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951.
The effect of the dose of oyster mushroom in the diet (1.0, 2.5, and 5.0%) and of the period of application (8, 16, 28, and 52 wk) on cholesterol accumulation in blood and body organs was studied in weanling male Wistar rats fed a diet containing 0.3% cholesterol. Reduction of cholesterol in serum and body organs was found to be dependent on the amount of dietary oyster mushroom administered. A negative correlation between the mushroom dose and cholesterol level was found after 8 and 28 wk of feeding (r=-0.9821 and -0.9803, respectively; P < 0.02 for both cases). The dose of 1% oyster mushroom did not affect cholesterol levels in serum or body organs. A significant reduction of cholesterol levels was observed in serum (31-46%) and liver (25-30%) at a dose of 5% of oyster mushroom for all periods. Reduced cholesterol content in very low-density lipoproteins (VLDL) was also observed at this level. The highest dose of oyster mushroom induced a decrease in conjugated diene levels in erythrocytes and an increase in the levels of reduced glutathione in the liver and stimulated the activities of catalase and glutathione peroxidase in the liver in the final period of the experiment.  相似文献   
952.
The structural properties of linear periodic discrete-time systems are analyzed in the periodic polynomial representation. It is shown that the classical polynomial approach for linear time-invariant systems can be extended to periodic systems. New definitions and properties are given in terms of skew polynomial rings and periodic difference algebra. Necessary and sufficient conditions for the characterization of reachability, controllability, observability and reconstructibility are given in this framework.  相似文献   
953.
Most of our knowledge concerning the presence of virus specific cytotoxic T lymphocytes (CTL) in early life has been provided by studies of CTL activities against human immunodeficiency virus type 1 (HIV-1) in infected infants born to HIV-infected mothers. HIV-specific cytolytic responses were found to be similar in perinatally infected children compared with adults, with respect to the nature of effector cells, protein recognized and the ability to control viral replication. CTL responses measured immediately after PBMC isolation (ex vivo activated CTL) were observed predominantly in children with no or mild symptoms, and the presence of in vitro activated CTL was found to be associated with the absence of severe symptoms during the first year of life and survival over 5 years.  相似文献   
954.
A retrospective review is presented of seven cases of epiploic appendagitis, with surgical confirmation in one case. The main clinico-analytical data and the US and CT findings are described, as well as the histopathologic features in the sole case that underwent surgical resection. We also calculated the frequency of this entity in patients undergoing emergency abdominal US on clinical suspicion of diverticulitis. In all seven cases the clinico-analytical evidence was nonspecific (localized acute abdominal pain and slight leukocytosis), mimicking in six cases the clinical presentation of sigmoid diverticulitis and in one case that of acute appendicitis. US imaging findings were characteristic: a hyperechoic mass localized under the point of maximum pain, adjacent to the anterior peritoneal wall and fixed during deep breathing. In none of the cases did color Doppler US show flow. CT findings were also typical and showed a mass with a peripheral hyperattenuated rim surrounding an area of fatty attenuation. Overall 7.1 % of patients investigated to exclude sigmoid diverticulitis finally showed findings of primary epiploic appendagitis. Primary epiploic appendagitis thus shows characteristic US and CT findings that allow its diagnosis and follow-up. This entity is much more frequent than previously reported, especially in patients referred for US to exclude sigmoid diverticulitis.  相似文献   
955.
GRA4, a dense granule protein of Toxoplasma gondii elicits both mucosal and systemic immune responses following oral infection of mice with cysts. We studied the antigenicity and immunogenicity of truncated and soluble forms of GRA4 expressed as glutathione S-transferase fusion proteins in Escherichia coli. Protein C (amino-acids 297-345) was particularly well recognized by serum IgG antibodies, milk IgA antibodies and intestinal IgA antibodies from T. gondii infected mice and by serum IgG antibodies from T. gondii infected humans and T. gondii infected sheep. One major B epitope was localized within the last 11 C-terminal residues of GRA4. A second epitope, recognized with lower frequency, was mapped within the region 318-334. In contrast, the N domain of GRA4 (amino acids 25-276) was poorly recognized. Oral immunization of C57BL/6 mice with N, C or NC (amino acids 25-276 fused to 297-345) in association with cholera toxin induced a significant production of serum anti-GRA4 IgG antibodies but a weak and inconsistent intestinal anti-GRA4 IgG antibody response and afforded partial resistance to oral infection with T. gondii. These results provide new molecular and immunological understanding of GRA4 and indicate that it is a potential candidate for oral vaccination against T. gondii.  相似文献   
956.
Enterotoxigenic Escherichia coli (ETEC) strains expressing only coli surface antigen 6 (CS6) have previously been isolated from patients with diarrhea, but the immunogenicity of CS6 has not been established in humans. We have detected CS6-specific immunoglobulin A responses in the feces and blood of patients convalescing from natural ETEC disease and of volunteers given an oral ETEC vaccine.  相似文献   
957.
958.
959.
The aim of this study was to assess the potential mechanism underlying the enhanced inflammatory processes during magnesium deficit. In this study, exacerbated response to live bacteria and platelet activating factors was shown in rats fed a magnesium-deficient diet. Peritoneal cells from these animals also showed enhanced superoxide anion production and calcium mobilising potency following in vitro stimulation. The latter effect occurred very early in the course of magnesium deficiency. These studies first showed that an abnormal calcium handling induced by extracellular magnesium depression in vivo may be at the origin of exacerbated inflammatory response.  相似文献   
960.
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