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21.
Castleman's disease, plasma-cell type. Diagnosis of central nervous system involvement by cerebrospinal fluid cytology 总被引:1,自引:0,他引:1
A case of Castleman's disease of the plasma-cell type is reported in which central nervous system (CNS) involvement was diagnosed by cerebrospinal fluid (CSF) cytology. The patient had multicentric disease with constitutional symptoms, immunologic abnormalities and peripheral blood cytopenias requiring cytotoxic agents and steroids for treatment. CNS symptoms and diagnostic cytologic findings in CSF occurred in the absence of morphologic lesions demonstrable by computed tomography or magnetic resonance imaging of the brain. 相似文献
22.
G N Gaulton A H Sharpe D W Chang B N Fields M I Greene 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(9):2930-2936
A syngeneic monoclonal anti-idiotope that behaves as an internal image of the mammalian reovirus type 3 cellular attachment protein (viral hemagglutinin) was used in the syngeneic host for the induction of a prophylactic anti-viral antibody response. These studies were performed without the aid of co-stimulation by viral antigens. The high stringency of this system enables us to define the maximum constraints on the use of anti-idiotopes as anti-viral vaccines. We have used the murine BALB/c monoclonal IgM anti-idiotope 87.92.6 to study the idiotope and antigen specificity, kinetics, dose dependence, adjuvant, carrier, and valency requirements of anti-idiotope-induced anti-viral antibody responses. These studies show that the production of high titer neutralizing antibody requires a lengthy (60 day) immunization protocol, which includes the use of adjuvant and multivalent anti-idiotope, and is dependent on anti-idiotope concentrations of greater than 50 micrograms. When administered in this manner anti-idiotope can stimulate serotype-specific antibody responses across species barriers at levels comparable with those obtained after inoculation with virus. The practical efficacy of these reagents and procedures is documented by the ability of maternal immunization with anti-idiotope to confer complete protection in neonates from a potentially lethal reovirus type 3 viral infection. 相似文献
23.
A subunit of choleragen and an erythrocyte ADP-ribosyltransferase catalyze the transfer of ADP-ribose from NAD to proteins and low molecular weight guanidino compounds such as arginine. These enzymes also catalyze the hydrolysis of NAD to nicotinamide and ADP-ribose. The kinetic mechanism for both transferases was investigated in the presence and absence of the product inhibitor nicotinamide by using agmatine as the acceptor molecule. To obtain accurate estimates of kinetic parameters, the transferase and glycohydrolase reactions were monitored simultaneously by using [adenine-2,8-3H]NAD and [carbonyl-14C]NAD as tracer compounds. Under optimal conditions for the transferase assay, NAD hydrolysis occurred at less than 5% of the Vmax for ADP-ribosylation; at subsaturating agmatine concentrations, the ratio of NAD hydrolysis to ADP-ribosylation was significantly higher. Binding of either NAD or agmatine resulted in a greater than 70% decrease in affinity for the second substrate. All data were consistent with a rapid equilibrium random sequential mechanism for both enzymes. 相似文献
24.
Stanley H. Faeth 《Oecologia》1985,68(1):34-40
Summary Patterns of herbivory over a two year period on Quercus emoryi (Fagaceae) were correlated with seasonal and yearly changes in tannin and protein content. Quantitative defense theory predicts that tannin and protein content in apparent plants should be negatively and positively correlated, respectively, with degree of herbivory. Most herbivory occurred early in the growing season, but the pattern varied between the two years. Tannin and protein content sometimes varied negatively and sometimes positively with degree of herbivory; they did not consistently covary with herbivory. Protein content was positively correlated with herbivory in 1981–1982 but not in 1982–1983. Condensed tannin content was negatively correlated with herbivory in 1981–1982 but not in 1982–1983. Hydrolysable tannin content was positively correlated with herbivory activity. Multiple regression analyses indicated these phytochemical variables explained either no significant variation in herbivory (1982–1983) or did so in a fashion opposite (1981–1982) to the predictions of the theory of quantitative defense.Feeding by oak insects was not solely a function of seasonal changes in quantitative defenses and nutrients. Obviously, population dynamics of the insects are sensitive to factors other than phytochemistry of the trees and I discuss other factors that can influence patterns of herbivory. 相似文献
25.
