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991.
Structural and mechanical adaptations in response to sustained changes in arterial pressure were studied on abdominal aorta of the male rat. Two models were used: 1. Aortic ligature (L), immediately below the renal arteries producing hypotension distal to the knot (duration before sacrifice 6 weeks or 3 months). 2. One-clip renal hypertensive rats (H) (duration 6 weeks). Normotensive sham-operated rats (C) served as controls. At sacrifice mean tail artery pressure was L: 58 +/- 1, C: 110 +/- 3, and H: 163 +/- 5 mmHg (SE, N=6). Segments of abdominal aorta were mounted in vitro for determination of their length-tension relations (activation: High-K+ solution with 2.5 mM Ca2+). At end of experiments the vessels were supramaximally stimulated at optimal circumference (1o) for active force (activation: High-K+ solution with 10 mM Ca2+, and 10(-5) M noradrenaline), and then fixated for light and electron microscopy. Passive and active length-tension relations were shifted towards lower and higher circumference values for hypo- and hypertensive vessels, respectively. The 1o values were L: 3.60 +/- 0.13, C: 4.44 +/- 0.19, and H: 4.91 +/- 0.29 mm. The media thickness at 1o was reduced in L: 56.0 +/- 3.3, and increased in H: 81.3 +/- 2.4 compared to C: 73.4 +/- 1.8 micron. Maximal active wall stress was L: 46.6 +/- 9.8, C: 74.2 +/- 7.0, and H: 83.8 +/- 7.7 mN/mm2. Intracellular volume (ICV) in the media was L: 30 +/- 2, C: 45 +/- 3, and H: 44 +/- 1% (n=4 for each).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
Santer R Muhle H Suormala T Baumgartner ER Duran M Yang X Aoki Y Suzuki Y Stephani U 《Molecular genetics and metabolism》2003,79(3):160-166
We report the clinical course and biochemical findings of a 10-year-old, mentally retarded girl with late-onset holocarboxylase synthetase (HCS, gene symbol HLCS) deficiency and only partial response to biotin. On treatment, even with an unusually high dose of 200mg/day, activities of the biotin-dependent mitochondrial carboxylases in lymphocytes remained below 50% of the mean control values. Not only urinary 3-hydroxyisovaleric acid excretion has been persistently elevated, but also plasma and, with even higher concentrations, cerebrospinal fluid 3-hydroxyisovaleric acid have not normalized. The unusual and insufficient response of this patient to biotin treatment can be explained by the effect of the combination of the common HLCS allele IVS10 +5 g>a on one chromosome and a truncating mutation on the other. This case illustrates mechanisms involved in the genotype-phenotype correlation that unequivocally exists in HCS deficiency. 相似文献
993.
994.
A storage telemetrical method using thermoluminescent (TL) dosimeters for long-term measurements of incorporated radioactive substances in unrestrained rats has been developed. The system has been used in combination with radiotelemetrical registration of the circadian temperature rhythm. By sequential replacement of double TL dosimeters (60 mg, CaSO4:Dy) through an implanted silicon tube, the concentration of different radionuclides can be determined over long periods. The persistence of the circadian temperature rhythm indicates that the animals were unaffected by the experimental conditions. The relative uncertainty of the dosimeter system and the temperature transmitter is approximately +/- 2% (SD) at 5 mR exposures and +/- 0.05 degrees C, respectively. The weight of the system in total is 5.7 g. Disappearance studies (36-48 h) have been performed with the beta-emitters, 32P nad 42K, in subcutaneous tissues and tumor tissue. This TL method permits the repetition of an experiment on the same rat several times, and thereby avoids errors due to biological variations between animals. 相似文献
995.
The effect of Levamisole on peripheral blood lymphocyte subpopulations in patients with rheumatoid arthritis and ankylosing spondylitis. 总被引:1,自引:0,他引:1 下载免费PDF全文
Although Levamisole, an antihelmintic drug, has shown to have some modulatory effect on the immune response in clinical trials and experimental models, its mode of action remains obscure. In a group of fifteen patients with rheumatoid arthritis and ankylosing spondylitis receiving Levamisole on an intermittant regime, simultaneous determinations of the lymphocyte subpopulations were made prior to Levamisole administration and 3 months thereafter. No significant changes were observed either in the absolute or in the relative number of T- and B-cell populations, while a statistically significant reduction was found in the "null" cells. These findings suggest that the immune potentiating effect of Levamisole may at least partially be due to a maturation process of the "null" cells. 相似文献
996.
997.
