tbuckley/cabot-search huggingface dataset:
Review: Targeting SBP lowering to &lt; 140 mm Hg reduces MACE more than targeting SBP to &gt; 140 in hypertensive patients ≥ 65 y
Authors: Peter W. de Leeuw
Journal: Annals of Internal Medicine (2017)

ACP Journal Club16 May 2017Review: Targeting SBP lowering to < 140 mm Hg reduces MACE more than targeting SBP to > 140 in hypertensive patients ≥ 65 yPeter W. de Leeuw, MDPeter W. de Leeuw, MDMaastricht University Medical Center, Maastricht, The Netherlands (P.W.D.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/ACPJC-2017-166-10-055 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Source CitationBavishi C, Bangalore S, Messerli FH. Outcomes of intensive blood pressure lowering in older hypertensive patients. J Am Coll Cardiol. 2017;69:486-93. https://pubmed.ncbi.nlm.nih.gov/28153104Clinical Impact RatingsGIM/FP/GP: Cardiology: References1 Wei Y, Jin Z, Shen G, et al. Effects of intensive antihypertensive treatment on Chinese hypertensive patients older than 70 years. J Clin Hypertens (Greenwich). 2013;15:420–7. [PMID: 23730991] Google Scholar2 JATOS Study Group. Principal results of the Japanese Trial to Assess Optimal Systolic Blood Pressure in Elderly Hypertensive Patients (JATOS). Hypertens Res. 2008;31:2115–27. [PMID: 19139601] Google Scholar3 Ogihara T, Saruta T, Rakugi H, et al; Valsartan in Elderly Isolated Systolic Hypertension Study Group. Target blood pressure for treatment of isolated systolic hypertension in the elderly: Valsartan in Elderly Isolated Systolic Hypertension Study. Hypertension. 2010;56:196–202. [PMID: 20530299] Google Scholar4 Williamson JD, Supiano MA, Applegate WB, et al; SPRINT Research Group. Intensive vs standard blood pressure control and cardiovascular disease outcomes in adults aged ≥75 years: a randomized clinical trial. JAMA. 2016;315:2673–82. [PMID: 27195814] Google Scholar Author, Article, and Disclosure InformationAffiliations: Maastricht University Medical Center, Maastricht, The Netherlands (P.W.D.)This article was published at Annals.org on 2 May 2017. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics 16 May 2017Volume 166, Issue 10Page: JC55KeywordsBlood pressureClinical trial reportingElderlyHypertensionMyocardial infarctionRelative riskRenal failureSafetySerious adverse eventsSystolic pressure ePublished: 16 May 2017 Issue Published: 16 May 2017 Copyright & PermissionsCopyright © 2017 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...
Individual patients data analysis (IPD) of three randomized studies comparing erlotinib (E) with chemotherapy (CT) in patients with advanced wild-type epidermal growth factor receptor (wtEGFR) non-small cell lung cancer (NSCLC).
Authors: Valter Torri, Masahiko Ando, Eliana Rulli, Irene Claudia Floriani, Tomoya Kawaguchi, Shun-ichi Isa, Vanesa Gregorc, Silvia Novello, Sandro Barni, Michela Cinquini, Silvia Marsoni, Gabriella Farina, Marina Chiara Garassino
Journal: Journal of Clinical Oncology (2015)

