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排序方式: 共有368条查询结果,搜索用时 31 毫秒
1.
Clinical trials are the most widely accepted tools in the search for more effective supportive care drugs/interventions. The aim of our study was to determine Central Eastern European countries' (CEEC) involvement and future interest in conducting supportive care clinical trials. Our study was a part of an ESMO/MASCC program launched to support the development of supportive care in CEEC. The study was designed as a mailed questionnaire survey within the ESMO CEE Task Force. It involves national representatives from 18 countries. The purpose of the questionnaire was to assess the involvement and interest in conducting clinical trials in 13 representative supportive care fields: antiemetic therapy, cancer pain control, infections/febrile neutropenia, mucositis, fatigue, hypercalcemia, dyspnea, anorexia/cachexia, psychosocial support, toxicity reducing agents, hematopoietic growth factors, communication/education and quality of life. A total of 15 completed questionnaires were returned (83.3%). CEEC were mainly involved in clinical trials of hematopoietic growth factors (7/15), quality of life (6/15), antiemetic therapy (5/15), and cancer pain control (4/15). Increased interest was observed in the trials of fatigue, dyspnea, psychosocial support, infections / febrile neutropenia, communication / education and toxicity reducing agents. Clusters of CEEC that are similar in terms of their previous involvement and future interest in supportive care trials were identified. Our survey may prove to be a significant first step for CEEC active involvement in multinational clinical trials, which are crucial for improving supportive care standards.  相似文献   
2.
Background: The Na sup + channel is voltage gated and characterized by three distinct states: closed, open, and inactivated. To identify the effects of halothane on the cardiac Na sup + current (INa) at various membrane potentials, the effects of 1.2 mm halothane at different holding potentials (VH) on INa were examined in single, enzymatically isolated guinea pig ventricular myocytes.

Methods: The INa was recorded using the whole-cell configuration of the patch-clamp technique. Currents were generated from resting VH s of -110, -80, or -65 mV. State-dependent block was characterized by monitoring frequency dependence, tonic block, and removal of inactivation by veratridine.

Results: Halothane produced significant (P < 0.05) VH -dependent depressions of peak INa (mean +/- SEM): 24.4 +/- 4.1% (VH = -110 mV), 42.1 +/- 3.4% (VH = -80 mV), and 75.2 +/- 1.5% (VH = -65 mV). Recovery from inactivation was significantly increased when cells were held at -80 mV (control, tau = 6.0 +/- 0.3 ms; halothane, tau = 7.1 +/- 0.4 ms), but not at -110 mV. When using a VH of -80 mV, halothane exhibited a use-dependent block, with block of INa increasing from 8.6 +/- 1.4% to 30.7 +/- 3.5% at test pulse rates of 2 and 11 Hz, respectively. Use-dependent inhibition was not apparent at VH of -110 mV. When inactivation of INa was removed by exposure to 100 micro Meter veratridine, no significant difference was observed in the depressant effect of halothane at both VH s: 26.6 +/- 4.5% (VH = -80 mV) and 26.4 +/- 5.6% (VH = -110 mV).  相似文献   

3.
Background: Pathophysiology in the primary sensory neuron may contribute to chronic neuropathic pain. Ca channels play a central role in neuronal processes, and sensory neurons are rich in low-voltage-activated calcium channels (LVACCs). However, the physiologic function of these channels is unknown. Their possible role in rebound burst firing makes them a candidate for increased excitability after neuropathic injury.

Methods: This study uses pharmacological methods to isolate LVACC in cells from the dorsal root ganglia of neuropathic and sham-operated rats, including the blockade of high-voltage-activated Ca channels with fluoride and selective toxins. LVACCs were examined with conventional whole cell patch clamp electrophysiology techniques.

Results: After chronic constriction injury of the peripheral axon, LVACC was significantly reduced compared to sham rats as shown by a 60% reduction in peak current density and an 80% reduction in total calcium influx. A depolarizing shift in the voltage dependence of activation and an increase in the rate of deactivation and inactivation appear to cause this reduction of LVACC. Either Ni2+ or mibefradil, blockers of LVACC, applied in the bath to normal dorsal root ganglion cells during current clamp significantly and reversibly increased excitability.  相似文献   

