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991.

Background

Ulcerative colitis (UC) impairs the health-related quality of life (HRQOL). The difference in HRQOL between patients with mild and moderately active UC is not well-defined. Few studies have been conducted to explore the factors that influence HRQOL in Chinese patients. Our study aims were to (1) compare HRQOL of mildly active UC patients with moderate patients; (2) explore the factors that influence HRQOL in Chinese patients with UC; and (3) analyze demographic and disease characteristics of UC in China.

Methods

A total of 110 mild and 114 moderate patients with UC were enrolled. The demographic and disease characteristics were recorded. HRQOL was measured by the Chinese version of the inflammatory bowel disease questionnaire (IBDQ) between mild and moderate patients, male and female patients, and different disease distributions. Stepwise regression analysis was used to assess factors influencing the IBDQ score.

Results

Patients with moderate UC had significantly lower IBDQ total scores compared to patients with mild UC (P=0.001). The IBDQ total score had a negative correlation with the Mayo score (r=–0.263, P<0.001). Stepwise regression analysis showed that the disease activity index and gender had an influence on the IBDQ total score (P<0.05). The female patients had a lower score than the male patients (P<0.05), especially in the emotional function domain (P=0.002). Different disease distributions were not statistically significant in the IBDQ total score (P=0.183).

Conclusions

UC has a negative influence on HRQOL. HRQOL in patients with moderate UC was lower than HRQOL in patients with mild UC, as measured by the IBDQ. UC disease activity has a negative correlation with HRQOL. Gender and the disease activity index are important factors involved in the impairment of HRQOL in Chinese patients with UC. Chinese females may benefit from increased psychological care as part of UC therapy.  相似文献   
992.
Water-soluble 2′-O-hydroxypropyltrimethylammoniumchitin chloride (2′-O-HTACCt) was prepared directly from β-chitin and 3-chloro-2-hydroxypropyltrimethylammonium chloride (CTA) in basic medium. The effect of alkali concentration, reaction temperature, reaction time, and dosage of CTA on yield and degree of substitution (DS) of 2′-O-HTACCt were studied. These quaternized chitin derivatives were characterized by FTIR and 1H NMR spectroscopy, conductometric titration, and elemental analysis methods. Research results indicate that β-chitin can react directly with CTA to produce a water-soluble 2′-O-HTACCt derivative with a high DS. The optimal preparation conditions were determined to be 35-40 wt % (aq NaOH), 40 °C (reaction temperature), 6 h (reaction time), and 4 (molar ratio of CTA to β-chitin unit).  相似文献   
993.
994.
Optimization of a lead thiazole amide MF-152 led to the identification of potent bicyclic heteroaryl SCD1 inhibitors with good mouse pharmacokinetic profiles. In a view to target the liver for efficacy and to avoid SCD1 inhibition in the skin and eyes where adverse effects were previously observed in rodents, representative systemically-distributed SCD1 inhibitors were converted into liver-targeting SCD1 inhibitors.  相似文献   
995.
Micro RNAs(mi RNAs) are vital regulators that repress gene expression in the cytoplasm in two main ways: m RNA degradation and translational inhibition. Several animal studies have shown that mi RNAs also target promoters, thereby activating expression.Whether this mi RNA action also occurs in plants is unknown. In this study, we demonstrated that several mi RNAs regulate target promoters in Arabidopsis thaliana. For example, mi R5658 was predominantly present in the nucleus and activated the expression of AT3 G25290 directly by binding to its promoter. Our observations suggest that this mode of action may be a general feature of plant mi RNAs, and thus provide insight into the vital roles of plant mi RNAs in the nucleus.  相似文献   
996.
