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The Artelon CMC spacer (Small Bone Innovations, Inc., Morrisville, PA) is a relatively new device that was developed for the treatment of basal joint arthritis. It is composed of a biodegradable polycaprolactone-based polyurethane urea that acts to resurface the distal part of the trapezium and stabilize the trapeziometacarpal joint by augmenting the joint capsule. This is a case report of a foreign-body tissue reaction to the Artelon CMC spacer.  相似文献   
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In the study reported here, we evaluated 2-screw femoral neck fixation. Femoral necks from 5 paired fresh-frozen cadavers were fractured and then fixed with two 7.3-mm cannulated cancellous screws. Vertical (parallel screws in sagittal plane of femoral neck) and horizontal (parallel screws in superior aspect of femoral neck) configurations were used for each matched pair. Mechanical testing was performed. Load, displacement, and stiffness at the yield point were significantly higher in the horizontal group, which also had a higher mean maximal failure load (P = .019). Preliminary data suggest that 2 horizontal screws in the superior aspect of the femoral neck provide more secure fixation than 2 vertical screws.  相似文献   
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The purpose is to examine the relationship between musculoskeletal fitness and health status. Muscular strength is positively associated with independence and overall quality of life, and negatively associated with morbidity and potentially premature mortality. Muscular endurance is positively related to overall quality of life. Elevated muscular endurance may reduce the incidence of falling and its associated injuries. Muscular power is predictive of functional capacity, resultant disability, and potentially premature mortality. Flexibility is positively associated with mobility and independence. Women and the aged may be susceptible to musculoskeletal impairments leading to reduced health status and thus may represent primary target groups for intervention programs. High levels of musculoskeletal fitness are associated with positive health status, and low levels of musculoskeletal fitness are associated with lower health status.  相似文献   
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Background  

Down syndrome (DS) is caused by trisomy 21 (+21), but the aberrations in gene expression resulting from this chromosomal aneuploidy are not yet completely understood.  相似文献   
78.
The psychological autopsy is an important assessment tool used to identify aspects of a person's life that explain any lingering mystery that shrouds their death. In addition to answering questions of the past, the psychological autopsy has significant implications for the future. Statistics obtained from mortality data affect the course of health care research, the flow of resources, and ultimately public health policy. From a public health perspective, the misclassification of suicides as accidents or deaths from natural causes can negatively affect research funding and policy development related to suicide prevention efforts, making a standardized and accurate procedure imperative. Although the psychological autopsy was developed initially as a tool to assist the coroner in clarifying the cause of death, this procedure has transcended the confines of forensic science and has applications in the many arenas of litigation and public health policy.  相似文献   
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We found that the human colon cancer cell line SW480 consists of two distinct subpopulations which we have designated E-type (epithelial) and R-type (round). Pure cultures of each type were obtained by subcloning, and both have maintained their characteristic phenotypes for at least 1 year (40 passages). E-type cells are the major (> 98%) type in the parental SW480 cell line. They form flat epithelial-like colonies. In contrast, R-type cells, which constitute a minor fraction (< 2%) of the parental cell line, have a rounded shape and grow in clusters of piled-up cells. Compared to E-type cells or the parental SW480 cells, isolated R-type cells display decreased doubling time, loss of contact inhibition, less adhesiveness to culture plates, higher anchorage-independent growth in soft agar, and a much more aneuploid karyotype. When injected s.c. into nude mice, R-type cells produce much larger tumors within the same period of time than E-type cells, and the tumors are less differentiated than those produced by the E-type cells. Cell fusion experiments between R-type and E-type cells revealed that the R-type phenotype is dominant, and the results suggest that this is due to one or a few genetic changes. Taken together, these findings suggest that the R-type cells represent a more malignant variant of the E-type cells. They may be useful, therefore, for studying mechanisms involved in tumor progression.  相似文献   
80.
Latent inhibition (LI) is a behavioural phenomenon whereby preexposure to a stimulus without reinforcement interferes with the formation of subsequent associations to that stimulus. Using preexposure to a tone stimulus which subsequently serves as a conditioned stimulus for suppression of licking, we have confirmed that LI is disrupted by a low dose of amphetamine. Haloperidol was able to prevent this effect of amphetamine. Ondansetron, a selective and potent 5HT3 receptor antagonist, was also shown to be effective at blocking the amphetamine-induced disruption of LI at a dose of 0.01 mg/kg, but not at 0.1 mg/kg. In addition, it was demonstrated that ondansetron could enhance LI; using only ten preexposures, no LI was obtained in the saline group, but was apparent in animals given ondansetron, an effect which has been previously shown with haloperidol. Haloperidol, at the higher dose used, reduced suppression of licking, however, ondansetron at the effective dose had no such effect. It is concluded that ondansetron is able to attenuate increases in dopamine activity, produced pharmacologically with amphetamine without affecting baseline dopamine activity. The implications of these findings for a possible antipsychotic action of ondansetron are discussed.  相似文献   
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