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1.
When the roots of Vicia faba L. beans were subjected to hypoxic stress, the activity of H+-ATPase on the peribacteroid membrane, as well as the transport of dicarboxylates (malate and succinate) mediated by this enzyme, decreased. Since malate and succinate are the main carbon-containing metabolites involved in the energy supply to bacteroids, this caused a change of the relation type from mutualism to commensalism, and the domination of the eukaryotes over the prokaryotes consequently increased.  相似文献   
2.
The results of pathomorphological investigation of the disease in small laboratory animals experimentally induced by the EMC-70 strain of encephalomyocarditis virus isolated from monkeys are presented. Irrespective of the mode of virus injection, the newborn and juvenile mice developed some lesions in the brown fat, transverse-striated muscles, as well as in the brain and heart. In guinea pigs the changes were characterized by the development of severe myocarditis and encephalitis accompanied by viral antigen accumulation. The disease induced by the EMC-70 strain could not be differentiated from the Coxsackie infection by the pathomorphological data. This fact should be taken into consideration in solving some problems pertinent to pathoanatomical diagnosis of viral diseases.  相似文献   
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Combined action of doxycycline and mytilan, a natural polysaccharide, on the primary immune response to the antigen of the tularemia vaccinal strain in CBA mice was studied. The polysaccharide was used to compensate the immunosuppressive effect of doxycycline high doses on the humoral immune response. The maximum stimulation of the antibody titers as compared to the controls (more than 250 per cent) was observed when mytilan was administered simultaneously with or prophylactically 3 days prior to the antibiotic in doses of 2.5 and 25 mg/kg. The use of mytilan in combination with doxycycline high doses made it possible to compensate the antibiotic-induced decrease of DTH and even to stimulate it as compared to the controls. The highest levels of DTH (150 per cent against the control) were observed when mytilan was administered prophylactically in doses of 2.5 and 11.25 mg/kg 3 days prior to immunization. Mytilan had the highest stimulating effect on antibody production. The combined use of doxycycline and mytilan was characterized by significant stimulation of antibody production and DTH when the dose/time regimens were rational.  相似文献   
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6.
In the suboesophagal complex of Helix pomatia, a neurone (LPa33) was identified as a member of the system of neurones which trigger the defensive behaviour, one of the most responsive components of which is the reaction of the pneumostome closing. Spike activity of the LPa33 unit triggers the pneumostome closing in the form of a coordinated reaction of certain pneumostome muscles, which compose the neurone motor field. It is suggested that neurone LPa33 innervates separate muscles of its motor field directly with its axones.  相似文献   
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Limited knowledge of the behavior of stem cells in culture seems to be one of the reasons for problems in their successful introduction to applied medicine. To address this issue, we studied in vitro interaction of human mesenchymal stromal cells (MSCs) with various substrates (plastic, type I collagen, fibronectin, and mixtures of these proteins at various ratios) for 16–18 h after cell plating. Several cell-morphology features, such as area, perimeter, spreading coefficient, and polarization coefficient were determined. It is shown that MSCs specifically respond to the substrate and consist of several groups. Collagen and fibronectin have opposite effects on polarization and spreading of the cells. Collagen preferably enhances polarization of the cells, whereas fibronectin stimulates proportional spreading of cells. The combined effect on the cells of the collagen-fibronectin mixture cannot be considered as a simple additive effect. We assume that variations in the ratio of ECM proteins may be one mechanism of a directed action on stem cells.  相似文献   
9.

Background

Peripheral artery disease (PAD) is an important global health problem and contributes to notable proportion of morbidity and mortality. This particular manifestation of systemic atherosclerosis is largely under diagnosed and undertreated. For sustainable preventive strategies in a country, it is mandatory to identify country-specific risk factors. We intended to assess the risk factors of PAD among adults aged 40–74 years.

Methods

This case control study was conducted in 2012–2013 in Sri Lanka. Seventy-nine cases and 158 controls in the age group of 40–74 years were selected for the study in order to have case to control ratio 1:2. The criterion for selecting cases and control was based on Ankle brachial pressure index (ABPI). Cases were selected from those who had ABPI 0.85 or less (ABPI ≤0.85) in either lower limb. Controls were selected from those ABPI score between 1.18 and 1.28 in both lower limbs. Only newly identified individuals with PAD were selected as cases. Controls were selected from the same geographical location and within the 5 year age group as cases.

Results

The history of diabetes mellitus more than 10 years (OR 5.8, 95% CI 2.2–14.2), history of dyslipidemia for more than 10 years (OR 4.9, 95% CI 2.1–16.2), history of hypertension for more than 10 years (OR 3.8, 95% CI 1.8–12.7) and smoking (OR 2.9, 95% CI 1.2–6.9), elevated HsCRP (OR 3.7, 95% CI 1.2–12.0) and hyperhomocysteinemia (OR 3.0, 95% CI 1.1–8.1) were revealed as country specific significant risk factor of PAD.

Conclusions

Diabetes mellitus, hypertension, dyslipidemia, smoking as well as elevated homocysteine and HsCRP found as risk factors of PAD. Longer the duration or higher level exposure to these risk factors has increased the risk of PAD. These findings emphasis the need for routine screening of PAD among patients with the identified risk factors.
  相似文献   
10.
Russian Journal of Plant Physiology - On the preparations of symbiosomes isolated from broad bean (Vicia faba L.) root nodules, the transport activity of symbiosome membrane (SM) Ca2+-ATPase...  相似文献   
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