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11.
The body's equilibrium is possible thanks to the integration of skeletal structure, vertebrae, ligaments and muscles to form one functional unity. The forces which determine posture are composed of two complementary systems, the ligamentary and the muscular systems, which together determine a dynamic act of balance. The ligaments operate mainly against the visco-hydraulic pressure of the nucleus pulposus and bind the vertebral bodies together, whereas the muscles exhibit an antigravity function and support spinal stability. A mathematical model based on a mixed theory of directed and oriented curves is proposed. Through this model it is possible to develop an exact theory governing the deformation of the ligamentous spine. This theory should be universal in the sense that it can be used to supply the spine in any of its environments.  相似文献   
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Residual deficiency of brain performance in chronic alcoholics after a 5-year abstinency. Brain performance of a group of 43 chronic alcoholics abstinent since 5 years was tested. Some aspects of higher intellectual performance were found to be reduced as compared to a control population. The performance was also better than that of a group of chronic alcoholics abstinent for only one year. The residual deficiency of performance could be interpreted as a "functional psychosyndrome", resulting from chronic sensory deprivation on the base of the alcoholism.  相似文献   
14.
The present study was an initial attempt at understanding gender constancy in retarded children. Stories about retarded or nonretarded boys or girls were given to teachers and caretakers of retarded children and teachers of nonretarded children. The stories described children in four sex-stereotyped activities. Respondents rated each child in the stories on scales of typicality and acceptability. Results indicated that, while nonretarded children were rated as typical when engaging in sex-appropriate, desirable play activities, retarded children were rated as typical when engaging in undesirable activities, regardless of sex appropriateness. Different professional groups appeared to use different criteria when judging the children in the stories.  相似文献   
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The authors tested the virulence of K. ozaenae--its old museum strains, the freshly isolated ones and those passaged on meat-peptone agar; experiments were carried out on mice and chick embryos. To mice the culture was administered intraperitoneally, subcutaneously, intranasally, and to embryos--into the allantoic cavity and on the chorioallantoic membrane. Irrespective of the method of administration, the freshly isolated strains were highly virulent both for mice and for chick embryos. The virulence of such strains decreased in the process of passaging on the nutrient medium. Old museum strains were of low virulence for albino mice and avirulent for chick embryos. In comparing the virulent and avirulent strains there were found no differences in the antigenic structure and toxicity of the Boiven complex, cytoplasm, membrane, capsular polysaccharide or whole virulent and avirulent bacteria killed by heating.  相似文献   
17.
Chitosan (CS) and β-lactoglobulin (βlg) double-wall coating was designed as a shell structure to achieve prolonged release of core material in the gastrointestinal tract (GI) for potential food applications. A model core material, brilliant blue (BB) dye, was incorporated into CS as the primary wall material, and subsequently, denatured βlg, a secondary wall material, was used to coat the outer layer. The strongest interaction occurred between 0.5% (w/v) βlg and 0.5% (w/v) CS at pH 5.5 ± 0.1, where the opposite charges of CS and βlg formed a complex, which is especially favourable in acidic beverage systems. Under simulated stomach conditions, a denatured-βlg coat resisted acid conditions and pepsin hydrolysis for 2 h. While mimicking small intestine conditions, βlg was degraded by pancreatin, causing the release of BB-loaded CS to the intestinal fluid at a constant rate. The sustained release of core material later in the GI tract provided an optimal absorption rate in the small intestine.  相似文献   
18.
Thermodynamic and pH stability of recombinant human L- and H-ferritins wereprobed by differential scanning calorimetry and 8-anilino-1-naphthalenesulfonate (ANS) binding in the pH range 2-7. At pH 2.0-2.8 theywere dissociated into subunit monomers and in this pH interval theH-subunit displayed a single calorimetrically-revealed domain withproperties of a molten globule-like state: low enthalpy (6.3-8.0 J/g or169-172 kJ/mol) and Tm of thermal unfolding (approximately 50 degrees C), awide transition range (approximately 20 degrees C) and high ANS binding. Incontrast, at pH 2 the L-ferritin subunit showed two calorimetric domainswith Tm of 35 and 40 degrees C with similar unfolding enthalpies and withmoderate extent of interactions, as indicated by the ratio of calorimetricenthalpy (293.9 kJ/mol) and van't Hoff enthalpy (174.2 kJ/mol) for thethermal transition. A pH increase from 2.0 to 2.8 determined the couplingof the two domains into a single cooperative folding unit and drasticincrease of the transition temperature (from 37 to 80 degrees C). Thecontacts between the two domains in the L-subunit appeared to contribute toabout 30% of the total stabilization free energy. The unfolding enthalpies,heat capacity changes and pronounced ANS binding of the L-subunit at pH2.0- 2.8 indicated that part of the structure lacked 'meltable' tertiaryinteractions. The results indicate that H- and L-subunits are stabilized bylargely different intra-chain interactions with a critical contribution toL-subunit stability of embedded salt bridge(s) absent in the H-subunit.  相似文献   
19.
Systemic lupus erythematosus (SLE) is a chronic multi-organ autoimmune disease characterized by hyperactivated immune responses to self-antigens and persistent systemic inflammation. Previously, we reported abnormalities in circulating and bone marrow (BM)-derived plasmacytoid dendritic cells (pDCs) from SLE patients. Here, we aim to seek for potential regulators that mediate functional aberrations of pDCs in SLE. BM-derived pDCs from NZB/W F1 mice before and after the disease onset were compared for toll-like receptor (TLR) induced responses and microRNA profile changes. While pDCs derived from symptomatic mice were phenotypically comparable to pre-symptomatic ones, functionally they exhibited hypersensitivity to TLR7 but not TLR9 stimulation, as represented by the elevated upregulation of CD40, CD86 and MHC class II molecules upon R837 stimulation. Upregulated induction of miR-155 in symptomatic pDCs following TLR7 stimulation was observed. Transfection of miR-155 mimics in pre-symptomatic pDCs induced an augmented expression of Cd40, which is consistent with the increased CD40 expression in symptomatic pDCs. Overall, our results provide evidence for miR-155-mediated regulation in pDC functional abnormalities in SLE. Findings from this study contribute to a better understanding of SLE pathogenesis and ignite future interests in evaluating the molecular regulation in autoimmunity.  相似文献   
20.
The catalytic cracking of oilsand bitumen was performed over nanoporous materials at atmospheric conditions. The yield of gas increased with application of nanoporous catalysts, with the catalytic conversion to gas highest for Meso-MFI. The cracking activity seemed to correlate with pore size rather than weak acidity or surface area.  相似文献   
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