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61.
62.
M Barbero-Marcial E Azeka PR Camargo A Riso M Jatene J Soares R Snitcowsky JO Auler Júnior L Camargo S Santos V Coelho E Atik M Ebaid A Jatene 《Canadian Metallurgical Quarterly》1996,67(3):165-170
OBJECTIVE: To establish the prevalence of anticoagulant (AC) treatment, the indications, and the quality of care in primary health care. DESIGN: A cross-sectional study, in which patients on AC treatment were identified from laboratory records. The main and second indications for AC treatment and the last value of the AC-test were taken from medical records. SETTING: Eight Finnish health centres with a total population of 182091 inhabitants. RESULTS: A total of 1255 patients on AC treatment were identified, 48% of them men. The mean age was 68.9 years. The age-adjusted prevalence of AC treatment was 0.65%. The commonest main indication was atrial fibrillation (38%). It was the main or second indication in 591 patients (age-adjusted prevalence 0.30%). The next commonest main indication was deep vein thrombosis (15%), followed by pulmonary embolism (8%). A total of 274 (22%) patients were anticoagulated for cerebral circulatory disturbances. 86% of the latest prothrombin time values fell within recommended ranges. CONCLUSION: The prevalence of AC treatment in Finland seems to be high. The proportion of patients with atrial fibrillation is high, differing from the results in other countries. The monitoring of AC-treatment as the general practitioner's responsibility functions well. The quality of care is good, even in older age groups. 相似文献
63.
Obtaining high-quality radiographs of the proximal aspect of equine limbs is difficult because of the large muscles in these regions. The use of scintigraphy may provide further information. Abnormal bone scan findings of the ischial tuberosity or the third trochanter were found in 29 adult horses with obscure hind limb lameness between 1986 and 1996 at the Large Animal Clinic of the University of Bern. Each had abnormal radiopharmaceutical uptake but not all had radiographic changes. Radiopharmaceutical uptake ratios between the ischial tuberosity and the greater trochanter were calculated. The uptake ratio in a control group of 11 clinically sound horses was lower than in 11 lame horses with subjectively enhanced radiopharmaceutical uptake. 相似文献
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Only a few reports of adenomatoid odontogenic tumour (AOT) in Africans have been published. Clinical, histological and radiographic features as well as treatment results of thirteen new cases of AOT seen at the University College Hospital, Ibadan were reviewed. This lesion constituted 12.1% of odontogenic tumours. This study shows a male: female ratio of 1.2:1. This contrasts with the reported male: female ratio of 1:3 in the United States, Britain, Sri Lanka and Japan. The higher male incidence may be peculiar to Nigeria. Although the peak incidence was in the second decade of life, four patients were over 20 years of age. The mean age was 23.2 years for all patients. None of the patients presented with recurrence on follow up. 相似文献
66.
In all other species analyzed to date, the functionally active form of complement component C3 exists as the product of a single gene. We have now identified and characterized three functional C3 proteins (C3-1, C3-3, and C3-4) in trout that are the products of at least two distinct C3 genes. All three proteins are composed of an alpha-and a beta-chain and contain a thioester bond in the alpha-chain. However, they differ in their electrophoretic mobility, glycosylation, reactivity with monospecific C3 antibodies, and relative ability to bind to various surfaces (zymosan, Escherichia coli, erythrocytes). A comparison of the partial amino acid sequences of the three proteins showed that the amino acid sequence identity/similarity of C3-3 to C3-4 is 87/91%, while that of C3-3 and C3-4 to C3-1 is 51.5/65.5% and 60/73% respectively. Thus, trout possess multiple forms of functional C3 that represent the products of several distinct genes and differ in their ability to bind covalently to various complement activators. 相似文献
67.
MP Lewis M Clements S Takeda PL Kirby H Seki LB Lonsdale MH Sullivan MG Elder JO White 《Canadian Metallurgical Quarterly》1996,17(2-3):137-146
High doses of morphine produce a state of behavioural inactivity and muscular rigidity. This type of 'catalepsy' is clearly different from the state which is produced by the administration of neuroleptics, e.g. haloperidol. While haloperidol-induced catalepsy can easily be antagonised by NMDA receptor antagonists, there has been a report that the non-competitive NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d] cyclohepten-5,10-imine (MK-801) potentiates morphine-induced catalepsy. The aim of this study was to further examine the role of glutamate receptors in the mediation of morphine-induced catalepsy. To this end we coadministered morphine (20, 40, 60 mg/kg i.p.) with MK-801 (0.1 and 0.3 mg/kg i.p.), the competitive NMDA receptor antagonist DL-(E)-2-amino-4-methyl-5-phosphono-3-pentoic acid (CGP 37849) (2 and 6 mg/kg i.p.), or 1-(4-aminophenyl)-4-methyl-7,8-methylen-dioxy-5H-2,3- benzodiazepine (GYKI 52466) (2 and 4 mg/kg), an antagonist of the AMPA type of glutamate receptors, respectively. The degree of catalepsy was assessed using two different methods, the 'bar/podium/grid' test which is commonly used to measure neuroleptic-induced catalepsy, and a test for the presence or absence of righting reflexes after turning the animals into a supine position. It was found that in the 'bar/podium/grid' test coadministration of both NMDA receptor antagonists significantly and dose-dependently augmented morphine-induced catalepsy. The results using the AMPA receptor antagonist were less clear since the lower dose of GYKI 52466 tended to attenuate the morphine effect whereas the higher dose augmented morphine-induced catalepsy in some cases. While placing the animals on the bar and on the podium produced essentially the same results, the grid was found to be inapplicable for the measurement of morphine-induced catalepsy since the animals did not cling to the grid and fell off almost immediately after being released from the experimenter's hand. With respect to the righting reflexes it was found that the number of animals not showing these responses increased when MK-801 or CGP 37849 was coadministered with morphine. In contrast, most of the animals treated with GYKI 52466 and morphine displayed intact righting reflexes. It is concluded that glutamatergic transmission plays an important role in the mediation of morphine-induced catalepsy, though different to that of haloperidol-induced catalepsy, and that NMDA and AMPA receptors are differentially involved in different aspects of the associated behavioural state. 相似文献
68.
