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排序方式: 共有561条查询结果,搜索用时 234 毫秒
1.
2.
T. Scholz Ø. Mathisen A. Bergan S. Osnes R. Innes T. Pedersen A. O. Aasen O. Søreide 《Transplant international》1997,10(3):180-184
We have introduced and evaluated several modifications of the conventional venovenous bypass (VVBP) in 29 adult patients
undergoing liver transplantation (OLT). A percutaneous technique for insertion of a jugular venous return cannula and a femoral
vein cannula was applied. The inferior mesenteric vein (IMV) was used for splanchnic decompression, which facilitated dissection
of the recipient liver and allowed portal anastomosis to be performed without disconnecting the portal bypass. A heat exchanger
was introduced into the bypass circuit to prevent heat loss. The percutaneous technique prevented complications related to
dissection in the axilla and groin. Hemodynamic characteristics corresponded to those found using the traditional technique.
Complications related to the VVBP were seen in only one patient in whom the femoral catheter was accidentally introduced into
the femoral artery. We conclude that percutaneous cannulas, use of the IMV for splanchnic decompression and the introduction
of a heat exchanger offer significant benefits and that they are safe and reliable.
Received: 23 August 1996 Received after revision: 14 January 1997 Accepted: 27 January 1997 相似文献
3.
Objective: The scientific quality of research is an important ethical issue. To clarify the quality of research projects in pharmacotherapy/pharmacology,
40 randomly selected research projects in pharmacotherapy/pharmacology submitted to a research ethics committee were reviewed.
Results: Eight of the projects would not have contributed new knowledge nor were they necessary as controls for the results of previous
research. Fifteen of the research protocols were of good quality, 15 could be used after revisions, and 10 were unfit for
use. Eleven of the research projects were not finished 5 years after they were started. A written report was produced from
26 of the projects. Nine were of good quality and could be accepted for publication in a medical journal, 10 of the reports
were in need of revision before publication, and 7 should not be accepted for publication.
Conclusion: Research in this field ought to be improved, and ways to improve the standard of clinical trials in pharmacotherapy are
dicussed.
Received: 1 April 1996 / Accepted in revised form: 28 June 1996 相似文献
4.
Berenice Mathisen Sheena Reilly David Skuse 《Developmental medicine and child neurology》1992,34(2):141-149
The oral-motor function of 10 infants with Turner syndrome and their age- and sex-matched controls were assessed during feeding. In addition to well-recognised dysmorphic features, including oral anomalies and high-arched palates, index infants had marked hypotonia of the cheeks and lips, dysfunctional tongue movements and poorly developed chewing skills. Their meal-times were significantly shorter than those of the controls and they weighed significantly less at six, 12 and 15 months. All mothers of infants with Turner syndrome complained of difficulties feeding their children and these problems often had been present since birth. 相似文献
5.
Eighty patients with inflammatory stenoses of the subglottic larynx and upper trachea were treated by single-stage laryngotracheal resection and reconstruction. Fifty stenoses originated from postintubation lesions (endotracheal tubes, tracheostomy, cricothyroidostomy), 7 originated from trauma, 19 were idiopathic, and 4 were miscellaneous. Repair consisted of resection of the anterolateral cricoid arch in all patients, plus resection of posterior laryngeal stenosis where present, with salvage of the posterior cricoid plate, appropriate resection and tailoring of the trachea, and primary anastomosis using a posterior membranous tracheal wall flap to resurface the bared cricoid cartilage in 31 patients. One postoperative death resulted from acute myocardial infarction. Long-term results were excellent in 18 patients, good in 48, satisfactory in 8, and failure in 2. Three additional patients had good results at discharge but were followed up for less than 6 months. 相似文献
6.
Ø. G. Martinsen S. Grimnes E. S. Kongshaug 《Medical & biological engineering & computing》1997,35(3):177-180
Some electrical properties of human hair have been investigated to determine whether a significant DC electrical conductance
is present in keratinised tissues. The DC conductance was found to be substantial and highly dependent on the moisture level
in the hair fibres. At high moisture levels, the conductance was found to be almost frequency independent below 1 kHz. Absorption
and desorption profiles were also monitored, revealing different stages of sorption mechanisms in the fibres. Although absorption
was found to be a slow process with ‘time constants’ in the range of hours, desorption was much faster, in the range of a
few minutes. 相似文献
7.
