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91.
A new procedure for mastopexy, with or wtihout an augmentatiom mammaplasty, is presented. Its advantage is the minimal resultant scarring in the least conspicuous location. 相似文献
92.
Anticoagulant low molecular weight heparin does not enhance the activation of plasminogen by tissue plasminogen activator 总被引:1,自引:0,他引:1
The activity of tissue plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA) is stimulated by heparin. Heparin binds tightly to t-PA, u-PA, and plasminogen and decreases the usual stimulatory effect of fibrin on t-PA activity. In the present study we have found that low molecular weight heparin (LMW-heparin) preparations obtained by nitrous acid depolymerization or heparinase treatment of standard heparin have different properties with respect to their interaction with the fibrinolytic system. LMW-heparin prepared by either method does not stimulate plasmin formation by t-PA. However, these preparations of heparin still efficiently accelerate the inhibition of thrombin by antithrombin III. Binding data show that LMW-heparin does not bind t-PA and Glu-plasminogen and only binds very weakly to Lys-plasminogen. These results illustrate that it is possible to selectively destroy the fibrinolytic stimulating properties of heparin while leaving the classical anticoagulant characteristics intact. 相似文献
93.
Sylvatic trichinosis in Ontario, Canada 总被引:2,自引:0,他引:2
Samples of muscle from 4,773 specimens of 18 species of wild mammals from Ontario were examined for Trichinella. One of 12 mink (Mustela vison), 83 of 1,821 fisher (Martes pennanti) and 68 of 1,980 marten (Martes americana) had T. spiralis. Prevalences of infections by Trichinella were determined for fisher and marten from the Algonquin region, over a 10-yr period. Prevalences ranged from 0.9-9.2% in fisher and 1.3-8.7% in marten indicating that the parasite is well-established in the region. Prevalences of Trichinella increased with age of both fisher and marten. Intensities determined for the 1981-1982 sample ranged from 0.4-15.8 larvae/g for fisher and 22.4-159.7 larvae/g for marten. Higher intensities were not correlated with older hosts. Fisher and marten appeared to be the key hosts maintaining Trichinella in the Algonquin region, but transmission dynamics were unclear. Transmission may include an unidentified small rodent or other host and natural carrion-feeding. 相似文献
94.
A technique is described for detecting fibrinolytic activity of single cells in culture. This method was applied to the analysis of rat ovarian granulosa cells. Cells obtained from follicules shortly before ovulation show high levels of fibrinolytic activity. This activity is plasminogen-dependent, indicating that it is due to plasminogen activator. The appearance of this activity is correlated with ovulation by temporal and functional criteria, and can be demonstrated both in immature animals primed with hormones and in mature cycling animals. Granulosa cell cultures can be stimulated to release plasminogen activator by exposure in vitro either to luteinizing hormone or to dibutyryl cyclic AMP. 相似文献
95.
Jordan L. Youngmann Randy W. Deyoung Stephen Demarais Bronson K. Strickland Gabe Jenkins 《The Journal of wildlife management》2020,84(3):515-523
Translocations are a common management practice to restore or augment populations. Understanding the genetic consequences of translocation efforts is important for the long-term health of restored populations. The restoration of elk (Cervus canadensis) to Kentucky, USA, included source stocks from 6 western states, which were released at 8 sites in southeastern Kentucky during 1997–2002. We assessed genetic diversity in restored herds and compared genetic similarity to source stocks based on 15 microsatellite DNA loci. Genetic variation in the restored populations was comparable to source stocks ( allelic richness = 3.52 and 3.50; expected heterozygosity = 0.665 and 0.661 for restored and source, respectively). Genetic differentiation among all source and restored populations ranged from 0.000 to 0.065 for pairwise FST and 0.034 to 0.161 for pairwise Nei's DA. Pairwise genetic differentiation and Bayesian clustering revealed that stocks from Utah and North Dakota, USA, contributed most to restored populations. Other western stocks appeared less successful and were not detected with our data, though our sampling was not exhaustive. We also inferred natural movements of elk among release sites by the presence of multiple genetic stocks. The success of the elk restoration effort in Kentucky may be due, in part, to the large number of elk (n = 1,548), repeated releases, and use of diverse source stocks. Future restoration efforts for elk in the eastern United States should consider the use of multiple stock sources and a large number of individuals. In addition, preservation of genetic samples of founder stock will enable detailed monitoring in the future. © 2020 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. 相似文献
96.
