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排序方式: 共有2972条查询结果,搜索用时 15 毫秒
1.
Michiel R. de Boer Jos Twisk Annette C. Moll Hennie J. M. Völker-Dieben Henrica C. W. de Vet Ger H. M. B. van Rens 《Ophthalmic & physiological optics》2006,26(6):535-544
Consecutive patients (n = 215) who were referred to optometric (55%) or multidisciplinary (45%) low-vision services and above 50 years of age were recruited from four hospitals in the Netherlands. They completed two vision-related quality of life questionnaires, the Vision Quality of Life Core Measure (VCM1) and the Low Vision Quality of Life Questionnaire (LVQOL), before their first visit with low-vision services and 1 year later. At follow-up, patients referred to multidisciplinary low-vision services had lower scores on the mobility subscale of the LVQOL than patients referred to optometric low-vision services [5.3 points; 95% confidence interval (CI): 0.2-10.5]. Paired sample t-tests for the two groups of patients taken together show improvement for the VCM1 (3.1 points; 95% CI: 0.6-5.6) and deterioration for the basic aspects of vision (3.5 points; 95% CI: 1.1-5.9) and the mobility (6.6 points; 95% CI: 3.7-9.5) subscales of the LVQOL. In conclusion, people referred to optometric services showed less deterioration in mobility than those referred to multidisciplinary services. No differences were observed for any of the other subscales of the LVQOL and the VCM1. Future research in this field should include randomized controlled designs comparing low-vision services with no treatment or placebo. 相似文献
2.
HJ Aubin S Tilikete C Laureaux HT Nguyen Hac MC Roullet-Volmi S Troupel D Barrucand 《European psychiatry》1995,10(8)
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits. 相似文献
3.
Ruben Coronel Jacques M T de Bakker Francien J G Wilms-Schopman Tobias Opthof André C Linnenbank Charly N Belterman Michiel J Janse 《Heart rhythm》2006,3(9):1043-1050
BACKGROUND: Activation recovery intervals (ARIs) and monophasic action potential (MAP) duration are used as measures of action potential duration in beating hearts. However, controversies exist concerning the correct way to record MAPs or calculate ARIs. We have addressed these issues experimentally. OBJECTIVES: To experimentally address the controversies concerning the correct way to record MAPs or calculate ARIs. METHODS: Left ventricular local electrograms were recorded in isolated pig hearts with an exploring electrode grid, with a KCl reference electrode on the left ventricular myocardium, the aortic root, or the left atrium. Local activation was determined from calculated Laplacian electrograms. RESULTS: With the KCl electrode on the aortic root, local electrograms represented local activation. However, with the KCl electrode on the myocardium remote from the exploring electrode, a combined electrogram emerged consisting of local activation recorded from the grid and remote activation recorded from the reference electrode. The remote, inverted monophasic component did not show propagation and did not correlate with the Laplacian complex. When the KCl electrode was placed on the atrium during AV block, remote atrial monophasic components were completely dissociated from local, ventricular deflections. At left ventricular sites with a positive T wave, the Laplacian signal showed that the end of the T wave was caused by remote repolarization. During cooling-induced regional action potential prolongation, the T wave became negative, whereby the positive flank of the T wave remained correlated with repolarization (recorded with a MAP at the same site). CONCLUSIONS: MAPs are recorded from the depolarizing electrode. In both negative and positive T waves, the moment of maximum dV/dt corresponds to local repolarization. 相似文献
4.
5.
BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a
patient's vascular access would permit routine monitoring during
haemodialysis, and hence provide information of access graft deterioration
sufficiently early to increase the success of minimally invasive remedial
procedures. This paper reports the validation of such a method in animals.
METHODS: A PTFE graft was implanted in sheep between the carotid artery and
the jugular vein. While the sheep was under general anaesthesia and on an
haemodialysis circuit, ultrasound velocity in its blood was perturbed by
the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was
measured by a transit-time blood flow meter. This flow was combined with
the areas of perturbation generated by the injection before and after
mixing in the access flow to estimate graft flow. The calculated graft flow
was compared to flow measured directly by a transit-time probe on the same
carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow
measured by ultrasound velocity dilution agreed well with graft flow
measured directly with a scatter of 76 ml/min about the regression line.
CONCLUSION: Ultrasound velocity dilution provides a method for measuring
flow in the graft accurate enough for clinical evaluation of patients on
dialysis.
