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91.
S Niikawa  S Hara  N Ohe  Y Miwa  A Ohkuma 《Canadian Metallurgical Quarterly》1997,37(12):881-4; discussion 884-5
Serial changes in platelet and white blood cell (WBC) counts and other blood parameters were analyzed in 103 patients with aneurysmal subarachnoid hemorrhage (SAH). The WBC counts during days 3-5, 6-8, 9-11, and 12-14 after the onset of SAH were significantly higher in patients with than in patients without symptomatic vasospasm. Platelet counts during days 0-2, 3-5, 6-8, 9-11, 12-14, 15-17, 18-21, and 22-28 after SAH were significantly higher in patients with than in patients without symptomatic vasospasm. Monitoring of platelet and WBC counts may provide an indicator of the occurrence of symptomatic vasospasm.  相似文献   
92.
High-temperature fracture behavior of melt-infiltrated SiC-Mo(AI,Si)2 composites was studied. The composites exhibited moderate strength up to ∼1600°C under a fast loading rate. The softening of the Mo(Al,Si)2 phase determined dominantly the temperature over which the strength decreased. The composite with finer microstructure revealed a higher level of strength over the whole temperature range. At 1580°C, however, the composites revealed distinct strength degradation at a reduced loading rate.  相似文献   
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Brassidic acid was prepared by elaidinization of 95% erucic acid with 4 mole % nitrous acid at 70 C for 30 min, followed by crystallization from 95% ethanol. Yield was 70%, and purity was 96–97% by gas liquid chromatography and thin layer chromatography. The isomerization reaction was monitored by IRtrans absorption for optimal reaction rate and yield. There was no migration of the double bond. The NMR spectrum of thetrans protons was wide and complex with a chemical shift of 5.34 δ. The nitrous acid elaidinization, generally explained as a free radical process, is believed to be induced initially by the nitrogen dioxide anion (nitrite) and followed immediately by complex formation between the excited triplet anion and the olefin. The complex rotates to the opposite geometric configuration driven by a spin-orbital coupling process. N. Market. Nutr. Res. Div., ARS, USDA.  相似文献   
96.
Biosynthetic regulation of phytochelatins, heavy metal-binding peptides   总被引:1,自引:0,他引:1  
Phytochelatins (PCs) are heavy metal-binding peptides that play important roles in the detoxification of toxic heavy metals and the regulation of intracellular concentrations of essential metals in eukaryotes, including higher plants, fungi, and microalgae. Recently, PC synthase genes in higher plants and fission yeast have been identified and characterized, enabling molecular biological studies to unravel the mechanisms underlying PC synthesis. Moreover, recent routine database searches have unexpectedly identified genes that are similar to plant PC synthase genes in the genomes of worms and some prokaryotes. In this review, we introduce these recent advances in our understanding of the molecular mechanisms for PC biosynthesis and functions in order to supply basic information about the unique and attractive peptides applicable to various fields.  相似文献   
97.
Quantitative measurements of epoxyoleic acid and co-occurring fatty acids in maturingVernonia anthelmintica (L.) Willd. seeds were made to elucidate partially the mode of epoxyoleic biosynthesis. Free (+)threo-12,13-dihydroxy-cis-9-octadecenoic acid was the major component at an intermediate maturation stage, and is believed to be dehydrated to free epoxyoleic acid before incorporation into glycerides. Presented before the Division of Biological Chemistry, Am. Chem. Soc. meeting in St. Louis, Mo., 1961. A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.  相似文献   
98.
Allyl esters of erucic, brassidic, behenic, oleo-erucic, and stearo-behenic acids, prepared by refluxing benzene solutions of the acids with excess allyl alcohol in the presence of p-toluenesulfonic acid monohydrate, polymerize smoothly in the presence of 5 wt. % t-butyl perbenzoate at 120°C for 24 hr. Polymerization of the unsaturated acid esters involves a large portion (ca. 84%) of allylic and a small portion (ca. 26%) of ethylenic bonds. The products, saturated and unsaturated, have a degree of polymerization between 6 and 10 and are soluble in typical polymer solvents. Crystallinity, judged by thermal analysis, decreased with increased cis unsaturation. The oligomers melted between ?30°C and 59°C and started decomposing at 200°C.  相似文献   
99.
OBJECTIVE: To compare the influence of incongruent (asymmetric) follicular development on treatment outcome in IVF-ET and GIFT cycles. DESIGN: A retrospective comparative study. SETTING: Tertiary referral center for infertility. PATIENT(S): Five hundred forty-three consecutive assisted reproduction cycles (428 IVF-ET and 115 GIFT) in 422 infertile patients. INTERVENTION(S): Controlled ovarian hyperstimulation (COH) and IVF-ET or GIFT. MAIN OUTCOME MEASURE(S): The incongruity ratio as a parameter of the asymmetry in follicular development and pregnancy rate (PR). RESULT(S): For GIFT cycles, the PRs were 37.8% and 15.7% in cycles with congruent and incongruent follicular development, respectively. However, for IVF-ET cycles, the PR was not affected by incongruent follicular development: 28.2% and 29.0%, respectively. An inverse relationship was observed between the degree of incongruity and the estimated probability of pregnancy in GIFT cycles but not in IVF-ET cycles. Neither the side of the dominant ovary nor the degree of incongruity were consistent in consecutive cycles. CONCLUSION(S): Incongruent follicular development during COH has a significantly negative influence on the outcome of GIFT cycles but not on the outcome of IVF-ET cycles. The reason for this difference is not clear. We recommend considering IVF-ET instead of GIFT if incongruent follicular development occurs.  相似文献   
100.
High-performance rubrene single-crystal field-effect transistors are developed with binary ionic liquid electrolytes used for gating. Inclusion of small amount of inorganic salts in the ionic liquids enhances the degree of dissociation for the organic ions and accelerates formation of the electric-double-layers in response to the gate voltage. High carrier mobility of 2.9 cm2/Vs is achieved in the rubrene single-crystal transistors with the mixture ionic liquid. In addition to the advantage of the low-voltage operation due to concentrated field in ultra-thin electric-double-layers, drastically increased capacitance at above 100 Hz makes the technique of the ionic liquid gating more attractive for fast-switching devices.  相似文献   
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