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991.
目的:探讨脉络宁对慢性阻塞性肺病(chronic obstructive pulmonary diseases, COPD)患者血浆内皮素(endothelin, ET)含量变化的影响.方法:选择COPD患者45例在脉络宁应用前及一年时分别测定血浆ET含量为观察组;同期未应用脉络宁的COPD患者为对照组,同时测定ET含量.采用放免法(RIA)测定血浆ET含量.结果:观察组由治疗前(80.49±29.67)pg/ml至一年时(64.38±24.5)pg/ml;对照组(78.28±24.38)pg/ml至一年时(77.49±30.63)pg/ml.二组治疗前对比无差异(P>0.05).应用后,一年时对比有显著性差异(P<0.05).结论:脉络宁对COPD患者具有调节血浆ET使其减少的作用. 相似文献
992.
The modulation transfer function for an elliptical tomographic scan is derived. Its imaging characteristics are compared with
those of linear and circular scans
Zusammenfassung Die Modulationsaustauschfunktion einer elliptischen tomographischen Abastung wird abgeleitet. Ihre Abbildungsmerkmale werden mit denen von linearen und runden Abtastungen verglichen.
Sommaire La fonction de transfert de modulation d'un balayage tomographique elliptique est dérivée dans cet article. Ses caratéristiques d'image sont comparées avec celles des balayages circulaires et linéaires.相似文献
993.
Petersen TR Gülland S Bettelli E Kuchroo V Palmer E Bäckström BT 《International immunology》2004,16(7):889-894
A key question yet to be resolved concerns the structure and function relationship of the TCR complex. How does antigen recognition by the TCR-alphabeta chains result in the activation of distinct signal transduction pathways by the CD3-gammadeltaepsilon/zeta complex? To investigate which part of the TCR-beta chain is involved in TCR signaling, we exchanged different domains of the constant regions of the TCR-beta chain with the corresponding TCR-gamma chain domains. We show here that hybridoma cells expressing a chimeric TCR-beta chain (betaIII) containing intracellular and transmembrane TCR-gamma amino acids, together with a wild-type TCR-alpha (alphawt) chain, were 10 times more sensitive to antigenic stimulation compared to cells expressing TCR-alphawt/betawt chains. This super-signaling phenotype of the betaIII chain was observed in two different TCRs. One specific for an alloantigen (I-A(bm12)) and one for an autoantigen (I-A(b)/MOG(35-55)). We found that this chimeric alphawt/betaIII TCR had normal association with CD3-gammadeltaepsilon and zeta chains. To investigate the effect of the chimeric betaIII chain in transgenic T cells, we made MOG(35-55)-specific TCR transgenic mice expressing either the alphawt/betawt or chimeric alphawt/betaIII TCR. Similar to what was observed in hybridoma cells, transgenic alphawt/betaIII T cells showed a super-signaling phenotype upon antigenic stimulation. Further studies may help us understand the effect of increased TCR signaling on autoimmunity and may lead to the identification of signaling molecules that can be targeted to stop the progression of autoimmune disorders such as multiple sclerosis. 相似文献
994.
J. J. Visser J. E. Hoogkamer M. F. Bobbert P. A. Huijing 《European journal of applied physiology》1990,61(5-6):453-460
Summary Lengths of muscle tendon complexes of the quadriceps femoris muscle and some of its heads, biceps femoris and gastrocnemius muscles, were measured for six limbs of human cadavers as a function of knee and hip-joint angles. Length-angle curves were fitted using second degree polynomials. Using these polynomials the relationships between knee and hip-joint angles and moment arms were calculated. The effect of changing the hip angle on the biceps femoris muscle length is much larger than that of changing the knee angle. For the rectus femoris muscle the reverse was found. The moment arm of the biceps femoris muscle was found to remain constant throughout the whole range of knee flexion as was the case for the medial part of the vastus medialis muscle. Changes in the length of the lateral part of the vastus medialis muscle as well as the medial part of the vastus lateralis muscle are very similar to those of vastus intermedius muscle to which they are adjacent, while those changes in the length of the medial part of the vastus medialis muscle and the lateral part of the vastus lateralis muscle, which are similar to each other, differ substantially from those of the vastus intermedius muscle. Application of the results to jumping showed that bi-articular rectus femoris and biceps femoris muscles, which are antagonists, both contract eccentrically early in the push off phase and concentrically in last part of this phase. 相似文献
995.
本文对60名女性海洛因依赖者与54名健康女性的月经、生育等女性生理机能和性心理及性行为进行调查分析。发现女性海洛因依赖者月经异常率为95.0%,显著高于对照组6.8%(P<0.001);海洛因对性欲和性行为影响明显,吸注海洛因成瘾后,35.0%性欲减退,58.3%性欲消失;性行为方式:吸毒前96.7%以性交为主,吸毒成瘾后仅15.0%以性交为主(P<0.001),85%以非性交接触为主;海洛因成瘾后性能力明显障碍,性交次数由吸毒前平均4.9±1.6次/周减少至平均0.4±0.2次/周(P<0.01)。结果表明:海洛因对女性生理机能和心理卫生具有明显损害作用。 相似文献
996.
