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121.
J Tiernan CD Briggs GRB Irving MT Swinscoe M Peterson IC Cameron 《Annals of the Royal College of Surgeons of England》2010,92(3):225-230
INTRODUCTION
In 2004, an audit in our unit demonstrated wide variation in liver resection rates for colorectal cancer (CRC) metastases within the cancer network. Subsequently, a network-wide CT-based follow-up and referral policy was introduced for all patients. A second audit was performed to assess the impact of the guidelines on liver resection rates.SUBJECTS AND METHODS
Analysis of prospective liver resection database between 1997 and 2004 and after the introduction of standardised guidelines between January 2005 and April 2008.RESULTS
A total of 362 patients underwent liver resection for CRC metastases between 1997 and 2008, 237 prior to the introduction of the referral guidelines and 125 after. Liver resection rates according to referring hospital varied from 0.92 to 2.32 per 100,000 population before guidelines were introduced. After 2005, resection rates from the four district hospitals standardised (1.68–1.84 per 100,000 population), but the central unit rate (Sheffield) remained significantly higher (2.67 per 100,000 population). No significant difference in 1-year disease-free survival between patients from Sheffield and the outlying hospitals was found (P = 0.553).CONCLUSIONS
Introduction of a referral protocol standardised resection rates from the four district hospitals, but these remain lower compared to the specialist centre. The wide-spread adoption of a policy to discuss all patients with liver metastases at an advanced disease multidisciplinary team meeting, in the presence of hepatobiliary specialists, may further increase resection rates across the UK. 相似文献122.
Robert E. Mann Mark Asbridge Gina Stoduto Reginald G. Smart David S. Goldbloom Evelyn R. Vingilis Christine M. Wickens 《Stress and health》2010,26(2):127-134
The current study examines the impact of psychological distress on the likelihood of reporting collision involvement in the preceding year. Two measures of psychological distress were obtained from the 12‐item General Health Questionnaire (GHQ‐12): depression–anxiety and social functioning. Data are based on the 2002–2004 Centre for Addiction and Mental Health Monitor (36 months), a repeated cross‐sectional telephone survey of Ontario adults aged 18 and older (n = 4935). Logistic regression analyses were performed on collision involvement within the past 12 months with the measures of depression–anxiety, social functioning and demographic factors as independent variables. The analyses revealed that the odds of involvement in a collision in the last 12 months were significantly related to the demographic factors of age, location of residence, income, educational level and marital status. After controlling for demographic factors, the odds of collision involvement increased significantly as the depression–anxiety score increased (odds ratio = 1.05 for each unit increase). These results suggest that higher levels of psychological distress, as indicated by scores on the depression–anxiety scale of the GHQ‐12, are associated with higher likelihood of collision involvement in the previous year. Research to understand the link observed here between distress and collision risk in the general population is needed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
123.
Wiegmann D McCarley JS Kramer AF Wickens CD 《Aviation, space, and environmental medicine》2006,77(8):825-831
INTRODUCTION: An experiment examined the impact of automation on young and old adults' abilities to detect threat objects in a simulated baggage-screening task. METHOD: Younger and older adult participants viewed X-ray images of cluttered baggage, 20% of which contained a hidden knife. Some participants were provided an automated aid with a hit rate of 0.90 and a false alarm rate of 0.25. The aid provided assistance to participants in one of three forms: a text message that appeared before the stimulus image; a text message that appeared following the stimulus image; or a spatial cue concurrent with the stimulus image. Control participants performed the task with no assistance from an aid. RESULTS: Spatial cuing improved performance for both age groups. Text cuing improved young adults' performance, but had no benefit for older participants. Effects were similar whether the text cue preceded or followed the search stimulus itself. DISCUSSION: Results indicate that spatial cuing rather than text alerts may be more effective in aiding performance during a baggage screening task and such benefits are likely to occur regardless of operator age. 相似文献
124.
Poor wettability of elastomeric impression materials results in surface defects on stone casts. This study examined the relationship between contact angles of die stone and voids in casts produced from five medium-viscosity impression materials. Contact angles of a die stone material formed against impression specimens made from polyether, addition and condensation silicones were measured by reflex microscope. The contact angle values achieved on the hydrophilic addition silicones were significantly higher than the polyether but lower than other silicone materials. Contact angle values correlated with the number of voids found at margins and line angles of stone casts but not with those on smooth surfaces. 相似文献
125.
