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101.
BACKGROUND: With invasion of bacteria, the host defense system is activated by a complex cascade of various mechanisms. Local anesthetics previously were shown to interact with diverse components of the immune response, such as leukocyte adherence on endothelial monolayers, oxidative burst, or crosstalk within lymphocyte subset populations. However, effects of newer local anesthetics like bupivacaine and ropivacaine on antibacterial host defense-primarily phagocytosis activity, oxidative burst, or CD11b expression-still remain unclear. METHODS: Whole blood samples were preincubated with local anesthetics (lidocaine, 9.2, 92.2, and 1,846 microm bupivacaine, 6.1, 61, and 770 microm; ropivacaine, 6.4, 64, and 801 microm). For the oxidative burst and CD11b assay, dihydroethidium was added to the probes. After viable Staphylococcus aureus was added in a 5 to 1 ratio following leukocyte count, phagocytosis was stopped at different times, and staining with monoclonal antibodies was performed for subsequent flow cytometric analysis of phagocytosis activity, oxidative burst, and CD11b expression. RESULTS:Granulocyte phagocytosis activity, CD11b expression, and generation of reactive oxygen species were significantly reduced by lidocaine (P < 0.0002) and bupivacaine (P < 0.005) in the highest concentration (1,846 microm and 770 microm, respectively). The capability of granulocytes to ingest bacteria was significantly depressed only by lidocaine (P < 0.003). Ropivacaine had no significant effect on any parameter investigated. CONCLUSIONS: Local anesthetic dose and structure dependently inhibit inflammatory and immunologic parameters of granulocyte functions. Ropivacaine shows low interference with granulocyte immunologic and inflammatory functions.  相似文献   
102.
103.
Laser scanning confocal fluorescence microscopy: an overview   总被引:2,自引:0,他引:2  
Innovative and important aspects of laser scanning confocal fluorescence imaging (LSCFI) are presented here as a general overview. We have described and discussed the technology of the procedure in some detail. We also report some of our original work with transmembranous uptake of 5S gamma-globulin on living human leukocytes as an example of one specific application of LSCFI. These original data and results are presented, as well as citing other uses and applications, to show the power of LSCFI technique. The article will hopefully be useful for those not familiar with the methodology and utility of laser scanning confocal fluorescence microscopy. Applications of LSCFI are very diverse, and there are new applications of this technology constantly being developed. Interest is growing in LSCFI, particularly in the pharmacologic and therapeutic areas, as demonstrated in this article.  相似文献   
104.
The insulin-like growth factors (IGFs)-1 and -2 have been associated with an increased risk for breast cancer, and have been shown to increase tumor growth and malignant behavior in vitro and in vivo. Both exert their actions through the IGF type 1 receptor (IGF1R), which is able to cooperate with the estrogen receptor in the regulation of growth-associated gene expression. The inhibition of IGF1R signaling, either through receptor blocking or through a reduction of bioactive ligands thus appears to be a highly desirable goal in the suppression of tumor growth. This paper presents a number of compounds that have been shown to reduce IGF serum levels and that might therefore have a potential in controlling tumor growth and possibly metastatic behavior. Some of these are believed to work through a reduction of systemic estrogens, such as anti-estrogens, selective estrogen receptor mediators and aromatase inhibitors, others represent synthetic compounds that belong to the vitamin A and D family.  相似文献   
105.
Energy balance is the difference between energy consumed and total energy expended. Over a given period of time it expresses how much the body stores of fat, carbohydrate and protein will change. For the critically-ill patient, who characteristically exhibits raised energy expenditure and proteolysis of skeletal muscle, energy balance information is valuable because underfeeding or overfeeding may compromise recovery. However, there are formidable difficulties in measuring energy balance in these patients. While energy intake can be accurately recorded in the intensive care setting, the measurement of total energy expenditure is problematic. Widely used approaches, such as direct calorimetry or doubly-labelled water, are not applicable to the critically ill patient. Energy balance was determined over periods of 5-10 d in patients in intensive care by measuring changes in the fat, protein and carbohydrate stores of the body. Changes in total body fat were positively correlated with energy balance over the 5 d study periods in patients with severe sepsis (n 24, r 0.56, P = 0.004) or major trauma (n 24, r 0.70, P < 0.0001). Fat oxidation occurred in patients whose energy intake was insufficient to achieve energy balance. Changes in body protein were independent of energy balance. These results are consistent with those of other researchers who have estimated total energy requirements from measurements of O2 consumption and CO2 production. In critically-ill patients achievement of positive non-protein energy balance or total energy balance does not prevent negative N balance. Nutritional therapy for these patients may in the future focus on glycaemic control with insulin and specialised supplements rather than on energy balance per se.  相似文献   
106.
