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71.
Spatially averaged soil erosion data provide little information on the process of rill erosion. The dynamically varied data on the temporal and spatial distributions in the rill erosion process are needed to better understand the erosion process and reveal its innate characteristics. The objectives of this study were to examine the feasibility and effectiveness of rare earth element (REE) tracers and the neutron activation analysis (NAA) method on the study of the rill erosion process and to reveal quantitatively the relationships and characteristics of temporal and spatial distributions of sediment yield in rill erosion. Four REEs were used to study the changeable process of rill erosion at 4 slope positions. Four water inflow rates were applied to a 0.3 x 5 m soil bed at 3 slopes of 10.5%, 15.8% and 21.2% in scouring experiments. All of the runoff was collected in the experiment. Each sample was air-dried and well mixed. Then 20 g of each sample was sieved through 100-mesh and about a 50 mg sample was weighed for analysis of the four elemental compositions by NAA. Results indicate that the REE tracers and NAA method can be used to not only quantitatively determine soil erosion amounts on different slope segments, but also to reveal the changeable process of rill erosion amount. All of the relative errors of the experimental results were less than 25%, which is considered satisfactory on the study of rill erosion process.  相似文献   
72.
In this study, an animal model of multiple system organ failure (MSOF) in rabbits, engendered by feeding E. coli prior to severe hemorrhagic shock, was used for the purpose of investigating 1) the relationship between lipopolysaccharide (LPS) and MSOF, and 2) the effectiveness of Re-LPS antiserum in preventing MSOF. The results showed that endotoxemia occurred very early, and its degree correlated well with that of organ dysfunction. Re-LPS antiserum administration abated the toxic effects and lowered the incidence of MSOF. These results suggest that sequential analysis of circulating LPS levels may be useful for the early diagnosis of MSOF, and that gut-derived endotoxin might play an important role in the pathogenesis of experimental MSOF.  相似文献   
73.
目的克隆和鉴定日本血吸虫磷酸丙糖异构酶(SjTPI)编码基因,为寻找血吸虫病的候选疫苗联合应用打基础.方法设计合成引物,抽提日本血吸虫成虫总RNA,用RT-PCR法从中扩增出SjTPI基因编码序列,将其克隆入pGEM-T载体,用双酶切、以重组质粒为模板进行PCR扩增和测序进行鉴定.结果 RT-PCR法从成虫总RNA中扩增出大小为759 bp SjTPI基因编码序列,重组质粒pGEM-SjTPI经双酶切、PCR扩增,均可获得一条与RT-PCR产物一致的DNA片段,序列测定结果表明具有一个长度为759 bp的完整开放阅读框,与日本血吸虫(菲律宾株)和曼氏血吸虫磷酸丙糖异构酶核苷酸序列有高度同源性(分别为99%和88%).结论该实验成功地克隆了SjTPI编码基因,为进一步研究提供了条件.  相似文献   
74.
Early multiple organ dysfunction syndrome appears to be facilitated with bacterial translocation in severely burn injury, yet the mechanisms of bacterial translocation remains in dispute. The aim of this study was to investigate the potential role of intestinal bifidobacteria in the pathogenesis of gut-derived bacteria/endotoxin translocation following burns and the effects of bifidobacterial supplement on gut barrier. Methods: Wistar rats were randomly divided into burn group (Burn, n=60),sham burn group (SB, n=10) in experiment Ⅰ , and burn + saline group (BS, n=30), burn + bifidobacteria group (BB, n=30), and sham-burn + saline group (SS, n= 10) in experiment Ⅱ. Animals in BB group were fed bifidobacterial preparation (5 × 109 CFU/ml) after burns, 1.5ml,twice daily. Animals in BS and SS were fed saline. Samples were taken on days 1, 3, and 5 in burn groups, and on day 3 in sham-burn groups. The incidence of bacteria/endotoxin translocation and counts of Bifidobacterium, Fungi and Escherichia coli in gut mucosa were determined with standard methods. The levels of sIgA in mucus of small intestine were measured by RIA. The positive sIgA expression in lamina propria and ileum mucosal injury was evaluated light microscopically by blinded examiners. Results: Our results showed that the incidence of bacterial translocation was increased after burns, which was accompanied by significant decrease in number of bifidobacteria but significant increase in E. coli and fungi in gut mucosa, and elevation of levels of plasma endotoxin and IL-6 (P<0. 001).The incidence of bacterial translocation was markedly reduced after 3- and 5-day supplementation of bifidobacteria compared with control group (P<0.05). The counts of mucosal bifidobacteria were increased by 4- to 40-fold,while E. coli and fungi were decreased by 2- to 30-fold and 10- to 150-fold, respectively, after bifidobacterial supplementation in contrast to control group. The damage of mucosa tended to be less pronounced after 3-day bifidobacteria-supplemented formula compared with control group [grade 2(0-6) vs. grade 4(3-6), P<0.05]. Moreover, the expression and release of sIgA was markedly augmented after 3-day bifidobacteria-supplementation formula and it returned to normal range on day 5. Conclusion: The decrease in counts and proportion of bifidobacteria in mucous membrane flora may play an important role in the development of bacteria/endotoxin translocation following thermal injury. The supplement of exogenous bifidobacteria could per se improve gut barriers, and attenuate bacteria/endotoxin translocation secondary to major burns.  相似文献   
75.
