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991.
Jose S. Pulido Ikuko Sugaya Jordan Comstock Kiminobu Sugaya 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(6):889-893
Purpose Reelin is important in the guidance of neuronal stem cells in the central nervous system during normal development. We wished
to determine whether reelin is expressed in the retina and cornea after injury.
Methods Mice underwent laceration of their retina as well as corneal epithelial debridement. The mice were sacrificed at 3 days, and
eyes were fixed and stained for reelin expression and reelin messenger ribonucleic acid (mRNA).
Results In normal eyes, reelin was expressed only at very low levels in the ganglion cell layer of the retina and the endothelial
cell layer of the cornea. In injured eyes, there was marked expression in reelin immunoreactivity in the retina and cornea.
Reelin gene expression was seen in the retina and cornea.
Conclusions Reelin is expressed during normal retinogenesis. This study shows that reelin is also upregulated following injury to the
retina and cornea. The expression of reelin following injury suggests that reelin may play an important role in regulating
stem cell trafficking in neuronal and nonneuronal tissues following injury similar to its role in normal organogenesis.
For consideration of publication in Graefe’s Archive for Clinical and Experimental Ophthalmology. 相似文献
992.
Distribution of thymic tissue in the mediastinal adipose tissue. 总被引:5,自引:0,他引:5
I Fukai Y Funato T Mizuno T Hashimoto A Masaoka 《The Journal of thoracic and cardiovascular surgery》1991,101(6):1099-1102
The distribution of thymic tissue in the anterior mediastinal, retrocarinal, and preaortic fat was examined histologically in 27 autopsy subjects. Thymic tissue was found in the anterior mediastinal fat in 12 subjects (44.4%), in the retrocarinal fat in two (7.4%), and in the preaortic fat in none. The finding of ectopic thymic tissue in these areas has not been reported previously, would appear to be surgically inaccessible via a median sternotomy, and may be responsible in part for some of the failures of thymectomy in the treatment of myasthenia gravis. 相似文献
993.
H. S. Lee H. Y. Meltzer M.D. 《Journal of neural transmission (Vienna, Austria : 1996)》1991,86(1):71-76
Summary Buspirone, a putative serotonin (5-HT)1A partial agonist, did not produce hypothermia in 17 normal volunteers in a placebo controlled, single blind study. Thus, buspirone may be a weaker agonist at those 5-HT1A receptors which mediate hypothermia compared to ipsapirone or gepirone, two other 5-HT1A partial agonists which have been reported to produce hypothermia by a 5-HT1A-mediated mechanism. 相似文献
994.
995.
2-Cyclohexene-1-one (CHX) dose-dependently caused the elevation of blood glucose levels in both fed and fasted mice. Adrenalectomy considerably prevented the elevated blood glucose with CHX, and plasma adrenaline assays revealed about a three- to fifteen-fold rise after CHX treatment. These findings indicate that the CHX-induced hyperglycemia may be largely mediated by adrenaline released from the adrenal medulla. 相似文献
996.
L D Nord R C Willis T S Breen T L Avery R A Finch Y S Sanghvi G R Revankar R K Robins 《Biochemical pharmacology》1989,38(20):3543-3549
The basis for the antitumor activities of the exocyclic amino nucleosides 4-amino-(ARPP) and 4-methoxy-8-(D-ribofuranosylamino)pyrimido[5,4-d]pyrimidine (MRPP) was investigated. The primary target of these nucleosides appeared to be 5-phospho-alpha-D-ribofuranose-1-pyrophosphate (PRPP) synthetase. MRPP-5'-monophosphate was a competitive inhibitor (Ki = 40 microM) of the activation of this enzyme by the cofactor inorganic phosphate (K alpha = 2.2 mM). Consequently, ARPP and MRPP treatment of WI-L2 cultures rapidly inhibited both de novo pyrimidine and purine synthesis as well as the nucleotide salvage reactions dependent on PRPP, ARPP or MRPP treatment completely prevented [14C]bicarbonate incorporation into acid-soluble pyrimidine and purine nucleotides. The rate of salvage of [8-14C]hypoxanthine to form IMP was decreased by 85%. Treatment of cells with these agents caused a 50% reduction in the steady-state level of PRPP. When the capacity of the treated cells for sustained synthesis of PRPP was examined by adenine incorporation, the rate of adenine uptake was inhibited by greater than 50%. In vivo treatment of BDF1 mice with a single dose of ARPP (173 mg/kg) or MRPP (62 mg/kg) extended the mean life span of the mice, which had been inoculated intraperitoneally 1 day earlier with 1 x 10(6) L1210 murine leukemia cells, by 62 and 82% respectively. These studies indicate that MRPP and ARPP inhibit PRPP synthetase, and that PRPP synthetase may be a viable target in the development of certain antitumor agents. 相似文献
997.
