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61.
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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目的:观察二乙酰基莲心碱拮抗氯化钾、乙酰胆碱(Ach)和组胺(His)所致猪冠状动脉条收缩的作用.方法:离体平滑肌实验方法,观察二乙酰基莲心碱对氯化钾,Ach,His所致猪冠状动脉条收缩曲线的影响以及在无钙克氏液中,对His引起猪冠状动脉条第一相收缩和钙引起第二相收缩的影响.结果:不同剂量二乙酰基莲心碱可使氯化钾,Ach,His所致冠脉条收缩量效曲线呈非竞争性拮抗作用,对冠脉条第一相和第二相收缩都有明显的抑制作用结论:二乙酰基莲心碱具有扩张冠脉的作用,此作用与拮抗细胞内钙的释放和抑制外钙内流有关.  相似文献   
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Total talar extrusion without a soft tissue attachment is an extremely rare injury and is rarely reported. Appropriate treatment remains controversial. We describe the long-term outcomes of two patients who had complete talar extrusion without remaining soft tissue attachment treated with arthrodesis. Both of our patients had complications such as infection and progressive osteolysis. We suggest reimplantation of the extruded talus after thorough debridement as soon as possible as a reasonable option unless the talus is contaminated or missing, because an open wound may arise from inside to outside.  相似文献   
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Pattern hair loss (PHL) is the most common form of baldness in both sexes. The Norwood–Hamilton classification is the most commonly used classification worldwide, but it has many limitations. The basic and specific (BASP) classification was introduced as an improvement over the Norwood–Hamilton classification. Previous research was done to estimate the reliability of the Norwood–Hamilton classification and the result was unsatisfactory. However, the reliability of the BASP and Norwood–Hamilton classifications has not yet been compared. Eight dermatological specialists, 17 dermatological residents and 15 general physicians classified PHL in 100 sets of photographs using both the BASP and Norwood–Hamilton classifications. Intergroup reproducibility was evaluated by examining the match rate of the individual data in each group and the match rate between hair specialist and the other examiners. Intragroup repeatability was determined by calculating the match rate between the first and second studies. In terms of intergroup reproducibility of the match rate for individual data in each group, the basic type had the best agreement, the specific type had the second best, and the Norwood–Hamilton classification had the lowest match rate. In comparison, hair specialist and intragroup repeatability showed the same patterns. The BASP classification not only distinguishes all kinds of hair loss patterns, but also has better reproducibility and repeatability than the Norwood–Hamilton classification.  相似文献   
67.
This study describes a retrospective analysis on the transplant outcome of 56 consecutive patients with myelodysplastic syndrome (MDS) according to their response to hypomethylating agents (HMA). While 2‐yr disease‐free survival (DFS) of patients who transformed to acute myeloid leukemia (= 12) was 25%, that of the remaining patients with MDS according to response to HMA was 73.1%, 68.1%, 50.0%, and 20.8% in G‐COR (group of continuous response, = 19), G‐NoC (group of no change, = 15), G‐LOR (group of loss of response, = 6), and G‐DP (group of disease progression, = 4), respectively. When dichotomized as G‐COR/G‐NoC versus G‐LOR/G‐DP, significantly different 2‐yr DFS (71.0% vs. 33.3%; = 0.004) and relapse (14.1% vs. 46.7%; = 0.016) were demonstrated. On multivariate analysis, G‐LOR/G‐DP [hazard ratio (HR), 3.91; = 0.008] and poor karyotype at transplantation (HR, 2.69; = 0.017) were the significant predictors for poor DFS, as G‐LOR/G‐DP was for relapse (HR, 6.28; = 0.011). DFS was significantly poor in patients with any of the two predictors in all MDS (81.5% vs. 34.9%; = 0.001) or higher‐risk MDS (HrMDS) at the time of HMA (80.7% vs. 29.2%; = 0.005). G‐COR showed a trend of better DFS compared with G‐NoC among HrMDS (74.6% vs. 36.5%; = 0.090). These results implicate the significance of response to HMA on hematopoietic stem cell transplantation (HSCT) outcomes and support the need for future study to verify the suggested strategy of proceeding to transplantation before LOR or DP, especially for HrMDS.  相似文献   
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We proposed a new bacteria patterning method on the restricted region of microbeads, using the submerged property of polystyrene microbeads on various concentrations of agarose gel. Moreover, we fabricated a bacterial microrobot using attenuated Salmonella typhimurium through the new patterning methods. We controlled the submerged degree of polystyrene microbeads through the regulation of the hardness of the agarose gel. The polystyrene microbeads on agarose gel were transferred onto a poly-dimethylsiloxane (PDMS) surface for easy manipulation of the microbeads. Then, we treated the polystyrene microbeads on the PDMS surface with antibacterial adherent factors, such as O2 plasma and bovine serum albumin (BSA). The Salmonella typhimurium was attached to the entire surface of the untreated polystyrene microbeads, whereas Salmonella typhimurium were only attached to the restricted surface region of the treated polystyrene microbeads through the proposed patterning method. The bacteria-attached microbeads gain motility by the propulsion of the attached bacteria, and the selective-bacteria-attached microbeads showed enhanced motility. Compared with whole-bacteria-attached polystyrene microbeads (1.74?±?1.62 μm/s), the selective bacteria-attached polystyrene microbeads, using O2 plasma and BSA, showed 9.18?±?1.88 μm/s and 14.65?±?8.66 μm/s faster moving velocities, respectively. Through the results, we expected that the proposed patterning methodology of microbeads could contribute to the development of biomedical bacterial microrobots.  相似文献   
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