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11.
Background and objectives: The aim of this study was to evaluate the practical value of the dermatoscopic classification of Clark nevi Patients and methods: Dermatoscopic images of 268 lesions clinically and dermatoscopically diagnosed as Clark nevi were presented to 2 dermatologists without knowledge of the histological diagnosis. The dermatologists evaluated the lesions according to a simplified version of the classification scheme for Clark nevi proposed by Hofmann‐Wellenhof and differentiated between 12 different types of Clark nevi. Results: The most common type of Clark nevus was the reticular‐homogenous type (n = 64, 23,9 %), followed by the globular‐homogeneous type (n = 32, 12 %) and by the homogenous type (n = 30, 11,2 %). The overall inter‐rater agreement between the examiners was moderate to good (kappa = 0,58). The highest level of agreement was found for the peripheral hyperpigmented type (kappa = 0,83). Histologically, 17 lesions (6,3 %) were diagnosed as melanomas. The frequency of melanoma was highest among the peripheral‐hyperpigmented type for one observer and among the homogenous type for the other observer. No melanoma was found among the globular, reticular‐globular, and the central‐hyperpigmented types. Conclusions: A dermatoscopic classification of Clark nevi is practically feasible and allows – to some extent – a risk stratification of Clark nevi, which could be useful for clinical management.  相似文献   
12.
Background: In patients with bronchial hyperreactivity, airway instrumentation can evoke life-threatening bronchospasm. However, the best strategy for the prevention of bronchospasm has not been defined. Therefore, in a randomized, prospective, placebo-controlled study, the authors tested whether prophylaxis with either combined salbutamol-methylprednisolone or salbutamol alone (1) improves lung function and (2) prevents wheezing after intubation.

Methods: Thirty-one patients with partially reversible airway obstruction (airway resistance > 180%, forced expiratory volume in 1 s [FEV1] < 70% of predicted value, and FEV1 increase > 10% after two puffs of salbutamol), who were naive to anti-obstructive treatment, were randomized to receive daily for 5 days either 3 x 2 puffs (0.2 mg) of salbutamol alone (n = 16) or salbutamol combined with methylprednisolone (40 mg/day orally) (n = 15). Lung function was evaluated daily. Another 10 patients received two puffs of salbutamol 10 min before anesthesia. In all patients, wheezing was assessed before and 5 min after tracheal intubation.

Results: Within 1 day, both salbutamol and salbutamol-methylprednisolone treatment significantly improved airway resistance (salbutamol, 4.3 +/- 2.0 [SD] to 2.9 +/- 1.3 mmHg [middle dot] s [middle dot] l-1; salbutamol-methylprednisolone, 5.5 +/- 2.9 to 3.4 +/- 1.7 mmHg [middle dot] s [middle dot] l-1) and FEV1 (salbutamol, 1.79 +/- 0.49 to 2.12 +/- 0.61 l; salbutamol-methylprednisolone, 1.58 +/- 0.66 to 2.04 +/- 1.05 l) to a steady state, with no difference between groups. However, regardless of whether single-dose salbutamol preinduction or prolonged salbutamol treatment was used, most patients (8 of 10 and 7 of 9) experienced wheezing after intubation. In contrast, only one patient receiving additional methylprednisolone experienced wheezing (P = 0.0058).  相似文献   

13.
Background: Pimecrolimus cream 1% has proven to be well‐tolerated and effective in controlled clinical studies in patients with atopic dermatitis (AD). In a 15‐week patient self‐observation study, safety and efficacy was investigated in the daily practice. Patients and methods: 3502 patients with AD (mean age 26.2 ± 18 years, 62% female) received pimecrolimus cream 1% from 810 physicians in the German Federal Republic.The severity of the disease was assessed at baseline, two times during the 15‐week observation period and at the end of treatment.Patients recorded daily the degree of erythema and pruritus. At the end of treatment, safety and efficacy were assessed by the physician based on patient's daily records and by the patient. Results: The percentage of patients with severe or massive AD decreased from 25% to 7%, whereas the percentage of patients without or with mild symptoms increased from 9% to 55%.The efficacy of treatment was rated by physicians as good or very good in 83.5% of cases and by 79% of patients.At baseline 35% of the patients were free of flares as compared to 75% at the end of therapy. Disease control was better in patients who followed the recommended treatment algorithm for pimecrolimus cream.Tolerability was mostly rated as good or very good. Conclusion: Treatment with pimecrolimus cream 1% for patients with AD is well‐tolerated and effective in daily practice.  相似文献   
14.
