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121.
A series of novel ligands for the glucocorticoid receptor containing two heterocycles were synthesized. These compounds were investigated for a dissociative profile using transrepression and transactivation assays. Several compounds were tested in vivo and showed the ability to reduce inflammation in a mouse.  相似文献   
122.
土壤中氨基酸的检测及组成   总被引:2,自引:0,他引:2  
我们采集了江苏省及其他省(区)不同生物、气候条件下的土壤样品,采用同一测试方法研究了表土中的有机氮的变异特征及其影响因素。本文介绍实验土样的酸水介液通过乙酰丙酮──氯仿溶液并调节pH值的方法处理,以除去用色谱法测试土壤中氨基酸的最大干扰物-铁、铝。叙述了土壤中氨基酸检测技术及其组成。  相似文献   
123.
The end products of cellulose metabolism by the trichomonad flagellate Trichomitopsis termopsidis from the termite Zootermopsis sp. were investigated by growing axenic flagellates on [14C]cellulose. The growth of T. termopsidis resulted in the release of label into the supernatant fraction of the culture fluid, and > 75% was volatile under acid conditions. The label was analyzed for 14CO2 and for [14C]volatile compounds by vacuum distillation under acid and alkaline conditions in disposable micro-distillation vessels. The distillate and undistilled culture supernatant fluid were chromatographed on cellulose thin layers to identify the labeled end product. T. termopsidis produced 14CO2 and [14C]acetate which accounted for 25 to 30% and 55 to 60% of the labeled end products, respectively. The ratio of label in CO2 to acetate suggests that they are produced in equimolar amounts. No neutral volatile compounds were produced. The remaining unidentified end product (10 to 20%) was not volatile nor extractable into ether. Hydrogen was produced by T. termopsidis, and the cells were killed by the drug metronidazole. Enzymatic activities were found which account for these end products: pyruvate:ferredoxin oxidoreductase and hydrogenase. The results indicate that acetate is the end product of T. termopsidis cellulose metabolism and is available to the termite for energy metabolism and biosynthesis.  相似文献   
124.

Background

To investigate the potential prognostic role of pre-treatment prognostic nutritional index (PNI) in urinary cancers.

Methods

Relevant articles were searched comprehensively from PubMed, Embase and Web of Science, up to November 2018. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted to evaluate their associations.

Result

A total of 12 related articles including 6561 patients were ultimately enrolled. Our results indicated that a relatively lower level of pre-treatment PNI was associated with decreased OS, CSS/DSS and DFS/RFS/PFS (pooled HR?=?1.68, 95% CI 1.45–1.95; pooled HR?=?1.57, 95% CI 1.33–1.86; pooled HR?=?1.75, 95% CI 1.53–1.99, respectively). Subsequent stratified analysis by cancer type for OS showed that PNI could also be a predictor no matter in renal cell cancer (RCC) or bladder cancer (BC) (pooled HR?=?1.65, 95% CI 1.37–1.97 and pooled HR?=?1.67, 95% CI 1.20–2.33). Similar results could be found in DFS/RFS/PFS (RCC: HR?=?1.81, 95% CI 1.54–2.13 and BC: HR?=?1.68, 95% CI 1.32–2.12) and in CSS/DSS (RCC: HR?=?1.50, 95% CI 1.23–1.82 and upper tract urothelial carcinoma: HR?=?1.61, 95% CI 1.13–2.28). As for the treatment subgroup, a relatively lower level of PNI could also be a positive predictor for OS (surgery: HR?=?1.64, 95% CI 1.40–1.93; target therapy: HR?=?1.88, 95% CI 1.34–2.63) and DFS/RFS/PFS (surgery: HR?=?1.69, 95% CI 1.47–1.95; target therapy: HR?=?2.14, 95% CI 1.50–3.05).

Conclusion

The outcomes of us shed light on that elevated pre-treatment PNI was positively associated with OS, CSS/DSS and DFS/RFS/PFS, indicating that it could be an independent prognostic factor in urinary cancers.
  相似文献   
125.

Background

The objective of this study was to carry out a systematic review and meta-analysis of embryologic and clinical outcomes following open versus closed vitrification of human oocytes and embryos.

Methods

An electronic literature search was conducted in main electronic databases up to June 30, 2018 using the following key terms: ‘oocyte’, ‘embryo’, ‘blastocyst’, ‘vitrification’, ‘cryopreservation’, ‘device’, ‘survival rate’, ‘pregnancy rate’, etc. A meta-analysis was performed using a random effect model to estimate the value of risk ratios (RRs) and 95% confidence interval (CI). Subgroup analyses and sensitivity analyses were carried out to further confirm the results.

