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排序方式: 共有2536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.
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
3.
4.
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
5.
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
6.
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
7.
Reinhold Kerbl 《Monatsschrift für Kinderheilkunde》2007,42(6):1012-1014
8.
Reinhold Kerbl 《P?diatrie und P?dologie》2007,42(6):8-9
Ohne Zusammenfassung 相似文献
9.
Swiatek M Greiner S Kemp S Drescher A Koop HU Herrmann RG Maier RM 《Current genetics》2003,43(1):45-53
The genetic transformation of plastids of higher plants has developed into a powerful approach for both basic research and biotechnology. Due to the high copy number of the plastid genome per plastid and per cell, repeated cycles of shoot regeneration under conditions selective for the modified plastid chromosome are required to obtain transformants entirely lacking wild-type plastid genomes. The presence of promiscuous plastid DNA in nuclear and/or mitochondrial genomes that generally contaminate even gradient-purified plastid fractions reduces the applicability of the highly sensitive PCR approach to monitor the absence of residual wild-type plastid chromosomes in transformed lines. It is therefore difficult, or even impossible, to assess reliably the hetero- or homoplastomic state of plastid transformants in this manner. By analysing wild-type and transplastomic mutants of tobacco, we demonstrate that separation of plastid chromosomes isolated from gradient-purified plastid fractions by pulsed-field gel electrophoresis can overcome the problem of (co)amplification of interfering promiscuous plastid DNA. PCR analyses with primers specific for plastid, mitochondrial and nuclear genes reveal an impressive purity of such plastid DNA fractions at a detection limit of less than one wild-type plastid chromosome copy per ten transplastomic cells. 相似文献
10.
Manfred Arnold Lutz Wohlfarth Willy Frank Günter Reinhold 《Macromolecular chemistry and physics.》1991,192(4):1017-1023
The influence of basic reaction parameters—the ratio of catalyst components, the composition of the monomer mixture and the temperature—on the progress of the copolymerization, the molecular weight and the molecular weight distribution as well as on the composition of the copolymers obtained is reported. Conversion data for the variation of the mole ratio of comonomers show a maximum for an [Al]/[V] mole ratio of approximately 7, whereas the molecular weight of copolymers is not significantly influenced. An increase in the molecular weight of the copolymers can be obtained by an increase of butadiene content in the monomer mixture. However, there is also an increasing incorporation of butadiene into the copolymer. Raising the temperature from ?60°C to 0°C results in a significant decrease in molecular weight, whereas the composition of the copolymers is not significantly changed. 相似文献