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排序方式: 共有3098条查询结果,搜索用时 15 毫秒
1.
Antony E. Shrimpton Robert L. Schelper Reinhold P. Linke John Hardy Richard Crook Dennis W. Dickson Takashi Ishizawa Richard L. Davis 《Neuropathology》2007,27(3):228-232
Over 100 mutations in the presenilin‐1 gene (PSEN1) have been shown to result in familial early onset Alzheimer disease (EOAD), but only a relatively few give rise to plaques with an appearance like cotton wool (CWP) and/or spastic paraparesis (SP). A family with EOAD, seizures and CWP was investigated by neuropathological study and DNA sequencing of the PSEN1 gene. Aβ was identified in leptomeningeal vessels and in cerebral plaques. A single point mutation, p.L420R (g.1508T > G) that gives rise to a missense mutation in the eighth transmembrane (TM8) domain of PS1 was identified in two affected members of the family. p.L420R (g.1508T > G) is the mutation responsible for EOAD, seizures and CWP without SP in this family. 相似文献
2.
Acetabular blood flow during Bernese periacetabular osteotomy: an intraoperative study using laser Doppler flowmetry. 总被引:2,自引:0,他引:2
Axel Hempfing Michael Leunig Hubert P. Ntzli Martin Beck Reinhold Ganz 《Journal of orthopaedic research》2003,21(6):1145-1150
BACKGROUND: The blood flow to the acetabular fragment is of some concern in juxtaarticular pelvic osteotomies used for the treatment of hip dysplasia. No direct measurements have determined the effect of the Bernese periacetabular osteotomy (PAO) on acetabular perfusion. METHODS: Acetabular perfusion was measured by means of laser Doppler flowmetry in 10 patients undergoing a PAO for symptomatic acetabular dysplasia. During the surgical procedure, the intraosseous high energy laser Doppler reliably depicts dynamic changes of small vessel blood flow. Measurements were performed after defined surgical steps to obtain sequential information on the blood perfusion of the acetabular fragment. RESULTS: After complete separation of the acetabular fragment, nine out of 10 patients had pulsatile signals, but the blood flow (BF) significantly decreased by 77%. Corrective positioning of the fragment induced no further drop of the BF signal but a loss of pulsatility in six patients. After a recovery period of about 30 min following preliminary fixation of the fragment, reestablishment of the pulsatile signal and an increase of the BF signal was seen. At termination of the surgical procedure, five out of eight patients, who could be followed throughout the whole procedure, showed a clear pulsatile signal in the supraacetabular area. Bleeding of the supraacetabular cancellous surface could be observed in all acetabula. CONCLUSION: Despite careful preservation of soft tissues during the surgical procedure, a significant reduction of the blood flow in the supraacetabular region has been observed. Nevertheless, a pulsatile signal in more than 60% of the fragments after fragment correction and an increasing signal during the recovery period showed ongoing blood perfusion indicating reversible changes in the measured supraacetabular area. All osteotomies healed within eight weeks without showing signs of necrosis during a minimum follow up of 1 year. 相似文献
3.
In 112 comatose patients somatosensory, visual and auditory evoked potentials were registered within 36 hours after the onset of coma or admission. Main causes of coma were head injury, and intracerebral and subarachnoid haemorrhage. The initial bilateral loss of any evoked potential was associated with a mortality of 98%. Normal somatosensory evoked potentials were associated with a survival rate of 74%, while normal visual and normal auditory evoked potentials had a survival rate of 60% and 66%, respectively. It is concluded that SEPs can be valuable for the prognosis of coma after primary brain lesions. 相似文献
4.
5.
J Goldhahn M Reinhold M Stauber C Knop R Frei E Schneider B Linke 《Journal of orthopaedic research》2006,24(5):917-925
The goal of our study was to evaluate two newly developed implant designs and their behavior in terms of subsidence in lumbar vertebral bodies under cyclic loading. The new implants were evaluated in two different configurations (two small prototypes vs. one large prototype with similar load-bearing area) in comparison to a conventional screw-based implant (MACS TL). A pool of 13 spines with a total of 65 vertebrae was used to establish five testing groups of similar bone mineral density (BMD) distribution with eight lumbar vertebrae each. In additional to BMD assessment via dual-energy X-ray absorptiometry, cancellous BMD and structural parameters were determined using a new generation in vivo 3D-pQCT. The specimens were loaded sinusoidally in force control at 1 Hz for 1000 cycles at three load levels (100, 200, and 400 N). A survival analysis using the number of cycles until failure (Cox regression with covariates) was applied to reveal differences between implant groups. All new prototype configurations except the large cylinder survived significantly longer than the control group. The number of cycles until failure was significantly correlated with the structural parameter Tb.Sp. and similarly with the cancellous BMD for three of five implants. In both large prototypes the cycle number until failure significantly correlated with the preoperative distance to the upper endplates. Although the direct relationship between bone structure or density and mechanical breakage behavior cannot be conclusively proven, all the prototypes adapted for poor bone structure performed better than the comparable conventional implant. 相似文献
6.
