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  1. Article ; Online: Menopausal Hormone Therapy, Age, and Chronic Diseases: Perspectives on Statistical Trends.

    Bolton, Judy L

    Chemical research in toxicology

    2016  Volume 29, Issue 10, Page(s) 1583–1590

    Abstract: The release of the Women's Health Initiative (WHI) study in 2002 was a shock to the medical community. Hormone therapy (HT) had generally been considered to be highly beneficial for postmenopausal women since it was the gold standard for relief of ... ...

    Abstract The release of the Women's Health Initiative (WHI) study in 2002 was a shock to the medical community. Hormone therapy (HT) had generally been considered to be highly beneficial for postmenopausal women since it was the gold standard for relief of menopausal symptoms (hot flashes, night sweats, vaginal atrophy) and it was thought to protect women from osteoporosis, heart disease, and cognitive decline and to generally improve quality of life. However, WHI showed a statistically significant increase in a number of disease states, including breast cancer, cardiovascular disease, and stroke. One problem with the WHI study was that the average age of women in the study was 63, which is considerably older than the age at which most women enter menopause (about 51). The timing hypothesis attempts to rationalize the effect of age on response to HT and risk of various diseases. The data suggests that younger women (50-60) may be protected from heart disease with only a slight increase in breast cancer risk. In contrast, older women (>65) are more susceptible to breast cancer and heart disease and should avoid HT. This Perspective on Statistical Trends evaluates the current data on HT and risk for chronic diseases as a function of age.
    MeSH term(s) Age Factors ; Breast Neoplasms/drug therapy ; Cardiovascular Diseases/drug therapy ; Estrogen Replacement Therapy ; Female ; Humans ; Stroke/drug therapy
    Language English
    Publishing date 2016-09-26
    Publishing country United States
    Document type Journal Article ; Review ; Research Support, N.I.H., Extramural
    ZDB-ID 639353-6
    ISSN 1520-5010 ; 0893-228X
    ISSN (online) 1520-5010
    ISSN 0893-228X
    DOI 10.1021/acs.chemrestox.6b00272
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Quinone Methide Bioactivation Pathway: Contribution to Toxicity and/or Cytoprotection?

    Bolton, Judy L

    Current organic chemistry

    2014  Volume 18, Issue 1, Page(s) 61–69

    Abstract: The formation of quinone methides (QMs) from either direct 2-electron oxidation of 2- or 4-alkylphenols, isomerization ... ...

    Abstract The formation of quinone methides (QMs) from either direct 2-electron oxidation of 2- or 4-alkylphenols, isomerization of
    Language English
    Publishing date 2014-10-27
    Publishing country Netherlands
    Document type Journal Article
    ISSN 1385-2728
    ISSN 1385-2728
    DOI 10.2174/138527281801140121123046
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Masking Between Reserved Alarm Sounds of the IEC 60601-1-8 International Medical Alarm Standard: A Systematic, Formal Analysis.

    Bolton, Matthew L / Edworthy, Judy R / Boyd, Andrew D

    Human factors

    2020  Volume 64, Issue 5, Page(s) 835–851

    Abstract: Objective: In this work, we systematically evaluated the reserved alarm sounds of the IEC 60601-1-8 international medical alarm standard to determine when and how they can be totally and partially masked.: Background: IEC 60601-1-8 gives engineers ... ...

    Abstract Objective: In this work, we systematically evaluated the reserved alarm sounds of the IEC 60601-1-8 international medical alarm standard to determine when and how they can be totally and partially masked.
    Background: IEC 60601-1-8 gives engineers instruction for creating human-perceivable auditory medical alarms. This includes reserved alarm sounds: common types of alarms where each is a tonal melody. Even when this standard is honored, practitioners still fail to hear alarms, causing practitioner nonresponse and, thus, potential patient harm. Simultaneous masking, a condition where one or more alarms is imperceptible in the presence of other concurrently sounding alarms due to limitations of the human sensory system, is partially responsible for this.
    Methods: In this research, we use automated proof techniques to determine if masking can occur in a modeled configuration of medical alarms. This allows us to determine when and how reserved alarm sound can mask other reserved alarms and to explore parameters to address discovered problems.
    Results: We report the minimum number of other alarm sounds it takes to both totally and partially mask each of the high-, medium-, and low-priority alarm sounds from the standard.
    Conclusions: Significant masking problems were found for both the total and partial masking of high-, medium-, and low-priority reserved alarm sounds.
    Application: We show that discovered problems can be mitigated by setting alarm volumes to standard values based on priority level and by randomizing the timing of alarm tones.
    MeSH term(s) Clinical Alarms ; Humans ; Monitoring, Physiologic ; Sound
    Language English
    Publishing date 2020-12-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 212725-8
    ISSN 1547-8181 ; 0018-7208
    ISSN (online) 1547-8181
    ISSN 0018-7208
    DOI 10.1177/0018720820967596
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Formation and Biological Targets of Quinones: Cytotoxic versus Cytoprotective Effects.

