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71.
Human immunodeficiency virus (HIV) has been isolated from plasma in 6 of 7 patients showing clinical symptoms of a primary HIV infection. Parallel cultures from peripheral blood mononuclear cells (PBMC) yielded virus in 5 patients. In one case, virus could only be isolated from the cerebrospinal fluid but not from peripheral blood. Detectable viremia was transient and preceded the appearance of HIV specific antibodies. After cessation of acute symptoms, the frequency of HIV isolations was similar to that of asymptomatic carriers (23 and 26%, respectively). The role of the immune response in terminating detectable viremia remains to be established.  相似文献   
72.

Background  

Previous publications indicate that acupuncture is efficient for the treatment of pelvic girdle pain, PGP, in pregnant women. However, the use of acupuncture for PGP is rare due to insufficient documentation of adverse effects of this treatment in this specific condition. The aim of the present work was to assess adverse effects of acupuncture on the pregnancy, mother, delivery and the fetus/neonate in comparison with women that received stabilising exercises as adjunct to standard treatment or standard treatment alone.  相似文献   
73.
The pitch identification performance of absolute pitch possessors has previously been shown to depend on pitch range, key color, and timbre of presented tones. In the present study, the dependence of pitch identification performance on key color and timbre of musical tones was examined by analyzing hit rates, reaction times, and pupillary responses of absolute pitch possessors (n = 9) and nonpossessors (n = 12) during a pitch identification task. Results revealed a significant dependence of pitch identification hit rate but not reaction time on timbre and key color in both groups. Among absolute pitch possessors, peak dilation of the pupil was significantly dependent on key color whereas the effect of timbre was marginally significant. Peak dilation of the pupil differed significantly between absolute pitch possessors and nonpossessors. The observed effects point to the importance of learning factors in the acquisition of absolute pitch.  相似文献   
74.
Limiting dilution analysis has been used in the context of allogeneic bone marrow transplantation to determine anti-recipient interleukin-2 (IL-2) producing helper T lymphocyte precursor (HTLp) frequencies, which in several studies have been predictive of graft-versus-host disease (GVHD). Recently high anti-recipient IL-4 producing HTLp frequencies have been reported and associated with a decreased risk of GVHD. The aim of the present study was to define the optimal conditions for combined determination of IL-2 and IL-4 producing anti-recipient HTLp frequencies. We have optimised the CT.h4S bioassay with regards to specificity, sensitivity, detection limit, and reproducibility. We have found the optimal assay conditions to be 1 x 10 (4) CT.h4S cells/well deprived of IL-4 for 24 h and preincubated for 7 h followed by 18 h of incubation with tritiated methyl-thymidine. In this setting the CT.h4S bioassay detects 5 pg/ml of human recombinant IL-4 with no detection of IL-2 in concentrations below 500 pg/ml. We have found 72 h of culture optimal for detection of IL-2 and IL-4 produced by human mononuclear cells (MNC) in response to stimulation with phytohaemaglutinin and for detection of IL-2 in human leukocyte antigen (HLA)-mismatched mixed leukocyte culture (MLC). An interindividual variation in cytokine accumulation was demonstrated for IL-4 but not for IL-2. With the use of 5x10(4) responder cells/well no IL-4 could be detected in HLA-mismatched MLC between days 1 and 16. The lack of IL-4 detection was not due to high amounts of soluble IL-4 receptor. With the use of 1x10(6) responder cells/well in HLA-mismatched MLC, we found limited IL-4 accumulation still increasing at day 12. We conclude that the CT.h4S bioassay is a reliable and specific method for quantification of IL-4 accumulation in cultures of human MNC. The difference in optimal timing for IL-2 (day 3) and IL-4 (>/=day 12) detection and evidence of very low IL-4 producing HTLp frequencies makes the relevance of a combined IL-2/IL-4 HTLp assay questionable.  相似文献   
75.
In whole muscle homogenates, the glucose transporter-4 (GLUT-4) content is reported to be higher in muscles consisting predominantly of oxidative (type-1) muscle fibres than in muscles consisting predominantly of glycolytic (type-2) fibres. From these findings, it has been deduced that in rat muscle, oxidative fibres have an intrinsically higher level of GLUT-4 protein than glycolytic fibres. No data is available concerning human muscle. Moreover, the fibre-type-specific expression of GLUT-4 has not yet been examined directly. In this study, the relative abundance of GLUT-4 protein expression in individual fibres of different types within a muscle was compared directly in immunohistochemical assays. The human vastus lateralis muscle and a selection of rat muscles were studied using a novel GLUT-4 antiserum. It is concluded that the pattern of fibre-type-specific GLUT-4 expression differs between human and rats and varies between the different muscles studied, indicating that non-fibre-type-specific factor(s) affect expression of GLUT-4. The observation that within a muscle a fibre-type-specific expression of GLUT-4 was observed indicates that fibre-type-specific factors contribute to GLUT-4 expression as well. Thus, it can be postulated that both fibre-type-dependent and fibre-type-independent factors affect GLUT-4 expression.  相似文献   
76.
The response of isolated brain vessels to various pH levels or carbon dioxide tensions was analyzed. Reduction of the pH induced a slight relaxation of the vessel, whereas an increase in the pH produced a slight contraction. These effects were markedly exaggerated when the alpha-adrenergic receptors in the vascular wall were activated by noradrenaline. During these conditions the contractile response to noradrenaline was reduced by about 40 per cent at a pH of 7.01, while, on the other hand, the response was enhanced 3-fold at a pH of 7.80. Variations in carbon dioxide tension of the buffer solution between 16 mmHg and 64 mmHg produced no consistent change, provided the pH remained constant. The results indicate that an interaction between the perivascular pH and the adrenergic alpha-receptor mediated contraction in brain vessels may occur.  相似文献   
77.
78.
79.
Glycaemic control in type 2 diabetic patients varies widely between general practitioners (GPs). To increase our understanding of this variation, linear random effects models were used to examine the predictive value of GP characteristics on the course of annual HbA1c measurements, in 688 newly diagnosed type 2 diabetic patients between one and five years after diabetes diagnosis. We found that characteristics of centrally supported GPs, such as interest in diabetes, experience, practice type, list size, and weekly working hours, did not predict their patients' glycaemic control.  相似文献   
80.
Voltage- and Ca(2+)-dependent K(+) channels in the membrane of both T and B lymphocytes are important for the cellular immune response. In the current issue of the European Journal of Immunology, Reich et al. demonstrate that selective blockade of the intermediate-conductance Ca(2+)-activated K(+) channel (the IK channel encoded by the KCNN4 gene) prevents cytokine production in the spinal chord and ameliorates the development of EAE caused by injection of myelin oligodendrocyte glycoprotein (MOG)(35-55) in mice. These data renew the focus on the IK channel as a potential target for the development of new immune-suppressant drugs for the treatment of autoimmune diseases.  相似文献   
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