Klebsiella serotype K7 is found among the capsule types that are most prevalent in respiratory tract isolates. To evaluate the significance of the K7 antigen in bacteria-leucocyte interactions, K7-encapsulated Klebsiella pneumoniae strains and their non-capsulate mutants were investigated. The K7 isolates were compared to K2-capsulate strains and their respective K- derivatives. K7-capsulate bacteria were less hydrophilic, and more readily phagocytosed and killed by human polymorphonuclear leucocytes (PMNL) than K2 strains. Loss of the K7 antigen resulted in increased surface hydrophobicity but did not affect phagocytosis and killing, whereas loss of the K2 capsule caused greater susceptibility to the phagocytic and killing action of PMNL. Both the K7 and K2 antigen stimulated the extracellular release of lysozyme from neutrophils but not of myeloperoxidase, indicating degranulation of only secondary granules. All K- mutants induced the release of both lysozyme and myeloperoxidase. Our results suggest that, in contrast to the K2 antigen, the K7 capsular polysaccharide does not confer antiphagocytic properties on bacteria. However, the K7 antigen is able to impede the extracellular release of primary granule enzymes. 相似文献
7.
G C van Rhoon J van der Zee M P Broekmeyer-Reurink A G Visser H S Reinhold 《International journal of hyperthermia》1992,8(6):843-854
The capacity of a radiofrequency, 13.56 MHz, capacitive hyperthermia system using extensive pre-cooling of the subcutaneous tissue to induce locoregional deep heating has been investigated in 11 patients. Tumour location was presacral in nine--and eccentric towards the lateral side of the pelvis in two patients. For thermometry multiple catheters (mean 2.7) were inserted into the treatment volume. The mean numbers of temperature measuring points per treatment were 9.4 in tumour, 5.5 in muscle and 7.2 in subcutaneous fat. RF energy was applied after 30 min of cooling through two flexible boli perfused with saline water at 5-10 degrees C. Patient tolerance to pre-cooling was very good and after some initial discomfort the patient became rapidly accustomed to the cold water boli. For some patients better temperatures were achieved when the conventional anterior-posterior applicator set-up was replaced by a set-up with an applicator on each lateral side of the patient. As patients can tolerate temperatures within the fat tissue as high as 45.5 degrees C without complaining it appears important to monitor the temperature at the transition of fat to muscle tissue to prevent subcutaneous burns. The study shows that pre-cooling cannot avoid preferential heating at the interface from fat to muscle tissue. In this patient group the quality of the hyperthermia treatment appeared to be rather poor: 60% of the measured tumour temperatures were below 40 degrees D. 相似文献
8.
Martin Zeier Jolanta Perz Reinhold P Linke Ugo Donini Rüdiger Waldherr Konrad Andrassy Anthony D Ho Hartmut Goldschmidt 《Nephrology, dialysis, transplantation》2003,18(12):2644-2647
BACKGROUND: High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown. METHODS: In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow. RESULTS: In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy. CONCLUSION: Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress. 相似文献
9.
G Reinhold 《Zeitschrift für die gesamte Hygiene und ihre Grenzgebiete》1989,35(7):432-433
In general the anaerobic digestion leads to a reduction of the pathogenic microorganisms in the fermented substrat. The level of the reduction is determined by the reaction temperature and by the hydraulic retention time of the slurry in the digester. In 1986 investigations were carried out in the agricultural biogas plant in Vippachedelhausen. The main results are: The decrease of microorganisms during the agricultural biogasproduction is not so strength as described by other authors. A reduction of about one order of magnitude was measured. In the case of 10(7) to 10(9) microorganisms inside the start slurry the reduction is only of a small practical importance. This small reduction is caused by the short hydraulic retention time of about 12 days in connection with the principle of the stirred tank reaktor. 相似文献
10.
Many techniques of magnetic resonance angiography depend on flow velocity. The broad normal range of venous flow velocities and preferential patterns of drainage, particularly in the transverse sinuses, may produce images that are diagnostically misleading. This reports such a case, with samples of various flow patterns in the transverse sinuses of other individuals, as demonstrated by one magnetic resonance angiographic technique (time-of-flight). 相似文献