    Bolton, Judy L / Dunlap, Tareisha

    Chemical research in toxicology

    2017  Volume 30, Issue 1, Page(s) 13–37

    Abstract: Quinones represent a class of toxicological intermediates, which can create a variety of hazardous effects in vivo including, acute cytotoxicity, immunotoxicity, and carcinogenesis. In contrast, quinones can induce cytoprotection through the induction of ...

    Abstract Quinones represent a class of toxicological intermediates, which can create a variety of hazardous effects in vivo including, acute cytotoxicity, immunotoxicity, and carcinogenesis. In contrast, quinones can induce cytoprotection through the induction of detoxification enzymes, anti-inflammatory activities, and modification of redox status. The mechanisms by which quinones cause these effects can be quite complex. The various biological targets of quinones depend on their rate and site of formation and their reactivity. Quinones are formed through a variety of mechanisms from simple oxidation of catechols/hydroquinones catalyzed by a variety of oxidative enzymes and metal ions to more complex mechanisms involving initial P450-catalyzed hydroxylation reactions followed by two-electron oxidation. Quinones are Michael acceptors, and modification of cellular processes could occur through alkylation of crucial cellular proteins and/or DNA. Alternatively, quinones are highly redox active molecules which can redox cycle with their semiquinone radical anions leading to the formation of reactive oxygen species (ROS) including superoxide, hydrogen peroxide, and ultimately the hydroxyl radical. Production of ROS can alter redox balance within cells through the formation of oxidized cellular macromolecules including lipids, proteins, and DNA. This perspective explores the varied biological targets of quinones including GSH, NADPH, protein sulfhydryls [heat shock proteins, P450s, cyclooxygenase-2 (COX-2), glutathione S-transferase (GST), NAD(P)H:quinone oxidoreductase 1, (NQO1), kelch-like ECH-associated protein 1 (Keap1), IκB kinase (IKK), and arylhydrocarbon receptor (AhR)], and DNA. The evidence strongly suggests that the numerous mechanisms of quinone modulations (i.e., alkylation versus oxidative stress) can be correlated with the known pathology/cytoprotection of the parent compound(s) that is best described by an inverse U-shaped dose-response curve.
    MeSH term(s) Animals ; Cytoprotection ; Cytotoxins/chemistry ; Cytotoxins/pharmacology ; Cytotoxins/toxicity ; Humans ; Quinones/chemistry ; Quinones/pharmacology ; Quinones/toxicity
    Chemical Substances Cytotoxins ; Quinones
    Language English
    Publishing date 2017--17
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 639353-6
    ISSN 1520-5010 ; 0893-228X
    ISSN (online) 1520-5010
    ISSN 0893-228X
    DOI 10.1021/acs.chemrestox.6b00256
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Formation and biological targets of botanical o-quinones.

    Bolton, Judy L / Dunlap, Tareisha L / Dietz, Birgit M

    Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association

    2018  Volume 120, Page(s) 700–707

    Abstract: The formation of o-quinones from direct 2-electron oxidation of catechols and/or two successive one electron oxidations could explain the cytotoxic/genotoxic and/or chemopreventive effects of several phenolic botanical extracts. For example, poison ivy ... ...

