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排序方式: 共有590条查询结果,搜索用时 15 毫秒
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Per Hartvig S.Å. Eckernäs Leif Lindström Bengt Ekblom Ulf Bondesson Hans Lundqvist Christer Halldin Kjell Någren Bengt Långström 《Psychopharmacology》1986,89(2):248-252
By means of positron emission tomography the uptake and kinetics of N-(methyl-11C)clozapine in different brain regions have been studied in Rhesus monkeys. 11C-clozapine rapidly entered the brain and maximum radioactive uptake was seen 5–12 min after administration. Highest uptake was measured in the striatum. Other regions with an uptake higher than in the cerebellum were thalamus and mesencephalon. The radioactivity from different brain regions decreased with an elimination half-life of about 5 h and parallelled the plasma kinetics of unlabelled clozapine. The striatum/cerebellum ratio of 11C-clozapine-derived radioactivity remained constant during the period studied and did not change after pretreatment with atropine. In contrast, the striatum/cerebellum ratio was somewhat lower after pretreatment with N-methylspiperone (NMSP), indicating competition for the same binding sites in the striatum. After pretreatment with increasing doses of clozapine, a dose-dependent protection of binding sites in the striatum for 11C-NMSP was seen. It is concluded that clozapine is more loosely bound to dopamine receptors in the striatum than N-methylspiperone and that the kinetics of clozapine in the brain parallel that in the plasma. The binding properties of clozapine within the brain may explain some of the clinical properties of the drug. 相似文献
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Seventeen consecutive selected patients rehabilitated by means of a full maxillary bridge on osseointegrated implants ad modem Brånemark were evaluated over a 3-yr period. Besides a subjective evaluation by means of a questionnaire an examination of the occlusal relationship, chewing force, chewing efficiency and interocclusal threshold level was performed before, immediately after, 3–6 months after, and finally 3 yr after bridge installation. All subjects were very pleased with the oral rehabilitation. The chewing force and the chewing efficiency development increased over time, while the threshold level for interocclusal detection remained unchanged. The clinical dysfunction index according to Helkimo indicated that there was no marked change in signs of dysfunction of the patients' masticatory systems during the observation period. From the present longitudinal investigation one can conclude that the replacement of a full maxillary denture with a fixed prosthesis on osseointegrated implants, facing a natural dentition or an osseointegrated implant supported bridge in the opposite jaw, leads to a progressive increase of chewing efficiency and chewing force, and a constant subjective improvement of jaw function, while no masticatory dysfunction seems to occur during the observation period. 相似文献
5.
G. Akerstrm L. Grimelius H. Johansson H. Pertoft H. Lundqvist 《The American journal of pathology》1980,99(3):685-694
The density of parathyroid glands was estimated by a density gradient technique. Glandular density was found to be closely related to the parenchymal cell content as estimated with an image-analyzing computer in serial sections. The density gradient technique can therefore be used to determine the relative parenchymal content of parathyroid glands. The density gradient measurements are rapid and reproducible and constitute a suitable method for determining the parathyroid parenchymal cell mass. The convenience of the technique suggests that it should be very useful for intraoperative diagnosis. 相似文献
6.
Agneta Johansson Eva Särndahl Tommy Andersson Torbjörn Bengtsson Helen Lundqvist Claes Dahlgren 《Inflammation》1995,19(2):179-191
When the chemotactic peptide formylmethionyl-leucyl-phenylalanine binds to its cell surface receptor, a transmembrane signal is generated that activates the superoxide-producing NADPH oxidase of human phagocytes. Comparing monocytes and neutrophils with regard to the production of superoxide anion induced by the peptide, we found a similar time-course for both types of cells. In neutrophils, ligand binding induced a conversion of the receptor to a high-affinity form, a change suggested to be due to an association of the receptor-ligand complex to the Triton X-100-insoluble cytoskeleton. This event has been hypothesized to terminate the signal that activates the NADPH oxidase and thereby results in cessation of the cellular production of superoxide anion. Neutrophils preincubated with the cytoskeleton-disrupting drug cytochalasin B showed an increased and prolonged superoxide anion production after activation with the peptide, thus indicating that the cytoskeleton is involved in terminating this response. Formylmethionyl-leucyl-phenylalanine was also found to induce polymerization of actin in monocytes; however, cytochalasin B had no effect on the peptide-induced generation of superoxide anion in these cells. Furthermore, also in monocytes, ligand binding induced a conversion of the receptor to a high-affinity form; however, the receptor-ligand complex did not coisolate with the Triton X-100-insoluble cytoskeleton. These results indicate that, in monocytes, the NADPH oxidase activating pathway is terminated without any association of the receptor-ligand complex to the Triton X-100-insoluble cytoskeleton. 相似文献
7.
