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61.
OBJECTIVE: To evaluate the circadian fluctuations in the risk of urinary calcium oxalate stone formation with regard to critical periods of crystallization. PATIENTS AND METHODS: Over a given time period, the Tiselius index depends on urine volume and urinary excretion of oxalate, calcium, citrate and magnesium. This crystallization potential was evaluated during three successive periods spread over 24 h for 25 recurrent stone-formers aged 16-76 years (mean 50) and 25 control subjects aged 27-71 years (mean 44). RESULTS: There was no significant difference in the value of the Tiselius index for all equivalent time periods in both groups of patients. The minimum value was recorded in the afternoon and the circadian pattern of the index illustrated the predominant importance of urinary output in its determination. Morning urinary concentrations and excretions of citrate, and nocturnal levels of magnesium were significantly higher in the stone-formers when compared with the control subjects. CONCLUSION: The lithogenic risk for calcium oxalate stones was maximal at the end of the night or during the early morning, when urinary output was minimal. This circadian study revealed abnormalities that are not apparent from non-fractionated 24 h urine samples, and which were potentially relevant to therapy.  相似文献   
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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   
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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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The present paper reports the results of an investigation regarding the design of a method for visually grading sawn timber of Argentinean Eucalyptus grandis. An empirical research project with four samples of beams and one sample of boards subjected to bending, one sample of boards subjected to tension and one sample of specimens subjected to compression, was carried out. The results obtained with specimens in structural sizes show the influence of the more important strength and stiffness reducing growth characteristics and allow to analyse different strength, stiffness and density profiles in comparison with the international strength class system established in the European standard EN 338. The research also reveals particularities for this timber species as the high ratio of modulus of elasticity and strength to density, in comparison with other deciduous species, among others.
Visuelle Festigkeitssortierung von Eucalyptus grandis aus ArgentinienFestigkeits-, Steifigkeits- und Rohdichteprofile und zugehörige Grenzwerte der Sortierparameter
Zusammenfassung Dieser Beitrag fasst die Ergebnisse einer Studie zusammen, in der die Möglichkeiten einer visuellen Festigkeitssortierung von Eucalyptus grandis aus Argentinien untersucht wurden. Die Untersuchung umfasste vier Teilstichproben mit Kanthölzern und eine Teilstichprobe mit Brettern in Biegeversuchen und jeweils eine Teilstichprobe mit Zug- bzw. Druckprüfkörpern. Die Ergebnisse der Versuche mit Prüfkörpern in Bauholzabmessungen zeigen den Einfluss der wichtigsten visuellen Sortierparameter und erlauben die Einteilung von Bauholz aus Eucalyptus grandis in unterschiedliche Festigkeitsklassen nach EN 338. Die vorliegende Studie zeigt darüber hinaus besondere Eigenschaften dieser Laubholzart wie das hohe Verhältnis von Elastizitätsmodul und Festigkeit zur Rohdichte.
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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   
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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   
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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   
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