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991.
Reactivation of herpes simplex virus type 1 (HSV-1) in the trigeminal ganglion (TG) was induced by UV irradiation of the corneas of latently infected mice. Immunocytochemistry was used to monitor the dynamics of cytokine (interleukin-2 [IL-2], IL-4, IL-6, IL-10, gamma interferon [IFN-gamma], and tumor necrosis factor alpha [TNF-alpha]) and viral antigen production in the TG and the adjacent central nervous system on days 1 to 4, 6, 7, and 10 after irradiation. UV irradiation induced increased expression of IL-6 and TNF-alpha from satellite cells in uninfected TG. In latently infected TG, prior to reactivation, all satellite cells were TNF-alpha+ and most were also IL-6(+). Reactivation, evidenced by HSV-1 antigens and/or infiltrating immune cells, occurred in 28 of 45 (62%) TG samples. Viral antigens were present in the TG in neurons, often disintegrating on days 2 to 6 after irradiation. Infected neurons were usually surrounded by satellite cells and the foci of immune cells producing TNF-alpha and/or IL-6. IL-4(+) cells were detected as early as day 3 and were more numerous by day 10 (a very few IL-2(+) and/or IFN-gamma+ cells were seen at this time). No IL-10 was detected at any time. Our observations indicate that UV irradiation of the cornea may modulate cytokine production by satellite cells. We confirm that neurons are the site of reactivation and that they probably do not survive this event. The predominance of TNF-alpha and IL-6 following reactivation parallels primary infection in the TG and suggests a role in viral clearance. The presence of Th2-type cytokines (IL-4 and IL-6) indicates a role for antibody. Thus, several clearance mechanisms may be at work. 相似文献
992.
D Wang TJ Girard TP Kasten RM LaChance MA Miller-Wideman RC Durley 《Canadian Metallurgical Quarterly》1998,61(11):1352-1355
Five compounds, which inhibited the amidolytic activity of soluble tissue factor/activated factor VII complex (sTF/VIIa), were isolated from two traditional Chinese medicinal plants commonly used in the treatment of cardiovascular and cerebrovascular diseases. The active compounds were found to be linolenic, linoleic, and oleic acids from roots of Salvia miltiorrhiza; and two anacardic acids, 6-(8'Z-pentadecenyl)- and 6-(10'Z-heptadecenyl)-salicylic acids, from leaves of Ginkgo biloba. The IC50 values were in the range 30-80 micromol/L. Palmitic acid, isolated from roots of Salvia miltiorrhiza, and 2-[(3',7',11',15'-tetramethyl)-2'E,6'E,10'E, 14'E-hexadecatetraenyl]-1,4-hydroquinone, isolated from the marine sponge Adocia viola, did not inhibit sTF/VIIa. Further expansion of the structure-activity relationship to include anacardic acids, 6-(8'Z,11'Z-heptadecadienyl)- and 6-(8'Z, 11'Z, 14'Z-heptadecatrienyl)-salicylic acids from leaves of Anacardium spondias, and other fatty acids demonstrated that at least one cis double bond was essential for inhibitory activity, and that fatty acids containing two or three cis double bonds were optimal. Evidence from preincubation studies implied that these fatty acids may exert their effect by binding to VIIa and consequently preventing binding of sTF to VIIa. 相似文献
993.
SM Pyo SI Kim TJ Shin HK Park M Ree KH Park JS Kang 《Canadian Metallurgical Quarterly》1998,31(15):4777-4781
5,5'-Bis(4-aminophenyl)-2,2'-bifuryl (PFDA) with a well-defined conjugation length was synthesized, and its soluble poly(amic acid) was prepared by polycondensation with pyromellitic dianhydride (PMDA). The PMDA-PFDA polyimide films were obtained from the poly(amic acid) solution through a conventional spin-casting, baking, and thermal imidization process. The PFDA monomer exhibits intense blue photoluminescence with a maximum at 442 nm in a high quantum yield of 0.92, whereas its polyimide film also emits intense blue photoluminescence with double peak maxima at 419 and 436 nm. The polyimide is insoluble in common organic solvents and thermally stable up to 370 degreesC. Overall, the PMDA-PFDA polyimide can be considered to be a potential candidate material for fabricating optoelectronic devices that emit blue light. 相似文献
994.
KS Lee BI Kim B Khoshnood HL Hsieh TJ Chen M Herschel R Mittendorf 《Canadian Metallurgical Quarterly》1995,141(12):1188-1193
Neonatal intensive care has led to a progressive improvement in the survival of very low birth weight (VLBW, < 1,500 g) infants. However, it has not been established whether there has been a simultaneous increase or decrease in the prevalence of handicapping conditions in this group of children. To explore this question, a meta-analysis was performed using outcome data of 32 developmental studies of VLBW infants born in industrialized countries between 1947 and 1987. The authors' results show that the proportion of VLBW infants who survived and had an intact outcome progressively increased between 1947 and 1987--from 147 per 1,000 live births in the period 1947-1965 to 498 per 1,000 in the period 1980-1987 (p < 0.01). The prevalence of major handicapping conditions for the subset of VLBW infants who weighed < 1,000 g at birth increased, resulting from the increasing survival rates. However, the prevalence of major handicapping conditions among all children with VLBW decreased from 147 per 1,000 live births in 1947-1965 to 45 per 1,000 in 1980-1987 (p = 0.02). The authors' meta-analysis suggests that improved survival of VLBW infants has not been accompanied by an increase, but more likely a decrease, in the prevalence of handicapping conditions in this birth weight group. 相似文献
995.
996.
997.
Vision is not required in order for fish to school. Five individual saithe, Pollachius virens, were able to join schools of 25 normal saithe swimming in an annular tank, while blinded with opaque eye covers. Test fish maintained position within the school indefinitely and responded to short-term movements of individuals within the school, although quantitative differences in reaction time and schooling behavior were noted. Five fish with lateral lines cut at the opercula were unable to school when wearing opaque eye covers. Although it is unlikely that blind saithe could school in the wild, the constraints of the apparatus permitted a demonstration of a role of the lateral line organ in schooling. 相似文献
998.
RH Higgs TJ Humphries DO Castell JE McGuigan 《Canadian Metallurgical Quarterly》1976,231(4):1250-1253
To define the role of gastrin, if any, in the response of the lower esophageal sphincter (LES) to bethanechol, serum gastrin determinations and LES pressure measurements were made in controls, patients with vagotomy and antrectomy (V&A), and patients with vagotomy and pyloroplasty (V&P). Despite significant differences in mean basal serum gastrin levels no differences were found in mean resting LES pressures among these groups. In controls significant increases in LES pressure occurred after subcutaneous bethanechol, but serum gastrin levels did not change from basal values. Subcutaneous injections of bethanechol produced significantly greater increases in LES pressures in V&P patients than in V&A patients. Serum gastrin levels did not change in either group; however, background serum gastrin concentrations were significantly greater for V&P patients than V&A patients throughout the study. Intravenous infusion of human gastrin I heptadecapeptide in controls significantly increased sphincter responses to bethanechol. Thus, these studies provide evidence to suggest that the LES response to bethanechol is affected by background serum gastrin levels. 相似文献
999.
1000.