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991.
Objective: To investigate the mRNA and protein expression of FK506-binding protein 52 (FKBP52) in the chorionic villi of patients with recurrent spontaneous abortion (RSA) and normal women during early pregnancy.

Methods: Fresh chorionic villus tissues were collected from 60 subjects. A total of 30 patients with a history of RSA were enrolled into the RSA group and 30 normal pregnant women were enrolled into the control group. The FKBP52 mRNA expression levels in chorionic villi of the RSA patients and healthy controls were measured via semiquantitative RT-PCR. The protein distribution and expression levels of FKBP52 in chorionic villi were analyzed through immunohistochemistry (IHC). The correlation between FKBP52 expression and RSA was analyzed.

Results: We demonstrated that FKBP52 mRNA is expressed in chorionic villi samples of normal pregnancy and RSA. RSA patients exhibited significantly lower FKBP52 gene expression levels compared with those in normal pregnancies (p?<?0.05). FKBP52 immunoreactivity in chorionic villi was mainly observed in trophoblast cell cytoplasm. The FKBP52 protein expression levels in the chorionic villi of RSA patients was significantly lower than in normal women during pregnancy (p?<?0.05).

Conclusions: FKBP52 protein levels were decreased in the chorionic villi of RSA patients, which indicate that the decrease in FKBP52 may be associated with RSA. The low FKBP52 mRNA expression level, which is consistent with the IHC result, may affect embryonic development and even lead to abortion. FKBP52 may be involved in the pathogenesis of RSA and new therapies that increase the FKBP52 expression may help treat RSA.  相似文献   

992.
Previous study has revealed that chromium malate could improve insulin resistance and the regulation of fasting blood glucose in type 2 diabetic rats. This study was designed to investigate the effect of chromium malate on hypoglycemic and improve insulin resistance activities in 3T3-L1 adipocytes with insulin resistance and investigate the acting mechanism. The result indicated that chromium malate exhibited direct hypoglycemic activity in vitro. Compared with the model group, chromium malate could significantly promote the expression levels of GLUT-4, Akt, Irs-1, PPARγ, PI3K and p38-MAPK and their mRNA, increase p-AKT/AKT level, AKT and AMPKβ1 phosphorylation and reduce Irs-1 phosphorylation and p-Irs-1/Irs-1 level in 3T3-L1 adipocytes (p < 0.05). Chromium malate is more effective in regulating the proteins and mRNA expressions than those of chromium trichloride and chromium picolinate. Compared to the model group, pretreatment with the specific p38-MAPK inhibitor completely inhibited the GLUT-4 and Irs-1 proteins and mRNA expressions induced by the chromium malate. In conclusion, chromium malate had a beneficial influence on improvement of controlling glucose levels and insulin resistance in 3T3-L1 adipocytes with insulin resistance by regulating proteins productions and genes expressions in glucose uptake and insulin sensitivity signaling pathways.

Chromium malate could increase the related protein and mRNA levels in 3T3-L1 adipocytes with insulin resistant. Pretreatment with the inhibitor completely/partially inhibited the GLUT-4 and Irs-1 proteins and mRNA expression compared to model group.  相似文献   
993.
In this work, mesoporous Ni–Co composite oxides were synthesized by a facile liquid-precipitation method without the addition of surfactant, and their ability to catalyse a low temperature CO oxidation reaction was investigated. To explore the effect of the synergetic interaction between Ni and Co on the physicochemical properties and catalytic performance of these catalysts, the as-prepared samples were characterized using XRF, XRD, LRS, N2-physisorption (BET), SEM, TEM, XPS, H2-TPR, O2-TPD and in situ DRIFTS characterization techniques. The results are as follows: (1) the doping of cobalt can reduces the size of NiO, thus massive amorphous NiO have formed and highly dispersed on the catalyst surface, resulting in the formation of abundant surface Ni2+ ions; (2) Ni2+ ions partially substitute Co3+ ions to form a Ni–Co spinel solid solution, generating an abundance of surface oxygen vacancies, which are vital for CO oxidation; (3) the Ni0.8Co0.2 catalyst exhibits the highest catalytic activity and a satisfactory stability for CO oxidation, whereas a larger cobalt content results in a decrease in activity, suggesting that the amorphous NiO phase is the dominant active phase instead of Co3O4 for CO oxidation; (4) the introduction of Co can alter the morphology of catalyst from plate-like to flower-like and then to dense granules. This morphological variation is related to the textural properties and catalytic performance of the catalysts. Lastly, a possible mechanism for CO oxidation reaction is tentatively proposed.

