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101.
离子注入技术是将某种元素的原子进行电离,并使其在电场中加速,在获得较高的速度后射入固体材料表面。在离子注入过程中,被电离的离子在电场作用下加速运动,离子靠着本身获得的动能进入基体表面,在表层中运动的离子与基体原子作用损失能量后在一定的位置停留下来。该技术自60年代问世以来,主要用于材料改性等方面。80年代中期,我国学者开始将其用于农作物育种方面的研究,大大拓宽了离子注入技术的应用领域。所用实验材料的基因及表现型见Tab3,我们将氢离子(E=35MeV)注入处于胚胎发育后期的家蚕卵内(Tab1),观察其对家蚕形态及遗传方面的影响,结果表明:(1)在家蚕胚胎发育的已4期注入氢离子,其半致死剂量LD50为1x1010~1x1011cm2这一区间之内;当剂量达到1x1012cm2时,已全部致死(Fig.1&Tab.2);(2)注入氢离子能够使家蚕在第1腹节上产生褐斑(Fig.2)的频率增高。并首次观察到因注入氢离子而导致家蚕出现非成对的褐斑(Fig.3&Tab.4)。(3)在氢离子注入剂量为1x1010cm2时,能够诱变产生大量的嵌合体家蚕,并且诱变频率高达38.5%(Fig.4&Tab.5),这样高的  相似文献   
102.
Exosomes are 40–100 nm nano-sized vesicles that are released from many cell types into the extracellular space. Such vesicles are widely distributed in various body fluids. Recently,m RNAs and micro RNAs(mi RNAs) have been identified in exosomes, which can be taken up by neighboring or distant cells and subsequently modulate recipient cells. This suggests an active sorting mechanism of exosomal mi RNAs, since the mi RNA profiles of exosomes may differ from those of the parent cells. Exosomal mi RNAs play an important role in disease progression, and can stimulate angiogenesis and facilitate metastasis in cancers. In this review, we will introduce the origin and the trafficking of exosomes between cells, display current research on the sorting mechanism of exosomal mi RNAs, and briefly describe how exosomes and their mi RNAs function in recipient cells.Finally, we will discuss the potential applications of these mi RNA-containing vesicles in clinical settings.  相似文献   
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In apple cultivation, simulation models may be used to monitor fruit size during the growth and development process to predict production levels and to optimize fruit quality. Here, Fuji apples cultivated in spindle-type systems were used as the model crop. Apple size was measured during the growing period at an interval of about 20 days after full bloom, with three weather stations being used to collect orchard temperature and solar radiation data at different sites. Furthermore, a 2-year dataset (2011 and 2012) of apple fruit size measurements were integrated according to the weather station deployment sites, in addition to the top two most important environment factors, thermal and sunshine hours, into the model. The apple fruit diameter and length were simulated using physiological development time (PDT), an indicator that combines important environment factors, such as temperature and photoperiod, as the driving variable. Compared to the model of calendar-based development time (CDT), an indicator counting the days that elapse after full bloom, we confirmed that the PDT model improved the estimation accuracy to within 0.2 cm for fruit diameter and 0.1 cm for fruit length in independent years using a similar data collection method in 2013. The PDT model was implemented to realize a web-based management information system for a digital orchard, and the digital system had been applied in Shandong Province, China since 2013. This system may be used to compute the dynamic curve of apple fruit size based on data obtained from a nearby weather station. This system may provide an important decision support for farmers using the website and short message service to optimize crop production and, hence, economic benefit.  相似文献   
105.
Genexol-PM, produced by Samyang Company (Korea) is an excellent preparation of paclitaxel (PTX) for clinical cancer treatment. However, it cannot resolve the issue of multidrug resistance (MDR)—a significant problem in the administration of PTX to cancer patients. To increase the efficacy of Genexol-PM against MDR tumors, a mixed micelle capable of serving as a vehicle for PTX was developed, and two substances were chosen as carrier materials: 1) Polyethylene glycol–polylactic acid (PEG-PLA), the original vehicle of Genexol-PM. 2) Vitamin E-TPGS, an inhibitor of P-glycoprotein (P-gp). P-gp has been proven to be the main cause of MDR. In vitro evaluation indicated that the mixed micelle was an ideal PTX delivery system for the treatment of MDR tumors; the mixed micelle also showed a significantly better drug-loading coefficient than Genexol-PM.  相似文献   
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To evaluate the frequency and clinicopathological features of ROS1 and RET rearrangements in N2 node positive stage IIIA (IIIA-N2) non-small cell lung cancer (NSCLC) patients, we retrospectively screened 204 cases with a tissue microarray (TMA) panel by fluorescent in situ hybridization (FISH), and confirmed by direct sequencing and immunohistochemistry (IHC). The relationship between ROS1 or RET rearrangements, clinicopathological features, and prognostic factors were analyzed in resected stage IIIA-N2 NSCLC. Of the 204 cases, 4 cases were confirmed with ROS1 rearrangement, but no RET rearrangement was detected. All 4 ROS1-rearranged cases were adenocarcinomas. The predominant pathological type was acinar pattern in ROS1-rearranged tumors, except for 1 case harboring a mixture acinar and mucous tumor cells. Variants of ROS1 rearrangement were SDC4-ROS1 (E2:E32), SDC4-ROS1 (E4:E32) and SDC4-ROS1 (E4:E34). There was no significant association between ROS1 rearrangement and clinicopathological characteristics. In this cohort, multivariate analysis for overall survival (OS) indicated that squamous cell carcinoma and lobectomy were independent predictors of poor prognosis; R0 surgical resection and non-pleural invasion were independent predictors of good prognosis. In resected stage IIIA-N2 NSCLC patients, ROS1-rearranged cases tended to occur in younger patients with adenocarcinomas. The prognosis of resected stage IIIA-N2 is generally considered poor, but patients with ROS1 rearrangement will benefit from the targeted therapy.  相似文献   
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Background

The coronary artery calcification (CAC) is clinically considered as one of the important predictors of atherosclerosis. Several studies have confirmed that endothelin-1(ET-1) plays an important role in the process of atherosclerosis formation. The aim of this study was to investigate whether big ET-1 is associated with CAC.

Methods and Results

A total of 510 consecutively admitted patients from February 2011 to May 2012 in Fu Wai Hospital were analyzed. All patients had received coronary computed tomography angiography and then divided into two groups based on the results of coronary artery calcium score (CACS). The clinical characteristics including traditional and calcification-related risk factors were collected and plasma big ET-1 level was measured by ELISA. Patients with CAC had significantly elevated big ET-1 level compared with those without CAC (0.5±0.4 vs. 0.2±0.2, P<0.001). In the multivariate analysis, big ET-1 (Tertile 2, HR = 3.09, 95% CI 1.66–5.74, P <0.001, Tertile3 HR = 10.42, 95% CI 3.62–29.99, P<0.001) appeared as an independent predictive factor of the presence of CAC. There was a positive correlation of the big ET-1 level with CACS (r = 0.567, p<0.001). The 10-year Framingham risk (%) was higher in the group with CACS>0 and the highest tertile of big ET-1 (P<0.01). The area under the receiver operating characteristic curve for the big ET-1 level in predicting CAC was 0.83 (95% CI 0.79–0.87, p<0.001), with a sensitivity of 70.6% and specificity of 87.7%.

Conclusions

The data firstly demonstrated that the plasma big ET-1 level was a valuable independent predictor for CAC in our study.  相似文献   
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