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21.
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   
22.
Osteomyelitis patients feel their social and professional existence is threatened. Health insurances are faced with total treatment costs for each patient with osteomyelitis, which can reach 500.000,00 EUR. We must therefore make every effort, from the first onset of infection, to prevent the condition from becoming chronic and thus keep the potential problems to patients and insurance companies to a minimum: once the condition has become chronic there is absolutely no guarantee that treatment will be successful. Treatment must start with the removal of absolutely all necrotic tissue – soft tissue and bone – and of all implants. As in tumor surgery, en bloc resection is best. Up to now there is still no means of determining the exact limits of the infection. The surgeons's personal experience with osteomyelitis is the most important factor both in the treatment of these cases and therefore in the containment of treatment costs. Bone reconstruction is attempted after the soft tissue defects have been treated, either by bone grafting (defect < 3 cm) or by segment transfer. Modern techniques of reconstruction surgery can yield quite good results even in chronic oxteomyelitis, providing management has been optimum throughout. Patients with osteomyelitis should therefore be treated in specialist hospitals.  相似文献   
23.
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   
26.
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   
27.
Zusammenfassung Bei Berücksichtigung der physiologischen Variationsbreite lassen sich sowohl hinsichtlich der Differenzierung als auch in Bezug auf die Größe der Handwurzelknochen Normen aufstellen, die eine exakte Grundlage für die Beurteilung des Wachstumsprozesses bilden. Im Gegensatz zu früheren Untersuchungen konnten wesentliche Geschlechtsunterschiede im Ossifikationsverlauf nicht gefunden werden. Die konstitutionellen Varianten sind gering und liegen innerhalb der physiologischen Variationsbreite. Im Vergleich zum Wachstum des Röhrenknochenskeletes ist die Größenzunahme des Handwurzelraumes gering. Für das Schulalter wird die Bedeutung der Größenmessungen betont und dafür in Tabelle 1 Normalzahlen und Schwankungsbreite errechnet. Soweit Vergleiche mit früheren Untersuchungen möglich waren, läßt sich eine gewisse Acceleration des Ossifikationsvurganges feststellen. Asymmetrien im Verlauf der Iernentwicklung deuten auf Störungen hin und liegen außerhalb der physiologischen Variation. In Abb. 4 wurde ein übersichtliches Schema für den praktischen Gebrauch in der Klinik zusammengestellt.  相似文献   
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29.
BACKGROUND: Tumor necrosis factor (TNF)-alpha has pleiotropic effects in cytokine-mediated inflammation underlying atherogenesis. Activation of this inflammatory process is assumed to be different in diabetic and non-diabetic individuals. Previous studies in non-diabetic subjects showed no association between TNF-alpha -308G>A polymorphism and coronary artery disease. METHODS: Vascular complications and cytokine serum concentrations were assessed as a function of the TNF-alpha -308G>A polymorphism in 76 diabetic patients on low-dose aspirin. RESULTS: Of 76 adult diabetic patients, 18 (24%) carried the TNF-alpha -308A allele (17 AG, 1 AA) and 58 (76%) carried wild-type alleles (GG). Prevalence of macrovascular complications was 33% in TNF-alpha -308A allele carriers (AG+AA) and 78% in wild-type allele carriers (GG) (p<0.001). In contrast, prevalence of microvascular complications was 78% and 84%, respectively, and did not significantly differ between the study groups. TNF-alpha -308A allele carriers (AG+AA) compared to wild-type allele carriers (GG) had significantly lower median serum concentrations of hs-C-reactive protein (1.5 vs 2.9 mg/L, p=0.030), interleukin 1-beta (0.9 vs 1.2 ng/L, p=0.046), and interleukin-6 (3.6 vs 4.9 ng/L, p=0.023). In multiple regression analysis, the prevalence of macrovascular diabetic complications was significantly associated with TNF-alpha -308G>A polymorphism (p<0.001) and serum concentrations of HDL-cholesterol (p=0.007) while confounding effects of further variables were excluded. CONCLUSION: TNF-alpha -308G>A polymorphism modulates cytokine serum concentrations and macrovascular complications in diabetic patients on aspirin. Diabetic carriers of the TNF-alpha -308A allele might benefit more from a prophylaxis with low dose aspirin than non-carriers.  相似文献   
30.
 Chromaffin cells of the adrenal medulla and their tumor counterparts, the pheochromocytoma (PC12) cells, are well-established model systems in neurobiology. The development of sympathoadrenal progenitor cells to chromaffin cells can be studied with regard to developmental signals which trigger the differentiation. With regard to potential treatments of neurological disorders like Parkinson’s disease chromaffin cell grafting can be used as one therapeutical approach. The beneficial effect of chromaffin cell grafts is possibly not only related to the release of dopamine but may also be linked to the release of growth factors. One of the growth factors that is synthesized by chromaffin and PC12 cells is basic fibroblast growth factor (FGF-2). The experimental data available so far, are in agreement with different functional roles of FGF-2. This article summarizes the putative physiological functions of FGF-2 in the adrenal medulla. Three differential functional roles of FGF-2 are discussed: (1) as a differentiation factor for sympathoadrenal progenitor cells; (2) as a target-derived neurotrophic factor for preganglionic sympathetic neurons which innervate adrenal medullary cells; (3) as an auto-/paracrine factor in the adrenal medulla. Accepted: 21 August 1996  相似文献   
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