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961.
962.
NM Nadezhina IA Galstian LA Suvorova VN Pokrovskaia GP Gruzdev VG Leliuk AB Kutuzova ZhN Rtishcheva IV Uvacheva 《Canadian Metallurgical Quarterly》1997,37(5):780-786
Chemical prophylaxis is known to reduce the venographic prevalence of deep-vein thrombosis (DVT) after total knee replacement (TKR), but it is uncertain whether this affects the incidence of symptoms. Further analysis depends on the basic epidemiology of thromboembolic symptoms. We therefore studied the pattern of such symptoms in a consecutive series of 1000 patients with primary TKR, with particular reference to risk factors and prophylaxis. We reviewed all the clinical records and contacted all the patients individually, noting risk factors, prophylaxis, symptomatic pulmonary embolus (PE) or DVT and its timing, death and its causes, and all complications. All the patients wore antiembolism stockings, 83% had regional anaesthesia and 33.9% had chemical prophylaxis. One patient died from PE on the day of surgery, having had no prophylaxis giving a rate of 0.1% (95% CI 0.003% to 0.56%). Symptomatic, radiologically confirmed thromboembolism (VTE) was common with a rate of 10.6% (95% CI 8.7% to 12.5%). There was a similar incidence of VTE in those with and without chemical prophylaxis (10.1% v 10.5%, RR 0.96, NS). VTE was more common in patients with risk factors (15.1% v 9.5%, RR 1.59, p = 0.02) and tended to occur earlier in this group (median day of onset 5 v 7, p = 0.01). Chemical prophylaxis did not reduce the frequency of symptomatic thromboembolism in either those with risk factors (RR 0.81, p = 0.5) or those without them (RR 0.94, p = 0.8). Haematoma or wound dehiscence was more common in those having chemical prophylaxis (11.9% v 6.9%; RR 1.73 95% CI 1.16 to 2.60). Readmission for symptomatic, radio-logically confirmed thromboembolism involved 1.1% of patients (95% CI 0.55% to 2.1%). Four patients were readmitted with proven non-fatal PE and six with proven DVT (the latest on day 40). Our results show that the main risk factor for thromboembolism was TKR itself; chemical prophylaxis did not reduce the incidence of symptomatic thromboembolism but gave an increased perception of side-effects. New prophylactic methods or combinations of methods are needed, with their efficacy compared by randomised controlled studies of both the clinical and the radiological effect. 相似文献
963.
BACKGROUND AND PURPOSE: This study was designed to determine regional differences and age-related changes in the contribution of ATP-sensitive potassium (KATP) channels to vasodilator responses in the brain stem circulation in vivo. METHODS: Changes in diameter of the basilar artery (baseline diameter, 270 +/- 5 microns [mean +/- SEM]), its large branch (112 +/- 5 microns), and its small branch (49 +/- 2 microns) in response to KATP channel openers levcromakalim and Y-26763 were measured through a cranial window in anesthetized adult (4 to 6 months) and aged (24 to 26 months) Sprague-Dawley rats. RESULTS: Topical application of levcromakalim and Y-26763 produced concentration-dependent vasodilation that was similar among the three vessel groups in adult rats. In aged rats, dilator responses of the branches, but not of the basilar artery, to the KATP channel openers were smaller than those in adult rats (P < .05). Glibenclamide, a selective KATP channel blocker, almost abolished this vasodilation in both groups of rats. Vasodilator responses to sodium nitroprusside were preserved in aged rats. CONCLUSIONS: In adult rats, there is no regional heterogeneity in vasodilator response to KATP channel openers in the brain stem circulation in vivo. In aged rats, although KATP channels are also functional in the brain stem circulation, dilator response of the microvessels but not of the large arteries to direct activation of KATP channels is impaired. 相似文献
964.
