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51.
(1) The efficacy of the oxime HL?7 and currently used oximes (pralidoxime, obidoxime, HI-6) to reactivate acetylcholinesterase inhibited by various nerve agents (sarin, tabun, cyclosarin, VX) was tested by in vitro methods. (2) Both H oximes (HL?-7, HI-6) were found to be more efficacious reactivators of sarin and VX-inhibited acetylcholinesterase than pralidoxime and obidoxime. On the other hand, their potency to reactivate tabun-inhibited acetylcholinesterase is very low and does not reach the reactivating efficacy of obidoxime. In the case of cyclosarin, the oxime HI-6 was only found to be able to sufficiently reactivate cyclosarin-inhibited acetylcholinesterase in vitro. (3) Thus, the oxime HL?-7 does not seem to be more efficacious reactivator of nerve agent-inhibited acetylcholinesterase than HI-6 according to in vitro evaluation of their reactivation potency and, therefore, it is not more suitable to be introduced for antidotal treatment of nerve agent-exposed people than HI-6.  相似文献   
52.
53.
Studies by comparative genome hybridization have suggested that 5p amplification is related to tumor progression in urinary bladder cancer. In this study seven genes (TAS2R, ADCY2, DNAH5, CTNND2, TRIO, ANKH, and MYO10) located to 5p15.31-5p15.1 were analyzed by fluorescence in situ hybridization using a tissue microarray containing samples from tumors and cell lines with known 5p amplification by comparative genome hybridization. Amplification frequency was highest for TRIO, which maps to 5p15.2 and encodes a protein with a putative role in cell-cycle regulation. To further investigate the role of TRIO amplification in bladder cancer, a tissue microarray containing samples from 2317 bladder tumors was used for fluorescence in situ hybridization analysis. TRIO amplification was strongly associated with invasive tumor phenotype, high tumor grade, and rapid tumor cell proliferation (Ki67 LI) (P < 0.0001 each). Only 7 of 456 pTaG1/G2 tumors (1.5%) but 62 of 485 pT1-4 carcinomas (12.8%) had TRIO amplification. TRIO amplification was not associated with poor prognosis. Using a frozen bladder tumor tissue microarray RNA in situ hybridization confirmed that TRIO is up-regulated in amplified tumors. It is concluded that TRIO up-regulation through amplification has a potential role in bladder cancer progression.  相似文献   
54.
Summary: Bis(hydroxy)telechelic bisphenol A polycarbonate (PC) was prepared via melt polycondensation of bisphenol A (BPA) and diphenyl carbonate (DPC) using lanthanum(III ) acetylacetonate as a catalyst for transesterification. Subsequently, the polycarbonate was converted to a bifunctional macroinitiator for atom transfer radical polymerization (ATRP) with the reagent, α‐chlorophenylacetyl chloride. The macroinitiator was used for the polymerization of styrene (S) and methyl methacrylate (MMA) to give PS‐block‐PC‐block‐PS and PMMA‐block‐PC‐block‐PMMA triblock copolymers. These block copolymers were characterized by NMR and GPC. When styrene and methyl methacrylate were used in large excess, significant shifts toward high molecular weights were observed with quantitative consumption of the macroinitiator. Several ligands were studied in combination with CuCl as the ATRP catalyst. Kinetic studies reveal the controlled nature of the polymerization reaction for all the ligands used.

Formation of a bifunctional ATRP macroinitiator by esterification of bis(hydroxy)telechelic PC with α‐chlorophenylacetyl chloride.  相似文献   

55.
A case of a male infant with several congenital anomalies combined with an interstitial deletion of the long arm of chromosome no. 5 is presented. The symptoms of the infant were compared to five previous reported cases with similar interstitial deletions in 5q.  相似文献   
56.
The previously described site-selected P-element mutagenesis of a Drosophila gene encoding the regulatory subunit of cAMP-dependent protein kinase generates mutants that have defective behavior in the olfactory learning test. Here we describe the effect of the same mutations in a courtship conditioning assay. Wild-type males can distinguish between virgin females (which they court vigorously), and fertilized females (which they court less vigorously). After exposure to fertilized females, wild-type males modify their behavior by decreasing courtship to subsequent target virgins, an effect that may last for many hours. Like wild-type males, PKA-RI mutant males are also able to distinguish between virgin and fertilized females. PKA-RI males also modify their behavior towards virgin females after prior exposure to a fertilized female, but such an effect is short-lived, suggesting a defect in memory rather than learning. We also show that under these conditions the behavior of PKA-RI males is similar to that of amnesiac, dunce and rutabaga males.  相似文献   
57.
An in vitro rat muscle preparation is described that can contract at rates of 12-240 twitches/min. Maximum dF/dt paralleled maximum twitch tension, their ratio being constant at approximately 8 ms for contraction rates of 12-120 twitches/min. Time to peak tension was 8-13 ms, time to peak dF/dt 5-8 ms, and half-relaxation time 4 ms. These parameters were unaffected by rate of contraction or duration of isometric work. Differential ATPase staining demonstrated that 60-65% of the fibers were fast-twitch white, 20% fast-twitch red, and 15% slow-twitch red. The preponderance of fast-twitch fibers correlated with the observed mechanical performance of the muscle. Muscles contracting for 60 min at rates up to 48 twitches/min maintained total adenine nucleotide content (ATP, ADP, AMP) at near resting levels. At higher twitch rates (72-240 twitches/min), total adenine nucleotide content decreased 40%, reflecting exclusively a fall in ATP in the presence of adequate phosphocreatine stores. Adequate oxygenation was reflected by lactate-to-pyruvate ratios in the range of 11-15 at all rates of contraction.  相似文献   
58.
The role of blue cones as well as the pathways they supply (collectively called the "blue mechanism") is evaluated by comparing ordinary wavelength discrimination functions with those obtained using two methods designed to inhibit the blue mechanism selectively. These methods use a just-noticeable-border criterion (JNB), instead of the usual one of just-noticeable-difference, and a yellow preadapting field to induce transient tritanopia. Without transient tritanopia, the data obtained using the just-noticeable-border criterion reveal a small contribution of the blue mechanism to wavelength discrimination. Transient tritanopia, with JNB, produces an additional selective loss of wavelength discrimination in a spectral region flanking 460 nm, which yields a function resembling those for tritanopes previously examined.  相似文献   
59.
Normal cerebrospinal fluid pressure in the newborn   总被引:2,自引:0,他引:2  
Lumbar CSF pressure (CSFP) was measured on 61 occasions, in 49 babies undergoing lumbar puncture as part of a septic screen, by means of Gaeltec pressure transducers. In normal circumstances, intracranial pressure (ICP) has the same value. Measurements were made when the baby was horizontal and quiet, with the head deflexed. For acceptance of the measurement, it was essential for the CSF to be clear and to show pressure pulses with respiration, heartbeat and jugular occlusion. The mean CSFP and standard deviation were 2.8 +/- 1.4 mm Hg (3.8 +/- 1.9 cm water), with a normal range of 0 to 5.7 mm Hg (0 to 7.6 cm water). This value is similar to previous reports of CSFP measured invasively in infants, but is much lower than the "ICP" established noninvasively. No relationship was found between birthweight, gestational age, current weight, postmenstrual age, or postnatal age and CSFP.  相似文献   
60.
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