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排序方式: 共有475条查询结果,搜索用时 0 毫秒
81.
Raphaela Goldbach-Mansky Jennifer M Lee Joseph M Hoxworth David Smith II Paul Duray H Ralph Schumacher Jr Cheryl H Yarboro John Klippel David Kleiner Hani S El-Gabalawy 《Arthritis research & therapy》2000,2(2):145-9
Serum and synovial tissue expression of the matrix metalloproteinase (MMP)-2 and -9 and their molecular regulators, MMP-14 and TIMP-2 was examined in 28 patients with inflammatory early synovitis and 4 healthy volunteers and correlated with the presence of erosions in the patients. Immunohistological staining of MMP-2, MMP-14 and TIMP-2 localized to corresponding areas in the synovial lining layer and was almost absent in normal synovium. Patients with radiographic erosions had significantly higher levels of active MMP-2 than patients with no erosions, suggesting that activated MMP-2 levels in synovial tissue may be a marker for a more aggressive synovial lesion. 相似文献
82.
The hairpin ribozyme catalyses RNA cleavage by a mechanism utilizing its conformational flexibility during the docking of two independently folded internal loop domains A and B. Based on this mechanism, we designed hairpin ribozyme variants that can be induced or repressed by external effector oligonucleotides influencing the docking process. We incorporated a third domain C to assimilate alternate stable RNA motifs such as a pseudo-half-knot or an internal stem-loop structure. Small sequence changes in domain C allowed targeted switching of ribozyme activity: the same effector oligonucleotide can either serve as an inducer or repressor. The ribozymes were applied to trp leader mRNA, the RNA sequence tightly bound by l-tryptophan-activated trp-RNA-binding attenuation protein (TRAP). When domain C is complementary to this mRNA, ribozyme activity can be altered by annealing trp leader mRNA, then specifically reverted by its TRAP/tryptophan-mediated sequestration. This approach allows to precisely sense the activity status of a protein controlled by its metabolite molecule. 相似文献
83.
Litwin SB Mitra SK Von Colditz R Colditz JV Hamilton LB McManus T Jume'an HG Lazerson J 《Cardiovascular diseases》1981,8(3):364-371
The use of a fixed dosage schedule was compared with the use of activated clotting time (ACT) for determining heparin and protamine dosages during and after cardiopulmonary bypass disease. Use of the ACT resulted in a statistically significant increase in heparin dosage and a statistically significant reduction of postoperative blood loss. With ACT use, chest tubes were retained for a shorter period of time, and the incidence of serious postoperative hemorrhage was reduced from 44% to 18%. These results confirm the superiority of the ACT method for monitoring intraoperative anticoagulation in pediatric patients with congenital heart disease. 相似文献
84.
Summary Intracellular ethanol concentrations inSaccharomyces cerevisiae were measured using a high cell density fermentation technique which permits samples to be fixed for analysis in less than two seconds. No accumulation of intracellular ethanol was detected, regardless of the stage of fermentation. The technique eliminates artifacts associated with concentrating the cell sample and provides a reliable means for detecting whether other fermentation products accumulate intracellularly. 相似文献
85.
86.
Chondrogenic potential of adipose tissue-derived stromal cells in vitro and in vivo. 总被引:46,自引:0,他引:46
Geoffrey R Erickson Jeffrey M Gimble Dawn M Franklin Henry E Rice Hani Awad Farshid Guilak 《Biochemical and biophysical research communications》2002,290(2):763-769
Articular cartilage exhibits little intrinsic repair capacity, and new tissue engineering approaches are being developed to promote cartilage regeneration using cellular therapies. The goal of this study was to examine the chondrogenic potential of adipose tissue-derived stromal cells. Stromal cells were isolated from human subcutaneous adipose tissue obtained by liposuction and were expanded and grown in vitro with or without chondrogenic media in alginate culture. Adipose-derived stromal cells abundantly synthesized cartilage matrix molecules including collagen type II, VI, and chondroitin 4-sulfate. Alginate cell constructs grown in chondrogenic media for 2 weeks in vitro were then implanted subcutaneously in nude mice for 4 and 12 weeks. Immunohistochemical analysis of these samples showed significant production of cartilage matrix molecules. These findings document the ability of adipose tissue-derived stromal cells to produce characteristic cartilage matrix molecules in both in vitro and in vivo models, and suggest the potential of these cells in cartilage tissue engineering. 相似文献
87.