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98.
C G Kolvenbach K E Langley T W Strickland W C Kenney T Arakawa 《Journal of biochemical and biophysical methods》1991,23(4):295-300
Carbohydrates play important roles in activity, stability and pharmacokinetics of glycoproteins and the degree of glycosylation varies with proteins. In this communication, a simple method of determining the carbohydrate content was developed, which consists of measuring the density increments of a glycoprotein and its non-glycosylated counterpart, and then dividing the difference between the two values by the density increment of carbohydrates. The density increment was relatively constant for various sugars except for sialic acid, and hence assumed to be 0.39. Thus, we obtained carbohydrate contents of 38, 28, 8 and 7% for Chinese hamster ovary cell-expressed erythropoietin (EPO), stem cell factor (SCF), granulocyte-colony-stimulating factor (G-CSF), and platelet-derived growth factor (PDGF), respectively. These values are in close agreement with those determined by other methods. 相似文献
99.
Ranganathan S Liu CX Migliorini MM Von Arnim CA Peltan ID Mikhailenko I Hyman BT Strickland DK 《The Journal of biological chemistry》2004,279(39):40536-40544
The low density lipoprotein receptor-related protein (LRP) is a large receptor that participates in endocytosis, signaling pathways, and phagocytosis of necrotic cells. Mechanisms that direct LRP to function in these distinct pathways likely involve its association with distinct cytoplasmic adaptor proteins. We tested the hypothesis that the association of various adaptor proteins with the LRP cytoplasmic domain is modulated by its phosphorylation state. Phosphoamino acid analysis of metabolically labeled LRP revealed that this receptor is phosphorylated at serine, threonine, and tyrosine residues within its cytoplasmic domain, whereas inhibitor studies identified protein kinase Calpha (PKCalpha) as a kinase capable of phosphorylating LRP. Mutational analysis identified critical threonine and serine residues within the LRP cytoplasmic domain that are necessary for phosphorylation mediated by PKCalpha. Mutating these threonine and serine residues to alanines generated a receptor that was not phosphorylated and that was internalized more rapidly than wild-type LRP, revealing that phosphorylation reduces the association of LRP with adaptor molecules of the endocytic machinery. In contrast, serine and threonine phosphorylation was necessary for the interaction of LRP with Shc, an adaptor protein that participates in signaling events. Furthermore, serine and threonine phosphorylation increased the interaction of LRP with other adaptor proteins such as Dab-1 and CED-6/GULP. These results indicate that phosphorylation of LRP by PKCalpha modulates the endocytic and signaling function of LRP by modifying its association with adaptor proteins. 相似文献
100.
Purification and properties of a plasminogen activator from cultured rat prostate adenocarcinoma cells 总被引:1,自引:0,他引:1
Zymographic analysis of the supernates from confluent cultures of a rat prostate adenocarcinoma cell line, PA-III, revealed the existence of two molecular forms of specific plasminogen activators, one of molecular weight of approximately 80 000 and another of approximate molecular weight of 45 000, in sodium dodecyl sulfate. The low molecular weight form has been purified 364-fold in 66% yield from the culture medium by a combination of gel filtration on Sephacryl S-200 and affinity chromatography on Sepharose 4B-benzamidine. The purified material possessed a specific activity of 192 000 urokinase CTA units mg-1. This enzyme displayed activity toward human Glu1-plasminogen, characterized by a Km of 1.7 +/- 0.2 microM and a Vmax of 0.53 +/- 0.1 pmol of plasmin min-1 unit-1. A synthetic chromogenic substrate, H-D-Ile-Pro-Arg-p-nitroanilide (S-2288), was found for the activator. The enzyme possessed a Km of 0.33 mM and a kcat of 55 s-1 for S-2288. The activator was found to be a serine protease, inhibited by diisopropyl fluorophosphate (iPr2PF). At a concentration of 1 mM iPr2PF, and 30 nM enzyme, the half-time of this inhibition was 3.8 min. The 45 000 molecular weight enzyme was found to be inhibited by rabbit antibodies to human urokinase, thus characterizing the activator as a member of the urokinase class. The 80 000 molecular weight enzyme was not neutralized by anti-human urokinase but was neutralized by rabbit anti-human melanoma activator, likely allowing it to be classified as the tissue activator type. 相似文献