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61.
To determine the relationships between HbA1c, characteristics of hyperglycemia and glycemic variability in well-controlled type 2 diabetes (HbA1c<7.0%), we studied 63 primary-care patients (36 men and 27 women), aged 34-75 years, with type 2 diabetes for 2-32 years using a continuous glucose monitoring system (CGMS) and standardized meal test (MMT). Duration of hyperglycemia (>8.0 mmol/l), standard deviation score (S.D.-score) and mean amplitude of glycemic excursions (MAGE) were analyzed from CGMS data and postprandial glucose during MMT (PPG(MMT)). Patients were hyperglycemic for 5.7h/day (median), experienced 4.1 hyperglycemic episodes/day, and 78% exceeded PPG levels of 8.0 mmol/l. HbA1c, though associated with the extent of hyperglycemia (r=0.40, p<0.001), failed to correlate with S.D.-score and MAGE. Multiple regression analysis demonstrated that HbA1c was predicted only by fasting glucose (R(2)=0.24, p<0.001) but neither by PPG(MMT), duration of hyperglycemia, S.D.-score nor MAGE. CGMS and meal test provide the tools for complete characterization of glycemia in type 2 diabetes. In well-controlled type 2 diabetes, HbA1c correlates with chronic hyperglycemia but not with glucose variability. Our data suggest that chronic sustained hyperglycemia and glucose fluctuations are two independent components of dysglycemia in diabetes.  相似文献   
62.
PURPOSE: To evaluate MRI for a qualitative and quantitative in vivo tracking of intraaortal injected iron oxide-labeled mesenchymal stem cells (MSC) into rats with acute kidney injury (AKI). MATERIALS AND METHODS: In vitro MRI and R2* measurement of nonlabeled and superparamagnetic iron oxide (SPIO)-labeled MSC (MSC(SPIO)) was performed in correlation to cellular iron content and cytological examination (Prussian blue, electron microscopy). In vivo MRI and R2* evaluation were performed before and after ischemic/reperfusion AKI (N = 14) and intraaortal injection of 1.5 x 10(6) MSC(SPIO) (N = 7), fetal calf serum (FCS) (medium, N = 6), and SPIO alone (N = 1) up to 14 days using a clinical 3T scanner. Signal to noise ratios (SNR), R2* of kidneys, liver, spleen, and bone marrow, renal function (creatinine [CREA], blood urea nitrogen [BUN]), and kidney volume were measured and tested for statistical significance (Student's t-test, P < 0.05) in comparison histology (hematoxylin and eosin [H&E], Prussian blue, periodic acid-Schiff [PAS], CD68). RESULTS: In vitro, MSC(SPIO) showed a reduction of SNR and T2* with R2* approximately number of MSC(SPIO) (R2 = 0.98). In vivo MSC(SPIO) administration resulted in a SNR decrease (35 +/- 15%) and R2* increase (101 +/- 18.3%) in renal cortex caused by MSC(SPIO) accumulation in contrast to control animals (P < 0.01). Liver, spleen, and bone marrow (MSC(SPIO)) showed a delayed SNR decline/R2* increase (P < 0.05) resulting from MSC(SPIO) migration. The increase of kidney volume and the decrease in renal function (P < 0.05) was reduced in MSC-treated animals. CONCLUSION: Qualitative and quantitative in vivo cell-tracking and monitoring of organ distribution of intraaortal injected MSC(SPIO) in AKI is feasible in MRI at 3T.  相似文献   
63.
Zander R 《Der Anaesthesist》2007,56(9):912-916
Under laboratory conditions, it can be demonstrated within sufficient clinical accuracy that the base excess (BE, [mmol/l]) is independent of temperature. In any blood gas analyzer with temperature correction, the results are consistent with tonometry when measuring a sample of hypothermic equilibrated blood at 37 degrees C. Under clinical conditions, it is shown that there is practically no difference in the CO(2) partial pressure, irrespective of whether measured directly by capnometry (p(et)CO(2)) or obtained from arterial blood (p(a)CO(2)) in the blood gas analyzer after correction for the patient's temperature. Hence, the clinical recommendations for hypothermia are: correct artificial ventilation, preferably pCO(2) 40+/-5 mmHg, should be established by capnometry and controlled by temperature-corrected p(a)CO(2): metabolic changes should be diagnosed by temperature-independent BE: the temperature-corrected pH, if at all, should be used only for the diagnosis of acidosis or alkalosis.  相似文献   
64.
