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91.
The NADH reductase component of the steroid 9α-hydroxylase fromMycobacterium fortuitum was purified to homogeneity. Recovery of the enzyme from the 50≈60% ammonium sulfate saturated fraction was 49%, with a purification
factor of 100-fold. The NADH reductase has a relative molecular mass of 60 KDa as determined by SDS-PAGE. The absorption maxima
at 410 and 450 nm indicate the presence of iron-sulfur group and flavin. These prosthetic groups seemed to function as redox
groups that transfer electrons from NADH to the following protein. The KM value for NADH as substrate was 68 μM. The NH2-terminal amino acid sequence of the reductase was determined as Met-Asp-Ala-Ile-Thr-Asn-Val-Pro-Leu-Pro-Ala-Asn-Glu-Pro-Val-His-Asp-Tyr-Ala-Thr.
This sequence does not show a homology with the NH2-terminal sequences reported for the reductase component of other monooxygenases, suggesting that the NADH reductase component
of the steroid 9α-hydroxylase system is novel. 相似文献
92.
An immunohistochemical study using the mirror-image technique was performed in order to establish whether amyloid P component is involved in the mechanism of deposition of amyloid fibrils in senile plaques (SPs) in Alzheimer-type dementia (ATD). Ninety percent of /A4 protein-immunoreactive SPs were also stained by the anti-amyloid P component immunchistochemistry, and this applied to all of the diffuse, primitive and classical types of /A4 deposits. These findings may suggest an involvement of amyloid P component in the formation of amyloid fibrils in senile plaques in ATD brains. 相似文献
93.
A new long shelf life formulation of modified Ham's F-10 medium: Biochemical and clinical evaluation 总被引:1,自引:0,他引:1
Paul S. Weathersbee Mary M. Francis Thelma M. Macaso Mark V. Sauer Richard J. Paulson 《Journal of assisted reproduction and genetics》1995,12(3):175-179
Purpose To evaluate biochemically and clinically a new formulation of modified Ham's F-10 medium made without the inclusion of hypoxanthine. The medium was formulated for long-term storage and use by separately preparing a stable liquid (basal) portion and a freeze-dried supplement containing the labile medium components.Results Following 18 months of storage the basal medium was biochemically analyzed for its amino acid (aa's) and vitamin content. Cysteine and tryptophan were decreased to less than 30% of their starting theoretical concentrations (STCs). Asparagine, serine, tyrosine, histidine and lysine were present at 50% to 70% of their STC. The remaining aa's were all within 90% of their STCs except arginine which was at 77%. All of the vitamins were present at 90% or more of their STCs except inositol, riboflavin and'thiamine which were present at 70% of their STCs. IVF with the new formulation resulted in 13 deliveries from 51 aspirations (25%) as compared with 10/39 (26%) in 1991, when standard medium preparation was used. Oocyte donation resulted in 30 deliveries from 84 cycles (36%) with the new formulation as compared with 21/65 (32%) in 1991.Conclusions (1) The new basal with lyophilized supplement formulation produces similar clinical results in the IVF laboratory as medium prepared in the standard fashion, (2) certain amino acids and vitamins are not stable in the liquid basal medium, and (3) the separate formulation of a liquid basal medium with lyophilized supplement is convenient, viable alternative to modified Ham's F-10 medium prepared in the standard manner (i.e., from powder) and may decrease the need for frequent medium preparation.Modified Ham's F-10 Medium, Irvine Scientific, Santa Ana, California.Presented at the 42nd Annual Meeting of the Pacific Coast Fertility Society, Indian Wells, California, April 20–24, 1994. 相似文献
94.
95.
目的 探讨成分输血对恶性血液病患者自体外周血干细胞移植后的支持效果。方法 恶性血液病患者经预处理化疗及干细胞回输后,在骨髓“空虚”期当Hb< 80g/L 时,输注照射的浓缩红细胞;血小板< 20 ×109/L时,输注照射的富血小板血浆,血小板输注量3 .0 ×1011 。结果 输注血小板悬液的患者,血小板计数可提高(6 ~26)×109/L,维持时间为1 ~4 天,无1 例因血小板过低致颅内出血。结论 成份输血是自体干细胞移植后的强有力支持,其中血小板输注的数量最为关键 相似文献
96.
