Abnormal structures

Although UTIs in men are not always complicated by definition, due to the relative infrequency of UTIs in men compared to women, an abnormality (structural or functional) should be suspected and therefore treated as a probable complicated infection until proven otherwise. For this reason, men should not be treated with a single dose or short course of therapy if diagnosed with a UTI. Typically these patients will receive 2 weeks of therapy, and in situations of failure may be treated up to 6 weeks, particularly if a prostatic source of infection is... 

Hyperproliuerative thickening, abnormal structural organization Psoriasis... 

Frischer, L. E., Hagen, F. S., and Garber, R. L. (1986). An inversion that disrupts the Antennapedia gene causes abnormal structure and localization of RNAs. Cell 47 1017-1023. 

Most synthetic and natural polymers degrade when exposed to solar ultraviolet (UV) radiation (1-5). In synthetic polymers degradation is generally caused by the presence of photosensitive impurities and/or abnormal structural moieties which are introduced during polymerization or in the fashioning of the finished products. The presence of groups such as ketones, aldehydes, peroxides and hydroperoxides are implicated in polymer degradation (1-5). 

As illustrated in the diagram below, domain swapping can also result in indefinite polymerization to form linear supramolecular structures. These may correspond to present-day polymers of proteins such as microtubules, or they may represent abnormal structures, like the straight and paired-helical filaments in the neurofibrillary tangles observed in the brain tissue of those afflicted with Alzheimer s disease. 

Some metals crystallize in more than one structural type, which means that there are two alio tropic modifications. The metals marked do not conform precisely to the closest-packed structure, but deviate slightly from it. Uranium, manganese, gallium and indium have very abnormal structures, and the last two are transitional between metallic and non-metallic elements of the carbon group. The picture presented by the metallic structures is utterly different from that of elements of the four last groups of the periodic system. The homopolar bonds of these latter strive to produce a state in which the number of neighbours of each atom is determined by its valency. In the other elements, however, forces appear to be acting that tend to surround each atom with as many other atoms as possible. 

The principal interest of the rubber hydrochloride structure (apart from its bearing on the theory of the relation between the physical properties and the molecular structure of polymers) is that it formed the first test of validity and usefulness of the principle of staggered bonds. Abnormal structures f In all the structures considered so far two... 

Replacement of Labile Chlorines. When PVC is manufactured, competing reactions to the normal head-to-tail free-radical polymerization can sometimes take place. These side reactions are few in number yet their presence in the finished resin can be devastating. These abnormal structures have weakened carbon—chlorine bonds and are more susceptible to certain displacement reactions than are the normal PVC carbon—chlorine bonds. Carboxylate and mercaptide salts of certain metals, particularly organotin, zinc, cadmium, and antimony, attack these labile chlorine sites and replace them with a more thermally stable C—O or C—S bound ligand. These electrophilic metal centers can readily coordinate with the electronegative polarized chlorine atoms found at sites similar to structures (3—6). 

Galanakis, D. K. (1993). Inherited dysfibrinogenemia Emerging abnormal structure associations with pathologic and nonpathologic dysfunctions. Semin. Thromb. Hemost. 19, 386—395. 

Atomic contacts that are not abundant in the protein structure database are good indicators of local model-building problems [63]. Atomic contacts are observed because they are energetically favored. Real structures cannot tolerate too many unfavorable interactions. Unis fora model to be correct, only a few infrequently observed atomic contacts are allowed. This quality control of local packing has proven to be the most powerful tool for the detection of abnormal structures. 

Berthelsen JG Skakkebaek NE (1983) Testicular cancer Abnormal structure and function of the contralateral testis. Int J Androl, 6 209-211. 

Langston C (1983) Normal and abnormal structural development of the human lung. In Kavlock RJ Grabowski CT eds. Abnormal functional development of the heart, lungs, and kidneys Approaches to functional teratology. New York, A.R. Liss, pp 75-91. 

Crossing-over or recombination at homologous loci is a normal process and results in a redistribution of parental genes. However, mis-pairing may lead to the formation of abnormal structural genes whose... 

One explanation of these results is that choline deficiency causes production of lipoproteins with abnormal structures, which results in an inability of the liver to export TGs to the bloodstream. Another theory is that choline deficiency produces defects in the structure of the endoplasmic reticulum, the network of tubules used for the synthesis of proteins and protein complexes destined for secretion from the cell. The membrane walls of the ER consist of phospholipids. Because all membranes contain phosphatidylcholine, a choline deficiency might be expected to result in defects in all membranes of the body, including those of the ER,... 

The use of fluoride as a drug for periods of 2 to 5 years has been shown to lead to increases in bone density in the spine, but little or no effect elsewhere. The increase in bone density may be equivalent to 3S% of the initial bone density. One serious problem remains with this use of fluoride. Some studies have shown thal treatment results in a decrease in the bone fracture rate (the desired effect) other studies have shown that the increase in bone density is associated not with a reduction in the fracture rate but in the formation of abnormally structured and unusually fragile bone. 

Silicon appears to be required for the normal synthesis of the organic matrix of bone and for its normal calcification. The silicon in the blood serum occurs entirely as silicic acid. Osteoblasts may contain the highest concentrations of silicon of all the cells of the body. Within these cells, silicon occurs mainly in the mitochondria. Silicon deficiency in animals results in bones with abnormal structures. These abnormalities include thinner oc rtical bone, reduced bone flexibility, and flattened cranial bones. Silicon deficiency also affects cartilage, and results in a dramatic reduction in the ividth of the epiphyseal cartilage (Carlisle, 1985). 

A 32-year-old man developed infertility and a low sperm count (under 50 x 10 /1), with no motile sperm, less than 10% viability, and 100% with abnormal structure while taking valproate monotherapy for 5 years (96). Within 4 months of switching to felbamate, he and his wife conceived twin girls, and the sperm abnormalities were largely reversed. 

Figure 10.59). A sulfhydryl group can spontaneously condense with another sulfhydryl group, forming a disulfide bond. In many cases, the formation of a disulfide bond involving two residues of cysteine in a protein is required for the normal functioning of the protein and is desirable. In other cases, the disulfide bond represents an abnormal structure and may be reversed by thioltransferase. 

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