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The ability of human immunodeficiency virus type-1 (HIV-1) and recombinant HIV-1 gp120 to prevent target cell lysis by herpes simplex virus type 1 (HSV-1)-specific cytotoxic T lymphocytes (CTL) was assessed by limiting dilution analysis. Live and inactivated HIV-1 as well as recombinant-derived gp120 all substantially inhibited HSV-1-specific CTL. Soluble CD4 antigen reversed the inhibition by gp120 when simultaneously added with gp120 to the assay. In addition, the monoclonal anti-CD4 antibody a-Leu3a mimicked the effects of gp120 in these experiments. These data suggest that the observed decrease in measurable CTL activity is caused by direct or steric hindrance of the CD4-class II major histocompatibility complex interaction between the effector and target cells.  相似文献   
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AIMS: Characterizing the time course of the rise of blood glucose concentrations in the fasting state during the day and night in patients with type 2 diabetes. METHODS: 40 consecutive insulin-treated patients with type 2 diabetes underwent fasting tests on two different days with either no breakfast and lunch (fasting time of 20 hours) or no dinner (fasting time of 21 hours). Glucose-lowering medication was stopped prior to the test according to the half-life of the medication prescribed. At the start of the fasting tests, blood glucose concentrations were lowered to below 7 mmol/L using an insulin infusion. RESULTS: 26 men and 14 women were included in the study. Mean (+/-SD) age was 61+/-10 years, BMI 31+/-7 kg/m (2), and HbA1c 7.5+/-1%. Diabetes duration was 14+/-8 years and duration of insulin therapy had been prescribed for a mean of 6+/-6 years. During the daytime fast, plasma glucose concentrations rose by a mean of 0.8+/-1.6 mmol/L. During the nighttime fast, plasma glucose concentrations increased particularly after midnight, by 4.3+/-2.1 mmol/L, i.e. significantly more than during the daytime fast. CONCLUSIONS: Fasting blood glucose concentrations in the majority of insulin-treated patients with type 2 diabetes increase markedly after midnight. No similar increase is observed during the day. Thus, for most patients with type 2 diabetes, an intermediate- or long-acting insulin injected at bedtime with a peak action six to eight hours after injection should be appropriate.  相似文献   
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We report on an unusual case of a young female patient who received an implantable LVAD after unsuccessful emergency coronary bypass surgery following acute myocardial infarction. After LVAD placement, it became evident that the patient had been pregnant. She had to undergo gynaecological surgery during mechanical support to remove the deceased fetus.  相似文献   
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Purpose: Caucasian children with myopia have elevated response accommodative vergence to accommodation (AC/A) ratios. The purpose of this study was twofold: to determine if response AC/A ratios vary with refractive error and with myopic progression rate in Hong Kong Chinese children, and to determine the effect of beta‐adrenergic antagonism with topical timolol application on AC/A ratios. Methods: Thirty children aged eight to 12 years participated in the study. All refractive errors were corrected with spectacle lenses. Accommodative responses were measured using a Shin‐Nippon autorefractor and concurrent changes in vergence were assessed using a vertical prism and a Howell‐Dwyer card at three metres and 0.33 metre. Accommodative demand was altered using plus or minus two dioptre lenses and lens‐ and distance‐induced response AC/A ratios were calculated. Measurements were repeated 30 minutes after the instillation of topical timolol maleate (0.5 per cent). Results: AC/A ratios appeared higher in progressing myopic children but the difference was not statistically significant. Timolol application reduced accommodative convergence (AC) in the stable myopes (reduction = ‐3 ± 1.14A) but not in the emmetropes (0.69 ± 0.9P) or progressing myopes (0.16 ± 0.43A) and this difference between refractive groups was statistically s ignificant (F2,27= 3.766; P= 0.036). However, timolol did not produce a significant change in the accommodative response to positive or negative lenses or response AC/A ratios. Conclusions: We did not find that AC/A ratios in myopic Chinese children were elevated and therefore, it is unlikely that elevated AC/A ratios are responsible for the high levels of myopia that occur in Hong Kong. The finding that timolol reduced AC in the stable myopes suggests that the autonomic control of accommodative convergence in these children may be different from that in emmetropic children and those with progressing myopia.  相似文献   
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