Botulinum neurotoxin (BoNT) types A and B are Zn2+-requiring endoproteases which potently block neurotransmitter release by cleavage of a 25-kDa synaptosomal-associated protein (SNAP-25) and synaptobrevin, respectively. Synaptobrevin is important for the exocystosis of catecholamines from dense-core granules and evidence is presented here for the involvement of SNAP-25 in this process in neuroendocrine cells. The effects of BoNT/A and BoNT/B on regulated secretion were compared in intact bovine chromaffin cells to investigate the consequences of cleavage of the different targets. Catecholamine secretion elicited by Ba2+, by elevated K+ concentrations or by nicotine was prevented by each toxin. A very good correlation was observed between the extents of SNAP-25 cleavage or synaptobrevin cleavage and inhibition of secretion by BoNT/A or BoNT/B, respectively, which indicates the importance of SNAP-25 and synaptobrevin in regulated exocytosis. Despite truncation of almost the entire SNAP-25 pool by exposure of the cells to BoNT/A, a residual fraction of secretion persisted that was induced by 20microM Ca2+ (and to a lesser extent by 1 mM Ba2+) following permeabilisation. Addition of more BoNT/A failed to reduce this level of secretion. Inclusion of Mg.ATP, which greatly enhanced secretion from permeabilised cells, was required for Ca2+-stimulated or Ba2+-stimulated BoNT/A-resistant secretion. Furthermore, synaptobrevin is essential for this response because the response was not observed in BoNT/B treated cells. In view of the ability of BoNT/E to abolish secretion from permeabilised cells and to delete 26 amino acids from the C-terminus of SNAP-25, it can be deduced that cleavage of only nine residues by BoNT/A does not prevent the resultant truncated form exhibiting attenuated activity under the conditions created by permeabilisation. This identification of a novel component of secretion from permeabilised cells should facilitate investigation of the functional interaction of SNAP-25 with other proteins involved in regulated exocytosis. 相似文献
69.
Spontaneous perforation of the esophagus is an uncommon and catastrophic event accompanied by extremely high morbidity and mortality. In a burn patient, diagnosis may be delayed because of painful burns that may mask the underlying problem. Diagnosis is dependent on a high index of suspicion and by inclusion of this entity in the differential diagnosis of chest pain. The authors report on a 45-year-old male who developed a spontaneous perforation of the esophagus while hospitalized for treatment of an 11% total body surface area burn. Diagnosis and initiation of appropriate treatment resulted in salvage of this patient. The pathophysiology of this disease and a review of the literature are presented. 相似文献
70.
Several investigators have recently reported that significant numbers of appropriately adapted mutants can be induced in bacterial and yeast strains by exposing stationary phase cells to specific environmental challenges. The resulting mutants are said to be both selection-induced and demonstrably non-random in origin; if this interpretation is correct, it is in direct conflict with the conventional neo-Darwinian view, which is that spontaneous mutants are truly random in origin and arise without the intervention of any overtly adaptive forces. We believe that there are alternative ways of accounting for the appearance of many (and probably all) of the additional mutants which proponents of the adaptive mutation theory claim are observed only after they applied the appropriate selective pressure. Having reviewed the available evidence, we consider that most (if not all) of the sorts of mutants which are said to have been induced following exposure of stationary-phase cells to intense selective pressure are equally likely to have been generated during the operation of certain well-known, conventional (and essentially random) cellular DNA repair processes. Evidence in support of our view can be found in the mainstream literature on the origins of spontaneous mutations. We also note that some of the molecular models which have recently been proposed to explain the production of selection-induced mutations preferentially (or even only) in genes of adaptive significance may turn out to be of considerable interest in their own right, even although the mutants whose origins they were intended to explain may turn out to have arisen in a manner which is totally independent of the conditions used for their selection. 相似文献