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71.
三峡建坝后血吸虫病传播危险因素研究Ⅲ库区血吸虫病监测方案的研究 总被引:2,自引:0,他引:2
目的了解三峡库区血吸虫病传播危险因素,为三峡库区血吸虫病动态监测提供技术方案。方法在三峡库区进行钉螺生存模拟试验,调查库区流动人口、家畜血吸虫病传染源和钉螺输入库区的潜在危险因素,以及建坝后社会经济发展变化对血吸虫病传播的潜在影响因素,找出库区血吸虫病监测的重点。结果钉螺在三峡库区的适宜环境中能够生长繁殖;血吸虫病传染源主要是往返于血吸虫病流行区的流动人口;从血吸虫病疫区引进花草树木和牲畜,存在将钉螺和动物传染源输入库区的可能;库区社会经济发展可使血吸虫病传入的危险增加,三峡库区已成为血吸虫病的潜在流行区。结论三峡库区血吸虫病监测工作重点应是流动人口、引进的牲畜等血吸虫病传染源和钉螺输入因素的监测。 相似文献
72.
73.
Yaotang Wu Guangping Dai Jerome L Ackerman Mirko I Hrovat Melvin J Glimcher Brian D Snyder Ara Nazarian David A Chesler 《Magnetic resonance in medicine》2007,57(3):554-567
Investigators often study rats by microCT to investigate the pathogenesis and treatment of skeletal disorders in humans. However, microCT measurements provide information only on bone mineral content and not the solid matrix. CT scans are often carried out on cancellous bone, which contains a significant volume of marrow cells, stroma, water, and fat, and thus the apparent bone mineral density (BMD) does not reflect the mineral density within the matrix, where the mineral crystals are localized. Water- and fat-suppressed solid-state proton projection imaging (WASPI) was utilized in this study to image the solid matrix content (collagen, tightly bound water, and other immobile molecules) of rat femur specimens, and meet the challenges of small sample size and demanding submillimeter resolution. A method is introduced to recover the central region of k-space, which is always lost in the receiver dead time when free induction decays (FIDs) are acquired. With this approach, points near the k-space origin are sampled under a small number of radial projections at reduced gradient strength. The typical scan time for the current WASPI experiments was 2 hr. Proton solid-matrix images of rat femurs with 0.4-mm resolution and 12-mm field of view (FOV) were obtained. This method provides a noninvasive means of studying bone matrix in small animals. 相似文献
74.
螺旋CT三维重建脊柱的临床意义和应用前景 总被引:1,自引:0,他引:1
目的:探讨螺旋CT扫描和三维重建在脊柱病变中的临床应用价值。方法:对12例脊柱疾病患者进行螺旋CT扫描和三维重建。结果:腰椎间盘突出症和椎管狭窄症3例,脊柱骨折5例,侧弯畸形2例,肿瘤2例,均得到正确诊治。结论:螺旋CT扫描及三维重建技术可广泛应用于脊柱病变的诊断,能直观显示脊柱病变部位的形态。 相似文献
75.
目的:下颌角截骨是面型轮廓重塑中最常见的一种手术,为了提高手术的精确性,避免不必要的损伤,我们对各种下颌角截骨术操作技巧进行探讨.方法:术前进行面部测量、下颌骨曲面断层X线和头颅正侧位定位X线片投影测量,设计截骨线和去骨量,术式选择口内切口下颌角截骨术、口内切口下颌角外板矢状劈开截骨术、耳后切口下颌角截骨术、耳后和口内联合切口下颌角截骨术;结果:面下部过宽同时下颌角肥大者单纯下颌角截骨效果往往不会很理想,需要同时进行下颌角外侧骨板部分去除,减少面下部的宽度,206例术后两侧对称,效果良好;1例面瘫;2例下颌骨骨折,术中做内固定;3例下颌骨体部成角,3个月后第二手术将突出部分磨平.结论:术前测量设计下颌角截骨的术式和截骨线是十分必要的,根据下颌角肥大的不同类型选择相适应的截骨术式. 相似文献
76.
