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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
961.
S A Ekestr?m S Gunnes U B Brodin 《Scandinavian journal of thoracic and cardiovascular surgery》1990,24(3):191-196
The effect of dipyridamole was investigated in 360 patients undergoing coronary bypass surgery. They were randomly allocated to receive dipyridamole (100 mg orally q.i.d. for 2 days preoperatively, 5 mg/kg body weight/24 h i.v. peroperatively and 100 mg orally q.i.d. for 1 year postoperatively) or placebo. Withdrawn from the study were 48 patients on dipyridamole and 57 on placebo. Cardiovascular and/or cerebrovascular events or need for anticoagulant treatment were the reasons for withdrawal in 22 (13%) of the dipyridamole, and 34 (18%) of the placebo group. Logistic regression analysis of risk factors influencing graft patency showed significant relation to peroperatively measured coronary blood flow. A positive trend of treatment was observed (p = 0.08). Vein graft blood flow measured during bypass surgery (245 patients) was significantly greater in the dipyridamole group (p less than 0.01). The occlusion rate was lower in vessels with peroperative blood flow greater than 30 ml/min (vein-marginal p less than 0.01, vein-dexter p less than 0.05, vein-diagonal 0.05 less than p less than 0.1). Dipyridamole increases coronary blood flow and graft patency following coronary bypass surgery. 相似文献
962.
Porous coated anatomic tricompartmental tibial components. The relationship between prosthetic position and micromotion 总被引:1,自引:0,他引:1
L Ryd A Lindstrand A Stenstr?m G Selvik 《Clinical orthopaedics and related research》1990,(251):189-197
Micromotion of the tibial component, both as migration over time and as inducible displacement in response to external physiologic forces, was studied in 20 cases of gonarthrosis. The patients had Porous Coated Anatomic primary total knee arthroplasty and were followed for four years. All cases but one were clinically successful. Thirteen components were inserted without cement, while in seven, high-viscosity Palacos cement was used. Full postoperative weight bearing was allowed in all cases. During the first year, noncemented components migrated a mean of 2.6 mm, while cemented components migrated a mean of 1.1 mm. About 1 mm of migration of noncemented components was in the downward direction, i.e., subsidence occurred, mostly during the first year. After one year, the noncemented components had stabilized more than the cemented ones. There was a significant correlation between the migration after one year and the postoperative prosthetic position and alignment of the leg. A mean maximum inducible displacement (the total vector displacement of the prosthetic marker that moved the most) of 0.7 mm and 0.4 mm was found for noncemented and cemented components, respectively. The micromotion found was of the same magnitude as that for other cemented and noncemented prosthetic systems previously reported. 相似文献
963.
In a group of 59 consecutive ICU trauma patients with blunt chest injury and considerable injury severity (ISS = 29) a three-staged therapeutic approach was followed, depending seriousness of chest injury, overall injury severity and age. Stage 1: i.v. analgesia and conventional respiratory therapy. Stage 2: continuous epidural analgesia (local anesthetics and opiates) and intermittent CPAP (continuous positive airway pressure) by face mask. Stage 3: Endotracheal intubation and internal pneumatic stabilization of the chest, preferably spontaneous breathing. Only 44% of the patients needed intubation, and none died. The authors recommend this three-step approach towards blunt chest injury and serial rib fractures. 相似文献
964.
Ralph M. Trüeb Marcus Pericin Jürg Hafner Günter Burg 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1997,48(4):266-269
Zusammenfassung
Bei der Bündelhaar-Follikulitis (tufted hair folliculitis) handelt es sich um eine durch Staphylococcus aureus verursachte, chronisch entzündliche und vernarbende Haarbodenerkrankung, die charakterisiert ist durch das umschriebene Auftreten
von Bündelhaaren. Histopathologisch findet sich eine perifollikul?re Entzündung im oberen Bereich der Haarfollikel unter Aussparung
der tiefen Follikelanteile. Innerhalb der Entzündungsareale münden mehrere Haare aus getrennten Haarwurzeln in ein gemeinsames
Infundibulum mit dilatiertem Ostium. Das Krankheitsbild ist als eine Erscheinungsform der Folliculitis decalvans capillitii
Quinquaud anzusehen, bei der die Auffassung besteht, da? die Infektion mit Staphylococcus aureus den pathogenetischen Initialfaktor darstellt, und Besonderheiten der Follikelanatomie und Immunantwort die individuelle Morphologie
bestimmen: Dabei ist anzunehmen, da? die Ausbildung fl?chig atropher Narben mit vollst?ndigem Untergang der Hautanhangsgebilde
(im Falle der Folliculitis decalvans) oder das Auftreten von Haarbündeln (im Falle der Bündelhaar-Follikulitis) von der Tiefe
und dem Destruktions-Potential des Entzündungsinfiltrates abh?ngen. Die Behandlung der Bündelhaar-Follikulitis ist nicht ganz
unproblematisch: Die prolongierte und wiederholte Gabe staphylokokken-wiksamer Antibiotika vermag den Krankheitsverlauf zu
stabilisieren. Bereits vorhandene Haarbündel mit einer besonders hohen Rezidivneigung sollten aber – wie im vorgestellten
Fall – nach M?glichkeit chirurgisch exzidiert werden.
