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991.
Ira J. Condit 《Economic botany》1948,2(4):403-418
In 1947 six varieties of Old World figs, cultivated on about 50,000 acres in California, produced 30,500 tons of dried figs, the largest crop on record for the State. 相似文献
992.
Juan Liao Humberto B. Jijon Ira R. Kim Gautam Goel Aivi Doan Harry Sokol Hermann Bauer Bernhard G. Herrmann Kara G. Lassen Ramnik J. Xavier 《PloS one》2014,9(9)
The pathogenesis of complex diseases, such as type 1 diabetes (T1D), derives from interactions between host genetics and environmental factors. Previous studies have suggested that viral infection plays a significant role in initiation of T1D in genetically predisposed individuals. T1D susceptibility loci may therefore be enriched in previously uncharacterized genes functioning in antiviral defense pathways. To identify genes involved in antiviral immunity, we performed an image-based high-throughput genetic screen using short hairpin RNAs (shRNAs) against 161 genes within T1D susceptibility loci. RAW 264.7 cells transduced with shRNAs were infected with GFP-expressing herpes simplex virus type 1 (HSV-1) and fluorescent microscopy was performed to assess the viral infectivity by fluorescence reporter activity. Of the 14 candidates identified with high confidence, two candidates were selected for further investigation, Il27 and Tagap. Administration of recombinant IL-27 during viral infection was found to act synergistically with interferon gamma (IFN-γ) to activate expression of type I IFNs and proinflammatory cytokines, and to enhance the activities of interferon regulatory factor 3 (IRF3). Consistent with a role in antiviral immunity, Tagap-deficient macrophages demonstrated increased viral replication, reduced expression of proinflammatory chemokines and cytokines, and decreased production of IFN-β. Taken together, our unbiased loss-of-function genetic screen identifies genes that play a role in host antiviral immunity and delineates roles for IL-27 and Tagap in the production of antiviral cytokines. 相似文献
993.
Infrared and Raman spectra were obtained for the 1690–1770 cm?1 carbonyl stretching mode region for 1,2-dipalmitoyl phosphatidylcholine (DPPC) bilayers in the anhydrous, partially hydrated and completely hydrated states. Spectral features at approx. 1740 and 1721 cm?1 are assigned to CO stretching modes associated with the 1- and 2-chain carbonyl groups, respectively. Splittings of the primary transitions at 1743, 1738, ~1731 and ~1721 cm?1 are attributed to rotational isomers involving the entire chain. Hydrogen bond formation between the fatty acid carbonyl and 3βOH cholesterol groups was investigated for anhydrous DPPC bilayers. Examination of frequencies, intensities and half-widths of the carbonyl bands indicates that no hydrogen bonding occurs at either of the two carbonyl sites. However, the addition of cholesterol to completely hydrated DPPC dispersions reduces the conformational inequivalence between the two fatty acid carbonyl groups by specifically perturbing the 2-chain. For cholesterol containing systems the carbonyl stretching mode transitions were also used to monitor lattice effects within the interface region as water binds to the bilayer head groups. Specifically, the addition of approx. 2 molecules of water per lipid molecule orders the lipid lattice and increases the bilayer packing density, while the subsequent addition of 4 molecules of water per lipid molecule releases the packing constraints within the interface region and thereby decreases the packing density. 相似文献
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995.