8048 Background: While the benefit of EGFR tyrosine kinase inhibitors in EGFR mutated NSCLC patients (pts) is undisputed, their usefulness in wtEGFR pts is still questioned. The TAILOR, DELTA and PROSE trials singularly showed a significant gain in Progression-Free Survival (PFS) favoring CT. We present here the mature results from the IPD analysis of the three studies. Methods: In each trial, pts with wtEGFR stage IIIB/IV NSCLC, progressing after first line platinum-based therapy, were randomized 1:1 to receive either E or CT at standard doses. Primary endpoints of this IPD were PFS and Overall Survival (OS); summary measures were Hazard Ratio (HR) and Difference in Mean Survival Time (DMST), which is the difference in the areas under the Kaplan-Meier curves of two treatment arms. Cox regression analyses were used to estimate the HR. All analyses were stratified by trial. Results: The analysis included all 587 pts randomized into the trials (Overall E/CT 303/284; TAILOR 109/110; DELTA 109/90; PROSE 85/84); 464 deaths and 570 progressions or deaths were observed. Compared with CT, E treatment was associated to an increased risk of both progression (40%) and death (12%) (HR-PFS: 1.40, 95%CI: 1.18-1.65, p < 0.0001; HR-OS: 1.12, 95%CI: 0.93-1.35; p = 0.221). Importantly, patients treated with CT gained 1.6 and 1.5 months, in progression-free and life-time respectively (DMST-PFS 95%CI: 0.6-2.1; DMST-OS 95%CI: -0.5-3.4). Results were preserved after adjustment by age, gender, smoking habit, performance status and histotype. Conclusions: The IPD analysis of TAILOR, DELTA and PROSE conclusively confirm the superiority of CT over E in the disease control of wtEGFR NSCLC patients, and corroborate the original results of each single trial.
Evacetrapib and Cardiovascular Outcomes in High-Risk Vascular Disease
Authors: A Michael Lincoff, Stephen J Nicholls, Jeffrey S Riesmeyer, Philip J Barter, H Bryan Brewer, Keith A A Fox, C Michael Gibson, Christopher Granger, Venu Menon, Gilles Montalescot, Daniel Rader, Alan R Tall, Ellen McErlean, Kathy Wolski, Giacomo Ruotolo, Burkhard Vangerow, Govinda Weerakkody, Shaun G Goodman, Diego Conde, Darren K McGuire, Jose C Nicolau, Jose L Leiva-Pons, Yves Pesant, Weimin Li, David Kandath, Simon Kouz, Naeem Tahirkheli, Denise Mason, Steven E Nissen
Journal: New England Journal of Medicine (2017)

The cholesteryl ester transfer protein inhibitor evacetrapib substantially raises the high-density lipoprotein (HDL) cholesterol level, reduces the low-density lipoprotein (LDL) cholesterol level, and enhances cellular cholesterol efflux capacity. We sought to determine the effect of evacetrapib on major adverse cardiovascular outcomes in patients with high-risk vascular disease.
Transfusion-Associated Acquired Immunodeficiency Syndrome
Authors: Paul M. Feorino, Harold W. Jaffe, Erskine Palmer, Thomas A. Peterman, Donald P. Francis, V.S. Kalyanaraman, Robert A. Weinstein, Rand L. Stoneburner, W. James Alexander, Cathy Raevsky, Jane P. Getchell, Donna Warfield, Harry W. Haverkos, Barbara W. Kilbourne, J.K.A. Nicholson, James W. Curran
Journal: New England Journal of Medicine (1985)

To investigate whether infection with human T-cell lymphotropic virus/lymphadenopathy-associated virus (HTLV-III/LAV) may be persistent in asymptomatic persons and to correlate infection with seropositivity, we performed virologic and serologic studies in 25 of 30 persons who were identified as being at high risk for the acquired immunodeficiency syndrome (AIDS) and who had donated blood to patients who later contracted transfusion-associated AIDS. High-risk donors were those who belonged to a high-risk population, had AIDS or a closely related condition, or had a low ratio of helper to suppressor T lymphocytes. We performed similar studies in 6 of the 24 patients with AIDS who had received donations from this group. HTLV-III/LAV was isolated from 22 of the 25 donors, between 12 and 52 months (mean, 28) after they had donated blood, and from all 6 recipients, between 14 and 37 months (mean, 26) after they had received blood. Of the 22 virus-positive donors, 2 have contracted AIDS, 5 have generalized lymphadenopathy, and 15 (68 per cent) remain asymptomatic. Antibodies to HTLV-III/LAV were detectable by the enzyme-linked immunosorbent assay in serum samples obtained from each person at the time the virus was isolated. We conclude that infection with HTLV-III/LAV may be persistent and asymptomatic for years. This demonstration that viremic patients may be asymptomatic supports the use of serologic screening of donated blood to supplement current procedures for the prevention of transfusion-associated AIDS.
Expanding Purpura in a Neutropenic Patient
Authors: Zoe O. Brown-Joel, Nahid Y. Vidal, Karolyn A. Wanat
Journal: JAMA Oncology (2017)

