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991.
Recipients of untested blood from donors who at a subsequent donation were positive for HIV antibody by enzyme immunoassay (EIA) were evaluated, whether the result on Western blot (WB) assay was negative (EIA+/WB-) or positive (EIA+/WB+). For 109 EIA+/WB- donors, 78 recipients were tested for HIV antibody, and 3 (4%) were positive. Two of the three anti-HIV-positive recipients had clotting disorders, and the other had been massively transfused; in each of these three cases, subsequent test data exonerated the EIA+/WB- donor. For 101 current EIA+/WB+ donors, 35 recipients were tested for HIV antibody, and 13 (37%) were positive. For donors subsequently found to be EIA+/WB+, the rate of isolation of HIV was the same whether the recipients were anti-HIV-positive or anti-HIV-negative (each, 5/6). While recipients of blood from donors subsequently found to be EIA+/WB+ were at substantial risk for HIV infection, regardless of the donor's subsequent HIV culture result, risk of HIV infection was not demonstrated for recipients of blood from donors later found to be EIA+/WB-. 相似文献
992.
993.
S. C. C. REINDERS FOLMER R. W. KOSTER A. V. LA RIVIÈRE A. J. DUNNING 《European journal of clinical investigation》1983,13(4):325-330
Abstract. Gated equilibrium bloodpool scintigraphy was used to obtain the ratio of left and right ventricular stroke counts (end-diastolic minus end-systolic counts within ventricular areas of interest), the radionuclide equivalent of stroke volumes. This ratio or stroke count index (SCI) should be unity in normal subjects and increased in patients with aortic or mitral regurgitation, when left ventricular stroke output rises to compensate for regurgitant flow. Results of this non-invasive method were compared with semiquantitative angiographic grading of mitral (1 to 4+) or aortic (1 to 3+) regurgitation in ninety-seven patients. We found a SCI of 1.15 ± 0.18 (SD) in thirty-six control subjects without evidence of mitral or aortic regurgitation at cardiac catheterization. Subsequently, a ratio of 1.50 was chosen as the upper limit of normal for the analysis of thirty-seven patients with mitral regurgitation and twenty-four patients with aortic regurgitation. Clearly, elevated SCI values were obtained in the presence of grade 3 and 4 mitral regurgitation (eighteen out of twenty patients) and of grade 2 and 3 aortic regurgitation (seventeen out of eighteen patients). Only two out of seventeen subjects with grade 1 or 2 mitral incompetence had an elevated SCI, while none of six subjects with grade I aortic regurgitation had an abnormal SCI. If these lesser degrees of valvular incompetence are considered of minor significance, overall sensitivity of the radionuclide method in our patient population was 92%, specificity 95%. Occasional discrepancies between SCI and angiographic severity of left-sided valvular regurgitation are probably a result of methodological limitations. We could not demonstrate any relation with global left ventricular function as measured from the radionuclide ejection fraction. We conclude that the SCI may be used as a non-invasive tool for diagnosis and management of patients with valvular heart disease, both before and after interventions. 相似文献
994.
Charlotte S Auth Magdalena T Weidner Sandy Popp Tatyana Strekalova Angelika G Schmitt-Böhrer Daniel LA van den Hove Klaus-Peter Lesch Jonas Waider 《European neuropsychopharmacology》2018,28(11):1270-1283
Anxiety disorders represent one of the most prevalent mental disorders in today's society and early adversity has been identified as major contributor to anxiety-related pathologies. Serotonin (5-hydroxytryptamine, 5-HT) is implicated in mediating the effects of early-life events on anxiety-like behaviours. In order to further elucidate the interaction of genetic predisposition and adversity in early, developmental stages on anxiety-related behaviours, the current study employed tryptophan hydroxylase 2 (Tph2)–deficient female mice, as a model for lifelong brain 5-HT synthesis deficiency. Offspring of this line were exposed to maternal separation (MS) and tested, in the open-field (OF) or the dark-light box (DLB). Subsequently, neural activity was assessed, using c-Fos immunohistochemistry. In the DLB, MS rescued the observed decrease in activity in the light compartment of homozygous Tph2–deficient mice and furthermore increased the incidence of escape-related jumps in animals of the same genotype. In the OF, MS increased escape-related behaviours in homo- and heterozygous Tph2-deficient offspring. On the neural level, both behavioural tests evoked a distinct activation pattern, as shown by c-Fos immunohistochemistry. Exposure to the DLB resulted in Tph2-dependent activation of paraventricular nucleus and basolateral amygdala, while OF exposure led to a specific activation in lateral amygdala of maternally separated animals and a Tph2 genotype- and MS-dependent activation of the ventrolateral and dorsolateral periaqueductal grey. Taken together, our findings suggest that MS promotes active responses to aversive stimuli, dependent on the availability of brain 5-HT. These effects might be mediated by the distinct activation of anxiety-relevant brain regions, due to the behavioural testing. 相似文献
995.
