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41.
Electrocardiographic symptoms were evaluated in 53 patients with an additional left-ventricular chorda (ALVC), detected by two-dimensional echocardiography. Signs of early ventricular repolarization (EVR) were identified in 45 (84.9%) patients. A transverse ALVC was more common in EVR-free patients (87.5%), as compared to patients with ALVC + EVR combinations (51.1%; p less than 0.05). 相似文献
42.
In the isolated perfused rat pancreas, D,L-difluoromethylornithine, tested at a concentration of 3 mmol/L, failed to affect the release of glucagon and insulin caused, over 15 min stimulation, by either L-arginine or L-ornithine (2.0, 5.0 or 10.0 mmol/L) in the presence of either 3.3 or 5.6 mmol/L D-glucose. The inhibition of ornithine decarboxylase also failed to affect the release of glucagon provoked by either L-leucine (2 or 3 mmol/L) or L-glutamine (2 mmol/L) and the secretion of insulin stimulated by a rise in glucose concentration from 5.6 to 10.6 mmol/L. These data are interpreted to suggest that the rapid generation of polyamines from either L-arginine or L-ornithine does not play any significant role in the immediate glucagonotropic and insulinotropic action of these cationic amino acids. 相似文献
43.
44.
David A. Hughes Graham C. Smith Joyce E. Davidson Anna V. Murphy T. James Beattie 《Pediatric nephrology (Berlin, Germany)》1996,10(4):445-447
. Neutrophil-mediated tissue damage has been implicated in the pathogenesis of diarrhoea-associated haemolytic uraemic syndrome
(D+ HUS). This study evaluates priming and activation of the neutrophil oxidative burst in D+ HUS using chemiluminescent techniques.
Peripheral blood neutrophils from 11 children with acute D+ HUS were examined. No difference was found in the oxidative burst
of neutrophils from patients and controls. Serum elastase levels were measured in 8 patients and found to be significantly
elevated. Although elastase results suggest neutrophil activation, chemiluminescence studies do not confirm this in the peripheral
blood neutrophil. This does not support a significant role for circulating agents in priming and activating the peripheral
blood neutrophil.
Received August 17, 1995; received in revised form and accepted November 27, 1995 相似文献
45.
J. Viac C. Goujon L. Misery V. Staniek M. Faure D. Schmitt A. Claudy 《Photodermatology, photoimmunology & photomedicine》1997,13(3):103-108
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response. 相似文献
46.
R. LIBERMAN E.C. COMBE† V. PIDDOCK† C. PAWSON D.C. WATTS† 《Journal of oral rehabilitation》1995,22(6):445-449
SUMMARY Current standard specifications for the laboratory evaluation of denture base materials require subjective assessment of colour stability. This study evaluates a new objective measurement technique for translucent denture base materials, by comparing quantitative data with the results obtained from a standard subjective method. Preliminary work on three representative commercial acrylic materials resulted in the selection of a white background for the quantification of colour change of these translucent materials. One half of each sample was exposed to artificial sunlight for 24 h.
The colour of both exposed and unexposed resin was measured on the CIE L*a*b* scale using a photoelectric colorimeter. Significant changes in the b* and E* values (P < 0.001) were observed following light exposure. Objective data for a wide range of commercial materials were compared with the results of a subjective evaluation and it was shown that a change in b* of 1.5 units was discernable subjectively by eye for 100% of the cases. It is suggested that this method and limit value could form the basis of a new objective colour change specification for polymeric dental materials. 相似文献
The colour of both exposed and unexposed resin was measured on the CIE L*a*b* scale using a photoelectric colorimeter. Significant changes in the b* and E* values (P < 0.001) were observed following light exposure. Objective data for a wide range of commercial materials were compared with the results of a subjective evaluation and it was shown that a change in b* of 1.5 units was discernable subjectively by eye for 100% of the cases. It is suggested that this method and limit value could form the basis of a new objective colour change specification for polymeric dental materials. 相似文献
47.
T F Kruger J P Van der Merwe H J Odendaal F S Stander G M Grobler V A Hulme E L Erasmus K Coetzee M L Windt Y Swart 《Suid-Afrikaanse tydskrif vir geneeskunde》1990,77(12):634-636
The results of the in vitro fertilisation programme at Tygerberg Hospital for the period April 1983 to January 1988 are presented. Of the 1117 laparoscopies performed, 825 patients reached the transfer stage. A live-birth rate of 9.3% was achieved. The pregnancy rate after transfer of 4 embryos was 25.9% compared with 15.4% after 2 embryos and 10.8% after 3 embryos (P = less than 0.0001). The multiple pregnancy rate was 2.8% in the group receiving 2 embryos and 11.7% and 10.4% in those receiving 3 and 4 embryos, respectively. Of the 77 successful pregnancies (90 babies), 1 baby died at 34 weeks' gestation as the result of abruptio placentae due to preeclampsia and 1 cot death occurred. The only congenital abnormality encountered was a cleft palate. 相似文献
48.
V K Kudriashov V A Semenchenia 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》1990,(5):4-5
On the basis of the experience with treatment of more than 500 patients with sigmoid and rectal cancer, the informative value of the instrumental methods of investigation used for more precise definition of a stage of the disease is analysed. A scheme for rational examination of the patients is suggested. 相似文献
49.
50.
N V Kornilov B M Rachkov V I Kulik V M Kustov 《Vestnik khirurgii imeni I. I. Grekova》1990,145(8):62-66
A retrospective analysis of results of treatment of 104 patients with fractures of long tubular bones associated with injuries of peripheral nerves has shown complex therapy to be necessary. Main components of this treatment were biogenic stimulators, vitamin B12, spasmolytic and dehydration drugs in combination with electrophoresis with potassium iodide and thermal procedures. Rapid disturbance of conductivity of nerve trunks after trauma should be followed by revision of the given segment of the extremity in order to remove hematoma and make reposition of displaced fragments of the bone, which can provide recovery of the disturbed function of the nerve. 相似文献