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51.
Summary Acute leukaemia was complicated by pneumonia in 38 (34.8%) of 109 patients treated between 1979 and 1983; in 39.5% of the patients pneumonia occurred more than once. In 23 patients (60.5%) pneumonia occurred during cytostatic therapy, and 25 patients (65.8%) had less than 1000 mm2 granulocytes. Antibiotic therapy had no or only little effect in 70%. A total of 21 patients (55.3%) died of pneumonia. In 15 patients a direct relationship could be seen between pneumonia and the bacterial spectrum in the sputum. A prevalence of gram-negative bacteria was found (24 of 40 bacteria isolated, especially Enterobacteriaceae (19). Fungi were cultivated in 10 cases. Each of the typical pneumonia bacteria was only seen once respectively. It is most important that therapy begin immediately, even before the bacteria have been identified. Only then is there hope that the survival time of patients with acute leukaemia can be influenced.
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Synthetic calcium phosphate bone void fillers promote varying rates of bone formation and material resorption depending on chemistry, porosity, pore structure, and implant site. The objective of this study was to quantify the resorption of a novel ultraporous beta-tricalcium phosphate cancellous bone void filler with simultaneous quantification of bone formation in a canine humerus model. Potential measurement error involved in conventional histomorphometry using Von Kossa stains inspired the development of a new technique. This technique utilizes bright-field and polarized-light microscopy in conjunction with image analysis software, allowing more accurate histomorphometry. This technique was validated with two separate controlled experiments. Scanning electron microscopy further supported the results. The findings suggest that the use of polarized-light microscopy combined with image analysis software can be an effective tool in simultaneously quantifying calcium phosphate resorption and bone formation.  相似文献   
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Pflügers Archiv - European Journal of Physiology - According to earlier studies on mammalian papillary muscles, Ni and Co ions reduce the Ca dependent mechanical response whilst the action...  相似文献   
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In cirrhotic patients, plasma amino acid levels are severely deranged. A decreased ratio of branched-chain to aromatic amino acids (Fischer ratio) has been implicated in the pathogenesis of hepatic encephalopathy. In this prospective study, we investigated the effects of extracorporeal detoxification on amino acid levels using a sorbent suspension dialysis system. Twenty patients with documented cirrhosis and hepatic encephalopathy grade II-III not responding to standard treatment were randomized to receive either six hours of sorbent dialysis and standardized conventional medical treatment or ongoing medical treatment alone. In contrast to previous uncontrolled studies, no significant effect on amino acid levels, Fischer ratio or clinical grade of hepatic encephalopathy was detected in either treatment group. In conclusion, a 6-hour treatment with sorbent dialysis did not significantly influence plasma levels of amino acids and did not ameliorate the clinical grade of hepatic encephalopathy.  相似文献   
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Although the cerebellum has been shown to be critical for the acquisition and retention of adaptive modifications in certain reflex behaviors, this structures role in the learning of motor skills required to execute complex voluntary goal-directed movements still is unclear. This study explores this issue by analyzing the effects of inactivating the interposed and dentate cerebellar nuclei on the adaptation required to compensate for an external elastic load applied during a reaching movement. We show that cats with these nuclei inactivated can adapt to predictable perturbations of the forelimb during a goal-directed reach by including a compensatory component in the motor plan prior to movement initiation. In contrast, when comparable compensatory modifications must be triggered on-line because the perturbations are applied in randomized trials (i.e., unpredictably), such adaptive responses cannot be executed or reacquired after the interposed and dentate nuclei are inactivated. These findings provide the first demonstration of the condition-dependent nature of the cerebellums contribution to the learning of a specific volitional task.  相似文献   
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Transgenic rat model of Huntington's disease   总被引:12,自引:0,他引:12  
Huntington's disease (HD) is a late manifesting neurodegenerative disorder in humans caused by an expansion of a CAG trinucleotide repeat of more than 39 units in a gene of unknown function. Several mouse models have been reported which show rapid progression of a phenotype leading to death within 3-5 months (transgenic models) resembling the rare juvenile course of HD (Westphal variant) or which do not present with any symptoms (knock-in mice). Owing to the small size of the brain, mice are not suitable for repetitive in vivo imaging studies. Also, rapid progression of the disease in the transgenic models limits their usefulness for neurotransplantation. We therefore generated a rat model transgenic of HD, which carries a truncated huntingtin cDNA fragment with 51 CAG repeats under control of the native rat huntingtin promoter. This is the first transgenic rat model of a neurodegenerative disorder of the brain. These rats exhibit adult-onset neurological phenotypes with reduced anxiety, cognitive impairments, and slowly progressive motor dysfunction as well as typical histopathological alterations in the form of neuronal nuclear inclusions in the brain. As in HD patients, in vivo imaging demonstrates striatal shrinkage in magnetic resonance images and a reduced brain glucose metabolism in high-resolution fluor-deoxy-glucose positron emission tomography studies. This model allows longitudinal in vivo imaging studies and is therefore ideally suited for the evaluation of novel therapeutic approaches such as neurotransplantation.  相似文献   
59.
Summary The hemagglutination of human and rat red blood cells by adeno-virus type 27 is completely inhibited by treatment of the virus with p-chlormercuribenzoic acid (PCMB), N-ethylmaleimid (NEM) and KJO4. Treatment of the erythrocytes has no effect. The action of PCMB and NEM is fully reverted by reduced glutathione or 1-cysteine. Under the same conditions, the hemagglutinins of other adenovirus types belonging also toRosen's group II are unaffected by these reagents.

Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
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