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991.
Valve-related complications with the Hancock I porcine bioprosthesis. A twelve- to fourteen-year follow-up study 总被引:4,自引:0,他引:4
J M Bernal J M Rabasa J C Cagigas J R Echevarria M F Carrion J M Revuelta 《The Journal of thoracic and cardiovascular surgery》1991,101(5):871-880
Valve-related morbidity and mortality after heart valve replacement with the Hancock I porcine bioprosthesis has been retrospectively analyzed. From June 1974 through December 1976, 253 Hancock I bioprostheses (150 mitral and 103 aortic) were inserted in 220 selected patients who survived the operation and had follow-up until June 1989 (mean follow-up 13.5 years, with an accumulative follow-up of 2956.4 patient-years). One hundred seventeen patients had mitral valve replacement, 70 had aortic valve replacement, and 33 had combined mitral and aortic valve replacement. There were 27 thromboembolic events. The probability of being free from thromboembolism at 14 years was 81.0% +/- 7.4% for the mitral valve replacement group, 85.4% +/- 6.7% for the aortic group, and 67.1% +/- 18.4% for the mitral-aortic group. Fifteen episodes of prosthetic valve endocarditis occurred. There were 10 instances of nonstructural dysfunction (paravalvular leaks) in seven mitral valves (4.6%) and in three aortic valves (2.9%). One hundred twenty-two bioprostheses in 106 patients resulted in structural deterioration. The probability of freedom from structural deterioration at 14 years was 37.2% +/- 3.9% for the mitral group, 43.9% +/- 7.1% for the aortic group, and 30.1% +/- 8.9% for the mitral-aortic group. The logistic regression analysis between age at the time of operation and bioprosthetic life (structural deterioration-free period) demonstrates a linear regression curve (r = 0.53). There were 56 late deaths (27 patients died at reoperation). The actuarial survival rate (including hospital mortality) at 14 years was 57.2% +/- 5.4% for the entire series, with no statistically significant difference between groups. The probability of remaining free from valve-related morbidity and mortality at 14 years was 16.7% +/- 4.8% for the mitral group, 20.8% +/- 6.2% for the aortic group, and 14.0% +/- 7.0% for the mitral-aortic group. The long-term results of this series show that the clinical performance of the Hancock I porcine valve appears satisfactory during the first 6 years. The behavior of this bioprosthesis at 14 years' follow-up changes drastically, because only a minor group of patients is free from valve-related complications, justifying the restriction of its use for selected patients. 相似文献
992.
Patrick J. Taylor 《Canadian Medical Association journal》1991,145(10):1362-1363
993.
994.
R N Chunge P N Karumba N Nagelkerke N Kaleli M Wamwea N Mutiso E O Andala S N Kinoti 《East African medical journal》1991,68(2):112-123
A cross-sectional survey of intestinal parasitic infection in a rural community, Nderu, in Kiambu District, Kenya, was carried out in 1985 by examining 1129 individuals from 203 households (about 25% of the total population). This was followed by 3 more cross-sectional surveys, in January, May and October 1986, of 56 families comprising 461 individuals, who had also participated in the first survey. In the first survey, 81.4% of the sample was positive for at least one intestinal parasite and 78% was positive for intestinal protozoa. 72.7% of those infected had multiple infections. The prevalence of most of the protozoa increased with age but that of Giardia lamblia peaked in the 0 to 4 year class at 35.5%. Females were infected more often with several of the protozoa, but males with Ascaris. People living in larger households were more often infected with Entamoeba histolytica and Iodamoeba butschlii, while the opposite was true of H. nana and tended to be for Giardia. Significant positive associations between parasite species were common at all surveys, especially among the amoebae. The majority of negative associations were for Giardia. Unformed stools were significantly associated with Giardia, Blastocystis, and trophozoites of Trichomonas hominis and Chilomastix mesnili. Endolimax nana and Entamoeba coli were found more often in formed stools. Estimates of daily incidence, and duration of infection in days, were calculated for 11 parasites. The longest mean estimated duration of infection for any species was 237 +/- S.D. 151.4 days for H. nana and the shortest was 41.6 +/- S.D. 0.4 days for T. hominis. 相似文献
995.
