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排序方式: 共有1021条查询结果,搜索用时 0 毫秒
1.
Kim  EE; Pjura  G; Lowry  P; Verani  R; Sandler  C; Flechner  S; Kahan  B 《Radiology》1986,159(2):443-446
Serial radionuclide studies using both Tc-99m DTPA (perfusion) and I-131 hippuran (tubular function) were correlated with histologic findings in 25 patients with renal transplants. These cases included 15 cases of cyclosporin-A nephrotoxicity (CsA-NT) and ten cases of acute cellular rejection that were retrospectively selected on the basis of biopsy findings and favorable clinical response to therapy specific for each of these conditions. The serial radionuclide studies enabled the correct diagnosis in 12 of 15 cases of CsA-NT and eight of ten cases of acute rejection. Posttherapy radionuclide studies, furthermore, demonstrated improvement consistent with clinical response. In all cases, the radionuclide results were available at least 24 hours before biopsy findings. These results indicate that serial radionuclide studies evaluating interval changes in both perfusion and tubular function are of significant value in the diagnosis and follow-up of CsA-NT and acute cellular rejection in transplant recipients. This initial experience suggests a sensitivity of 80%.  相似文献   
2.
Cisplatin is a common cause of hypomagnesemia and hypokalemia due to renal magnesium (Mg) and potassium (K) losses. Magnesium plays an important role in the maintenance of intracellular K. An unrecognized and untreated Mg depletion can lead to a refractory K repletion. We describe two patients with hypomagnesemia-associated refractory hypokalemia following cisplatin following cisplatin therapy. Potassium supplementation failed to replace the K deficit. Profound hypokalemia persisted until hypomagnesemia was recognized and corrected. In neither patient was the concurrent hypomagnesemia recognized until the 11th and 9th hospital days. These two cases demonstrated the association of a refractory K repletion and an Mg deficiency. Thus, both serum K ion and Mg levels should routinely be assessed in patients who require cisplatin therapy.  相似文献   
3.
Lee IS  Whang CN  Choi K  Choo MS  Lee YH 《Biomaterials》2002,23(11):2375-2380
Iridium films having near-bulk properties were formed by electron-beam evaporation with simultaneous bombardment of Ar ion beam. The charge-injection capabilities of Ir film were investigated, and the detrusor pressure induced by S2 stimulation with Ir-coated Pt electrode was measured and compared with the uncoated Pt electrode. The charge densities of Ir film were continuously increased with increase in the number of cycles in 0.1 M H2SO4 due to the accumulation of the iridium oxide phase. The iridium oxide formed contained nano-pores, and oxides had different dielectric properties. The Ir film could inject various amounts of charge in physiological solution under the identical stimulating condition depending on the degree of activation in 0.1 M H2SO4. S2 stimulation by Ir-coated Pt electrode caused more efficient bladder contraction of the male dog than the uncoated Pt electrode under the identical stimulus condition.  相似文献   
4.
Jeong HJ  Whang WK  Kim IH 《Planta medica》1997,63(4):329-334
The studies were carried out to evaluate the constituents in the aerial part of Aconitum chiisanense (Ranunculaceae). From the butanol fraction of the methanol extract, kaempferol 3- O-beta-glucopyranoside-7- O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (I), quercetin 3- O-beta-glucopyranoside-7- O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (II), kaempferol 3- O-beta-glucopyranoside-7- O-(6-trans-feruloyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (III), kaempferol 3- O-beta-glucopyranoside-7- O-(6-benzoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (IV), kaempferol 7- O-(6-trans)-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (V), and kaempferol 7- O-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (VI) were isolated and identified on the basis of their physicochemical and spectroscopic evidence (UV, IR, FAB(-)MS, (1)H-NMR, (13)C-NMR, (1)H- (1)H COSY, HMQC and HMBC). New compounds I-VI were named chiisanin (I), chiiribanin (II), chiiribaconin (III), chiirin (IV), chiiricanin (V), and chiirirhamnin (VI), respectively.  相似文献   
5.
The studies were carried out to evaluate the constituents in the aerial part ofIsodon excisus var.coreanus (Labiatae). From the aqueous fraction of methanol extract, compound 1 (alpha-[[3-(3, 4-dihydroxyphenyl)-1-oxo-2-propenyl]oxy]-3,4-dihydroxy-benzenepropanoic acid), compound II (9-methyl-dihydroferulic acid-4-O-beta-D-glucopyranosyl (1-->2)-alpha-L- rhamnopyranosyl (1-->4)-beta-D-glucopyranoside), compound III (ent-7alpha, 11alpha, 15beta-trihydroxy-kaur-16-en-1-O-beta-D-glucopyranoside) and compound IV (2alpha, 3beta, 7alpha, 23-tetrahydroxy-olean-12-en-28-oic acid 28-O-beta-D-glucopyranoside) were isolated and identified on the basis of their physicochemical and spectroscopic evidences[IR, FAB(-)MS,(1)H-NMR,(13)C-NMR, HMQC,(1)H-(1)H COSY and HMBC (Heteronuclear Multiple Bond Connectivity)]. Especially, New compounds II and III were named isodonin A and Isodonin B respectively.  相似文献   
6.
