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Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献
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Carbonic anhydrase IX expression predicts outcome of interleukin 2 therapy for renal cancer. 总被引:4,自引:0,他引:4
Michael Atkins Meredith Regan David McDermott James Mier Eric Stanbridge Amanda Youmans Philip Febbo Melissa Upton Mirna Lechpammer Sabina Signoretti 《Clinical cancer research》2005,11(10):3714-3721
PURPOSE: Renal cancer response to interleukin 2 (IL-2) therapy and patient survival has been correlated with tumor histology and carbonic anhydrase IX (CAIX) expression. In an effort to confirm and expand these observations, we examined CAIX expression in pathology specimens from renal cancer patients who had previously received IL-2 therapy. EXPERIMENTAL DESIGN: Paraffin-embedded tissue sections of renal cancer were immunostained with the MN-75 monoclonal antibody to CAIX and expression levels were correlated with histologic findings and clinical outcome. RESULTS: Tissue specimens were obtained from 66 patients; 27 of whom (41%) had responded to IL-2-based therapy. Fifty-eight specimens were assessed as clear cell, with 56, 33, and 4 having alveolar, granular, and papillary features, respectively. Twenty-four (36%), 31 (47%), and 11 (17%) were classified into good, intermediate, and poor prognosis groups according to the Upton pathology model. Forty-one specimens (62%) had high CAIX expression. Twenty-one of 27 (78%) responding patients had high CAIX expressing tumors compared with 20 of 39 (51%) nonresponders (odds ratio, 3.3; P = 0.04). Median survival was prolonged (P = 0.04) and survival >5 years was only seen in high CAIX expressers. In patients with intermediate pathologic prognosis, all nine responders had high CAIX expression versus 11 of 22 nonresponders. A resultant group with good pathologic prognosis alone or with intermediate pathologic prognosis and high CAIX contained 26 of 27 (96%) responders compared with 18 of 39 (46%) nonresponders (odds ratio, 30; P < 0.01) and exhibited longer median survival (P < 0.01). CONCLUSIONS: CAIX expression seems to be an important predictor of outcome in renal cell carcinoma patients receiving IL-2-based therapy and may enhance prognostic information obtained from pathology specimens. 相似文献
84.
Periodicity in orientation discrimination and the unconfounding of visual information 总被引:2,自引:0,他引:2
Orientation discrimination is a periodic function of mean orientation. Discrimination sensitivity (i.e. threshold-1) was measured at 7.5 deg increments around the clock for an 8 c/deg grating subtending 1.0 deg dia located 1.25 deg from the foveal centre. Discrimination sensitivity was best for horizontal and vertical orientations, but did not fall monotonically to minima at 45 deg and 135 deg. Instead it fell precipitously to minima at angles of only 20 deg to the horizontal and vertical, and there was a weak submaximum near 45 deg. This finding is consistent with the proposal that orientation discrimination is determined by the relative activity of broadly-tuned, orientation-sensitive neural elements, and that only a small number of elements are effective in any small retinal region. This idea can also explain why subjects do not confound a change of orientation with a simultaneous change of contrast or spatial frequency. 相似文献
85.
Dr. Nancy Wanger Nieland MD Ken Hashimoto MD Alfonse T. Masi MD DR PH 《Arthritis \u0026amp; Rheumatology》1972,15(2):193-200
Biopsy specimens of clinically normal skin of 9 consecutive patients with SLE were examined ultrastructurally to determine the presence and frequency of microtubular inclusions. Ten blood vessels were examined in each specimen; every specimen contained at least two positive blood vessels, and some contained 80 to 100% positive vessels. No correlation was found between the frequency of the inclusions and either the disease duration or antinuclear factor titer. The inclusions tended to be more frequent in patients with more acute disease. The absence of inclusions in normal skin may mitigate a diagnosis of SLE. 相似文献
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C.P. Barry C. MacDhabheid K. Tobin L.F. Stassen P. Lennon M. Toner E. O’Regan J.R. Clark 《International journal of oral and maxillofacial surgery》2021,50(8):999-1002
The purpose of this study was to investigate whether the time delay between ‘out of house’ proprietary virtual surgical planning (OH-VSP) of the mandibular resection for oral cancer and the actual surgery results in compromised margins and oncological disadvantage for the patient. Outcomes of patients who had OH-VSP of their mandibular resection and reconstruction were compared with those of patients who had the same surgery using a conventional non-VSP approach. The groups were similar in patient demographics, tumour stage and size, nodal status, and reconstruction complexity. VSP resulted in a significant reduction in operating time (P < 0.01). VSP did not affect bony (P = 0.49) or soft tissue (P = 0.22) margin status. In summary, VSP reduced the operating theatre time, and despite the time interval between bony resection planning and surgery, there was no compromise to the oncological safety of the operation. 相似文献
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