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131.
Isolation and composition of the extracellular slime made by coagulase-negative staphylococci in a chemically defined medium 总被引:6,自引:0,他引:6
Slime isolated after growth of four strains of coagulase-negative staphylococci on chemically defined medium plus agar was rich in galactose. However, when sterile agar plates were extracted with saline, high-molecular-weight material with similar properties was obtained that also was galactose-rich. Most of the dry weight attributed to slime, and probably all the galactose, originated from agar. Slime isolated by gel and ion-exchange chromatography from liquid culture in the same medium contained glycerol phosphate, glucose (no galactose), glucosamine, alanine, uronate, an unidentified component, and protein. Separation of protein from carbohydrate was achieved by affinity chromatography. [14C]glucose in the medium labeled the carbohydrate polymer; [14C]amino acids chiefly labeled extracellular proteins. Slime from bacteria grown on medium solidified with silica gel or on dialysis membrane above an agar surface showed essentially the same composition and behavior after purification as the material isolated from liquid culture. 相似文献
132.
Presente A Boyles RS Serway CN de Belle JS Andres AJ 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(6):1764-1768
A role for Notch in the elaboration of existing neural processes is emerging that is distinct from the increasingly well understood function of this gene in binary cell-fate decisions. Several research groups, by using a variety of organisms, have shown that Notch is important in the development of neural ultrastructure. Simultaneously, Presenilin (Psn) was identified both as a key mediator of Notch signaling and as a site of genetic lesions that cause early-onset Alzheimer's disease. Here we demonstrate that Notch loss of function produces memory deficits in Drosophila melanogaster. The effects are specific to long-term memory, which is thought to depend on ultrastructural remodeling. We propose that Notch plays an important role in the neural plasticity underlying consolidated memory. 相似文献
133.
Savage KJ Harris NL Vose JM Ullrich F Jaffe ES Connors JM Rimsza L Pileri SA Chhanabhai M Gascoyne RD Armitage JO Weisenburger DD;International Peripheral T-Cell Lymphoma Project 《Blood》2008,111(12):5496-5504
The International Peripheral T-Cell Lymphoma Project is a collaborative effort designed to gain better understanding of peripheral T-cell and natural killer (NK)/T-cell lymphomas (PTCLs). A total of 22 institutions in North America, Europe, and Asia submitted clinical and pathologic information on PTCLs diagnosed and treated at their respective centers. Of the 1314 eligible patients, 181 had anaplastic large-cell lymphoma (ALCL; 13.8%) on consensus review: One hundred fifty-nine had systemic ALCL (12.1%) and 22 had primary cutaneous ALCL (1.7%). Patients with anaplastic lymphoma kinase–positive (ALK+) ALCL had a superior outcome compared with those with ALK– ALCL (5-year failure-free survival [FFS], 60% vs 36%; P = .015; 5-year overall survival [OS], 70% vs 49%; P = .016). However, contrary to prior reports, the 5-year FFS (36% vs 20%; P = .012) and OS (49% vs 32%; P = .032) were superior for ALK– ALCL compared with PTCL, not otherwise specified (PTCL-NOS). Patients with primary cutaneous ALCL had a very favorable 5-year OS (90%), but with a propensity to relapse (5-year FFS, 55%). In summary, ALK– ALCL should continue to be separated from both ALK+ ALCL and PTCL-NOS. Although the prognosis of ALK– ALCL appears to be better than that for PTCL-NOS, it is still unsatisfactory and better therapies are needed. Primary cutaneous ALCL is associated with an indolent course. 相似文献
134.
The yeasts Rho1p and Pkc1p regulate the transport of chitin synthase III (Chs3p) from internal stores to the plasma membrane
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Valdivia RH Schekman R 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(18):10287-10292
During cell stress, Saccharomyces cerevisiae increases the synthesis of chitin and glucans to strengthen and repair the cell wall. In this study, we show that under conditions of cell stress, the steady-state localization of chitin synthase III (Chs3p) shifts from internal stores (chitosomes) to the plasma membrane (PM). This redistribution occurs rapidly and requires the activators of the cell wall stress response signaling pathway, the G protein Rho1p, and the protein kinase Pkc1p, but not the cell integrity response mitogen-activated protein kinase cascade. Furthermore, expression of activated forms of Rho1p or Pkc1p, in the absence of cell stress, is sufficient to redistribute Chs3p to the PM. In cells deficient for both the clathrin adaptor complex 1 and Chs6p, where Chs3p is transported to the PM by an alternative bypass pathway, cell wall stress did not cause mobilization of Chs3p, suggesting that Rho1p/Pkc1p regulate Chs3p exit from the trans-Golgi network. The mobilization of an intracellular reservoir of Chs3p presents a novel opportunity to investigate the genetic basis of regulated vesicular traffic. 相似文献
135.
