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81.
Low intensity resistance exercise (RE) with blood flow restriction (BFR) has gained attention in the literature due to the beneficial effects on functional and morphological variables, similar to those observed during traditional RE without BFR, while the effects of BFR on post-exercise hypotension remain unclear. The aim of the present study was to compare the blood pressure (BP) response of trained normotensive individuals to RE with and without BFR. In this cross-over randomized trial, eight male subjects (23.8 ± 4 years, 74 ± 3 kg, 174 ± 4 cm) completed two exercise protocols: traditional RE (3 x 10 repetitions at 70% one-repetition maximum [1-RM]) and low intensity RE (3 x 15 repetitions at 20% 1-RM) with BFR. Blood pressure measurements were performed after 15 min of seated rest (0), immediately after and 10 min, 20 min, 30 min, 40 min, 50 min and 60 min after the experimental sessions. Similar hypotensive effects for systolic BP (SBP) were observed for both protocols (P < 0.05) after exercise, with no differences between groups (P > 0.05) and no statistically significant difference for diastolic BP (P > 0.05). These results suggest that in normotensive trained individuals, both traditional RE and RE with BFR induce hypotension for SBP, which is important to prevent cardiovascular disturbances.  相似文献   
82.

Background and methods

Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.

Results

We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.

Conclusion

HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely.  相似文献   
83.

Background

Loss of arm-hand performance due to a hemiparesis as a result of stroke or cerebral palsy (CP), leads to large problems in daily life of these patients. Assessment of arm-hand performance is important in both clinical practice and research. To gain more insight in e.g. effectiveness of common therapies for different patient populations with similar clinical characteristics, consensus regarding the choice and use of outcome measures is paramount. To guide this choice, an overview of available instruments is necessary. The aim of this systematic review is to identify, evaluate and categorize instruments, reported to be valid and reliable, assessing arm-hand performance at the ICF activity level in patients with stroke or cerebral palsy.

Methods

A systematic literature search was performed to identify articles containing instruments assessing arm-hand skilled performance in patients with stroke or cerebral palsy. Instruments were identified and divided into the categories capacity, perceived performance and actual performance. A second search was performed to obtain information on their content and psychometrics.

Results

Regarding capacity, perceived performance and actual performance, 18, 9 and 3 instruments were included respectively. Only 3 of all included instruments were used and tested in both patient populations. The content of the instruments differed widely regarding the ICF levels measured, assessment of the amount of use versus the quality of use, the inclusion of unimanual and/or bimanual tasks and the inclusion of basic and/or extended tasks.