A man in his 40s with newly diagnosed acute myelogenous leukemia arising from myelodysplasia presented with fever, cough, abdominal pain, difficulty swallowing, and 1 month of neutropenia. What is your diagnosis?
Endocannabinoids increase matrix metalloproteinase-9 in human bronchial epithelial cells via cannabinoid receptor signaling and p42/p44 MAP kinase
Authors: Saswati Hazra, Li Zhu, Katherine Peebles, Ming Liu, David Elashoff, Donald Tashkin, Jerry Shay, John Minna, Steven Dubinett, Brian Gardner
Journal: Cancer Research (2008)

AACR Annual Meeting-- Apr 12-16, 2008; San Diego, CA

1141 

Background: Non-small cell lung cancer (NSCLC) cells often elevate endocannabinoid production. To assess the role of endocannabinoids on lung epithelium and the pathogenesis of NSCLC, we utilize an in vitro model. In a non-transformed human bronchial epithelial cell (HBEC) line, cannabinoids concomitantly induce matrix metalloproteinase-9 (MMP9), cyclooxygenase-2 (COX-2) and its enzymatic product, prostaglandin E2 (PGE2). In lung cancer models, PGE2 has been linked to enhanced secretion of matrix metalloproteinase enzymes, which promote tumor invasion and metastasis by degrading the extracellular matrix. Additionally, in others systems, signaling through p42/p44 MAPK can elevate MMP9 secretion. Here we report the relative contribution of cannabinoid receptors, CB1 and CB2, PGE2, and p42/p44 MAPK in MMP9 induction by cannabinoids in HBECs.    Methods: HBEC cells were cultured in serum free media and treated with one of three cannabinoids (anandamide, 2-AG, or methanadamide) for 24 h. Culture supernatants were collected for PGE2 and MMP9 determination. Anandamide treated cell lysates were collected for western and RT-PCR analysis. Zymograms were performed with the culture media for MMP9 activity assay. To determine the role of CB1 and CB2 cannabinoid receptors in MMP9 induction, HBEC cells were incubated with the CB1 antagonist, SR141716, or the CB2 antagonist, SR144528, for 1 hr before addition of anandamide. The COX2 inhibitor, SC52836, was employed to evaluate the role of increased COX2/PGE2 in anandamide-mediated MMP9 production.    Results: All tested cannabinoids, anandamide, 2-AG, and methanandamide, increased PGE2 production to varying degrees, however only anandamide and methanadamide enhanced MMP9 secretion. Furthermore, pharmacologic inhibition of COX2 had no effect on MMP9 secretion in HBECs exposed to anandamide. Real time PCR indicates that anandamide up-regulates the CB2 receptor in HBECs, and CB1 and CB2 receptor antagonists prevent MMP9 induction by anandamide. Anandamide treatment triggers activation of Erk phosphorylation in HBEC cells. In addition, the p42/44 inhibitor, PD98059, abrogates anandamide-mediated induction of MMP9.    Conclusions: While, certain endocannabinoids concomitantly increase PGE2 and MMP9 production, and PGE2 has been linked to MMP9 expression in other models, our results demonstrate that PGE2 is not responsible for increased in MMP9 secretion in HBECs exposed to anandamide. Instead, anandamide elevates MMP9 through cannabinoid receptors, via p42/p44 MAPK. Our results indicate that MMP9 and COX-2 may be independently regulated in lung epithelial cells. This information may be useful for designing novel strategies for combined therapy or prevention of NSCLC.
Single Agent and Combinatorial Efficacy of First-in-Class Small Molecule ONC201 in Acute Leukemia and Multiple Myeloma
Authors: Varun V Prabhu, Amriti Lulla, Christina L Kline, Peter J Van den Heuvel, Mala K. Talekar, Jessica M Wagner, Rohinton S Tarapore, David T Dicker, Mathew J Garnett, Ultan McDermott, Cyril H Benes, Jeffrey J. Pu, David F. Claxton, Wolfgang Oster, Joshua E Allen, Wafik S. El-Deiry
Journal: Blood (2016)
Hematopoietic origin of Langerhans cell histiocytosis and Erdheim-Chester disease in adults
Authors: Paul Milne, Venetia Bigley, Chris M. Bacon, Antoine Néel, Naomi McGovern, Simon Bomken, Muzlifah Haniffa, Eli L. Diamond, Benjamin H. Durham, Johannes Visser, David Hunt, Harsha Gunawardena, Mac Macheta, Kenneth L. McClain, Carl Allen, Omar Abdel-Wahab, Matthew Collin
Journal: Blood (2017)
The Treatable Epilepsies
Authors: Antonio V. Delgado-Escueta, David M. Treiman, Gregory O. Walsh
Journal: New England Journal of Medicine (1983)

