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71.
J. J. Bernstein L. A. Willingham W. J. Goldberg 《Journal of neuroscience research》1993,34(4):394-400
Nerve growth factor (NGF) immunoreactivity in the nucleus gracilis of the medulla was quantitated for 90 days after aspiration of the C3 spinal hindlimb dorsal columns of 36 adult rats. Half the lesioned animals were a lesion-only group. The remaining lesioned animals received an immediate graft of two 1.0-mm pieces of 14 day gestation fetal rat cervical spinal cord (prelabeled with Phaseolus vulgaris leucoagglutinin) into the aspiration pocket (graft group). There were 3 normal controls. Groups of animals were analyzed at 7, 14, 21, 30, 60, and 90 days. At 90 days, NGF immunoreactivity was significantly elevated in the nucleus gracilis of lesion-only animals. This increase in NGF immunoreactivity was augmented in glial end-feet surrounding neurons and was also observed in the cytoplasm of astrocytes and some neurons. Previous experiments have shown that the cluster neurons of the nucleus gracilis undergo atrophy at this time with a concomitant decrease in hindlimb placement. NGF immunoreactivity (90 days) in grafted animals, however, was significantly less than in lesion-only animals (P < 0.05) but remained significantly elevated above control animals (P < 0.05). Unlike in lesion-only animals, there were no NGF positive neurons in the nucleus gracilis of grafted animals. Previous experiments have shown that astrocytes from fetal spinal cord grafts migrate to the nucleus gracilis, maintain cluster neuron cell size, and improve hindlimb placement at 90 days. The present data indicate that modulation of detrimental increases in NGF appeared to be a mechanism by which migrated fetal astrocytes can be used as a system for cell therapy. © 1993 Wiley-Liss, Inc. 相似文献
72.
Routine obstetric ultrasound (US) examinations in a 33-year-old woman revealed a normal fetal gallbladder at 24 menstrual weeks but multiple structures in the gallbladder with findings typical of gallstones at 37 menstrual weeks. No other abnormalities were present. Three days after a term delivery, an abdominal US examination again demonstrated multiple gallstones. When the infant was 6 weeks old, a follow-up abdominal US study showed no evidence of gallstones. This case, as well as one previously reported, demonstrates that findings typical of gallstones may be seen in the fetus, and that these structures may spontaneously resolve. 相似文献
73.
ABSTRACT – Deposits of immunoglobnlins were demonstrated at the basement membrane zone in oral lesions in 10 out of 11 patients with lupus erythematosus (LE), and in normal oral mucosa in one out of six patients with LE by means of an imniunofluorescence staining technique. The reported findings are in accordance with the findings in skin biopsies from cutaneous LE lesions. In cases of LE, difficult to diagnose clinically and histopathologically, the imniunofluorescence staining technique may be of value as a supplementary diagnostic tool. 相似文献
74.
OLE DONATSKY NILS WORSAAE MORTEN SCHIÖDT TORSTEN JOHNSEN 《European journal of oral sciences》1983,91(5):376-380
Abstract – A Double-blind clinical trial with cross-over was conducted for a period of 12 months in 25 patients with recurrent aphthous stomatitis (RAS). The effect of the amyloglucosidase and glucoseoxidase containing Zendium toothpaste on the discomfort, number of exacerbations, duration of exacerbation, number of ulcers and number of days with pain caused by RAS was studied. The use of Zendium significantly reduced the sensation of discomfort from RAS as compared to the use of placebo toothpaste (0.025>p>0.01). However, the patients were unable to discriminate significantly between Zendium and placebo when asked to choose one of the toothpastes (0.10>p>0.05) and no significant differences were demonstrated as far as the above mentioned parameters of disease serverity were concerned. Therefore, it is concluded that the reducing effect of Zendium containing amyloglucosidase and glucoseoxidase on RAS is weak as compared to a similar toothpaste without these enzymes. 相似文献
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Apoptosis regulators Bim and Fas function concurrently to control autoimmunity and CD8+ T cell contraction 总被引:3,自引:0,他引:3
Throughout most of adult life, lymphocyte number remains constant because of a balance of proliferation and apoptosis. Mutation of Bim, a proapoptotic protein in the intrinsic death pathway, or Fas, a tumor necrosis factor receptor (TNFR) superfamily member of the extrinsic pathway, results in late-onset autoimmunity and increased antigen-specific CD8(+) T cell responses during viral infection. However, virus-specific immune responses eventually return to amounts comparable to those for nonmutant mice. Here, we show that loss of both Bim and Fas function resulted in a synergistic disruption of lymphoid homeostasis, rapid-onset autoimmunity, and organ-specific blocks on contraction of antiviral immune responses. When lymphocytic choriomeningitis virus (LCMV)-specific immune responses were quantitated, double-mutant mice had 100-fold more antigen-specific memory CD8(+) T cells in their lymph nodes than wild-type mice. Our results demonstrate that multiple death pathways function concurrently to prevent autoimmunity and downsize T cell responses. 相似文献
80.
HE Connor W Feniuk DT Beattie PC North AW Oxford DA Saynor PPA Humphrey 《Cephalalgia : an international journal of headache》1997,17(3):145-152
The biological profile of naratriptan (N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethane-sulphona-mide), a novel 5HT1B/1D receptor agonist, was investigated in a variety of experimental models of relevance to migraine. Naratriptan has high affinity for human recombinant 5HT1B and 5HT1D receptors (pKi = 8.70.03 and 8.30.1, respectively) and causes contractions of dog isolated basilar and middle cerebral artery (EC50 values of 0.11 and 0.07 M, respectively). Naratriptan causes small contractions of human isolated coronary arteries (EC50 value of 0.17 M; maximum contraction equivalent to 33% of 5HT maximum). In anaesthetized dogs, naratriptan causes selective vasoconstriction of the carotid arterial bed (CD50 dose = 193 g kg−1 ) and, in anaesthetized rats, naratriptan selectively inhibits neurogenic plasma protein extravasation in the dura (ID50 = 4.1 g kg−1 ). In a variety of antinociceptive tests, naratriptan has no effect even at high doses. In conscious rats and dogs, naratriptan has high oral bioavailability (71% and 95%, respectively). The data show that naratriptan is a selective agonist at 5HT1B/1D receptors, with a pharmacological profile very similar to that of sumatriptan, albeit 2-3 fold more potent. These observations, coupled with high oral bioavailability in animals, suggest that naratriptan has the profile of an orally effective anti-migraine drug. 相似文献