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127.
Rabbits fed a vitamin E-deficient diet developed severe muscular dystrophy in 3-4 wk, but they did not become anemic. Nevertheless, reticulocyte counts increased in deficient rabbits (3.2%) compared to control rabbits (0.9%), and erythroid hyperplasia was evident in the bone marrow. Comparing deficient rabbits to controls, the plasma iron concentration was lower (134.4 versus 206.6 microgram/dl); the TIBC was higher (335.9 versus 228.3 microgram/dl); the whole blood protoporphyrin concentration was higher (131.6 versus 81.7 microgram/dl); and the total iron content was lower in spleen (71 versus 153 microgram), higher in skeletal muscle (4956 versus 3054 microgram), and unchanged in bone marrow, liver, and heart. Studies of iron absorption and excretion using 59Fe showed no abnormalities in deficient rabbits. There were abnormalities of ferrokinetics, however. The half-time of disappearance of 59Fe was shorter (100.6 versus 169.4 min), the plasma iron turnover was greater (1.25 versus 0.95 mg/dl blood/day), and the reappearance of 59Fe in circulating erythrocytes at day 9 was greater (77.2% versus 57.2%) in deficient rabbits. Anemia induced by phlebotomy accentuated the abnormal iron metabolism of deficient rabbits, and the animals were unable to correct the anemia. These findings show that vitamin E deficiency in rabbits causes abnormal erythropoiesis associated with abnormal iron metabolism and sequestration of iron in skeletal muscle. 相似文献
128.
Vaughan JR; Farrer MJ; Wszolek ZK; Gasser T; Durr A; Agid Y; Bonifati V; DeMichele G; Volpe G; Lincoln S; Breteler M; Meco G; Brice A; Marsden CD; Hardy J; Wood NW 《Human molecular genetics》1998,7(4):751-753
A mutation in exon 4 of the human alpha-synuclein gene was reported
recently in four families with autosomal dominant Parkinson's disease (PD).
In order to examine whether mutations in this exon or elsewhere in the gene
are common in familial PD, all seven exons of the alpha- synuclein gene
were amplified by PCR from index cases of 30 European and American
Caucasian kindreds affected with autosomal dominant PD. Each product was
sequenced directly and examined for mutations in the open reading frame. No
mutations were found in any of the samples examined. We conclude that the
A53T change described in the alpha- synuclein gene is a rare cause of PD or
may even be a rare variant. Mutations in the regulatory or intronic regions
of the gene were not excluded by this study.
相似文献
129.
mRNA stabilization by poly(A) binding protein is independent of poly(A) and requires translation 总被引:16,自引:0,他引:16
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Translation and mRNA stability are enhanced by the presence of a poly(A) tail. In vivo, the tail interacts with a conserved polypeptide, poly(A) binding protein (Pab1p). To examine Pab1p function in vivo, we have tethered Pab1p to the 3′ UTR of reporter mRNAs by fusing it to MS2 coat protein and placing MS2 binding sites in the 3′ UTR of the reporter. This strategy allows us to uncouple Pab1p function from its RNA binding activity. We show that mRNAs that lack a poly(A) tail in vivo are stabilized by Pab1p, and that the portions of Pab1p required for stabilization are genetically distinct from those required for poly(A) binding. In addition, stabilization by Pab1p requires ongoing translation of the mRNA. We conclude that the primary, or sole, function of poly(A) with respect to mRNA stability is simply to bring Pab1p to the mRNA, and that mRNA stabilization is an intrinsic property of Pab1p. The approach we describe may be useful in identifying and assaying 3′ UTR regulatory proteins, as it uncouples analysis of function from RNA binding. 相似文献
130.
The involvement of L-type calcium channels in heterosynaptic long-term depression (LTD) of the stratum radiatum input to area CA1 was studied in rat hippocampal slices. LTD of the radiatum field excitatory postsynaptic potential (EPSP) and population spike, produced by tetanization of the alveus in the presence of picrotoxin, was blocked by the calcium antagonist nimodipine and by a monoclonal antibody to the L-type calcium channel. LTD was produced in the absence of picrotoxin when the L-type calcium channel agonist, BAY-K8644, was applied. This effect was also blocked by nimodipine. These results indicate that L-type calcium channels are involved in heterosynaptic long-term depression. 相似文献