996.
Pediatric procedures in the Emergency Department typically involve techniques for stabilization, evaluation, and treatment of the child. This article considers indications and techniques for vascular access, lumbar puncture, arterial lines, pulse oximetry, and urine collection. Multiple routes of medication administration and pain management modalities also are reviewed. 相似文献
997.
alpha 2-Adrenergic receptors (ARs) are involved in central nervous system (CNS) control of blood pressure. It is now known that there are three human genes that encode subtypes of alpha 2-ARs, but little is known regarding the distribution of these subtypes throughout the CNS. The availability of receptor clones allows the mapping of mRNAs encoding the individual alpha 2-AR subtypes in the CNS. In this communication, we report that there are three, closely related rat alpha 2-AR genes. We have developed subtype-specific hybridization probes from each of these genes and have used these reagents to measure alpha 2-AR subtype mRNA accumulation in extracts of discrete regions of the rat CNS. We found that mRNAs encoding the alpha 2A-AR and alpha 2C-AR subtypes are distributed widely, but unevenly, throughout the rat CNS. The A subtype is prominent in the midbrain, brainstem, spinal cord, pituitary and diencephalon while the C subtype predominates in basal ganglia and cerebellum. The cortex, olfactory bulb and hippocampus contain roughly equal amounts of the alpha 2A- and alpha 2C-AR mRNAs. A third subtype's (alpha 2B-AR) mRNA is far less abundant in brain tissues, and is only found in the diencephalon. 相似文献
998.
999.
Cloning and characterization of Ca(2+)-dependent and Ca(2+)-independent PKCs expressed in Aplysia sensory cells 总被引:2,自引:0,他引:2
K E Kruger W S Sossin T C Sacktor P J Bergold S Beushausen J H Schwartz 《The Journal of neuroscience》1991,11(8):2303-2313
We isolated cDNA clones from an Aplysia sensory-cell library encoding two isoforms of protein kinase C (PKC). Several isozyme-specific regions are conserved in the Aplysia kinases, notably the variable regions V5 in the Ca(2+)-dependent PKC (Apl I) and V1 in the Ca(2+)-independent PKC (Apl II). Neuronal proteins with the properties expected of these two isoforms can be identified with antibodies raised against peptides synthesized from the amino acid sequences deduced from the clones. Sacktor and Schwartz (1990) measured the proportion of kinase activity that can be translocated to membrane in Aplysia sensory neurons and ganglia by stimuli that produce the presynaptic facilitation underlying behavioral sensitization. Much less Apl I and Apl II are translocated, suggesting that still other isoforms of PKC exist in these cells. 相似文献
1000.
The effects of intracellular Ca2+ (Ca2+i) on K+ currents in hippocampal cells were examined using acutely isolated cells obtained from adult guinea pigs. Whole-cell voltage-clamp recordings were carried out in a configuration that allowed a continuous perfusion of the intracellular medium. Recording media were made to block inward currents and allowed selective activation of K(+)-dependent outward currents. Voltage-dependent outward currents consisted of an initial rapidly decaying component followed by a sustained component. The time constant of decay of the transient current was about 25 msec, and previous studies (Numann et al., 1987) showed that the kinetic and pharmacological properties of this current closely resembled the A current recorded in invertebrate neurons (Connor and Stevens, 1971; Thompson, 1982). Intracellular perfusion of hippocampal cells with a solution containing elevated Ca2+ (about 4.5 x 10(-4) M) elicited outward currents at the holding potential (-45 to -55 mV) and produced changes in voltage-dependent K+ currents. The transient outward current (IA) activated by depolarization was suppressed with increases in Ca2+i. Delayed, sustained K+ currents were greatly potentiated. Data also showed that, among the 3 effects elicited by Ca2+i, suppression of IA was most sensitive to Ca2+i elevation. Previous results (Numann et al., 1987) showed that IA had a lower threshold (about -45 mV) than sustained currents (about -40 mV). By using low levels of depolarization (-40 mV), IA can be selectively activated, and the suppressive effect of Ca2+i on IA was confirmed on the kinetically isolated IA.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献