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261.
Bovine red blood cells infected with Anaplasma marginale were introduced into cell line cultures from the mosquito Aedes albopictus. The cultured mosquito cells phagocytized both infected and uninfected red blood cells. The parasite remained viable, as determined by calf inoculations, for 21 days.  相似文献   
262.
The comparison of Histocompatibility Testing in 82 MS Patients and 368 controls is presented. The increase in HL-A7 and decrease in HL-A12 are confirmed. A significant increase in HL-A8 is reported. Mixed Lymphocyte Reaction confirms the LD7a increase (19 out of 24 Multiple Sclerosis patients tested); 100% of the patients bearing the HL-A7 determinant are found to be LD7a. The presence of specific Immune Response genes in Multiple Sclerosis is discussed.  相似文献   
263.
We report the scintigraphic-appearances of painful bipartite patella in 25-year-old man a 2 1/2 years history of unexplained patellar pain. Painful bipartite patella is a rare cause of chronic post-traumatic patellar pain. Bone scintigraphy, by demonstrating increased uptake by the painful accessory bipartite fragment, appears to be an imaging method of choice in the diagnosis of this condition.  相似文献   
264.
265.
Some questions of logistics in the case of holonic production systems   总被引:2,自引:0,他引:2  
The paper summarizes the logistic fundamentals of holonic production systems (HPSs). It drafts the features of HPSs essential from the logistic point of view and the requirements that have to be fulfilled for a given holonic system, and outlines the control of logistic system for an HPS. The paper also describes the logistic tasks of a common service centre, its operating domain and the advantages achievable in the course of its application. The second part of the paper deals with some optimization problems of purchasing logistics. Finally, the paper points out the savings obtainable by means of optimization of purchasing logistics.  相似文献   
266.
A protein that inhibits hemocyte aggregation has been isolated from hemolymph of Manduca sexta larvae and named hemocyte aggregation inhibitor protein (HAIP). HAIP has a M(r) = 50,000, pI = 8.5, and contains 7% carbohydrate. It is present at 230 +/- 20 micrograms/ml in hemolymph of day 3 fifth instar larvae. Antibodies to HAIP do not cross-react with M. sexta hemolin, which is similar in size and charge and also inhibits hemocyte aggregation. HAIP and hemolin have some similarity in amino acid composition and NH2-terminal sequence, but are different in overall secondary structure, as determined by CD spectroscopy. The concentration of HAIP in hemolymph is not affected by injection of larvae with bacteria. A protein of approximately 50,000 daltons that reacts with antibody to M. sexta HAIP is present in hemolymph of Bombyx mori, Heliothis zea, and Galleria mellonella. Although the function of HAIP in vivo is not yet clear, it may have a role in modulating adhesion of hemocytes during defensive responses.  相似文献   
267.
In this paper we applied mathematical techniques of non-linear dynamics, to an ECG signal. The first step is to compute the shift-delay time, via average displacement of the digital ECG. Phase space is constructed at a prescribed shift-delay and correlation dimension and dominant Lyapounov exponent versus the embedding dimension are monitored. This technique was applied to 5 healthy volunteers and 4 patients with VVI pacemaker.  相似文献   
268.
Bacterial antigen fragments complexed with class II major histocompatibility molecules (HLA-D) on antigen presenting cells (APCs) stimulate CD4+ T lymphocyte proliferation, presumably to protect the host. This study examined these responses to antigens of two periodontal pathogens in four groups (n = 15) of age- (young adult) and sex-matched Caucasian subjects with or without type 1 diabetes and moderate to severe periodontitis: Group DP = diabetics with periodontitis; Group DnP = diabetics without periodontitis; Group nDP = nondiabetics with periodontitis; and Group nDnP = nondiabetics without periodontitis. HLA-D phenotypes for each subject were determined by lymphocytotoxicity assays. T lymphocytes purified from peripheral blood were stimulated in cell culture with APC pulsed with various concentrations of tetanus toxoid, Porphyromonas gingivalis, and Capnocytophaga sputigena antigens. T lymphocyte reactivity (3H thymidine incorporation) was numerically lower in cultures from diabetics stimulated with unpulsed APC (not significant), and antigen-pulsed cultures showed low proliferation and no significant differences among groups. Stimulation indices in cultures from diabetic patients stimulated with P. gingivalis or C. sputigena, however, were significantly elevated at all antigen concentrations compared to nondiabetic cultures. The occurrence of HLA-DR4 was moderately associated with diabetes (P < 0.05) and highly associated with periodontitis (P < 0.001, log-linear model for categorical variables); and HLA-DR53 and HLA-DQ3 were significantly associated with periodontitis (P < or = 0.02). HLA-DR was crucial to lymphocyte stimulation (anti-HLA-DR blocking experiments), but the low peripheral blood T cell reactivity to antigens of periodontal pathogens could not be linked with HLA-D type or periodontitis susceptibility.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
269.
In rat experiments a new model of situational chronic stress, with the use of multicomponent natural stimulating influences, has been elaborated. The study revealed two subpopulations with longer and shorter lifespan in the group of stressed rats vs. control group. The survival of stressed animals was correspondent with the changes of adaptive indices. Thus the situational chronic stress has the geropromotive or geroprotective effect which depends on the organism's adaptive capacities.  相似文献   
270.
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