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1.
2.
PL Smith 《Canadian Metallurgical Quarterly》1996,11(3):196-199
The acquired immune deficiency syndrome (AIDS) is a lethal multisystem disease. Its ocular manifestations have received relatively little attention in the literature. Between 73% and 100% of AIDS patients develop ocular lesions. The commonest lesions seen are retinal--either infectious or noninfectious retinopathy. Involvement of the conjunctiva with Kaposi's sarcoma, infected tears and infected cornea as well as the vitreous are less common. Infections with cytomegalovirus and varicella zoster virus are common causes of visual loss and can be treated with antiviral agents such as ganciclovir and foscarnet. This greatly increases the quality of life in these patients by preventing visual loss. 相似文献
3.
PL Pirie BL Rooney TF Pechacek HA Lando LA Schmid 《Canadian Metallurgical Quarterly》1997,22(1):131-137
Exposure to foreign particles sometimes causes inflammatory reactions through production of cytokines and chemoattractants by phagocytic cells. In this study, we focused on macrophage migration inhibitory factor (MIF) to evaluate its pathophysiological role in the phagocytic process. Immunohistochemical analysis of human pseudosynovial tissues retrieved at revision of total hip arthroplasty showed that infiltrating mononuclear and multinuclear cells were positively stained by both an anti-CD68 antibody and anti-human MIF antibody. For in vitro study, MIF was released from murine macrophage-like cells (RAW 264.7) in response to phagocytosis of fluorescent-latex beads in a particle dose-dependent manner. Northern blot analysis showed marked elevation of the MIF mRNA level in the phagocytic macrophage-like cells. Moreover, pretreatment of RAW 264.7 cells with rat recombinant MIF increased the extent of phagocytosis by 1.6-fold compared with the control. Taken together, these results suggest that MIF plays an important role by activating macrophages in autocrine and paracrine fashion to phagocytose foreign particles. 相似文献
4.
Prostaglandin (PG) production by human amnion has been postulated to have a role in the onset of labor. Previous work by ourselves and others has demonstrated that oxytocin, phorbol esters and epidermal growth factor (EGF) increase PGE2 production in human amnion cells by activation of the Phospholipase C/Protein Kinase C (PKC) cascade system. The present study was undertaken to determine the effect of prior activation of the Adenylate Cyclase cascade system upon subsequent stimulation of PGE2 production by oxytocin, phorbol 12-myristate-13-acetate (PMA) or EGF in amnion cells and membrane discs. Isoproterenol, forskolin and dibutyryl cyclic adenosine monophosphate (dbcAMP) were utilized to activate the Adenylate Cyclase system at the receptor, enzyme and second messenger level. In control amnion cells, oxytocin, PMA and EGF each provoked dose dependent increases in PGE2 production. In cells preincubated with dbcAMP, forskolin or isoproterenol, agonist stimulated PGE2 production was markedly (50-90%) inhibited (p < 0.01). Inhibition was dose dependent upon preincubator concentrations. Maximal inhibition by adenylate cyclase activators occurred with 2-4 h of preincubation. In membrane discs, forskolin preincubation also inhibited oxytocin, PMA and EGF stimulation of PGE2 production. Activation of the Adenylate Cyclase system in human amnion cells or membrane discs inhibits the subsequent action of potent stimulators of PGE2 production in human amnion. 相似文献
5.
In this study we have employed the whole cell patch clamp technique to investigate the effects of an anti-cancer drug cisplatin on basic electrophysiological properties of cultured dorsal root ganglion neurones from neonatal rats. The results show that within the clinical concentration range, cisplatin (0.1 to 10 microM) caused a decrease in input conductance, and complex changes in resting membrane potential in these cultured sensory neurones. The dominant effects of cisplatin on input conductance may be due to inhibition of leak conductances. Transplatin (5 microM) was significantly less effective than cisplatin at reducing input conductance which suggests a degree of stereoselectivity. Cisplatin (1 to 5 microM) transiently increased excitability of the cultured neurones as reflected by a reduction in the threshold for activation of action potentials by 8 mV. The rise time, peak amplitude and duration of action potentials were not changed by acute application of 5 microM cisplatin. Long term treatment of neurones with cisplatin (5 microM), for up to 1 week reduced the viability of the cultures, and attenuated neurone excitability, although input conductance of the cells was significantly increased to 322 +/- 49 M omega (n = 9) compared with controls of 210 +/- 20 M omega (n = 30; P < 0.05). Acute and chronic treatment of cultured neurones with cisplatin therefore produced contrasting actions. 相似文献
6.
