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61.
Randomized controlled trials are considered the most rigorous research design in efficacy and effectiveness research; however, such trials present numerous challenges that limit their applicability in real-world settings. As a consequence, pragmatic trials are increasingly viewed as a research design that overcomes some of these barriers with the potential to produce findings that are more reproducible. Although pragmatic methodology in long-term care is receiving increasing attention as an approach to improve successful dissemination and implementation, pragmatic trials present complexities of their own. To address these complexities and related issues, experts with experience conducting pragmatic trials, developing nursing home policy, participating in advocacy efforts, and providing clinical care in long-term care settings participated in a virtual consensus conference funded by the National Institute on Aging in Spring 2021. Participants identified 4 cross-cutting principles key to dissemination and implementation of pragmatic trial interventions: (1) stakeholder engagement, (2) diversity and inclusion, (3) organizational strain and readiness, and (4) learn from adaptations. Participants emphasized that implementation processes must be grounded in the perspectives of the people who will ultimately be responsible for implementing the intervention once it is proven to be effective. In addition, messaging must speak to long-term care staff and all others who have a stake in its outcomes. Although our understanding of dissemination and implementation strategies remains underdeveloped, this article is designed to guide long-term care researchers and community providers who are increasingly aware of the need for pragmatism in disseminating and implementing evidence-based care interventions.  相似文献   
62.
Human laboratory studies play an important role in alcohol use disorder (AUD) medication development. Medications that are found to be safe and effective during human laboratory screening will then move to more expensive clinical trials in patient populations. Given the gatekeeping role of human laboratory studies in the medication development pipeline, it is critical that these studies accurately forecast how pharmacotherapies will perform under true-to-life clinical conditions. On the other hand, the design of these studies also must adhere to ethical guidelines: certain aspects of clinical reality cannot be incorporated into screening studies because doing so might place the participant at risk for harm or breach other ethical guidelines. Conventions exist that guide the resolution of these conflicting ideals. This article considers the practice of recruiting non–treatment-seeking heavy drinkers to participate in laboratory screening studies. By convention, volunteers are excluded from laboratory screening studies that involve alcohol administration if they are deemed “treatment seeking,” meaning that they recently stopped drinking or are motivated to do so. Although this common practice may reduce risk to participants, findings may not accurately predict medication effects on treatment seekers. Indeed, there is empirical evidence that treatment seekers differ from nontreatment seekers in their responses to medications (Neuropsychopharmacology 2017a; 42: 1776; Am J Drug Alcohol Abuse 2017b; 43: 703; J Psychiatr Res 2006; 40: 383). Here, we argue for the importance of recruiting treatment seekers for this research due to their qualitative difference from nontreatment seekers. We argue that these individuals should be the default population in human laboratory medication screening studies. We conclude by discussing 2 case examples of medication experiments led by our research groups that involved administering medications to treatment seekers.  相似文献   
63.
3-nitropropionic acid (3-NPA) neurotoxicity and long-term effects of perinatal hypoxia were evaluated in 18 adult rats. Hypoxia-insulted (I) and noninsulted (NI) rats were delivered by cesarean section. Hypoxic insult was effected by submerging dissected uterine horns in warmed saline for 15 min. NI rats were delivered from the adjacent nonsubmerged horns. At postnatal day 90, I and NI rats were trained to perform tasks thought to measure behaviors dependent upon aspects of time estimation (TE), motivation, and learning. At 12 months of age, rats were injected i.p. with escalating doses of 3-NPA (5 mg/kg/day to a maximum of 30 mg/kg/day) immediately after each test session and sacrificed at the end of treatment. Additional male rats were used as untreated controls. Although 3-NPA produced a dose-dependent impairment of performance in each task, the effects were qualitatively similar for each group. A significant difference between I and NI rats was, however, observed in the TE task where NI rats completed less of the task at high doses of 3-NPA compared to I rats. Compared to untreated controls, dopamine concentrations were decreased in caudate nucleus of both I and NI rats after 3-NPA. Specific areas most frequently damaged included cerebral cortex, hippocampal subfield CA1, thalamus, caudate nucleus, and the cerebellum. Lesions usually were less extensive in the I rather than NI members of a littermate pair, suggesting a possible protective effect of perinatal hypoxia against subsequent 3-NPA neurotoxicity.  相似文献   
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Idiopathic musculoskeletal pain syndromes in children have a variety of manifestations; they can be diffuse or well localized, constant or intermittent, with or without autonomic symptoms and signs, completely incapacitating or not limiting activities, and they can tax the physician's diagnostic skill. A careful history and examination is usually all that is needed to make a diagnosis, although the differential diagnosis is large and might require laboratory and radiographic investigation. Pain and functional assessment help track the progress with therapy. Intense exercise therapy is associated with the best outcome. Psychologic issues should be evaluated to determine if further psychologic intervention is indicated. The medium-term outcome is probably good for most of these children, but the long-term prognosis is unknown. One must be aware that other manifestations of psychologic problems might emerge. By the time these children and their families see the rheumatologist they are desperate and can be frustrating to work with due to their difficulty in accepting any kind of psychologic element to the pain and its associated disability. Nevertheless, it is rewarding to help the children understand and work through their pain so they can resume normal lives.  相似文献   
67.