Thyroid hormone induction of keratin genes: a two-step activation of gene expression during development 总被引:7,自引:0,他引:7
To determine the mechanism of action of the thyroid hormone triiodothyronine (T3) during metamorphosis of the amphibian epidermis, we have investigated the developmental activation of the 63-kD keratin genes in the frog Xenopus laevis. These genes code for three closely related keratins that first appear in the larval epidermis and accumulate during metamorphosis to become the most abundant proteins in the adult epidermis. We report here that the 63-kD keratins and their mRNAs first appear at stages 48-52. The level of 63-kD keratin gene expression remains relatively low until stage 56 and then increases dramatically. Quantitative analysis of the concentration of 63-kD keratin mRNA demonstrates low levels until stage 55/56, followed by an increase greater than 300-fold from stage 55/56 to the adult. Each adult cell contains approximately 55,000 molecules of the 63-kD keratin mRNAs. T3 is not required for the initial activation of the 63-kD keratin genes, but high-level expression is absolutely dependent on T3. High-level expression is prevented by propylthiouracil, which inhibits thyroid hormone synthesis and can be induced precociously both in vivo and in vitro with exogenous T3 as early as stage 48, but not prior to that time. Thus, the full activation of the 63-kD keratin genes during development requires two regulatory steps, one independent and one dependent on T3. 相似文献
8.
Summary The prevalence of virus-specific serum antibodies of IgA class against cytomegalovirus (CMV) was determined in 228 healthy blood donors and in 112 patients suspected of CMV infection. All patients had a titer of 40 or higher in the complement fixation test. Specific CMV-IgA was found in 81 per cent of CMV-IgM positive patient sera and in 20 per cent of sera from patients strongly suspected of CMV infection, but with negative CMV-IgM. Less than 2 per cent of healthy blood donors had CMV specific serum IgA.With 4 Figures 相似文献
9.
N. Ø. Christensen R. Nydal F. Frandsen S. B. Sirag P. Nansen 《Parasitology research》1981,65(3):293-298
Schistosoma sp. induced cross-resistance to a challenge withFasciola hepatica andEchinostoma revolutum was studied in mice. Primary patent 56-days-oldS. intercalatum andS. bovis infections stimulated a statistically significant level of resistance to a challenge withF. hepatica, and primary patent 100-day-oldS. bovis infections induced an almost complete resistance to a challenge withE. revolutum. Primary single-sexS. mansoni infections, either male or female, aged 90 days did not stimulate any resistance to a challenge withE. revolutum.A primary infection withS. mansoni aged 70 days induced a marked reduction (94.1–100%) in theE. revolutum worm recovery already 2 h post-challenge as compared with that of theE. revolutum challenge control group and complete elimination of the echinostome worm population inS. mansoni infected mice had taken place 24 h after challenge.
E. revolutum worm populations established in mice harbouring newly patent 36-day-oldS. mansoni infections persisted unchanged for a period of at least 33 days into the patent period of the schistosome infection in spite of development of a complete resistance to a challenge withE. revolutum metacercariae during this period. 相似文献
10.
Therese Fostervold Mathisen PhD Jorunn Sundgot-Borgen PhD Cynthia M. Bulik PhD Solfrid Bratland-Sanda PhD 《The International journal of eating disorders》2021,54(10):1766-1770
Accumulating evidence suggests that supervised and adapted physical activity provides cognitive benefits for individuals with eating disorders (EDs). The mechanisms underlying the benefits of physical activity are poorly understood. Addressing this knowledge gap may inform the appropriate integration of structured physical activity into eating disorders treatment and recovery. We draw attention to recent findings in the study of the impact of physical activity on the brain, and we describe the neurostructural and neurocognitive changes associated with physical activity observed in various clinical and nonclinical populations. Considering the identified impairment in brain volume- and/or neurocognitive function in various EDs, we propose that positive effects of physical activity may play a meaningful role in successful ED treatment. Accordingly, we outline research steps for closing the knowledge gap on how physical activity may aid in ED recovery, and emphasize the need to combine measures of cognitive and behavioral responses to physical activity, with technology capable of measuring changes in brain structure and/or function. 相似文献