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1.
Effects of the fungal endophyte Acremonium coenophialum in fescue on pregnant mares and foal viability. 总被引:1,自引:0,他引:1
M R Putnam D I Bransby J Schumacher T R Boosinger L Bush R A Shelby J T Vaughan D Ball J P Brendemuehl 《American journal of veterinary research》1991,52(12):2071-2074
Effects of the endophyte Acremonium coenophialum in tall fescue on pregnant mares and foal viability were evaluated. Twenty-two mature pregnant mares were randomly chosen to graze either Kentucky-31 tall fescue that was free from A coenophialum (endophyte-free, EF) or tall fescue infected with A coenophialum (endophyte-present, EP) after the first 90 days of pregnancy through parturition. Concentrations of pyrrolizidine and ergopeptine alkaloids were significantly greater in EP grass, compared with EF pasture. Ten of 11 mares grazing EP pasture had obvious dystocia. Mean duration of gestation was significantly greater for the EP group, compared with the EF group. Foal survivability was severely reduced among mares grazing EP fescue with only 1 foal surviving the natal period. Udder development and lactation were low in mares grazing EP grass. The absence of clinical problems in mares grazing EF grass implicated the endophyte as the causative agent of reproductive problems and perinatal foal mortality in pregnant mares grazing endophyte-infected fescue grass. Caution should be exercised in allowing pregnant mares to graze pastures infected with the endophyte A coenophialum. 相似文献
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Macroglobulin structure: homology of mu and gamma heavy chains of human immunoglobulins 总被引:8,自引:0,他引:8
The amino acid sequence of fragments obtained by cyanogen bromide cleavage of the mu-chain of a human gammaM-globulin is homologous to the NH(2)-terminal sequences of the gamma-chain of human and rabbit gammaG-globulins and is related to that of human light chains. This supports the hypothesis that light and heavy chains evolved from a common ancestral gene. 相似文献
5.
Gamma globulins: structure and control of biosynthesis 总被引:2,自引:0,他引:2
F W Putnam 《Science (New York, N.Y.)》1967,158(802):813-814
6.
Analysis of the amino acid sequence of one Bence Jones protein is almost comtplete. Many points of interchange occur in the amino terminal. portion of the molecule relative to partial-sequence data for other proteins. Most, but not all, are, compartible with one-step mutations. Such structural variation in immunoglobulin light chains may result from many related genes. 相似文献
7.
Armbrust EV Berges JA Bowler C Green BR Martinez D Putnam NH Zhou S Allen AE Apt KE Bechner M Brzezinski MA Chaal BK Chiovitti A Davis AK Demarest MS Detter JC Glavina T Goodstein D Hadi MZ Hellsten U Hildebrand M Jenkins BD Jurka J Kapitonov VV Kröger N Lau WW Lane TW Larimer FW Lippmeier JC Lucas S Medina M Montsant A Obornik M Parker MS Palenik B Pazour GJ Richardson PM Rynearson TA Saito MA Schwartz DC Thamatrakoln K Valentin K Vardi A Wilkerson FP Rokhsar DS 《Science (New York, N.Y.)》2004,306(5693):79-86
Diatoms are unicellular algae with plastids acquired by secondary endosymbiosis. They are responsible for approximately 20% of global carbon fixation. We report the 34 million-base pair draft nuclear genome of the marine diatom Thalassiosira pseudonana and its 129 thousand-base pair plastid and 44 thousand-base pair mitochondrial genomes. Sequence and optical restriction mapping revealed 24 diploid nuclear chromosomes. We identified novel genes for silicic acid transport and formation of silica-based cell walls, high-affinity iron uptake, biosynthetic enzymes for several types of polyunsaturated fatty acids, use of a range of nitrogenous compounds, and a complete urea cycle, all attributes that allow diatoms to prosper in aquatic environments. 相似文献
8.
Emotion is normally regulated in the human brain by a complex circuit consisting of the orbital frontal cortex, amygdala, anterior cingulate cortex, and several other interconnected regions. There are both genetic and environmental contributions to the structure and function of this circuitry. We posit that impulsive aggression and violence arise as a consequence of faulty emotion regulation. Indeed, the prefrontal cortex receives a major serotonergic projection, which is dysfunctional in individuals who show impulsive violence. Individuals vulnerable to faulty regulation of negative emotion are at risk for violence and aggression. Research on the neural circuitry of emotion regulation suggests new avenues of intervention for such at-risk populations. 相似文献
9.
M R Putnam 《Veterinary Clinics of North America: Food Animal Practice》1989,5(2):325-344
Because a significant number of toxins affect food animal reproduction, the investigating clinician should be aware of their presence and action. If the clinician is confronted with infertility and abortions, the biotoxins, plant estrogens, nitrates, fescue, and selenium-accumulating plants should be considered. The region of the country will limit the considerations. Outbreaks of congenital defects should prompt the clinician to check for the presence and consumption of the teratogenic plants found in the region. Investigation of toxins affecting food animal reproduction always should be done in the total context of infectious and management causes. Proper understanding of suspected toxins is necessary for correct interpretation of toxins affecting reproduction. 相似文献
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