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91.
92.
Carol M. Warner Ruth M. Graves Carla M. Tollefson Mary Jo F. Schmerr Thomas J. Stephens Carmen F. Merryman Paul H. Maurer 《Immunogenetics》1976,3(1):337-348
The immune response of allophenic mice of type C57BL/6(A × SJL) F1 to GL administered in complete Freund's adjuvant was tested. Control mice of the three strains C57BL/6, A, and SJL are all nonresponders to this antigen. However, the F1 generations of C57BL/6 × A, C57BL/6 × SJL, and A × SJL were all responders to the antigen, so that the complementarity of at least two genes is confirmed. The allophenic mice showed no further complementation beyond the F1 generation, a result which may argue against the possibility that more than two genes control the response to GL in these mouse strains. Characterization of the allophenic mice over several months showed that they exhibit chimeric drift, both in their coat color and in peripheral white blood cell population. There is no apparent correlation of coat color to the lymphocyte composition of the mice at any one time. The mice are true chimeras, since killing of the two populations of white blood cells with two different anti-H-2 sera produced a 100 percent killing. The immune response of individual allophenic mice to GL showed a good correlation to the number of A × SJL lympho-cytes in the animal.Abbreviations used in this paper are GL
an amino acid polymer of 57 %l-glutamic acid, 38%l-lysine, and 5%l-phenylalanine
- GLT15
an amino acid polymer ofl-glutamic acid,l-lysine, and 15 %l-tyrosine
- (T,G)-A-L
an amino acid polymer having a polylysine backbone with side chains of polyd-l-alanine, terminating in short sequences of tyrosine and glutamic acid
- GAT10
an amino acid polymer of 60%l-glutamic acid, 30%l-alanine, and 10%l-tyrosine
- GLA5
an amino acid polymer of 57%l-glutamic acid, 38%l-lysine, and 5%l-alanine
- DNP
2,4 dinitrophenyl
- BGG
bovine gamma globulin
- FCS
fetal calf serum
- PWBC
peripheral white blood cell
- SWBC
spleen white blood cell
- T cell
thymus-derived lymphocyte
- B cell
bone marrow-derived lymphocyte 相似文献
93.
Hilary O. Box 《Primates; journal of primatology》1975,16(2):155-174
Quantitative data were collected on the behaviour of four social groupings of captive common marmost monkeys. The observational study covered a period of eight months in 1973 during which time, data were intermittently collected on marking, self and social grooming, three categories of social play, together with some few additional data on close physical proximity and social contact referred to as ‘huddling.’ Each social group was observed for a total of 180-ten-min. observation sessions; one family group of monkeys was further observed individually for 100-ten-min. sessions. 相似文献
94.
95.
Polymerase chain reaction amplification products separated on rehydratable polyacrylamide gels and stained with silver 总被引:16,自引:0,他引:16
Separation of polymerase chain reaction (PCR) amplification of specific fragment length polymorphisms was carried out on rehydratable polyacrylamide gels on a horizontal flat slab system. A discontinuous sulfate-borate buffer system was employed on 5-8% T gels crosslinked with 3.5% C. Samples were diluted in leading sulfate ion buffer at 1/10 the ionic strength of the separating gel buffer and placed directly onto the surface of the rehydrated gels in 0.5-10 microliters volumes. The trailing ion and counterion were contained in a gel plug and placed directly onto the anodal and cathodal ends of the gel, and the electrodes placed directly onto the surface of the gel plugs. Filter paper wicks, soaked in diluted leading ion buffer, were placed along each side to lower the ionic strength of the edges, thereby increasing mobility at the edge and thus preventing smile effects. The gel-gel contact of the plug and separating gel prevent the production of a junction potential which occurs between dissimilar materials such as a paper wick and the gel. Ten- to 20-cm separations were carried out from 2-5 h, respectively, and resolution in the 20 cm system was 1.6-4 bp (base pairs) between 100 and 500 bp, 4-7 bp between 500 and 1000 bp, 12-20 bp between 1000 and 2000 bp and about 50 bp between 2000 and 3000 bp. Between 3000 and 4000 bp, resolution fell off to +/- 100 bp. Sensitivity, using a silver stain, indicated that one could readily distinguish less than 10 pg of DNA per mm width on the gels.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
96.