136.
Anthony Iacco Adewunmi AdeyemoThomas Riggs M.D. Ph.D. Randy Janczyk M.D. 《American journal of surgery》2014
Background
Complex ventral hernias remain a challenge. We present a study evaluating outcomes of complex ventral hernia repair using human-derived acellular dermal matrix (AlloDerm) and porcine-derived acellular dermal sheet (Permacol).Methods
A retrospective review of 251 patients undergoing complex hernia repair was performed. Primary outcome was hernia recurrence; and secondary outcomes included early and late complications and mortality.Results
Recurrence for Permacol versus AlloDerm was 32% versus 47% (P = .02). There was a difference in early complications (48% vs 30%, P = .007) and also late complications (30% vs 21%, P = .16) of Permacol versus AlloDerm. Overall survival was 85% for the Permacol group versus 78% for the AlloDerm group (P = .23). Recurrence for Permacol versus AlloDerm for underlay technique was 19% versus 22% and that for bridging technique was 44% versus 57%.Conclusion
There exists a high complication rate from both Permacol and AlloDerm in complex ventral hernia repair especially when used as a fascial bridge. 相似文献137.
Lyndon G. Amorin-Woods Randy W. Beck Gregory F. Parkin-Smith James Lougheed Alexandra P. Bremner 《The Journal of the Canadian Chiropractic Association》2014,58(3):220-237
Aim:
To determine adherence to clinical practice guidelines in the medical, physiotherapy and chiropractic professions for acute and subacute mechanical low back pain through best-evidence synthesis of the healthcare literature.Methods:
A structured best-evidence synthesis of the relevant literature through a literature search of relevant databases for peer-reviewed papers on adherence to clinical practice guidelines from 1995 to 2013. Inclusion of papers was based on selection criteria and appraisal by two reviewers who independently applied a modified Downs & Black appraisal tool. The appraised papers were summarized in tabular form and analysed by the authors.Results:
The literature search retrieved 23 potentially relevant papers that were evaluated for methodological quality, of which 11 studies met the inclusion criteria. The main finding was that no profession in the study consistently attained an overall high concordance rating. Of the three professions examined, 73% of chiropractors adhered to current clinical practice guidelines, followed by physiotherapists (62%) and then medical practitioners (52%).Conclusions:
This review showed that quality papers in this area of research are very limited. Notwithstanding, chiropractors appear to adhere to clinical practice guidelines more so than physiotherapists and medical practitioners, although there is scope for improvement across all three professions. 相似文献138.
Abdallah El Sabbagh Vishal G. Patel Omar M. Jeroudi Tesfaldet T. Michael Mohammed E. Alomar Owen Mogabgab Eric Fuh Michele Roesle Bavana V. Rangan Shuaib Abdullah Jeffrey L. Hastings Jerrold Grodin Dharam J. Kumbhani Dimitrios Alexopoulos Panayotis Fasseas Subhash Banerjee Emmanouil S. Brilakis 《International journal of cardiology》2014
Background
The efficacy and safety profile of retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. We sought to perform a weighted meta-analysis of the success and complication rates of retrograde CTO PCI.Methods
We conducted a meta-analysis of 26 studies published between 2006 and April 2013 reporting in-hospital outcomes of retrograde CTO PCI. Data on procedural success, frequency of death, emergent coronary artery bypass graft surgery (CABG), stroke, myocardial infarction (MI), perforation, tamponade, stent thrombosis, major vascular or bleeding events, contrast nephropathy, and radiation skin injury were collected.Results
A total of 26 studies with 3482 patients and 3493 target CTO lesions were included. Primary retrograde CTO PCI was attempted in 52.4%. Pooled estimates of outcomes were as follows: procedural success 83.3% [95% confidence interval (CI): 79.0% to 87.7%]; death 0.7% (95% CI: 0.5% to 1.2%); urgent CABG 0.7% (95% CI: 0.4% to 1.2%); tamponade 1.4% (95% CI: 1.0% to 2.2%); collateral perforation 6.9% (95% CI: 4.6% to 10.4%); coronary perforation 4.3% (95% CI: 1.2% to 15.4%); donor vessel dissection 2% (95% CI: 0.9% to 4.5%); stroke 0.5% (95% CI: 0.2% to 1.0%); MI 3.1% (95% CI: 0.2% to 5.0%); Q wave MI 0.6% (95% CI: 0.4% to 1.1%); vascular access complications 2% (95% CI: 0.9% to 4.5%); contrast nephropathy 1.8% (95% CI: 0.8% to 3.7%); and wire fracture and equipment entrapment 1.2% (95% CI: 0.6% to 2.5%).Conclusions
Retrograde CTO PCI is associated with high procedural success rate and acceptable risk for procedural complications. 相似文献139.