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Conclusions Using a dynamic assembly of the Mikrogaz type for the preparation of gas mixtures of known composition, the sorption of hydrogen chloride and of ammonia has been studied in the concentration range from 0.5 to 1000 mg/m3, under dynamic conditions on the nonwoven chemisorptive fibrous material VION, type KN-1. Regimes for the desorption of these materials and regeneration of the sorbent have been selected.The possibility of fine clean-up of gas discharges of hydrogen chloride and of ammonia on VION KN-1 has been demonstrated, plus the conditions for effecting it, as well as the possibility of using this material for mean shift and mean daily quantitative air sampling.Translated from Khimicheskie Volokna, No. 6, pp. 48–50, November–December, 1987.  相似文献   
83.
Anger and related emotions have been identified as triggers in substance use. Forgiveness therapy (FT) targets anger, anxiety, and depression as foci of treatment. Fourteen patients with substance dependence from a local residential treatment facility were randomly assigned to and completed either 12 approximately twice-weekly sessions of individual FT or 12 approximately twice-weekly sessions of an alternative individual treatment based on routine drug and alcohol therapy topics. Participants who completed FT had significantly more improvement in total and trait anger, depression, total and trait anxiety, self-esteem, forgiveness, and vulnerability to drug use than did the alternative treatment group. Most benefits of FT remained significant at 4-month follow-up. These results support FT as an efficacious newly developed model for residential drug rehabilitation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
在近几年来,人们倾向于利用Rock-Eval热解法的氢指数来评价烃源岩,而忽略了用干酪根H/C比值评价烃源岩的优点,Rock-Eval热解法能快速,廉价、定量(mgHC/g岩石)地给出岩石中干酪根的热解数据,由于在数据分布上的普遍分散性,一般人们认为Rock-Eval热解法对烃源岩评价是一种筛选评价,描述了在烃源岩评价中应用H/C比值的优点,并确定了H/C比值与热成熟度,有机质转化率和排油量之间新的相关性。热解干酪根的H/C比值与I型,II型干酪根的热转化率程度存在一定的相关性,定量计算的氢和碳损失与加水热解实验中的损失具有很好的一致性,表明干格根H/C比值可作为干酪根端元热成熟度的一个好的指标,如果现在原始H/C比值确定,那么这些数据同时也为评价有机质转化率提供了一种新的方法,现在H/C比值可通过微相有机质分析测试,对于生油源岩,I型未熟干酪根的H/C比值为1.35-1.50,II型H/C比值为1.20-1.35。在加热水解实验中,油的排出量与H/C比值之间的相关性可为勘探工作者提供一种快速评价油的排出量的方法。依据加水热解实验,测试的H/C比值和计算的原始TOC(总有机碳)对Williston盆地(Bakken页岩),Los Angeles盆地(Nodulard页岩)和Illionis盆地(New Albany页岩)的成熟烃源岩进行了初步体积估算,其结果于已发表的该盆地油的评价值非常吻合。  相似文献   
85.
BACKGROUND: Advance directives have not been uniformly used by different segments of the US population and studies have consistently shown a lower prevalence of advance directives among African Americans and Hispanics compared with non-Hispanic whites. OBJECTIVE: To examine barriers to completion of health care proxies for different ethnic groups. METHODS: One hundred ninety-seven subjects aged 65 years or older self-identified as African American (n = 65), Hispanic (n = 65), or non-Hispanic white (n = 67) attending a geriatrics and internal medicine outpatient clinic of a large New York City teaching hospital were administered a questionnaire. Questionnaires were developed to examine potential barriers to completion of health care proxies. Barriers were drawn from the literature and from focus groups. RESULTS: Significant predictors of proxy completion using logistic regression analysis included knowledge of health care proxies, availability of a health care agent, exposure to mechanical ventilation, age, and self-reported health status as fair to poor. Subjects who believed that a health care agent was irrelevant in the setting of involved family were significantly less likely to have completed a health care proxy. Although there were significant differences in the baseline completion rates of health care proxies for the 3 ethnic groups, ethnicity did not predict prior appointment of a health care agent in multivariate analysis. CONCLUSIONS: Differences in health care proxy completion rates across white, African American, and Hispanic elderly individuals in this New York City population seem to be related to potentially reversible barriers such as lack of knowledge and the perceived irrelevance of advance directives in the setting of involved family. Enhanced educational efforts of both health care personnel and patients could increase the rate of formal health care proxy appointment.  相似文献   
86.
Placebo treatments in psychotherapy cannot adequately control for all common factors, which thereby attenuates their effects vis-à-vis active treatments. In this study, the authors used meta-analytic procedures to test one possible factor contributing to the attenuation of effects: structural inequalities between placebo and active treatments. Structural aspects of the placebo included number and duration of sessions, training of therapist, format of therapy, and restriction of topics. Results indicate that comparisons between active treatments and structurally inequivalent placebos produced larger effects than comparisons between active treatments and structurally equivalent placebos: moreover, the latter comparison produced negligible effects, indicating that active treatments were not demonstrably superior to well-designed placebos. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
Linear amplification, or primer directed single-strand DNA synthesis, is commonly used in applications such as cycle sequencing and mapping replication block sites in DNA. Although linear amplification reactions would be expected to synthesize full-length single-stranded DNA, the synthesis is often prematurely terminated. We describe the optimization of a linear amplification protocol for synthesizing a full-length (985-nt) single-stranded pBR322 segment. The enzyme activities of five DNA polymerases commonly used in PCR amplification, namely, AmpliTaq, Stoffel fragment, Tth, Pfu, and Vent, were tested either singly or in combination. The results indicate that the additive action of small amounts of proofreading DNA polymerases to a nick-translating polymerase is optimum for linear amplification. From these results, a linear amplification protocol was developed to map DNA synthesis-blocking sites generated by the reaction of (+/-) anti-benzo[a]pyrene-7,8-diol-9,10-epoxide, or anti- or syn-dibenzo[a,l]pyrene-9,10-diol-11,12-epoxide with H-ras DNA surrounding the oncogenic codon 61 region. The results indicate that the central A of H-ras codon 61 (CAA) reacts with these polycyclic aromatic hydrocarbons.  相似文献   
88.
Malignant gliomas, including glioblastomas, are extremely difficult to treat. The median survival for glioblastoma patients with optimal therapeutic intervention is 15 months. We developed a novel MAO‐B‐selectively activated prodrug, N,N‐bis(2‐chloroethyl)‐2‐(1‐methyl‐1,2,3,6‐tetrahydropyridin‐4‐yl)propanamide (MP‐MUS), for the treatment of gliomas based on 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP). The design of neutral MP‐MUS involved the use of a seeker molecule capable of binding to mitochondrial MAO‐B, which is up‐regulated ≥fourfold in glioma cells. Once the binding occurs, MP‐MUS is converted into a positively charged moiety, P+‐MUS, which accumulates inside mitochondria at a theoretical maximal value of 1000:1 gradient. The LD50 of MP‐MUS against glioma cells is 75 μM , which is two‐ to threefold more potent than temozolomide, a primary drug for gliomas. Importantly, MP‐MUS was found to be selectively toxic toward glioma cells. In the concentration range of 150–180 μM MP‐MUS killed 90–95 % of glioma cells, but stimulated the growth of normal human astrocytes. Moreover, maturation of MP‐MUS is highly dependent on MAO‐B, and inhibition of MAO‐B activity with selegiline protected human glioma cells from apoptosis.  相似文献   
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