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71.
72.
M. Nakai Kiyotaka Toshimori Kazuya Yoshinaga Tetsuo Nasu Rex A. Hess 《Cell and tissue research》1998,294(1):145-152
Effects of a single, high dose of orally administered carbendazim (100 mg/kg) on acrosome formation in the early phases of
spermiogenesis were examined by electron microscopy and immunocytochemistry up to day 7.5 post-treatment. No obvious abnormality
of acrosome development was noted in the Golgi phase spermatids on day 1.5 post-treatment. On day 3, step 1 spermatids were
seen in stage III seminiferous tubules. In stage V tubules at this post-treatment interval, direct connections between the
trans-side saccules of the Golgi stacks and the outer acrosomic membranes were observed in step 5 spermatids. Similar direct
connections between these two organelles were also observed in the advanced round spermatids in later stages at days 4.5 and
7.5. On day 4.5, step 1 and 3 spermatids were seen in stage V tubules. On day 7.5, round spermatids with various abnormalities
of acrosome development were observed in stage VII tubules, in addition to the discontinuous and granular acrosomes reported
previously. These features were not observed in testes of control animals. In the immunocytochemical analysis using an antibody
mMN7 that recognizes a protein delivered from the Golgi apparatus to the acrosome, spermatids exposed to carbendazim showed
various abnormal immunostaining patterns in the acrosomes. On the other hand, strong immunoreactivity was observed in the
Golgi saccules connecting to the acrosomes. These results suggest that in testis treated with carbendazim acrosome development
is impaired during the early phases of spermiogenesis, and material supply from the Golgi apparatus to the acrosome is perturbed,
which is a possible cause of the abnormal development.
Received: 31 March 1998 / Accepted: 28 May 1998 相似文献
73.
Jayaraman Selvaraj Veeraraghavan Vishnupriya Hussain Sardar Janardhana Papayya Balakrishna Josephine Rex Surapaneni Krishna Mohan Periyasamy Vijayalakshmi Rajagopal Ponnulakshmi 《Bioinformation》2020,16(11):801
Beta-catenin is linked with colorectal cancer (CRC). Therefore, it is of interest to design and develop novel compounds to combat CRC. Hence, we document compounds (chlorogenic acid, gallic acid, protocatechuic acid, quercetin and vanillic acid) from Lycopersicon esculentum with optimal binding features for further consideration. 相似文献
74.
Pritam Singh Graeme B. Russell Yuji Hayashi Rex T. Gallagher Susan Fredericksen 《Entomologia Experimentalis et Applicata》1979,25(2):121-127
The effects on housefly (Musca domestica) of six norditerpene lactones (nagilactones B, D, E, podolide, hallactone B and 14-epi-ponalactone A) in a defined diet were tested. Nagilactone D was the most active, with an LD50 of 0.7 ppm. Nagilactones C and D were also toxic to light-brown apple moth (Epiphyas postvittana) and codling moth (Laspeyresia pomonella).The relationship between lactone structure and toxicity to housefly is discussed.
Zusammenfassung Viele aus Podocarpus-Arten isolierte Norditerpenlactone sind für Stubenfliegen toxisch. Es wird über die Resultate der Fütterung von sechs Lactonen an die Stubenfliege in einem definierten Nährboden berichtet und die LD50 von zwölf Verbindungen werden verglichen. Der aktivste Stoff ist Nagilacton mit einer LD50 von 0,7 ppm. Nagilacton C und D sind auch toxisch für Epiphyas postvittana und für den Apfelwickler. Die wirksamsten Verbindungen haben eine kurze nichtpolare Seitenkette und eine elektronenreiche, funktionelle Gruppe bei C-8, ferner sind sie Epoxyalkohole in Ring-A. Diese in der Natur vorkommenden Lactone spielen wahrscheinlich eine Schutzrolle in der Pflanze.相似文献
75.
