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31.
The effects of fish sera on the growth and fine structure of infective larvae of the eel-pathogenic acanthocephalanParatenuisentis ambiguus (Eoacanthocephala: Tenuisentidae) were studied under in vitro conditions using sera from the final hostAnguilla anguilla and from two accidental fish hosts as well as fetal calf serum. As controls larvae were also kept in medium in the absence of serum and in experimentally infected eels. Sera from the accidental fish hosts carp and rainbow trout exerted toxic effects on the acanthocephalans. Worms maintained in medium containing sera from these two fish were contracted and displayed inverted probosces. Moreover, the tegument exhibited vacuolization and the formation of necrotic areas, including lysis of the mitochondria. Due to these effects, the parasites died at 21 (rainbow trout) or 21–50 days (carp) postincubation. Eel sera had no toxic effect on the infective larvae. The growth of the larvae in medium depended on the composition of the latter, but was reduced as compared with that in the natural final host. Based on these results, we conclude that components of the hosts' blood sera play a role in the determination of the host specificity ofP. ambiguus. 相似文献
32.
D'Adamo P Welzl H Papadimitriou S Raffaele di Barletta M Tiveron C Tatangelo L Pozzi L Chapman PF Knevett SG Ramsay MF Valtorta F Leoni C Menegon A Wolfer DP Lipp HP Toniolo D 《Human molecular genetics》2002,11(21):2567-2580
Non-specific mental retardation (NSMR) is a common human disorder characterized by mental handicap as the only clinical symptom. Among the recently identified MR genes is GDI1, which encodes alpha Gdi, one of the proteins controlling the activity of the small GTPases of the Rab family in vesicle fusion and intracellular trafficking. We report the cognitive and behavioral characterization of mice carrying a deletion of Gdi1. The Gdi1-deficient mice are fertile and anatomically normal. They appear normal also in many tasks to assess spatial and episodic memory and emotional behavior. Gdi1-deficient mice are impaired in tasks requiring formation of short-term temporal associations, suggesting a defect in short-term memory. In addition, they show lowered aggression and altered social behavior. In mice, as in humans, lack of Gdi1 spares most central nervous system functions and preferentially impairs only a few forebrain functions required to form temporal associations. The general similarity to human mental retardation is striking, and suggests that the Gdi1 mutants may provide insights into the human defect and into the molecular mechanisms important for development of cognitive functions. 相似文献
33.
Indolent systemic mastocytosis with elevated serum tryptase, absence of skin lesions, and recurrent severe anaphylactoid episodes 总被引:2,自引:0,他引:2
Florian S Krauth MT Simonitsch-Klupp I Sperr WR Fritsche-Polanz R Sonneck K Födinger M Agis H Böhm A Wimazal F Horny HP Valent P 《International archives of allergy and immunology》2005,136(3):273-280
BACKGROUND: In contrast to aggressive mastocytosis, patients with indolent systemic mastocytosis (ISM) usually present with urticaria pigmentosa-like skin lesions. In those who lack skin lesions, mastocytosis is often overlooked or confused with endocrinologic, allergic, or other internal disorders. CASE REPORT AND RESULTS: We report on a 33-year-old male patient in whom severe hypotensive episodes occurred after contact with ants or yellow jackets. Since no specific IgE was detected, the serum tryptase concentration was measured and found to be clearly elevated (70 ng/ml). Consecutive staging and examination of the bone marrow revealed ISM. The patient was advised to circumvent insect contact, to take antihistamines on demand, and to carry an epinephrine self-injector for emergency events. In a retrospective analysis of 40 patients seen between 1988 and 2003, only 2 had a life-threatening mediator-related episode before ISM was diagnosed. CONCLUSIONS: Our report confirms the diagnostic value of tryptase in patients with suspected mastocytosis. In addition, the report suggests that the lack of typical skin lesions does not exclude an indolent form of mastocytosis even if the serum tryptase is clearly elevated. Finally, our case further shows that mastocytosis can be an important differential diagnosis to be considered in patients with unexplained anaphylactoid or other mediator-related symptoms. 相似文献
34.
Adjuvant activity of bacterial peptidoglycans on the production of delayed hypersensitivity and on antibody response 总被引:8,自引:0,他引:8
Purified peptidoglycans from various gram-negative bacteria can substitute for mycobacteria in Freund's type adjuvant. The effect of adjuvants on the production of delayed hypersensitivity in the guinea pig was studied with azobenzenearsonate? N? acetyl? L ? tyrosine as antigen. It was found that only a few μg of peptidoglycan per animal were needed. An adjuvant effect on antibody response to egg albumin was also obtained. 相似文献
35.
Thomas Dörner Sandra J. Foster Hans-Peter Brezinschek Peter E. Lipsky Thomas Dörner Sandra J. Fustcr Hons-Peltr Brtzinschtk Peter E. Lipsky 《Immunological reviews》1998,162(1):161-171
Summary: B cells are unique in that they generate and tolerate a high rate of mutations in their antigen receptor genes and employ these mutations as a basis of avidity maturation. The precise role of the mutational machinery versus subsequent selection in determining the frequency and distribution of mutations has not been fully analyzed. To address these issues, the influence of the intrinsic mutational machinery and subsequent selection on the frequency and distribution of mutations in the expressed human immunoglobulin repertoire was analyzed. Analysis of non-productively rearranged vH genes from individual human B cells provided an opportunity to examine the immediate impact of somatic hypermtitation without superimposed selective influences. Comparison with the frequency and distribution of mutations in the productively rearranged human VH genes permitted an estimate of the influences of subsequent selection. 相似文献
36.
