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91.
92.
Analysis of deaths in patients awaiting heart transplantation: impact on patient selection criteria. 总被引:1,自引:0,他引:1 下载免费PDF全文
G. A. Haywood P. R. Rickenbacher P. T. Trindade L. Gullestad J. P. Jiang J. S. Schroeder R. Vagelos P. Oyer M. B. Fowler 《Heart (British Cardiac Society)》1996,75(5):455-462
OBJECTIVE: To analyse the clinical characteristics of patients who died on the Stanford heart transplant waiting list and to develop a method for risk stratifying status 2 patients (outpatients). METHODS: Data were reviewed from all patients over 18 years, excluding retransplants, who were accepted for heart transplantation over an eight year period from 1986 to 1994. RESULTS: 548 patients were accepted for heart transplantation; 53 died on the waiting list, and 52 survived on the waiting list for over one year. On multivariate analysis only peak oxygen consumption (peak VO2: 11.7 (SD 2.7) v 15.1 (5.2) ml/kg/min, P = 0.02) and cardiac output (3.97 (1.03) v 4.79 (1.06) litres/min, P = 0.04) were found to be independent prognostic risk factors. Peak VO2 and cardiac index (CI) were then analysed in the last 141 consecutive patients accepted for cardiac transplantation. All deaths and 88% of the deteriorations to status 1 on the waiting list occurred in patients with either a CI < 2.0 or a VO2 < 12. In those with a CI < 2.0 and a VO2 < 12, 38% died or deteriorated to status 1 in the first year on the waiting list. Patients with CI > or = 2.0 and a VO2 > or = 12 all survived throughout follow up. Using a Cox's proportional hazards model with CI and peak VO2 as covariates, tables were constructed predicting the chance of surviving for (a) 60 days and (b) 1 year on the waiting list. CONCLUSIONS: These data provide a basis for risk stratification of status 2 patients on the heart transplant waiting list. 相似文献
93.
94.
Characterization of adhesive interactions between human endothelial cells and megakaryocytes. 总被引:3,自引:0,他引:3 下载免费PDF全文
H Avraham S Cowley S Y Chi S Jiang J E Groopman 《The Journal of clinical investigation》1993,91(6):2378-2384
Cell-cell adhesion is essential for many immunological functions and is believed to be important in the regulation of hematopoiesis. Adhesive interactions between human endothelial cells and megakaryocytes were characterized in vitro using the CMK megakaryocytic cell line as well as marrow megakaryocytes. Although there was no adhesion between unactivated human umbilical vein endothelial cells (HUVEC) and megakaryocytes, treatment of HUVEC with inflammatory cytokines such as IL-1 beta, tumor necrosis factor alpha, INF-gamma, or the phorbol ester phorbol myristate acetate (PMA) resulted in a time- and dose-dependent increase in adhesion. Stimulation of marrow megakaryocytes or CMK cells with the cytokines IL-1 beta, GM-CSF, IL-6, IL-3, or PMA augmented their adhesion to endothelium. Monoclonal antibodies against the LFA-1 subunit of the leukocyte adherence complex CD18 inhibited the binding of marrow megakaryocytes or CMK cells to HUVEC. Adhesion blocking experiments also demonstrated that the VLA-4/VCAM-1 pathway was important for megakaryocyte attachment to HUVEC. Adhesion promoted maturation of megakaryocytic cells as measured by increased expression of glycoproteins GpIb and GpIIb/IIIa and by increased DNA content. These observations suggest that alterations in megakaryocyte adhesion may occur during inflammatory conditions, mediated by certain cytokines, resulting in augmented megakaryocyte maturation. 相似文献
95.
本研究主要对El Tor型霍乱弧菌(Vibrio cholerae biotvpe eltor,EVC)L型的某些生物学特性如生化反应、抗生素敏感性及超微结构等进行了探讨.研究发现EVC不稳定L型的生化性状与EVC流行株的非常相似,而稳定L型则变化很大.抗生素敏感性试验显示EVC稳定L型对某些作用于细胞壁的抗生素的敏感性减弱,而对大多数作用于蛋白质合成的抗生素的敏感性增强.与流行株相比,EVC稳定L型和不稳定L型的超微结构的改变很明显.此外,本文还讨论了产生这些改变的可能机制. 相似文献
96.