4.
Duplication of the long arm of chromosome 1 (1q) is widely reported in human neoplasia, including the myelodysplastic syndromes (MDS). So far, it has not been described as a single aberration in the chronic myelomonocytic leukemia (CMML), a subtype of MDS. Rather, trisomy 1q was always a part of complex chromosome changes affecting the subtypes of MDS other than CMML. We report on a patient with CMML with an unbalanced translocation of the entire 1q onto the short arm of chromosome 14 as a sole cytogenetic abnormality. Fluorescence in situ hybridization (FISH) analysis with an alpha-satellite probe for the paracentric region of the long arm of chromosome 1 confirmed the presence of trisomy 1q in a derivative chromosome, der(14)t(1;14)(q12;p11). The discrepant results between the metaphase cytogenetics (100% abnormal) and interphase cytogenetic (71% nuclei with 3 signals) suggest that trisomy 1q, even in the absence of additional cytogenetic changes, has a sufficient leukemogenic potential to confer a proliferative advantage on hematopoietic cells committed to monocyte stemline both in vitro and in vivo. The literature data on partial and complete trisomy 1q in CMML is reviewed.  相似文献   
5.
Perioperative malignant ventricular tachyarrhythmias pose an imminent clinical danger by potentially precipitating myocardial ischemia and severely compromising hemodynamics. Thus, immediate and effective therapy is required, which is not always provided by currently recommended IV drug regimens, indicating a need for more effective drugs. We examined antiarrhythmic effects of the new benzofurane compound E 047/1 on spontaneous ventricular tachyarrhythmia in a conscious dog model. One day after experimental myocardial infarction, 40 dogs exhibiting tachyarrhythmia randomly received (bolus plus 1-h infusion) E 047/1 6 mg/kg plus 6 mg x kg(-1) x h(-1), lidocaine 1 mg/kg plus 4.8 mg x kg(-1) x h(-1), flecainide 1 mg/kg plus 0.05 mg x kg(-1) x h(-1), amiodarone 10 mg/kg plus 1.8 mg x kg(-1) x h(-1), or bretylium 10 mg/kg plus 20 mg x kg(-1) x h(-1). Electrocardiogram was evaluated for number of premature ventricular contractions (PVC), normally conducted beats originating from the sinoatrial node, and episodes of ventricular tachycardia. Immediately after the bolus, E 047/1 reduced PVCs by 46% and increased sinoatrial beats from 4 to 61 bpm. The ratio of PVCs to total beats decreased from 98% to 58%. Amiodarone and flecainide exhibited antiarrhythmic effects with delayed onset. Lidocaine did not suppress PVCs significantly, and bretylium was proarrhythmic. The antiarrhythmic E 047/1 has desirable features, suppressing ischemia-induced ventricular tachyarrhythmia quickly and efficiently, and may be a useful addition to current therapeutic regimens. IMPLICATIONS: Life-threatening arrhythmias of the heart after myocardial infarction or ischemia may be treated quickly and efficiently by the new drug E 047/1.  相似文献   
6.
Bosnjak R  Dolenc VV 《Spine》2000,25(6):703-708
STUDY DESIGN: A comparison of electrical thresholds for biomechanical response in the ankle and for evoked electromyographic signals from specific leg muscles during intraoperative extradural direct stimulation of roots L4, L5, and S1. OBJECTIVE: To determine whether a biomechanical response in the ankle to direct root stimulation occurs before evoked electromyographic signals and to determine differences in electrical excitability of the roots circumferentially. SUMMARY OF BACKGROUND DATA: Stimulus intensities of 1.2-5.7 mA are reported to evoke electromyographic response in corresponding muscles to direct stimulation of normal roots. Stimulus intensities of 6-8 mA were suggested to detect bony pedicular compromise by stimulation of a hole or a screw during pedicle instrumentation. Electrical thresholds of three-dimensional torque response in the ankle to direct root stimulation have not yet been evaluated and compared with thresholds of evoked electromyogram. METHODS: Direct monopolar stimulation of the surgically exposed roots L4, L5, and S1 was performed from different sites around the root by a cuff multielectrode. Biomechanical response was measured as an isometric torque in the ankle at each of three orthogonal axes. Compound muscle action potentials (CMAPs) from root-specific muscles were detected by a pair of surface or wire electrodes. RESULTS: Mean threshold for biomechanical response in the ankle to stimulation of roots L4, L5, and S1 was 0.72 +/- 0.39 mA and for CMAP response was 1.09 mA +/- 0.36 (N = 13). Thresholds for biomechanical responses were significantly lower than for CMAP responses (P = 0.0004; paired t test). Nerve roots were electrically most excitable on their ventral aspects. CONCLUSION: The biomechanical response in the joint to root stimulation can be used to test all root-related muscles crossing that joint at their individual innervation pattern and their residual innervation and to detect electrical excitation of the root at electric thresholds lower than those for detecting CMAP from single standard root-specific muscle. However, this method does not provide sufficient root specificity. It will be valuable in conjunction with multimodality neurophysiologic monitoring of the roots for earlier and more reliable detection of pedicle bone breakthrough or integrity. Further clinical investigations are suggested.  相似文献   
