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[Objectives] This paper aimed to study the nematicidal activity of the Pseudomonas protegens Pf-5, and to identify the major nematicidal compounds produced by this strain. [Methods] The unmarked deletion mutants of Pf-5 were constructed based on sucrose-induced(sacB gene)lethalality. The model nematodes Caenorhabditis elegans was used as the target. The strains were labeled with green fluorescent protein gene to study the lethal effect of the strain on this nematode. The possible action site of Pf-5 strain was observed by using scanning and transmission electron microscopy. [Results] The Pf-5 strain had strong lethal activity against C. elegans. The LCM of Pf-5 against C. elegans at 48 h and 96 h.was respectively 4.92xl07 CFU·mL-1 and 3.58xlO6 CFU·mL-1. When treated C. elegans with Pf-5 for 48 h, the lethal rate was 73.57%,but when Jit I) gene was knocked out, the lethal activity of PfSufUD was significantly reduced, only 25.04% compared to the wide type. When Delivery domain and CHOPS domain of July gene were respectively deleted, the lethal activity of mutants also significantly decreased. This indicated that the FiteD protein was the major nematicidal substance produced by Pf-5 strain. Scanning electron microscopy showed that Pf-5 strain and its mutant did not destroy the body wall of nematode. But when observed using transmission electron microscopy,the results had showed that the intestinal villi of nematode became thinner, and even fell off, but the mutant Pf-5μfiD didn't have such effect. [Conclusions] The nematicidal substance in the P. protegens Pf-5 strain is the FitD protein,and its site of action is the intestinal tract. [ABSTRACT FROM AUTHOR]

The performance of satellite gravimetry is determined not only by orbital parameters, sensitivity of payloads, resolution of data, et al, but also by inaccuracy of the Earth gravity recovered methods. In past years, the performance analysis results were unavoidably affected by the mathematical model error from recovering methods such as dynamic method, short-arc integrated method, et al. To solve this problem, space-wise least square method is present. The effects of each items which affected the performance of satellite gravimetry are evaluated by this method. The results indicate that the highest degree of the earth gravity model recovered is 240 for the satellite with 500 km orbital height. Then if the error of payload is 1×10-10 m·s-2·Hz-1/2, the degree of model recovered only approach to 136 with the accumulated gravity anomaly error 2.7 mGal and the accumulated geoid height error 14 cm. In order to achieve the best surveying performance, the orbital inclination should be greater than 89°. While, the max degree of the earth gravity model recovered should be greater than 240 so as to reduce the effect of high frequency gravity signal on low degree coefficients recovered. All these conclusions benefit to satellite designing and data processing. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of lactobacillus acidophilus on the expression of nitric oxide (NO) and its oxidative mediators, and to explore the anti-atherosclerosis mechanism of lactobacillus acidophilus. Methods Twentyfour male SPF rats were randomly divided into normal diet group, high-fat diet group and lactobacillus acidophilus group, with 8 rats in each group. The rats in the normal diet group were fed with normal diet, and the high-fat diet group was fed with high-fat diet + intraperitoneal injection of vitamin D3 + immune injury + FeSO4 to establish an atherosclerosis model. The rats in the lactobacillus acidophilus group were intragastrically administered with 0.5 mL of lactobacillus acidophilus per day (1×109 CFU/mL) on the basis of the high-fat diet. Rats were weighed at the 4th, 8th and 12th weekends. After 12 weeks of feeding, the serum was taken from abdominal aorta to detect the contents of oxidized low density lipoprotein (oxLDL), NO, arginine, arginase, and peroxynitrite (ONOO-). The aorta was isolated to observe the morphological change by HE staining. The expressions of eNOS and iNOS mRNA were detected by Real-time PCR, and the expressions of NF-κB p65 subunits were detected by Western blot assay. Results (1) There was no significant difference in body weight between the high-fat diet group and the lactobacillus acidophilus group during the whole experiment (P＞0.05), but both were significantly increased compared with those of the normal diet group (P < 0.01). (2) HE staining showed that the aorta formed a wide range of atherosclerotic lesions in the high-fat diet rats, and the aortic morphology was significantly improved in the lactobacillus acidophilus group. Only endothelial cell proliferation was found, and no smooth muscle cell necrosis was observed in this group. (3) Compared with normal diet group, the serum expressions of oxLDL, ONOO- , arginase, aortic iNOS mRNA and nuclear NF-κB p65 were increased in high-fat diet group (P＜0.01), and the serum arginine content and aortic eNOS mRNA expression levels were decreased (P＜0.01). While lactobacillus acidophilus can just reverse the above changes (P＜0.01). Conclusion Lactobacillus acidophilus may exert anti-atherosclerotic effects by regulating the expression of NOS, increasing NO bioavailability, and protecting endothelial function. [ABSTRACT FROM AUTHOR]

