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231.
Cho MJ Pestina TI Steward SA Jackson CW Kent Gartner T 《Biochemical and biophysical research communications》2002,292(4):916-921
The work presented here demonstrates that platelets from mice lacking LAT (linker for the activation of T cells) show reversible aggregation in response to concentrations of collagen that cause TxA2/ADP-dependent irreversible aggregation of control platelets. The aggregation defect of the LAT-deficient platelets was shown to be the result of almost no TxA2 production and significantly diminished ADP secretion. In contrast, the LAT deficiency does not affect aggregation induced by high concentrations of collagen because that aggregation is not dependent on TxA2 and/or ADP. Even though ADP and TxA2 provide amplification signals for platelet activation in response to low concentrations of collagen, LAT-deficient platelets hyperaggregate to low levels of U46619, a TxA2 analog, or ADP. Though the mechanism(s) of costimulatory signals by collagen, ADP, and TxA2 remains unidentified, it is clear that LAT plays a positive role in collagen-induced, TxA2/ADP-dependent aggregation, and a negative role in TxA2 or ADP-induced platelet aggregation. 相似文献
232.
Champy miniplates have been used in the treatment of craniofacial fractures and in osteotomies for correction of posttraumatic deformities, congenital craniofacial deformities, and secondary bony deformities due to pathologies such as hemangioma and neurofibroma. An additional use has been to stabilize free and vascularized bone grafts. The total number of cases reviewed were 50 (25 acute trauma, 4 vascularized mandible reconstruction, and 21 osteotomies of varied types). There were three infections, two in mandibular fractures that were comminuted and compound into the mouth and one in a compound comminuted fracture of the frontal and maxillary area that was judged to be infected when the plate was placed in position. Two plates have been obvious under the skin. No patient has requested plate removal. The advantages of plating in selected cases are decreased operating time, rigid fixation at surgery, good fixation of bone grafts, and the ability to remove intermaxillary fixation in children at the end of the procedure or within the first few postoperative days. 相似文献
233.
Nicolas Tavaglione Angela K. Martin Nathalie Mezger Sophie Durieux‐Paillard Anne François Yves Jackson Samia A. Hurst 《Bioethics》2015,29(2):98-107
In the literature on medical ethics, it is generally admitted that vulnerable persons or groups deserve special attention, care or protection. One can define vulnerable persons as those having a greater likelihood of being wronged – that is, of being denied adequate satisfaction of certain legitimate claims. The conjunction of these two points entails what we call the Special Protection Thesis. It asserts that persons with a greater likelihood of being denied adequate satisfaction of their legitimate claims deserve special attention, care or protection. Such a thesis remains vague, however, as long as we do not know what legitimate claims are. This article aims at dispelling this vagueness by exploring what claims we have in relation to health care – thus fleshing out a claim‐based conception of vulnerability. We argue that the Special Protection Thesis must be enriched as follows: If individual or group X has a greater likelihood of being denied adequate satisfaction of some of their legitimate claims to (i) physical integrity, (ii) autonomy, (iii) freedom, (iv) social provision, (v) impartial quality of government, (vi) social bases of self‐respect or (vii) communal belonging, then X deserves special attention, care or protection. With this improved understanding of vulnerability, vulnerability talk in healthcare ethics can escape vagueness and serve as an adequate basis for practice. 相似文献
234.
Initial gene vector dosing for studying symptomatology of amyotrophic lateral sclerosis in non‐human primates 下载免费PDF全文
235.
Jackson RW LaPorte MG Herbertz T Draper TL Gaboury JA Rippin SR Patel R Chunduru SK Benetatos CA Young DC Burns CJ Condon SM 《Bioorganic & medicinal chemistry letters》2011,21(11):3227-3231
We describe the structure-activity relationship of the C7-position of pyrano[3,4-b]indole-based inhibitors of HCV NS5B polymerase. Further exploration of the allosteric binding site led to the discovery of the significantly more potent compounds 13 and 14. 相似文献
236.
Wellman A Eckert DJ Jordan AS Edwards BA Passaglia CL Jackson AC Gautam S Owens RL Malhotra A White DP 《Journal of applied physiology (Bethesda, Md. : 1985)》2011,110(6):1627-1637
There is not a clinically available technique for measuring the physiological traits causing obstructive sleep apnea (OSA). Therefore, it is often difficult to determine why an individual has OSA or to what extent the various traits contribute to the development of OSA. In this study, we present a noninvasive method for measuring four important physiological traits causing OSA: 1) pharyngeal anatomy/collapsibility, 2) ventilatory control system gain (loop gain), 3) the ability of the upper airway to dilate/stiffen in response to an increase in ventilatory drive, and 4) arousal threshold. These variables are measured using a single maneuver in which continuous positive airway pressure (CPAP) is dropped from an optimum to various suboptimum pressures for 3- to 5-min intervals during sleep. Each individual's set of traits is entered into a physiological model of OSA that graphically illustrates the relative importance of each trait in that individual. Results from 14 subjects (10 with OSA) are described. Repeatability measurements from separate nights are also presented for four subjects. The measurements and model illustrate the multifactorial nature of OSA pathogenesis and how, in some individuals, small adjustments of one or another trait (which might be achievable with non-CPAP agents) could potentially treat OSA. This technique could conceivably be used clinically to define a patient's physiology and guide therapy based on the traits. 相似文献
237.