IntroductionInthedonorbloodcolectedbybloodcen-ters,leukocyteshavenotherapeuticfunctiontopatientsbutmayinducemanysideefects.Co... 相似文献
97.
Summary The cortical imaging technique (CIT), a mathematical method for simulating the potential fields on the surface of the brain, was used to analyze the spatio-temporal progression of the AEP P300 component (as well as the preceding and subsequent N2a and N3 components) from thirty normal adult subjects recorded in a standard oddball paradigm. Comparisons were made between the progressions of the endogenous event-related cognitive potentials and the exogenous stimulus-dependent potentials (Nl component). Cortical imaging results suggest that different and multiple generator sites are involved in the production of exogenous and endogenous evoked responses. We particularly note the asymmetric development of the P300 component and the apparent anterior generator sites for the N2a component. This last result is interesting because the N2a precedes the P300 component and supports an earlier frontal contribution. 相似文献
98.
Scopolamine Effects on Visual Information Processing, Attention, and Event-Related Potential Map Latencies 总被引:6,自引:0,他引:6
Daniel Brandeis Hilary Naylor Roy Halliday Enoch Callaway Lovelle Yano 《Psychophysiology》1992,29(3):315-335
We measured performance and event-related brain potential (ERP) map latencies in 12 subjects during four visual discrimination tasks to compare the timing of scopolamine effects on information processing and attention. "Topographic component recognition" found ERP map latencies at times of best fit with a component model map. This "common topography" criterion minimized topographic differences among conditions to facilitate latency interpretations. Scopolamine slowed N1 latency in all tasks, and P3 and reaction time in some tasks. The drug delayed responses to easy targets more than to hard targets. It also induced a disproportionate N1 delay for unilateral high spatial frequency gratings. Both effects reflect a scopolamine-induced impairment when processing targets that usually capture attention. Scopolamine also impaired accuracy for unilateral high spatial frequency gratings, and for gratings presented at probable locations, confirming and extending previous findings. Scopolamine-induced P1 and N1 delays showed that visual processing was affected. Several results were inconsistent with a serial stage model. We suggest that scopolamine both delays selected processes and impairs a processing mode based on automatic capture of attention, inducing more serial processing. 相似文献
99.
目的 :从生物力学角度探讨肱骨外髁骨折的发生机制和固定方法。方法 :通过电测实验法、三维光弹实验法 ,空间有限元分析法 ,研究肱骨外髁在各种体位下的受力情况和复位固定方法 ,三种实验方法互为验证 ,并应用于临床。结果 :66例肱骨外髁翻转骨折病人 ,经治疗优良率达 90 .9%。结论 :肱骨外髁骨折好发于肘关节半屈曲位跌倒 ,和肘关节伸直内翻位跌倒。骨折复位后固定在屈肘 60°~ 90°前臂旋后位最为稳定。本实验结论具有推广应用价值。 相似文献
100.
ZMS对老年大鼠脑内NGF和BDNF的影响 总被引:15,自引:3,他引:15
目的 研究自然衰老大鼠脑内两种神经营养素与学习记忆的关系 ,以及中药活性成分ZMS的作用。方法 用Y 迷宫测试动物的学习记忆功能 ,酶联免疫吸附分析法测定脑组织中BDNF和NGF的含量。结果 老年大鼠的学习和记忆成绩比青年大鼠差 (P <0 0 1) ,脑组织中BDNF的水平降低 ,NGF的变化无显著性。老年鼠喂服ZMS 2mon后 ,学习和记忆能力改善 ,正确次数 /反应总时间比值提高 (P <0 0 1) ,同时BDNF含量也高于老年组 (P <0 0 1)。但是ZMS对脑内NGF含量无影响。结论 ZMS能提高增龄引起的脑BDNF降低 ,从而对神经元起保护作用 ,这可能是ZMS改善老年大鼠学习记忆功能的重要机制之一 相似文献