BACKGROUND: Mycophenolate mofetil (MMF)-based immunosuppression has reduced the acute rejection rate in adults and in children in the early posttransplantation period. Three-year posttransplantation results have been reported for adults but not for children thus far. In the present open-labeled study, patients 18 years old and younger were evaluated prospectively for up to 3 years after renal transplantation (RTX). METHODS: Eighty-six patients receiving MMF in combination with cyclosporine and prednisone without induction were evaluated for patient survival, transplant survival, renal function, arterial blood pressure, adverse events, and opportunistic infections. These patients were compared with a historic control group (n=54) receiving azathioprine (AZA) instead of MMF. RESULTS: Patient survival after 3 years was 98.8% in the MMF group and 94.4% in the AZA group (NS). Intent-to-treat analysis of graft survival demonstrated superiority for MMF (98% vs. 80%; P<0.001). Cumulative acute rejection episodes occurred in 47% of patients in the MMF group versus 61% in the AZA group (P<0.05). Renal function was not significantly different, neither after 3 years nor in the long-term calculation. Antihypertensive medication was administered to 73% to 84% of patients, similar in both groups. Opportunistic infections were recorded only for MMF. Infection rates were comparable to those reported in adults. CONCLUSIONS: These results suggest that MMF is safe and beneficial as a longer term maintenance immunosuppressive drug in children and adolescents.  相似文献   
107.
108.
Diabetic patients undergoing hemodialysis demonstrate much worse survival rates than do nondiabetic patients undergoing hemodialysis. To search for risk predictors, a prospective cohort study was performed with 245 hemodialysis patients, including 84 with diabetes mellitus, for 2 yr. C-reactive protein, troponin T (TnT), total, HDL, LDL, and lipoprotein(a) cholesterol, apoA2, apoB, triglyceride, fibrinogen, D-dimer, albumin, and creatinine levels and clinical characteristics at the time of entry were recorded. Survival rates were compared with Kaplan-Meier and Cox regression analyses. Forty-three diabetic patients and 30 nondiabetic patients died. Among diabetic patients, oliguria (<200 ml/d) (relative risk, 3.24; 95% confidence interval, 1.63 to 6.41; P = 0.001), elevated C-reactive protein levels (relative risk, 2.57; 95% confidence interval, 1.06 to 6.18; P = 0.035), and elevated D-dimer levels (relative risk, 2.36; 95% confidence interval, 1.11 to 5.01; P = 0.025) predicted all-cause mortality rates. Oliguria was by far the most important predictor, particularly for infectious disease-related death (relative risk, 23.35; 95% confidence interval, 2.60 to 209.97; P = 0.005). Among nondiabetic patients, elevated TnT levels (relative risk, 4.00; 95% confidence interval, 1.58 to 10.10; P = 0.003), elevated D-dimer levels (relative risk, 3.45; 95% confidence interval, 1.27 to 9.33; P = 0.015), and low cholesterol levels (relative risk, 3.61; 95% confidence interval, 1.34 to 9.71; P = 0.011) predicted all-cause mortality rates. Subdivision of the causes of death among nondiabetic patients revealed that TnT levels predicted cardiovascular mortality rates (relative risk, 5.38; 95% confidence interval, 1.11 to 26.10; P = 0.037) and infectious disease-related mortality rates (relative risk, 12.02; 95% confidence interval, 1.42 to 191.96; P = 0.023). In conclusion, mortality predictors among patients undergoing hemodialysis differed substantially between diabetic and nondiabetic patients. Strategies to reduce mortality rates should consider these differences.  相似文献   
109.
This paper reports on workplace violence, self-reported as part of a survey among members of the Queensland Nurses' Union (QNU) in October 2001. The aim of the overall study was to ascertain how nurses perceived their work and their working conditions and to use the results of the study to inform strategic planning of the QNU. The participants of this study were drawn from a stratified random sample of 2800 QNU members employed in the public, the private acute and the aged care sectors. The total number of completed surveys analysed was 1436: 441 aged care, 497 public and 498 private acute sector surveys. The results suggest that the rate of workplace violence differs significantly across sectors. In the three months immediately prior to the survey, 50% of aged care sector nurses experienced some form of workplace violence compared to 47% of public sector nurses and 29% of acute private sector nurses. The major source of workplace violence was from patients. The second most common source of violence varied. Nurses in the public sector signified visitors and relatives while nurses in the aged care and acute private sectors indicated other nurses. The study found that inexperienced nurses are more likely to report workplace violence than experienced nurses. Additionally, the more experienced the nurse, the less likely they are to perceive workplace policies and procedures for workplace violence as effective. Additional findings include an apparent lack of policies and procedures for workplace violence in rural and remote areas, and an association between the designation of a nurse and the reported level of workplace violence.  相似文献   
110.
A 20-year-old woman presented with nasal obstruction and slight epistaxis. The obstructing lesion was excised and microscopy showed a neoplasm composed of comparatively uniform undifferentiated cells forming solid nests. The cytoplasm of the cells was clear but poorly demarcated, partly vacuolated and contained much glycogen. Although widespread in the nasal mucosa, the cells did not penetrate into the underlying bone. The cells expressed the MIC2 gene (using the CD99 marker). Electron microscopy showed simple cells with a small number of mitochondria, many glycogen particles; there were no neurosecretory granules present. Early surgical treatment followed by chemo- and radiotherapy have greatly improved the prognosis of EWS: extraskeletal Ewing's sarcoma (EWS/PNET).  相似文献   
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