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991.
MJ Eppinger ML Jones GM Deeb SF Bolling PA Ward 《Canadian Metallurgical Quarterly》1995,58(6):713-718
Using a rat lung model, we sought to characterize the time course for ischemia-reperfusion injury and the role of neutrophils in the development of injury. Adult male Long-Evans rats underwent left thoracotomy with dissection and clamping of the left pulmonary artery, bronchus, and vein for 90 min, resulting in complete left lung ischemia. The lungs were then ventilated and reperfused for up to 4 hr. Time-matched sham animals underwent the identical thoracotomy and hilar dissection, but the lungs were not rendered ischemic. Using vascular permeability of 125I-labeled bovine serum albumin as a measure of reperfusion injury, a bimodal pattern of injury was observed. Compared to sham controls, animals undergoing ischemia-reperfusion demonstrated a significant early phase of lung injury at 30 min of reperfusion (P < 0.0001), followed by partial recovery. A second peak of lung injury was noted after 4 hr of reperfusion (P < 0.001). Myeloperoxidase activity in reperfused lung tissue, a measure of neutrophil sequestration, increased during the reperfusion time course. To determine the role of neutrophils in the development of lung reperfusion injury, additional animals undergoing the identical ischemia-reperfusion protocol received either rabbit anti-rat neutrophil serum or preimmune serum the day prior to operation. Profound neutropenia (< 75/mm3 blood) was confirmed by differential leukocyte counts. Neutropenia had no protective effect against microvascular permeability at 30 min of reperfusion, but there was a significant reduction in lung injury at 4 hr (P < 0.005). We conclude that, during lung ischemia-reperfusion, there is a bimodal pattern of injury, consisting of both neutrophil-independent and neutrophil-mediated events. 相似文献
992.
RA McKay LL Cummins MJ Graham EA Lesnik SR Owens M Winniman NM Dean 《Canadian Metallurgical Quarterly》1996,24(3):411-417
We have previously described the characterization of a 20mer phosphorothioate oligodeoxynucleotide (ISIS 4189) which inhibits murine protein kinase C-alpha (PKC-alpha) gene expression, both in vitro and in vivo. In an effort to increase the antisense activity of this oligonucleotide, 2'-O-propyl modifications have been incorporated into the 5'- and 3'-ends of the oligonucleotide, with the eight central bases left as phosphorothioate oligodeoxynucleotides. Hybridization analysis demonstrated that these modifications increased affinity by approximately 8 and 6 degrees C per oligonucleotide for the phosphodiester (ISIS 7815) and phosphorothioate (ISIS 7817) respectively when hybridized to an RNA complement. In addition, 2'-O-propyl incorporation greatly enhanced the nuclease resistance of the oligonucleotides to snake venom phosphodiesterase or intracellular nucleases in vivo. The increase in affinity and nuclease stability of ISIS 7817 resulted in a 5-fold increase in the ability of the oligonucleotide to inhibit PKC-alpha gene expression in murine C127 cells, as compared with the parent phosphorothioate oligodeoxynucleotide. Thus an RNase H-dependent phosphorothioate oligodeoxynucleotide can be modified as a 2'-O-propyl 'chimeric' oligonucleotide to provide a significant increase in antisense activity in cell culture. 相似文献
993.
As children and adults with developmental disabilities and special health care needs are integrated into home, school, and community life, nurses are being required to provide leadership, advocacy, and training in community settings to a much greater extent than in the past. To assess the school and community need for formal graduate preparation for nurses who work with individuals with developmental disabilities and/or special health care needs, 25 nurses in leadership positions representing urban and rural health agencies throughout Minnesota took part in a 5-hour focus group discussion. Analysis of data summarized from this process shows five features of the recommended curriculum necessary for advanced practitioners in this specialty area: (a) discipline-specific core competencies, (b) discipline-specific specialty competencies, (c) genetic competencies not specific to nursing but necessary to function in nursing roles, (d) interdisciplinary and intradisciplinary learning experiences, and (e) clinical experiences with preceptors. The authors recommend the development of interdisciplinary graduate programs designed to prepare nurses to assume leadership roles in school health, public health, home health care, and systems management that will affect public policy and, ultimately, promote change in the systems charged with responsibility to serve this population. 相似文献
994.