Christopher J. Traynham Steve R. Roof Honglan Wang Robert A. Prosak Lifei Tang Serge Viatchenko-Karpinski Hsiang-Ting Ho Ira O. Racoma Dominic J. Catalano Xin Huang Yongbin Han Shang-U Kim Sandor Gyorke George E. Billman Frederick A. Villamena Mark T. Ziolo 《PloS one》2012,7(12)
Nitric oxide (NO) and superoxide (O2
−) are important cardiac signaling molecules that regulate myocyte contraction. For appropriate regulation, NO and O2
.− must exist at defined levels. Unfortunately, the NO and O2
.− levels are altered in many cardiomyopathies (heart failure, ischemia, hypertrophy, etc.) leading to contractile dysfunction and adverse remodeling. Hence, rescuing the nitroso-redox levels is a potential therapeutic strategy. Nitrone spin traps have been shown to scavenge O2
.− while releasing NO as a reaction byproduct; and we synthesized a novel, cell permeable nitrone, 2–2–3,4-dihydro-2H-pyrrole 1-oxide (EMEPO). We hypothesized that EMEPO would improve contractile function in myocytes with altered nitroso-redox levels. Ventricular myocytes were isolated from wildtype (C57Bl/6) and NOS1 knockout (NOS1−/−) mice, a known model of NO/O2
.− imbalance, and incubated with EMEPO. EMEPO significantly reduced O2
.− (lucigenin-enhanced chemiluminescence) and elevated NO (DAF-FM diacetate) levels in NOS1−/− myocytes. Furthermore, EMEPO increased NOS1−/− myocyte basal contraction (Ca2+ transients, Fluo-4AM; shortening, video-edge detection), the force-frequency response and the contractile response to β-adrenergic stimulation. EMEPO had no effect in wildtype myocytes. EMEPO also increased ryanodine receptor activity (sarcoplasmic reticulum Ca2+ leak/load relationship) and phospholamban Serine16 phosphorylation (Western blot). We also repeated our functional experiments in a canine post-myocardial infarction model and observed similar results to those seen in NOS1−/− myocytes. In conclusion, EMEPO improved contractile function in myocytes experiencing an imbalance of their nitroso-redox levels. The concurrent restoration of NO and O2
.− levels may have therapeutic potential in the treatment of various cardiomyopathies. 相似文献
996.
997.
Kavita P. Ahluwalia Bin Cheng Philip K. Josephs Evanthia Lalla Ira B. Lamster 《Gerodontology》2010,27(2):96-103
doi:10.1111/j.1741‐2358.2009.00311.x Oral disease experience of older adults seeking oral health services Objective: The objective of this investigation was to describe the dental disease (dental caries and alveolar bone loss) experience in a sample of community‐dwelling older adults who regularly utilize dental services in New York City. Background: Public financing for dental care directed at older adults in the United States is minimal. Improved preventive methods, primarily the use of fluorides, have resulted in declines in tooth loss, and concomitant increase in risk for dental diseases among older adults. While the oral disease burden in institutionalized elderly and those unable to access services is well‐documented, the dental care needs of older adults who access dental services are not well documented. Materials and Methods: Radiographic and record review were used to determine prevalence of dental caries, alveolar bone loss, frequency of service utilization, and medical status in this cross‐sectional investigation of a sample of older adults (N = 200) using dental services at Columbia University College of Dental Medicine. Results: Only 9% of the sample was completely edentulous, the mean DMFT was 19.9 and mean alveolar bone loss was 3.6 mm. Missing and Decayed Teeth accounted for 57.8% and 6.5% of the total caries burden respectively. Missing Teeth and alveolar bone loss increased with increasing age, but there was no increase in Decayed Teeth. Conclusions: While access to and utilization of dental services may result in improved tooth retention, older adults who use dental services continue to have dental care needs, especially periodontal care needs. 相似文献
998.
999.
1000.
William J Bonney Scott R Ceresnak Shetty Ira Allan Hordof Leonardo Liberman 《Indian pacing and electrophysiology journal》2009,9(6):355-359
Primary tumors of the heart are rare, but they are often associated with refractory arrhythmias. Vascular tumors of the heart comprise a small minority of primary cardiac tumors. In patients with structurally normal hearts, ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) can be sensitive to adenosine, vagal maneuvers, and calcium channel blockers. In this report, we describe a case of ventricular tachycardia originating from within a hemangioma in the RVOT that was ultimately controlled with verapamil. 相似文献