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61.
采用聚丙烯酰胺凝胶垂直平板电泳技术,对湖北和四川两省5种拟钉螺的酯酶同工酶酶谱进行比较研究,并以湖北钉螺作对照,5种拟钉螺酯酶同工酶共分离出8条酶带,酶谱可分成3区,即EST-1、EST-2、EST-3,其基本特征与钉螺显著不同,很容易通过酶谱将拟钉螺与钉螺区分开,同时,5种拟钉螺的酯酶同工酶酶谱之间均存在一定的差异,说明拟钉螺种间酯酶同工酶存在多态,而种间差异程度似与地域隔离的远近有关。结果提示拟钉螺酯酶同工酶的酶谱特征既有助于拟钉螺属的鉴定,又有助于拟钉螺近缘种的区分,从而对拟钉螺的分类有较大的参考价值。  相似文献   
62.
BACKGROUND CONTEXT: Posterior lumbar interbody fusion (PLIF) is a popular method of arthrodesis for surgical treatment of instabilities and degenerative conditions of the spine. With the introduction of threaded titanium cage devices, surgeons began performing PLIF procedures using these cages as stand-alone devices. Complications have been reported, however, including pseudarthrosis with persistent pain. Outcomes after revision surgical treatment for these patients with failed PLIF are not known. PURPOSE: To prospectively evaluate clinical outcomes of revision fusion surgery in patients who previously underwent posterior lumbar interbody fusion with stand-alone metallic cages resulting in pseudarthrosis. STUDY DESIGN/SETTING: Prospective case series. METHODS: Nineteen patients referred to the senior author were evaluated and diagnosed with pseudoarthrosis having previously undergone a PLIF procedure with stand-alone metallic cages. History, physical exam, and imaging studies were performed preoperatively and postoperatively. All underwent revision posterolateral fusion with iliac crest graft and pedicle screw instrumentation. Patient demographics, SF-36, and Oswestry Disability Index (ODI) data were collected prior to surgery and two years postoperatively. RESULTS: Patients undergoing revision fusion surgery were found to have had extensive facetectomies and pseudarthrosis intraoperatively. Outcomes data was collected on eighteen of nineteen patients (95%). Mean clinical follow up was 3.2 years (range 2.5-3.5 years). Seventeen patients (94%) achieved a solid fusion. Improvement was noted in seven of eight SF-36 sub-categories, but was significant only in two (Physical Function and Role Emotional). There was no significant difference in ODI scores. CONCLUSIONS: Pseudarthrosis should be considered in the differential diagnosis if severe symptoms persist in patients who undergo PLIF with stand-alone metallic cages. Successful revision fusion did not always correlate with improved clinical outcomes in these challenging patients undergoing further surgery. Performing PLIF using stand-alone metallic cages, especially after total resection of the facet joints, is not advocated unless supplemental instrumentation is utilized.  相似文献   
63.
目的研究舰船员慢性荨麻疹发病与马拉色菌的关系。方法对126例舰船员慢性荨麻疹患者及45例健康者进行真菌学比较研究。将马拉色菌阳性的82例慢性荨麻疹患者分为A、B两组,A组单用抗组胺药,B组用抗组胺药联合2%酮康唑洗剂治疗。结果舰船员慢性荨麻疹患者皮肤马拉色菌带菌率高于正常对照组(P<0.01),两治疗观察组于治疗结束时,疗效无显著性差异(P>0.05);治疗结束6~8周后,B组疗效高于A组,有显著性差异(P<0.01),且B组真菌学检查马拉色菌转阴率高于A组(P<0.01)。结论舰船员慢性荨麻疹与皮肤马拉色菌有一定相关性,联合抗真菌治疗能提高其远期疗效。  相似文献   
64.
