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81.
Persson K Haidl S 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(2):131-138
A commercial test (rELISA) based on a recombinant chlamydial lipopolysaccharide (LPS) antigen has been evaluated for the diagnosis of acute infections caused by Chlamydia pneumoniae (TWAR) and Chlamydia psittaci. This test and a microimmunofluorescence test (MIF) were compared in 160 patients with community-acquired pneumonia. Seventeen of nineteen cases with significant titre changes detected by rELISA were confirmed by MIF. The two remaining cases not confirmed by MIF were considered false-positive reactions. One case positive by MIF only was judged not to be a true-positive reaction. All three cases occurred in patients with Mycoplasma pneumoniae infection and may be the result of a mitogenic effect. High antibody titres have been used to indicate acute C. pneumoniae infection. We found high MIF or rELISA titres to be equally common in patients and controls; no association between the two tests was detected. An unexpected cross-reactivity between the rELISA antigen and parvovirus was observed, which might have diagnostic implications. Both MIF and rELISA detected acute C. pneumoniae and C. psittaci infection, and there was good agreement between the tests. Single serum diagnosis was generally not feasible with either MIF or rELISA. 相似文献
82.
P H Larsson J Hed S G Johansson U Persson M Wahlstr?m 《Journal of immunological methods》1989,116(2):293-298
A method for the chemical modification of plastic surfaces permits covalent binding of proteins and we have used this method in the development of an efficient panning technique. Thus, human peripheral T lymphocytes coated with mouse monoclonal antibodies directed against the CD4 marker may be selectively and reproducibly removed from a lymphocyte population by a short incubation in modified plastic dishes coated with rabbit anti-mouse IgG antibody. Due to the higher protein binding capacity of the dishes the use of the IgG fraction of the coating antibody was sufficient for optimal and reproducible results. In contrast, control dishes with passively adsorbed antibody required an affinity-purified fraction and even then were less efficient. 相似文献
83.
The possible central integrative mechanisms, responsible for the earlier reported, differentiated reflex engagement of the renal and muscle vessels and the heart from cardiac ventricular receptors and arterial baroreceptors, respectively, were analyzed in atropinized cats. The reflex renal vessel, muscle vessel and heart rate responses, expressed as per cent of maximum, to graded activations of arterial baroreceptors (sinus pressure variations) and stimulations of ventricular receptor afferents in the cardiac nerve were systematically compared. Cardiac nerve stimulation with low frequencies was found to elicit more pronounced reflex renal vessel responses than muscle vessel and heart rate responses. In contrast, elevations of sinus pressure induced equally pronounced renal and muscle vessel responses. High frequency cardiac nerve stimulation elicited maximal reflex renal vessel responses, but only submaximal effects on muscle vessels and heart rate, while intense baroreceptor stimulation induced maximal reflex effector responses throughout. The submaximal heart rate response to cardiac nerve stimulation is probably due to a simultaneous activation of excitatory afferents. On the other hand, the less pronounced muscle than renal vessel responses when the cardiac nerve was stimulated probably reflect a relatively sparse innervation of muscle vasomotor neurons by ventricular receptor afferents, which seem instead to be preferentially oriented towards renal vasomotor and, possibly, cardiac motor neurons. 相似文献
84.
85.
Gunnar D. Bloom Bengt Carls ke Danielsson Sten Hellstrm Roger Henriksson 《Anatomical record (Hoboken, N.J. : 2007)》1981,201(4):645-654
Rats were sympathetically denervated on one side by avulsion of the superior cervical ganglion either immediately after birth (within 4 hr) or when the salivary glands were fully developed. Nine weeks after ganglionectomy the parotid glands were subjected to microscopical studies. As shown by the lack of specific fluorescence, sympathetic denervation caused an almost total depletion of catecholamines in the acini. This was further substantiated at the electron microscopic level using KMnO4 as fixative. No alterations in either gland weight or in acinar cell size were noticeable after adult sympathectomy. On the other hand, neonatal denervation caused a decrease in gland weight as well as acinar cell hypotrophy. The mean volume of individual acinar cells was reduced by roughly 25% and the granule volume density by about 50%. Also the mean volume of individual granules was decreased. These findings indicate an important role for the sympathetic nerve system in the maturation of the rat parotid gland. 相似文献
86.
87.