Summary A case of tufted hair folliculutis presenting as circumscribed, tender and inflamed areas in the occiput with residual tufted follicles in a 28-year old man is reported. Tufted hair folliculitis is a characteristic localized scarring bacterial folliculitis of the scalp due to Staphylococcus aureus. Histopathological studies reveal perifollicular inflammation around the upper portions of the follicles sparing the hair root level. Within areas of inflammation, several follicles converge toward a common follicular duct with a widely dilated opening. Currently, tufted hair folliculitis is considered a variant of folliculitis decalvans of Quinquaud. Staphylococcal infection is believed to be an initial causative factor, and underlying differences in follicular anatomy or host response may be important in determining which reaction pattern occurs in an affected individual. The development of atrophy with loss of adnexal structures (in folliculitis decalvans) or of hair tufts (in tufting folliculitis) may depend upon the depth and destructive potential of the inflammatory process. The therapeutic approach is problematic; prolonged treatment with oral antibiotics may stabilize the disease, but good and at times more definitive results (as in the presented case) have been reported after radical surgical excision of the involved areas.
Eingegangen am 2. April 1996 Angenommen am 7. Juni 1996 相似文献
965.
M A Maw S John S Jablonka B Müller G Kumaramanickavel R Oehlmann M J Denton A Gal 《Journal of medical genetics》1995,32(5):396-398
Oguchi disease is a rare autosomal recessive form of congenital stationary night blindness. The condition is associated with fundus discolouration and abnormally slow dark adaptation. Earlier studies suggested that the 48 kD protein S antigen may be involved in the recovery phase of light transduction. Previous cytogenetic and linkage studies have localised the S antigen gene (SAG) to chromosome 2q37.1. In the present study markers which map to distal chromosome 2q were typed in an inbred Oguchi pedigree. The segregation data obtained suggested that the affected subjects are homozygous by descent for a region between D2S172 and D2S345. An intragenic SAG polymorphism was homozygous in all affected people and a recombination event suggested that SAG maps proximal to D2S345. Collectively, these findings support the hypothesis that a defect in S antigen may be responsible for Oguchi disease. 相似文献
966.
This study investigated the relationship between the direction of lateral eye shifts evoked by bilateral visual stimulation, on the one hand, and verbal vs visuospatial performance, on the other. In males a negative correlation was found between verbal relative to spatial accuracy and the ratio of leftward eye movements. No such relationship was found in females. Additionally, in males body mass index was smaller for those who displayed a greater ratio of leftward eye movements. It was concluded that visually evoked lateral eye shifts might reflect hemispheric preference, similarly as lateral eye movements obtained during the widely used questioning procedure. However, the procedure used in this study for evoking lateral eye shifts seems to be free of some methodological problems of the traditional procedure and is more easy to standardize. 相似文献
967.
Endotoxins in cardiopulmonary bypass 总被引:5,自引:0,他引:5
L Nilsson L Kulander S O Nystr?m O Eriksson 《The Journal of thoracic and cardiovascular surgery》1990,100(5):777-780
Endotoxins are biologically active substances derived from the cell wall of degraded gram-negative bacteria. Since sterile water may also contain large amounts of endotoxins, these are easily introduced into the manufacturing processes of technical medical material, such as the extracorporeal components used in cardiopulmonary bypass. In hemodialysis, the presence of endotoxins has been related to untoward effects in patients. Using the limulus amebocyte lysate test, we determined the serum concentration of endotoxin in 42 patients undergoing coronary bypass operations. The values increased during cardiopulmonary bypass, exceeding the normal range of 0 to 20 ng/L in 10 patients with a maximum of 82 ng/L, which probably indicates endotoxin release from the extracorporeal equipment. We found no obvious relation to postoperative morbidity. The endotoxin levels of this study are considerably lower than those reported in two other studies of patients having cardiopulmonary bypass. This might be due to less intraoperative contamination but possibly also to differences in analytic methods. 相似文献
968.
In order to investigate the DA activity in polycystic ovary syndrome (PCOS) we studied the response of LH, FSH and PRL to a dopamine receptor antagonist metoclopramide (MCP-10 mg iv) in 12 PCO subjects (7 with normal and 5 with elevated levels of prolactin). The prolactin and LH responses to metoclopramide were compared to those obtained in 6 normal cycling women. Although a significant increase in PRL levels was documented after MCP administration in all PCO patients and normal cycling women (p less than 0.01), the highest increment in PRL levels was observed in normoprolactinemic PCO subjects. In contrast a blunted PRL response was observed in hyperprolactinemic PCO patients. There was a negative correlation between basal PRL levels and the maximum net increase in PRL after MCP. In both groups of PCO subjects MCP administration caused initial decrease in LH levels followed by an increase after 4 h. In hyperprolactinemic PCO patients this observed MCP effect on LH was more pronounced and significantly different in comparison with normoprolactinemic PCO patients (p less than 0.01). MCP administration did not cause significant acute alterations in LH levels in normal cycling women and no significant FSH changes in either PCO or control subjects. A relative dopamine deficiency might cause hypersecretion of PRL and LH in patients with PCOS and hyperprolactinemia. 相似文献
969.
970.
Ohne Zusammenfassung 相似文献