ProServer: a simple, extensible Perl DAS server 总被引:1,自引:0,他引:1
Finn RD Stalker JW Jackson DK Kulesha E Clements J Pettett R 《Bioinformatics (Oxford, England)》2007,23(12):1568-1570
SUMMARY: The increasing size and complexity of biological databases has led to a growing trend to federate rather than duplicate them. In order to share data between federated databases, protocols for the exchange mechanism must be developed. One such data exchange protocol that is widely used is the Distributed Annotation System (DAS). For example, DAS has enabled small experimental groups to integrate their data into the Ensembl genome browser. We have developed ProServer, a simple, lightweight, Perl-based DAS server that does not depend on a separate HTTP server. The ProServer package is easily extensible, allowing data to be served from almost any underlying data model. Recent additions to the DAS protocol have enabled both structure and alignment (sequence and structural) data to be exchanged. ProServer allows both of these data types to be served. AVAILABILITY: ProServer can be downloaded from http://www.sanger.ac.uk/proserver/ or CPAN http://search.cpan.org/~rpettett/. Details on the system requirements and installation of ProServer can be found at http://www.sanger.ac.uk/proserver/. 相似文献
238.
Various measurements are still considered to be important for making decisions regarding the approach in reduction mammaplasty, even though the vast majority of techniques used are based on an inferior pedicle. This study was performed to analyze the variability of the suprasternal notch-to-nipple and nipple-to-inframammary fold distance measurements when using the inferior pedicle technique. In 92 patients, 184 breasts having various volumes were measured preoperatively, and the variability of the measurements of the suprasternal notch-to-nipple and nipple-to-inframammary fold distance was analyzed. The values of the distance from the suprasternal notch to nipple were dispersed over a wide range with a trimodal distribution, with peaks at the intervals of 23 to 27 cm, 28 to 33 cm, and 34 to 45 cm. In contrast, the values of the nipple-to-inframammary fold distance showed a normal distribution pattern, with the peak at 14 cm. The distance from the suprasternal notch to nipple has a fair relationship to the inframammary fold-to-nipple distance, the latter being concentrated in a smaller range (r = 0.51). The former is often used to decide whether a free-nipple graft should be performed. However, the relative consistency of the latter measurement has led to the conclusion that the free-nipple graft technique need never be considered. 相似文献
239.
Caili Bi Fang Chen Lisa Jackson Bikram S. Gill Wanlong Li 《Plant Molecular Biology Reporter》2011,29(1):149-161
As a major component of the cell wall, lignin plays an important role in plant development and defense response to pathogens,
but negatively impacts biomass processability for biofuels. Silencing the target lignin genes for greater biomass processability
should not significantly affect plant development and biomass yield but also must not compromise disease resistance. Here,
we report experiments to identify a set of lignin genes that may be silenced without compromising disease resistance. We profiled
the expression of 32 lignin biosynthetic candidate genes by qRT-PCR in 17 wheat tissues collected at three developmental stages.
Twenty-one genes were expressed at a much higher level in stems compared to sheaths and leaf blades. Expression of seven these
genes significantly correlated with lignin content. The co-expression patterns indicated that these 21 genes are under strong
developmental regulation and may play a role in lignin biosynthesis. Profiling gene expression of same tissues challenged
by two fungal pathogens, Fusarium graminearum and Puccina triticina indicated that expression of 17 genes was induced by F. graminearum. Only PAL1, a non-developmental-regulated gene, was induced by P. triticina. Thus, lignin biosynthetic pathway overlaps defense response to F. graminearum. Based on these criteria, 17 genes, F5H1, F5H2, 4CL2, CCR2, COMT1, and COMT2 in particular that do not overlap with disease resistance pathway, may be the targets for downregulation. 相似文献
240.
Maria D. Jackson Marshall K. Tulloch-Reid Norma McFarlane-Anderson Alexis Watson Vestra Seers Franklyn I. Bennett Brian Egleston Camille Ragin 《Genes & nutrition》2013,8(2):199-207
Little is known about the role of folate and polymorphisms associated with folate metabolism on prostate cancer risk in populations of African origin. We examined the relationship between serum folate and prostate cancer and whether any association was modified by genetic polymorphisms for folate metabolism. The study was case–control in design and consisted of 218 men 40–80 years old with newly diagnosed, histologically confirmed prostate cancer and 236 cancer-free men attending the same urology clinics in Jamaica, March 2005–July 2007. Serum folate was measured by an immunoassay method and genomic DNA evaluated for MTHR (C677T and A1298C), MTRR A66G, and MTR A2756G polymorphisms. Mean serum folate concentration was higher among cases (12.3 ± 4.1 nmol/L) than controls (9.7 ± 4.2 nmol/L). Serum folate concentration showed a positive association with prostate cancer (OR, 4.41; CI, 2.52–7.72 per 10 nmol/L) regardless of grade. No interactions were observed between genotype and folate concentration, but a weak gene effect was observed for MTHFR A1298C and low-grade prostate cancer. Larger studies to investigate the role of gene–gene/gene–diet interactions in Black men are needed. 相似文献