In a partial, two-way crossover study of gastric emptying (GE) in spinal cord injury (SCI), fasted, healthy, unmedicated male volunteers were given a 99mTc-labeled liquid meal on two occasions. Metoclopramide (10 mg) was administered intravenously to each subject before the second evaluation of GE. We used single and multiexponential models with linear and nonlinear least-squares regression techniques to study the time-course of the disappearance of 99mTc from the stomach. The GE pattern in all subjects was most accurately characterized by nonlinear analysis (NONLIN) and consisted of two components, an initial adynamic phase and a phase of rapid emptying. The GE t1/2 of a liquid meal decreased from 106.6 +/- 58.3 min (mean +/- SD) in all SCI subjects (quadriplegic plus paraplegic) prior to treatment to 21.6 +/- 8.2 min after the intravenous administration of metoclopramide (p less than 0.006). Significant correlations between GE t1/2 and injury duration (yr) or level of spinal injury were observed. Impaired gastric emptying in SCI can be pharmacologically modified by metoclopramide to resemble a normal gastric emptying profile. Metoclopramide-altered gastric emptying in SCI may be expected to result in changes in the therapeutic efficacy of orally administered drugs when drug absorption is dependent on gastric motility or emptying efficiency.  相似文献   
68.
Crack cocaine users are at high risk for HIV, with higher frequency crack users engaging in higher rates of HIV-related sexual risk behaviors. This study will assess the variables impacting changes in crack use frequency. Out-of-treatment crack users were street recruited in East Harlem, NY. Subjects (n = 727) were 33% female, 91% minority, and 28% reported recent drug injecting. Baseline and 6-month follow-up interviews were administered. There was a significant reduction in crack use over time (p < .0001). Subjects were categorized according to five groups, based on their change in level of crack use between the two interviews, to predict those who stopped, maintained, or changed their level of use. Discriminant analyses identified six variables as the best predictors of the five groups, including having been in drug treatment since baseline and having been a drug injector (both related to reduced levels of crack use). The overall reduction in crack use for the sample masked the fact that important subgroups remained at high use levels or increased their use. The identification of subgroups who may be most resistant to reducing drug use can be helpful in developing more effective interventions.  相似文献   
69.
Inflammatory breast cancer is a distinct clinicopathologic entity that accounts for 1 percent of all cases of breast cancer. The diagnosis should be strongly suspected on the basis of the distinctive clinical findings, which include edema of the breast, inflammation, wheals, and a typical reddish-purple color of the overlying skin. Pathologic examination usually shows infiltration of the dermal lymphatics with carcinoma. Evidence of distant metastatic spread is more frequent than with other types of breast cancer and is seen in approximately 30 percent of patients. The five-year disease-free survival rate is less than 5 percent when local therapy alone (mastectomy and/or local radiotherapy) is used. The addition of combination chemotherapy to high-dose local radiotherapy has improved the five-year survival rate to approximately 30 percent. The potential for long-term survival is limited to the subgroup of patients with only local-regional disease at the time of diagnosis. Patients with inflammatory breast cancer should be treated with combined-modality therapy using combination chemotherapy and high-dose radiotherapy to the breast, since this approach is potentially curative. The fatalism formerly associated with this diagnosis is no longer warranted, particularly in patients with local-regional disease. Failure to employ intensive combined-modality treatment will deny some patients a chance for long-term survival.  相似文献   
70.
Hyperlipidemia promotes the chronic inflammatory disease atherosclerosis through poorly understood mechanisms. Atherogenic lipoproteins activate platelets, but it is unknown whether platelets contribute to early inflammatory atherosclerotic lesions. To address the role of platelet aggregation in diet-induced vascular disease, we studied beta3 integrin-deficient mice (lacking platelet integrin alphaIIbbeta3 and the widely expressed nonplatelet integrin alphavbeta3) in two models of atherosclerosis, apolipoprotein E (apoE)-null and low-density lipoprotein receptor (LDLR)-null mice. Unexpectedly, a high-fat, Western-type (but not a low-fat) diet caused death in two-thirds of the beta3-/-apoE-/- and half of the beta3-/-LDLR-/- mice due to noninfectious pneumonitis. In animals from both models surviving high-fat feeding, pneumonitis was absent, but aortic atherosclerosis was 2- to 6-fold greater in beta3-/- compared with beta+/+ littermates. Expression of CD36, CD40L, and CD40 was increased in lungs of beta3-/-LDLR-/- mice. Each was also increased in smooth muscle cells cultured from beta3-deficient mice and suppressed by retroviral reconstitution of beta3. These data show that the platelet defect caused by alphaIIbbeta3 deficiency does not impair atherosclerotic lesion initiation. They also suggest that alphavbeta3 has a suppressive effect on inflammation, the loss of which induces atherogenic mediators that are amplified by diet-induced hyperlipidemia.  相似文献   
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