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11.

Background

Two decades of research has established the positive effect of using patient-targeted decision support interventions: patients gain knowledge, greater understanding of probabilities and increased confidence in decisions. Yet, despite their efficacy, the effectiveness of these decision support interventions in routine practice has yet to be established; widespread adoption has not occurred. The aim of this review was to search for and analyze the findings of published peer-reviewed studies that investigated the success levels of strategies or methods where attempts were made to implement patient-targeted decision support interventions into routine clinical settings.

Methods

An electronic search strategy was devised and adapted for the following databases: ASSIA, CINAHL, Embase, HMIC, Medline, Medline-in-process, OpenSIGLE, PsycINFO, Scopus, Social Services Abstracts, and the Web of Science. In addition, we used snowballing techniques. Studies were included after dual independent assessment.

Results

After assessment, 5322 abstracts yielded 51 articles for consideration. After examining full-texts, 17 studies were included and subjected to data extraction. The approach used in all studies was one where clinicians and their staff used a referral model, asking eligible patients to use decision support. The results point to significant challenges to the implementation of patient decision support using this model, including indifference on the part of health care professionals. This indifference stemmed from a reported lack of confidence in the content of decision support interventions and concern about disruption to established workflows, ultimately contributing to organizational inertia regarding their adoption.

Conclusions

It seems too early to make firm recommendations about how best to implement patient decision support into routine practice because approaches that use a ‘referral model’ consistently report difficulties. We sense that the underlying issues that militate against the use of patient decision support and, more generally, limit the adoption of shared decision making, are under-investigated and under-specified. Future reports from implementation studies could be improved by following guidelines, for example the SQUIRE proposals, and by adopting methods that would be able to go beyond the ‘barriers’ and ‘facilitators’ approach to understand more about the nature of professional and organizational resistance to these tools. The lack of incentives that reward the use of these interventions needs to be considered as a significant impediment.
  相似文献   
12.
Retinoblastoma is the most common primary intraocular malignancy in children, caused by inactivation of the RB1 gene on chromosome 13. We carried out a mutational screen of the exons and promoter of the RB1 gene in Indian patients with retinoblastoma in order to determine the range of mutations giving rise to disease. Forty-seven patients were screened for mutations in all exons and promoter of the RB1 gene by single strand conformation polymorphism followed by sequencing. Tumors were available from 27 patients (12 bilateral and 15 unilateral retinoblastoma) while only peripheral blood was available from 20 patients, all with bilateral disease. Mutations were found in 22 patients, 9 from the analysis of tumors and 13 from peripheral blood. Eight novel mutations were identified, including 4 single base changes, 2 small deletions and 1 duplication. These are g.64365T>G (Tyr325Ter), g.78131G>A (Trp515Ter), g.150061G>T (Glu587Ter), g.170383C>G (S834X), g.41924A>C (IVS3-2A>C), g.150064ins4, g.160792del22, and g.76940del14 (IVS15 del +20-33). Almost all mutations produced nonsense codons or frameshifts. Recurrent mutations, especially at CpG sites were seen predominantly. Detectable mutations in exons were found in 46% of patients tested. Large deletions, epigenetic changes as well as mutations in non-coding regions may be the cause of disease in the remainder of patients. Knowledge of the full range of mutations can aid in the design of screening tests for individuals at risk.  相似文献   
13.
Aim: To describe cardiorespiratory fitness and body mass index (BMI) values in a representative population of 9-year-old Norwegian children in two rural communities and compare present values with previous findings.
Methods: Two hundred and fifty-nine 9-year-old children were invited, and 256 participated in this study. Maximal oxygen uptake was directly measured during a continuous progressive treadmill protocol. Body mass and height were also measured.
Results: The mean ± SD relative maximal oxygen uptake was 52.8 ± 6.5 for boys and 46.9 ± 7.2 mL/kg/min for girls. Eight percent of the boys and 16.8% of the girls were classified as overweight, and 1.6% of the boys and 6.9% of the girls as obese. Mean age, body mass, height and Ponderal index were not significantly different between sexes. Girls had a higher BMI than boys (p = 0.05).
Conclusion: Compared to earlier Norwegian studies, children's BMI values seem to have increased substantially. This increase is most pronounced in girls. When assessing these differences using the PI, this increase is less marked. Comparing maximal oxygen uptake data with that in earlier Nordic studies, there is no evidence that fitness has declined among 9-year olds. However, the limitations of the few earlier studies make reliable comparisons difficult.  相似文献   
14.
PURPOSE: Pathogenesis of Acanthamoeba keratitis involves breakdown of epithelial barrier, stromal invasion by Acanthamoeba, loss of keratocytes, inflammatory response and finally stromal necrosis. The loss of keratocytes, believed to be due to the phagocytic activity of the parasite, occurs disproportionate to and independent of the parasite load, thereby suggesting additional modes of cell loss. To test our hypothesis that the loss of keratocytes in Acanthamoeba keratitis is due to apoptosis, we did both histology and histochemistry on the corneal tissues. METHODS: Routine Haematoxylin and Eosin, Gomori's Methenamine Silver and Periodic acid Schiff stained sections of five corneal tissues from penetrating keratoplasty and eviscerated eyes were reviewed. TUNEL staining was done for morphological detection of apoptosis in three cases, using formalin-fixed, paraffin-processed tissues. RESULTS: Histological changes were epithelial ulceration, loss of keratocytes in all layers, inflammation in anterior two-thirds of the stroma with necrosis, and deeper quiet stroma. Acanthamoeba trophozoites were found in the anterior stroma while the cysts were more in the deeper stroma, with minimal or no inflammatory response. TUNEL staining was positive in keratocytic nuclei in all layers. CONCLUSIONS: This study demonstrates that one of the modes of keratocyte loss in Acanthamoeba keratitis is by apoptosis, possibly in addition to the necrotic process and phagocytic activity of the parasite. The death of inflammatory cells also appears to be mediated by apoptosis.  相似文献   
