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81.
Abstract: The plasma ratio of each neutral amino acid (tryptophan (TRP), tyrosine (TYR), valine, isoleucine, leucine (LEU) or phenylalanine) to the sum of the other neutral amino acids was measured in 16 : manic and 14 : depressed patients. In the manics, there was a correlation between the psychomotor activity and the plasma TRP and LEU ratios. In the depressives, the depressed mood, retardation and global severity were correlated with the TRP ratio. The zotepine responders showed an increase in the TRP ratio after treatment. In the mianserin responders, the TYR ratio, which was high before the treatment, decreased to the normal range after the treatment. But, the plasma amino acid ratios remained unchanged in the patients treated with lithium carbonate or amitriptyhe. These results suggest that, in manic-depressive illness, there might be abnormalities in the metabolism of neutral amino acids, mainly of TRP and TYR, and that the plasma TRP and TYR ratios might be important indicators for determining the efflcacy of some drugs.  相似文献   
82.
M. Sekimoto  M. Fukui  & K. Fujita 《Anaesthesia》1997,52(12):1166-1172
We studied seven analytical methods of estimating the plasma volume from the decay curves of indocyanine green. Fifteen volunteers received 1.0 mgkg−1 of the dye by intravenous injection and the plasma concentration was measured continuously using spectrophotometry. Plasma volumes were calculated using three single-regression methods (1-a, 1-b, 1-c) and four biexponential regression methods (2-a, 2-b, 2-c, 2-d). The means (SD) of 1-a, 1-b and 1-c were 39 (5.0), 44 (5.7) and 54 (11.5) mlkg−1, respectively, and these were significantly different from each other (p < 0.05). The values for methods 2-b, 2-c and 2-d were similar to each other: 39 (4.6), 40 (4.1) and 40 (4.0) mlkg−1, respectively. These required more than 3 min circulation or mixing time. When the time allowed for mixing was less than 3 min (method 2-a) the plasma volume was underestimated. We conclude that plasma volume estimation using indocyanine green and spectrophotometry is most accurate when the mixing time is adequate (3–5 min) and the decay curves are analysed using biexponential regression.  相似文献   
83.
Summary. The aim of the present study was to establish a more differentiating indicator of plasma membrane integrity of spermatozoa than the classic version of the hypoosmotic swelling test according to Jeyendraan. Spermatozoa were prepared by density gradient centrifugation (90% Percoll) to select 'fertilization competent' spermatozoa only. After a second washing procedure sufficiently pure sperm cell suspensions were obtained. The volume distributions of these sperm cells were measured with a Coulter Counter at 25 °C after adaptation in 300 mosmolar NaCl solution resp. 150 mosmolar NaCl solution for 5 min. These volume distributions showed significantly different patterns for the isotonic and hypotonic stress situation in the simple salt solution. Moreover, the comparison of the response to hypoosmotic stress showed more than four reproducible characteristic patterns, promising well differentiated results for different sperm populations. The new method for the detection of hypoosmotic swelling effect might be a real and valuable functional parameter.  相似文献   
84.
利用TiCl4+O2体系,在高频等离子体化学气相淀积反应器中合成了纯度高、粒度细的TiO2粒子。考察了工艺条件对TiO2粒子物性的影响;探讨了TiO2粒子晶型控制的方法,金红石型质量分数可通过工艺条件控制;探讨了TiO2粒子晶型控制的方法。金红石型质量分数可通过工艺条件控制,减少TiO2单体浓度可提高金红石型质量分数;也可通过在原料TiCl4中添加AlCl3等晶型转化剂,使可转化为单一金红石型Ti  相似文献   
85.
AnAnalysisofChromosomeonSterilityCausedbyAzoospermiaorOligospermia¥WuMeiheng;TangWingnuo.(ACTAACADEMIAEMEDICINAENANJING,1995(...  相似文献   
86.
Background: The placental transfer of the a2 receptor agonist clonidine, earlier used as an adjuvant in obstetric epidural analgesia, was compared with the transfer of the newer and more %-selective agonist dexmedetomidine.
Methods: Term placentas were obtained immediately after delivery with maternal consent and a 2-hour recycling perfusion of a single placental cotyledon was performed. Disappearance from the maternal circulation, accumulation in placental tissue and appearance in the fetal circulation of clonidine or dexmedetomidine with the reference compound antipyrine were followed in 4 experiments for both drugs.
