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21.
Nine children, aged 5 to 11 years, with subacute or chronic meningitis were studied. Symptoms started during the summer season in all patients and in eight of the patients the disease began with a localized erythematous lesion (ECM), mostly in the face. In one patient only there was a history of an insect bite at the site of the erythema. The neurological abnormalities included aseptic meningitis, peripheral facial nerve palsy (5/9) and oculomotor nerve palsy (1/9). Most children complained of headache, fatigue, loss of appetite and had a low grade fever. High antibody titers to Borrelia spirochetes in serum and/or cerebrospinal fluid (CSF) were demonstrated by ELISA in eight of the nine patients and by indirect immunofluorescence assay (IFA) in three patients. All patients had a dramatic improvement in their general condition and became afebrile within three days of institution of i.v. penicillin G treatment (i.v. cefuroxime in one patient).  相似文献   
22.
Validity of repeated dietary measurements in a dietary intervention study.   总被引:1,自引:0,他引:1  
The aim of the study was to evaluate the compliance in a dietary intervention study. When drawing conclusions about the relationship between dietary intake and disease occurrence/disease-related variables it is important to obtain valid dietary data. 20 healthy, non-smoking normal-weight omnivores changed from a mixed to a lactovegetarian diet. Dietary surveys (four 24 h recalls per person and time-period), urinary and faecal sample collections were performed before and 3, 6 and 12 months after the dietary shift. The validation of energy, protein, sodium and potassium yielded approximately the same ratio of dietary intake to biological marker at 0 and 3 months. This ratio decreased towards 6 months and continued to decrease towards 12 months. The fibre intake was compared to the total faecal weight directly and indirectly by calculating the fibre intake from the stool weight, the water content in faeces and the excretion of short-chain fatty acids (SCFAs). These four methods of fibre validation showed that the ratio of dietary intake to biological marker was always highest at 12 months, indicating an overestimation of the fibre intake at the end of the study. This is the first time these methods of validating fibre intake have been used in an epidemiological study. The ratio of dietary calcium intake to urinary and faecal calcium excretion did not show any statistical difference between the period before and 3 months after the dietary shift. To conclude, almost all investigated dietary data show approximately the same validity before and 3 months after the dietary shift, and show the least validity 12 months after the dietary shift. Thus, this study demonstrates that it is difficult to obtain valid dietary data 1 year after a drastic dietary change, indicating a decreased compliance to the new dietary regimen at the end of the 1 year study period. This represents important information when attempting to relate biological effects to dietary intake, and illustrates the importance of using biological markers for food intake in dietary surveys.  相似文献   
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Rutaecarpine alkaloids have the capacity to inhibit specific2,3,7,8-[1,6-3H]tetrachlorodibenzo-p-dioxin (TCDD) binding inrat liver cytosol, as analysed by electrofocusing in polyacrylamidegel. The IC50 value for binding of 7,8-dehydrorutaecarpine wasestimated to 7 nM indicating a high-affinity interaction, whereasrutaecarpine appeared less active (IC50 110 nM). These findingsare of interest in view of the fact that analogues to thesecompounds may be formed following UV-irradiation of tryptophanand that such photo-products have been suggested to constitute(the) endogenous ligand(s) for the TCDD receptor. As furthersupport of this notion, the rutaecarpine alkaloids investigatedcould be fitted into a rectangle of 6.8x13.7 A, a characteristiccommon for most high affinity ligands of the TCDD receptor hithertostudied. In view of their structural similarity to dehydrorutaecarpineand the agreement of their mol. wt with that of the photoproductwith the highest affinity for the TCDD receptor, we suggestdeaza-analogues of dehydrorutaecarpine to represent possiblecandidates for the endogenous TCDD receptor ligand.  相似文献   
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Trichoplusia ni immune genes up-regulated in response to bacterial infection have been isolated using differential display polymerase chain reaction. Here we report the cloning and characterisation of a gut-specific immune gene encoding an azurocidin-like protein. The deduced protein is 317 amino acid residues long with a hydrophobic C-terminus and a predicted 17-residue signal peptide. The mature T. ni protein shows 30% identity to human azurocidin, an antibacterial protein. Like azurocidin, the T. ni protein contains two amino acid substitutions in the active site triad normally present in serine proteases. The T. ni protein was synthesised with a six-histidine C-terminal extension using the baculovirus expression system. Sequencing of the recombinant azurocidin-like protein confirmed the predicted cleavage of the signal peptide. Northern blots show that T. ni azurocidin-like protein is expressed solely in the larval gut and that expression is up-regulated by injecting or feeding bacteria. Expression reaches its highest level at 10 h after bacteria injection.  相似文献   
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28.
Transmitter characteristics of small mesenteric arteries from the rat   总被引:7,自引:0,他引:7  
We have studied the neurogenic response of small mesenteric arteries from the rat to evaluate the involvement of possible co-transmitters under various modes of stimulation. Segments of small branches of the mesenteric artery were mounted in a myograph and the intramural nerves were activated with transmural electrical stimulation. A single stimulation of the nerves caused a contraction that was reduced by only 20% in the presence of adrenergic blocking agents (prazosin or phenoxybenzamine), whereas the steady-state response to continuous nerve stimulation of high frequency was reduced by 90-95%. In contrast, all responses to applied noradrenaline in doses up to at least 1 mM were eliminated by phenoxybenzamine treatment. The stable ATP analogue, alpha,beta-methylene ATP, reduced the response to a single nerve stimulation by 70%, but reduced the contraction caused by continuous high-frequency nerve stimulation by only 10%. None of these agents affected the response to applied neuropeptide Y (NPY). The response of relaxed vessels to nerve stimulation was totally blocked by the combination of an adrenoceptor-blocking agent and alpha,beta-methylene ATP, although even in this situation a further neurogenic response could be revealed in vessels precontracted with vasopressin. Responses to either single stimuli or brief burst stimulations were potentiated after high-frequency stimulation. Both the adrenergic and non-adrenergic components were enhanced to roughly the same extent. Also the potentiated response was eliminated by the combined application of prazosin and alpha,beta-methylene ATP. The non-adrenergic transmitter in the sympathetic nerves of small arteries thus appears to be the dominant transmitter during low-frequency nerve stimulation, causing rapid but phasic activation. Noradrenaline is the most important transmitter for higher frequencies, exerting slower but sustained contractions. The post-stimulatory potentiation affects both the adrenergic and the non-adrenergic part of the neurogenic response.  相似文献   
29.
Cryostat sections of colon from germ-free rats were incubated with sera from patients with ulcerative colitis or healthy controls. With peroxidase-conjugated antibody from sheep to human immunoglobulin, a distinct staining of goblet cell surface was observed with the patients' sera but not with the controls. The staining compares well with that obtained by indirect immunofluorescence. It could easily be distinguished from staining due to endogenous peroxidase.  相似文献   
30.
Real-time PCR was evaluated as a quantitative diagnostic method for Chlamydia pneumoniae infection using different respiratory samples. Real-time PCR had efficiency equal to or better than that of nested touchdown PCR. This study confirmed sputum as the best sampling material to detect an ongoing C. pneumoniae infection.  相似文献   
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