GL Anderson KN Caldwell LR Beuchat PL Williams 《Canadian Metallurgical Quarterly》2003,66(9):1543-1549
Free-living nematodes may harbor, protect, and disperse bacteria, including those ingested and passed in viable form in feces. These nematodes are potential vectors for human pathogens and may play a role in foodborne diseases associated with fruits and vegetables eaten raw. In this study, we evaluated the associations between a free-living soil nematode, Caenorhabditis elegans, and Escherichia coli, an avirulent strain of Salmonella Typhimurium, Listeria welshimeri, and Bacillus cereus. On an agar medium, young adult worms quickly moved toward colonies of all four bacteria; over 90% of 3-day-old adult worms entered colonies within 16 min after inoculation. After 48 h, worms moved in and out of colonies of L. welshimeri and B. cereus but remained associated with E. coli and Salmonella Typhimurium colonies for at least 96 h. Young adult worms fed on cells of the four bacteria suspended in K medium. Worms survived and reproduced with the use of nutrients derived from all test bacteria, as determined for eggs laid by second-generation worms after culturing for 96 h. Development was slightly slower for worms fed gram-positive bacteria than for worms fed gram-negative bacteria. Worms that fed for 24 h on bacterial lawns formed on tryptic soy agar dispersed bacteria over a 3-h period when they were transferred to a bacteria-free agar surface. The results of this study suggest that C. elegans and perhaps other free-living nematodes are potential vectors for both gram-positive and gram-negative bacteria, including foodborne pathogens in soil. 相似文献
7.
A Van Aarem M Wagenaar AJ Pinckers PL Huygen EM Bleeker-Wagemakers BJ Kimberling CW Cremers 《Canadian Metallurgical Quarterly》1995,16(4):151-158
Thirty-seven patients, comprising 24 familial cases and 13 isolated patients with Usher syndrome type II (USH2), underwent ophthalmologic examination. Based on the degree of hearing loss, normal vestibular function, and gene-linkage analysis, familial cases were assumed to have USH2A. An analysis of genetic heterogeneity failed to reveal the presence of a second locus in the Dutch population. Although the patients appear to belong to a genetically homogeneous group, remarkable ophthalmologic variability was found. Corrected visual acuity decreased with age and remarkable differences in visual acuity were found within one family. Fundoscopic findings were classified as type A if attenuated vessels and bone corpuscles in all quadrants were found or as type B if findings other than these were found. The prevalence of type A significantly increased with age. 相似文献
8.
From the rhizomes of Polygonatum alte-lobatum, two new homologous series of 1,4-benzoquinones, polygonaquinones A and B, a novel homoisoflavanone, a new gentrogenin glycoside and 13 known compounds were isolated and characterized. The structures of the new compounds were determined as two homologous series of three 2,5-dihydroxy-3-methyl-6-alkyl-1,4-benzoquinones and three 2-hydroxy-3-methyl-6-alkyl-1,4-benzoquinones, with chain lengths C21 to C23, and 4',5,7-trihydroxy-6,8-dimethylhomoisoflavanone and gentrogenin 3-O-beta-D-glucopyranosyl(1-->2)-[beta-D-xylopyranosyl(1-->3)] -beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside. 相似文献
9.
Uterine angiomyolipomas are rare lesions composed of mature adipose tissue, smooth muscle, fibrous connective tissue, and blood vessels in varying proportions. We reported the first case of angiomyolipoma associated with a normal pregnancy. Initially, the tumor developed intramurally and could have been confused with a partial molar gestation. After delivery, tumor development was extensive and subserosal, making differential diagnosis from a sarcoma difficult. The question of histological diagnosis, as well as that of immunocytochemical analysis which seems to be helpful in such cases, is discussed here. 相似文献
10.
TJ Schnitzer JR Donahue EP Toomey RM Holtby GR Scuderi PL Adams MP Poland 《Canadian Metallurgical Quarterly》1998,20(1):110-124
The known effects of commonly used nonsteroidal anti-inflammatory drugs (NSAIDs) on hemostatic parameters have led to concern over their use in the perioperative period. Nabumetone, unlike other NSAIDs, has little effect on collagen-induced platelet aggregation. To evaluate the effect of nabumetone 2000 mg daily on other hemostatic parameters (e.g., bleeding time, prothrombin time, and partial thromboplastin time) in the clinical setting, this double-masked study was conducted in patients with osteoarthritis undergoing arthroscopic knee surgery. After a 1-week placebo washout period, 58 patients were randomized to receive nabumetone and 53 were randomized to receive placebo. They were assessed before surgery (after 1 to 2 weeks of treatment) and again after surgery (after an additional 3 weeks of treatment). The study was designed to have 90% power to show equivalence in bleeding time to within 1.5 minutes, a difference assumed to be of no clinical importance. No meaningful differences were observed between the groups in any of the measured hemostatic parameters. Before surgery, the bleeding time increased by only 0.3 minutes with nabumetone and decreased by 0.2 minutes with placebo. The mean (+/- SD) difference between the groups in change from baseline was 0.5 +/- 0.3 minutes. After surgery, the changes were 0.1 minutes and 0.0 minutes, respectively, and the difference between groups was 0.2 +/- 0.3 minutes. These differences were neither statistically nor clinically significant, and maximum individual increases were similar in each group. Furthermore, there were no reports of abnormal bleeding in the operative knees. The results of this study show that nabumetone had little or no effect on hemostasis and suggest that this drug can be used safely in the perioperative period. 相似文献