The flower-like catalyst possesses highly dispersed amorphous NiO and a high concentration of surface oxygen vacancies which are the central points for CO oxidation.  相似文献   
994.
To solve the problem of contamination of hexavalent chromium (Cr(vi)), visible-light-driven graphene-based ternary metal chalcogenide nanosheets (rGO/SnIn4S8) were synthesized via a one-pot surfactant-assisted hydrothermal method for the photoreduction of Cr(vi). Characterizations demonstrated that SnIn4S8 nanosheets were uniformly distributed on the surface of rGO and the as-synthesized nanosheets exhibited excellent photocatalytic activity under visible light. In addition, the effects of pH, concentration of critic acid, holes and electron scavengers on the reduction of Cr(vi) were systematically investigated. It was found that 50 mg L−1 of Cr(vi) could be completely removed within 30 min at pH 2 when citric acid served as a hole scavenger. Kinetic studies showed that the photocatalytic reduction of Cr(vi) processes obeyed the pseudo first order model. Further study indicated that the Cr(iii) species was immediately adsorbed onto the surface of the rGO/SnIn4S8 nanosheets after photocatalytic reduction of Cr(vi). Additionally, recycling results suggested that rGO/SnIn4S8 nanosheets possessed high recycle ability and stability after repeated use (5 times). This effective and promising work might provide a new strategy for the photoreduction of Cr(vi) and complete removal of chromium from effluent through the novel photocatalyst rGO/SnIn4S8.

Fabrication of visible-light-responsive photocatalyst (rGO/SnIn4S8) for photoreduction of Cr(vi) and adsorption of Cr(iii).  相似文献   
995.
Correction for ‘Synthesis, and single crystal structure of fully-substituted polynitrobenzene derivatives for high-energy materials’ by Wei Yang et al., RSC Adv., 2018, 8, 2203–2208.

The literature citation to molecule 1 in Scheme 1 was in error and should have been to ref. 8; the corrected Scheme 1 is attached.Open in a separate windowScheme 1Synthetic strategy of polynitrobenzene derivatives for energetic materials.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
996.
People who identify as members of religious communities, such as the Amish and Low German Mennonites, face challenges obtaining quality health care and engagement in research due in part to stereotypes that are conveyed through media and popular discourses. There is also a growing concern that even when these groups are engaged in research, the guiding frameworks of the research fail to consider the sociocultural or historical relations of power, further skewing power imbalances inherent in the research relationship. This paper aims at discussing the uses of cultural safety in the context of health research and knowledge translation with groups of people that are associated with a specific religion. Research with the Amish and Low German Mennonites is provided as examples to illustrate the use of cultural safety in this context. From these examples, we discuss how the use of cultural safety, grounded in critical theoretical perspectives, offers new insight into health research with populations that are traditionally labeled as minority, vulnerable, or marginalized, especially when a dominant characteristic is a unique religious perspective.  相似文献   
997.
Objectives: To assess how cigarette smoking affects health care utilization among rural residents in China and to analyze the choice of health facility among current and former smokers in rural China.

Methods: This study employed three waves (2010–2014) of the China Family Panel Studies. The data set included 10,330 adults in each wave. Fixed effect and random effect logistic models and multinomial logistic model were used for data analysis.

Results: First, according to the fixed effect logistic model, the results showed that current and former smokers are positively (ORs > 1) and significantly associated with outpatient care. Moreover, former smokers are positively (ORs > 1) and significantly associated with inpatient utilization. Second, based on the random effect logistic model, the results illustrated that heavy smokers and long-term quitters are positively (ORs > 1) and significantly related to outpatient care, and former smokers are positively (ORs > 1) and significantly associated with inpatient utilization.

Conclusions: Firstly, the present study found that current and former smokers use more outpatient care than non-smokers. Moreover, former smokers use more inpatient care than non-smokers. Secondly, former smokers use more inpatient care than non-smokers, long-term quitters decrease the probability of using inpatient care compared with recent and moderate-term quitters.  相似文献   

998.
999.
针对临床专业型研究生和医学影像学科特点,在传统实践教学的基础上,引入医学图像存档与传输系统(picture archiving and communicating system, PACS),并通过实行“导师制”、开展小讲座及借助以问题为基础的学习形式应用于出科考试,提高了学生轮转实习效果。  相似文献   
1000.
教师教学能力是教师专业知识技能及个人素养的综合体现,与教学效果紧密相关。中医骨伤科学教师教学能力主要在临床工作和教学实践中养成,反映其课堂授课及临床带教效率和质量,其构成要素应从专业素养、教学设计能力、现代教育技术素养和敬业精神等方面加以强化。  相似文献   
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