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11.
F Diaz-Mitoma M Ruben S Sacks P MacPherson G Caissie 《Canadian Metallurgical Quarterly》1996,34(3):657-663
Culture of infectious virus, PCR amplification of viral DNA, and the appearance of genital skin lesions were used as markers to study the course of a recurrence of genital herpes in 40 patients treated with famciclovir or placebo. The highest frequency of patients with skin lesions occurred within the first 36 h following the onset of a recurrence, which also corresponded to the peak in the production of virus. While the timing of the peak in skin lesions was independent of the type of treatment, the frequency of lesions and the release of virus at the lesion site were both reduced by famciclovir treatment. Furthermore, patients receiving this antiviral agent showed a more rapid recovery time and a shorter period during which viral DNA could be detected at the lesion. PCR and then Southern blot hybridization greatly enhanced our ability to detect herpes simplex virus at the lesion site. This procedure proved to be of greater diagnostic value in assessing genital herpes than the standard culture method currently used. In addition, PCR was more sensitive in evaluating treatment effectiveness. 相似文献
12.
Experimental colitis 总被引:1,自引:0,他引:1
Ulcerative colitis and Crohn's disease are complex, problematic diseases of unknown etiology in man, and appropriate experimental models would be useful in elucidating their pathogenesis and treatment. Although there have been numerous attempts to produce inflammatory ulcerative colonic disease in laboratory animals resembling those human disease forms, none has been entirely successful. Investigators have conducted experiments involving almost every etiological factor suggested for initiation of these diseases. The methods reviewed in this paper include production of experimental colitis by vascular impairment, and immunological methods such as bacterial infection, allergic reactions, direct and indirect hypersensitivity reactions, as well as autoimmune mechanisms. The results of carrageenan-induced colitis, irradiation, dietary, and drug-induced techniques are also discussed and the frequency and nature of spontaneous colonic lesions in animals is summarized. 相似文献
13.
Silva-López M MacPherson WN Li C Moore AJ Barton JS Jones JD Zhao D Zhang L Bennion I 《Applied optics》2005,44(32):6890-6897
We demonstrate the sensitivity of Bragg gratings in a multicore fiber to transverse load. The Bragg peaks are split because of stress-induced birefringence, the magnitude of which depends upon the load and grating position relative to the load axis. Experiments show that a set of gratings in a four-core fiber can measure a load axis angle to +/- 5 degrees and a load magnitude to +/- 15 N m(-1) up to 2500 N m(-1). We consider alternative designs of multicore fiber for optimal load sensing and compare experimental and modeled data. 相似文献
14.
The crucial energy problem of this century is the balance between supply and demand for liquid fuels. Our conventional petroleum source is limited and much of it comes from countries that we consider unstable. Our near-term national energy effort should be devoted almost exclusively to reducing our dependence on petroleum, using every means at our disposal. Our present fleet of automobiles should be replaced as soon as possible with cars using less than half as much gasoline and with electrically propelled vehicles. We must move faster on the production of liquid fuels from coal and oil shale. A way must be found to cut through the politics and financial problems of converting our oilfired electricity generating plants to the use of coal or uranium. Houses and stores that are now heated with oil should be insulated to use less fuel and should be converted to heating with electricity, provided that the electricity is produced from coal or uranium. Our transmission lines should be strengthened so that electricity generated from coal or uranium can be wheeled to oil-burning areas of the country. Even with these measures and more, it will take all of the remainder of this century to reach even a moderately comfortable position with respect to liquid fuels. While this is happening we can expect to be sharing our ample supplies of coal with other NATO countries, and what we thought was several centuries' worth of coal will turn out to be more like one century's worth. 相似文献
15.
CVI is a common disease with significant morbidity that results from venous hypertension of the extremities. Increased perfusion pressure probably traps excessive numbers of white blood cells in the capillaries. Activated leukocytes subsequently damage capillary endothelium, increase capillary permeability, and cause ischemia of the overlying skin as a result of leakage of fibrinogen and formation of a fibrin cuff. Diagnosis of CVI is not difficult because its clinical manifestations are usually evident. Vascular compression therapy remains the foundation of medical management for CVI. Refractory cases may require a combined medical and operative approach. 相似文献
16.
