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ObjectiveClinical specialty societies recommend long-acting reversible contraceptives (LARCs) as first-line contraception for adolescent women. We evaluated whether a combined educational and process improvement intervention enhanced LARC placement in primary care within an integrated health care system.MethodsThe intervention included journal clubs, live continuing education, point-of-care guidelines, and new patient materials. We conducted a retrospective cohort study across 3 time periods: baseline (January 2013?September 2015), early implementation (October 2015–March 2016), and full implementation (April 2016–June 2017). The primary outcome was the proportion of LARCs placed by primary care clinicians among women aged 13 to 18 years compared with gynecology clinicians.ResultsKaiser Foundation Health Plan of Colorado cared for approximately 20,000 women aged 13 to 18 years in each calendar quarter between 2013 and 2017. Overall, LARC placement increased from 7.0 per 1000 members per quarter at baseline to 13.0 per 1000 during the full intervention. Primary care clinicians placed 6.2% of all LARCs in 2013, increasing to 32.1% by 2017 (P < .001), including 45.5% of contraceptive implants. Clinicians who attended educational sessions were more likely to adopt LARCs than those who did not (17.9% vs 6.4% respectively, P = .009). Neither overall LARC placement rates (relative risk, 1.9; 95% confidence interval, 0.7?5.6) nor contraceptive implant rates (relative risk, 3.0; 95% confidence interval, 0.9?9.8) increased significantly in clinicians who attended educational activities.ConclusionsThis multimodal intervention was associated with increased LARC placement for adolescent women in primary care. The combination of education and process improvement is a promising strategy to promote clinician behavior change.  相似文献   
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Ultrastructure of the early human implantation in vitro   总被引:1,自引:1,他引:1  
Four hatched human blastocysts obtained after in-vitro fertilizationand development were placed on monolayer cell cultures of humanendometrial epithelium, and subsequently examined by transmissionelectron microscopy. All four blastocysts became adherent tothe monolayer and three implanted and exhibited outgrowth oftheir trophoblastic cells. During implantation the blastocystsdifferentiated into mural and polar trophoblastic cells, andembryonic cells including endodermal cells. The endometrialcells were displaced and stacked into a multilayer at the peripheryof the implantation sites, allowing the trophoblastic cellsto come in contact with the culture dish. The endometrial cellsdisplayed local exo- or endo-cytosis where they contacted thetrophoblastic cells. The trophoblastic cells were not observedto be phagocytosing endometrial cells. These observations suggestthat human blastocysts portray an intrusive type of implantationduring the initial stages.  相似文献   
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Spinocerebellar ataxia 7 (SCA7) is an autosomal dominant neurodegenerative disorder caused by the expansion of a CAG-trinucleotide repeat in the coding region of the SCA7 gene. The expansion is translated into an extended polyglutamine stretch in the protein ataxin-7, a protein of unknown function. By Northern blot analysis expression of ataxin-7 was detected in numerous regions of human brain and some peripheral tissues. It is unknown, however, if ataxin-7 is enriched at sites of the SCA7 pathology. We studied the regional and cellular expression pattern of ataxin-7 at the mRNA level by in situ hybridization histochemistry in normal human brain. Furthermore we used a monoclonal and two polyclonal antibodies raised against the normal ataxin-7 to establish the distribution of this protein in brain, retina and peripheral organs. At the mRNA level ataxin-7 was preferentially expressed in neurons; the regional distribution reflected neuronal packing density. Ataxin-7 immunoreactivity (IR) was similarly widely expressed. In most neurons, ataxin-7 IR was preferentially localized to the cytoplasmatic compartment although some nuclear ataxin-7 IR was detected in most neurons. A more intense and more prominently nuclear ataxin-7 IR was observed in neurons of the pons and the inferior olive, brain regions severly affected by the disease, suggesting that the subcellular localization and abundance of ataxin-7 is regulated in a regionally specific way. Since neurons displaying more intense and more prominently nuclear ataxin-7 IR belonged to the class of susceptible cells in SCA7, an enrichment of normal ataxin-7 in the nuclear compartment may contribute to neurodegeneration. However not all sites of SCA7 pathology displayed a strong cytoplasmatic and nuclear immunoreactivity.  相似文献   
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Transgenic rat model of Huntington's disease   总被引:12,自引:0,他引:12  
Huntington's disease (HD) is a late manifesting neurodegenerative disorder in humans caused by an expansion of a CAG trinucleotide repeat of more than 39 units in a gene of unknown function. Several mouse models have been reported which show rapid progression of a phenotype leading to death within 3-5 months (transgenic models) resembling the rare juvenile course of HD (Westphal variant) or which do not present with any symptoms (knock-in mice). Owing to the small size of the brain, mice are not suitable for repetitive in vivo imaging studies. Also, rapid progression of the disease in the transgenic models limits their usefulness for neurotransplantation. We therefore generated a rat model transgenic of HD, which carries a truncated huntingtin cDNA fragment with 51 CAG repeats under control of the native rat huntingtin promoter. This is the first transgenic rat model of a neurodegenerative disorder of the brain. These rats exhibit adult-onset neurological phenotypes with reduced anxiety, cognitive impairments, and slowly progressive motor dysfunction as well as typical histopathological alterations in the form of neuronal nuclear inclusions in the brain. As in HD patients, in vivo imaging demonstrates striatal shrinkage in magnetic resonance images and a reduced brain glucose metabolism in high-resolution fluor-deoxy-glucose positron emission tomography studies. This model allows longitudinal in vivo imaging studies and is therefore ideally suited for the evaluation of novel therapeutic approaches such as neurotransplantation.  相似文献   
