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991.
Nocturnal arousals are the essential cause of disturbed sleep structure in patients with obstructive sleep apnoea syndrome (OSAS). The aim of this study was to analyse the relationship between sleep stages, respiratory (type-R) and movement (type-M) related EEG arousals. Furthermore, the value of these arousals as a criterion for the efficiency of nCPAP treatment was estimated. We examined 38 male patients aged between 30 and 71 (49.1±20.9 SD) y. All patients suffered from OSAS. The mean respiratory disturbance index (RDI) was 47.3±27.8 per h. Polysomnographic monitoring was carried out on 4 subsequent nights: baseline night, 2 nights of nCPAP titration and nCPAP control night. Sleep was visually scored and EEG arousals were classified into type R and M, depending on whether changes of respiration or movement caused the arousal. The RDI, the R index (type-R/h), the M index (type-M/h) and the R and M indices in different sleep stages were calculated. During the baseline night a deficit of slow wave sleep (SWS) and REM sleep was found. Furthermore there were more type-R than type-M arousals registered (17.4 h?1[3.6–43.6] vs. 5.9 h?1[1.6–11.8]) ( P <0.01). They occurred during stages NREM 1, NREM 2 and REM ( P <0.01). An SWS sleep rebound and a reduction of the SWS and REM latencies were already found during the first CPAP night. The R index was reduced during the first CPAP night in all sleep stages ( P <0.01) and remained approximately the same in the following 2 nights (3. CPAP night: 1.1 h?1[0.3–5.0]). Type M arousals occurred more in stages 1 and 2 ( P <0.01), and remained unchanged under nCPAP. We concluded that differentiation of nocturnal arousals may provide more detailed information regarding the influence of breathing disturbances on sleep. Respiratory related, not movement related, arousals may be a useful additional tool in judging the efficiency of OSAS.  相似文献   
992.
993.
雷公藤叶中二萜化合物的研究   总被引:10,自引:0,他引:10  
从雷公藤(Tripterygium wilfordii)叶中分离出九个二萜化合物,经物理常数测定、化学反应、以及波谱数据分析,分别鉴定为雷公藤内酯酮(triptonide,1)、雷公藤内酯醇(triptolide,2)、雷公藤内酯二醇(tripdiolide,3);雷醇内酯(triptolidenol,4)、16-羟基雷公藤内酯醇(16-hydroxytriptolide,5)、雷公藤氯内酯醇(tripehlorolide,6)、雷藤内酯三醇(triptriolide,7),以及新化合物雷公藤内酯二醇酮(tripdiotolnide,8)和13,14-环氧9,11,12-三羟雷公藤内酯(13,14-epoxide 9,11,12-trihydroxytriptolide,9)。新化合物的生物活性正在研究。  相似文献   
994.
995.
Fifty-three patients receiving long-term platelet transfusions were regularly screened for platelet-associated antibodies by a platelet suspension immunofluorescence test (PSIFT) and a lymphocytotoxicity test (LCT). Subsequently, 24 patients became alloimmunized; all of their antibodies were of HLA specificity. Eighty-two single-donor platelet transfusions were given, and the clinical responses were considered satisfactory if the 18-hour corrected count increment was 7.5 x 10(3) per microL or higher. In the meantime, 82 pairs of patient sera and donor lymphocytes were crossmatched. Among 63 crossmatched transfusions, 53 (84%) resulted in a satisfactory increment, with a mean (+/- SEM) of 17.71 +/- 1.96 (x 10(3)/microL), and 10 did not result in a satisfactory increment. The increments after 19 unmatched transfusions and 25 random-donor (uncrossmatched) transfusions were 0.7 +/- 0.3 and 2.39 +/- 0.66, respectively. The difference was not significant (p greater than 0.05). The agreement between the LCT results and clinical response was 88 percent. Retrospectively, the corrected count increments showed no significant differences (p greater than 0.05) among three groups of HLA grading: the increments for A/BU/BX, C/D, and random HLA matches were 22.97 +/- 4.07, 15.1 +/- 1.97, and 14.85 +/- 2.04, respectively. These results suggest that platelet crossmatching by LCT is an effective method for use in alloimmunized patients, especially Chinese patients.  相似文献   
996.
反相高效液相色谱法测定环胞霉素全血浓度及药代动力学   总被引:5,自引:0,他引:5  
环胞霉素(cyclosporine)是由11个氨基酸组成的一种环状多肽,具有选择性的免疫抑制作用,目前国内外已广泛用于各种器官移植及骨髓移植。环胞霉素口服吸收不完全,消除半衰期长,体内个体差异大,文献报道其相对生物利用度可从7.6~47.6%。环胞霉素血浓度过高将引起肝肾毒性及其他毒性反应,血浓度太低则影响疗效,病人将会出现排斥反  相似文献   
997.
998.
Balanced translocations affecting the 11q23 region are among the most frequent chromosomal abnormalities in childhood acute lymphoblastic leukemia (ALL), comprising 5% to 6%. These cases consistently have a rearranged MLL gene and are associated with high-risk presenting features, hyperleukocytosis and younger age, and a poor treatment outcome. To assess the clinical and biologic significance of 11q23- associated structural chromosomal abnormalities other than translocations, we studied 17 cases of childhood ALL [14 with del(11)(q23) and 3 with inv(11)(p12q23)] that were identified among 785 cases with successful chromosome analysis. In contrast to reported cases with 11q23 and MLL gene rearrangement, our series was characterized by relatively low leukocyte counts (median, 15.1 x 10(9)/L), expression of CD10 antigen but not myeloid-associated CD15 and CDw65 antigens, a relatively high frequency of T-cell immunophenotypes, and a generally favorable prognosis. All 13 cases with interpretable molecular analysis lacked MLL gene rearrangements. We suggest that most cases with deletions or inversions affecting the 11q23 region represent clinically and biologically different entities as compared with those defined by 11q23 translocation.  相似文献   
999.
1000.
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