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Mature adult (3-6 months old) and aged (24-27 months old) male ICR mice were injected with 10 to 100 mg/kg morphine, SC. The ED50 values for locomotor behavior representing 5 times control activity were 7.5 mg/kg for aged mice and 17.8 mg/kg for the mature adults. There were striking age- and dose-dependent differences in both intensities and durations of morphine-induced locomotor activity. The ED50 values for antinociception 1 hour after morphine administration were 70 mg/kg for the aged mice and 13 mg/kg for the mature adults. One hour after injecting 30 and 100 mg/kg morphine tagged with 3H-morphine, 0.13 and 0.14 percent of the doses appeared in brains of aged and mature adult mice, respectively. Distribution of morphine among brain regions was the same for both age groups. The results suggest that the differences in response to morphine by the two age groups were due to age-related differences in affinities, numbers and/or functioning of opioid receptors and not to pharmacokinetic differences.  相似文献   
94.
BackgroundInertial Flywheel Resistance Training (IFRT) has recently emerged as a beneficial rehabilitation option for some musculoskeletal disorders. Although the use of resistance training as treatment for tendinopathy has become widespread, it is unclear if IFRT has efficacy as a treatment option for tendinopathies.ObjectiveTo identify current evidence on IFRT in the treatment of tendinopathy, evaluating intervention parameters and outcomes.MethodsThis scoping review was reported in accordance with the PRISMA Extension for Scoping Reviews (PRISMA-ScR). Databases searched included MEDLINE, CINAHL, AMED, EMBase, SPORTDiscus, Cochrane library (Controlled trials, Systematic reviews), and five trial registries. Two independent reviewers screened studies at title, abstract and full text. Following screening, data were extracted and charted, and presented as figures and tables alongside a narrative synthesis. Any study design conducted on adults, investigating the effects of IFRT for tendinopathy were included. Data were extracted on intervention parameters and outcomes of IFRT interventions.ResultsFour studies on patellar tendinopathy were included. A variety of outcomes were assessed, including pain, function, strength, power, and tendon morphological and mechanical properties, particularly changes in tendon thickness. IFRT intervention parameters were largely homogenously prescribed, with slight variances.ConclusionDespite a paucity of studies to date on the effects of IFRT for treating tendinopathy, preliminary evidence for beneficial effects of IFRT on clinical outcomes in patellar tendinopathy is encouraging. As IFRT is a relatively new and unexplored method in tendinopathy rehabilitation, definitive conclusions, and recommendations cannot be made at present, which should be addressed in future research, due to the potential therapeutic benefits highlighted in this review.  相似文献   
95.
Objective: To evaluate the relationship between first and second trimester maternal serum-free β-hCG and the risk of spontaneous preterm delivery (PTD).

Study design: This was a case-control study of women evaluated and delivered at our institution from 2011 to 2015. Spontaneous PTD was defined as delivery before 37 weeks due to spontaneous preterm labor or premature rupture of membranes. Patient with multifetal gestation and those with medically indicated term or PTD were excluded.

Results: Of 877 women meeting the inclusion criteria, 173 delivered preterm and 704 delivered at term, and 8.1% had high free β-hCG in one or both trimesters. High maternal first and/or second trimester free β-hCG (≥95th percentile) was associated with lower rates of PTD. Thirty-two women with high free β-hCG in both first and second trimesters delivered at term. Gestational age at delivery and birth weights were lower in women who did not have high free β-hCG in any trimester. Low free β-hCG (≤5th percentile) in either trimester was not associated with an increased or decreased likelihood of PTD. Logistic regression demonstrated an independent association of high free β-hCG (≥95th percentile) with a reduced likelihood of PTD. Stratified analysis revealed a stronger impact of this association in women with no prior history of PTD.

Conclusions: High free β-hCG, in the absence of risk factors for medically indicated PTD, is associated with a reduced likelihood of spontaneous PTD and may represent a marker indicating lower risk.  相似文献   

96.
Phenotype‐based diagnostic criteria were developed for Proteus syndrome in 1999 and updated in 2006. Subsequently, the causative mosaic gene alteration was discovered, the c.49G>A p.E17K variant in AKT1. As well, a number of overlapping overgrowth disorders attributable to mosaic PIK3CA variants have now been characterized, leading to the designation of PIK3CA‐related overgrowth spectrum (PROS). Finally, ongoing work to better characterize Proteus syndrome has led to identification of additional features of that disorder that could be useful in diagnostic criteria. We have taken the opportunity of these discoveries to re‐evaluate the Proteus syndrome diagnostic criteria. Here we propose a new set of diagnostic criteria that establishes a weighted, point‐based system for the phenotypic attributes and then integrates that with the potential molecular test results to result in one of two designations: AKT1‐related Proteus syndrome or AKT1‐related overgrowth spectrum. A patient whose only manifestation is an AKT1 c.49G>A‐positive tumor would receive neither of these designations. Here we review the rational basis of diagnostic criteria and argue that a unitary diagnostic entity is a distinct gene‐phenotype dyad and that this should be the model for all mendelian disorders. The gene‐alone or phenotype‐alone approach is inadequate to rigorously delineate a unitary diagnostic entity.  相似文献   
97.
Using longitudinal ethnographic data from the Three-City Study, we examined the relationship between sixteen low-income Puerto Rican mothers' housing dependencies and their intimate partner relations. We traced mothers' dependent housing arrangements and entrée to marital or cohabiting relationships from their teens through their procurement of independent housing while entering and maintaining intimate partner unions as adults. Findings indicated that various trigger factors led women out of their natal homes and into expedited cohabitation with romantic partners which frequently resulted in unstable unions in which mothers had little power and autonomy. As mothers became eligible for housing subsidies they obtained housing independent from their male partners, potentially increasing the propensity for greater relationship power. Housing independence, however, was not without problems. Spillover effects, such as shadowing partners, threatened housing stability and mothers' independence. The relevance of these findings for future research is discussed.  相似文献   
98.
Placental efficiency and adaptation: endocrine regulation   总被引:1,自引:1,他引:0  
Size at birth is critical in determining life expectancy and is dependent primarily on the placental supply of nutrients. However, the fetus is not just a passive recipient of nutrients from the placenta. It exerts a significant acquisitive drive for nutrients, which acts through morphological and functional adaptations in the placenta, particularly when the genetically determined drive for fetal growth is compromised by adverse intrauterine conditions. These adaptations alter the efficiency with which the placenta supports fetal growth, which results in optimal growth for prevailing conditions in utero . This review examines placental efficiency as a means of altering fetal growth, the morphological and functional adaptations that influence placental efficiency and the endocrine regulation of these processes.  相似文献   
99.
B19 parvovirus replicates in circulating cells of acutely infected patients   总被引:3,自引:0,他引:3  
Kurtzman  GJ; Gascon  P; Caras  M; Cohen  B; Young  NS 《Blood》1988,71(5):1448-1454
B19 parvovirus is the etiologic agent of fifth disease and transient aplastic crisis. In natural infections, B19 antigen and DNA have been detected in sera early in the course of aplastic crisis and only rarely in fifth disease. We have found B19 DNA in circulating cells of infected patients by DNA dot blot with a virus-specific probe: in four of four sickle cell patients with aplastic crisis, in one asymptomatic sibling, and in one normal adult with fifth disease. Only two of the sera showed B19 DNA. High-molecular weight intermediate forms were detected by Southern analysis of DNA extracted from cells, thus indicating active replication of virus in cells rather than passive adsorption to their surface membranes. Separation of cells into high- and low-density fractions resulted in a concentration of the virus DNA in the granulocytic fraction.  相似文献   
100.
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