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The relation between 21 absolute body dimensions as well as 20 anthropometric indices and the length as well as the regularity of the menstrual cycle have been investigated in 156 patients of the hormone ambulance of the I. Universit?ts-Frauenklinik in Vienna. It turned out, that the length as well as the regularity of the menstrual cycle significantly negatively with the amount of the subcutaneous fat tissue. With an increasing amount of adipose tissue, the cycle became shorter and more regular. The importance of the subcutaneous fat tissue as a secondary hormonal gland has been discussed as one cause for these significant connections. Regarding the length- and height dimensions and the menstrual cycle patterns, no statistically significantly relationship could be observed between these two trait system. This is also true for the relationship between body built and the bleeding duration.  相似文献   
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Lysophosphatidylcholine (LPC) is formed by hydrolysis of PC in low density lipoprotein (LDL) and cell membranes by phospholipase A2 or by oxidation. Oxidized (ox) LDL activates endothelial cells, an effect mimicked by LPC. oxLDL also has the capacity to activate T and B cells, and antibody titers to oxLDL are related to the degree of atherosclerosis. The antigen in oxLDL responsible for its immune-stimulatory capacity is not well characterized, and we hypothesized that LPC was involved. We demonstrate herein the presence of antibodies against LPC, both of the IgG and IgM isotype, in 210 healthy individuals. This antibody reactivity was not specifically related to oxidation of the fatty acid moiety in LPC, since LPC containing only palmitic acid showed antibody titers equivalent to those of LPC containing unsaturated fatty acids. Antibody titers to PC were low compared with LPC, and hydrolysis of PC at the sn-2 position is thus essential for immune reactivity. There was a close correlation between anti-oxLDL and anti-LPC antibodies. Furthermore, LPC competitively inhibited anti-oxLDL reactivity, which indicates that LPC may explain a significant part of the immune-stimulatory properties of oxLDL. LPC, being a lipid, is not likely to be an antigen itself. Instead, LPC could form immunogenic complexes with peptides, which may induce and potentiate immune reactions in the vessel wall. This study adds to the evidence that LPC is an important component of oxLDL and emphasizes the potential role of phospholipase A2 in atherosclerosis.  相似文献   
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To respond to varying environmental demands the bone tissue in the body is under continual reconstruction throughout life. It is known that metallic elements are important for maintaining normal bone structure, but their roles are not well understood. More information about the effects of metal excess or deficiency is needed to help in the development of metallic bone implants and to improve the treatment of bone fractures and defects. The Oxford Scanning Proton Microprobe (SPM) is being applied in two studies involving metal ions in bone: (1) bone regrowth and bonding to titanium bone implants may be influenced by diffusion of Ti ions into the bone. We are using microPIXE to determine the metal ion content of bone developing in contact with implants of pure Nb, Ti and Ti alloys. (2) Bone lengthening as a surgical procedure is induced by fracturing the bone and allowing it to heal with a small gap between the fractured ends created by the use of external fixators. The gap can be slowly increased during the healing process to stimulate the production of new bone. The enzymes and other constituents of the developing bone need certain metals for their function. Using experimental animals we have studied the concentrations of the metals and whether a deficiency of trace metals limits the optimum rate of bone lengthening.  相似文献   
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Standard methods for the determination of iodine values of oils involve direct addition of halogen elements to the double bond. Since the reaction proceeds slowly there is a risk of substitution. A direct coulometrical titration method has been investigated.  相似文献   
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This article is in three sections. The first describes a number of radical new Swedish laws dealing with the working environment and ergonomics. The second section gives a method of problem identification which has been developed within Ergolab. Finally, a discussion is given of how better working conditions can be developed in close co-operation with the workers.  相似文献   
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The actin containing tropomyosin and troponin decorated thin filaments form one of the crucial components of the contractile apparatus in muscles. The thin filaments are organized into densely packed lattices interdigitated with myosin-based thick filaments. The crossbridge interactions between these myofilaments drive muscle contraction, and the degree of myofilament overlap is a key factor of contractile force determination. As such, the optimal length of the thin filaments is critical for efficient activity, therefore, this parameter is precisely controlled according to the workload of a given muscle. Thin filament length is thought to be regulated by two major, but only partially understood mechanisms: it is set by (i) factors that mediate the assembly of filaments from monomers and catalyze their elongation, and (ii) by factors that specify their length and uniformity. Mutations affecting these factors can alter the length of thin filaments, and in human cases, many of them are linked to debilitating diseases such as nemaline myopathy and dilated cardiomyopathy.  相似文献   
10.
The thermodynamics of a finite two-band superconductor has been studied by means of the Hubbard–Stratonovich representation of partition function in the static approximation. The temperature behavior of heat capacity depends substantially on interband interaction and volume. Interband coupling controls the distribution of thermal gap fluctuations on the temperature scale according to the changes in superconducting ordering.  相似文献   
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