外伤性股动脉栓塞继发肾功能衰竭32例的综合治疗   总被引:1,自引:0,他引:1  
目的 探讨外伤性股动脉栓塞后继发急性肾功能衰竭的临床综合治疗。方法 对32例外伤性股动脉栓塞术后继发急性肾功能衰竭病例均进行急诊手术切开取栓、血管吻合术,术后均予以综合治疗。结果住院时间7天-3个月,平均41d。最终截肢6例,死亡2例,24例修复成功。结论 术前准确判断预后,正确选择手术方式、术中筋膜减张性切开、术后及时清除坏死组织、术后利尿合剂应用和及时必要的血透是影响外伤性股动脉栓塞保肢术后急性肾功能衰竭预后的重要因素。  相似文献   
76.
OBJECTIVE: To study the value of neuronavigation in the transpetroal approach, and to provide anatomic data for the protection of the nerves in the facial nerve canal (FNC) during surgeries. METHODS: Simulated surgery through the transpetroal approach was performed on 16 sides of 8 adult cadaver heads with the assistance by neuronavigation. The anatomy of the facial nerve and the relationship of related structures were observed and the distances from the utmost external edge of the mastoid to different segments of the FNC were measured. RESULTS: Neuronavigation was successful with all the FNC, with the mean error of less than 0.9 mm. The FNC could be divided into 3 segments, the labyrinthine, the tympanic and the mastoid segments, stretching 3.6+/-1.2 mm, 11.2+/-2.5 mm and 16.1+/-3.6 mm respectively and with diameters of 1.2+/-0.3 mm, 1.4+/-0.1 mm and 1.7+/-0.2 mm, respectively. CONCLUSION: Neuronavigation may help protect the FNC during surgical procedures, and a thorough knowledge of the anatomic features of the FNC can be significant for preservation of the facial nerves.  相似文献   
77.
目的探讨软组织血管瘤多排CT血管成像的影像表现方法回顾性分析临床、手术及病理证实20例软组织血管瘤CT平扫、增强和CT血管成像的不同表现结果CT平扫病灶呈软组织密度,5例灶内或灶缘见斑点状或斑块状高密度钙化灶;20例增强后病灶血管成像呈不同表现,12例动脉期瘤体内呈网状血管强化并见明显的瘤体供血动脉,其中单支供血动脉4例,2支以上多支供血动脉8例,供血动脉较对侧明显增粗瘤体内明显迂曲静脉血管6例,而静脉期瘤体表现为网状血管阴影强化8例病变动脉期瘤体不强化或仅轻微强化,且无明显供血动脉参与供血,静脉期瘤体逐渐均匀一致强化结论软组织血管瘤的多排螺旋CT血管成像可清晰显示软组织血管瘤的形态、大小、供血血管  相似文献   
78.
北京农村居民健康状况及卫生服务需求调查   总被引:17,自引:5,他引:12  
目的了解北京农村居民健康状况及卫生服务需求特点。方法从昌平区、顺义区、大兴区、房山区随机抽取25~64岁农民1605人进行统一问卷调查。结果农民高血压自报患病率为22.4%,超重和肥胖率为56.1%;现在吸烟率为34.4%,缺乏运动率为41.6%;家庭主要经济支出为学生上学(35.3%),建房(25.4%)和疾病(21.2%);54.9%家庭医疗费用支出占总收入的10%以上;最关心的健康问题主要是慢性疾病防治(70.2%);最希望获得的健康知识是慢性病预防知识(72%);希望获得健康知识的途径是广播和电视(81%);家庭最希望获得的医疗保健服务是方便看病和获得药物(73.8%)。结论慢性病给农民带来沉重负担,并成为农民关心的主要健康问题。  相似文献   
79.
互叶醉鱼草中的环烯醚萜甙   总被引:1,自引:0,他引:1       下载免费PDF全文
李冲  张承忠  姚华 《中草药》1994,25(5):227-228
从互叶醉鱼草地上部分分出3个环烯醚萜甙粉化合物。经化学和光谱方法测定结构为6-Ocinnamoylcatalpol(I),specioside(Ⅱ)和6-O-cis-p-coumaroylcatalpol(Ⅲ)。其中化合物Ⅲ为首次从自然界发现。  相似文献   
80.
OBJECTIVE: To elucidate the relation of platelet-derived growth factor receptor (PDGFR) and c-Fos protein expressions with human bladder transitional epithelial cell carcinoma (BTCC). METHODS: The expressions of PDGFR and c-Fos were investigated in 11 normal bladder tissue samples, 14 adjacent non-carcinoma tissues and 43 BTCC tissues by means of SP immunohistochemical technique. RESULTS: The c-Fos expression was found in the cell nuclei and cytoplasm, and PDGFR in the nuclear membrane, cytoplasm, and cellular membrane. PDGFR and c-Fos were detected in 81.40% and 48.83% of the BTCC tissues respectively, at the rates both significantly higher than those in normal and adjacent non-carcinoma tissues (P<0.05). Correlation between the expression of c-Fos and the tumor grading was noted (P<0.05). The expressions of PDGFR and c-Fos in tumor blood vessels were significantly higher than those in normal vessels. CONCLUSIONS: The expressions of PDGFR and c-Fos might be involved in the development of BTCC, possibly related to the angiogenesis of the tumors. c-Fos expression can indicated the cell proliferative status of the BTCC.  相似文献   
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