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61.
RW McCallum JD Chen Z Lin BD Schirmer RD Williams RA Ross 《Canadian Metallurgical Quarterly》1998,114(3):456-461
BACKGROUND & AIMS: No effective treatment is available for patients with gastroparesis refractory to standard medical therapy. The aim of this study was to investigate the effects of gastric pacing on gastric electrical activity, gastric emptying, and symptoms in patients with gastroparesis. METHODS: Nine patients with gastroparesis participated in this study. Four pairs of cardiac pacing wires were implanted on the serosa of the stomach. The protocol consisted of two portions: a temporary inpatient study period and an outpatient study for a period of 1 month or more. RESULTS: Gastric pacing entrained the gastric slow wave in all subjects and converted tachygastria in 2 patients into regular 3-cpm slow waves. Gastric emptying was significantly improved after the outpatient treatment with gastric pacing. The gastric retention at 2 hours was reduced from 77.0% +/- 3.3% to 56.6% +/- 8.6% (P < 0.05). Symptoms of gastroparesis were substantially reduced at the end of the outpatient treatment (1.51 +/- 0.46 vs. 2.84 +/- 0.61; P < 0.04). Eight of 9 patients no longer relied on jejunostomy tube feeding, and no adverse events were noted related to the pacing unit. CONCLUSIONS: Gastric pacing seems to be able to improve symptoms of gastroparesis and to accelerate gastric emptying in patients with gastroparesis. More controlled studies are necessary to further investigate the role of gastric pacing in clinical practice. 相似文献
62.
正我们告诉大家,如何综合运用Adobe Camera Raw与Photoshop的各项功能,打造一幅完美的具备专业效果的肖像照片。软件准备:Photoshop CS6学习目标:使用特殊模糊滤镜在保留细节的前提下美化皮肤,使用快速选择工具选择并美白牙齿和眼睛。操作耗时:15分钟 相似文献
63.
Britt Van Renterghem Agnieszka Wozniak Patricia Garrido Castro Patrick Franken Nora Pencheva Raf Sciot Patrick Schffski 《International journal of molecular sciences》2022,23(14)
Doxorubicin (doxo) remains the standard of care for patients with advanced soft tissue sarcoma (STS), even though response rates to doxo are only around 14% to 18%. We evaluated enapotamab vedotin (EnaV), an AXL-specific antibody-drug conjugate (ADC), in a panel of STS patient-derived xenografts (PDX). Eight models representing multiple STS subtypes were selected from our STS PDX platform (n = 45) by AXL immunostaining on archived passages. Models were expanded by unilateral transplantation of tumor tissue into the left flank of 20 NMRI nu/nu mice. Once tumors were established, mice were randomized into an EnaV treatment group, or a group treated with isotype control ADC. Treatment efficacy was assessed by tumor volume evaluation, survival analysis, and histological evaluation of tumors, and associated with AXL expression. EnaV demonstrated significant tumor growth delay, regression, and/or prolonged survival compared to isotype control ADC in 5/8 STS PDX models investigated. Experimental passages of responding models were all found positive for AXL at varying levels, but no linear relationship could be identified between the level of expression and level of response to EnaV. One model was found negative for AXL on experimental passage and did not respond to EnaV. This study provides a preclinical rationale for the evaluation of AXL-targeting ADCs in the treatment of AXL-expressing sarcomas. 相似文献
64.
65.
M. H. Miles K. L. Devries A. D. Britt W. B. Moniz 《Propellants, Explosives, Pyrotechnics》1982,7(4):100-106
Efforts to generate detectable concentrations of free radicals in explosives, binders, and their mixtures are described. Radicals were readily produced in polycaprolactone and polyethylene glycol binders at liquid nitrogen temperature using stresses as low as 0.4 kbar. These radicals were all of the peroxy type, and presumably formed by reaction of mechano-radicals with oxygen present in the polymer. No mechano-radicals were observed from HMX or RDX using samples cooled to liquid nitrogen temperature and applied stresses up to 4 kbar. In neither impacted samples that failed to explode nor the residues remaining after a partial explosion were radicals detected by ESR. Low temperature γ-irradiation of these materials was also carried out. Free radical signals originating in both the polymer and the explosive could be identified. The reactivity of NO2 radicals from γ-irradiated HMX is enhanced in the presence of binder. In γ-irradiated HMX/polycaprolactone mixtures, the NO2 radical anneals rapidly at 150 K, versus 240 K for HMX alone. Evidence is presented to suggest that the relatively stable NO2 radical (such as produced by γ-irradiation) in HMX does not play a dominant role in mechanical initiation. 相似文献
67.
68.
Adiabatic demagnetization refrigerators have been built and installed in small portable liquid helium cryostats to test the feasibility of this method of cooling infrared bolometric detectors to temperatures below 0.3K. Performance has been achieved which suggests that bolometer temperatures of 0.2K can be maintained for periods of ~60 hours. Applications to sensitive infrared detection from ground based telescopes and space satellites are discussed. Design data are given which permit the evaluation of refrigerator performance for a variety of design parameters. 相似文献
69.
RD Howard RS Martens SA Innis JM Drnevich J Hale 《Canadian Metallurgical Quarterly》1998,55(5):1151-1163
A sexual size dimorphism usually occurs when size-dependent reproductive advantages exist in only one sex. Studies on Japanese medaka, Oryzias latipes, have demonstrated reproductive size advantages in females but not in males, even though males and females are similar in body size. We conducted mate-choice and mate-copying tests in which a female could first associate with, then mate with, either a large (>/=1 sd+X standard length) or a small male (=1 sd-X standard length). Large males obtained a mating advantage in both tests, and both mate choice and mate competition influenced their mating success. In the majority of trials, females associated with large males. Association preferences of females corresponded to their mating preferences when mate competition between males was weak; however, when mate competition was strong, large males obtained almost every mating regardless of female association preference. Preference for large males may provide females with a reproductive advantage if males mate multiply because small males become sperm-depleted sooner than large males. We found no indication that females copied the mating decisions of other females. Repeatability of female mating preference was low, not because females mated at random with respect to male size, but because most females consistently preferred large males. We also conducted mating tests at four density levels and found that large males maintained their mating advantage relative to small males at all densities. Thus, male and female medaka may be similar in body size because large size provides a fecundity advantage for females, as demonstrated in previous studies, and large size provides a mating advantage for males, as demonstrated in our study. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour. 相似文献
70.
H Weiler-Guettler WC Aird H Rayburn M Husain RD Rosenberg 《Canadian Metallurgical Quarterly》1996,122(7):2271-2281
Embryonic lethality of thrombomodulin-deficient mice has indicated an essential role for this regulator of blood coagulation in murine development. Here, the embryonic expression pattern of thrombomodulin was defined by surveying beta-galactosidase activity in a mouse strain in which the reporter gene was placed under the regulatory control of the endogenous thrombomodulin promoter via homologous recombination in embryonic stem cells. The murine trophoblast was identified as a previously unrecognized anatomical site where TM expression is conserved between humans and mice and may exert a critical function during postimplantation development. Targeted reporter gene expression in mesodermal precursors of the endothelial cell lineage defined thrombomodulin as an early marker of vascular differentiation. Analysis of the thrombomodulin promoter in differentiating ES cells and in transgenic mice provided evidence for a disparate and cell type-specific gene regulatory control mechanism in the parietal yolk sac. The thrombomodulin promoter as defined in this study will allow the targeting of gene expression to the parietal yolk sac of transgenic mice and the initiation of investigations into the role of parietal endoderm in placental function. 相似文献