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1.
Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposing factor.  相似文献   
2.
One serious complication of neurofibromatosis type 1 (NF1) is the development of malignant peripheral nerve sheath tumours (MPNSTs). These malignancies often develop within pre-existing plexiform neurofibromas and their development is now thought to be associated with both tumour suppressor gene mutations and dysregulated growth factor signalling. Recent work demonstrates that the lifetime risk of malignant transformation is significantly greater than previously thought. Ionising radiation, a long-standing disease, particularly the presence of a large number of plexiform neurofibromas from an early age, are suggested risk factors. We present an NF1 patient who developed an MPNST of the cervical vagus nerve which was successfully treated with surgery. Close monitoring of patients with NF and a high level of suspicion towards rapidly enlarging and painful swellings is merited as these features may signify malignant transformation. Whether a positive history of MPNST in other affected family members predisposes the individual to a higher risk of malignant transformation is unclear.  相似文献   
3.
The techniques of haemapheresis originated in the development of centrifugal devices separating cells from plasma and later on plasma from cells. Subsequently membrane filtration was developed allowing for plasma-cell separation. The unspecificity of therapeutic plasma exchange led to the development of secondary plasma separation technologies being specific, semi-selective or selective such as adsorption, filtration or precipitation. In contrast on-line differential separation of cells is still under development. Whereas erythrocytapheresis, granulocytapheresis, lymphocytapheresis and stem cell apheresis are technically advanced, monocytapheresis may need further improvement. Also, indications such as erythrocytapheresis for the treatment of polycythaemia vera or photopheresis though being clinically effective and of considerable importance for an appropriate disease control are to some extent under debate as being either too costly or without sufficient understanding of the mechanism. Other forms of cell therapy are under development. Rheohaemapheresis as the most advanced technology of extracorporeal haemorheotherapy is a rapidly developing approach contributing to the treatment of microcirculatory diseases and tissue repair. Whereas the control of a considerable number of (auto-) antibody mediated diseases is beyond discussion, the indication of apheresis therapy for immune complex mediated diseases is quite often still under debate. Detoxification for artificial liver support advanced considerably during the last years, whereas conclusions on the efficacy of septicaemia treatment are debatable indeed. LDL-apheresis initiated in 1981 as immune apheresis is well established since 24 years, other semi-selective or unspecific procedures, allowing for the elimination of LDL-cholesterol among other plasma components are also being used. Correspondingly Lp(a) apheresis is available as a specific, highly efficient elimination procedure superior to techniques which also eliminate Lp(a). Quality control systems, more economical technologies as for instance by increasing automation, influencing the over-interpretation of evidence based medicine especially in patients with rare diseases without treatment alternative, more insight into the need of controlled clinical trials or alternatively improved diagnostic procedures are among others tools ways to expand the application of haemapheresis so far applied in cardiology, dermatology, haematology, immunology, nephrology, neurology, ophthalmology, otology, paediatrics, rheumatology, surgery and transfusion medicine.  相似文献   
4.
We report on 9 patients with pilomatricomas that showed unusual histopathologic features. Our patients were mainly elderly individuals (age range 42 to 88 years; mean age 70.1 years) who presented solitary cutaneous nodules situated on the head and neck (7 neoplasms), upper arm (1 neoplasm), and back (1 neoplasm). All the lesions were treated by simple excision. Follow-up data available in 7 of the 9 patients (mean follow-up, 17 months) revealed local recurrences in 1 patient whose lesion recurred 3 times. No lymph node involvement or distant metastases were recorded in any of our cases. Histopathologically, most neoplasms were characterized by a relatively large lesion in the clermis that in some cases showed extension to the subcutis. Each lesion was predominantly composed of a lobular proliferation of basaloid cells in association with adjacent focal areas containing eosinophilic, cornified material with shadow cells. In some cases, relatively large areas of shadow cells were present, whereas, in others only small foci of shadows cells were observed. Cytomorphologically, the basaloid cells showed features of matrical and supramatrical cells of a normal hair follicle and exhibited variable nuclear atypia and mitotic figures. The overall architectural pattern of the neoplasms was different from that of large fully developed stereotypical pilomatricomas that maintain a cystic character with basaloid cells predominantly aligned at the periphery. Based on the histopathologic findings, namely the presence of a large, lobular proliferation of basaloid cells in association with small to large foci of shadow cells, we interpreted these neoplasms to be a distinctive proliferative variant of pilomatricoma and propose the designation "proliferating pilomatricoma." Proliferating pilomatricomas should be differentiated from the recently described matricoma, basal-cell carcinoma with matrical differentiation, and matrical carcinoma (pilomatrical carcinoma).  相似文献   
5.
