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61.
Experimental intrahepatic portacaval anastomosis: use of expandable Gianturco stents 总被引:2,自引:0,他引:2
Original Gianturco expandable stents and their modifications were used to create an experimental intrahepatic portacaval anastomosis (EIPCA) in 30 young domestic swine without portal hypertension. The study focused on the design of a suitable stent, the technique of its application, and the evaluation of short-term patency of the EIPCA. A stent with a 2.5-cm-long body and wire skirts on both ends was most suitable for EIPCA creation. Well-positioned stents shunted most of the portal blood in the inferior vena cava circulation and remained patent for 4-6 weeks. Ingrowth of liver parenchyma and abundant proliferation of the intima and connective tissue inside the stent lumen in these rapidly growing animals gradually decreased EIPCA patency, and thrombus formation with diminished blood flow closed them completely. 相似文献
62.
据文献记载和作者的调查,我国产麻黄属(Ephedra)植物共有13种3变种1变型。本文报道我国北方生产的7种麻黄生药形态组织学比较研究结果。7种麻黄是:草麻黄Ephedra sinica Stapf、木贼麻黄E.equisetina Bunge、中麻黄E.intermedia Schrenk ex Mey.、膜果麻黄E.przewalskii Stapf,单子麻黄E.monosperma Gmel.ex Mey.、雌雄麻黄E.fedtschenkoae Pauls和细子麻黄E.reaeliana Florin。文中附有生药性状与组织构造特征比较表及生药组织图 相似文献
63.
Strangulation in child abuse: CT diagnosis 总被引:2,自引:0,他引:2
The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients. 相似文献
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65.
Sternocostoclavicular hyperostosis is a benign ossifying diathesis of unknown etiology characterized by hyperostosis and soft-tissue ossification between the clavicles, anterior portion of the upper ribs, and manubrium, with variable hyperostosis or ankylosis in the spine and sacroiliac joints. Our cumulative experience with 11 cases is reported, with emphasis on radiographic features of the condition. Scintigraphic results in five patients and computed tomographic findings in one patient are presented. A review of the literature and our own material indicates that sternocostoclavicular hyperostosis may be more common than has been previously recognized. 相似文献
66.
国产沉香化学成分的研究——Ⅲ.异白木香醇的结构测定和低沸点成分的分离与鉴定 总被引:4,自引:0,他引:4
自国产沉香(Aquilaria sinensis)[瑞香科(Thymeleaceae)植物]的挥发油中,经硅胶柱层析和离心薄层层析分离得到一新的倍半萜,命名为异白木香醇(isobaimuxinol),根据光谱(IR,1HNMR,13CNMR,2 D-NMR和MS)分析确定其结构式为(Ⅰ)所示,并用X-光衍射晶体解析进一步确定了其立体化学。同时,也从该植物挥发油的低沸点部分分离得到四个已知化合物:苄基丙酮,对甲氧基苄基丙酮,茴香酸和β-沉香呋喃。这些化合物均为首次从该植物中得到。 相似文献
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69.
High-resolution MR imaging with local coils 总被引:4,自引:0,他引:4
We propose the following rules to govern the choice of local coils by the practicing radiologist: 1. Smaller coils permit smaller FOVs and better resolution. The coil should be as small as possible. 2. Match the ROS of the coil to the FOV, which will be determined by the anatomic region of interest. 3. For the case of a choice between surface coils or between a surface and a whole- or partial-volume coil, the anatomic region should lie on the high side of the crossover point. For the case of a choice among whole-volume coils, the smallest coil that surrounds the region of interest should be chosen. 4. Considerations in regard to the anatomic shape or the need to vary the position of the structure may alter the choice of coil from that obtained by S/N considerations alone. 相似文献
70.
国产沉香化学成分的研究——Ⅲ.异白木香醇的结构测定和低沸点成分的分离与鉴定 总被引:3,自引:0,他引:3
自国产沉香(Aquilaria sinensis)[瑞香科(Thymeleaceae)植物]的挥发油中,经硅胶柱层析和离心薄层层析分离得到一新的倍半萜,命名为异白木香醇(isobaimuxinol),根据光谱(IR,~1HNMR,~(13)CNMR,2 D-NMR和MS)分析确定其结构式为(Ⅰ)所示,并用X-光衍射晶体解析进一步确定了其立体化学。同时,也从该植物挥发油的低沸点部分分离得到四个已知化合物:苄基丙酮,对甲氧基苄基丙酮,茴香酸和β-沉香呋喃。这些化合物均为首次从该植物中得到。 相似文献