When the sampling rate of base station is lower than that of the rover station, it's impossible to obtain the coordinates of the rover station at all epochs with a conventional differential GNSS post-processing method. To solve this problem, a method based on PPP model is proposed to construct the virtual observation data of the non-sampling points of base station. The method separates the receiver clock error and tropospheric zenith wet delay from the observation error, and estimates them simultaneously with ionosphere ambiguity, after which the distance between the satellite and the station is obtained by base station's real coordinate. On this basis, the method calculates the residual errors of two adjacent epochs, by which the residual errors of non-sampling epochs are fitted. Eventually, the virtual observation data are generated by the non-sampling epochs' residual errors, the distance between the satellite and the station and the estimated errors. Error characteristic of the virtual observation data is maintained, especially the common error between the base station and the rover station; This method only densifies the data of the base station, which will not affect the rover station. The experiment results show that when base station works with a sampling interval within 30 s, the virtual observation data generated by this method are accordant with the real data. In 30s, 15s and 5s sampling intervals, the standard errors of virtual observations of pseudo-range are about 0.2, 0.1 and 0.05 meters, and virtual observations of carrier phase are about 1.2, 0.7 and 0.2 cycles, respectively; In the case of 30 s sampling interval, the positioning result obtained by this method can still meet the cm level accuracy requirements. [ABSTRACT FROM AUTHOR]

In order to study the effect of different application modes of phosphorus-solubilizing bacterial fertilizer(PSB fertilizer)on seedling phosphorus nutrition of Pinus massoniana, a pot inoculation experiment with local and evenly application of PSB fertilizer was set up. We studied the responses of P uptake and root growth of different P. massoniana families under different PSB fertilizer treatments through using WinRHIZO Pro STD1600+ root image analysis software and Molybdenum antimony colorimetric method. The results were as follows:(1)Inoculating PSB fertilizer had a significant effect on growth of P. massoniana seedlings. The main growth indexes, such as seedling height, ground diameter, root dry matter weight, root/shoot and whole plant dry matter weight, significantly increased under local treatment.(2)Local treatment significantly increased the root length, root surface area, root volume and root tip number of seedlings. The root length of 0

Asterias rollestoni is the starfish belonging to the phylum Echinodermata, class Asteroidea. Asterias rollestoni is widely distributed in Chinese waters. The resource of Asterias rollestoni is abundant, and the amount is up to hundreds of thousands of tons every year. Moreover, Asterias rollestoni is rich source of valuable bioactive components, such as lipids, proteins, asterosaponin and polysaccharides. Therefore, Asterias rollestoni has high nutritional values and development potentials as raw materials for marine drugs and functional foods. Extensive investigations of Asterias rollestoni on chemistry and pharmacology have been published in ample literatures at present, but no literature has been reported on Asterias rollestoni gonad lipids, especially on lipid extraction and component analysis. In order to optimize the lipid extraction technology and analyze the lipid and fatty acid compositions of Asterias rollestoni gonads, the extraction process of Asterias rollestoni gonad lipids was performed by microwave-assisted extraction, and the lipid and fatty acid compositions were also studied by nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS) respectively in this paper. Taking extraction rate as an index, the effects of extraction solvent, liquid-solid ratio, extraction time and extraction temperature were studied through the single-factor experiment and the orthogonal experimental design. The experimental results indicated that the optimal extraction process of Asterias rollestoni gonad lipids was as follows: ethyl acetate as solvent, liquid-solid ratio of 7 mL/g, extracting time of 10 min, and extracting temperature of 60 ℃. On the optimized conditions, the extraction yield was up to 33.82%, showing that microwave-assisted extraction method had the advantages of high efficiency and low energy consumption, and had a great application prospect for lipid extraction of Asterias rollestoni gonads. The predominant components of Asterias rollestoni gonad lipids were triglycerides and phospholipids, while the contents of cholesterol and free fatty acids were relatively low. Meanwhile, C14:0, C16:0, C18:1n-7, C20:1n-11, C20:5n-3 (eicosapentaenoic acid, EPA) and C22:6n-3 (docosahexaenoic acid, DHA) were the main fatty acids, and the content of C20:5n-3 and C22:6n-3 accounted for 21.56% of total fatty acids. Moreover, the contents of n-3 and n-6 polyunsaturated fatty acid (PUFA) were respectively 23.62% and 2.71%, and the ratio of n-3 to n-6 polyunsaturated fatty acids was up to 8.72, which was significantly higher than the daily dietary ratio of n-3 to n-6 polyunsaturated fatty acids recommended by Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO). Polyunsaturated fatty acids, especially C20:5n-3 and C22:6n-3 had positive effects on promoting the development of the nervous system and curative effects on preventing cardiovascular disease and anti-inflammatory. Additionally, the atherogenic index (AI) and thrombogenic index (TI) of Asterias rollestoni gonad lipids were 0.81 and 0.29, respectively. In conclusion, Asterias rollestoni gonad lipids have high nutritional values and great exploitation prospects, and can prevent effectively atherosclerosis and thrombosis, and also can be the important dietary sources of C20:5n-3 and C22:6n-3. The experimental results provide the theoretical basis for microwave-extraction, component analysis and comprehensive utilization of Asterias rollestoni gonad lipids. [ABSTRACT FROM AUTHOR]