目的:超声探讨室间隔缺损合并动脉导管未闭(VSD PDA)患者的动脉导管未闭(PDA)显示方法.方法:超声测量41例VSD PDA和41例单纯室间隔缺损(VSD)患儿的主动脉峰值流速(Vp),平均流速(Vm),流速时间积分(VTI)和心排指数(CI).除常规在胸骨旁大动脉短轴切面探查以外,彩色多普勒超声心动图在胸骨旁肺动脉分叉切面、胸骨上主动脉弓长轴,向短轴扫查切面及剑突下主动脉短轴切面探查PDA.结果:41例VSD PDA患者检出PDA 29例,占70.73%,漏诊12例,漏诊率29.27%.VSD PDA患者的Vp、Vm、VTI和CI参数明显高于单纯VSD患者,P<0.001.4例在胸骨旁大动脉短轴切面未显示的PDA,其中2例在胸骨旁肺动脉分叉切面发现PDA,1例在胸骨上主动脉弓长轴向短轴扫查切面显示PDA,1例在剑突下主动脉短轴切面显示PDA.结论:VSD患儿主动脉Vp、Vm、VTI和CI参数增高时提示合并PDA存在.探查VSD患儿胸骨旁肺动脉分叉切面、胸骨上主动脉弓长轴向短轴扫查切面及剑突下主动脉短轴切面有助于发现PDA.  相似文献   
65.
During liver transplantation for hepatocellular carcinoma (HCC) patients, HCC could theoretically be introduced into the systemic circulation when salvaged blood is used with an autotransfusion device. Several reports have shown that some types of leukocyte depletion filters (LDFs) could completely reduce the risk for reintroducing some types of tumor cells. In this study, we tested the ability of the LDF (RCEZ1T, Pall Biomedical Co, NY, USA) to reduce the risk for reintroducing HCC cells in vitro by using a very sensitive detection method. We divided the test group into 6 groups: group I was 10 cells, group II was 20 cells, group III was 2 x 10(3) cells, group IV was 2 x 10(5) cells, group V was 2 x 10(6) cells, and group VI was 2 x 10(7) cells. The counted cells in 200 mL saline were passed through the RCEZ1T using the force of gravity. To identify the presence of cells, the pellet was resuspended, and polymerase chain reaction (PCR) was performed. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a housekeeping gene, was used as a primer. In groups I and II, the HCC cells were completely filtered in all experiments. However, in groups III, IV, and V, the HCC cells were not completely filtered in a few of the repeated experiments, with the unfiltered rate of tumor cells being between 8% and 20%. In group VI, the HCC cells were not completely filtered in all the repeated experiments. In conclusion, the RCEZ1T filter markedly reduced the risk for reintroduction of HCC cells. However, at high HCC cell load the filter cannot completely remove all the tumor cells. Further studies are required to assess the impact in clinical settings.  相似文献   
66.
Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F?<SO4 2?<Cl? <ClO4 ?<NO3 <SCN? <Br <I?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F?, SO4 2?, Cl?, ClO4 ? and NO3 ? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm?1 and 2924 cm?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions.  相似文献   
67.
本实验采用随机引物法标记探针DNA.探针DNA加热变性成单链,以单链DNA为模板,六聚脱氧核苷酸为引物,在DNA多聚酶I大片段的作用下进行放射性标记.标记探针的比放射性达10~8cpm/μg DNA以上.放射性底物的掺入率为60%.用该方法标记的人高度重复顺序探针,可以检出微微克水平的阳性分子.与人HeLa S_3细胞DNA转化的小鼠LTK~+细胞DNA打点杂交呈阳性,与未经转化的小鼠LTK~-细胞DNA杂交为阴性,证明小鼠转化细胞中存在HeLa细胞DNA,DNA转化是成功的.  相似文献   
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70.
Fetal thrombosis of the dural sinus is an extremely rare congenital cerebrovascular condition that is potentially fatal. We report a case of dural sinus thrombosis diagnosed by prenatal ultrasonography and fetal magnetic resonance imaging (MRI) in the second trimester. The thrombosis showed partial resolution during pregnancy and resolved spontaneously after birth without neurological complications. This is the first report of spontaneous postnatal resolution, and may provide helpful information on the natural history and prenatal counseling of fetal thrombosis of the dural sinus.  相似文献   
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