Kimberly B. Fortner Chad A. Grotegut Carla E. Ransom Rex C. Bentley Liping Feng Lan Lan R. Phillips Heine Patrick C. Seed Amy P. Murtha 《PloS one》2014,9(1)
Objective
Bacterial colonization of the fetal membranes and its role in pathogenesis of membrane rupture is poorly understood. Prior retrospective work revealed chorion layer thinning in preterm premature rupture of membranes (PPROM) subjects. Our objective was to prospectively examine fetal membrane chorion thinning and to correlate to bacterial presence in PPROM, preterm, and term subjects.Study Design
Paired membrane samples (membrane rupture and membrane distant) were prospectively collected from: PPROM = 14, preterm labor (PTL = 8), preterm no labor (PTNL = 8), term labor (TL = 10), and term no labor (TNL = 8), subjects. Sections were probed with cytokeratin to identify fetal trophoblast layer of the chorion using immunohistochemistry. Fluorescence in situ hybridization was performed using broad range 16 s ribosomal RNA probe. Images were evaluated, chorion and choriodecidua were measured, and bacterial fluorescence scored. Chorion thinning and bacterial presence were compared among and between groups using Student''s t-test, linear mixed effect model, and Poisson regression model (SAS Cary, NC).Results
In all groups, the fetal chorion cellular layer was thinner at rupture compared to distant site (147.2 vs. 253.7 µm, p<0.0001). Further, chorion thinning was greatest among PPROM subjects compared to all other groups combined, regardless of site sampled [PPROM(114.9) vs. PTL(246.0) vs. PTNL(200.8) vs. TL(217.9) vs. TNL(246.5)]. Bacteria counts were highest among PPROM subjects compared to all other groups regardless of site sampled or histologic infection [PPROM(31) vs. PTL(9) vs. PTNL(7) vs. TL(7) vs. TNL(6)]. Among all subjects at both sites, bacterial counts were inversely correlated with chorion thinning, even excluding histologic chorioamnionitis (p<0.0001 and p = 0.05).Conclusions
Fetal chorion was uniformly thinner at rupture site compared to distant sites. In PPROM fetal chorion, we demonstrated pronounced global thinning. Although cause or consequence is uncertain, bacterial presence is greatest and inversely correlated with chorion thinning among PPROM subjects. 相似文献76.
Rex L. Lowe 《Journal of phycology》1975,11(4):415-424
Cyclotella atomus Hust., C. meneghiniana Kütz., C. comta (Ehr.) Kütz., C. antiqua W. Sm., C. michiganiana Skv., C. ocellata Pant., C. glomerata Bachmann, C. pseudostelligera Hust., and C. stelligera (Cleve et Grun.) V. H., were selected for ultrastructure investigations on the basis of their ready availability. Specimens were examined employing both transmission and scanning electron microscopy. Strutted processes, labiate processes, spines and other special features were surveyed in all species. On the basis of these observations the species of Cyclotella observed seem to be in one of 3 morphological groups, the meneghiniana group, the comta group, and the stelligera group. 相似文献
77.
Correlation of enzymatic,metabolic, and behavioral deficits in thiamin deficiency and its reversal 总被引:5,自引:0,他引:5
Gary E. Gibson Hanna Ksiezak-Reding Kwan-Fu Rex Sheu Victoria Mykytyn John P. Blass 《Neurochemical research》1984,9(6):803-814
To clarify the enzymatic mechanisms of brain damage inthiamin deficiency, glucose oxidation, acetylcholine synthesis, and the activities of the three major thiamin pyrophosphate (TPP) dependent brain enzymes were compared in untreated controls, in symptomatic pyrithiamin-induced thiamin-deficient rats, and in animals in which the symptoms had been reversed by treatment with thiamin. Although brain slices from symptomatic animals produced14CO2 and14C-acetylcholine from [U-14C]glucose at rates similar to controls under resting conditions, their K+-induced-increase declined by 50 and 75%, respectively. In brain homogenates from these same animals, the activities of two TPP-dependent enzymes transketolase (EC 2.2.1.1) and 2-oxoglutarate dehydrogenase complex (EC 1.2.4.2, EC 2.3.1.61, EC 1.6.4.3) decreased 60–65% and 36%, respectively. The activity of the third TPP-dependent enzyme, pyruvate dehydrogenase complex (EC 1.2.4.1, EC 2.3.1.12, EC 1.6.4.3.) did not change nor did the activity of its activator pyruvate dehydrogenase phosphate phosphatase (EC 3.1.3.43). Although treatment with thiamin for seven days reversed the neurological symptoms and restored glucose oxidation, acetylcholine synthesis and 2-oxoglutarate dehydrogenase activity to normal, transketolase activity remained 30–32% lower than controls. The activities of other TPP-independent enzymes (hexokinase, phosphofructokinase, and glutamate dehydrogenase) were normal in both deficient and reversed animals.Thus, changes in the neurological signs during pyrithiamin-induced thiamin deficiency and in recovery paralleled the reversible damage to a mitochondrial enzyme and impairment of glucose oxidation and acetylcholine synthesis. A more sustained deficit in the pentose pathway enzyme, transketolase, may relate to the anatomical abnormalities that accompany thiamin deficiency.Dedicated to Henry McIlwain. 相似文献
78.
79.
Xing De Su Baofeng Li Shangjia Bangs Max Creamer David Coogan Michael Wang Jinhai Simora Rhoda Ma Xiaoli Hettiarachchi Darshika Alston Veronica Wang Wenwen Johnson Andrew Lu Cuiyu Hasin Tasnuba Qin Zhenkui Dunham Rex 《Marine biotechnology (New York, N.Y.)》2022,24(3):513-523
Marine Biotechnology - Omega-3 polyunsaturated fatty acids (n-3 PUFAs), particularly eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), play a very important role in... 相似文献
80.
Rex Duncan 《The Western journal of medicine》1922,20(9):291-294