目的分析河北地区汉族人群载脂蛋白E(ApoE)基因多态性与缺血性脑卒中发病的关系。方法选择 河北地区 128 例缺血性脑卒中患者(观察组)和125例健康查体者(对照组),采集两组空腹静脉血,采用聚合酶链 反应—荧光探针法进行 ApoE 基因型检测,包括e2/e2.e2/e².e2/e4:e3/e3ze3/et,et/e4 共6种表型。比较两组 e2 等位基因携带者(e2/e2+e2/e3)､e3等位基因携带者(e3/e3 + e2/e4).e4 等位基因携带者(e3/etted/et)所 占比例,采用 Logistics 回归分析探讨 ApoE 4 等位基因对缺血性脑卒中发病的影响。结果观察组 e2 等位基因携 带者17例(13.3%),3等位基因携带者87例(68.0%),4等位基因携带者24例(18.8%);对照组分别为 21 例 (16.8%)、92例(73.6%),12例(9.6%);观察组e4 等位基因携带者所占比例高于对照组(P均<005)。单因素 Logistic 回归分析显示,ApoE e4 等位基因､高血压､颈动脉斑块是缺血性脑卒中的危险因素,校正单因素回归分析 中P<0.15的因素后,多因素回归分析结果未显示 4 等位基因是缺血性脑卒中发生的危险因素。结论河北地 区汉族人群 ApoE 4 等位基因多态性与缺血性脑卒中的发病无明显相关,并非其发病危险因素。 [ABSTRACT FROM AUTHOR]