    Abstract The formation of o-quinones from direct 2-electron oxidation of catechols and/or two successive one electron oxidations could explain the cytotoxic/genotoxic and/or chemopreventive effects of several phenolic botanical extracts. For example, poison ivy contains urushiol, an oily mixture, which is oxidized to various o-quinones likely resulting in skin toxicity through oxidative stress and alkylation mechanisms resulting in immune responses. Green tea contains catechins which are directly oxidized to o-quinones by various oxidative enzymes. Alternatively, phenolic botanicals could be o-hydroxylated by P450 to form catechols in vivo which are oxidized to o-quinones. Examples include, resveratrol which is oxidized to piceatannol and further oxidized to the o-quinone. Finally, botanical o-quinones can be formed by O-dealkylation of O-alkoxy groups or methylenedioxy rings resulting in catechols which are further oxidized to o-quinones. Examples include safrole, eugenol, podophyllotoxin and etoposide, as well as methysticin. Once formed these o-quinones have a variety of biological targets in vivo resulting in various biological effects ranging from chemoprevention -> no effect -> toxicity. This U-shaped biological effect curve has been described for a number of reactive intermediates including o-quinones. The current review summarizes the latest data on the formation and biological targets of botanical o-quinones.
    MeSH term(s) Activation, Metabolic ; Alkylation ; DNA/chemistry ; Glutathione/chemistry ; Hydroxylation ; Oxidation-Reduction ; Plants/chemistry ; Proteins/chemistry ; Quinones/chemical synthesis ; Quinones/chemistry ; Quinones/pharmacology
    Chemical Substances Proteins ; Quinones ; DNA (9007-49-2) ; Glutathione (GAN16C9B8O)
    Language English
    Publishing date 2018-07-29
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 782617-5
    ISSN 1873-6351 ; 0278-6915
    ISSN (online) 1873-6351
    ISSN 0278-6915
    DOI 10.1016/j.fct.2018.07.050
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Breast cancer prevention with liquiritigenin from licorice through the inhibition of aromatase and protein biosynthesis in high-risk women's breast tissue.

    Hajirahimkhan, Atieh / Howell, Caitlin / Bartom, Elizabeth T / Dong, Huali / Lantvit, Daniel D / Xuei, Xiaoling / Chen, Shao-Nong / Pauli, Guido F / Bolton, Judy L / Clare, Susan E / Khan, Seema A / Dietz, Birgit M

    Scientific reports

    2023  Volume 13, Issue 1, Page(s) 8734

    Abstract: Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer prevention. ...

    Abstract Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer prevention. Natural products such as hops (Humulus lupulus) and three pharmacopeial licorice (Glycyrrhiza) species have demonstrated estrogenic and chemopreventive properties, but little is known regarding their effects on aromatase expression and activity as well as pro-proliferation pathways in human breast tissue. We show that Gycyrrhiza inflata (GI) has the highest aromatase inhibition potency among these plant extracts. Moreover, phytoestrogens such as liquiritigenin which is common in all licorice species have potent aromatase inhibitory activity, which is further supported by computational docking of their structures in the binding pocket of aromatase. In addition, GI extract and liquiritigenin suppress aromatase expression in the breast tissue of high-risk postmenopausal women. Although liquiritigenin has estrogenic effects in vitro, with preferential activity through estrogen receptor (ER)-β, it reduces estradiol-induced uterine growth in vivo. It downregulates RNA translation, protein biosynthesis, and metabolism in high-risk women's breast tissue. Finally, it reduces the rate of MCF-7 cell proliferation, with repeated dosing. Collectively, these data suggest that liquiritigenin has breast cancer prevention potential for high-risk postmenopausal women.
    MeSH term(s) Female ; Humans ; Breast Neoplasms/prevention & control ; Breast Neoplasms/metabolism ; Aromatase/metabolism ; Aromatase Inhibitors/pharmacology ; Estrogens/metabolism ; Glycyrrhiza/chemistry ; Estrogen Receptor beta/metabolism ; Protein Biosynthesis
    Chemical Substances liquiritigenin (T194LKP9W6) ; Aromatase (EC 1.14.14.1) ; Aromatase Inhibitors ; Estrogens ; Estrogen Receptor beta
    Language English
    Publishing date 2023-05-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-023-34762-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Breast cancer prevention with liquiritigenin from licorice through the inhibition of aromatase and protein biosynthesis in high-risk women’s breast tissue

    Atieh Hajirahimkhan / Caitlin Howell / Elizabeth T. Bartom / Huali Dong / Daniel D. Lantvit / Xiaoling Xuei / Shao-Nong Chen / Guido F. Pauli / Judy L. Bolton / Susan E. Clare / Seema A. Khan / Birgit M. Dietz

    Scientific Reports, Vol 13, Iss 1, Pp 1-

    2023  Volume 14

    Abstract: Abstract Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer ... ...