Results: At 2 hours the percent dexmedetomidine found in the fetal circulation was 12.5 (SD 5.1)%, while 48.1 (SD 20.3)% was found in the perfused placental cotyledon. A higher mean clonidine than dexmedetomidine concentration was achieved in the fetal circulation (1.90 vs. 0.56 nmol/l, P <0.05). At 2 hours the percent clonidine found in the fetal circulation was 22.1 (SD 2.4)% ( P <0.05), while 11.3 (SD 3.3)% ( P <0.05) was re tained in the perfused placental cotyledon. The transfer indexes, describing maternal-to-fetal transfer of dexmedetomidine and clonidine normalized with the transfer of antipyrine, were 0.88 (SD 0.07) and 1.04 (SD 0.08) respectively ( P <0.05).
Conclusions: Dexmedetomidine disappeared faster than clonidine from the maternal circulation, while even less dexmedetomidine was transported into the fetal circulation. This was due to its greater placental tissue retention, the basis for which probably is the higher lipophilicity of dexmedetomidine.  相似文献   
87.
应用硫代乙酰胆碱-联硫代双硝基苯甲酸(ASCh-DTNB)比色测定法,测定了40名健康者及5名贫血者血样的全血胆碱酯酶(bl-ChE)活力值、红细胞胆碱酯酶(e-ChE)活力值及血浆胆碱酯酶(p-ChE)活力值,探讨它们之间的比例关系并用红细胞计数值(RBC)校正酶活力。结果表明:e-ChE与b1-ChE之间关系密切(r=0.948,P<0.001),e-ChE稳定地占bl-ChE的84.97%,在质和量两方面验证了以bl-ChE值表示e-ChE值的可靠性和可信程度,血液胆碱酯酶(b1ChE)活力主要取决于e-ChE活力,RBC值的离散对e-ChE值有极大影响,故用RBC值校正e-ChE活力,这样可缩小人群测定值的变异度,得到较难确的群体均值;消除男女之间测定值的差异,建立更合理和通用的临界参比值,极大地方便了使用,使血液胆碱酯酶(CHE)活力测定法在防治有机磷农药中毒中的应用,更为敏感和特异。  相似文献   
88.
89.
We compared the effectiveness of Ca2+ entering by Na+/Ca2+ exchange with that of Ca2+ entering by channels produced by membrane depolarization with K+ in inducing catecholamine release from bovine adrenal chromaffin cells. The Ca2+ influx through the Na+/Ca2+ exchanger was promoted by reversing the normal inward gradient of Na+ by preincubating the cells with ouabain to increase the intracellular Na+ and then removing Na+ from the external medium. In this way we were able to increase the cytosolic free Ca2+ concentration ([Ca2+]c) by Na+/Ca2+ exchange to 325 ± 14 nM, which was similar to the rise in [Ca2+]c observed upon depolarization with 35 mM K+ of cells not treated with ouabain. After incubating the cells with ouabain, K+ depolarization raised the [Ca2+]c to 398 ± 31 nM, and the recovery of [Ca2+]c to resting levels was significantly slower. Reversal of the Na+ gradient caused an −6-fold increase in the release of noradrenaline or adrenaline, whereas K+ depolarization induced a 12-fold increase in noradrenaline release but only a 9-fold increase in adrenaline release. The ratio of noradrenaline to adrenaline release was 1.24 ± 0.23 upon reversal of the Na+/Ca2+ exchange, whereas it was 1.83 ± 0.19 for K+ depolarization. Reversal of the Na+/Ca2+ exchange appeared to be as efficient as membrane depolarization in inducing adrenaline release, in that the relation of [Ca2+]c to adrenaline release was the same in both cases. In contrast, we found that for the same average [Ca2+]c, the Ca2+ influx through voltage-gated channels was much more efficient than the Ca2+ entering through the Na+/Ca2+ exchanger in inducing noradrenaline release from chromaffin ceils. This greater effectiveness of membrane depolarization in stimulating noradrenaline release suggests that there is a pool of noradrenaline vesicles which is more accessible to Ca2+ entering through voltage-gated Ca2+ channels than to Ca2+ entering through the Na+/Ca2+ exchanger, whereas the adrenaline vesicles do not distinguish between the source of Ca2+.  相似文献   
90.
The mistreatment of elderly is subject to various social constructions. On two geographically distinct Plains Indian Reservations which we call Lone Mountain and Abundant Lands, the abuse or neglect of elderly is construed as a health problem which is a dysfunction of the community as a whole. Both physical abuse and neglect are more common on the Lone Mountain Reservation, occurring in association with other indicators of community disorganization such as unemployment and substance abuse. On the Abundant Lands Reservation physical abuse was categorically denied and what neglect existed appeared to be a function of role strain, geographic dispersal, climate and terrain. We attribute differences in the prevalence of mistreatment of elders to variations in economic opportunities for younger residents. Examining the historical and present contexts of intergenerational relationships on the reservations, we discuss the implications of this study for social exchange theory and policy applications.This research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America Applied  相似文献   
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