Antiepileptic Drug TreatmentThe Start of TherapyAntiepileptic drug treatment is obligatory when a diagnosis of generalized or partial epilepsy has been made.31 The aim is to control epileptic seizures in the absence of systemic or neurologic toxicity. Treatment should be started with one antiepileptic agent, preferably a first-choice drug. Table 3 summarizes some of the pharmacologic properties of the antiepileptic drugs most commonly used as single agents (monotherapy). The practitioner should try to achieve plasma concentrations that are known to stop seizures (the therapeutic range). In general, because plasma clearance is initially lower in "naive" patients — i.e., those who have . . .
A First in HCV Drugs for Youths
Authors: Rebecca Voelker
Journal: JAMA (2017)

Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
A Novel Regimen for Acute Myeloid Leukemia with MLL Partial Tandem Duplication: Results of a Phase 1 Study NCI 8485
Authors: Alice S. Mims, Rebecca B Klisovic, Ramiro Garzon, Alison R. Walker, Steven M. Devine, Katherine J. Walsh, Sumithira Vasu, Susan P. Whitman, Guido Marcucci, Nyla A. Heerema, Michael A. Caligiuri, Clara D. Bloomfield, John C. Byrd, Richard Piekarz, Michael R. Grever, William Blum
Journal: Blood (2016)
Studies on the relationship between the catecholamine distribution in the atrium and the specific granules present in atrial muscle cells: 2. Studies on the sedimentation pattern of atrial noradrenaline and adrenaline
Authors: A. J. D. BOLD, S. A. BENCOSME
Journal: Cardiovascular Research (1973)

Studies on the function of the specific granules present in mammalian atrial muscle cells have been directed mostly to the possible role of these particles as a storage site for catecholamines, particularly noradrenaline. The availability of a fractionation method previously described, which allows us to obtain a purified specific granule preparation, has made it possible to compare the pattern of sedimentation of atrial noradrenaline and adrenaline with that of the specific granules. It was found that, after fractionation, most of the atrial noradrenaline and adrenaline liberated during homogenization was present in the microsomal fraction and in the high speed supernatant. The crude specific granule fraction and the purified specific granule subfraction contained comparatively small amounts of noradrenaline. These findings do not support the view that the specific granules are a site of storage of noradrenaline.
Pathogenesis of Graves' Ophthalmopathy
Authors: Franklin H. Epstein, Rebecca S. Bahn, Armin E. Heufelder
Journal: New England Journal of Medicine (1993)