15.
The elderly account for an ever-increasing proportion of emergency department patients. Demographic data show that the population which is 80 years of age or older will be further increasing in coming years. Due to this fact we sought the reasons of using of the emergency department by elderly patients (≥80 years), admitted by ambulance service, and to analyse the general management of this collective according to a younger comparison group. We used the data from a prospective registry, in which all consecutive patients admitted to the emergency department by ambulance service were included, to process this retrospective analysis. In this registry, diagnosis (in the ICD-10 classification), age, sex, and inpatient/outpatient treatment were documented. In addition further management, intensive care treatment, and outcome during emergency department stay were registered. The patients were stratified by age into two groups (< 80 years; ≥80 years). The observation period lasted from January 1, 2005 to December 31, 2005. During the study 6590 patients were observed of whom 5670 patients (86.0%) were under 80 years (PG<80) and 920 (14.0%) were 80 years of age or older (PG≥80). Comparing inpatient treatment (PG<80: 40.1%; PG≥80: 39.8%) vs outpatient treatment (PG<80: 59.9%; PG≥80: 60.2%) no significant difference between both groups was registered. In comparing the ICD- 10 main diagnosis categories, no relevant difference could be ascertained. By contrast a significantly higher mortality (3.0% vs 1.6%; p≤0.01) in the emergency department was shown within the PG≥80, especially if the diagnosis was myocardial infarction or stroke. The most frequent discharge diagnosis in the PG≥80 was acute myocardial infarction (6.7%). A percutaneous coronary intervention and artificial respiration was less frequently used in the elderly group. Patients beyond 80 years of age nowadays constitute a remarkable proportion of emergency department patients admitted by ambulance service. This group does not differ substantially from younger patients, neither in questions of inpatient or outpatient treatment nor in types of diagnosis. Elderly patients in the emergency department showed a higher mortality. Invasive interventions were less frequently used in this collective in comparison to younger patients. In consideration of the fact that the proportion of elderly will further increase in our population, this analysis may give basis for development of new strategies for the treatment of old patients in emergency departments.  相似文献   
16.
PURPOSE: This paper briefly summarizes the research on increased radiosensitivity in breast cancer patients measured by the micronucleus test (MNT) and its association to genetic variants in DNA repair genes. More preliminary data are presented on the distribution of chromosomes and chromosome fragments in micronuclei (MN) in order to gain more information on clastogenic and aneugenic effects and better understand the phenotype of increased radiosensitivity. MATERIAL AND METHODS: Reports of relevant studies obtained from a search of PubMed and studies referenced in those reports were reviewed. In four patients with high MN frequency (three cancer patients, one control) and four probands with low MN frequency, the presence of chromosome fragments or whole chromosomes in MN was determined by fluorescence in situ hybridization analysis for chromosomes 1, 7, and 17. RESULTS: An increased MN frequency in breast cancer patients compared to controls has consistently been reported with high significance. Higher MN frequencies were observed in 20-50% of breast cancer patients. Chromosomal fragments of chromosome 17, but not of chromosomes 1 and 7 were more frequent in the probands with high MN frequency than in those with low frequency (p = 0.045). CONCLUSION: The MNT detects a cellular phenotype common to a portion of sporadic breast cancer patients. This phenotype is very likely to be genetically determined. For the genetic dissection of breast cancer susceptibility this phenotype may turn out to be more efficient than breast cancer itself. Additional parameters which can be measured simultaneously with the MN frequency may be able to further enhance its usefulness.  相似文献   
17.