PA Greenberger YK Odeh MC Frederiksen AJ Atkinson 《Canadian Metallurgical Quarterly》1993,53(3):324-328
A possible interaction of salmon-calcitonin with opioid systems was studied in isolated tissues. Neurogenic contractions were elicited by electrical stimulation in guinea-pig ileum myenteric plexus-longitudinal muscle strips, rabbit vas deferens and mouse vas deferens. Bremazocine inhibited neurogenic contractions in all three tissues (presumably through kappa-receptors) [D-Pen2, D-Pen5]enkephalin and [Met5]enkephalin inhibited contractions in mouse vas deferens (presumably through delta-receptors), and [D-Ala2, N-Me-Phe4, Gly5-ol]enkephalin (DAMGO) inhibited contractions in guinea-pig ileum and mouse vas deferens (presumably through mu-receptors). All inhibitory effects were concentration-dependent. Salmon-calcitonin 0.1 IU/ml increased the effect of bremazocine in guinea-pig ileum and rabbit vas deferens and also increased the effects of [D-Pen2, D-Pen5]enkephalin and [Met5]enkephalin in mouse vas deferens. In contrast, salmon-calcitonin up to 0.4 IU/ml did not change the effect of bremazocine in mouse vas deferens and the effect of DAMGO in guinea-pig ileum and mouse vas deferens. It is concluded that salmon-calcitonin enhances agonist effects at opioid kappa- and delta- but not at opioid mu-receptors. The level of this interaction remains to be elucidated. The interaction may be the basis of the analgesic effect of salmon-calcitonin in vivo. 相似文献
995.
Sanjay B. Joshi Walter C. Hoberecht Jason Lee Richard A. Wysk Dean C. Barrick 《IIE Transactions》1994,26(4):2-18
This paper discusses a Group Technology (GT) and Computer Aided Process Planning (CAPP) installation at JLG Industries, Inc., an international manufacturer and marketer of specialized hydraulic machinery. An efficient architecture for the design, development and implementation of the system is presented along with system design requirements and characteristics. A GT software shell is described, and for the architecture that is defined, a formal model of the process planning system is developed. The model is used as the basis for the creation of a generic semi-generative CAPP system. Implementation of the model along with experience with the system is included. Run time examples of the system are provided to illustrate the features of the system. 相似文献
996.
997.
A new class of so-called pseudo-starshaped polygons is introduced. A polygon is pseudo-star-shaped if there exists a point from which the whole interior of the polygon can be seen, provided it is possible to see through single edges. We show that the class of pseudo-star-shaped polygons unifies and generalizes the well-known classes of convex, monotone and pseudostar-sphaped polygons. We give algorithms for testing whether a polygon is pseudostar-shaped from a given point in linear time, and for constructing all regions from which the polygon is pseudo-star-shaped in quadratic time. We show the latter algorithm to be worst-case optimal. Also, we give efficient algorithms solving standard geometrical problems such as point-location and triangulation for pseudo-starshaped polygons.A preliminary version of this paper has been presented at the 24 th Allerton Conference on Communication, Control and Computing, Monticello, Ill, October 1986Research for this paper was done while the author was at Carleton UniversityResearch for this paper was done in part while the author was visiting Carleton UniversityThis research was supported in part by NSERC and by Carleton University 相似文献
998.
999.
A system has been developed for extending the lifetime of an implantable biotelemeter (or potentially a variety of implantable electronic devices), first by recharging implanted nickel cadmium (NiCd) batteries via radio frequency power transmitted from an external portable source, and second by providing on/off electronic power switching which, when activated externally, allows for shutdown of the biotelemeter when not required and subsequent powering up when needed. The battery pack, which has been successfully evaluated in the dog, uses four sealed NiCd 100 mA ·h, 1.25 V dc cells which can be "quick charged" at 40 mA in 2.5 h. Higher or lower charge rates are available and the charging rate is telemetered for continuous battery status indication. The system has been designed to charge the implanted batteries through 13 mm tissue thickness, using 50 mm diameter transmitting and receiving coils. The on/off operation of the system is limited to a maximum 100 mm coil spacing. The switching circuitry has been implemented on a 28 ×43 mm ceramic substrate with reflow soldered integrated circuit leadless inverted devices (LID's?) and resistor and capacitor chips. It is expected that the reflow soldering can be duplicated easily by other investigators on either ceramic or glass-epoxy boards. The power transmitter and its battery pack are intended for placement in an animal jacket. The transmitter has a 2.5 W dc power input and will operate from a 1.2 A ·h, 12 V dc battery pack for the required recharging period. 相似文献
1000.
Hydrophilic and lipophilic oxygen radical antioxidant capacity (H&L-ORAC) of peanut flours, blanched peanut seed, and peanut skins were characterised across a range of roast intensities. H-ORAC ranged from 5910 to 7990, 3040 to 3700 and 152,290 to 209,710 μmoles Trolox/100 g for the flours, seed, and skins, respectively. H-ORAC increased linearly with darker seed colour after roasting at 166 °C from 0 to 77 min, whereas skin H-ORAC peaked after roasting for 7 min. Linear correlations with H-ORAC and total phenolic content were observed. Additionally, completely defatted peanut seed were solubilised (5% w/w) in water and H-ORAC measured. For these samples, H-ORAC decreased with roast intensity which correlated with soluble protein. L-ORAC ranged from 620 to 1120, 150 to 730 and 2150 to 6320 μmoles Trolox/100 g for peanut flours, seed, and skins, respectively. L-ORAC increased linearly with both darker seed colour and skin colour across the 77 min range. L-ORACs of roasted peanuts and ingredients are discussed in terms of tocopherol contents and Maillard reaction products. 相似文献