成年人智力发育与年龄和教育的关系 总被引:2,自引:0,他引:2
本文对韦氏成人智力量表中国修订本25岁及其以上成年人城乡样本共1976人在校正各年龄组的文化程度以后,比较了年龄和教育因素对成年人智力发展的影响。结果发现:与晶体智力有关的测验成绩并不随年龄增大而下降,某些测验(如知识;领悟等)甚至呈上升趋势;与流体智力有关的测验成绩随年龄的增大而下降;而测量精神运动速度(数字符号测验)的成绩受年龄影响最为明显。看来流体-晶体智力理论能较好地解释成年人的典型智力发 相似文献
77.
Summary In order to study the immune function of patients on maintenance hemodialysis (MHD), we assayed NK cell cytotoxicity against
K562 targets in 40 patients on MHD, and the production of IL-2 and IFN in peripheral blood mononuclear cells (PBMC) after PHA
stimulation, in contrast to those in normal controls. The results showed that NK cell activity and IL-2 and IFN levels were
markedly lower in the patients than in the controls. Afeter a single dialysis, NK cell activity as well as IL-2 and IFN levels
were elevated to different extent. But there was no significant change in patients after long-term dialysis. There was a positive
correlation between the NK cell activity and IL-2 and IFN activity in the controls, but no such correlation was found in the
patients on MHD. There was a positive correlation between the NK cell activity and IL-2 activity in patients after dialysis,
suggesting that immune function were impaired in the patients on MHD, with a decline in the activity of NK cell and IL-2 and
IFN, and a disorder of immune regulation cycle. These abnormal immune impairments in the patients could be partly corrected
by hemodialysis. However, long-term hemodialysis is not much helpful in the improvement of patient’s immune function. 相似文献
78.
79.
K Y Dai J C Montet X M Zhao J Amic R Choux 《Gastroentérologie clinique et biologique》1988,12(4):312-319
Methyl tert-butyl ether which is a powerful cholesterol monohydrate solvent does not completely dissolve mixed cholesterol gallstones when directly infused into the biliary tree. In this work, we compared the effect of various solvents containing different proportions of methyl tert-butyl ether and dimethylsulfoxide in anhydrous and aqueous systems on the in vitro solubilization of human cholesterol stones. The dissolution rates of cholesterol obtained in the presence of methyl tert-butyl ether was markedly decreased when 10 p. 100 water was added. In contrast, the addition of dimethylsulfoxide (30 p. 100) to methyl tert-butyl ether-water system enhanced the stone-solvent contact, improved the cholesterol dissolution rates and left less stone debris. A subsequent dissolution with an alkaline, pH = 8.8, aqueous dimethylsulfoxide-ethylenediaminetetraacetic acid solution strongly reduced the non cholesterol residues. In vivo, nearly complete dissolution of human cholesterol stones implanted in the gallbladder of rabbits was obtained within 8 hours when methyl tert-butyl ether/dimethylsulfoxide (70/30) solvent was infused at a rate of 0.6 ml/h/kg. With methyl tert-butyl ether, only 84 p. 100 of the original stone weight was dissolved. The infusion of these solvents leads to morphological changes in the gallbladder wall with some focal ulcerations. These alterations can be almost completely recovered after two weeks. No histologic evidence of hepatic, duodenal or renal damage was found. We conclude that the mixture methyl tert-butyl ether/dimethylsulfoxide (70/30) constitutes a good solvent for mixed cholesterol stones. Compared with pure methyl tert-butyl ether, the mixed system allows for a more rapid and a more complete dissolution of gallstones. 相似文献
80.
戴显伟 《中国普外基础与临床杂志》1996,(1)
作者对胰十二指肠切除术做了四点技术改进:①经小肠系膜根部后方十二指肠水平段隧道提取空肠至横结肠上区,再做吻合;②经结肠后行十二指肠或胃与空肠端侧吻合术;③放置25~30cm长的胰管支撑内引流管;④经胃窦前壁通过幽门及吻合口放置空肠营养管。文内对上述改进的技术进行了详细的介绍,并阐述了每项技术的优点和意义。 相似文献