JR Daugherty CI Murphy LA Doros-Richert A Barbosa LO Kashala WR Ballou NJ Snellings CF Ockenhouse DE Lanar 《Canadian Metallurgical Quarterly》1997,65(9):3631-3637
The erythrocyte binding antigen EBA-175 is a 175-kDa Plasmodium falciparum protein which mediates merozoite invasion of erythrocytes in a sialic acid-dependent manner. The purpose of this study was to produce recombinant EBA-175 polypeptide domains which have previously been identified as being involved in the interaction of EBA-175 with erythrocytes and to determine whether these polypeptides are recognized by malaria-specific antibodies. The eba-175 gene was cloned by PCR from genomic DNA isolated from the 3D7 strain of P. falciparum. The predicted protein sequence was highly conserved with that predicted from the published eba-175 gene sequences from the Camp and FCR-3 strains of P. falciparum and contained the F segment divergent region. Purified recombinant EBA-175 polypeptide fragments, expressed as glutathione S-transferase fusion proteins in insect cells by using the baculovirus system, were recognized by antibodies present in serum from a drug-cured, malaria-immune Aotus nancymai monkey. The fusion proteins were also recognized by antibodies present in sera from individuals residing in areas where malaria is endemic. In both cases the antibodies specifically recognized the EBA-175 polypeptide portion of the fusion proteins. Antibodies raised in rabbits immunized with the recombinant fusion proteins recognized parasite proteins present in schizont-infected erythrocytes. Our results suggest that these regions of the EBA-175 protein are targets for the immune response against malaria and support their further study as possible vaccine components. 相似文献
965.
JK Brieland LA Heath GB Huffnagle DG Remick MS McClain MC Hurley RK Kunkel JC Fantone C Engleberg 《Canadian Metallurgical Quarterly》1996,157(11):5002-5008
The potential role of humoral immunity in regulating intrapulmonary growth of Legionella pneumophila in the immunocompetent host was investigated using a murine model of Legionnaires' disease. Intratracheal inoculation of A/J mice with a virulent strain of L. pneumophila (10(6) bacteria per mouse) resulted in the recruitment of B lymphocytes into the lung and the development of anti-L. pneumophila Ab. Opsonization of L. pneumophila in vitro with anti-L. pneumophila-specific mAb resulted in a significant decrease in intrapulmonary growth of the bacteria at 24 to 72 h postinfection. Transmission electron microscopic analysis of lung tissue from L. pneumophila- infected mice demonstrated that while there was no significant difference between phagocytosis of the unopsonized and opsonized L. pneumophila by alveolar macrophages at 24 h postinfection, phagocytosis of opsonized bacteria by alveolar mononuclear phagocytic cells was significantly enhanced at 48 h postinfection. Depletion of A/J mice of complement before intratracheal inoculation of opsonized L. pneumophila (10(6) bacteria per mouse) did not significantly alter intrapulmonary growth of L. pneumophila. These results suggest that anti-L. pneumophila Ab, produced during replicative L. pneumophila lung infections, may regulate intrapulmonary growth of L. pneumophila in the immunocompetent host by decreasing the viability of extracellular L. pneumophila and by enhancing phagocytosis of the bacteria by alveolar mononuclear phagocytic cells by a complement-independent mechanism. 相似文献
966.
The cDNA for human galactocerebrosidase (GALC) has recently been cloned and expressed. A portion of this cDNA was used for in situ hybridization, and the region of strongest signal corresponded to human chromosome region 14q31. This agrees with recent linkage studies that localized Krabbe disease (globoid cell leukodystrophy) to the same region. This information will be useful in future studies for mapping this gene in animal models of GALC deficiency. 相似文献
967.
The authors summarize data obtained at the examinations of 178 tuberculous adolescents aged 15-17. Primary forms of the disease were diagnosed in 52% of new-onset cases, while infiltrative tuberculosis prevailed among secondary forms (48%). The tuberculosis was detected at prophylactic fluorography in 63.5% of the examinees. Late disease diagnosis was mostly consequent to poor symptoms of tuberculosis. 相似文献
968.
969.
剌丽俊 《河北机电学院学报》2012,(2):120-122
随着社会老龄化,老年病的防治和医疗保健日益受到重视。老年患者是一个特殊的人群,他们常常存在着脏器功能的退行性改变,导致临床表现症状不典型,因此需要更谨慎的诊治;而且一个患者常常合并多种疾病,要同时服用多种药物,因此还要注意药物的相互作用。 相似文献
970.