OBJECTIVES: We explore the policy implications of probabilistic sensitivity analysis in cost-effectiveness analysis by applying simulation methods to a decision model. METHODS: We present the multiway sensitivity analysis results of a study of the cost-effectiveness of vaccination against pneumococcal bacteremia in the elderly. We then execute a probabilistic sensitivity analysis of the cost-effectiveness ratio by specifying posterior distributions for the uncertain parameters in our decision analysis model. In order to estimate probability intervals, we rank the numerical values of the simulated incremental cost-effectiveness ratios (ICERs) to take into account preferences along the cost-effectiveness plane. RESULTS: The 95% probability intervals for the ICER were generally much narrower than the difference between the best case and worst case results from a multiway sensitivity analysis. Although the multiway sensitivity analysis had indicated that, in the worst case, vaccination in the 85 and older age group was not acceptable from a policy standpoint, probabilistic methods indicated that the cost-effectiveness of vaccination was below $50,000 per quality-adjusted life-year in greater than 92% of the simulations and below $100,000 in greater than 95% of the simulations. CONCLUSIONS: Probabilistic methods can supplement multiway sensitivity analyses to provide a more comprehensive picture of the uncertainty associated with cost-effectiveness ratios and thereby inform policy decisions.  相似文献   
7.
A study was carried out to evaluate flavonol glycosides in leaves ofSymplocarpus renifolius (Araceae). From the water fraction of the MeOH extract, three new flavonol glycosides were isolated along with three known compounds, kaempferol-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, quercetin-3-O-β-D-glucopyranosy-l-(1→2)-β-D-glucopyranoside, and caffeic acid. The structures of the new flavonol glycosides were elucidated by chemical and spectral analyses as quercetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, isorhamnetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, and quercetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-(6IIII-trans-caffeoyl)-β-D-glucopyranoside.  相似文献   
8.
Aiming at the development of anticancer agents by modification of phenolic benzo[c]phenanthridine alkaloid, additional hydroxyl group was put on C10 position of fagaridine (1) by a biomimetic synthetic procedure to afford 10-hydroxyfagaridine (12). All of the synthetic intermediates were also screenedin vitro antitumor activities against five different cell lines as well as12. Among them the representative cytotoxic results are shown as follows;p-quinone (11) [ED50 (A549=0.22 μg/ml), (HCT15=0.21 μg/ml), fagaridine (1) (HCT 15=0.41 μg/ml), olefin (6) (HCT 15=0.06 μg/ml), acetal (7) (SKMEL-2=0.07 μg/ml), dihydrofagaridne (10) (A549=0. 38 μg/ml), 10-hydroxyfagaridine (12) (A 549=0.45 μg/ml). From these observation three main remarks can be drawn; (i) the iminium part of benzo[c]phenanthridine is not essential for showing acitvities, (ii) the additional hydroxyl group did not contribute to enhance the cytotoxicity, (iii) the 3-arylisoquinolin-1(2H)-one derivatives were found to display significantin vitro antitumor activity.  相似文献   
9.
Integrin-linked kinase (ILK) facilitates signal transduction between extracellular events and important intracellular survival pathways involving protein kinase B/Akt. We examined the role of ILK in determining pancreatic adenocarcinoma cellular chemoresistance to the nucleoside analogue gemcitabine. Cellular ILK expression was quantified by Western blot analysis. We examined the effects of overexpression of active ILK and of ILK knockdown induced by RNA interference on gemcitabine chemoresistance. We also examined the effects of modulating ILK expression on gemcitabine-induced caspase 3-mediated apoptosis, phosphorylation status of Akt (Ser473) and glycogen synthase kinase. Overexpression of ILK increased cellular gemcitabine chemoresistance, whereas ILK knockdown induced chemosensitization via increased caspase 3-mediated apoptosis. ILK knockdown attenuated Akt Ser473 and glycogen synthase kinase phosphorylation, whereas overexpression of constitutively active myristoylated Akt was sufficient to induce significant recovery in gemcitabine chemoresistance in the presence of ILK knockdown. Levels of ILK expression affect gemcitabine chemoresistance in pancreatic adenocarcinoma cells. This novel finding suggests that therapies directed against ILK and its downstream signaling targets may have the potential to enhance the efficacy of gemcitabine-based chemotherapy.  相似文献   
10.
BackgroundThis study investigated whether the empirical dietary inflammatory index (eDII) score is associated with the inflammatory burden as well as the depressive status in patients with antineutrophil cytoplasmic antibody‐associated vasculitis (AAV).MethodsEighty‐four patients with AAV participated in this study. Birmingham vasculitis activity score (BVAS) and short‐form 36‐item Health Survey mental component summary (SF‐36 MCS) were considered as indices assessing the inflammatory burden and depressive status, respectively. The eDII includes 16 food components and consists of three groups: −9 to −2, the low eDII group; −1 to +1, the moderate eDII group; and +2 to +10, the high eDII group. Furthermore, the lower eDII group includes both the low and moderate eDII groups.ResultsThe median age was 64.5 years (36 men). The eDII scores inversely correlated with SF‐36 MCS (r = −0.298, p = 0.006) but not with BVAS. SF‐36 MCS significantly differ between the lower and higher eDII groups (69.7 vs. 56.7, p = 0.016), but not among the low, moderate and high eDII groups. Additionally, when patients with AAV were divided into two groups according to the upper limit of the lowest tertile of SF‐36 MCS of 55.31, patients in the higher eDII group exhibited a significantly higher risk for the lowest tertile of SF‐36 MCS than those in the lower eDII group (RR 3.000).ConclusionWe demonstrated for the first time that the eDII could predict the depressive status by estimating SF‐36 MCS without utilising K‐CESD‐R ≥ 16 in patients with AAV.  相似文献   
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