalities of visual field and neurologic examination (45 cases). Postoperative magnetic resonance imaging (MRI) in the coronal plane was used to quantify anteroposterior extent of resection of various quadrants of the temporal lobe, using a 20-compartment model of that structure. The Wechsler Memory Scale-Revised (WMS-R) was administered preoperatively and postoperatively. Postoperative decrease in percentage of retention of verbal material correlated with extent of medial resection of left temporal lobe, whereas decrease in percentage of retention of visual material correlated with extent of medial resection of right temporal lobe. These correlations approached but did not reach statistical significance. Extent of resection correlated significantly with the presence of visual field defect on perimetry testing but not with severity, denseness, or congruity of the defect. There was no correlation between postoperative dysphasia and extent of resection in any quadrant. Assessment of extent of resection after temporal lobectomy allows a rational interpretation of postoperative neurologic deficits in light of functional anatomy of the temporal lobe.  相似文献   
94.
Complete ureteric occlusion produces various pathophysiological changes that can be monitored externally by technetium 99m diethylenetriamine penta-acetic acid (99mTc-DTPA) diuretic renography (RDR). Being a dynamic imaging study, it reflects the function of the kidneys and the urodynamics of the urinary tract. The aim of this study was to correlate the changes in parameters of RDR with the histological changes before and after the release of complete ureteric occlusion. In 9 sheep, RDR studies were performed serially after various periods of complete ureteric occlusion (up to 7 weeks) and after release of the occlusion (up to 5 weeks). The histological changes were correlated with changes in RDR. The progressive decrease in renal flow seen on renal images and flow time-activity curves (TACs) was explained by the development of endarteritis and thrombosis of small renal arteries. The progressive decrease in the renal uptake as indicated by the percentage renal uptake and the extraction slope of TAC is related to the progressive damage to the renal parenchyma, initially affecting the collecting ducts and tubules, with increasing interstitial fibrosis in the later stages. Obstruction for 3 weeks or less was associated with moderate damage to the parenchyma from which recovery was possible. Obstruction for 7 weeks was associated with marked damage without chance of recovery. The RDR is a non-invasive technique that can be used to monitor kidney damage after various periods of complete ureteric occlusion and to predict the outcome of surgery before the release of occlusion.This project was supported by grant no. MN013 from the Research Council, Kuwait University  相似文献   
95.
The extent of resection was assessed in 45 temporal lobectomies for medically intractable epilepsy with mapped temporal lobe foci. Postoperative magnetic resonance imaging (MRI) in the coronal plane was used to quantify the extent of resection of superior lateral, inferior lateral, basal, and medial structures, including the amygdalohippocampal complex. A new 20-compartment model of the temporal lobe was used for this assessment. Blinded interobserver variability was minimal. Intraoperative measurements and maps routinely overestimated the actual extent of resection, especially of medial structures. One year after surgery, 70% of patients remained seizure-free (except for auras). Seizure-free outcome was accomplished despite varying degrees of resection, but was more likely achieved with more extensive resections in all compartments. Among patients with mesiobasal foci, seizure-free outcome correlated significantly with extent of resection of amygdalohippocampal complex. We conclude that assessment of extent of resection by postoperative MRI provides an objective basis of evaluating outcome after temporal lobectomy. It allows a rational approach to understanding of operative failures and is potentially useful in comparing efficacy of various surgical approaches.  相似文献   
96.
PURPOSE: To determine the clinical, dosimetric, and spatial parameters that correlate with radiation pneumonitis. METHODS AND MATERIALS: Patients treated with high-dose radiation for non-small-cell lung cancer with three-dimensional treatment planning were reviewed for clinical information and radiation pneumonitis (RP) events. Three-dimensional treatment plans for 219 eligible patients were recovered. Treatment plan information, including parameters defining tumor position and dose-volume parameters, was extracted from non-heterogeneity-corrected dose distributions. Correlation to RP events was assessed by Spearman's rank correlation coefficient (R). Mathematical models were generated that correlate with RP. RESULTS: Of 219 patients, 52 required treatment for RP (median interval, 142 days). Tumor location was the most highly correlated parameter on univariate analysis (R = 0.24). Multiple dose-volume parameters were correlated with RP. Models most frequently selected by bootstrap resampling included tumor position, maximum dose, and D35 (minimum dose to the 35% volume receiving the highest doses) (R = 0.28). The most frequently selected two- or three-parameter models outperformed commonly used metrics, including V20 (fractional volume of normal lung receiving >20 Gy) and mean lung dose (R = 0.18). CONCLUSIONS: Inferior tumor position was highly correlated with pneumonitis events within our population. Models that account for inferior tumor position and dosimetric information, including both high- and low-dose regions (D(35), International Commission on Radiation Units and Measurements maximum dose), risk-stratify patients more accurately than any single dosimetric or clinical parameter.  相似文献   
97.