88.
M. W. Adlard B. M. Gordon T. Keshavarz C. Bucke M. D. Lilly A. T. Bull G. Holt 《Biotechnology Techniques》1991,5(2):121-126
Summary An HPLC procedure for the quantification of the precursor, intermediates, product, and degradation product of penicillin G fermentations is described. The method involves the use of an acetonitrile gradient and direct UV detection with a total run-time of 45 minutes including column regeneration. The technique can be exploited for on-line monitoring of penicillin G fermentations using defined or complex media. 相似文献
89.
Hanibal Hani Adamo Kerstin Str?mvall Maria Nilsson Sofia Halin Bergstr?m Anders Bergh 《PloS one》2015,10(11)
In order to grow, tumors need to induce supportive alterations in the tumor-bearing organ, by us named tumor instructed normal tissue (TINT) changes. We now examined if the nature and magnitude of these responses were related to tumor size and aggressiveness. Three different Dunning rat prostate tumor cells were implanted into the prostate of immune-competent rats; 1) fast growing and metastatic MatLyLu tumor cells 2) fast growing and poorly metastatic AT-1 tumor cells, and 3) slow growing and non-metastatic G tumor cells. All tumor types induced increases in macrophage, mast cell and vascular densities and in vascular cell-proliferation in the tumor-bearing prostate lobe compared to controls. These increases occurred in parallel with tumor growth. The most pronounced and rapid responses were seen in the prostate tissue surrounding MatLyLu tumors. They were, also when small, particularly effective in attracting macrophages and stimulating growth of not only micro-vessels but also small arteries and veins compared to the less aggressive AT-1 and G tumors. The nature and magnitude of tumor-induced changes in the tumor-bearing organ are related to tumor size but also to tumor aggressiveness. These findings, supported by previous observation in patient samples, suggest that one additional way to evaluate prostate tumor aggressiveness could be to monitor its effect on adjacent tissues. 相似文献
90.
Random amplified polymorphic DNA (RAPD) analysis was done on 32 isolates of Pseudomonas aeruginosa. These isolates were obtained from 22 patients who presented to the emergency room in a major medical center in Beirut, Lebanon,
during a 5-month period with the diagnosis of either unilateral or bilateral otitis externa. Patients had yellowish to greenish
discharge, moderate to severe external auditory canal swelling, moderate to severe pain, and periauricular cellulitis. None
of these patients had intrinsic predisposing factors. An ear swab was obtained from both ears of patients, cultured on trypticase
soy agar. P. aeruginosa was identified on the basis of pyocyanine production and API identification kits. RAPD analysis was done by using two primers
(10 mer and 21 mer primers) and appropriate PCR conditions on extracted DNA. Our data have shown 23 RAPD patterns (A–W) distributed
among the 32 P. aeruginosa isolates. RAPD patterns were reproducible. Twenty of 32 isolates were recovered from 10 patients with bilateral otitis externa.
The remaining 12 of 32 isolates were recovered from 12 different patients with unilateral otitis externa. Eleven RAPD patterns
(A,B,C,D,E,F,H,I,R,U,V) were associated with severe clinical symptoms, including severe pain, severe external auditory canal
swelling, periauricular cellulitis, and a yellowish discharge. The remaining RAPD patterns were not associated with severe
infections. This denotes a possible association between certain genotypes and severity of symptoms.
Received: 6 July 2000 / Accepted: 5 September 2000 相似文献