Ophthalmopathy is a potentially disfiguring and sight-threatening component of Graves' disease. It is clinically evident in 25 to 50 percent of patients with Graves' hyperthyroidism and occurs occasionally in patients with Hashimoto's thyroiditis and in those with Graves' disease but no evident thyroid disease1. At present, ophthalmopathy is not preventable, and treatment options for established, symptomatic disease are limited. To develop new strategies for the treatment and prevention of Graves' ophthalmopathy, a better understanding of its pathogenesis is necessary. In this paper we review studies aimed at identifying the pathogenic mechanisms that lead to Graves' ophthalmopathy.Clinical FeaturesPatients . . .
Abnormal Intracellular Modulation of Calcium as a Major Cause of Cardiac Contractile Dysfunction
Authors: J P Morgan
Journal: New England Journal of Medicine (1991)

THE release and reuptake of intracellular calcium are necessary to the normal systolic and diastolic function of the mammalian heart. The central part played by calcium ions in regulating excitation–contraction coupling and cycles of contraction and relaxation in the heart is diagrammed in Figure 1.1 , 2 There are two major calcium-dependent mechanisms that alter the contractile state of the heart: changing the availability of calcium to the myofilaments, and changing the responsiveness of the myofilaments to activation by intracellular calcium. The availability of intracellular calcium is regulated by the sarcolemma and sarcoplasmic reticulum, and calcium responsiveness is controlled by the myofilaments and . . .
Association between Drug-Metabolizing Enzymes Polymorphisms and Diffuse Large B-Cell Lymphoma Risk in the Middle Eastern Population.
Authors: Abdul K. Siraj, Rong Bu, Maha Al-Rasheed, Muna Ibrahim, Prashant Bavi, Jehad Abubaker, Naif Al-Jomah, Walid Mourad, Fouad Al-Dayel, Adnan Ezzat, Hassan El-Solh, Shahab Uddin, Khawla Al-Kuraya
Journal: Blood (2006)
Irritable Bowel Syndrome
Authors: Yehuda Ringel, Ami D. Sperber, Douglas A. Drossman
Journal: Annual Review of Medicine (2001)

▪ Abstract The irritable bowel syndrome (IBS) is a functional gastrointestinal disorder whose hallmark is abdominal pain or discomfort associated with a change in the consistency or frequency of stools. In the western world, 8% to 23% of adults have IBS and its socioeconomic cost is substantial. Research-generated insights have led to the understanding of IBS as a disorder of brain-gut regulation. The experience of symptoms derives from dysregulation of the bidirectional communication system between the gastrointestinal tract and the brain, mediated by neuroendocrine and immunological factors and modulated by psychosocial factors. The biopsychosocial model integrates the various physical and psychosocial factors that contribute to the patient's illness. This model and the recently revised symptom-based criteria (i.e. the “Rome II criteria”) form the basis for establishing a comprehensive and effective approach for the diagnosis and management of the disorder.
Leg Braces, Bronzed, in a Dusty Box
Authors: Brenda Butka
Journal: Annals of Internal Medicine (2017)

