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排序方式: 共有807条查询结果,搜索用时 15 毫秒
101.
Francesco Rosato Dario Bruzzone Faisal H. Cheema Antonio Capo Enrico Ardemagni Anna Verna Silvia Rosano Claudio Grossi Fabio Barili 《Artificial organs》2012,36(10):868-874
The comparison of hemodilution at the end of surgery is of limited use as it represents only a snapshot of a dynamic phenomenon. This study was undertaken to compare the perioperative hemoglobin curves of isolated coronary artery bypass grafting performed with minimized extracorporeal circulation, traditional cardiopulmonary bypass, and off‐pump technique. The propensity score method was used to select three groups of patients, homogenous regarding preoperative and operative data, who underwent isolated coronary artery bypass grafting. A generalized linear mixed model was used for estimating differences in perioperative hemoglobin trends among groups. The three groups were each composed of 50 patients with no differences in demographic data, preoperative risk profile, preoperative hemoglobin, or type of surgery. There was no significant difference in major postoperative complications. The pattern of the hemodilution curves was similar in patients operated with mini‐circuit and off‐pump technique (P > 005). Mini‐circuit led to a 3.1 ± 11.9% hemoglobin reduction, which was similar to the off‐pump group (1.6 ± 8.9%, P = 0.99 at ANOVA) and significantly different from the standard extracorporeal circuit group (16.0 ± 10.3%, P < 0.001 at ANOVA). The generalized linear mixed model determined that the standard circuit was the only independent predictor for increased hemodilution. Its effect on hemodilution was time‐dependent and the slope of the hemoglobin curve was more pronounced between systemic heparinization and the end of surgery. Perioperative hemoglobin trends of patients who underwent myocardial revascularization with mini‐circuit were similar to those of off‐pump surgery and significantly less pronounced than those of standard extracorporeal circulation. 相似文献
102.
Percutaneous transjejunal approaches to the biliary system 总被引:2,自引:0,他引:2
103.
104.
De Klein A; Riegman PH; Bijlsma EK; Heldoorn A; Muijtjens M; den Bakker MA; Avezaat CJ; Zwarthoff EC 《Human molecular genetics》1998,7(3):393-398
We describe a G-->A transition within intron 5 of the NF2 gene. This
mutation creates a consensus splice branch point sequence. To our knowledge
this is the first report of a mutation that creates a functional branch
point sequence in a human hereditary disorder. The new branch point
sequence is located 18 bp upstream of a consensus splice acceptor site. A
consensus splice donor site is found 106 bp 3' of the acceptor site. Asa
consequence the G-->A transition results in an alternatively spliced
mRNA containing an additional exon 5a of 106 bp derived from intron
sequences. We cloned the mutant cDNA and show that due to an in-frame stop
codon the cDNA codes for a truncated NF2 protein. The mutation was observed
in three affected members of an NF2 family. In a tumour of one of the
family members both alternatively spliced and wild-type mRNA were found,
although the wild-type allele of the gene is absent due to an interstitial
deletion on chromosome 22. We also show that immunoprecipitations reveal
the presence of full-length wild-type NF2 protein in the tumour lysate.
These data support the hypothesis that some degree of normal splicing of
the mutant precursor RNA is taking place. It is therefore likely that this
residual activity of the mutant allele explains the relatively mild
phenotype in the family. These data also indicate that complete
inactivation of the gene is not required for tumour formation.
相似文献
105.
Thurman EC; Walker J; Jayaraman S; Manjunath N; Ardman B; Green JM 《International immunology》1998,10(5):691-701
Accessory molecule interactions can be critical in determining the outcome
of a T cell's encounter with antigen. Cell adhesion proteins may augment T
cell responses by facilitating TCR engagement of the antigen-MHC complex,
while co-stimulatory molecules may deliver distinct signals that modulate T
cell responsiveness. CD43 (leukosialin, sialophorin) has been suggested to
influence cell activation by steric hindrance based upon the large size and
glycosylation of the protein, as well as the relative abundance of the
protein on the cell surface. In this paper we examine both in vitro and in
vivo T cell-dependent responses in CD43-deficient mice. We demonstrate that
T cells from CD43-deficient mice are hyper-responsive following both in
vivo and in vitro activation, and that this is observed in response to not
only TCR-CD3-mediated stimulation, but also following receptor-independent
activation. This data suggests that mechanisms other than non-specific
steric hindrance are important in the regulation of T cell activation by
CD43.
相似文献
106.
107.
Rabbit carotid bodies were frozen in situ to destroy type I cells. After a one-year period of recovery allowing the sensory nerve fibres to regenerate, the animals were reexamined. Results showed that type I cells were not all destroyed in many instances but also that the presence of ventilatory reactions to chemoreceptor stimuli was always related to the presence of type I cells. 相似文献
108.
Emergency room radiography of asthma: an efficacy study 总被引:2,自引:0,他引:2
109.
Two cases of left atrial myxoma were evaluated with magnetic resonance (MR) imaging. In both cases, the myxoma was clearly defined as to its location, origin, and size. In one case, the myxoma prolapsed through the mitral valve. Our study indicates that MR imaging is valuable in the diagnosis of myxomas. 相似文献
110.
Verna Hildebrand 《Early child development and care》1988,37(1):55-64
Children as they are born into the world are a bundle of human potential. This potential must be nurtured and educated if these children are to make a contribution to the world society. Third World children hold the same promise as other children if they are born to healthy mothers. Societies must contribute both physical resources and human resources for this promise to be fulfilled.
Many Third World children need immunizations, better nutrition, oral rehydration therapy, and educational opportunities if they are to survive and reach their potential.
A proposal is made for international development agencies to help fund child care centers which could become a focus of many services for both the children and their families. 相似文献
Many Third World children need immunizations, better nutrition, oral rehydration therapy, and educational opportunities if they are to survive and reach their potential.
A proposal is made for international development agencies to help fund child care centers which could become a focus of many services for both the children and their families. 相似文献