Trauma und Berufskrankheit - Zusammenfassung Die angemessene Behandlung der Radiusköpfchenfrakturen erfolgt nach korrekter Klassifikation unter Berücksichtigung von Begleitverletzungen...  相似文献   
6.
Lesion evolution during focal cerebral ischemia may depend on flow restrictions or on accumulation of toxic mediators within the infarct and expansion of these factors to the periinfarct region. So far, the precise contribution of flow dependent versus spreading-mediated impairment of viable periinfarct tissue has not been determined. Therefore, we measured lesion expansion, flow restrictions and glutamate distribution on serial brain sections at different time points after experimental focal ischemia.Permanent focal ischemia was induced by occlusion of the right middle cerebral artery in male rats and the flow reduction was subsequently measured at 1, 12 and 24 h using iodo[14C]antipyrine autoradiography. Additionally, the necrotic volume was determined on serial brain sections and the glutamate content was measured in tissue samples from adjacent microdissections.Twelve hours after focal ischemia no noteworthy viable areas with blood flow restrictions of 20-40 ml 100 g− 1 min− 1 existed but at 24 h the necrotic tissue exceeded the hemodynamically compromised region by 40 ± 21 mm3 (24%). Furthermore, at 12 and 24 h the glutamate content was elevated in areas surrounding the infarct.Relevant flow restrictions are detectable only during early stages of infarct maturation, whereas the propagation of secondary factors may be the predominant mechanism for delayed infarct evolution.  相似文献   
7.
8.
BACKGROUND: An objective of exercise-based cardiac rehabilitation is improvement in patient-reported outcomes such as health-related quality of life as well as anxiety and depressive symptoms. There are no direct comparisons of the effectiveness of inpatient and outpatient exercise-based cardiac rehabilitation programmes on patient-reported outcomes. METHODS: In this non-randomized study we collected patient-reported outcomes data with the MacNew Heart Disease health-related quality of life questionnaire and the Hospital Anxiety and Depression Scale at baseline, 1 month and again 3 months after admission to exercise-based cardiac rehabilitation in a cohort of 216 consecutive patients enrolled either in a 4-week inpatient exercise-based cardiac rehabilitation (n=62) or a 3-month outpatient exercise-based cardiac rehabilitation (n=87) and in a usual care group (n=67) to document the natural course in patient-reported outcome variables without exercise-based cardiac rehabilitation. RESULTS: Although MacNew health-related quality of life scores improved more with inpatient than outpatient exercise-based cardiac rehabilitation by month 1, the improvement was still significant in both groups at month 3 and also in the usual care group when compared to baseline. The health-related quality of life scores in the inpatient group, however, decreased between month 1 and 3 whereas they continued to improve in the outpatient group. The significant reduction in both anxiety and depressive symptoms in both exercise-based cardiac rehabilitation groups by month 1 was maintained at month 3 only with outpatient exercise-based cardiac rehabilitation. No significant changes over the 3 months were observed in the usual care group. CONCLUSION: Significant improvements of 1-month patient-reported outcomes are achieved in patients attending inpatient as well as outpatient exercise-based cardiac rehabilitation when compared with no exercise-based cardiac rehabilitation. In contrast to inpatient exercise-based cardiac rehabilitation, however, outpatient exercise-based cardiac rehabilitation leads to a further improvement of patient-reported outcomes. These results suggest that, if patients have to be admitted for inpatient exercise-based cardiac rehabilitation, this programme should be followed by an outpatient exercise-based cardiac rehabilitation to further improve and stabilize these patient-reported outcome variables.  相似文献   
9.