目的 探讨拇指再造时腹部皮瓣二次移植于拇趾甲皮瓣供区的可行性。方法 选择1例右手拇、示、中指腹部带蒂皮瓣修复术后1年,要求行手指再造术患者,在行拇指再造时,切取拇趾甲皮瓣再造拇指,并将原拇指腹部皮瓣带血管游离,二次移植于拇趾甲皮瓣供区。观察再造拇指与足部供区皮瓣成活及恢复情况。结果 术后未出现血管危象等并发症,再造拇指与足部供区皮瓣全部成活。随访15个月,再造拇指与足部供区皮瓣外形良好,再造拇指感觉正常,足部供区无皮肤磨损及破溃。结论 拇指再造时腹部皮瓣二次移植于拇趾甲皮瓣供区,手术损伤小,术后恢复良好。 [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between Bilirubin blood lipid Comprehensive index and apolipoprotein B and the severity of coronary lesions of female patients with coronary artery disease(CAD). Methods: A total of 246 cases of female patients with coronary angiography were divided into 2 sets of groups.(1)According to the results of coronary angiography, the female patients were divided into the CAD group(n=141) and normal control group(n=105);(2)By Gensini scoring system, the female patients were divided into 4 quartile groups: 1 st quartile group(n=35), 2 nd quartile group(n=32), 3 rd quartile group(n=39) and 4 th quartile group(n=35). The blood level of total bilirubin(TBIL), direct bilirubin(DBIL), indirect bilirubin(IBIL), total cholesterol(TC), triglyceride(TG),low density lipoprotein cholesterol(LDL-C), high density lipoprotein cholesterol(HDL-C), apolipoprotein A/B(ApoA/B) level were measured. Bilirubin blood lipid Comprehensive index [TC/(HDL-C+TBIL), LDL-C/(HDL-C+TBIL)] were calculated. Results:(1) The levels of TC, TG, LDL-C and ApoB in CAD group were higher than those of the normal control group; the HDL-C, ApoA, TBIL, DBIL and IBIL were lower than those of the normal control group(P0.05); Compared with the normal group, the ratios of TC/(HDL-C+TBIL)and LDL-C/(HDL-C+TBIL) were increased(P0.05).(2)By Gensini scoring system, the level of TC, LDL-C, ApoB, TBIL, DBIL, IBIL,ratios of TC/(HDL-C+TBIL) and LDL-C/(HDL-C+TBIL) were different among 4 groups(P<0.05).(3)Correlation analysis showed that TC/(HDL-C+TBIL), LDL-C/(HDL-C+TBIL) and ApoB were positively related to Gensini scoring system(r=0.538, P<0.05; r=0.670, P<0.05 and r=0.462, P<0.05). But TBIL, DBIL, IBIL were negatively related to Gensini scoring system(r=-0.485, P0.05; r=-0.564, P0.05 and r=-0.359, P0.05). Conclusions:(1)Bilirubin blood lipid Comprehensive index and apolipoprotein B were significantly higher than the control group, while TBIL, DBIL, IBIL decreased.(2)Bilirubin blood lipid Comprehensive index and apolipoprotein B were positively related to the severity of coronary artery lesions of female CAD patients. [ABSTRACT FROM AUTHOR]

Radial-cephalic arteriovenous fistula(RCAVF) is considered the first choice for hemodialysis vascular access because of its high patency rate and less complications. But up to 50% of the fistula can not mature. This is mainly due to persistent low blood flow or difficulty in cannulation can not lead to adequate hemodialysis. Inflow or outflow stenosis, anastomotic stenosis, exceedingly deep location of the vein, flow diversion into accessory veins are the common causes of impaired maturation. In addition, thrombosis is a common of stenosis. Preoperative assessment by physical examination and ultrasound examination of blood vessels, select the appropriate blood vessels for the fistula is of great significance. Choose the appropriate treatment for the cause of maturation disorders. Postoperative aspirin is widely used to prevent thrombosis and reduce the occurrence of stenosis; Surgery has the advantage of bypassing the damaged area but creating a new stoma; in recent years, endovascular technique because of its characteristics of minimally invasive in most of the time is the first choice. In this paper, the definition, etiology, diagnosis and treatment of fistula maturation disorder are reviewed. [ABSTRACT FROM AUTHOR]

Objective To analyze the surgical complications of deep brain stimulation ( DBS) for movement disorders ( MD) to explore its reason and prevention and treatment measures .Methods 615 patients with MD were received 1008 DBS electrodes.Of 615 patients, 222 received unilateral DBS surgery and 393 received bilateral DBS surgery .Of 615 patients, 566 were medically refractory Parkinson disease, 18 essential tremor, 11 dystonia, 7 cervical distonia, 9 tourette, 2 Meige syndrome and 2 other hyperkinetic movement disorders .The surgical procedure or hardware failure related complications were analyzed retrospectively .Results 615 patients were followed up for 1-3 years.Five severe intraoperative adverse events included intracerebral hemorrhage in 4 (0.7%) and acute edema in 1 ( 0.2%) .Hardware-related complications requiring surgical revision included wound infections in 10 patients (1.6%),Subcutaneous effusion around IPG in 10(1.6%),lead malposition and/or migration in 9(1.5%),component fracture in 10(1.6%), hardware discomfort in 1 patient ( 0 .2%) .Conclusions Many operative skills in DBS are associated with postoperative complications .Improving the experience of surgeon can significantly reduce the incidence of surgical complications. [ABSTRACT FROM AUTHOR]