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1.
M. L. Dini J. O'Donnell S. R. Carpenter M. M. Elser J. J. Elser A. M. Bergquist 《Hydrobiologia》1987,150(2):185-191
The timing and magnitude of diel migration in two daphnid assemblages were determined from a series of vertical profiles of daphnid size distribution. Animals were collected concurrently for gut fullness determination. Only large daphnids (> 1.4 mm) migrated, but these animals could account for substantial vertical and diel differences in phosphorus excretion rate. Gut fullness measurements and time courses of diel vertical migration suggested that large Daphnia can cause a net downward flux of phosphorus during summer in thermally stratified lakes. 相似文献
2.
Successful pregnancy in a woman with congenital factor XIII deficiency treated with substitutive therapy. Report of a second case 总被引:1,自引:0,他引:1
A syndrome of marked fetal wastage is associated with congenital factor XIII deficiency in adult women. A previously unreported case of a woman with factor XIII deficiency is described, in which substitutive treatment with normal plasma or placental factor XIII concentrate permitted two normal pregnancies. Factor XIII activity was maintained above 1-2% with intermittent infusion of 300 ml to 450 ml of plasma every 14 days or of 500 units of concentrate every 21 days. This case confirms the only other case so far reported in which factor XIII substitutive therapy was able to permit a normal pregnancy in a woman with factor XIII deficiency and seems to suggest factor XIII to be involved in the process of annidation. 相似文献
3.
This report deals with the modulation of activity and expression of the hepatic asialoglycoprotein receptor, in pregnant or diethylstilbestrol-treated rats.The results show a two-fold increase in the total cell associated binding activity, both in pregnant and in estrogen-treated animals, with respect to normal values. On the contrary the surface expression was shown to be strongly enhanced only in the liver of pregnant rat. Therefore the modulation shown by this receptor system in pregnancy seems to be only partially estrogen-dependent. 相似文献
4.
David H. Sachs Chief Sharon Germana Mona El-Gamil Kenth Gustafsson Francois Hirsch Karen Pratt 《Immunogenetics》1988,28(1):22-29
Class II genes of miniature swine have been characterized by restriction fragment length polymorphism (RFLP) analysis and by analysis of a series of clones isolated from a lymphocyte genomic library. For RFLP analysis, DNA samples from three independent major histocompatibility complex homozygous lines and three intra-MHC recombinant lines were digested with a variety of restriction enzymes and analyzed in Southern blots using human cDNA probes for DP, DQ, DR, and DZ alpha genes, and DP, DQ, DR, and DO beta genes. One, or at most two, unique fragments were detected by hybridization with each of the human probes tested. In contrast, multiple bands (five to six for most enzymes examined) were detected by each of the human probes tested, the majority of which were found to cross-react with at least three of these probes under conditions of moderate stringency. Genomic DNA from the SLA
c
haplotype was cloned into an EMBL-3 bacteriophage vector, and the corresponding genomic library was screened with each of these human cDNA probes. The class II genes thereby isolated from this library showed characteristics consistent with those anticipated from the RFLP analysis. Thus, unique genes were obtained which showed no evidence of cross-hybridization, while genes showed extensive cross-hybridization and were frequently detected in the library by more than one human gene probe. These data are consistent with early evolutionary divergence of a genes, prior to mammalian speciation, and with continuing evolution of genes, with possible shared usage of these genes by different a loci. The data also imply that genes can readily be assigned to loci homologous to their human counterparts, but that genes will require further mapping and/or sequence analysis to confirm assignments. 相似文献
5.
A Dini L Rastrelli P Saturnino O Schettino 《Bollettino della Società italiana di biologia sperimentale》1991,67(12):1053-1058
This work deals with the isolation and characterization in Ullucus tuberosus of flavonoids, a class of natural products influencing potentially the taste and nutritional value of the plant food. The three flavonoids, rutin, narcissin and kaempferol 3-O-(2",6"-di-O-alpha-L-rhamnopyranosil)-beta-D-glucopyranoside, isolated, are devoid of taste, but appear to possess health promoting effects. 相似文献
6.
L Dini 《Cellular and molecular biology, including cyto-enzymology》1991,37(2):165-171
We examined the receptor-mediated endocytosis of asialoglycoproteins in thick sections of cultured hepatocytes of newborn rats by high voltage electron microscope. The organelles involved in endocytosis are revealed ultrastructurally using colloidal gold particles coupled to lactosylated bovine serum albumin. Keeping the cells at 4 degrees C the marker binds to the cell surface showing microvilli, and is not internalized. Increasing the temperature to 37 degrees C, we observed that within 5-15 min. the marker enters the intracellular endocytic organelles close to the cell surface. After 60 min. the marker is found in the larger and deeper endocytic organelles and in large lisosome-like vesicles. We find that the process of endocytosis in newborn cultured hepatocytes is similar to that found in cultured cells of adult rats, but the process of internalization is slower. 相似文献
7.
The Mr 17500 region of the A chain of urokinase is required for interaction with a specific receptor in A431 cells 总被引:6,自引:0,他引:6
We have found the existence of specific receptors for the plasminogen activator, urokinase, in A431 human epidermoid carcinoma cells, cultures in plasminogen-free conditions. Two subsets of receptors have been recognized on the basis of 125I-labelled urokinase binding analysis: about 1 X 10(3) high-affinity (Kd = 5.0 X 10(-11) M) and 1 X 10(5) low-affinity (Kd = 9 X 10(-9) M) receptors per cell. The electron microscopic observation of a urokinase: ferritin conjugate has shown single and clustered receptors at the cell surface. Down-regulation of the receptors (T1/2 = 3.77 h) follows the binding of urokinase. The binding does not involve an intact catalytic site and is inhibited by a monoclonal antibody against the Mr 17500 proteolytic fragment of the A chain of urokinase. 相似文献
8.
M T Parodi M Baffico G P Tonini G Dini G Ferrea L Massimo P Cornaglia-Ferraris 《International journal of cell cloning》1986,4(4):263-273
A long-term culture of bone marrow lymphoblasts in a case of unclassified acute lymphoblastic leukemia is described. Cells lacking any lymphocytic marker in the early phase of the culture were gradually substituted by B cells showing a pattern of polyclonality. The culture supernatant contained high levels of immunoglobulins also showing interleukin 2 activity. Search for antigens related to the Epstein-Barr virus was negative. A clonal expansion of B cells versus spontaneous differentiation of unclassified leukemic cells is discussed; the long-term culture technique as a tool for a better evaluation of leukemic cells is suggested and discussed. 相似文献
9.
10.
G Bruscalupi L Dini A Trentalance 《Cellular and molecular biology, including cyto-enzymology》1989,35(1):47-54
Compositional and maturative parameters of high density lipoproteins (HDL) have been examined during the early stages of rat liver regeneration, when lecithin:cholesterol acyltransferase (LCAT) activity, responsible for the maturation of this lipoprotein class, is markedly decreased. Both HDL subclass distribution and chemical composition are not significantly different from the control, except for a slightly lower cholesterol ester content. Few disc-shaped particles are detectable by electron microscopic observation. Cholesterol ester decrease and presence of immature particles are related, but the entity of the modification is lower than suggested by the deep decrease of LCAT activity. This seems to indicate that proper HDL maturation is assured in the regenerating liver despite low LCAT activity. 相似文献