原发性干燥综合征与人类组织相容性抗原—DRβ基因 总被引:1,自引:0,他引:1
原发性干燥综合征(PSS)的病因未明,其中可能涉及遗传因素。用序列特异性引物聚合酶链反应(PCR-SSP)法对70例PSS患者和136名正常人进行人类组织相容性抗原(HLA)-DRβ基因分型。发现PSS患者群体的HLA-DR3、DR52及DR2的基因频率明显高于正常对照组,而HLA-DR5及DR9的基因频率则相反,提示PSS的发病与DR3、DR52及DR2呈正相关;而和DR9、DR5呈负相关。2个PSS患者家族的姐妹与患者具有相同的遗传因素,且和PSS患者群体测定的正相关基因相一致。PSS患者的主要自身抗体(抗SSA抗体及抗SSB抗体)与HLA-DR52之间有明显的相关性,因而表明PSS的发病和遗传因素有关。 相似文献
97.
Population toxicokinetics of tetrachloroethylene 总被引:1,自引:0,他引:1
F. Y. Bois A. Gelman J. Jiang D. R. Maszle L. Zeise G. Alexeef 《Archives of toxicology》1996,70(6):347-355
In assessing the distribution and metabolism of toxic compounds in the body, measurements are not always feasible for ethical
or technical reasons. Computer modeling offers a reasonable alternative, but the variability and complexity of biological
systems pose unique challenges in model building and adjustment. Recent tools from population pharmacokinetics, Bayesian statistical
inference, and physiological modeling can be brought together to solve these problems. As an example, we modeled the distribution
and metabolism of tetrachloroethylene (PERC) in humans. We derive statistical distributions for the parameters of a physiological
model of PERC, on the basis of data from Monster et al. (1979). The model adequately fits both prior physiological information
and experimental data. An estimate of the relationship between PERC exposure and fraction metabolized is obtained. Our median
population estimate for the fraction of inhaled tetrachloroethylene that is metabolized, at exposure levels exceeding current
occupational standards, is 1.5% [95% confidence interval (0.52%, 4.1%)]. At levels approaching ambient inhalation exposure
(0.001 ppm), the median estimate of the fraction metabolized is much higher, at 36% [95% confidence interval (15%, 58%)].
This disproportionality should be taken into account when deriving safe exposure limits for tetrachloroethylene and deserves
to be verified by further experiments.
Received: 20 April 1995/Accepted: 24 August 1995 相似文献
98.
99.
环丙沙星与氧氟沙星注射液治疗细菌性感染的疗效观察 总被引:3,自引:0,他引:3
以乳酸环丙沙星(CPLX)注射液和氧氟沙星(OFLX)注射液随机分组治疗各种细菌性感染40例及42例,并以注射用头孢噻肟钠(CTX)治疗49例作对照。三组平均年龄、体重、疗程及病情程度相比无显著性差异,具可比性。病种分布以消化道感染最多,共81例,占总数的61.8%。三组131例病人细菌阳性率为94.7%。一疗程CPLX组、OFLX组、CTX组治愈率分别为87.2%、83.3%、71.4%,有效率 相似文献
100.
颈椎后纵韧带骨化的治疗方法 总被引:5,自引:2,他引:3
从1983年8月至1991年3月,手术治疗63例颈韧后纵韧带骨化(OPLL)的患者。手术方法包括前路椎间减压融合,椎体次全切除植骨融合、后路全椎板切除。单开门椎板成形椎管扩大手术、双开门椎板成形椎管扩大手术,及前后路两次手术。随诊6到96个月,疗效为39例代。16例良,优良率87.2%。本文讨论了前路椎间减压、椎体次全切除及后路椎板成形椎管扩大手术的方法。作者认为对OPLL伴广泛性椎管狭窄者以后路双开门椎板成形椎管扩大手术较为合理。 相似文献