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21.
A custom-made thermoplastic splint was developed for the protection of the upper extremity after experimental surgery. It was used in 39 cases for a duration of 12-79 days. Complications were minimal and transient. The cast was easy to make, in one piece and inexpensive. Frequent removal for wound inspection was simple. This splint provides a good immobilization and protection of the arm and hand in the nonhuman primate. 相似文献
22.
J G Wilson D T Fearon R L Stevens N Seno K F Austen 《Journal of immunology (Baltimore, Md. : 1950)》1984,132(6):3058-3063
We compared the relative capacities of two over-sulfated glycosaminoglycans, heparin and chondroitin sulfate E, to alter the function of native properdin (nP) and activated properdin (aP) in the formation and stabilization of the amplification C3 convertase (C3b,Bb). Heparin was more active on a weight basis than chondroitin sulfate E in inhibiting the formation of C3b,Bb without or with nP, but had no influence on the decay of a pre-formed convertase, either unstabilized or stabilized with nP or aP. In contrast, chondroitin sulfate E was over 10-fold more active than heparin in preventing the formation of C3b,Bb in the presence of aP, and gave dose-related acceleration of decay of pre-formed C3b,Bb,aP but not of unstabilized or nP-stabilized pre-formed convertase. The inhibitory effect of both glycosaminoglycans on the formation of C3b,Bb in the presence of nP or aP was less when the number of C3b sites per target cell was increased. The preferential action of chondroitin sulfate E on the function of aP during the formation and decay of C3b,Bb,aP as compared to C3b,Bb,nP implies functional differences in the two forms of P even when they have been incorporated into C3b,Bb. The equal potency, when adjusted for uronic acid content, of chondroitin sulfate E proteoglycan isolated from the T cell-dependent, bone marrow-derived murine mast cell and of chondroitin sulfate E glycosaminoglycan from squid reveals that the linkage of the glycosaminoglycan to a peptide core does not diminish its regulatory action on the alternative complement pathway. 相似文献
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A group of captive chimpanzees, consisting of one adult male and three mother/infant pairs, was systematically observed over a 15-month period. Over 200 hr of data were collected, using both sequential and time sampling techniques, and compared to the available data on wild chimps. Unlike many captive groups, most behavior patterns were remarkably similar, both qualitatively and quantitatively, to that of wild chimpanzees including: play, grooming, infant sexual development, tool use, food sharing, prosocial partner preferences, and aggressive displays. 相似文献
25.
F J Stevens F A Westholm N Panagiotopoulos M Schiffer R A Popp A Solomon 《Journal of molecular biology》1981,147(1):185-193
A “naturally occurring” human κI VL dimer, designated Wat, has been isolated and crystallized. Protein Wat consists of two non-covalently bound monomers, each having a molecular weight of ~ 11,500. The monomer subunit is composed of an entire variable region light chain (VL) domain closely homologous to that of the κI Bence Jones protein Roy (Hilschmann &; Craig, 1965) as evidenced from amino acid composition, tryptic peptide map, and sequence analysis. Immunochemical studies substantiated that protein Wat is of the κ chain subgroup κI and lacks the isotypic and allotypic antigenic determinants associated with the κ constant region light chain domain. Two types of crystals of VL dimer Wat were obtained from ammonium sulfate or polyethylene glycol solutions. The type I crystals have unit cell dimensions of , and the space group is hexagonal P62 or P64. The asymmetric unit consists of one VL dimer; the fractional volume of unit cell occupied by solvent is 0.51. The unit cell dimensions of the type II crystals are ; the space group is hexagonal P6122 or P6522. Three variable domains constitute the asymmetric unit of the type II crystals; the fractional value of the solvent (0.52) is compatible with the value obtained for the type I crystals. 相似文献
26.
A numerical taxonomic study of strains of Actinobacillus, Pasteurella and Yersinia, with some allied bacteria, showed 23 reasonably distinct groups. These fell into three major areas. Area A contained species of Actinobacillus and Pasteurella: A. suis, A. equuli, A. lignieresii, P. haemolytica biovar A, P. haemolytica biovar T, P. multocida, A. actinomycetemcomitans, 'P. bettii', 'A. seminis', P. ureae and P. aerogenes. Also included in A was a composite group of Pasteurella pneumotropica and P. gallinarum, together with unnamed groups referred to as 'BLG', 'Mair', 'Ross' and 'aer-2'. Area B contained species of Yersinia: Y. enterocolitica, Y. pseudotuberculosis, Y. pestis and a group 'ent-b' similar to Y. enterocolitica. Area C contained non-fermenting strains: Y. philomiragia, Moraxella anatipestifer and a miscellaneous group 'past-b'. There were also a small number of unnamed single strains. 相似文献
27.
Elizabeth Franke Stevens 《Zoo biology》1991,10(1):53-63
Group displays in flamingos have been presumed to play a role in stimulating synchronous nesting and in facilitating pair formation. This study compares the group displays and breeding success of a captive flock of Caribbean flamingos (Phoenicopterus ruber ruber) at the National Zoological Park between 2 years: the frequency and synchrony of group displays were measured for a flock of 17 in 1988 and then again in 1989 after flock size was increased to 21. In 1989 the rate of occurrence of display activity increased 48%, the synchrony of group displays increased 100%, the frequency of mounts and copulations almost doubled, and for the first time in the flock's history two fertile eggs were produced. The use of sprinklers to simulate rain had no effect on the group displays. The amount of naturally occurring rainfall in 1989 was almost twice that in 1988. The increased frequency and synchrony of group displays could be attributed to increased flock size, change in sex ratio, addition of strange individuals, or increased rainfall. This study, however, provides evidence for a relationship between behavioral stimulation from group displays and components of breeding success in flamingos. 相似文献
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