Conclusions

Although many instruments assess capacity and perceived performance, a dearth exists of instruments assessing actual performance. In addition, instruments appropriate for more than one patient population are sparse. For actual performance, new instruments have to be developed, with specific focus on the usability in different patient populations and the assessment of quality of use as well as amount of use. Also, consensus about the choice and use of instruments within and across populations is needed.  相似文献   
84.
85.
The Aschelminthes is a collection of at least eight animal phyla, historically grouped together because the absence of a true body cavity was perceived as a pseudocoelom. Analyses of 18S rRNA sequences from six Aschelminth phyla (including four previously unpublished sequences) support polyphyly for the Aschelminthes. At least three distinct groups of Aschelminthes were detected: the Priapulida among the protostomes, the Rotifera-Acanthocephala as a sister group to the protostomes, and the Nematoda as a basal group to the triploblastic Eumetazoa.   相似文献   
86.
The period (per) locus has received much attention in molecular evolution studies because it is one of the best studied "behavioral genes" and because it offers insight into the evolution of repetitive sequences. We studied most of the coding region of per in Drosophila willistoni and confirmed previously observed patterns of conservation and divergence among distantly related species. Five regions are so highly diverged that they cannot be aligned, whereas a region encompassing the PAS domain is very conserved. Structural and nucleotide polymorphism patterns in the willistoni group are not the same as those observed in previously studied species. We sequenced the region homologous to the highly polymorphic threonine-glycine repeat of D. melanogaster in multiple strains of D. willistoni, as well as in other members of willistoni group, and found an unusual amount of conservation in this region. However, the next nonconserved region downstream in the sequence is quite variable and polymorphic for the number of repeated glycines. The glycine codon usage is significantly different in this glycine repeat as compared to other parts of the gene. We were able to plot the directionality of change in the glycine repeat region onto a phylogeny and find that the addition of glycines is the general trend with the diversification of the willistoni group.   相似文献   
87.
The monovalent ionophore, monensin, inhibits secretion of many different proteins from a wide variety of cells. The site of blockage is at the golgi complex. We have exposed chick embryo chondrocytes in suspension culture to monensin, at concentrations ranging from 10(-8) to 10(-6) M. At the higher concentrations, between 10(-7) and 10(-6) M, monensin inhibited secretion of type II procollagen, which accumulated in the chondrocytes. At these concentrations of the ionophore, proteoglycan synthesis was inhibited, as measured by radioactive serine incorporation into core proteins and by radioactive glucosamine or SO4 incorporation into glycosaminoglycans. However, at a monensin concentration of 3 x 10(-8) M, the incorporations of serine and glucosamine were close to normal while SO4 incorporation was at 30% of control values. The ratio of glucosamine to serine in pronase-released glycosaminoglycans from culture media was unaffected by 3 x 10(-8) M monensin but the sulfate to serine ratio decreased to 29% of control values. Examination of the glycosaminoglycans by gel filtration showed a progressive increase in Kav values as sulfation decreased. Undersulfation was demonstrated by radiochromatographic analysis of the digestion products following incubation with chondroitinase ABC. The composite results show that monensin interferes with sulfation of newly synthesized proteoglycans.  相似文献   
88.
EXPERIMENTAL LATHYRISM : An Autoradiographic Study   总被引:1,自引:0,他引:1       下载免费PDF全文
In normal and lathyritic chick embryos bone collagen was synthesized primarily in the periosteum of the femurs, and was organized as radioactive spicules in these bones. Saline extraction of the lathyritic bones removed the radioactive spicules, although they eventually seemed to become non-extractable. Normal bone seemed to be unaffected by saline extraction. Marked variation in the degree of isotope incorporation was seen in collagenous and non-collagenous tissues. All the tissues of any one embryo, however, showed a similar degree of isotope incorporation. Tritiated β-aminopropionitrile was diffusely distributed throughout bone and was completely removed by saline extraction. This autoradiographic study supports the postulate that a portion of extractable lathyritic collagen is recently synthesized and is organized in fibrous structures in bone.  相似文献   
89.
Evidence is presented that B+ null lymphocyte supernatants, previously shown to promote the growth of CD4+ T lymphocyte colonies from human marrow precursors, can also selectively enhance CD4+ T cell proliferative response to PHA and IL2.  相似文献   
90.
A genomic DNA fragment (gCORE-1), encoding a portion of the cartilage proteoglycan core protein, has been isolated from a phage library using cDNA as a probe. The genomic insert is about 17 kilobase pairs; two BamHI fragments of the insert (1.3 and 4.8 kilobase pairs) contain most of the hybridizable sequences found in the cDNA. Sequence analysis of these fragments shows that they contain a total of five exons that encompass 216 amino acid residues, all of which are identical to those of the corresponding cDNA sequence. Three of the exons, which are adjacent to one another, are very similar to the corresponding exons in the gene of a rat hepatic lectin as well as to an exon in the gene of human pulmonary surfactant-associated protein. There is a strong degree of conservation of amino acid sequences encoded in the three genes, although there is no similarity between their introns. The sizes of the five exons in gCORE-1, except for one (which is indeterminate because only a partial cDNA sequence is available), are less than 184 base pairs, whereas the sizes of the introns range from 218 to greater than 2629 base pairs. Four of the introns interrupt an exon codon at either their donor or acceptor sites, between the first and second nucleotides. Only one intron does not split a codon. Intron and exon boundary sites are in agreement with known consensus sequences for introns. The dispersed distribution and relatively small size of the exons, if representative of the entire gene, suggest that the complete gene which codes for the core protein may be quite sizable.  相似文献   
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