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71.
Kim DG  Lee S  Lim JS 《Neuroreport》1999,10(12):2551-2556
To determine the effects of stress early in life on adult behavior and hippocampal corticosteroid receptors, rats were exposed to footshocks (0.8 mA, 60 times/day, randomly apart) on postnatal days 14, 17 and 20. When they reached 6 months of age, neurobehavioral alterations were measured. The footshock-experienced rats learned more rapidly in the autoshaped learning test than similarly handled controls. They also stabilized more quickly after exposure to a novel environment than the handled controls, but only at the same rate as animals which had not been handled except for weighing. The density of [3H]dexamethasone binding sites increased and that of [3H]corticosterone binding sites decreased in the hippocampi of these rats. These results indicate that early life stress results in altered behavior and hippocampal corticosteroid receptors at adulthood, and suggest that the mineralocorticoid and the glucocorticoid receptors are differentially regulated by early life stress.  相似文献   
72.
An inhibitor of cyclooxygenase (COX)-1 activity of prostaglandin H2 synthase was isolated from aerial parts of Celastrus orbiculatus Thunb. (Celastraceae), an oriental folk medicine for rheumatoid arthritis by activity-guided column chromatographic methods. The COX inhibitor was identified as (-)-epiafzelechin, a member of flavan-3-ols by the structural analysis with HR-EI-mass, 1H-NMR and 13C-NMR spectral data. The compound exhibited a dose-dependent inhibition on the COX activity with an IC50 value of 15 microM. (-)-Epiafzelechin exhibited about 3-fold weaker inhibitory potency on the enzyme activity than indomethacin as a positive control. (-)-Epiafzelechin exhibited significant anti-inflammatory activity on carrageenin-induced mouse paw edema when the compound (100 mg/kg) was orally administrated at 1 h before carrageenin treatment.  相似文献   
73.
Kwon BM  Jung HJ  Lim JH  Kim YS  Kim MK  Kim YK  Bok SH  Bae KH  Lee IR 《Planta medica》1999,65(1):74-76
Fifteen lignans were isolated from the fruits of SCHIZANDRA CHINENSIS, the leaves of MACHILUS THUNBERGII, and the flower buds of MAGNOLIA DENUDATA. They were identified as gomisins, schizandrin, wuweizisu, schizantherin, licarins, and machilin, which inhibited rat liver ACAT with IC (50) values of 25-200 microM. Comisin N is the most potent inhibitor with IC (50) value of 25 microM in these lignans.  相似文献   
74.
Activity-guided fractionation of the roots of Anthriscus sylvestris resulted in the isolation and characterization of five cytotoxic compounds, deoxypodophyllotoxin (1), falcarindiol (2), and angeloyl podophyllotoxin (5) from the hexane soluble fraction and morelensin (3), bursehernin (4) from the chloroform soluble fraction. It is the first report of the occurrence of compound 5 in nature.  相似文献   
75.
For the past year, indocyanine green angiography has been applied to evaluation of choroidal neovascularization, pigment epithelial detachment, retinal vascular disorders, and choroidal diseases and tumors. These applications have expanded the potential use of this technique. The relative safety of indocyanine green angiography has contributed to its continued wide-spread application.  相似文献   
76.
Two patients developed persistent ulcers on the trunk after cutaneous surgery. Both had "chemical" diabetes mellitus. Bacteriologic and histopathologic studies of the ulcers were not revealing of cause. The characteristics of the ulcers are described, and are contrasted with typical lesions of pyoderma gangrenosum and Meleney's postoperative progressive synergistic bacterial gangrene. We believe these patients had variant lesions of pyoderma gangrenosum.  相似文献   
77.
Our preliminary studies suggested that the novel gag-truncated mos (tmos) open reading frame (ORF) of R7, a spontaneous deletion mutant of Moloney murine sarcoma virus 124 (MoMuSV124), may be responsible for R7's unique ability to induce brain lesions in all R7-injected mice. However, when we replaced the gag-tmos ORF with either the MoMuSV124 or the homologous myeloproliferative sarcoma virus env-mos gene, we found that both recombinant viruses also induced brain lesions in all injected mice. Although these studies suggested that the critical determinants for brain lesion induction may reside in the tmos sequence common to all three viruses, they did not demonstrate if the N-terminus of Mos was dispensable for this activity. By inserting the FLAG sequence at the 3' end of the R7 gag-tmos ORF, we demonstrated that R7 does synthesize a Gag-tMos fusion protein. Using R7 gag deletion mutants with and without the FLAG sequence, we further demonstrated that (i) deletion of the entire gag sequence abolished R7's transforming activity; (ii) the ability of the virus to transform cultured NIH/3T3 cells was significantly reduced only when most of gag was deleted; (iii) the ability of the virus to induce brain lesions was inversely proportional to the extent of its gag deletions; and (iv) the insertion of FLAG at the Mos C-terminus did not reduce the in vitro transforming activity of the FLAG-tagged viruses but did reduce their ability to induce brain lesions. Thus, we have demonstrated that altering the N- or C-terminus of the R7 Gag-tMos fusion protein can affect disease manifestation.  相似文献   
78.
79.
Digital data from 3‐D treatment planning computers is generally used for patient planning and then never considered again. However, such data contains enormous quantities of information regarding patient geometries, tissue outlining, treatment approaches and dose distributions. Were such data accessible from planning systems from multiple manufacturers, there would be substantial opportunities for undertaking quality assurance of radiotherapy clinical trials, prospective assessment of trial outcomes and basic treatment planning research and development. The technicalities of data exchange between planning systems are outlined, and previous attempts at producing systems capable of viewing and/or manipulating imaging and radiotherapy digital data reviewed. Development of a software system for enhancing the quality of Australasian clinical trials is proposed.  相似文献   
80.
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