Y Aso Y Ohtawara K Fukuta H Sudoko M Nakano T Ushiyama N Ohta K Suzuki A Tajima 《The Journal of urology》1987,137(4):629-632
We tested 2 prototypes of an operating fiberoptic nephroureteroscope, measuring 3.5 and 4.5 mm. in diameter, that have an adequate working channel for auxiliary instruments and irrigation. Difficulty in passing the fiberscope through the ureteral orifice was overcome by dilation with balloon and polytetrafluoroethylene (Teflon) dilators. Our initial trial for stone retrieval under fiberscopic control was performed on 21 patients with upper ureteral and renal calculi. A stone was removed successfully in 15 of the 21 patients (71 per cent). After electrohydraulic lithotripsy calculi were extracted successfully in 9 of 11 patients (82 per cent). Three patients suffered ureteral perforation. The fiberscope was especially helpful when an upper ureteral stone moved back to the kidney during stone manipulation. 相似文献
998.
Optically pure (+)- and (-)-trans-stilbene oxide (TSO) enantiomers were administered to immature male Sprague-Dawley rats. (+)-TSO was the more potent inducer of liver microsomal cytochrome P-450-dependent monooxygenases. The greater potency of (+)-TSO may be explained on the basis of stereoselective metabolism since a far greater concentration of TSO was found in liver microsomes of (+)-TSO-treated rats. Furthermore, of the enzymes known to metabolize TSO, cytosolic epoxide hydrolase turned over the (-)-TSO enantiomer at a faster rate, consistent with the greater persistence of the (+)-enantiomer. Although this report is of chiral effects in potency of enzyme induction, stereoselective metabolism (i.e. disposition) rather than inherent structural characteristics (recognition) may be responsible for these effects. 相似文献
999.
A case of generalized eruptive histiocytoma (GEH) was evaluated and examined histopathologically and ultrastructurally. A 24-year-old male had an episode of high fever and drug-induced eruption prior to the appearance of multiple skin lesions. Uniform, red to dark-red papular lesions appeared on his cheeks and then became generalized. The lesions were composed of a massive dermal infiltrate of histiocytes, which had oval nuclei and amphophilic cytoplasm. The cytoplasm contained unique annular structures, myeloid bodies and vacuoles. The specificity of these structures is as yet unknown. Reactive stimulation rather than neoplastic proliferation may be a causative factor in GEH. 相似文献
1000.
The promoting effect of the Chinese medicinal herb, Wikstroemia chamaedaphne and Tung oil extracts (WC and HHPA) on carcinoma of uterine cervix induced by HSV-2 or MCA in mice was studied. The results showed that WC and HHPA extracts were not carcinogenic themselves. After carcinogen HSV-2 and MCA treatment, WC and HHPA were added separately. The inducing rates by HSV-2 increased from 7.4% to 21.1% and 26.3%, those by MCA increased from 56.5% to 82.8% and 84.4%. There was a significant difference between the combined groups and groups with HSV-2 or MCA only. The experimental results suggest that these two kinds of extracts play a promoting effect on carcinogenesis. The relation between the carcinogenesis of uterine cervix or nasopharynx and WC or HHPA extracts is discussed. 相似文献