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排序方式: 共有534条查询结果,搜索用时 0 毫秒
531.
Maegele M Lefering R Yucel N Tjardes T Rixen D Paffrath T Simanski C Neugebauer E Bouillon B;AG Polytrauma of the German Trauma Society 《Injury》2007,38(3):298-304
BACKGROUND: There is increasing evidence for acute traumatic coagulopathy occurring prior to emergency room (ER) admission but detailed information is lacking. PATIENTS AND METHODS: A retrospective analysis using the German Trauma Registry database including 17,200 multiple injured patients was conducted to determine (a) to what extent clinically relevant coagulopathy has already been established upon ER admission, and whether its presence was associated (b) with the amount of intravenous fluids (i.v.) administered pre-clinically, (c) with the magnitude of injury, and (d) with impaired outcome and mortality. Eight thousand seven hundred and twenty-four patients with complete data sets were screened. RESULTS: Coagulopathy upon ER admission as defined by prothrombin time test (Quick's value) <70% and/or platelets <100,000 microl(-1), was present in 34.2% of all patients. There was an increasing incidence for coagulopathy with increasing amounts of i.v. fluids administered pre-clinically. Coagulopathy was observed in >40% of patients with >2000 ml, in >50% with >3000 ml, and in >70% with >4000 ml administered. Ten percentage of patients presented with clotting disorders although pre-clinical resuscitation was limited to 500 ml of i.v. fluids maximum. The mean ISS score in the coagulopathy group was 30 (S.D. 15) versus 21 (S.D. 12) (p<0.001). Twenty-nine percentage of patients with coagulopathy developed multi organ failure (p<0.001). Early in-hospital mortality (<24h) was 13% in patients with coagulopathy (p<0.001) and overall in-hospital mortality totalled 28% (p<0.001). CONCLUSION: There is a high frequency of established coagulopathy in multiple injury upon ER admission. The presence of early traumatic coagulopathy was associated with the amount of intravenous fluids administered pre-clinically, magnitude of injury, and impaired outcome. 相似文献
532.
Embryo morphology or cleavage stage: how to select the best embryos for transfer after in-vitro fertilization 总被引:11,自引:15,他引:11
Ziebe S; Petersen K; Lindenberg S; Andersen AG; Gabrielsen A; Andersen AN 《Human reproduction (Oxford, England)》1997,12(7):1545-1549
This retrospective study of 1001 in-vitro fertilization (IVF) cycles
included a consecutive series of single transfers (n = 341), dual transfers
(n = 410) and triple transfers (n = 250) where all the transferred embryos
in each cycle were of identical quality score and identical cleavage stage.
In our 2 day culture system, transfer of 4- cell embryos resulted in a
significantly higher implantation rate and pregnancy rate (23 and 49%)
compared with 2-cell embryos (12 and 22%) and 3-cell embryos (7 and 15%).
Furthermore, the transfer of 4-cell embryos resulted in a significantly
higher pregnancy rate compared with embryos that had cleaved beyond the
4-cell stage (28%). The implantation rate (21%) and pregnancy rate (43%)
after transfer of embryos of score 1.0 were significantly higher than after
transfer of embryos of score 2.0 (14 and 32% respectively). Transferring
embryos of score 2.1 resulted in significantly higher implantation rates
(26%) and similar pregnancy rates compared with score 1.0. Transferring
embryos of score 2.2-3.0 resulted in a significantly lower implantation
rate (5%) and pregnancy rate (15%). A striking finding was that embryos of
quality score 2.0 had a significantly lower implantation rate compared with
embryos of quality score 1.0 and 2.1 and a significantly lower pregnancy
rate compared to embryos of quality score 1.0. We also found a lower
implantation rate and pregnancy rate when transferring 3-cell embryos.
These findings may indicate periods of increased sensitivity to damage
during the cell cycle. In conclusion, these results substantiate the idea
of the superiority of 4-cell embryos and demonstrate that minor amounts of
fragments in the embryo may not be of any importance. These findings may
call for a shift when weighing the two main morphological components
(quality score and cleavage stage) in the sense that reaching a 4-cell
cleavage stage even with the presence of a minor amount of fragments should
be preferred to a 2-cell embryo with no fragments.
相似文献
533.
The contribution of high linear energy transfer (L) charged particles to dosimetric and microdosimetric characteristics in a clinical proton beam was experimentally studied using an ionization chamber and track etched detectors. The particles mentioned are produced by proton nuclear interactions; at the Bragg peak region slowed down protons also contribute in the L region above several keV microm(-1). Due to these particles the biological weighted effective dose (BWED) of the beam changes with depth. The spectra of particles with L above 7 keV microm(-1) were established by means of track etched detectors, which permitted us to determine their contribution to dosimetric and microdosimetric characteristics of clinical proton beams. The studies were realized in the clinical proton beam of the JINR Dubna Phasotron, with a primary energy of 205 MeV. The relative contribution to the absorbed dose of the particles with L above 7 keV microm(-1) increases from several per cent at the beam entrance to several tens of per cent at the Bragg peak region. The relative biological weighted efficiency (RBWE) for radiotherapy has been calculated using a biological weighting function. It increases with depth from 1.02 at the beam entrance to about 1.25 at the Bragg peak region. 相似文献
534.
Bo AG Jönsson Lars Rylander Christian Lindh Anna Rignell-Hydbom Aleksander Giwercman Gunnar Toft Henning S Pedersen Jan K Ludwicki Katarzyna Góralczyk Valentyna Zvyezday Marcello Spanò Davide Bizzaro Eva C Bonefeld-Jörgensen Gian Carlo Manicardi Jens Peter Bonde Lars Hagmar 《Environmental health : a global access science source》2005,4(1):1-14