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91.
MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献
92.
93.
本研究在于确定胃酸抑制剂是否会增加选择性手术患者术后发生肺炎的风险。
此项人群前瞻性队列研究于1992年4月1日-2008年3月31日在加拿大开展。年龄大于65岁已确定进行选择性手术的患者入组。将本年度在手术前服用过两种或以上胃酸抑制剂的患者以及术前90天内服用过至少一种胃酸抑制剂的患者入试验组, 相似文献
94.
Derwall M Francis RC Kida K Bougaki M Crimi E Adrie C Zapol WM Ichinose F 《Critical care (London, England)》2011,15(1):R51
Introduction
Although inhalation of 80 parts per million (ppm) of hydrogen sulfide (H2S) reduces metabolism in mice, doses higher than 200 ppm of H2S were required to depress metabolism in rats. We therefore hypothesized that higher concentrations of H2S are required to reduce metabolism in larger mammals and humans. To avoid the potential pulmonary toxicity of H2S inhalation at high concentrations, we investigated whether administering H2S via ventilation of an extracorporeal membrane lung (ECML) would provide means to manipulate the metabolic rate in sheep. 相似文献95.
Pramana IA Latzin P Schlapbach LJ Hafen G Kuehni CE Nelle M Riedel T Frey U 《European journal of medical research》2011,16(5):223-230
Objective
While respiratory symptoms in the first year of life are relatively well described for term infants, data for preterm infants are scarce. We aimed to describe the burden of respiratory disease in a group of preterm infants with and without bronchopulmonary dysplasia (BPD) and to assess the association of respiratory symptoms with perinatal, genetic and environmental risk factors.Methods
Single centre birth cohort study: prospective recording of perinatal risk factors and retrospective assessment of respiratory symptoms during the first year of life by standardised questionnaires. Main outcome measures: Cough and wheeze (common symptoms), re-hospitalisation and need for inhalation therapy (severe outcomes). Patients: 126 preterms (median gestational age 28.7 weeks; 78 with, 48 without BPD) hospitalised at the University Children''s Hospital of Bern, Switzerland 1999-2006.Results
Cough occurred in 80%, wheeze in 44%, rehospitalisation in 25% and long term inhalation therapy in wheezers in 13% of the preterm infants. Using logistic regression, the main risk factor for common symptoms was frequent contact with other children. Severe outcomes were associated with maximal peak inspiratory pressure, arterial cord blood pH, APGAR and CRIB-Score.Conclusions
Cough in preterm infants is as common as in term infants, whereas wheeze, inhalation therapy and re-hospitalisations occur more often. Severe outcomes are associated with perinatal risk factors. Preterm infants who did not qualify for BPD according to latest guidelines also showed a significant burden of respiratory disease in the first year of life. 相似文献96.
Short-term oestradiol treatment modulates hippocampus-dependent memory and synaptic plasticity in the hippocampus. Long-term oestradiol treatment can also enhance hippocampus- dependent memory, although the effects of long-term oestradiol treatment on synaptic plasticity are unknown. We investigated the effects of long-term oestradiol treatment on synaptic plasticity at the Schaeffer Collateral/CA1 synapse in 8-month-old female rats. In addition, we determined the role of endogenous activation of muscarinic acetylcholine receptors (mAChRs) in synaptic transmission and plasticity using scopolamine (1 μm), an antagonist of mAChRs. Hippocampus slices from ovariectomised rats that were treated with oestradiol-containing capsules for 5 months were compared with slices from ovariectomised rats that received cholesterol-containing capsules. Unexpectedly, scopolamine application significantly increased the baseline field excitatory postsynaptic potentials (fEPSP) and decreased paired pulse facilitation (PPF) in slices from cholesterol-treated rats. Baseline fEPSPs and PPF were not significantly modulated in slices from oestradiol-treated rats by scopolamine. Slices from oestradiol-treated rats showed enhanced long-term potentiation relative to slices from cholesterol-treated rats. Scopolamine significantly reduced the magnitude of plasticity in slices from oestradiol-treated rats. Taken together, these results suggest that mAChRs have a significant effect on baseline synaptic transmission through a decrease in the probability of glutamate release in slices from cholesterol-treated rats. Long-term oestradiol treatment blocks this effect and enhances theta-burst stimulation-induced synaptic plasticity in the middle-aged female rat, and this effect is mediated by activation of mAChRs. 相似文献
97.
98.
CE Rubin 《Gastroenterology》1997,112(6):2108-2110
This article has no abstract. To view the article, select the "View Print Version (PDF)" link above. 相似文献
99.
100.
目的:探讨磁共振氢质子谱(1H-MRS)对原发性单侧起病帕金森病的诊断价值。方法:未经治疗的原发单侧症状PD患者50例为PD组,健康人42名为对照组。两组分别予以双侧壳核MRS检查,由仪器自带软件自动计算得双侧壳核代谢物比值:NAA/Cr,Cho/Cr,NAA/Cho。结果:PD组患者其症状对侧壳核NAA/cr比值分别较同侧及健康对照组双侧壳核相应比值均值明显下降(分别为1.23±0.22,1.38±0.33,1.33±0.16;t=2.616,P=0.01和t=2.324,P=0.02),而其NAA/Cho、Cho/Cr比值较同侧及对照组相应比值均值无显著差异。症状同侧壳核NAA/cr、NAA/Cho、Cho/Cr较对照组无明显差异。结论:原发性单侧症状PD其症状的对侧壳核早期就可能存在神经元的缺失或胶质增生,提示壳核磁共振波谱分析可为早期PD的临床诊断提供较为可靠的客观依据。 相似文献