Food supplements placed daily beside the nests of herring gulls, Larus argentatus, for the first 5 days after the first chick hatched produced improved weight gains over this initial period and higher fledging success, particularly in the third chick. The fledging success of the fed group appears to be due to increased weight gain and not to increased parental protection in the supplemented period. Since there is indirect evidence that food is available this suggests that the parents are putting less effort into foraging for their chicks than they are able to, and less than is in the interests of the third chick, in the first days after hatching. On a separate colony we found that having three chicks in the brood for more than 5 days resulted in lower weight gains for the second chick, but not the first. We suggest that fledging three chicks rather than one or two greatly increases the parents' reproductive effort, and consequently interpret the third egg as primarily insurance against the loss of the first or second. 相似文献
97.
98.
With the goal of understanding how nervous systems produce activity and respond to the environment, neuroscientists turn to model systems that exhibit the activity of interest and are accessible and amenable to experimental methods. The stomatogastric nervous system (STNS) of the American lobster (Homarus americanus; also know was the Atlantic or Maine lobster) has been established as a model system for studying rhythm generating networks and neuromodulation of networks. The STNS consists of 3 anterior ganglia (2 commissural ganglia and an oesophageal ganglion), containing modulatory neurons that project centrally to the stomatogastric ganglion (STG). The STG contains approximately 30 neurons that comprise two central pattern generating networks, the pyloric and gastric networks that underlie feeding behaviors in crustaceans1,2. While it is possible to study this system in vivo3, the STNS continues to produce its rhythmic activity when isolated in vitro. Physical isolation of the STNS in a dish allows for easy access to the somata in the ganglia for intracellular electrophysiological recordings and to the nerves of the STNS for extracellular recordings. Isolating the STNS is a two-part process. The first part, dissecting the stomach from the animal, is described in an accompanying video article4. In this video article, fine dissection techniques are used to isolate the STNS from the stomach. This procedure results in a nervous system preparation that is available for electrophysiological recordings. 相似文献
99.
Genevieve E. Davis Mark F. Baumgartner Peter J. Corkeron Joel Bell Catherine Berchok Julianne M. Bonnell Jacqueline Bort Thornton Solange Brault Gary A. Buchanan Danielle M. Cholewiak Christopher W. Clark Julien Delarue Leila T. Hatch Holger Klinck Scott D. Kraus Bruce Martin David K. Mellinger Hilary Moors‐Murphy Sharon Nieukirk Douglas P. Nowacek Susan E. Parks Dawn Parry Nicole Pegg Andrew J. Read Aaron N. Rice Denise Risch Alyssa Scott Melissa S. Soldevilla Kathleen M. Stafford Joy E. Stanistreet Erin Summers Sean Todd Sofie M. Van Parijs 《Global Change Biology》2020,26(9):4812-4840
Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate‐driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke (Balaenoptera acutorostrata) and North Atlantic right whales (NARW; Eubalaena glacialis). This study assesses the acoustic presence of humpback (Megaptera novaeangliae), sei (B. borealis), fin (B. physalus), and blue whales (B. musculus) over a decade, based on daily detections of their vocalizations. Data collected from 2004 to 2014 on 281 bottom‐mounted recorders, totaling 35,033 days, were processed using automated detection software and screened for each species' presence. A published study on NARW acoustics revealed significant changes in occurrence patterns between the periods of 2004–2010 and 2011–2014; therefore, these same time periods were examined here. All four species were present from the Southeast United States to Greenland; humpback whales were also present in the Caribbean. All species occurred throughout all regions in the winter, suggesting that baleen whales are widely distributed during these months. Each of the species showed significant changes in acoustic occurrence after 2010. Similar to NARWs, sei whales had higher acoustic occurrence in mid‐Atlantic regions after 2010. Fin, blue, and sei whales were more frequently detected in the northern latitudes of the study area after 2010. Despite this general northward shift, all four species were detected less on the Scotian Shelf area after 2010, matching documented shifts in prey availability in this region. A decade of acoustic observations have shown important distributional changes over the range of baleen whales, mirroring known climatic shifts and identifying new habitats that will require further protection from anthropogenic threats like fixed fishing gear, shipping, and noise pollution. 相似文献
100.