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91.
Myocardial infarction is frequently caused by acute coronary thrombosis. A previous study in patients three years after myocardial infarction has shown twice as high concentrations of the rapid inhibitor of plasminogen activator (t-PAI) as in healthy controls. The present study involves 29 patients with acute onset of myocardial infarction. Already on admission the mean concentration of t-PAI was 16.5 +/- 7.4 units/ml as compared to 7.5 +/- 2.3 in healthy controls. It is presently unknown if moderately elevated t-PAI levels contribute to a delay of the spontaneous thrombolysis of the coronary occlusion, thus promoting the development of myocardial infarction.  相似文献   
92.
A paleopathological maxilla and mandible with tooth agenesis were analyzed, focussing on the aetiology of the condition. The jaw material, derived from an adult mediaeval male, was examined by standard anthropological analyses, including radiography. In the maxilla there was agenesis of three permanent incisors and one premolar, and in the mandible of one permanent incisor and two permanent molars. Absence or marked reduction of the incisive foramen and the nasopalatine canal was found. The pattern of tooth agenesis was similar to the pattern observed in contemporary individuals, except for the agenesis of one permanent maxillary centreal insisor. It is suggested that the pronounced lack of the premaxillary area of the nasopalatine canals and the incisive foramen. As the condition can be ascribed to deviations in the prenatal developments, this investigation shows that embryological developmental patterns, which form the basis for the pattern of tooth agenesis, should be taken into account when evaluation dry bonde patholgy.  相似文献   
93.
The metabolic fate of methyl-branched iodo fatty acids was studied in primary culture of rat hepatocytes. We compared 16-iodo-2-R,S-methyl palmitic acid (2-Me), which can be rc="/content/u8m33434688rr051/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"> oxidized, with 16-iodo-3-R,S-methyl palmitic acid (3-Me) which can be rc="/content/u8m33434688rr051/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"> oxidized only after an initial rc="/content/u8m33434688rr051/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> oxydation and with 16-iodo-2,2-dimethyl palmitic acid (2,2-Me2) and 16-iodo-3,3-dimethyl palmitic acid (3,3-Me2) which cannot be rc="/content/u8m33434688rr051/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0"> oxidized at all. The normal fate of natural fatty acids was given by comparative experiments with [1-14C] palmitic acid. Monomethyl-branched iodo fatty acids were taken up in the same range as palmitic acid but more than dimethyl-branched iodo fatty acids. After a 15-h incubation, acido-soluble products (ASP) accounted for 75% of the radioactivity taken up as 16-iodo-2-methyl palmitic acid, 50% as other methyl-branched iodo fatty acids and only 30% as palmitic acid, which indicated that all the methyl-branched iodo fatty acids underwent a strong deiodination process. Fatty acids were esterified in the following order: palmitic acid >16-iodo-3-R,S-methyl palmitic acid>16-iodo-2-R,S-methyl palmitic acid>16-iodo-2,2-dimethyl palmitic acid>16-iodo-3,3-dimethyl palmitic acid. Cultured hepatocytes, labelled for 3 h with the various fatty acids and reincubated for 12 h without fatty acid, secreted large amounts of free dimethylbranched iodo fatty acids as compared to the monomethyl ones and palmitic acid. Only hepatocytes prelabelled with 16-[125I]iodo-2,2-dimethyl palmitic acid exhibited an appreciable secretion of labeled triglycerides, but at a lower rate than with [1-14C] palmitic acid. Conversely, the 16-iodo-monomethyl palmitic acids remained chiefly in hepatocyte triglycerides. Minute amounts of 16-iodo-methyl-branched-palmitic acids were found in hepatocyte or secred phospholipids as compared with palmitic acid. This metabolic fate of methyl-branched iodo palmitic acids argues against their utilization as imaging probes to monitor in vivo the synthesis and the secretion of triglycerides by the liver.  相似文献   
94.