Agneta Nordberg Anders Lilja Hans Lundqvist Per Hartvig Kaarina Amberla Matti Viitanen Ulrika Warpman Monika Johansson Ewa Hellstrm-Lindahl Peter Bjurling Karl-Johan Fasth Bengt Lngstrm Bengt Winblad 《Neurobiology of aging》1992,13(6):747-758
Three patients with Alzheimer's disease, a 68-year-old woman with mild dementia and 2 men (aged 64 and 72 years) with moderate dementia were treated orally with the cholinesterase inhibitor tacrine (tetrahydroaminoacridine), 80 mg daily, for several months. The patients were investigated using positron emission tomography (PET) prior to, and after 3 weeks and 3 months of treatment. The PET studies involved a multi-tracer system consisting of [18F]-fluoro-deoxy-glucose (18F-FDG) (tracer for glucose metabolism); 11C-butanol (cerebral blood flow) and (S)(−)- and (R)(+)-[N-11C-methyl]-nicotine (nicotinic receptors; cholinergic neural activity). Tacrine treatment increased the uptake of 11C-nicotine to the brain. Significant reduced difference in uptake between the two enantiomers (S)(−)- and (R)(+)11C-nicotine was observed in the frontal and temporal cortices after tacrine treatment in all three patients. The kinetic analysis indicated increased binding of (S)(−)11C-nicotine in brain compatible with a restoration of nicotinic cholinergic receptors. The most pronounced effect was observed after 3 weeks and 3 months treatment in the patient with mild dementia. An increase in cerebral glucose utilization was found in the 68-year-old patient with mild dementia but also slightly in the 64-year-old man with moderate dementia when treated with tacrine for 3 months. Tacrine administration did not affect cerebral blood flow. The PET data obtained after 3 weeks of tacrine treatment was paralleled by improvement in neuropsychological performance. This study shows in vivo by PET neurochemical effects induced in brain by treatment with tacrine to Alzheimer patients. Intervention with tacrine in the early course of the disease might be necessary for clinical improvement. 相似文献
8.
M el-Salhy E Wilander M Lundqvist G Nilsson A J Moody K Imagawa L Grimelius 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1988,96(6):537-542
The occurrence of glucagon/glucagon-like immunoreactivity in 31 small intestinal, 34 rectal and 18 appendiceal carcinoids were investigated immunocytochemically using, sequence specific antisera. Glucagon/GLI immunoreactive cells were found in five small-intestinal and five rectal carcinoids, but none were observed in any of the appendiceal carcinoids examined. Glucagon/GLI immunoreactive cells constituted a minor cell population, except in one rectal carcinoid, where most of the tumour cells were of this type. Glucagon/GLI immunoreactive cells were detected with only some sequence-specific antisera, and not with antisera directed against the rest of the glucagon/glicentin molecule. This might indicate that these cells contain a molecule which shares some antigenic binding sites with glucagon/glicentin rather than genuine glucagon/glicentin. It is concluded that this finding contributes to explain why hindgut carcinoids rarely give rise to symptoms related to neuro-endocrine product(s). 相似文献
9.
Anders Lundqvist Adiba Isa Thomas Tolfvenstam G?ran Kvist Kristina Broliden 《Journal of clinical virology》2005,33(1):71-74
BACKGROUND: Human parvovirus B19 (B19) polymerase chain reaction (PCR) is now a routine analysis and serves as a diagnostic marker as well as a complement or alternative to B19 serology. The clinical significance of a positive B19 DNA finding is however dependent on the type of tissue or body fluid analysed and of the immune status of the patient. OBJECTIVES: To analyse the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients. STUDY DESIGN: Parvovirus B19 DNA was analysed in paired bone marrow and serum samples by nested PCR technique. Serum was also analysed for B19-specific IgG and IgM antibodies and the results were compared with clinical and epidemiological data. RESULTS AND CONCLUSIONS: B19 IgG was found in 41 of 50 patients (82%) whereas none was B19 IgM positive. The serologic evaluation showed that none of the patients had acute B19 infection. However, B19 DNA was detected by PCR in 13 of 50 (26%) bone marrow samples from these patients indicating a high frequency of persistent infection compared with previous reports of patient groups and healthy controls. In the study, 22 patients had rheumatoid arthritis (RA) and 7 of these RA patients were B19 DNA positive in bone marrow. Rheumatoid factor was positive in 4 of the 7 B19 DNA positive RA patients as compared with Rheumatoid factor positivity in all of the 15 B19 DNA negative RA patients. Erosive arthritis in X-ray was less common in the B19 DNA positive group than in the B19 DNA negative group. A high frequency of parvovirus B19 DNA was thus detected in bone marrow samples in rheumatic patients. The clinical data does not support a direct association between B19 PCR positivity and rheumatic disease manifestation. Therefore, the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients must be interpreted with caution. 相似文献
10.
All sturgeon VL segments isolated in this study belong to a single family, VLI, which can be divided into two subfamilies. Of the 79 cDNA clones isolated, 76 belong to the larger subfamily, VLIa, and only 3 clones constitute the smaller subfamily, VLIb. To evaluate variability, the Shannon entropy was estimated for each individual amino acid position, and to facilitate comparisons of variability between species the mean entropy of the CDR regions was calculated. In such a comparison, the sturgeon was found to have CDR1 and CDR3 variability approaching those found in mouse and clawed frog, but showed very low variability for CDR2. Amino acid position 50 does however display variability in the range of mouse and clawed frog. It is further confirmed that the sturgeon has numerous J segments, but that the junctional diversity does not contribute greatly to the diversity of the light chain. Comparisons of cDNA clones and a genomic VL segment indicate that the VL undergoes changes, particularly in the CDR regions, in a manner that can be explained by somatic hypermutation and/or gene conversion. 相似文献