OBJECTIVE: Biventricular pacing has demonstrated improvement in cardiac function in treating congestive heart failure (CHF). Two different operative strategies (coronary sinus vs. epicardial stimulation) for left ventricular (LV) pacing were compared. METHODS: Since April 1999, a total of 86 patients (pts, age: 63+/-10 years) with depressed systolic LV function (mean ejection fraction 24+/-9%), left bundle-branch-block (mean QRS 182+/-22 ms) and congestive heart failure NYHA III or higher were enrolled. For biventricular stimulation coronary sinus (CS) leads were placed in 79 pts. Nine of these devices were converted to surgical epicardial LV-leads, because of CS-lead failure. In 7 patients epicardial LV-leads were initially implanted surgically, accounting for a total of 16 pts with surgical placed epicardial steroid-eluting LV-leads. For these, a limited left-lateral thoracotomy (7+/-4 cm) was used. Thirty-three (38%) pts had an indication for a defibrillator. The mean follow-up time was 16.4+/-15.4 months (0.1-45 months), representing 107.1 patient-years. RESULTS: In the biventricular pacing mode, QRS duration decreased to 143+/-16 ms (P<0.001). Threshold capture of the CS-leads increased significantly compared to surgically placed epicardial leads (18 month control: 2.2+/-1.4V/0.5 ms vs. 0.7+/-0.3V/0.5 ms), which had no increase in threshold (P<0.001). At the 18 month follow-up 7 CS-leads had a threshold of >4V/0.5 ms vs. epicardial leads which were under 1.1V/0.5 ms, except for one (1.8V/0.5 ms). After CS-lead implantation 25 LV-lead related complications occurred, (failed implantation, CS-dissection, loss of pacing capture, diaphragm stimulation or lead dislodgment), vs. one dislodgement after surgical epicardial lead placement (P<0.05). Correct lead positioning (obtuse marginal branch area) was achieved in all surgical epicardial placements but only in 70% with CS-leads (P<0.03). In the follow up period, 9 pts died (4 cardiac related). Heart transplantation was necessary in 4 pts due to deterioration of the cardiomyopathy. CONCLUSIONS: Surgical epicardial lead placement revealed excellent long-term results and a lower LV-related complication rate compared to CS-leads. Although, the approach via limited thoracotomy for biventricular pacing is associated with 'more surgery', it is a safe and reliable technique and should be considered as an equal alternative.  相似文献   
10.
STUDY OBJECTIVE--The aim was to investigate the antiarrhythmic effects of (+)- and (-)-naloxone in various arrhythmia models in vivo. DESIGN--Naloxone (1-40 mg.kg-1), naltrexone (20-40 mg.kg-1), or standard antiarrhythmic drugs (quinidine, lignocaine, phenytoin, (+)-sotalol) were injected intravenously. Ventricular extrasystoles were then elicited by infusion of either ouabain (guinea pigs) or aconitine (rats), or by electrical stimulation (guinea pigs). EXPERIMENTAL MATERIAL--Male Wistar rats and guinea pigs (n = 6-10) were used. Arterial blood pressure and ECG were recorded continuously. MEASUREMENTS AND MAIN RESULTS--Naloxone and naltrexone decreased the heart rate. The effect of naloxone was not stereospecific and is apparently not mediated by opioid receptors. Naloxone had no influence on ouabain induced arrhythmias or fibrillation threshold in guinea pigs. The appearance of aconitine induced extrasystoles was accelerated by 20 mg.kg-1 (-)-naloxone but delayed by 40 mg.kg-1. No effects were seen with (+)-naloxone or (-)-naltrexone. CONCLUSIONS--The results show that naloxone does not possess prominent antiarrhythmic properties.  相似文献   
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