The platelet-derived growth factor (ref='/search?dc.title=PDGF&facet-content-type=ReferenceWorkEntry&sortOrder=relevance' class='reference-link webtrekk-track' gaCategory="Internal link" gaLabel="PDGF" gaAction="reference keyword">PDGF) family consists of three different dimeric forms, AA, BB, and AB, of the two consitituent polypeptide chains, A and B. These interact with two different cell surface receptors that, in part, mediate different cellular functions. The various forms of ref='/search?dc.title=PDGF&facet-content-type=ReferenceWorkEntry&sortOrder=relevance' class='reference-link webtrekk-track' gaCategory="Internal link" gaLabel="PDGF" gaAction="reference keyword">PDGF, as well as the receptors, are expressed at high frequency in glioblastoma multiforme, and it has been suggested that the growth of this tumor might be affected by autocrine loops involving ref='/search?dc.title=PDGF&facet-content-type=ReferenceWorkEntry&sortOrder=relevance' class='reference-link webtrekk-track' gaCategory="Internal link" gaLabel="PDGF" gaAction="reference keyword">PDGF and its receptors. The present paper focuses on recent discoveries regarding the family of ref='/search?dc.title=PDGF&facet-content-type=ReferenceWorkEntry&sortOrder=relevance' class='reference-link webtrekk-track' gaCategory="Internal link" gaLabel="PDGF" gaAction="reference keyword">PDGF ligands and receptors, as well as reviews results concerning ref='/search?dc.title=PDGF&facet-content-type=ReferenceWorkEntry&sortOrder=relevance' class='reference-link webtrekk-track' gaCategory="Internal link" gaLabel="PDGF" gaAction="reference keyword">PDGF-dependent autocrine growth in experimental and spontaneous glioblastoma.  相似文献   
95.
Authors deal, in connection with their clinical cases, with the replacement of the fingers of the hand. Attention is called to the fact, that a minimal requirement of the reconstruction, performed on the severe, multiply amputated hand, should be the formation of a "basic hand", and that at the planning of such operations the aim may be the reconstruction of the function of the hand only. Among the methods presented the most modern methods, requiring microvascular surgical technique, are also shown. Although the right of using these is obvious, the older, however well proved methods should not be forgotten either. The possibilities of finger replantation are described didactically; considering the extent of this theme however authors did not strive to completeness.  相似文献   
96.
97.
encapsulating structures occurred inHolothuria tubulosa. Histologically, they were formed by nodules entrapping foreign material. By an internodular mass, two or more nodules were assembled in an encapsulating body that was brown-pigmented. This pigment could be melanin, since an enzyme (i.e., phenoloxidase) responsible for its synthesis was proven. The enzyme exerted oxidase activity against dopa, dopamine and norepinephrine but not against tyrosine. The components of the sea-cucumber phenoloxidase-activating system were present in the circulating cells, which could therefore be responsible for melanin deposition during processes of foreign-body encapsulation.  相似文献   
98.
Piglets born with spread-leg syndrome, a congenital weakness of the hindlimb adductors, were investigated to determine the site of lesion leading to limb impairment. Histological and immunohistochemical studies of the motor neuron unit showed no alterations but quantitative analysis revealed a reduction of axonal diameter and myelin sheath-thickness of the fibres innervating the adductors of the affected limbs. In the lumbar spinal cord a lack of myelination was observed in the tracts descending to the lower motor neurons. Recovery from the syndrome was accompanied by a catching-up of myelination with that of the controls. The spread-leg syndrome is due to a nutritional deficiency in the sow; thus it is assumed that the deficient maternal substances, mainly choline and methionine, are essential for the normal myelin production by spinal white matter oligodendrocytes of the fetus.  相似文献   
99.
Haemophilus influenzae lacks most of the biosynthetic enzymes for hemin synthesis. However, the organism has retained ferrochelatase activity, which we identified to be encoded by a hemH-homologous gene. In this report we characterize the growth physiology conferred by hemH mutations under infection and laboratory conditions.  相似文献   
100.
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