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排序方式: 共有163条查询结果,搜索用时 31 毫秒
71.
Tomasz Piontek Kinga Ciemniewska-Gorzela Andrzej Szulc Jakub Naczk Martyna Wardak Tadeusz Trzaska Witold Dudzinski Monika Grygorowicz 《PloS one》2013,8(12)
Objective
The aim of the study was to: 1) evaluate the differences in pre-post operative knee functioning, mechanical stability, isokinetic knee muscle strength in simultaneous arthroscopic patients after having undergone an anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL) with hamstring tendons reconstruction, 2) compare the results of ACL/PCL patients with the control group.Design
Controlled Laboratory Study.Materials and Methods
Results of 11 ACL/PCL patients had been matched with 22 uninjured control participants (CP). Prior to surgery, and minimum 2 years after it, functional assessment (Lysholm and IKDC 2000), mechanical knee joint stability evaluation (Lachman and “drawer” test) and isokinetic tests (bilateral knee muscle examination) had been performed. Different rehabilitation exercises had been used: isometric, passive exercises, exercises increasing the range of motion and proprioception, strength exercises and specific functional exercises.Results
After arthroscopy no significant differences had been found between the injured and uninjured leg in all isokinetic parameters in ACL/PCL patients. However, ACL/PCL patients had still shown significantly lower values of strength in relative isokinetic knee flexors (p = 0.0065) and extensors (p = 0.0171) compared to the CP. There were no differences between groups regarding absolute isokinetic strength and flexors/extensors ratio. There was statistically significant progress in IKDC 2000 (p = 0.0044) and Lysholm (p = 0.0044) scales prior to (44 and 60 points respectively) and after the reconstruction (61 for IKDC 2000 and 94 points for Lysholm).Conclusions
Although harvesting tendons of semitendinosus and/or gracilis from the healthy extremity diminishes muscle strength of knee flexors in comparison to the CP, flexor strength had improved. Statistically significant improvement of the knee extensor function may indicate that the recreation of joint mechanical stability is required for restoring normal muscle strength. Without restoring normal muscle function and strength, surgical intervention alone may not be sufficient enough to ensure expected improvement of the articular function. 相似文献72.
Bartosz Ditkowski Neil Holmes Joanna Rydzak Magdalena Donczew Martyna Bezulska Katarzyna Ginda Pawe? K?dzierski Jolanta Zakrzewska-Czerwińska Gabriella H. Kelemen Dagmara Jakimowicz 《Open biology》2013,3(3)
Prior to bacterial cell division, the ATP-dependent polymerization of the cytoskeletal protein, ParA, positions the newly replicated origin-proximal region of the chromosome by interacting with ParB complexes assembled on parS sites located close to the origin. During the formation of unigenomic spores from multi-genomic aerial hyphae compartments of Streptomyces coelicolor, ParA is developmentally triggered to form filaments along the hyphae; this promotes the accurate and synchronized segregation of tens of chromosomes into prespore compartments. Here, we show that in addition to being a segregation protein, ParA also interacts with the polarity protein, Scy, which is a component of the tip-organizing centre that controls tip growth. Scy recruits ParA to the hyphal tips and regulates ParA polymerization. These results are supported by the phenotype of a strain with a mutant form of ParA that uncouples ParA polymerization from Scy. We suggest that the ParA–Scy interaction coordinates the transition from hyphal elongation to sporulation. 相似文献
73.
74.
Aleksandra Lipka Marta Majewska Grzegorz Panasiewicz Martyna Bieniek-Kobuszewska Bozena Szafranska 《Functional & integrative genomics》2017,17(5):599-605
The pregnancy-associated glycoprotein-like family (PAG-L) is a large group of chorionic products, expressed in the pre-placental trophoblast and later in the post-implantational chorionic epithelium, and are involved in proper placenta development and embryo-maternal interaction in eutherians. This study describes identification of the PAG-L family in the genome of the Eurasian beaver (Castor fiber L.), named CfPAG-L. We identified 7657 bp of the CfPAG-L gDNA sequence (Acc. No. KX377932), encompassing nine exons (1–9) and eight introns (A–H). The length of the CfPAG-L exons (59–200 bp) was equivalently similar to the only known counterparts of bPAG1, bPAG2, and pPAG2. The length of the CfPAG-L introns ranged 288–1937 bp and was completely different from previously known PAG introns. The exonic CfPAG-L regions revealed 50.3–72.9% homology with equivalent segments of bPAG1 and pPAG2 structure. The intronic CfPAG-L regions alignments revealed a lack of homology. Within the entire CfPAG-L gene, 31 potential single nucleotide variants (SNV: 7 transversions and 24 transitions) were predicted. The identified exonic polymorphic loci did not affect the amino acid sequence of the CfPAG-L polypeptide precursor. This is the first report describing the CfPAG-L gene sequence, structural organization, and SNVs in the Eurasian beaver, one of the largest rodents. 相似文献
75.
The effect of heat shock, cisplatin, etoposide and quercetin on Hsp27 expression in human normal and tumour cells 总被引:5,自引:0,他引:5
Jakubowicz-Gil J Paduch R Gawron A Kandefer-Szerszeń M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2002,40(1):31-35
Heat shock protein 27 (Hsp27) belongs to the group of proteins called molecular chaperones protecting normal and tumour cells against many stressors such as hyperthermia, several commonly used chemotherapeutics as well as other apoptotic stimuli. Our study was designed to determine whether heat shock and drugs like cisplatin, etoposide and quercetin have an effect on the expression of heat shock protein 27 in tumour cells such as: HeLa (cervical cancer), Hep-2 (larynx cancer), A549 (lung cancer) and also in normal human skin fibroblasts (HSF) cultured in two-dimensional (2D) and three-dimensional (3D) conditions. Our results indicate that Hsp27 expression is drug- and cell-type specific and depends on the culture model as well. HeLa, Hep-2 and HSF cell cultured in 3D model appeared to be more resistant to stimulatory or inhibitory effects of the applied drugs than cells cultured in 2D model. Only A549 cells cultured in 3D culture model appeared to be more susceptible and reacted to drugs and heat treatment with increased Hsp27 expression. 相似文献
76.
