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排序方式: 共有1118条查询结果,搜索用时 15 毫秒
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R A Yeager G L Moneta L M Taylor E J Harris D B McConnell J M Porter 《American journal of surgery》1990,159(5):466-469
A 15-year experience with 38 aortic graft infections, including 15 patients with graft enteric fistulas, is reviewed in order to analyze modern-day surgical results utilizing extra-anatomic bypass and aortic graft excision. Perioperative mortality was 14% during the most recent 7-year interval, which was a notable improvement compared with the earlier time interval (p = 0.06). Extended follow-up of the perioperative survivors demonstrated a 77% cumulative 5-year survival and a 76% cumulative 5-year limb salvage rate. Subsequent axillofemoral graft infection occurred in 22% of survivors and resulted in a significantly higher amputation rate compared with those patients with no axillofemoral graft infection (p less than 0.001). The results suggest good perioperative and long-term survival in patients with aortic graft infection, with excellent limb salvage if subsequent axillofemoral graft infection can be avoided. 相似文献
3.
Transmitter release from presynaptic terminals of electric organ: inhibition by the calcium channel antagonist omega Conus toxin 总被引:3,自引:0,他引:3
R E Yeager D Yoshikami J Rivier L J Cruz G P Miljanich 《The Journal of neuroscience》1987,7(8):2390-2396
Cholinergic synaptosomes from electroplax of the ray Ommata discopyge release both ATP and ACh when depolarized with high K+ concentration in the presence of Ca2+. Others have shown that the ATP and ACh are released in the molar ratio found in isolated synaptic vesicles. Thus, it is assumed that the release of ATP reflects exocytosis of synaptic vesicles, and that transmitter release can be indirectly monitored by assaying ATP release. We present further evidence for this assumption and examine the effects of presynaptic neurotoxins on this ATP release. As expected for transmitter release, we find that depolarization-evoked ATP release is supported by Sr2+ and Ba2+ and is inhibited by the Ca channel antagonists Co2+ and Mn2+. Likewise, the presynaptic toxins omega-CmTX and omega-CgTX, omega peptides from the venom of the marine snails Conus magus and Conus geographus, respectively, inhibit 80% of the depolarization-evoked ATP release. Half-maximal inhibition of ATP release occurs with approximately 0.5 microM of either toxin. The toxins' effects are reversible, and when toxin is washed away, the time dependence of recovery of release is approximately first order and half complete within 40 min with omega-CmTX and 15 min with omega-CgTX. The Ca2+ ionophore A23187 induces Ca2+-dependent ATP release from resting synaptosomes. As would be expected of a Ca channel antagonist, omega-CmTX does not affect this ionophore-induced release. Leptinotarsin-d (LPTd), a putative Ca channel agonist from the Colorado potato beetle, evokes Ca2+-dependent ATP release from resting synaptosomes. omega-CmTX does not block LPTd-evoked release of ATP, which suggests that omega-CmTX and LPTd act at different sites.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Diagnostic significance of immunoglobulin M antibodies to Toxoplasma gondii detected after separation of immunoglobulin M from immunoglobulin G antibodies.
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Failure to demonstrate immunoglobulin M (IgM) antibodies by indirect immunofluorescence (IgM-IFA) in sera from some patients with acute acquired toxoplasmosis has recently been attributed to an inhibitory effect of high titers of IgG antibodies in these sera (Pyndiah et al. J. Clin. Microbiol. 9:170-174, 1979). To confirm these findings and define their importance for diagnosis, we used gel filtration to separate IgM from IgG antibodies in a series of sera that were negative in the IgM-IFA test. A total of 68 sera were from patients with acquired toxoplasmosis, 13 were from uninfected adults, 13 were from infants with congenital toxoplasmosis, and 7 were from uninfected neonates. Of the 68 sera from patients with acquired toxoplasmosis, IgM preparations (from the separated sera) were positive in the IgM-IFA test in 36 (53%). There was a significant (P = 0.00003) association between high titers of IgM-IFA antibodies in the IgM preparations (corrected for dilution of IgM antibodies by the gel filtration procedure) and recent acquisition of infection. IgM antibodies were also detected in 5 (38%) of the IgM preparations of 13 sera from congenitally infected infants but not in any of the IgM preparations of sera from uninfected neonates. IgG antibodies to Toxoplasma gondii were shown to interfere with demonstration of IgM antibodies in the IgM-IFA test. Treatment of sera with protein A resulted in greater dilution of IgM antibodies and less efficient separation of IgM from IgG antibodies than did separation of sera by gel filtration. Treatment of sera with protein A did not result in increased detection of IgM antibodies to T. gondii. Testing of IgM preparations (obtained by gel filtration) resulted in a significant increase in sensitivity of the IgM-IFA test for the diagnosis of recently acquired and congenital toxoplasmosis. 相似文献
5.
