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151.
Zhejiang province, China, has implemented a population based, real-time surveillance system that tracks acute cardiovascular diseases (CVDs) events since 2001. This study aimed to describe the system and report CVD incidence, mortality and case-fatality between urban and rural areas in Zhejiang in 2012. The surveillance system employs a stratified random sampling method covering all permanent residents of 30 counties/districts in Zhejiang. Acute CVD events such as coronary heart disease (CHD) and stroke were defined, registered and reviewed based on the adapted MONICA (Monitoring Trends and Determinants in Cardiovascular Disease) definitions. Data were collected from health facilities, vital registries, supplementary surveys, and additional investigations, and were checked for data quality before input in the system. We calculated the rates and compared them by gender, age and region. In 2012, the incidence, mortality and case-fatality of total acute CVD events were 367.0 (CHD 59.1, stroke 307.9), 127.1 (CHD 43.3, stroke 83.8) per 100,000 and 34.6% (CHD 73.2%, stroke 27.2%), respectively. Compared with rural areas, urban areas reported higher incidence and mortality but lower case-fatality rates for CHD (P<0.001), while lower incidence but higher mortality and case-fatality rates for stroke (P<0.001). We found significant differences on CHD and stroke epidemics between urban and rural areas in Zhejiang. Special attentions need to be given to stroke control, especially in rural areas.  相似文献   
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153.
Uridine diphosphate-glucose dehydrogenase (UGD, EC1.1.1.22 oxidizes UDP-Glc (UDP-D-glucose) to UDP-GlcA (UDP-Dglucuronate), a critical precursor of cell wall polysaccharides. GbUGD6 from Gossypium barbadense is more highly expressed late in the elongation of cotton fibers (15 d post-anthesis (DPA)) and during the stage of secondary cell wall thickening (30 DPA). Subcellular localization analysis in onion epidermis revealed that fluorescently labeled GbUGD6 protein was distributed throughout the cell membrane, as well as the nucleus and vacuoles. Examination of UGD function in Arabidopsis revealed that the antisense GbUGD6 lines had shorter roots, deferred blossoming, compared to wild-type plants. Activities of associated enzymes were also affected by UGD reduction, and biochemical analysis of cell wall samples showed an increase in cellulose levels and a decrease in UGP-GlcA contents. The results of the present study as well as previous studies on UGD support the conclusion that UGD plays a major role in synthesizing polysaccharides synthesis in the cell wall.  相似文献   
154.
Chenopodium ambrosioides L. can tolerate high concentrations of manganese and has potential for its use in the revegetation of manganese mine tailings. Following a hydroponic investigation, transmission electron microscopy (TEM)-energy disperse spectroscopy (EDS) was used to study microstructure changes and the possible accumulation of Mn in leaf cells of C. ambrosioides in different Mn treatments (200, 1000, 10000 μmol·L?1). At 200 μmol·L?1, the ultrastructure of C. ambrosioides was clearly visible without any obvious damage. At 1000 μmol·L?1, the root, stem and leaf cells remained intact, and the organelles were clearly visible without any obvious damage. However, when the Mn concentration exceeded 1000 μmol·L?1 the number of mitochondria in root cells decreased and the chloroplasts in stem cells showed a decrease in grana lamellae and osmiophilic granules. Compared to controls, treatment with 1000 μmol·L?1 or 10000 μmol·L?1 Mn over 30 days, gave rise to black agglomerations in the cells. At 10000 μmol·L?1, Mn was observed to form acicular structures in leaf cells and intercellular spaces, which may be a form of tolerance and accumulation of Mn in C. ambrosioides. This study has furthered the understanding of Mn tolerance mechanisms in plants, and is potential for the revegetation of Mn-polluted soils.  相似文献   
155.
A series of SrMoO4:Sm3+,Tb3+,Na+ phosphors was synthesized using a high‐temperature solid‐state reaction method in air. On excitation at 290 nm, SrMoO4:Sm3+,Tb3+ phosphor emitted light that varied systematically from green to reddish‐orange on changing the Sm3+ and Tb3+ ion concentrations. The emission intensities of SrMoO4:Sm3+ and SrMoO4:Sm3+,Tb3+ phosphors were increased two to four times due to charge compensation when Na+ was added as a charge compensator. The luminescence mechanism and energy transfer could be explained using energy‐level diagrams of the MoO42– group, Sm3+ and Tb3+ ions. SrMoO4:Sm3+,Tb3+,Na+ could be used as reddish‐orange phosphor in white light‐emitting diodes (LEDs) based on an ~ 405 nm near‐UV LED chip. This research is helpful in adjusting and improving the luminescence properties of other phosphors. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
156.