Dr. William R. Usinger George C. Clark Ellen Gottschalk Stanley Holt Robert I. Mishell 《Current microbiology》1985,12(4):203-207
A Gram-negative, psychrophilic bacterium, designated GB-2, was isolated from fetal calf serum and analyzed for its morphological, physiological, and biochemical characteristics. Gliding motility, sensitivity to actinomycin D, the presence of the pigment flexirubin and cytochrome c, growth on a variety of carbohydrates, the production of acid fermentation products, and a 34.9 mol% guanine+cytosine (G+C) content of bacterial DNA indicate GB-2 to be a member either of the generaCytophaga orFlexibacter. Growth of GB-2 was optimized in a simple defined medium to facilitate isolation and characterization of bacterial products. Liquid growth of GB-2 resulted in the release of significant quantities of a macromolecule free of both endotoxin and protein into the growth supernatant, which activated the proliferation of murine lymphocytes. The relationship between this bacterium and its end-products to other species of theCytophaga/Flexibacter group is discussed. 相似文献
26.
Epidermal growth factor 总被引:5,自引:0,他引:5
Stanley Cohen 《In vitro cellular & developmental biology. Plant》1987,23(4):239-246
27.
Stanley W. Watson Eberhard Bock Frederica W. Valois John B. Waterbury Ursula Schlosser 《Archives of microbiology》1986,144(1):1-7
A new chemolithotrophic nitrite-oxidizing bacterium, for which the name Nitrospira marina is proposed, was isolated from the Gulf of Maine. N. marina is a Gramnegative curved rod which may form spirals with 1 to 12 turns. Cells have a unique periplasmic space and lack intracytoplasmic membranes and carboxysomes. N. marina is an obligate chemolithotroph, but best growth is obtained in a mixotrophic medium. N. marina may be one of the most prevalent nitrite-oxidizing bacteria in some oceanic environments. Type strain is field with American Type Culture Collection (ATCC 43039). 相似文献
28.
H P Stanley 《Journal of ultrastructure research》1983,83(2):184-194
The ultrastructure of spermatozoa in Hydrolagus colliei is described. Basic similarities of structure to the sperm of the related elasmobranch fish are noted. The most significant features of sperm structure in Hydrolagus that differ from those of elasmobranch fish occur in the tail. The axoneme is eccentrically located and forms a double helix with a single longitudinal column. A second longitudinal column is reduced to a short remnant at the base of the tail. Microtubules within the axoneme are also helically disposed, a feature that is consistent with the rotating motion of the sperm. Abundant glycogen reserves are stored along the length of the tail. 相似文献
29.
Summary Variations in extractable cellulase and pectinase were followed during development of Hemerocallis (day lily) flowers. A peak in cellulase activity occurs in the pistil just prior to anthesis, followed by a 62% diminution in the enzyme activity at the time of anthesis. Cellulase activity, per mg protein, is about twice as high in the upper (stigma) portion as in the middle and lower one-third of the pistil tissues. No pectinase activity was detected in the pistil at all stages of development. Extractable pectinase is present at a maximum level in the very young ovary; it decreases rapidly as the ovary develops. Cellulase remains at a moderate level of activity throughout the development of the ovary, except for an increase of about 50% at pollination. Soluble cellulase and pectinase are found in mature pollen. The changes in the cell-wall hydrolytic enzymes in the pistil were pollen-tube growth. It may also promote changes in the cell walls of the pistil cells, although metabolism of the middle lamella during pollen germination is primarily controlled by pollen pectinases.A contribution of the Florida Agricultural Experiment Station, Journal Series No. 3070. 相似文献
30.