相似文献
6.
Nicole Y. L. Oei Bernet M. Elzinga Oliver T. Wolf Michiel B. de Ruiter Jessica S. Damoiseaux Joost P. A. Kuijer Dick J. Veltman Philip Scheltens Serge A. R. B. Rombouts 《Brain imaging and behavior》2007,1(1-2):31-41
Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized
to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects
of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized
placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion
of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design.
It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral
words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both
hippocampal and prefrontal brain regions that are crucially involved in memory processing.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
Michiel A. M. Feldberg M.D. Ph.D. Leon P. Driessen Theo D. Witkamp Maarten S. van Leeuwen Paul F. G. M. van Waes 《Urologic radiology》1988,10(1):92-94
In a case of diffuse xanthogranulomatous pyelonephritis, computed tomography (CT) and magnetic resonance (MR) were used. The MR proved to be more precise in the preoperative evaluation of inflammatory extension to the spleen and into the abdominal wall. The CT was more accurate in excluding spread to the colon. 相似文献
8.
M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
9.
Ossewaarde ME Bots ML van der Schouw YT de Kleijn MJ Wilmink HW Bak AA Planellas J Banga JD Grobbee DE 《Maturitas》2003,45(1):47-54
OBJECTIVES: To determine whether improvement in endothelial function of the brachial artery observed in women treated with hormone replacement therapy (HRT) may be explained by changes in lipid profile or blood pressure, information was used obtained in a single-centre, randomised, double blind, placebo-controlled trial. METHODS: Hundred-and-five healthy postmenopausal women, aged 50-65 years, were treated with 0.625 mg conjugated equine estrogens (CEE) combined with 2.5 mg medroxyprogesterone acetate (MPA) (CEE+MPA), 2.5 mg tibolone or placebo for 3 months. At baseline and after 3 months, endothelial function was assessed using flow-mediated dilatation (FMD) and nitro glycerine-mediated dilatation (NMD). Furthermore, lipids were measured. Multivariate linear regression analysis was applied to address the research question. RESULTS: Treatment with CEE+MPA resulted in an improvement in FMD of 2.0% (95% CI: -0.1; 4.1). CEE/MPA reduced total cholesterol with 13% (95% CI: -18%; -7%), LDL-cholesterol with 23% (95% CI: -30%; -15%) and lipoprotein(a) (Lp(a)) with 14% (95% CI: -26%; -2%). The magnitude of the relation of CEE/MPA with endothelial function was attenuated to from 2.0 to 1.6% when change in Lp(a) was taken into account. Adjustments for other lipids or blood pressure did not attenuate the association. CONCLUSIONS: The improvement in endothelial function in postmenopausal women treated with CEE+MPA appears to be partially mediated by change in Lp(a), and apparently not by changes in other lipids. 相似文献
10.
Functional defects in the fanconi anemia pathway in pancreatic cancer cells 总被引:17,自引:0,他引:17
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van der Heijden MS Brody JR Gallmeier E Cunningham SC Dezentje DA Shen D Hruban RH Kern SE 《The American journal of pathology》2004,165(2):651-657
Biallelic BRCA2-mutations can cause Fanconi anemia and are found in approximately 7% of pancreatic cancers. Recently, several sequence changes in FANCC and FANCG were reported in pancreatic cancer. Functional defects in the Fanconi pathway can result in a marked hypersensitivity to interstrand crosslinking agents, such as mitomycin C. The functional implications of mutations in the Fanconi pathway in cancer have not been fully studied yet; these studies are needed to pave the way for clinical trials of treatment with crosslinking agents of Fanconi-defective cancers. The competence of the proximal Fanconi pathway was screened in 21 pancreatic cancer cell lines by an assay of Fancd2 monoubiquitination using a Fancd2 immunoblot. The pancreatic cancer cell lines Hs766T and PL11 were defective in Fancd2 monoubiquitination. In PL11, this defect led to the identification of a large homozygous deletion in FANCC, the first cancer cell line found to be FANCC-null. The Fanconi-defective cell lines Hs766T, PL11, and CAPAN1 were hypersensitive to the crosslinking agent mitomycin C and some to cis-platin, as measured by cell survival assays and G(2)/M cell-cycle arrest. These results support the practical exploration of crosslinking agents for non-Fanconi anemia patients that have tumors defective in the Fanconi pathway. 相似文献