目的 比较分析单纯急性戊型肝炎与重叠感染患者的肝功能指标和临床特点.方法 以40例单纯急性戊型肝炎为对照,回顾性分析了122例重叠感染戊型肝炎患者的肝功能指标、临床资料.结果 单纯戊肝组、甲戊重叠感染组、乙戊重叠感染组,三组之间ALT、AST、TBIL、DBIL差异均无统计学意义(P0.05),急性戊肝组与乙戊重叠感染组,甲戊重叠感染组与乙戊重叠感染组的白蛋白、球蛋白有统计学差异(P<0.01);甲戊重叠感染、乙戊重叠感染与单纯戊肝相比较临床合并症多、并发症重.结论 戊型肝炎重叠感染,特别是乙戊重叠感染患者,要加强临床监测,提高早期预防并发症的意识,以降低病死率. 相似文献
997.
目的探讨阿尔茨海默氏病(AD)和帕金森氏病(PD)对老年人认知功能及日常生活能力的影响。方法对2000~2003年就诊于我院的53例AD、68例PD和60例正常人应用简易智力量表(MMSE)和日常生活能力量表(ADL)进行分析。结果AD组与对照组相比MMSE总分及各因子分、ADL总分及各单项分均有显著性差异(P<0.01):PD组与对照组相比除MMSE的记忆力和语言因子分以及ADL第13项目(打电话)外,其余均有显著性差异(P<0.05):AD组与PD组相比除ADL第7项(穿衣)外均有显著性差异(P<0.05)。结论AD和PD对老年人的认知功能和日常生活能力均有显著的影响,两者相比,AD对老年人的影响更严重、更广泛。 相似文献
998.
Dynamic graciloplasty has recently been developed for reconstruction of anal function in patients who are fecally incontinent in preference to permanent abdominal colostomy. Since the muscular portion of gracilis is wrapped around the neoanus, the length of the gracilis arc influences the functional outcome of graciloplasty. Although dissection of the main pedicle (i.e. the main artery and vein) can facilitate gracilis to have enough muscle arc, it has been unclear whether there are any vessels proximal to the main pedicle or through the origin of the muscle which could support blood flow into the whole of gracilis. In this study, the vascular anatomy of gracilis in both legs of 26 Japanese cadavers was examined. All muscles had a main pedicle, mean maximum diameter 1.08 mm, entering at the proximal one-third of the muscle. However, only 18 muscles (34.6%) had an accessory artery in the proximal portion in addition to the main pedicle. Some arteries always exist at the origin of the muscle, having a mean maximum diameter of 0.34 mm, suggesting that they might be able to support the whole gracilis without supply from the main pedicle. 相似文献
999.
目的:研究肝硬化门脉高压症(PHT)大鼠脾次全切除术后CD4、CD8与脾功能的变化。 方法: 皮下注射60%四氯化碳复制大鼠肝硬化模型。共分5组:正常大鼠组、肝硬化(PHT)组、正常大鼠脾切除组、PHT全脾切除组、PHT脾次全切除组,每组10只。手术后第4周检测各组血常规、肝功能、tuftsin、CD4、CD8等指标。 结果:PHT高压症大鼠脾切除术后tuftsin水平[(171±21)ng/L vs (433±44) ng/L,P<0.01]、CD4/CD8(2.01±0.22 vs 1.12±0.12, P<0.01)均显著低于PHT组;PHT大鼠脾次全切除组tuftsin[(434±42)ng/L vs (171±21)ng/L, P<0.01]、CD4/CD8 (1.97±0.18 vs 1.12±0.12, P<0.01)显著高于PHT大鼠脾切除组。肝功能两者无显著差异(P>0.05)。 结论: PHT脾次全切组大鼠术后免疫和脾功能比PHT脾全切组大鼠明显改善,肝功能两者无显著变化。 相似文献
1000.
Reichart B. Schad N. Nickel O. Kemkes B. M. Kreuzer E. Harrington O. B. 《Journal of molecular medicine (Berlin, Germany)》1982,60(4):181-191
Summary Twenty consecutive patients (mean age 51.6 years) with persistent severe angina pectoris underwent aorto-coronary bypass surgery receiving an overall of 60 anastomosis. On an average, 9.4±1.5 months p.o. first pass radionuclide ventriculograms (18 to 24 mCi 99 m Technetium-Pertechnetate i.v.) were performed at rest and after excerise. Besides measurement of global ejection fraction (GEF), regional ejection fraction (REF) was assessed employing for the first time a new technique: each RAO-view of p.o. radionuclide left ventriculogram was subdivided into three regions according to supply of the three main coronary arteries and their branches as visualized on pre-operative coronary angiogram.GEF improved after maximum exercise in 13 cases by 8.1% points (from 50.4 to 58.5%), remained unchanged three times and decreased four times by 7.1 points (from 51.6 to 44.5%; all changesp<0.05).In completely revascularized regions (n=35) REF improved 24 times by 9.7 points (from 51.1 to 60.8%), did not differ from rest REF six times and decreased in three case by 7.3 points (from 48.6 to 41.3%; all changesp<0.05). Completely revascularized regions responded to exercise like normally perfused areas (increase 7.8 points (from 50.6 to 58.4%;n=7;p<0.05).REF deteriorated in incompletely revascularized regions (n=9) six times by 12.8 points (from 58.0 to 45.2%), remained unchanged twice and improved once by 4.5 points. Total group's REF decreased by 7.3 points (from 56.8 to 49.5%;p<0.05). Exercise REF of incompletely revascularized regions was highly significant inferior to that of completely revascularized regions (49.5 to 58.4%;p<0.01).GEF is a weighted balance of the three regional ejection fractions. The most important parameter is REF of LAD territory. 相似文献