Ad Libitum16 May 2017Leg Braces, Bronzed, in a Dusty BoxBrenda Butka, MDBrenda Butka, MDFrom Nashville, Tennessee.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M17-0256 Audio Reading - “Leg Braces, Bronzed, in a Dusty Box” Audio. Michael A. LaCombe, MD, Annals Associate Editor, reads "Leg Braces, Bronzed, in a Dusty Box," by B. Butka. Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail there is a smell she remembersthe white coats, the stiff dresses,the cheers, the smiles, remembers somethingnot quite what, her mother was thereher mother was finally theregreen, the room had green shiny wallsshe's turned away from that greenall her lifeshe remembers how bright the lights werethe man kneeling in front of heradjusting the straps, the bucklesshe remembers she wore sockspink socks, everyone was watchingshe remembers feeling like she was going to falllike someone should be there to catch herpushed her wheeled chair outside... Author, Article, and Disclosure InformationAffiliations: From Nashville, Tennessee.Current Author Address: Brenda Butka, MD; e-mail, brenda.[email protected]edu. PreviousarticleNextarticle Advertisement Audio Reading - “Leg Braces, Bronzed, in a Dusty Box” Audio. Michael A. LaCombe, MD, Annals Associate Editor, reads "Leg Braces, Bronzed, in a Dusty Box," by B. Butka. Your browser does not support the audio element. Audio player progress bar Step backward in current audio track Play current audio trackPause current audio track Step forward in current audio track Mute current audio trackUnmute current audio track 00:00/ FiguresReferencesRelatedDetails Metrics 16 May 2017Volume 166, Issue 10Page: 757KeywordsEmotionsFallsSmellWheelchairs ePublished: 16 May 2017 Issue Published: 16 May 2017 Copyright & PermissionsCopyright © 2017 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...
Comparison of anti-cytochrome reactivity in autoimmune hepatitis of autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy and autoimmune hepatitis type 2.
Authors: U C Sharma, Dimitrios Bogdanos, Yun Ma, S Tanner, P McClean, R Williams, Giorgina Mieli-Vergani, Diego Vergani
Journal: Hepatology (2001)
Angiotensin-converting enzyme enhances the oxidative response and bactericidal activity of neutrophils
Authors: Zakir Khan, Xiao Z. Shen, Ellen A. Bernstein, Jorge F. Giani, Masahiro Eriguchi, Tuantuan V. Zhao, Romer A. Gonzalez-Villalobos, Sebastien Fuchs, George Y. Liu, Kenneth E. Bernstein
Journal: Blood (2017)
Final Results of a Phase 1/2 Open-Label Study to Assess the Safety, Tolerability and Preliminary Efficacy of Evofosfamide, a Hypoxia-Activated Prodrug, and Dexamethasone with or without Bortezomib in Subjects with Relapsed/Refractory Multiple Myeloma
Authors: Jacob P. Laubach, Noopur Raje, Andrew J. Yee, Philippe Armand, Robert L. Schlossman, Jacalyn Rosenblatt, Michael G. Martin, Craig Reynolds, Kenneth H. Shain, Ira Zackon, Laura V. Stampleman, Emily Lai, Aaron M. Caola, Joseph M. Cappuccio, Bradley Rivotto, Kaitlen Reyes, Alexandra Savell, Patrick Henrick, Tillman Pearce, Damian Handisides, Stew Kroll, Kenneth C. Anderson, Paul G. Richardson, Irene M. Ghobrial
Journal: Blood (2016)
STUDIES ON HOST-VIRUS INTERACTIONS IN THE CHICK EMBRYO-INFLUENZA VIRUS SYSTEM
Authors: Oscar C. Liu, Werner Henle
Journal: The Journal of Experimental Medicine (1951)

The combined passage of influenza A and B viruses in series, as reported by Sugg and Magill, has been confirmed. When the mixed passage materials were not too highly diluted both agents could be traced through 10 transfers. Growth curve experiments revealed that both agents developed independently, as measured by hemagglutination-inhibition tests in the presence of specific immune sera against one or the other type. However, the hemagglutinin titers of the 2 viruses in the mixed series were always substantially lower than those recorded when the strains were used individually as seed in the same concentrations as were employed in the mixed series. Assay of the infectivity titers of the individual strains in the presence of appropriate immune sera led to the demonstration that the time required for the growth cycle of influenza B virus varied with the dose of seed virus. With undiluted infected allantoic fluid as seed only 4 to 5 hours elapsed before new generations of virus were liberated. With increasing 10-fold dilution of the seed the constant period became increasingly longer until it stabilized at 8 to 10 hours. This finding offers an explanation for the seeming discrepancy between the observations on interference between the 2 viruses and the difference reported previously in the extent of their growth periods, on the one hand, and the fact that the 2 agents could be carried simultaneously in series through numerous passages in the chick embryo.