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Galectin-3 geh?rt zu einer Gruppe endogener Lektine mit Affinit?t zu beta-galaktosidhaltigen Glykokonjugaten (Galectin-1– 4 bzw. 1–7). Es ist in zahlreichen Geweben nachgewiesen und im Zusammenhang mit Tumorwachstum, Dedifferenzierung und Metastasierung untersucht worden. Nur wenige Untersuchungen besch?ftigten sich bislang mit dem Nachweis von Galectin-3 in Tumoren der Schilddrüse und mit der m?glichen differenzialdiagnostischen Bedeutung. Wir haben aus dem eigenen fortlaufenden operativen Untersuchungsgut insgesamt 118 Schilddrüsentumoren mit einem monoklonalen Antik?rper gegen Galectin-3 untersucht und die Pr?parate vergleichend unter Anwendung eines semiquantitativen Score zur Erfassung von Unterschieden der Expression ausgewertet. Normales Schilddrüsengewebe, nod?s-hyperplastisches Gewebe und Gewebe mit Funktionssteigerung sind für Galectin-3 weitgehend negativ. Adenome mit typischem zytologischem Befund sind überwiegend negativ, k?nnen aber herdf?rmig in Einzelzellen oder Follikelgruppen positiv reagieren. Papill?re Karzinome zeigen fast durchweg eine ausgepr?gte Galectin-3-Expression. Bei follikul?ren Karzinomen sowie oxyphilen Adenomen und Karzinomen sind die Befunde jedoch sehr uneinheitlich, und es finden sich neben positiven auch Galectin-3-negative Tumoren. Die follikul?re Variante des papill?ren Karzinoms ist mit der Galectin-3-Reaktion zuverl?ssig erfassbar. Die mit Galectin-3 erhobenen Befunde müssen jedoch bei der Beurteilung der Dignit?t von Tumorl?sionen der Schilddrüse u. E. mit kritischer Zurückhaltung und unter Einbeziehung bekannter histologischer Malignit?tskriterien bewertet werden.  相似文献   
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BackgroundAlthough over one hundred equations have been developed to predict the energy expenditure of individuals, none are sensitive to weight change in assessment of resting metabolic rate (RMR) before and after weight loss.ObjectiveTo formulate adjusted equations for overweight and obese individuals and to compare their accuracy with existing prediction RMR equations before and after weight loss.Subjects/materialsThis is historical prospective study. Participants included 39 overweight and obese men and women before and after losing 10–20% from baseline weight on a diet and physical activity regimen for at least three months. Pre and post weight loss measured RMR results were compared to estimated RMR using several existing prediction equations: Harris and Benedict, Ravussin and Bogardus, and Mifflin et al. To improve the accuracy of these prediction equations, we suggest new equations adjusted for weight loss, based on measured RMR and evaluated their accuracy.ResultsPre and post weight loss data indicated: significant fat reduction in both genders; reduction in free-fat mass only in men, and a significant decrease in measured RMR only in women. Our suggested equations were the most accurate and closest to measured RMR in both genders, in comparison to the Harris and Benedict, Ravussin and Bogardus, and Mifflin et al equation results. Estimated RMR using the latter equations was significantly lower than measured RMR in both genders at pre and post weight loss (P < 0.01).ConclusionsThis study highlights the need for adjusting RMR equations before and after weight loss in overweight and obese individuals. Further research is needed to validate our suggested equations.  相似文献   
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Atypical femur fractures (AFF) are a rare but serious complication of long-term bisphosphonate use. Although clearly defined by ASBMR criteria, a proportion of patients with AFFs may go unrecognized and the use of qualitative fracture criteria may lead to uncertainty in AFF diagnosis, with significant therapeutic implications. A score that rapidly and accurately identifies AFFs among subtrochanteric femur fractures using quantitative, measurable parameters is needed. In a retrospective cohort of 110 female patients presenting with AFFs or typical femur fractures (TFFs), multiple logistic regression and decision tree analysis were used to develop the Sydney AFF score. This score, based on demographic and femoral geometry variables, uses three dichotomized independent predictors and adds one point for each: (age ≤80 years) + (femoral neck width <37 mm) + (lateral cortical width at lesser trochanter ≥5 mm), (score, 0 to 3). In an independent validation set of 53 female patients at a different centre in Sydney, a score ≥2 demonstrated 73.3% sensitivity and 69.6% specificity for AFF (area under the receiver-operating characteristic curve [AUC] 0.775, SE 0.063) and remained independently associated with AFF after adjustment for bisphosphonate use. The Sydney AFF score provides a quantitative means of flagging female patients with atraumatic femur fractures who have sustained an AFF as opposed to a TFF. This distinction has clear management implications and may augment current ASBMR diagnostic criteria. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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