Atrial Rate‐Responsive Pacing and Incidence of Sustained Atrial Arrhythmias in Patients with Implantable Cardioverter Defibrillators 下载免费PDF全文
ADOLFO FONTENLA M.D. Ph.D. RAFAEL SALGUERO M.D. JOSE B. MARTINEZ‐FERRER M.D. ANIBAL RODRIGUEZ M.D. JAVIER ALZUETA M.D. Ph.D. ENRIQUE GARCIA M.D. NURIA BASTERRA M.D. RAFAEL ROMERO M.D. JOAQUIN FERNANDEZ DE LA CONCHA M.D. XAVIER VIÑOLAS M.D. Ph.D. JULIAN VILLACASTIN M.D. Ph.D. MARIA LOPEZ‐GIL M.D. FERNANDO ARRIBAS M.D. Ph.D. 《Pacing and clinical electrophysiology : PACE》2016,39(6):548-556
996.
Huang Li Lester A. H. Critchley Jie Zhang 《Journal of clinical monitoring and computing》2016,30(5):559-567
The demise of the pulmonary artery catheter as a gold standard in cardiac output measurement has created the need for new standard. Doppler cardiac output can be measured suprasternally (USCOM) and via the oesophagus (CardioQ). Use in tandem they may provide a reliable trend line of cardiac output changes against which new technologies can be assessed. Data from three similar clinical studies was pooled. Simultaneous USCOM and CardioQ readings, 13 (7–27), were performed every 15–30 min intraoperatively. Within individual patient regression analysis was performed. Data was normalized, CardioQ against USCOM, to eliminate the systematic error component following calibration. Bland–Altman and trend, concordance and polar analysis, were performed on the grouped data. Cardiac output was indexed (CI) to BSA. Data from 53 patients, aged 59 (26–81) years, scheduled for major surgery were included. Within-individual mean (SD) CI was 3.4 (0.6) L min?1 m?2. Correlation was good to excellent in 83 % of cases, R2 > 0.80, and reasonable in 96 %, R2 > 0.60. Percentage error was 38 %, and decreased to 14 % with normalization. The estimated 95 % precision for a single Doppler reading was ±10 %. Concordance rate was 96.6 % (confidence intervals 94.7–99.5 %) and above the >92 % threshold for good trending ability. Polar analysis also confirmed good trending ability. The regression line between Doppler methods was offset with a slope of 0.9, thus CardioQ CI readings increased relative to USCOM. Both Doppler methods trended cardiac output reliably. Used in tandem they provide a new standard to assess cardiac output trending. 相似文献
997.