Results

Twelve (Eight prospective and four retrospective) studies comparing open versus closed vitrification of human oocytes or embryos were included. For prospective studies on oocytes, no evidence for a significant difference in cryosurvival rate (RR?=?0.91, 95% CI: 0.80–1.03, P?=?0.14; n?=?2048) or clinical pregnancy rate (RR?=?1.29, 95% CI: 0.80–2.06, P?=?0.30; n?=?150) was observed. Additionally, there were no significant differences between the two methods concerning secondary endpoints included positive βHCG rate, implantation rate, miscarriage rate, ongoing pregnancy rate, live birth rate, cancellation rate, babies born per transferred blastocysts, or multiple birth rate (P?>?0.05). The results of the retrospective studies were similar as the prospective studies.

Conclusions

It is still impossible to conclude that closed vitrification system could be a substitution for open system in human oocyte and embryo cryopreservation based on current evidence. Therefore, more well-designed prospective studies addressing these issues are still warranted.
  相似文献   
126.
Three acceptor–donor–acceptor type nonfullerene acceptors (NFAs), namely, F–F, F–Cl, and F–Br, are designed and synthesized through a halogenation strategy on one successful nonfullerene acceptor FDICTF (F–H). The three molecules show red‐shifted absorptions, increased crystallinities, and higher charge mobilities compared with the F–H. After blending with donor polymer PBDB‐T, the F–F‐, F–Cl‐, and F–Br‐based devices exhibit power conversion efficiencies (PCEs) of 10.85%, 11.47%, and 12.05%, respectively, which are higher than that of F–H with PCE of 9.59%. These results indicate that manipulating the absorption range, crystallinity and mobilities of NFAs by introducing different halogen atoms is an effective way to achieve high photovoltaic performance, which will offer valuable insight for the designing of high‐efficiency organic solar cells.  相似文献   
127.
ICE family proteases have been implicated as important effectors of the apoptotic pathway, perhaps acting hierarchically in a protease cascade. Using cleavage of endogenous protease substrates as probes, three distinct tiers of ICE-like activity were observed after Fas ligation in Jurkat cells. The earliest cleavage detected (30 min) was of fodrin, and produced a 150 kDa fragment. The second phase of cleavage (50 min) involved PARP, U1-70kDa and DNA-PKcs, all substrates of the CPP32-like proteases. Lamin B cleavage was observed during the third cleavage phase (90 min). Distinct inhibition profiles obtained using a panel of peptide-based inhibitors of ICE-like proteases clearly distinguished the three different cleavage phases. These studies provide evidence for a sequence of ICE-like proteolytic activity during apoptosis. The early fodrin cleavage, producing a 150 kDa fragment, identifies an ICE-like activity proximal to CPP32 in Fas-induced Jurkat cell apoptosis.  相似文献   
128.
Wei  Yamin  Wang  Rui  Teng  Junfang 《Neurochemical research》2019,44(7):1613-1620

Ischemic stroke is a leading cause of mortality and morbidity worldwide, and oxidative stress plays a significant role in the ischemia stage and reperfusion stage. Previous studies have indicated that both calcium/calmodulin-dependent protein kinase II (CaMKII) and glucose 6-phosphate dehydrogenase (G6PD) are involved in the oxidative stress. Thus, the aim of this study was to investigate the roles of CaMKIIα, an important isoform of CaMKII, and G6PD in a rat model of middle cerebral artery occlusion (MCAO). Intracerebroventricular injection of small interfering ribonucleic acid (siRNA) for CaMKIIα was performed at 48 h pre-MCAO surgery. Immunofluorescence Staining and western blot were performed to detect the expression of p-CaMKIIα and G6PD in the cortices. 2, 3, 5-Triphenyltetrazolium chloride (TTC) staining was performed to investigate the infarct volume. In addition, neurological deficit, reactive oxygen species (ROS), ratio of reduced-to-oxidized glutathione (GSH/GSSG) and ratio of reduced-to-oxidized oxidized nicotinamide adenine dinucleotide phosphate (NADPH/NADP+) were assessed. The results indicated that both p-CaMKIIα and G6PD were widely located in the neurons and astrocytes, and their expression was gradually increased in the cortices after MCAO, which was accompanied by increased level of ROS and decreased levels of GSH/GSSG and NADPH/NADP+. However, after treatment with siRNA for CaMKIIα, p-CaMKIIα expression was decreased and G6PD expression was increased. Moreover, inhibition of CaMKIIα improved the neurological deficit, reduced the infarct volume, decreased the level of ROS and increased the levels of GSH/GSSG and NADPH/NADP+. The results suggested that CaMKIIα inhibition exerted neuroprotective effects through regulating G6PD expression, which provides a new target for prevention and treatment of stroke.

  相似文献   
129.
An  Tingting  Gao  Yamin  Kuang  Qiqiang  Wu  Yujie  Zaman  Qamar uz  Zhang  Yi  Xu  Bingcheng  Chen  Yinglong 《Plant and Soil》2022,476(1-2):117-131
Plant and Soil - Cadmium (Cd) contamination is a serious threat to plants and humans. Silicon (Si) was reported to have some alleviative effects on Cd stress in plants. However, whether Si...  相似文献   
130.
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