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21.
高频超声检测颈动脉内膜-中层厚度及外周血管内皮功能评价动脉粥样硬化 总被引:1,自引:0,他引:1
目的 探讨高频超声检测颈动脉内膜-中层厚度与肱动脉内皮依赖性舒张功能在动脉粥样硬化中的诊断价值.方法 冠状动脉造影的老年患者69例及青年志愿者20例,分别行颈动脉超声检查,同时采用充气加压法测定肱动脉血流介导的内径扩张值,超声测值与冠脉造影结果对照分析.结果 ①颈动脉内膜-中层厚度值随粥样硬化斑块的增多、冠脉狭窄程度的加重而增高;②动脉粥样硬化患者在内膜-中层厚度值增高之前即可出现内皮功能损伤,肱动脉内径扩张值降低早于内膜-中层厚度值增高之前出现,内径扩张值随冠脉狭窄程度加重而下降.结论 高频超声检测颈动脉内膜-中层厚度、内径扩张值诊断早期动脉粥样硬化敏感性高,并且有助于对冠脉狭窄程度作出判断. 相似文献
22.
冠心病患者血清对氧磷酶活性的测定 总被引:2,自引:1,他引:1
目的探讨冠心病患者血清对氧磷酶1活性及其与冠心病之间的关系。方法选择冠状动脉造影确诊的冠心病患者106例和非冠心病组62例,用乙酸苯酯法和比色法分别测定两组血脂、血清对氧磷酶1活性、超氧化物歧化酶及丙二醛含量,并进行对比分析。结果冠心病组血清中对氧磷酶1活性和超氧化物歧化酶水平分别为113±64μkat/L和43.8±8.2 kU/L,均较对照组降低(134±72μkat/L和63.4±5.7 kU/L)(P<0.05);而丙二醛含量较对照组升高(9.4±1.8μmol/L比4.1±0.5μmol/L,P<0.01)。对氧磷酶1活性与高密度脂蛋白和超氧化物歧化酶水平呈正相关,与丙二醛水平呈负相关。冠状动脉狭窄者对氧磷酶1活性较无狭窄者明显减低(P<0.001),2、3支血管病变者较1支血管病变者对氧磷酶1活性降低(P<0.05)。结论冠心病患者血清对氧磷酶1活性降低,低对氧磷酶1活性与冠心病严重程度有关。 相似文献
23.
The patella and tibial condyle position after combined and after closing wedge high tibial osteotomy
Miklós Papp Zoltán Csernátony Sándor Kazai Zoltán Károlyi László Róde 《Knee surgery, sports traumatology, arthroscopy》2007,15(6):769-780
High tibial osteotomy changes the patella and tibial condyle position, which makes the subsequent total knee replacement technically
demanding. From 1 January 1993 to 31 December 2000, combined osteotomy [After the first osteotomy made 2 cm distally to the
joint line, a bone wedge is removed based laterally. Its tip ends at the center of the tibial condyle (half bone wedge). The
distal part of the tibia is placed into the valgus position and the half bone wedge is placed into the gap opened medially.]
was performed on 103 knees and closing wedge osteotomy was performed on 47 consecutive knees. Eighty combined (group A) and
41 closing wedge (group B) osteotomy were studied. All knees were assessed radiologically before surgery, in the 10th postoperative
week, in the 12th postoperative month and at the time of the final follow-up (in group A—66.15 months, in group B—66.61 months).
We examined the change of the femorotibial angle, of the patellar height according to the method of Insall and Salvati, of
the tibial slope angle according to the method of Bonnin, of the tibial condylar offset according to the method of Yoshida
and of the distance between the lateral tibial plateau and the top of the fibular head. In group A and B, the recurrence of
the varus deformity was not noted and valgus alignment did not increase in any case. In group-A, the Insall–Salvati ratio
remained unchanged in 65% of knees. The tibial slope angle decreased in both groups. There was correlation between the change
of the tibial condylar offset and the angle of the correction in both groups. There was correlation between the change of
the distance between the lateral tibial plateau and the top of the fibular head. After combined osteotomy, the transposition
of the tibial condyle and the decrease of the distance between the lateral tibial plateau and the top of the fibular head
was less than after closing wedge osteotomy, although the average angle of correction was more after combined osteotomy (11.835°),
than after closing wedge osteotomy (9.465°). Theoretically, the recurrence of the varus deformity, the increase of the valgus
alignment and (in majority of cases) the shortening of the patellar tendon do not compromise the likelihood of successful
conversion to the subsequent total knee replacement, either after combined or after closing wedge osteotomy. The combined
osteotomy does not lead to considerable transposition of the tibial condyle and to considerable lateral tibial bone loss;
therefore, theoretically, the combined osteotomy does not impair the subsequent total knee replacement. 相似文献
24.
胫骨高位截骨手术并发症23例次分析 总被引:2,自引:1,他引:1
[目的] 探讨胫骨高位截骨手术并发症的发生情况,并提出预防和治疗措施。[方法]2000年1月~2004年10月采用胫骨高位截骨术治疗膝骨关节炎合并内翻畸形患者126人,21人发生手术并发症,男4例,女17例;年龄48~64岁,平均61岁。术前拍摄站立膝关节正位X线片,测量股骨一胫骨角,计算截骨角度,采用外侧闭合胫骨高位截骨术矫正膝内翻畸形。[结果] 术后随访6~12个月,平均7.5个月。共21名患者发生各类并发症23例次.发生率为16.7%。其中发生胫骨骨折4例,腓总神经麻痹3例,出现深静脉血栓形成5例,膝内翻复发病例6例,内固定失败4例(其中2例合并膝内翻复发),感染1例。[结论] 降低胫骨高位截骨手术并发症需要术者熟悉局部解剖和精确的术前设计,提高手术技巧及完善的围手术期护理。 相似文献
25.
