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61.
The objective of this study was to analyze the psychometric properties of the English and Spanish S-TOFHLA for three patient populations of interest. Despite being widely used, little is written about psychometric properties of the S-TOFHLA, particularly the Spanish version. Participants were Medicaid and Medicare patients: 936 non-Hispanic and 368 Hispanic patients completed the English S-TOFHLA; 1066 Hispanics completed the Spanish S-TOFHLA. Validity of both versions of the S-TOFHLA was supported by strong positive relationships with education and inverse relationships with age. Significant differences between scores for men and women remained after adjusting for level of education. Score differences occurred across numerous items. More research is needed on the S-TOFHLA and other health literacy instruments to determine why women score differently than men. Variability in literacy skills within subgroups of patients highlights the importance of healthcare providers being sensitive to patients' literacy levels in both spoken and written communications.  相似文献   
62.
The role of autophagy, a catabolic lysosome-dependent pathway, has recently been recognized in a variety of disorders, including Pompe disease, the genetic deficiency of the glycogen-degrading lysosomal enzyme acid-alpha glucosidase. Accumulation of lysosomal glycogen, presumably transported from the cytoplasm by the autophagic pathway, occurs in multiple tissues, but pathology is most severe in skeletal and cardiac muscle. Skeletal muscle pathology also involves massive autophagic buildup in the core of myofibers. To determine if glycogen reaches the lysosome via autophagy and to ascertain whether autophagic buildup in Pompe disease is a consequence of induction of autophagy and/or reduced turnover due to defective fusion with lysosomes, we generated muscle-specific autophagy-deficient Pompe mice. We have demonstrated that autophagy is not required for glycogen transport to lysosomes in skeletal muscle. We have also found that Pompe disease involves induction of autophagy but manifests as a functional deficiency of autophagy because of impaired autophagosomal-lysosomal fusion. As a result, autophagic substrates, including potentially toxic aggregate-prone ubiquitinated proteins, accumulate in Pompe myofibers and may cause profound muscle damage.  相似文献   
63.
Scedosporium spp. are increasingly recognized as causes of resistant life-threatening infections in immunocompromised patients. Scedosporium spp. also cause a wide spectrum of conditions, including mycetoma, saprobic involvement and colonization of the airways, sinopulmonary infections, extrapulmonary localized infections, and disseminated infections. Invasive scedosporium infections are also associated with central nervous infection following near-drowning accidents. The most common sites of infection are the lungs, sinuses, bones, joints, eyes, and brain. Scedosporium apiospermum and Scedosporium prolificans are the two principal medically important species of this genus. Pseudallescheria boydii, the teleomorph of S. apiospermum, is recognized by the presence of cleistothecia. Recent advances in molecular taxonomy have advanced the understanding of the genus Scedosporium and have demonstrated a wider range of species than heretofore recognized. Studies of the pathogenesis of and immune response to Scedosporium spp. underscore the importance of innate host defenses in protection against these organisms. Microbiological diagnosis of Scedosporium spp. currently depends upon culture and morphological characterization. Molecular tools for clinical microbiological detection of Scedosporium spp. are currently investigational. Infections caused by S. apiospermum and P. boydii in patients and animals may respond to antifungal triazoles. By comparison, infections caused by S. prolificans seldom respond to medical therapy alone. Surgery and reversal of immunosuppression may be the only effective therapeutic options for infections caused by S. prolificans.  相似文献   
64.

Purpose

In vitro follicle growth (IVFG) is an investigational fertility preservation technique in which immature follicles are grown in culture to produce mature eggs that can ultimately be fertilized. Although progress has been made in growing primate primary and secondary follicles in vitro, it has been a relatively greater challenge to isolate and culture primordial follicles. The purpose of this study was to develop methods to grow human primordial follicles in vitro using alginate hydrogels.

Methods

We obtained human ovarian tissue for research purposes through the National Physicians Cooperative from nationwide sites and used it to test two methods for culturing primordial follicles. First, primordial follicles were isolated from the ovarian cortex and encapsulated in alginate hydrogels. Second, 1 mm × 1 mm pieces of 500 μm-thick human ovarian cortex containing primordial follicles were encapsulated in alginate hydrogels, and survival and follicle development within the tissue was assessed for up to 6 weeks.

Results

We found that human ovarian tissue could be kept at 4 °C for up to 24 h while still maintaining follicle viability. Primordial follicles isolated from ovarian tissue did not survive culture. However, encapsulation and culture of ovarian cortical pieces supported the survival, differentiation, and growth of primordial and primary follicles. Within several weeks of culture, many of the ovarian tissue pieces had formed a defined surface epithelium and contained growing preantral and antral follicles.

Conclusions

The early stages of in vitro human follicle development require the support of the native ovarian cortex.  相似文献   
65.
66.

Purpose

The psychosocial determinants of prediabetes are poorly understood. The aims of our study were (1) to analyse the association between perceived social support in young adulthood and fasting glucose levels and prediabetes in mid-adulthood in a cohort of healthy Finns, (2) to explore whether body mass index (BMI), inflammation or depression mediate this relationship, (3) and to examine the association between social support trajectory groups and fasting glucose.