Three tricyclic guanidine alkaloids, including 1,8a;8b,3a-didehydro-8β-hydroxyptilocaulin (1), 1,8a;8b,3a-didehydro-8-hydroxyptilocaulin (2) and mirabilin B (3), were identified from the marine sponge Monanchora unguifera. 1,8a;8b,3a-Didehydro-8-hydroxyptilocaulin (2) is a new stereoisomer of 1, the structure of which was elucidated by spectroscopic analysis, comparison of its spectral data with those of 1, and confirmed by X-ray analysis. Compounds 1 and 2 co-crystallized in an unusual perfect order and packed around an approximate inversion center. A mixture of 1 and 2 is active against the malaria parasite Plasmodium falciparum with an IC50 value of 3.8 μg/mL while mirabilin B (3) exhibited antifungal activity against Cryptococcus neoformans with an IC50 value of 7.0 μg/mL and antiprotozoal activity against Leishmania donovani with an IC50 value of 17 μg/mL. 相似文献
77.
Michelle Alexander Simon Y. W. Ho Martyna Molak Ross Barnett ?rjan Carlborg Ben Dorshorst Christa Honaker Francois Besnier Per Wahlberg Keith Dobney Paul Siegel Leif Andersson Greger Larson 《Biology letters》2015,11(10)
Mitochondrial genomes represent a valuable source of data for evolutionary research, but studies of their short-term evolution have typically been limited to invertebrates, humans and laboratory organisms. Here we present a detailed study of 12 mitochondrial genomes that span a total of 385 transmissions in a well-documented 50-generation pedigree in which two lineages of chickens were selected for low and high juvenile body weight. These data allowed us to test the hypothesis of time-dependent evolutionary rates and the assumption of strict maternal mitochondrial transmission, and to investigate the role of mitochondrial mutations in determining phenotype. The identification of a non-synonymous mutation in ND4L and a synonymous mutation in CYTB, both novel mutations in Gallus, allowed us to estimate a molecular rate of 3.13 × 10−7 mutations/site/year (95% confidence interval 3.75 × 10−8–1.12 × 10−6). This is substantially higher than avian rate estimates based upon fossil calibrations. Ascertaining which of the two novel mutations was present in an additional 49 individuals also revealed an instance of paternal inheritance of mtDNA. Lastly, an association analysis demonstrated that neither of the point mutations was strongly associated with the phenotypic differences between the two selection lines. Together, these observations reveal the highly dynamic nature of mitochondrial evolution over short time periods. 相似文献
78.
Sibrian-Vazquez M Jensen TJ Fronczek FR Hammer RP Vicente MG 《Bioconjugate chemistry》2005,16(4):852-863
The total syntheses of 14 porphyrin conjugates containing one to four positively charged amino acids and two distinct linkers are described. All conjugates were fully characterized using spectroscopic methods, and the X-ray structure of a porphyrin isothiocyanate precursor was obtained. In vitro studies using HEp2 cells show that these conjugates have low cytotoxicity (IC50 > 250 microM) and that the extent of their cellular uptake depends significantly on the number, nature, and sequence of amino acids in the peptide, and on the presence of a centrally chelated metal ion. Metal-free conjugates bearing three consecutive arginine residues accumulated the most within cells. On the other hand, the preferential sites of subcellular localization were found to be independent from the number, nature, and sequence of amino acids in the conjugate, the linker, and coordinated metal ion; it is suggested, based on theoretical calculations, that the peptides in these conjugates fold over the porphyrin macrocycle in order to maximize intramolecular hydrophobic interactions. 相似文献
79.
Alfredo Ortega Emma Maldonado Frank R. Fronczek Terry J. Delord Giacomo Chiari 《Phytochemistry》1985,24(8):1755-1760
Two novel sesquiterpene lactones were isolated from Verbesina seattonii. Their structures were elucidated as elemanolides possessing an intramolecular hemiacetal function on the basis of an extensive spectral analysis and crystal structure determination. 相似文献
80.
The symmetrical anionic and neutral dimers [H(TMSO)2]2trans-[{RuCl4(TMSO)}2](μ-pyz) (1), and mer-[{RuCl3(TMSO)2}2](μ-pyz) (2) were isolated by the reaction of [H(TMSO)] trans-[RuCl4(TMSO)2] and mer-[RuCl3(TMSO)3] with heterocyclic nitrogen donor ligand pyrazine (pyz) at room temperature. These complexes can be regarded as unprecedented examples in the general Creutz-Taube family of ruthenium dimers. Each ruthenium center in 1 and 2 has a coordination environment akin to that of known anionic and neutral monomeric Ru(III) complexes. Crystals of 1 · acetone are orange, needle like, space group , a=10.419(3) Å, b=10.539(3) Å, c=12.595(5) Å, α=69.837(16)°, β=69.968(15)°, γ=74.330(15)° and crystals of 2 · 4TMSO are orange prisms, trigonal, space group , a=33.971(5) Å, b=33.971(5) Å, c=12.210(2) Å, α=90°, β=90° and γ=120°. 相似文献