Plant root development is mediated by the concerted action of the auxin and cytokinin phytohormones, with cytokinin serving as an antagonist of auxin transport. Here, we identify the AUXIN UP-REGULATED F-BOX PROTEIN1 (AUF1) and its potential paralog AUF2 as important positive modifiers of root elongation that tether auxin movements to cytokinin signaling in Arabidopsis (Arabidopsis thaliana). The AUF1 mRNA level in roots is strongly up-regulated by auxin but not by other phytohormones. Whereas the auf1 single and auf1 auf2 double mutant roots grow normally without exogenous auxin and respond similarly to the wild type upon auxin application, their growth is hypersensitive to auxin transport inhibitors, with the mutant roots also having reduced basipetal and acropetal auxin transport. The effects of auf1 on auxin movements may be mediated in part by the misexpression of several PIN-FORMED (PIN) auxin efflux proteins, which for PIN2 reduces its abundance on the plasma membrane of root cells. auf1 roots are also hypersensitive to cytokinin and have increased expression of several components of cytokinin signaling. Kinematic analyses of root growth and localization of the cyclin B mitotic marker showed that AUF1 does not affect root cell division but promotes cytokinin-mediated cell expansion in the elongation/differentiation zone. Epistasis analyses implicate the cytokinin regulator ARR1 or its effector(s) as the target of the SKP1-Cullin1-F Box (SCF) ubiquitin ligases assembled with AUF1/2. Given the wide distribution of AUF1/2-type proteins among land plants, we propose that SCF(AUF1/2) provides additional cross talk between auxin and cytokinin, which modifies auxin distribution and ultimately root elongation.  相似文献   
997.
孤独症是一种病因不明的广泛性发育障碍疾病,它是孤独症谱系障碍的代表疾病,发病年龄早,大多在3岁以内起病,以社会交往障碍,言语交流障碍,动作行为的重复刻板和兴趣范围狭窄为三大临床核心症状。孤独症发病率呈逐年增高趋势,我国患者量已超过一百万。但是迄今为止仍没有特异的方法与手段对孤独症进行彻底有效地诊治,为社会和家庭带来了沉重的负担,因此,其发病机制是迫切需要研究的难题。目前国际上公认为遗传因素在孤独症的发病中起着重要作用,但对于致病基因的确定仍不明确。突触后致密物(PSD)在中枢神经系统神经递质和信息的传递过程中起重要作用,影响学习记忆及认知相关功能,而孤独症患者存在认知相关功能损伤的表现,二者可能存在一定的联系。本文对PSD基因功能以及与孤独症关系的研究加以综述,希望有助于孤独症的病因学研究,以期早日改善该病的诊疗及预防。  相似文献   
998.
Many stem cell populations are tightly regulated by their local microenvironment (niche), which comprises distinct types of stromal cells. However, little is known about mechanisms by which niche subgroups coordinately determine the stem cell fate. Here we identify that Yki, the key Hippo pathway component, is essential for escort cell (EC) function in promoting germline differentiation in Drosophila ovary. We found that Hedgehog (Hh) signals emanating primarily from cap cells support the function of ECs, where Cubitus interruptus (Ci), the Hh signaling effector, acts to inhibit Hippo kinase cascade activity. Mechanistically, we found that Ci competitively interacts with Hpo and impairs the Hpo-Wts signaling complex formation, thereby promoting Yki nuclear localization. The actions of Ci ensure effective Yki signaling to antagonize Sd/Tgi/Vg-mediated default repression in ECs. This study uncovers a mechanism explaining how subgroups of niche cells coordinate to determine the stem cell fate via Hh-Hippo signaling crosstalk, and enhances our understanding of mechanistic regulations of the oncogenic Yki/YAP signaling.  相似文献   
999.
眼斑螳属Creobroter Serville,1839隶属于花螳螂亚科Hymenopodinae。迄今已知19种,主要分布于印度、锡金、泰国、菲律宾、斯里兰卡,印度尼西亚和爪哇,我国已记载2种,分布于四川和广东(梅县)。我们在整理本属标本时,发现二新种及一新记录。新种、新记录记述如后,并列出种检索表。 模式标本均保存在中国科学院上海昆虫研究所。  相似文献   
1000.
In this study, we describe a cell line, Ms-10C, cloned from the line QAU-Ms-E-10 (simplified Ms-10), an embryonic line from Mythimna separata. The cloned cell line was significantly more sensitive to nucleopolyhedrovirus (NPV). Ms-10C cells were mainly spherical with a diameter of 14.42 ± 2.23 μm. DNA amplification fingerprinting (DAF) confirmed the profile of PCR-amplified bands of the cloned cell line was consistent with those of the parental cell line, Ms-10. The sequencing result of the mitochondrial cytochrome c oxidase I (mtCO I) fragment confirmed that the amplified 636-bps mtCOI fragment was 100% identical to that of M. separata. Its chromosomes exhibited the typical characters of lepidopteran cell lines. Its population doubling time was 42.2 h at 27°C. Ms-10C was more sensitive than Ms-10 to both Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and M. separata nucleopolyhedrovirus (MsNPV). At 4 d post infection, the infection rates of two viruses reached 94.2 and 92.3%, respectively. The availability of this cell clone strain will provide a useful tool for the basic research on nucleopolyhedrovirus and for potential application in expression of recombinant proteins with baculovirus expression vector system.  相似文献   
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