PURPOSE: The probability of a specific radiotherapy outcome is typically a complex, unknown function of dosimetric and clinical factors. Current models are usually oversimplified. We describe alternative methods for building multivariable dose-response models. METHODS: Representative data sets of esophagitis and xerostomia are used. We use a logistic regression framework to approximate the treatment-response function. Bootstrap replications are performed to explore variable selection stability. To guard against under/overfitting, we compare several analytical and data-driven methods for model-order estimation. Spearman's coefficient is used to evaluate performance robustness. Novel graphical displays of variable cross correlations and bootstrap selection are demonstrated. RESULTS: Bootstrap variable selection techniques improve model building by reducing sample size effects and unveiling variable cross correlations. Inference by resampling and Bayesian approaches produced generally consistent guidance for model order estimation. The optimal esophagitis model consisted of 5 dosimetric/clinical variables. Although the xerostomia model could be improved by combining clinical and dose-volume factors, the improvement would be small. CONCLUSIONS: Prediction of treatment response can be improved by mixing clinical and dose-volume factors. Graphical tools can mitigate the inherent complexity of multivariable modeling. Bootstrap-based variable selection analysis increases the reliability of reported models. Statistical inference methods combined with Spearman's coefficient provide an efficient approach to estimating optimal model order.  相似文献   
98.
STUDY OBJECTIVES: To determine the frequency and type of complementary and alternative medicine (CAM) use among healthy volunteers participating in research, and to investigate the potential for interactions between commonly used CAM modalities and various drugs. DESIGN: Prospective evaluation. SETTING: University general clinical research center. SUBJECTS: Sixty healthy adults participating in an ongoing drug study. MEASUREMENTS AND MAIN RESULTS: The clinical study database was queried to determine the use and type of existing and newly started CAM throughout the study period. Baseline characteristics were compared between users and nonusers of CAM to identify differences between them. Potential CAM-drug interactions were classified based on curated databases and primary literature sources. Of the 60 subjects enrolled, 30 (50%) used CAM during the study. Of these, 26 (87%) were using CAM at study entry. Baseline CAM users were on average 7 years older than nonusers (p=0.03) and had high-density lipoprotein cholesterol concentrations 10 mg/dl higher than those of nonusers (p=0.04). The group using CAM had more women and nonsmokers than the other group. Several potential CAM-drug interactions were identified. CONCLUSION: Because of high rates of CAM use (50% of the subjects were using biologically based CAM) and the many potential CAM-drug interactions, CAM use should be rigorously addressed in clinical practice and research. Failure to capture this information may have clinical repercussions through pharmacokinetic and pharmacodynamic interference of clinical response and clinical trial results. Clinicians and researchers may be able to identify those most likely to use CAM by their baseline characteristics; this would help target those patients and research subjects for more thorough assessment and follow-up.  相似文献   
99.
STUDY OBJECTIVES: To investigate whether atorvastatin decreases serum or leukocyte-produced CD40 ligand (CD40L) levels and whether these effects are dependent on reduction in low-density lipoprotein cholesterol (LDL) levels in people without overt dyslipidemia. DESIGN: Prospective pilot study. SETTING: University research center. SUBJECTS: Twenty-five normocholesterolemic volunteers (mean age 32 +/- 11 yrs; 15 women, 10 men) without cardiovascular disease. INTERVENTION: After a 2-week drug-free run-in period, subjects received atorvastatin 80 mg/day orally for 16 weeks. MEASUREMENTS AND MAIN RESULTS: All lipoprotein level measurements were performed with the subject in the fasting state. The CD40L concentrations were measured by immunofluorescence detection in serum and leukocyte culture supernates after 24-hour incubation, and treatment effect was analyzed. Baseline mean +/- SD total cholesterol, LDL, high-density lipoprotein cholesterol, and triglyceride levels were 179 +/- 33, 97 +/- 29, 62 +/- 20, and 102 +/- 69 mg/dl, respectively. Mean changes in each of these levels, respectively, after 16 weeks of atorvastatin were -34%, -59%, +3%, and -23%. The median serum CD40L level was lower at 16 weeks (2.3 ng/ml, interquartile range [IQR] 1.2-5.0 ng/ml) than at baseline (3.0 ng/ml, IQR 2.1-3.7 ng/ml), but the change was not significant (p=0.24). However, atorvastatin significantly lowered CD40L produced from leukocytes by 57% (21 pg/mg of protein [IQR 10-38 pg/mg] vs 49 pg/mg [IQR 21-149 pg/mg], p=0.045). Effects were independent of reduction in cholesterol levels. CONCLUSION: Although atorvastatin did not significantly lower serum CD40L levels, significant reduction in leukocyte production was seen independent of degree of LDL reduction. These pilot data suggest a potential benefit in normocholesterolemic individuals that should be further investigated, and that leukocyte CD40L concentrations should be considered in the drug response.  相似文献   
100.
Since the start of the second Palestinian uprising (Al-Aqsa Intifada), and due to the Israeli activities, curfews, closures, and military checkpoints imposed since 2000, the quality of social services rendered by Nablus city has been gradually deteriorating. Solid waste management in Nablus city was badly affected by these conditions, and this situation is negatively affecting health and damaging the environment. Most of these cases were due to reasons beyond the capability of the municipality with its limited resources. This study revealed that some of the important municipal solid waste (MSW) equipment had been damaged during the uprising. The workforce in the MSW system was reduced and certain MSW-related development projects and activities have been frozen due to the current conditions. The city's medical waste incinerator had been phased out and the number of special medical containers had been reduced from 16 to 10. Some MSW compressing trucks had been out of use with no substitute. Another important figure is the number of waste collection workers which decreased from 420 to 301, although the city is growing in premises as well as population. The created unsanitary solid waste transfer station is now a pollution source on its own, causing an ugly scene at the eastern entrance of Nablus city. There should be a comprehensive and urgent solution for this problem and the needed resources should be invested.  相似文献   
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