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After 30 years of hematopoietic stem cell use for various indications, umbilical cord blood is considered as an established source of cells with marrow and postmobilization peripheral blood. The limited number of cells still remains a problematic element restricting their use, especially in adults who require to be grafted with a higher cell number. Improving the quality of harvested cord blood, at least in terms of volume and amount of cells, is essential to decrease the number of discarded units. In this review, we examine several variables related to parturient, pregnancy, labor, delivery, collection, the newborn, umbilical cord, and placenta. We aim to understand the biologic mechanisms that can impact cord blood quality. This knowledge will ultimately allow targeting donors, which could provide a rich graft and improve the efficiency of the collection.  相似文献   
998.

Objective

To examine whether a Rasch analysis is sufficient to establish the construct validity of the Motor Function Measure (MFM) and discuss whether weighting the MFM item scores would improve the MFM construct validity.

Design

Observational cross-sectional multicenter study.

Setting

Twenty-three physical medicine departments, neurology departments, or reference centers for neuromuscular diseases.

Participants

Patients (N=911) aged 6 to 60 years with Charcot-Marie-Tooth disease (CMT), facioscapulohumeral dystrophy (FSHD), or myotonic dystrophy type 1 (DM1).

Interventions

None.

Main Outcome Measure(s)

Comparison of the goodness-of-fit of the confirmatory factor analysis (CFA) model vs that of a modified multidimensional Rasch model on MFM item scores in each considered disease.

Results

The CFA model showed good fit to the data and significantly better goodness of fit than the modified multidimensional Rasch model regardless of the disease (P<.001). Statistically significant differences in item standardized factor loadings were found between DM1, CMT, and FSHD in only 6 of 32 items (items 6, 27, 2, 7, 9 and 17).

Conclusions

For multidimensional scales designed to measure patient abilities in various diseases, a Rasch analysis might not be the most convenient, whereas a CFA is able to establish the scale construct validity and provide weights to adapt the item scores to a specific disease.  相似文献   
999.

Objective

To compare the effects of classic progressive resistance training (PRT) versus eccentric strength-enhanced training (EST) on the performance of functional tests and different strength manifestations in the lower limb of people with multiple sclerosis (PwMS).

Design

Experimental trial.

Setting

Strength training program.

Participants

PwMS (N=52; 19 men, 33 women) belonging to MS associations from the Castilla y León, Spain.

Interventions

Participants were assigned to 1 of 2 groups: a control group that performed PRT or an experimental group that performed EST. In both groups, the knee extensor muscles were trained for 12 weeks.

Main Outcome Measures

Before and after 12 weeks of training, maximal voluntary isometric contraction and 1 repetition maximum (1RM) of the knee extensors were evaluated, as were the Chair Stand Test (CST) and Timed 8-Foot Up and Go (TUG) functional tests.

Results

No differences were found between the groups in the initial values for different tests. Intragroup comparisons found significant differences in CST (F=69.4; P<.001), TUG (F=40.0; P<.001), and 1RM (F=57.8; P<.001). For intergroup comparisons, EST presented better results than PRT in the CST (EST, 4.7%±2.8%; PRT, 1.9%±2.8%; F=13.1; P=.001) and TUG (EST, ?2.9±4.7; PRT, ?.41±5.6; F=5.6; P=.022).

Conclusions

In PwMS, EST leads to improvements in 1RM, TUG, and CST that are similar to those of PRT. However, for patients who participated in this study, the EST seems to promote a better transfer of strength adaptations to the functional tests, which are closer to daily-living activities.  相似文献   
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