Method

A prospective design was used with an analytic sample of 1250 participants aged 3–18 years at baseline (1980) and aged 12–39 years when social support was measured. Fasting glucose and prediabetes were assessed 32 years after baseline. Linear and logistic regression was used to examine the association between social support and the outcome measures. A bootstrapping technique was used to examine mediation effects.

Results

Social support was associated with future glucose levels in women after adjusting for childhood socioeconomic status (SES) and youth depression (β = ?0.136, p = 0.001) and also predicted prediabetes in women after adjusting for childhood SES (β = 1.31, 95 % CI 1.02 to 1.69, p = 0.031). Both associations were attenuated after adjusting for BMI in mid-adulthood. BMI was found to mediate the relationship between social support and prediabetes in women (β for indirect effect β = 0.09, SE = 0.03, CI = 0.03 to 0.16).

Conclusion

Low perceived social support in young adulthood is associated with high fasting glucose and prediabetes in mid-adulthood in women but not men. The association between social support and prediabetes in women can be partly explained by BMI.
  相似文献   
67.
This article is the result of a panel discussion on future directions in personality disorders held at the 1998 Meeting of the Society for Psychotherapy Research in Snowbird Utah. Three experts in the field of personality disorders were invited to participate in a dialogue on priorities and directions for research, practice, and policy in this area. Topics discussed amongst the panelists included the following: 1) relevance of psychotherapy process research for treatments of personality disorders, and potential fruitful directions for such research; 2) what has been learned from outcome research in treatment of personality disorders, and directions for such research that are likely to be most productive in improving treatments; 3) the extent to which research has influenced clinical practice and how existing gaps might be addressed; 4) policy questions related to payment for treatment of personality disorders.  相似文献   
68.
Both discrete and continuous bimanual coordination patterns are difficult to effectively perform when the two limbs are required to perform different movements patterns, move at different velocities and/or move different amplitudes unless some form of integrated feedback is provided. The purpose of the present experiment was to determine the degree to which a complex bimanual coordination pattern could be performed when integrated feedback and movement template are provided. The complex bimanual coordination pattern involved reciprocal movements of the two limbs under different difficulty requirements. As defined by Fitts’ index of difficulty (ID), the left arm (ID = 3, A = 16°, W = 4°) task was of lower difficulty than the right arm task (ID = 5, A = 32°, W = 2°). Note that the left and right limb movements are also different in terms of movement time, movement velocity, accuracy requirements and amplitude as well as one movement was continuous and the other intermittent. Participants were provided 2 blocks of 9 trials in the bimanual condition (30 s/trial). Following the bimanual phase, participants performed two unimanual test trials—one with each limb. The results demonstrated that the performance for each limb in the bimanual condition was similar to the performance for the same limb and conditions in the unimanual control conditions. The similarity was indicated by the same movement speed, movement structure, endpoint variability and hit rates for the bimanual and unimanual conditions. The results support our hypothesis that people can overcome the intrinsic difficulties associated with performing complex bimanual coordination patterns when provided appropriate perceptual information feedback that allows them to detect and correct coordination errors.  相似文献   
69.
An experiment was designed to determine the effectiveness of auditory and visual models in the learning of a 2:3 bimanual tapping pattern. Participants were randomly assigned to an auditory model, visual model, auditory + visual model, or a control (visual metronome) group. The task for all groups was to tap a left side force transducer with the left hand and a right side force transducer with the right hand in attempt to produce the desired 2:3 bimanual coordination pattern. The auditory model consisted of a series of tones representing the goal pattern played prior to each practice trial. The visual model consisted of a visual display representing the goal tapping pattern. Visual pacing metronomes were provided to the control group. The right and left side metronomes flashed during the trial in a pattern representing the goal tapping pattern. Subjects in all groups performed 14 practice trials consisting of 15 s each devoted to tapping the goal pattern (total practice time = 3.5 min). A retention test without the aid of the models or metronomes was administered following the practice trials. The results for the model groups indicated extremely effective performance of the bimanual coordination patterns for the auditory, visual, and auditory + visual model conditions with not only the relative, but also the absolute characteristics of the models exhibited during retention testing. Retention performance for the visual metronome condition was less accurate and more variable than the three model conditions. In addition, the auditory + visual model condition resulted in retention performance that was more stable than the auditory model condition.  相似文献   
70.
Porous carriers for biomedical applications based on alginate hydrogels   总被引:9,自引:0,他引:9  
Eiselt P  Yeh J  Latvala RK  Shea LD  Mooney DJ 《Biomaterials》2000,21(19):1921-1927
Macroporous scaffolds are typically utilized in tissue engineering applications to allow for the migration of cells throughout the scaffold and integration of the engineered tissue with the surrounding host tissue. A method to form macroporous beads with an interconnected pore structure from alginate has been developed by incorporating gas pockets within alginate beads, stabilizing the gas bubbles with surfactants, and subsequently removing the gas. Macroporous scaffolds could be formed from alginate with different average molecular weights (5-200 kDa) and various surfactants. The gross morphology, amount of interconnected pores, and total void volume was investigated both qualitatively and quantitatively. Importantly, macroporous alginate beads supported cell invasion in vitro and in vivo.  相似文献   
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