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In the present study, the authors analysed the serial angiographical findings progressing to brain death and their relation to the intracranial pressure (ICP) and the cerebral perfusion pressure (CPP). Seventy two patients, from four to eighty four years old (fourty six males and twenty six females) admitted in the Department of Emergency Medicine, University of Tokyo Hospital during the period from January, 1981 to April, 1986, were studied. Their underlying diseases were supratentorial primary brain lesions except two cases with asphyxias which progressed to brain death. ICP was continuously measured and CPP was calculated as the pressure gradient between the mean arterial blood pressure (MAP) and ICP. The direct carotid angiography was performed to follow the cerebral circulation. Fourty five patients were subjected to barbiturate (pentobarbital sodium) therapy. The degree of the intracranial filling staged as "Non-filling", "Siphon-filling", "Partial-filling", "Delayed-filling", "All-filling" correlated significantly with ICP and CPP. These relationships, however, disappeared once ICP exceeded MAP. When "Non-filling" angiogram was obtained, clinical signs had already showed brain death. On the other hand, minimal flow ("Siphon-filling", "Partial-filling", "Delayed-filling") were still demonstrated in six brain death cases while ICP was approaching its "peak" value. This study showed that clinical diagnosis of brain death preceded the Non-filling phenomenon, suggesting that, for the demonstration of the cerebral circulatory arrest, the angiograms should be performed after the clinical diagnosis of brain death was established and CPP became zero. The evaluation of the extremely slow and minimal filling is still a matter of discussion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Daily profile of colonic motor activity was observed in 10 conscious dogs by means of extraluminal force transducers. Each dog was implanted with a set of seven strain, gauges, one on the terminal ileum and the remaining six on the colon equidistantly. The colonic motor activity was basically composed of migrating and non-migrating motor complexes at all six recording sites. Each motor complex was characterized by a tonic contraction superimposed by rhythmic bursts of phasic contractions. During fasted period these motor complexes recurred at a mean interval of 36 min, and a mean duration was 7 to 12 min. Those motor complexes which migrated over at least three recording sites were defined as "migrating", 72% of those observed at the most proximal sites (n = 2680) were migrating, and the remaining 28% were non-migrating. Of those migrating motor complexes 90.4% migrated caudad (iso-peristalsis), while only 9.4% migrated orad (antiperistalsis). During postprandial period the colonic motor complexes at all recording sites uniformly increased their frequency with shorter intervals. Different from the small intestine, the contractile patterns were essentially the same as those of fasted period. The postprandial acceleration of the colonic motor complexes seems to be compatible with gastrocolic response.  相似文献   
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Mucopolysaccharidosis type II (Hunter disease) is a lysosomal storage disorder caused by a deficiency of the enzyme iduronate-2-sulfatase. Varied clinical phenotypes of this disease have been described. To identify mutations in individual patients and to examine possible correlations between mutations and clinical phenotypes, we analyzed the iduronate-2-sulfatase gene in Japanese patients with different clinical phenotypes. Five missense mutations, S333L (severe), R468Q (severe), R468L (severe), W337R (intermediate), R48P (mild), and three nonsense mutations, W345X (severe), R443X (intermediate), Q531X (mild), were identified by the RT-PCR method. Transient expression in the enzyme-deficient fibroblasts revealed that all five missense mutant enzymes were synthesized as the normal-size precursor (73 kD), and the nonsense mutant enzymes were synthesized as truncated ones (W345X:54 kD, R443X:59 kD, and Q531X:69 kD), although stable mature enzymes (45–56 kD) were not detected by Western blot analysis. Further more, expression of the eight mutant cDNAs resulted in severe reductions of iduronate-2-sulfatase enzyme activity in comparison with a normal cDNA. © 1995 Wiley-Liss, Inc.  相似文献   