    Abstract Abstract Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer prevention. Natural products such as hops (Humulus lupulus) and three pharmacopeial licorice (Glycyrrhiza) species have demonstrated estrogenic and chemopreventive properties, but little is known regarding their effects on aromatase expression and activity as well as pro-proliferation pathways in human breast tissue. We show that Gycyrrhiza inflata (GI) has the highest aromatase inhibition potency among these plant extracts. Moreover, phytoestrogens such as liquiritigenin which is common in all licorice species have potent aromatase inhibitory activity, which is further supported by computational docking of their structures in the binding pocket of aromatase. In addition, GI extract and liquiritigenin suppress aromatase expression in the breast tissue of high-risk postmenopausal women. Although liquiritigenin has estrogenic effects in vitro, with preferential activity through estrogen receptor (ER)-β, it reduces estradiol-induced uterine growth in vivo. It downregulates RNA translation, protein biosynthesis, and metabolism in high-risk women’s breast tissue. Finally, it reduces the rate of MCF-7 cell proliferation, with repeated dosing. Collectively, these data suggest that liquiritigenin has breast cancer prevention potential for high-risk postmenopausal women.
    Keywords Medicine ; R ; Science ; Q
    Subject code 610 ; 616
    Language English
    Publishing date 2023-05-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: DESIGNER fraction concept unmasks minor bioactive constituents in red clover (Trifolium pratense L.).

    Hitzman, Ryan / Malca-Garcia, Gonzalo R / Howell, Caitlin / Park, Hyun-Young / Friesen, J Brent / Dong, Huali / Dunlap, Tareisha / McAlpine, James B / Vollmer, Guenter / Bosland, Maarten C / Nikolić, Dejan / Lankin, David C / Chen, Shao-Nong / Bolton, Judy L / Pauli, Guido F / Dietz, Birgit M

    Phytochemistry

    2023  Volume 214, Page(s) 113789

    Abstract: In botanical extracts, highly abundant constituents can mask or dilute the effects of other, and often, more relevant biologically active compounds. To facilitate the rational chemical and biological assessment of these natural products with wide usage ... ...

    Abstract In botanical extracts, highly abundant constituents can mask or dilute the effects of other, and often, more relevant biologically active compounds. To facilitate the rational chemical and biological assessment of these natural products with wide usage in human health, we introduced the DESIGNER approach of Depleting and Enriching Selective Ingredients to Generate Normalized Extract Resources. The present study applied this concept to clinical Red Clover Extract (RCE) and combined phytochemical and biological methodology to help rationalize the utility of RCE supplements for symptom management in postmenopausal women. Previous work has demonstrated that RCE reduces estrogen detoxification pathways in breast cancer cells (MCF-7) and, thus, may serve to negatively affect estrogen metabolism-induced chemical carcinogenesis. Clinical RCE contains ca. 30% of biochanin A and formononetin, which potentially mask activities of less abundant compounds. These two isoflavonoids are aryl hydrocarbon receptor (AhR) agonists that activate P450 1A1, responsible for estrogen detoxification, and P450 1B1, producing genotoxic estrogen metabolites in female breast cells. Clinical RCE also contains the potent phytoestrogen, genistein, that downregulates P450 1A1, thereby reducing estrogen detoxification. To identify less abundant bioactive constituents, countercurrent separation (CCS) of a clinical RCE yielded selective lipophilic to hydrophilic metabolites in six enriched DESIGNER fractions (DFs 01-06). Unlike solid-phase chromatography, CCS prevented any potential loss of minor constituents or residual complexity (RC) and enabled the polarity-based enrichment of certain constituents. Systematic analysis of estrogen detoxification pathways (ERα-degradation, AhR activation, CYP1A1/CYP1B1 induction and activity) of the DFs uncovered masked bioactivity of minor/less abundant constituents including irilone. These data will allow the optimization of RCE with respect to estrogen detoxification properties. The DFs revealed distinct biological activities between less abundant bioactives. The present results can inspire future carefully designed extracts with phytochemical profiles that are optimized to increase in estrogen detoxification pathways and, thereby, promote resilience in women with high-risk for breast cancer. The DESIGNER approach helps to establish links between complex chemical makeup, botanical safety and possible efficacy parameters, yields candidate DFs for (pre)clinical studies, and reveals the contribution of minor phytoconstituents to the overall safety and bioactivity of botanicals, such as resilience promoting activities relevant to women's health.
    MeSH term(s) Female ; Humans ; Trifolium/chemistry ; Trifolium/metabolism ; Isoflavones/pharmacology ; Isoflavones/metabolism ; Estrogens ; Plant Extracts/pharmacology ; Plant Extracts/chemistry ; Breast Neoplasms/drug therapy
    Chemical Substances Isoflavones ; Estrogens ; Plant Extracts
    Language English
    Publishing date 2023-07-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 208884-8
    ISSN 1873-3700 ; 0031-9422
    ISSN (online) 1873-3700
    ISSN 0031-9422
    DOI 10.1016/j.phytochem.2023.113789
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: An Experimental Validation of Masking in IEC 60601-1-8:2006-Compliant Alarm Sounds.