PURPOSE: To evaluate the precision of image-guided radiotherapy (IGRT) using cone-beam computed tomography (CB-CT) for volume imaging and a robotic couch for correcting setup errors in six degrees of freedom. PATIENTS AND METHODS: 47 consecutive patients with 372 fractions were classified according to whether a patient fixation device was used (pat(fix): n = 28) or not (pat(non-fix): n = 19). Prior to treatment a CB-CT was acquired and translational and rotational setup errors were corrected online without an action level using a robotic couch (HexaPOD). A second CB-CT was acquired after the correction process and after treatment in 134 and 238 fractions, respectively. RESULTS: In 17 fractions (4.6%) rotational errors > 3 degrees exceeded the motion range of the HexaPOD. Errors (3D vector) after the correction process were significantly smaller for pat(fix) compared to pat(non-fix) (p < 0.001): 0.9 mm +/- 0.5 mm and 1.6 mm +/- 0.8 mm, respectively. For pat(non-fix) the correction of rotational errors resulted in displacements of the patients on the angled couch of 0.6 mm/1 degree. Intrafractional motion further decreased precision in pat(non-fix) but not in pat(fix). CONCLUSION: Very high precision in cranial and extracranial treatment of immobilized patients was demonstrated. Without application of adequate immobilization the correction of rotational errors and intrafractional patient motion significantly decreased the accuracy of the online correction protocol.  相似文献   
18.
The pathomechanisms involved in the neuronal dysfunction in Huntington disease (HD) are still unresolved and may be heterogeneous. One potential mechanism might be related to the induction of mitochondrial dysfunction in the CNS. This might lead firstly to neuronal dysfunction and finally to the activation of apoptotic pathways. Several compounds, which should alleviate mitochondrial dysfunction, have been tested in preclinical models as well as in clinical trials of different scale. Recently we reported the efficacy of Ethyl-eicosapentaenoic acid (Ethyl-EPA) in patients with HD. Ethyl-EPA is a polyunsaturated fatty acid from the n − 3 group, which is in clinical development for HD and melancholic depression. In our trial with Ethyl-EPA in HD responding patients could be characterized by either a lower CAG repeat number or a chorea-predominant clinical expression of the disease. Here we would like to describe some evidence on the potential mechanism of action of Ethyl-EPA in HD. We specifically focus on pathways, which are known to be influenced in HD and are modified by Ethyl-EPA and which points to an involvement of mitochondrial function as a common target. Some attention is given to the NF-kappa B pathway and the c-Jun amino-terminal kinases (JNK) pathway, which both may lead to an activation of the antiproliferative factor p53 and consequently mitochondrial dysfunction. Further the effects of EPA or Ethyl-EPA in preclinical models of HD are described. The evidence from these studies led to the design of phase III clinical trials, which are ongoing.  相似文献   
19.
Decrease of glucose in the human visual cortex during photic stimulation.   总被引:4,自引:0,他引:4  
Localized proton NMR spectroscopy was used to study cerebral metabolism in the visual cortex of healthy adults during rest and photic stimulation. Basal lactate levels showed considerable interindividual differences ranging from below detectability (less than 0.3 mM) to about 1 mM without consistent alteration during photic stimulation. Local brain glucose levels were significantly reduced (approximately 50%) during the entire period of photic stimulation and recovered to resting levels (approximately 0.8 mM) within 10 min after the end of stimulation. This decrease reflects the establishment of a new equilibrium due to enhanced delivery (blood flow) and enhanced consumption. The absence of lactate accumulation supports the hypothesis of a rapid efflux of lactate from brain tissue under activated conditions.  相似文献   
20.
Intraoperative blood salvage in cancer surgery: safe and effective?   总被引:5,自引:0,他引:5  
To support blood supply in the growing field of cancer surgery and to avoid transfusion induced immunomodulation caused by the allogeneic barrier and by blood storage leasions we use intraoperative blood salvage with blood irradiation. This method is safe as it provides efficient elimination of contaminating cancer cells, and as it does not compromise the quality of RBC. According to our experience with more than 700 procedures the combination of blood salvage with blood irradiation also is very effective in saving blood resources. With this autologous, fresh, washed RBC a blood product of excellent quality is available for optimal hemotherapy in cancer patients.  相似文献   
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