Although umbilical cord blood (UCB) has been widely accepted as an alternative source of hematopoietic stem cells (HSC) for transplantation, its use in adults is restricted because of low absolute HSC numbers. To overcome this obstacle, expansion of HSC in coculture with feeder cells is a promising possibility. In this study, we compared the potential of three human primary cell types, namely, mesenchymal stem cells (MSC), human umbilical cord vein endothelial cells (HUVEC), and Wharton's jelly cells (WJC), for use as feeder cells in a potentially clinically applicable coculture system. In first experiments, we evaluated procedures needed to obtain feeder cells, the possibility to separate them from cells derived from CD34(+) cells after coculture, their ability to activate allogeneic T cells, and their survival in CD34(+)-adapted medium. Finally, we compared their support for UCB-derived CD34(+) expansion. MSC and WJC were superior to HUVEC in terms of ease and reliability of isolation procedures needed. None of the potential feeder cells expressed CD34 or CD45, thus providing markers for cell sorting after coculture. Other markers (CD31, CD90, CD105, CD166) were expressed differently on feeder cell types. While MSC in higher concentrations did not activate allogeneic T cells, those were stimulated by lower concentrations of MSC as shown by CD25, CD69, and CD71 expression. In contrast, HUVEC and WJC were proven to activate T cells at all ratios tested. Feeder cells survived a 7-day culture in CD34(+)-adapted medium. In cocultures of UCB CD34(+)cells with primary feeder cells, mononuclear cell expansion was 30- to 60-fold, colony-forming cell expansion 20- to 40-fold, and cobblestone area-forming cell expansion 10- to 50-fold. We conclude that after a careful further evaluation especially of their immunological properties, all three primary cell types might possibly be suitable for use in a potentially clinically applicable system for expansion from UCB CD34(+)cells, with WJC being best choice and MSC still superior to HUVEC.  相似文献   
65.
Invasive aspergillosis (IA) is a major cause of mortality in immunocompromised patients. Substantial improvements of treatment have been achieved by the introduction of new antifungal agents including azoles (e.g. posaconazole) and echinocandins (e.g. caspofungin). However, mortality associated with treatment-refractory aspergillosis remains high. Preliminary data suggest that the combination of azoles and echinocandins may increase activity against refractory IA. The objective of the present study was to evaluate efficiency and safety of caspofungin plus posaconazole for salvage therapy in immunocompromised patients. In this monocentric, retrospective study, 31 hospitalised haematopoietic stem cell transplant recipients with IA refractory to primary treatment were treated with a combination therapy of caspofungin 50 mg a day and posaconazole 200 mg four times per day. Efficacy was assessed by signs, symptoms and the degree of pulmonary infiltrate regression. A favourable response was seen in the majority of patients (77%). In two patients (6%), clinical improvement, but no decline in pulmonary infiltrates, was observed. Five patients (16%) did not respond to combination therapy with a fatal outcome in four of them. Combination therapy was well tolerated. No patient discontinued treatment due to toxicity. This study indicates that the combination of caspofungin and posaconazole may provide an effective and tolerable therapy of IA in immunocompromised patients refractory to primary treatment.  相似文献   
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67.
After several years of preparation the German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für An?sthesiologie und Intensivmedizin--DGAI) has, during its annual conference 2007, officially launched the DGAI CPR registry. After implementation of the dataset "primary care" in 2004, the datasets "definite care" and "long-term process" have now been released. The completed, internet based database is open for any interested person or institution as a tool for quality management. Data may be recorded online, and basic analyses be performed immediately. Beyond that benchmarks with other institutions are possible, by including the well accepted Utstein style on international level too.  相似文献   
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70.
Five drugs, selected because of minimal in vivo myelotoxicity, have been investigated for inhibition of the growth of three acute lymphatic leukemia-derived cell lines. Granulocyte-macrophage colony-forming units (GM-CFU) inhibition with these five drugs after 60-min incubation was first established. Drug concentrations giving up to 90% kill of GM-CFU were then used. Spirogermanium and L-asparaginase did not have an effect on any of the three cell lines under the culture conditions tested, while 4-hydroperoxycyclophosphamide (4-HC) and vincristine inhibited the growth of all three cell lines tested, and bleomycin inhibited the growth of two cell lines. In addition to 4-HC, bleomycin and vincristine should be considered as possible agents in eliminating leukemic cells from autologous marrow grafts. These drugs also deserve further investigation in clonal systems.  相似文献   
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