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101.
102.
Mary S. Davey J. M. Zerin Clarence Reilly Walter T. Ambrosius 《Pediatric radiology》1997,27(12):908-911
Objective. To determine if mild renal pelvic dilatation at renal ultrasound (RUS) is a reliable sign of vesicoureteral reflux (VUR)
at voiding cystourethrogram (VCUG) in children. Materials and methods. All patients less than 10 years of age who had RUS and VCUG on the same day during a 2-year period were identified in a computerized
database. The appearance of the collecting system of each kidney was classified into two groups: group 0 – no dilatation (≤
2-mm anteroposterior diameter of the renal pelvis) and group 1 – 3 to 10-mm AP diameter of the renal pelvis without caliectasis.
VUR at VCUG was graded using the International Reflux Study Committee system. Results. Four hundred fifty-five patients (76 boys; 379 girls) with 910 kidneys were included. VUR occurred in 268 kidneys in 174
patients. There were 820 group 0 kidneys and 90 group 1 kidneys. Kidneys classified as group 1 (25.0 % had reflux) were no
more likely to have reflux than were kidneys with nondistended (group 0) collecting systems (31.2 % had reflux). There was
no statistical difference in the rate of reflux in patients with group 1 renal pelvic distention (39.2 % refluxed) and a normal
collecting system (33.3 % refluxed) (P = 0.365). Conclusion. The frequency of vesicoureteral reflux in children with mild renal pelvic distention is not significantly different than
in children with no distention. Therefore, mild dilatation of the renal pelvis should not be considered an indication for
voiding cystourethrography.
Received: 14 April 1997 Accepted: 24 July 1997 相似文献
103.
Social work, general practice and evidence-based policy in the collaborative care of older people: current problems and future possibilities 总被引:1,自引:0,他引:1
Kalpa Kharicha BA MHSc Enid Levin BA Dip Soc Ant Steve Iliffe BSc MRCGP Barbara Davey BSc MSc 《Health & social care in the community》2004,12(2):134-141
While collaborative (or joint) working between social services and primary healthcare continues to rise up the policy agenda, current policy is not based on sound evidence of benefit to either patients or the wider community. Both sets of practitioners report benefits for their own work from adopting new arrangements for collaboration. The underlying assumption behind much of this activity is that a greater degree of integration provides benefits to both users and their carers, a perspective that at times obscures the issue of resource availability, especially in the form of practical community services such as district nursing and home help. At the present time there is insufficient evidence to demonstrate that formal arrangements for collaborative working (CW) are better than those forged informally between committed individuals or teams. Furthermore, arrangements for CW have not hitherto been widely evaluated in systematic studies with a comparative design and focus on outcomes for users and carers rather than on processes. In this paper we propose a number of process measures for future evaluation of CW: (1) study populations must be comparable; (2) details of how services are actually delivered must be obtained and colocation should not be assumed to mean collaboration; (3) care packages in areas of comparable resources should be examined; (4) both destinational outcomes and user‐defined evaluations of benefit should be considered; (5) possible disadvantages of integrated care also need to be actively considered; (6) evaluations should include an economic analysis. Those implementing new policies in Primary Care Trusts have, at present, little sound evidence to guide them in their innovative work. However, they should take the opportunity to rigorously test the advantages and disadvantages of collaboration. 相似文献
104.
105.
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107.
Alcohol, ALDH2, and esophageal cancer: a meta-analysis which illustrates the potentials and limitations of a Mendelian randomization approach. 总被引:2,自引:0,他引:2
Mendelian randomization, the use of common polymorphisms as surrogates for measuring exposure levels in epidemiologic studies, provides one method of assessing the causal nature of some environmental exposures. This can be illustrated by looking at the association between the ALDH2 polymorphism and esophageal cancer. Alcohol drinking is considered a risk factor for esophageal cancer, and exposure to high levels of acetaldehyde, the principal metabolite of alcohol, may be responsible for the increased cancer risk. The ability to metabolize acetaldehyde is encoded by the ALDH2 gene, which is polymorphic in some populations. The ALDH2*2 allele produces an inactive protein subunit, which is unable to metabolize acetaldehyde. An individual's genotype at this locus may influence their esophageal cancer risk through two mechanisms, first through influencing alcohol intake and second through influencing acetaldehyde levels. We have carried out a meta-analysis of studies looking at the ALDH2 genotype and esophageal cancer and found that risk was reduced among *2*2 homozygotes [odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.16-0.80] and increased among heterozygotes (OR, 3.19; 95% CI, 1.86-5.47) relative to *1*1 homozygotes. This provides strong evidence that alcohol intake increases the risk of esophageal cancer and individuals whose genotype results in markedly lower intake, because they have an adverse reaction to alcohol are thus protected. This meta-analysis also provides evidence that acetaldehyde plays a carcinogenic role in esophageal cancer. The two different processes operating as a result of the ALDH2 genotype have implications for the interpretation of studies using the Mendelian randomization paradigm. 相似文献
108.
109.
Using fMRI to quantify the time dependence of remifentanil analgesia in the human brain. 总被引:3,自引:0,他引:3
To understand and exploit centrally acting drugs requires reliable measures of their time course of action in the human brain. Functional magnetic resonance imaging (fMRI) is able to measure noninvasively, drug-induced changes in task-related brain activity. Here, we have characterized, in a specific region of the brain, the time of onset of action and the half-life of action of a clinically relevant dose of a potent opioid analgesic agent, remifentanil. These times were established from the temporal variation of the amplitude of the blood oxygen level-dependent response in the insular cortex contralateral to a painfully hot thermal stimulus, in volunteers receiving a remifentanil infusion. The insular cortex has repeatedly been reported as activated by noxious thermal stimulation. The times of onset and offset of drug action were each characterized by a half-life for changes in fMRI signal from within the insula. These characteristic times agreed with the observed drug-induced analgesia and previous pharmacokinetic-pharmacodynamic measurements for remifentanil. We have successfully measured, for the first time using fMRI, temporal pharmacological parameters for a CNS-active drug based on its effect on task-related activity in a specific brain region. Comparison of the time course of regional brain activity with pain perception could reveal those regions engaged in drug-induced analgesia. 相似文献
110.
George Davey Smith 《British medical journal》2004,329(7480):1424-1425