M. S. Reid M. Herrera-Marschitz T. Hökfelt N. Lindefors H. Persson U. Ungerstedt 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1990,82(2):293-303
Summary The striatonigral pathway contains several neurotransmitters which may regulate the activity of the nigrostriatal dopamine projection in the rat. This was investigated by measuring extracellular dopamine levels in the striatum, using microdialysis, after injections of GABA (300 nmol/0.2 l), dynorphin A (0.5 nmol/0.2 l), substance P (0.07 mnol/0.2 l) or neurokinin A (0.09 nmol/0.2 l) into the ipsilateral substantia nigra, pars reticulata (SNR). Intranigral injections of GABA or dynorphin A inhibited, while intranigral injections of substance P or neurokinin A stimulated dopamine levels in the ipsilateral striatum. In rats with ibotenic acid lesions (2.5 g/0.5 l) in the SNR, intranigral injections of GABA or dynorphin A inhibited, while intranigral injections of substance P or neurokinin A stimulated dopamine levels in the ipsilateral striatum. These responses were not significantly different than those in unlesioned rats. Analysis of the intranigral lesion with in situ hybridization revealed a heavy loss of glutamic acid decarboxylase mRNA expression in the SNR and a significant loss of tyrosine hydroxylase (TH) mRNA expression in the SNC. Immunohistochemical analysis revealed a disappearance of TH-Like immunoreactivity (LI) im dendrites in the SNR, a considerable loss of TH-LI cell bodies in the SNC and a restricted loss of neuropeptide K-LI in the SNR around the tip of the injection cannula. Furthermore, lesioned rats rotated ipsilateral to the lesion after apomorphine (1 mg/kg, s.c.), indicating that the basal ganglia output mediated via the SNR GABA neurons was impaired on the lesioned side. Analysis of the striatum revealed that a dense TH-LI fiber network could still be seen on the lesioned side. Furthermore, basal and amphetamine stimulated extracellular dopamine levels in the striatum on the lesioned side were not significantly depleted. This indicates that the ascending nigrostriatal dopamine projection was functionally intact on the lesioned side. These findings indicate that intranigral GABA, dynorphin A, substance P and neurokinin A modulation of ipsilateral striatal dopamine release is mediated via direct action on the nigrostriatal projection. Thus, it is suggested that the striatonigral pathway, which contains GABA, dynorphin, substance P and neurokinin A, exerts a direct regulatory effect on the activity of the nigrostriatal dopamine projection. 相似文献
88.
Olle Ringdén Marie Schaffer Katarina Le Blanc Ulla Persson Dan Hauzenberger Mohammad R Abedi Olle Olerup Per Ljungman Mats Remberger 《Biology of blood and marrow transplantation》2004,10(2):128-134
The aim of this study was to identify significant prognostic factors by using unrelated genomically HLA-A, -B and -DRB1-identical donors. Such data could help to choose the best donor. We studied 136 consecutive patients with hematologic malignancies and a median age of 32 years (range, 0-55 years) who received hematopoietic stem cell transplantation. Bone marrow grafts were given to 83 and peripheral blood stem cells to 53 patients. The cumulative incidence of grade II to IV acute graft-versus-host disease (GVHD) was 30% and of chronic GVHD was 54%. At 5 years, the overall transplant-related mortality (TRM) was 34%, and patient survival was 50%. In Cox multivariate analysis, 32 potential risk factors were analyzed. Monoclonal antibody OKT-3 during conditioning was correlated with grade II to IV acute GVHD, chronic GVHD, and TRM. HLA-DP mismatch was associated with poor TRM and poor survival. Cytomegalovirus-seropositive patients with a seronegative donor had a decreased leukemia-free survival. Five-year TRM was 14% with no risk factor, 38% with 1 risk factor, and 87% with 2 risk factors. The 5-year survival was 72%, 48%, and 30% with 0, 1, and 2 risk factors, respectively. We concluded that unrelated hematopoietic stem cell transplantation may be improved if an optimal donor and immunosuppression are chosen. 相似文献
89.
Prediction of AVM obliteration after stereotactic radiotherapy using radiobiological modelling 总被引:1,自引:0,他引:1
Mavroidis P Theodorou K Lefkopoulos D Nataf F Schlienger M Karlsson B Lax I Kappas C Lind BK Brahme A 《Physics in medicine and biology》2002,47(14):2471-2494
This study was carried out in order to derive the radiobiological parameters of the dose-response relation for the obliteration of arteriovenous malformation (AVM) following single fraction stereotactic radiotherapy. Furthermore, the accuracy by which the linear Poisson model predicts the probability of obliteration and how the haemorrhage history, location and volume of the AVM influence its radiosensitivity are investigated. The study patient material consists of 85 patients who received radiation for AVM therapy. Radiation-induced AVM obliterations were assessed on the basis of post-irradiation angiographies and other radiological findings. For each patient the dose delivered to the clinical target volume and the clinical treatment outcome were available. These data were used in a maximum likelihood analysis to calculate the best estimates of the parameters of the linear Poisson model. The uncertainties of these parameters were also calculated and their individual influence on the dose-response curve was studied. AVM radiosensitivity was assumed to be the same for all the patients. The radiobiological model used was proved suitable for predicting the treatment outcome pattern of the studied patient material. The radiobiological parameters of the model were calculated for different AVM locations, bleeding histories and AVM sizes. The range of parameter variability had considerable effect on the dose-response curve of AVM. The correlation between the dosimetric data and their corresponding clinical effect could be accurately modelled using the linear Poisson model. The derived response parameters can be introduced into the clinical routine with the calculated accuracy assuming the same methodology in target definition and delineation. The known volume dependence of AVM radiosensitivity was confirmed. Moreover, a trend relating AVM location with its radiosensitivity was observed. 相似文献
90.
Mikko?PS?AresEmail author Maria?Stollenwerk Anneli?Olsson Bengt?Kallin Stefan?Jovinge Jan?Nilsson 《BMC immunology》2002,3(1):13