26.
急进高海拔大鼠肾素-血管紧张素-醛固酮系统的对比性研究 总被引:2,自引:0,他引:2
目的:探讨急进高海拔地区机体对低压、低氧环境的适应机制;方法:将海拔10m处的平原大鼠快速带至海拔2261m,再带入海拔3800m处,用放射免疫法测定大鼠血浆肾素、血管紧张素Ⅱ和醛固酮的浓度;结果:随海拔递增①大鼠肾素及血管紧张素Ⅱ含量呈上升趋势,醛固酮浓度逐渐下降,统计学处理有显著性差异;②急进高海拔地区,醛固酮对血管紧张素Ⅱ的反应钝化,使醛固酮处于低水平状态;结论:上述结果提示:急进高海拔,机体对水、电解质的调节会发生变化,这些变化有利于急性高原适应。 相似文献
27.
HPCE法测定蛹虫草及其培养物中核苷类化合物的含量 总被引:5,自引:0,他引:5
目的 建立蛹虫草中核苷类化合物的高效毛细管电泳测定法 ,比较天然蛹虫草及其培养物中核苷类化合物的含量。方法 在HV - 30 1高效毛细管电泳仪上进行定量分析 ,采用石英毛细管柱 ,以pH9.0的 4 0mmol·L-1 硼砂溶液作为电极缓冲液 ;分离电压为 1 6KV ;检测波长为 2 5 4nm。结果 天然蛹虫草中核苷类化合物主要集中在子座部分。人工培养蛹虫草子座和菌丝中虫草素的含量分别是天然蛹虫草子座中的 5 .0 4倍和 1 0 .85倍 ;液体培养蛹虫草菌丝中腺嘌呤、腺苷、尿苷、鸟苷含量均高于固体培养蛹虫草子座。结论 天然蛹虫草及其培养物中核苷类化合物的种类和含量具有较大的差异。高效毛细管电泳法可以用于蛹虫草的定量分析 ,具有分离度高、简便、准确 ,样品消耗少等特点 相似文献
28.
Changes in temporal gait characteristics and pressure distribution for bare feet versus various heel heights 总被引:8,自引:0,他引:8
The purpose of this study was to identify changes in temporal gait characteristics and pressure generation across the sole of the foot due to various heel heights in women's dress pumps. Thirty female subjects, aged 18-30 years, volunteered to participate. Subjects were required to have normal gait and to wear comfortably either size 7 or size 9 shoes. Subjects were tested initially in bare feet using electrodynography (Langer Biomechanics Group, 21 East Industry Court, Deer Park, NY 11729-9986) (EDG) at a cadence of ~100 steps/min set by metronome. EDG trials with 4 pairs of shoes were then performed in random order. Shoes were women's dress pumps identical except for heel height. Heel heights were 1.75, 3.12, 5.72 and 8.74 cm. Data were collected over ~ 30 steps and averaged over this period. Data were analyzed using a one-way ANOVA, and changes were only considered significant if the ANOVA identified significant variations bilaterally. Considering temporal gait variables, we concluded that: (1) stance phase was shortened in shoes vs. bare feet but was unaffected by heel height, (2) the percentage of stance spent in weight bearing on the lateral and medial calcaneus decreased above a 3.12 cm heel height, (3) the percentage of stance spent in weight bearing on the first and second metatarsal heads increased in shoes vs. bare feet but was unaffected by heel height, (4) the percentage of stance spent in weight bearing on the fifth metatarsal was less in the 8.74 cm heel than in any other shoe or in bare feet. With regard to pressure variables, we found that: (1) peak pressure under the fifth metatarsal head was inversely related to heel height, (2) pressure under the third metatarsal head peaked earliest in heels greater than 5.72 cm high, and (3) pressure under the medial calcaneus peaked latest in heels greater than 5.72 cm high. 相似文献
29.
他汀类药物早期干预对急性冠脉综合征患者血脂、高敏C反应蛋白和纤维蛋白原的影响 总被引:5,自引:0,他引:5
目的 比较他汀类药物和阿司匹林联合用药与单用阿司匹林对急性冠脉综合征患者血脂、高敏C反应蛋白及纤维蛋白原的影响。方法 所有患者均在急性冠脉综合征发病后72h内开始接受药物治疗,他汀组(40例)应用他汀类药物加阿司匹林治疗8周,对照组(16例)单用阿司匹林治疗,观察两组总胆固醇、低密度脂蛋白胆固醇、高敏C反应蛋白和纤维蛋白原水平的变化。结果 治疗8周后,他汀组各指标显著降低,面对照组仅高敏C反应蛋白水平显著下降。他汀类药物降低高敏C反应蛋白、纤维蛋白原的程度与其降脂作用无关。结论 他汀类药物与阿司匹林联合用药降低高敏C反应蛋白和纤维蛋白原的作用可能优于单用阿司匹林,并与其抗炎作用有关。 相似文献
30.
Jason T. Siegel M.A. Eusebio M. Alvaro PhD. M.P.H. Michael Burgoon PhD. 《The Journal of adolescent health》2003,33(6):458-461
This research is supported in part by Arizona Disease Control and Research Commission (ADCRC), Grant #9904 (M. Burgoon, PI). This study assesses how adolescent nonsmokers, at-risk smokers, and smokers differ in perceptions of smoking harms, benefits, and safety. While small differences exist when comparing attitudes and knowledge concerning short- and long-term benefits of smoking, large differences arise when attitudes and knowledge concerning the short-term benefits and the safety of casual smoking are compared. 相似文献