Georg Manecke Hans-Peter Aurich Peter Gergs Hans Langisch 《Macromolecular chemistry and physics.》1974,175(6):1833-1845
Amphoteric ion exchangers with uniform structure were obtained by copolymerization of aziridinyl monomers followed by alkaline saponification of the ester groups of the polymers. The following compounds were copolymerized: Diethyl 2,4-di(1-aziridinyl)glutarate ( 1 ) with either diethyl (1-aziridinyl)succinate ( 4 ), diethyl (1-aziridinyl)fumarate ( 5 ) or dimethyl (1-aziridinylmethyl)succinate ( 6 ); diethyl ester of 3,3′-(1,4-phenylene) and 3,3′-(1,3-phenylene)di[3-(1-aziridinyl)propionic acid] ( 2a ) and ( 2b ), respectively, with either methyl (1-aziridinyl) acetate ( 7 ) or methyl (1-aziridinyl)propionate ( 8 ); dimethyl 3,6-di(1-aziridinyl)cyclohexane-1,2-dicarboxylate ( 3 ) with dimethyl 6-(1-aziridinyl)cyclo-2-hexene-1,2-dicarboxylate ( 9 ). Further the dioctylester of 3,3′-(1,4-phenylene)di[3-(1-aziridinyl)propionic acid] ( 10 ) was homopolymerized. The properties of the amphoteric resins were investigated. In particular the binding ability for Cu2⊕, Ni2⊕, Zn2⊕, and Mg2⊕ ions and the swelling ability were studied as function of the pH of the solution. The uptake of CU2+ ions was determined as a function of time. An average capacity for Cu2+ ions of 2,5 to 3,75 mmol/g of dry resin was found at pH 5,5–6. 相似文献
37.
D. P. Wolfer Roman J. Giger Marijana Stagliar Peter Sonderegger Hans-Peter Lipp 《Anatomy and embryology》1998,197(3):177-185
TAG-1/axonin-1 is a neuronal cell adhesion molecule of the immunoglobulin superfamily. It is predominantly expressed during
neural development and has been reported to be involved in axonal growth and pathfinding. Here, the expression of TAG-1/axonin-1
was investigated anatomically in the adult mouse brain by in situ hybridization using digoxigenin-labeled cRNA probes. Low
levels of TAG-1/axonin-1 could be detected in cerebellar granule cells, in tufted and mitral cells of the olfactory bulb,
and in pyramidal cells of area CA1 and CA3 of the hippocampus. We suspect that the expression of TAG-1/axonin-1 in these structures
of the adult brain may serve neural plasticity.
Accepted: 8 September 1997 相似文献
38.
39.
Andreas Obruca Karl Mock Wilfried Feichtinger Gerhard Lunglmayr 《Journal of assisted reproduction and genetics》1995,12(9):627-631
Purpose
Intracytoplasmic injection (ICSI) with testicular sperm was performed in 16 couples. All men had ductal obstruction and failed previous attempts of epididymal sperm microaspiration.Methods
Testis tissue was obtained by excisional biopsies and incubated in HEPES buffered EBSS medium over 24 h at 37C. Motile sperm (Grade 1 to 2) were recovered in 13 patients and fertilized a total of 62 oozytes. Four pregnancies were achieved.Results
One healthy boy and two girls (twin pregnancy) were born.Conclusions
The ongoing pregnancies revealed no fetal abnormalities on ultrasound scanning.Presented at the IXth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, April 3–7, 1995, Vienna, Austria. 相似文献
40.
Mock CN Abantanga F Cummings P Koepsell TD 《Bulletin of the World Health Organization》1999,77(12):955-964
Injury is an increasingly significant health problem in most low-income countries. However, strategies for preventing injury have not been well addressed. The present study was carried out to measure the incidence and outcome of various mechanisms of injury in Ghana in order to provide data for use in developing priorities for injury prevention efforts. For this purpose, using two-stage cluster sampling and household interviews, we surveyed 21,105 persons living in 431 urban and rural sites. During the preceding year, 1609 injuries resulting in one or more days of loss of normal activity were reported. Injury-related mortality was slightly higher in the urban (83 per 100,000) than in the rural area (53 per 100,000). However, the burden of disability from nonfatal injuries, as assessed by disability days, was higher in the rural (4697 disability days per 1000 person-years) than in the urban area (2671 days per 1000 person-years). Based on incidence rates and disability times, the major types of injury in the urban area were transport-related injury and falls. In the rural area, agricultural injuries predominated, followed by falls and transport-related injury. In rural and urban areas combined, 73% of motor vehicle-related injuries involved commercial vehicles. In this and other similar developing-country settings, injury prevention efforts should focus on falls and on transport safety in both urban and rural areas, with special attention being paid to commercial vehicles. In rural areas, agricultural injuries contributed the largest burden of morbidity, and should be a priority for prevention efforts. 相似文献