15.
Conjunctival intraepithelial neoplasia presenting as corneal ulcer   总被引:2,自引:0,他引:2  
PURPOSE: To report a case of conjunctival intraepithelial neoplasia presenting as corneal ulcer. METHOD: Case report of a 28-year-old man who presented with sudden onset of pain, redness, and watering in the right eye. Examination of right cornea revealed deep stromal infiltrate inferonasally. Adjacent to the infiltrate and straddling the inferonasal limbus, a reddish well-defined sessible lesion with prominent blood vessels was seen. After corneal scraping for microbiological evaluation, the patient was treated with frequent instillation of ciprofloxacin hydrochloride 0.3% eyedrops. RESULTS: Corneal scraping revealed no microorganisms. Infiltrate resolved promptly after excision of the lesion. Histopathologic evaluation of the excised lesion revealed conjunctival intraepithelial neoplasia. CONCLUSIONS: This case highlights the fact that conjunctival intraepithelial neoplasia at the limbus may present as corneal ulcer. This ulcer could have occurred secondary to a dellen formation and epithelial breakdown predisposing to a corneal ulcer.  相似文献   
16.
Twenty-one probands, twelve with bilateral and nine with unilateral retinoblastoma, were screened for mutations in the RB1 gene using genomic DNA from peripheral blood leukocytes as well as tumors. Amplification of individual exons and flanking regions of the RB1 gene were carried out, followed by direct sequencing of the amplified products. Sequences of affected individuals were compared with those of controls. Mutations were identified in seven patients, five with bilateral and two with unilateral retinoblastoma. Six out of seven mutations involved the formation of premature termination codons by means of single base substitutions (2), frameshifts due to splice-site mutations (2), or deletion and duplication (2). One missense mutation was identified. Of the remaining fourteen patients, seven with bilateral disease had no mutations in peripheral blood (7 cases) or tumors (3/7 cases). Analysis of the peripheral blood of seven patients with unilateral disease also showed no mutations. Mutations were detected in about one-third of the cases, suggesting that hemizygous deletions at the RB1 locus or mutations outside the coding regions of RB1 may be responsible for the disease in the remaining patients.  相似文献   
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19.
OBJECT: Throughout the life of a mammal, new neurons are produced each day from resident progenitor cells located in the hippocampal dentate gyrus (DG). The availability of transgenic and knockout mice enables the evaluation of specific molecular mediators of this phenomenon. To facilitate such studies the authors characterized the proliferation, survival, and maturation of progenitor cells in the DG of adult mice following transient focal cerebral ischemia. METHODS: Anesthesia was induced in adult C57BL/6 mice by administering halothane. The middle cerebral artery (MCA) was then occluded for 120 minutes by applying an endovascular suture. The marker used to detect the presence of proliferating cells, 5-bromodeoxyuridine (BrdU; 50 mg/kg) was administered intraperitoneally twice daily on Days 2 through 6 after the MCA occlusion. Cohorts of mice were killed on Days 7 and 21, after which their brains were sectioned and BrdU-positive cells were detected using immunohistochemical analysis. The phenotype of the BrdU-positive cells was identified by fluorescent triple labeling by using antibodies specific for neuronal and astroglial markers together with anti-BrdU antibodies. The infarction was confirmed by applying cresyl violet staining. Compared with sham-operated control animals, there was a 4.6-fold (p < 0.05) increase in BrdU-positive cells in the ipsilateral DG at Day 7 postischemia. Twenty-one percent of the newly proliferated cells survived to Day 21 postischemia. At this time, the newly proliferated cells expressed the immature and mature neuron markers doublecortin and NeuN, respectively, but none expressed the astroglial marker glial fibrillary acidic protein. CONCLUSIONS: Focal ischemia induces neurogenesis in the DG of the mouse brain; this may be critical for postischemic brain repair.  相似文献   
20.
OBJECT: In previous studies at their laboratory the authors showed that cytidinediphosphocholine (CDP-choline), an intermediate of phosphatidylcholine synthesis, decreases edema formation and blood-brain barrier disruption following traumatic brain injury (TBI). In the present study the authors investigate whether CDP-choline protects hippocampal neurons after controlled cortical impact (CCI)-induced TBI in adult rats. METHODS: After adult male Sprague-Dawley rats had been anesthetized with halothane, a moderate-grade TBI was induced with the aid of a CCI device set at a velocity of 3 m/second, creating a 2-mm deformation. Sham-operated rats, which underwent craniectomy without impact served as controls. The CDP-choline (100, 200, and 400 mg/kg body weight) or saline was injected into the animals twice (once immediately postinjury and once 6 hours postinjury). Seven days after the injury, the rats were neurologically evaluated and killed, and the number of hippocampal neurons was estimated by examining thionine-stained brain sections. By 7 days postinjury, there was a significant amount of neuronal death in the ipsilateral hippocampus in the CA2 (by 53 +/- 7%, p < 0.05) and CA3 (by 59 +/- 9%, p < 0.05) regions and a contusion (volume 34 +/- 8 mm3) in the ipsilateral cortex compared with sham-operated control animals. Rats subjected to TBI also displayed severe neurological deficit at 7 days postinjury. Treating rats with CDP-choline (200 and 400 mg/kg, intraperitoneally) significantly prevented TBI-induced neuronal loss in the hippocampus, decreased cortical contusion volume, and improved neurological recovery. CONCLUSIONS: Treatment with CDP-choline decreased brain damage following TBI.  相似文献   
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