In the rat, mesenteric lymphadenectomy allows collection of dendritic cells (DC) derived from the small intestine after cannulation of the thoracic duct. We prepared rats this way and administered antigens by oral feeding or intraintestinal injection. DC enriched from the thoracic duct lymph collected over the first 24 h from these animals are able to stimulate sensitized T cells in vitro and to prime popliteal lymph node CD4+ T cells after footpad injection, while B and T cells from the same thoracic duct lymph are inert in priming. 500 or less DC pulsed in vitro with antigen can prime T cells in vivo, whereas 100 times more B cells or macrophages pulsed in vitro are quite inert. 1 mg of ovalbumin administered orally is sufficient to load DC for in vivo priming of T cells. Antigen could not be detected directly in DC but was present in macrophages in the lamina propria. Direct presentation of antigen by DC to T cells was demonstrated by injecting F1 recipients with parental DC and showing restriction of T cell sensitization to the major histocompatibility complex of the injected DC. Antigen-bearing DC do not induce a detectable primary antibody response but a small secondary antibody response can be detected after a boosting injection. These results show that acquisition of antigens by DC in the intestine is very similar to what occurs in vitro or in other tissues, suggesting that there may be no special difference in antigen handling at mucosal surfaces. One implication of these results is that hypotheses designed to explain oral tolerance must take into account the presence of immunostimulatory, antigen-bearing DC in animals that have received oral antigens. 相似文献
17.
ABSTRACT We present a model of the optimum market size of a producer service firm that is based on that contact requirements of its service as well as the firm's distance to its prospective clients. The effects on market size of differing contact requirements are discussed from a comparative statics perspective. Optimum market sizes are shown to vary with different values of service duration and demand frequency. These differences may exist between producer service industries, and they may also arise from changes over time in the market requirements of a particular industry. The paper concludes with suggestions for improving the muscle. An impartial agenda for advancing the modeling interests of service-sector researchers also presented. 相似文献
18.
MacPherson WN Reeves M Towers DP Moore AJ Jones JD Dale M Edwards C 《Applied optics》2007,46(16):3126-3132
Experimental modal analysis of multifrequency vibration requires a measurement system with appropriate temporal and spatial resolution to recover the mode shapes. To fully understand the vibration it is necessary to be able to measure not only the vibration amplitude but also the vibration phase. We describe a multipoint laser vibrometer that is capable of high spatial and temporal resolution with simultaneous measurement of 256 points along a line at up to 80 kHz. The multipoint vibrometer is demonstrated by recovering modal vibration data from a simple test object subject to transient excitation. A practical application is presented in which the vibrometer is used to measure vibration on a squealing rotating disk brake. 相似文献
19.
The phospholipid composition was determined for the amebocyte of the primitive arthropod Limulus polyphemus. The total fatty acid composition of the cells' lipids was analyzed by gas chromatography/mass spectrometry (GC/MS) of fatty
acid methyl esters (FAME). The FAME analysis revealed high levels of 20-carbon polyunsaturated fatty acids (PUFA), especially
arachidonic (20∶4n-6) and eicosapentaenoic (20∶5n-3) acids. Almost 20% of the total lipid profile was comprised of dimethyl
acetals of 16- to 20-carbon chain lengths, indicative of plasmalogens in the phospholipid pool. Phospholipids, analyzed by
high-pressure liquid chromatography, included phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine
(PS), phosphatidylinositol (PI), sphingomyelin (SPH), and cardiolipin (CL). PE and PC levels predominated at 42.2 and 36.3%,
respectively. Smaller amounts of PS (9.0%) and PI (6.2%) were present, as well as low levels of SPH (4.6%), CL (1.6%), and
trace amounts of lysophosphatidylcholine. The major phospholipid species, PE, PC, PS and PI, were collected and their molecular
species were examined by electrospray-ionization mass spectrometry. The molecular species within the phospholipid classes
reflected the high levels of PUFA seen in the total lipid profile. PI was mainly composed of 18∶0a/20∶4. Over half of the PS consisted of 18∶0a/18∶1 and 18∶0a/20∶4. The major PE species were 20∶1p/20∶5, 20∶1p/20∶4, 18∶0p/20∶5, and 18∶0p/20∶4. PC had the largest distribution of molecular species, and its most abundant species were 16∶0e/20∶5, 16∶0e/20∶4, and 16∶0p/20∶4. The presence of 16∶0e/20∶4 is the first documentation of a specific precursor to platelet-activating factor in an invertebrate hemocyte. Note:
at the sn-1 position: [a=1=O-acyl, e=1-O-alkylether, and p=1-O-alk-1′-enyl (plasmalogen)]. 相似文献
20.
Fender A Rigg EJ Maier RR MacPherson WN Barton JS Moore AJ Jones JD Zhao D Zhang L Bennion I McCulloch S Jones BJ 《Applied optics》2006,45(36):9041-9048
We describe the use of arrayed waveguide gratings (AWGs) in the interrogation of fiber Bragg gratings (FBGs) for dynamic strain measurement. The ratiometric AWG output was calibrated in a static deflection experiment over a +/-200 microepsilon range. Dynamic strain measurement was demonstrated with a FBG in a conventional single-mode fiber mounted on the surface of a vibrating cantilever and on a piezoelectric actuator, giving a resolution of 0.5 microepsilon at 2.4 kHz. We present results of this technique extended to measure the dynamic differential strain between two FBG pairs within a multicore fiber. An arbitrary cantilever oscillation of the multicore fiber was determined from curvature measurements in two orthogonal axes at 1125 Hz with a resolution of 0.05 m(-1). 相似文献