    Bolton, Matthew L / Zheng, Xi / Li, Meng / Edworthy, Judy Reed / Boyd, Andrew D

    Human factors

    2019  Volume 62, Issue 6, Page(s) 954–972

    Abstract: Objective: This research investigated whether the psychoacoustics of simultaneous masking, which are integral to a model-checking-based method, previously developed for detecting perceivability problems in alarm configurations, could predict when IEC ... ...

    Abstract Objective: This research investigated whether the psychoacoustics of simultaneous masking, which are integral to a model-checking-based method, previously developed for detecting perceivability problems in alarm configurations, could predict when IEC 60601-1-8-compliant medical alarm sounds are audible.
    Background: The tonal nature of sounds prescribed by IEC 60601-1-8 makes them potentially susceptible to simultaneous masking: where concurrent sounds render one or more inaudible due to human sensory limitations. No work has experimentally assessed whether the psychoacoustics of simultaneous masking accurately predict IEC 60601-1-8 alarm perceivability.
    Method: In two signal detection experiments, 28 nursing students judged whether alarm sounds were present in collections of concurrently sounding standard-compliant tones. The first experiment used alarm sounds with single-frequency (primary harmonic) tones. The second experiment's sounds included the additional, standard-required frequencies (often called subharmonics).
    Results: Miss rates were significantly higher and sensitivity was significantly lower for the masking condition than for the nonmasking one. There were no significant differences between the measures of the two experiments.
    Conclusion: These results validate the predictions of the psychoacoustics of simultaneous masking for medical alarms and the masking detection capabilities of our method that relies on them. The results also show that masking of an alarm's primary harmonic is sufficient to make an alarm sound indistinguishable.
    Application: Findings have profound implications for medical alarm design, the international standard, and masking detection methods.
    MeSH term(s) Humans ; Psychoacoustics ; Sound
    Language English
    Publishing date 2019-08-14
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 212725-8
    ISSN 1547-8181 ; 0018-7208
    ISSN (online) 1547-8181
    ISSN 0018-7208
    DOI 10.1177/0018720819862911
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  10. Article ; Online: 6-Prenylnaringenin from Hops Disrupts ERα-Mediated Downregulation of

    Hitzman, Ryan T / Dunlap, Tareisha L / Howell, Caitlin E / Chen, Shao-Nong / Vollmer, Günter / Pauli, Guido F / Bolton, Judy L / Dietz, Birgit M

    Chemical research in toxicology

    2020  Volume 33, Issue 11, Page(s) 2793–2803

    Abstract: Botanical dietary supplements (BDS) containing hops are sold as women's health supplements due to the potent hop phytoestrogen, 8-prenylnaringenin (8-PN), and the cytoprotective chalcone, xanthohumol. Previous studies have shown a standardized hop ... ...

    Abstract Botanical dietary supplements (BDS) containing hops are sold as women's health supplements due to the potent hop phytoestrogen, 8-prenylnaringenin (8-PN), and the cytoprotective chalcone, xanthohumol. Previous studies have shown a standardized hop extract to beneficially influence chemical estrogen carcinogenesis
    MeSH term(s) Cytochrome P-450 CYP1A1/antagonists & inhibitors ; Cytochrome P-450 CYP1A1/genetics ; Cytochrome P-450 CYP1A1/metabolism ; Down-Regulation/drug effects ; Estrogen Receptor alpha/antagonists & inhibitors ; Estrogen Receptor alpha/metabolism ; Estrogens/adverse effects ; Female ; Flavonoids/chemistry ; Flavonoids/isolation & purification ; Flavonoids/pharmacology ; Humans ; Humulus/chemistry ; Tumor Cells, Cultured
    Chemical Substances 6-prenylnaringenin ; ESR1 protein, human ; Estrogen Receptor alpha ; Estrogens ; Flavonoids ; CYP1A1 protein, human (EC 1.14.14.1) ; Cytochrome P-450 CYP1A1 (EC 1.14.14.1)
    Language English
    Publishing date 2020-10-12
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 639353-6
    ISSN 1520-5010 ; 0893-228X
    ISSN (online) 1520-5010
    ISSN 0893-228X
    DOI 10.1021/acs.chemrestox.0c00194
    Database MEDical Literature Analysis and Retrieval System OnLINE

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