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Side-chain functionalized polysiloxanes were prepared via polymer-analogous esterification of poly[(3-chloroformylpropyl)methylsiloxane] with 4-(4-hydroxyphenylazo)nitrobenzene ( P1 ), 4-[4-(ω-hydroxyalkyloxy)phenylazo]nitrobenzene ( P2 – P4 ), 4-{4-[N-(2-hydroxyethyl)-N-methyl]anilinoazo}nitrobenzene ( P5 ), 4-(4-hydroxypiperidino)nitrobenzene ( P6 ), or 4-[4-(2-hydroxyethyl)piperidino]nitrobenzene ( P7 )., P1 , P3 , P4 and P5 exhibit liquid crystallinity, as deduced from differential scanning calorimetry, polarized microscopic observations and X-ray diffraction measurements. The liquid-crystalline phase of P1 and P5 is a nematic phase, and that of P3 and P4 is a smectic one. The second harmonic generation (SHG) measurement of a spin-coated film of P1 was carried out by the Maker fringe method using a Q-switched Nd:YAG laser (1064 nm). The SHG profile after the heat treatment of a spin-coated film suggests a perpendicular orientation of the mesogenic molecules to the glass substrate. The SH light intensity of a corona-poled film was 20-fold higher than that of a film which was only heated, though no differences were observed in their UV-vis absorption spectra. These findings suggest that the mesogenic-molecular dipole moments are aligned to the same direction in the crystalline or liquid-crystalline phase by a poling treatment.  相似文献   
16.
Septic shock remains a serious disorder associated with highmortality. Accumulating evidence indicates that TNF is a majorand essential mediator of endotoxin shock. We report here thatadministration of an antibody against CD18 dramatically reducedendotoxin-induced shock inrabbits as revealed by preventionof severe hypotension, metabolic acidosis and a pathologicalchange suggestive of disseminated intravascular coagulationwith concomitant inhibition of elevation of plasma TNF activity.The anti-CD18 antibody also inhibited the hypotension inducedby administering recombinant TNF. Furthermore, an antibody againsta ligand for CD18 complexes, intercellular adhesion molecule-1,also prevented TNF-induced shock as well as endotoxin shockinrabbits. These observations suggest that adhesion of leukocytesto endothelium may be of primary importance in the action ofTNF as well as in the production of TNF in vivo and that theantibody against adhesion molecules could be of therapeuticbenefit in life-threatening septic shock in humans.  相似文献   
17.
Reperfusion injury is a troublesome and unresolved problem in acute myocardial infarction and is believed to be associated with inflammatory reactions in which various types of cells and cytokines participate, in particular, macrophages and monocyte chemoattractant protein-1 (MCP-1). We designed this study to clarify the role and relationship of macrophages and MCP-1 in ischemic and reperfused heart. The number and distribution of macrophages and MCP-1 messenger RNA (mRNA) in the ischemic and reperfused rat heart were examined with in situ hybridization and immunohistochemistry. Myocardial samples were obtained at several times. In situ hybridization was performed with digoxigenin-labeled antisense RNA probe for rat MCP-1 mRNA, and immunohistochemistry was performed with antimacrophage antibody. Double staining with in situ hybridization and immunohistochemistry was also performed. The number of MCP-1 mRNA-positive cells increased after reperfusion and peaked at 3 hours after reperfusion. Early infiltration of ischemic tissues by macrophages was also observed at the time of the absence of an increase of MCP-1 mRNA-positive cells, and this infiltration was not significantly accelerated by reperfusion, but by ischemia itself. The numbers of both MCP-1 mRNA-positive cells and macrophages increased in the ischemic marginal region over time. From the result of double staining, and based on the cellular morphology and the distribution, the majority of MCP-1 mRNA-positive cells appeared to be activated macrophages. This suggests that macrophages may not be attracted to cardiac tissue only by MCP-1 and that MCP-1 may have some roles other than attracting macrophages into ischemic heart. It also suggests that macrophages and MCP-1 may play an important role in reperfusion injury and that MCP-1 may be one of the key molecules of reperfusion injury. These observations may contribute to the development of a new therapeutic approach to the prevention of reperfusion injury.  相似文献   
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The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis. © 1994 Wiley-Liss, Inc.  相似文献   
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