Evolutionary conservation of surface molecules that distinguish T lymphocyte helper/inducer and cytotoxic/suppressor subpopulations in mouse and man 总被引:70,自引:23,他引:70 下载免费PDF全文
JA Ledbetter RL Evans M Lipinski C Cummingham-Rundles RA Good LA Herzenberg 《The Journal of experimental medicine》1981,153(2):310-323
We describe the biochemical properties and cell surface distributions of three human T cell antigens (Leu-1, Leu-2a, and Leu-2b) which we postulate to be the homologues of the Lyt-1, Lyt-2, and Lyt-3 antigens that distinguish functional T cell subsets in the mouse. Leu-l, like Lyt-1, is on all thymocytes and peripheral T cells and is present in greater amounts on the helper/inducer subset than on the cytotoxic/suppressor subset. Both antigens increase in parallel fashion during T cell maturation in the thymus and each antigen is carried on a single 67,000-molecular weight (relative) (M(r)) polypeptide chain. Surprisingly, Leu-1 and Lyt-1 each are also expressed in readily detectable amounts on some B celI Ieukemias but not detectably so on normal B cells. Leu-2a and Leu-2b are antigens found only on suppressor/cytotoxic cells in the human and are very similar to the murine Lyt-2 and Lyt-3 antigens. In both species, the two antigens are on the same disulfide- linked multimeric molecules. Disulfide-bond reduction in both species yields subunits of similar size and charge. Lyt-3 and Leu-2b are extremely sensitive to trypsin digestion on viable cells whereas Lyt-2 and Leu-2a are much less so. A different membrane antigen, Leu-3, is an exclusive marker of the helper/inducer subset in man. No mouse homologue for this 55,000-M(r) protein is known. The maintenance of the homologous molecules on functionally distinct T cell subpopulations in two evolutionarily distant species suggests that the Lyt and Leu antigens perform essential functions for the cells on which they are found. 相似文献
998.
999.
目的:研究滋肾清肝代平方对实验性2型糖尿病(T2DM)大鼠血糖、血脂和胰岛素敏感性的影响。方法:大鼠高糖高脂饲料喂养4周后,腹腔注射30 mg·kg-1链脲佐菌素建立T2DM大鼠模型,随机分为糖尿病模型对照组、滋肾清肝代平方低剂量组(灌胃400 mg·kg-1·d-1)、中剂量组(灌胃800 mg·kg-1·d-1)、高剂量组(灌胃1200 mg·kg-1·d-1)及罗格列酮治疗组(灌胃4 mg·kg-1·d-1)。以滋肾清肝代平方低、中、高剂量持续给药30 d后测空腹血糖(FBG)、血脂、糖化血红蛋白(HbAlc)、胰岛素(Ins)的含量及口服糖耐量实验。结果:与模型组比较,滋肾清肝代平方可显著降低T2DM模型大鼠的FBG、HbAlc、甘油三酯(TG)、总胆固醇(TC)及低密度脂蛋白(LDL)及糖耐量实验(OGTT)中糖负荷后120 min血糖水平(P<0.05),显著升高高密度脂蛋白(HDL)和Ins、胰岛素敏感指数(ISI)水平(P<0.05)。结论:滋肾清肝代平方能有效地降低T2DM模型大鼠的血糖,增加胰岛素敏感性,纠正脂代谢紊乱,调节血脂。 相似文献
1000.
Munro MG Broder M Critchley HO Matteson K Haththotuwa R Fraser IS 《Seminars in reproductive medicine》2011,29(5):436-445
More than 600 registrants attended a two-hour interactive symposium on abnormal uterine bleeding (AUB) at the Federation of Gynecology and Obstetrics World Congress in Cape Town, October 2009. Nearly 250 of these participants answered multiple questions through an electronic audience responder system. The audience heard five structured presentations on clinically important and controversial aspects of AUB, including terminologies and definitions, classification of causes, mechanisms of AUB in the absence of structural lesions of the reproductive tract, the potential for a structured menstrual history, and management of heavy menstrual bleeding (HMB) in low-resource settings. Numerous demographic details were collected, and a total of 30 questions to the audience were interspersed through each of the presentations. The audience demonstrated great variation in the way the terms AUB, menorrhagia, and dysfunctional uterine bleeding (DUB) are used, and considerable majorities agreed that the terms menorrhagia and DUB should be abolished. AUB should be the overarching term to describe all symptomatic departures from normal menstruation or the menstrual cycle. HMB is a suitable replacement term for menorrhagia. DUB can be replaced by the three clinical entities comprising "nonstructural" causes of AUB. There was a high consistency across demographic subgroups in answers to most questions. Acute and chronic AUB were defined, and aspects of a classification system for causes of AUB and of a structured menstrual history were explored. Issues related to investigation and hormonal treatment of HMB in low-resource settings were explored by registrants from developing countries. 相似文献