Autophagy plays important roles in self-renewal and differentiation of stem cells. Hepatic progenitor cells (HPCs) are thought to have the ability of self-renewal as well as possess a bipotential capacity, which allows them to differentiate into both hepatocytes and bile ductular cells. However, how autophagy contributes to self-renewal and differentiation of hepatic progenitor cells is not well understood. In this study, we use a well-established rat hepatic progenitor cell lines called WB-F344, which is treated with 3.75 mM sodium butyrate (SB) to promote the differentiation of WB-F344 along the biliary phenotype. We found that autophagy was decreased in the early stage of biliary differentiation, and maintained a low level at the late stage. Activation of autophagy by rapamycin or starvation suppressed the biliary differentiation of WB-F344. Further study reported that autophagy inhibited Notch1 signaling pathway, which contributed to biliary differentiation and morphogenesis. In conclusions, autophagy regulates biliary differentiation of hepatic progenitor cells through Notch1 signaling pathway.  相似文献   
157.
Glaucoma is one of the leading eye diseases due to the death of retinal ganglion cells. Increasing evidence suggests that retinal Müller cells exhibit the characteristics of retinal progenitor cells and can differentiate to neurons in injured retinas under certain conditions. However, the number of ganglion cells differentiated from retinal Müller cells falls far short of therapeutic needs. This study aimed to promote the differentiation of retinal Müller cells into ganglion cells by introducing Atoh7 into the stem cells dedifferentiated from retinal Müller cells. Rat retinal Müller cells were isolated and dedifferentiated into stem cells, which were transfected with PEGFP-N1 or PEGFP-N1-Atoh7 vector, and then further induced to differentiate into ganglion cells. The proportion of ganglion cells differentiated from Atoh7-tranfected stem cells was significantly higher than that of control transfected or untransfected cells. In summary, Atoh7 promotes the differentiation of retinal Müller cells into retinal ganglion cells. This may open a new avenue for gene therapy of glaucoma by promoting optic nerve regeneration.  相似文献   
158.
Chronic obstructive pulmonary disease(COPD), lung cancer(LC) and tuberculosis(TB) are common chronic lung diseases that generate a large disease burden and significant health care resource use in China. The aim of this study was to quantify spatial patterns and effects of air pollution and meteorological factors on hospitalization of COPD, LC and TB in Beijing. Daily counts of hospitalization for 2010 were obtained from the Beijing Urban Employees Basic Medical Insurance(UEBMI) system.Bayesian hierarchical Poisson regression models were applied to identify spatial patterns of hospitalization for COPD, LC and TB at the district level and explore associations with inhalable particulate matter(aerodynamic diameter 10 μm, PM_(10)), sulfur dioxide(SO_2), nitrogen dioxide(NO_2), mean temperature and relative humidity. There were 18,882, 14,295 and 2,940 counts of hospitalizations for COPD, LC and TB respectively, in Beijing in 2010. Clusters of high relative risk were in different locations for the three diseases. The effect of relative humidity on COPD hospitalization was most significant with a relative risk(RR) of 1.070(95%CI: 1.054, 1.086) per one percent increase. For lung cancer hospitalization, exposure to ambient SO_2 was associated with a RR of 1.034(95%CI: 1.011, 1.058) per μg m~(–3) increase. For tuberculosis, the effect of mean temperature was significant with a RR of 1.107(95%CI: 1.038, 1.180) per °C increase. Risk factors and spatial patterns were different for hospitalization of non-infectious and infectious chronic lung disease in Beijing. Even over a short time period(one year), associations were apparent with air pollution and meteorological factors.  相似文献   
159.
Nicorandil exerts myocardial protection through its antihypoxia and antioxidant effects. Here, we investigated whether it plays an anti‐apoptotic role in diabetic cardiomyopathy. Sprague‐Dawley rats were fed with high‐fat diet; then single intraperitoneal injection of streptozotocin was performed. Rats with fasting blood glucose (FBG) higher than 11.1 mmol/L were selected as models. Eight weeks after the models were built, rats were treated with nicorandil (7.5 mg/kg day and 15 mg/kg day respectively) for 4 weeks. H9c2 cardiomyocytes were treated with nicorandil and then stimulated with high glucose (33.3 mmol/L). TUNEL assay and level of bcl‐2, bax and caspase‐3 were measured. 5‐HD was used to inhibit nicorandil. Also, PI3K inhibitor (Miltefosine) and mTOR inhibitor (rapamycin) were used to inhibit PI3K/Akt pathway. The results revealed that nicorandil (both 7.5 mg/kg day and 15mg/kg day) treatment can increase the level of NO in the serum and eNOS in the heart of diabetic rats compared with the untreated diabetic group. Nicorandil can also improve relieve cardiac dysfunction and reduce the level of apoptosis. In vitro experiments, nicorandil (100 µmol) can attenuate the level of apoptosis stimulated by high glucose significantly in H9C2 cardiomyocyte compared with the untreated group. The effect of nicorandil on apoptosis was blocked by 5‐HD, and it was accompanied with inhibition of the phosphorylation of PI3K, Akt, eNOS, and mTOR. After inhibition of PI3K/Akt pathway, the protective effect of nicorandil is restrained. These results verified that as a NO donor, nicorandil can also inhibit apoptosis in diabetic cardiomyopathy which is mediated by PI3K/Akt pathway.  相似文献   
160.
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