Terry?O?Herndon Salvador?Gonzalez TR?Gowrishankar R?Rox?Anderson James?C?WeaverEmail author 《BMC medicine》2004,2(1):12
Background
Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo. 相似文献6.
C S McEnroe T F O'Donnell A Yeager M Konstam W C Mackey 《Journal of vascular surgery》1990,11(4):497-504
Associated coronary artery disease is the critical factor that influences early and late mortality after abdominal aortic aneurysm surgery. Dipyridamole-thallium 201 scintigraphy, left ventricular ejection fraction, and Goldman risk factor analysis have been suggested as preoperative noninvasive screening methods to detect significant coronary artery disease. In this series of 95 elective abdominal aortic aneurysm repairs dipyridamole-thallium 201 scintigraphy was highly predictive of the absence of perioperative cardiac morbidity (96% specificity, 44/46 normal scans, no cardiac morbidity), whereas ejection fraction (73% specificity, 31/42 normal ejection fraction, no cardiac morbidity) and Goldman risk factor analysis (84% specificity, 44/51 class I, no cardiac morbidity) were less. Furthermore, thallium redistribution on dipyridamole-thallium 201 scintigraphy leading to coronary angiography identified a significant number of patients with occult coronary artery disease who required preoperative coronary revascularization (8%, 8/95) and might have remained undetected on the basis of left ventricular ejection fraction or Goldman risk factor analysis. Finally, fixed thallium deficit, which some investigators have interpreted as a low probability finding for cardiac morbidity, was associated with a higher than expected incidence of cardiac complications. Forty-six percent (7/15) of all postoperative cardiac complications (three myocardial infarctions, three ischemic events, one death) occurred in patients with abdominal aortic aneurysms with fixed deficits. This suggests that patients with fixed deficits on dipyridamole-thallium 201 scintigraphy should be considered for later "delayed" (4 hours) thallium images or coronary angiography or both. 相似文献
7.
Eighty four out of 2151 militancy trauma patients sustained severe maxillofacial injury from Jan 1990 to March 1993. The resuscitation, stabilisation and intensive care of these patients was based on management priorities of primary resuscitation, care of airway, management of haemodynamics, oxygenation and monitoring. Anaesthesia was administered in a situation when the airway was likely to be compromised and the patients were critically sick. Initial ventilation and oxygenation was the most difficult and could be achieved with satisfactory seal around the face mask by applying water-soaked guaze pieces around the mouth and nose to “fill-in” the defects. Tracheal intubation could be accomplished with intravenous sedation by an experienced anaesthesiologist. Dental occlusion and wiring necessiated the placement of nasotracheal tube for 48-72 hours after surgery.KEY WORDS: Trauma, Maxillofacial injury, Trauma anesthesia, Anaesthesia and critical care 相似文献
8.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants. 相似文献
9.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
10.
This review of the psychiatric, neuropsychological, and familial contributions to aggressive behavior makes clear that conduct disorder is not a single diagnostic entity. It is, rather, the final common pathway of the interaction among a variety of different kinds of intrinsic vulnerabilities and environmental stressors. In every aggressive child all of these vulnerabilities (none of which necessarily meets full criteria for a specific DSM-IV diagnosis) and stressors must be considered and, if present, addressed systematically. We know that psychotic symptomatology, especially paranoia, combined with neuropsychological vulnerabilities and a history of severe abuse become a recipe for violence, and the more impaired the child, if abused, the more violent the child will become as an adolescent and adult. The clinician must, therefore, think of himself or herself as the only knowledgeable adult who will ever take the time to discover these ingredients and deal with the violent child positively and therapeutically. 相似文献