7.
PURPOSE: To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain. PATIENTS AND METHODS: Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks. RESULTS: A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P =.019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups. CONCLUSION: Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain.  相似文献   
8.
BACKGROUND: The noble gas xenon (Xe) has been used as an inhalational anesthetic agent in clinical trials with little or no physiologic side effects. Like nitrous oxide, Xe is believed to exert minimal unwanted cardiovascular effects, and like nitrous oxide, the vapor concentration to achieve 1 minimum alveolar concentration (MAC) for Xe in humans is high, i.e., 70-80%. In the current study, concentrations of up to 80% Xe were examined for possible myocardial effects in isolated, erythrocyte-perfused guinea pig hearts and for possible effects on altering major cation currents in isolated guinea pig cardiomyocytes. METHODS: Isolated guinea pigs hearts were perfused at 70 mm Hg via the Langendorff technique initially with a salt solution at 37 degrees C. Hearts were then perfused with fresh filtered (40-microm pore) and washed canine erythrocytes diluted in the salt solution equilibrated with 20% O2 in nitrogen (control), with 20% O2, 40% Xe, and 40% N2, (0.5 MAC), or with 20% O2 and 80% Xe (1 MAC), respectively. Hearts were perfused with 80% Xe for 15 min, and bradykinin was injected into the blood perfusate to test endothelium-dependent vasodilatory responses. Using the whole-cell patch-clamp technique, 80% Xe was tested for effects on the cardiac ion currents, the Na+, the L-type Ca2+, and the inward-rectifier K+ channel, in guinea pig myocytes suffused with a salt solution equilibrated with the same combinations of Xe, oxygen, and nitrogen as above. RESULTS: In isolated hearts, heart rate, atrioventricular conduction time, left ventricular pressure, coronary flow, oxygen extraction, oxygen consumption, cardiac efficiency, and flow responses to bradykinin were not significantly (repeated measures analysis of variance, P>0.05) altered by 40% or 80% Xe compared with controls. In isolated cardiomyocytes, the amplitudes of the Na+, the L-type Ca2+, and the inward-rectifier K+ channel over a range of voltages also were not altered by 80% Xe compared with controls. CONCLUSIONS: Unlike hydrocarbon-based gaseous anesthetics, Xe does not significantly alter any measured electrical, mechanical, or metabolic factors, or the nitric oxide-dependent flow response in isolated hearts, at least partly because Xe does not alter the major cation currents as shown here for cardiac myocytes. The authors' results indicate that Xe, at approximately 1 MAC for humans, has no physiologically important effects on the guinea pig heart.  相似文献   
9.
10.
Objective:To determine the difference in the levels of Streptococcus mutans and S sobrinus in stimulated saliva in orthodontic patients with different bracket types (stainless steel and esthetic brackets) using polymerase chain reaction and cultivation method.Materials and Methods:Thirty-two patients, aged 13 to 30 years, were selected following these criteria: 1) orthodontic treatment indication, 2) systemic health, and 3) no tobacco and antibiotic consummation for three months prior to the commencement of the study. Patients were divided into two groups according to the bracket type; 16 patients formed the conventional bracket group (stainless steel brackets), and 16 patients formed the esthetic bracket group (plastic brackets). The levels of S mutans and S sobrinus in stimulated whole saliva samples were collected prior to fixed orthodontic appliance placement (T1) and 12 weeks after placement (T2), as were the Decayed, Missing, and Filled Surface Index (DMFS) and Oral Hygiene Index-Simplified (OHI-S). Mann-Whitney, Wilcoxon, and chi-square tests were used for statistical analysis.Results:Statistical analysis (chi-square test) showed no difference in S mutans and S sobrinus counts among patients with different brackets at either T1 or T2. There was no difference in total bacteria counts after fixed orthodontic appliance placement.Conclusion:The number of colony-forming units of S mutans and S sobrinus in stimulated saliva samples does not seem to be significantly different between patients with stainless steel brackets and patients with plastic brackets.  相似文献   
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