Expression of putative virulence factors by clinical isolates of Klebsiella planticola 总被引:3,自引:0,他引:3
A total of 92 clinical isolates of Klebsiella planticola from man was examined with respect to the production of haemagglutinins and siderophores, serum resistance and distribution of capsular types. For comparison, a group of 207 clinical isolates of K. pneumoniae was also studied. The percentages of K. planticola strains able to express mannose-sensitive haemagglutination, indicating type 1 fimbriae (83%) and mannose-resistant and Klebsiella-like agglutination, indicating type 3 fimbriae (69%), as well as to produce the siderophores enterobactin (100%) and aerobactin (2.2%) were almost identical to those of the K. pneumoniae strains. Similarly, the proportion of serum-resistant strains (30%) was comparable to that of K. pneumoniae (25%). The capsule types most often detected in K. planticola were K14 (13%), K2 (9%) and K70 (9%). The incidence of K2, which is the predominant capsular type in K. pneumoniae, was similar in both species. These findings show that K. planticola, which is being detected with increasing frequency in clinical specimens from man, has the ability to express similar putative virulence factors to K. pneumoniae, suggesting that they may have similar pathogenicity. 相似文献
998.
C Marosi U K?ller E Koller-Weber I Schwarzinger B Schneider U J?ger P Vahls H Nowotny H Pirc-Danoewinata G Steger 《Cancer Genetics and Cytogenetics》1992,61(1):14-25
One hundred-twenty-five adult patients with de novo acute myeloid leukemia (AML) were treated according to a standard 7 + 3 induction regimen. Karyotype and immunological phenotype of blasts examined prior to treatment were correlated with each other, with response to treatment and duration of survival. The following monoclonal antibodies (mAbs) were used for immunological phenotyping: VIM-D5 (CD15), MY7 (CD13), MY9 (CD33), VIM-2 (CDw65), VIM-13 (CD14), 63D3 (CD14), VID-1 (anti HLA-DR), WT1 (CD7), CLB-Ery3 (antiblood group H antigen), C17-27 (CD61), and an antiserum against TdT. Despite a considerable overlap between the individual groups, patients with specific aberrations as defined by the MIC classification (n = 39) showed distinct, characteristic, myeloid or myelomonocytic immunophenotypes. In M2/t(8;21) there was a significant association with negativity to CD13, in M3/t(15;17) with negativity to CD15 and HLA-DR, whereas in M4/inv(16) expression of blood group H antigen was unexpectedly found. The response to therapy, as well as rate of complete remission as duration of survival, was better in patients with M2/t(8;21), M3/t(15;17), and M4Eo/inv(16) as compared to all other patients and significantly worse in patients with M5a/t/del(11)(q23). In 35 patients with normal karyotype and 16 patients with cytogenetic anomalies not presently associated with FAB subtypes the expected correlations of rather immature myeloid immunologic phenotypes with M1 and M2 morphology and CD14 expression in monoblastic leukemias was found. Remission rate and survival were significantly worse in 19 patients with complex nonrandom aberrations, where blast cell expression of blood group H antigen and of TdT were significantly increased. 相似文献
999.
This article reports on the experience with 38 biopsies from nasal mucosa, submitted with the question of immotile cilia syndrome. Fixation in glutaraldehyde with MgSO4 is preferable. At least 50 cilia should be scrutinized in the electron microscope, and dynein arms, radial spokes, sheaths, nexin links and orientation should be tabulated. Six cases displayed virtual absence of inner and outer dynein arms. The orientation of these cilia was random. Two of the patients had situs inversus. In biopsies considered not to represent the immotile cilia syndrome, about four inner and seven outer dynein arms were found per cilium. 相似文献
1000.
Niederwieser A. Joller P. Seger R. Blau N. Prader A. Bettex J. D. Lüthy R. Hirschel B. Schaedelin J. Vetter U. 《Journal of molecular medicine (Berlin, Germany)》1986,64(7):333-337
Summary An increase in total urinary neopterin was observed in 12 of 13 patients with acquired immunodeficiency syndrome (AIDS), seven of 13 patients with lymphadenopathy, one of six healthy homosexual males, seven of ten adult patients with staphylococcal pneumonia, 11 of 12 children with viral infections, four of seven children with bacterial infections, and 12 of 13 children with various immune defects. Extremely high values of total urinary neopterin and monapterin were observed in severely ill patients with AIDS and those with familial hemophagocytic lymphohistiocytosis. Neopterin excretion was normal in two AIDS patients with Kaposi's sarcoma, but without opportunistic infections at that time. On reexamination of one of these patients later on, elevated neopterin values were noted. Parallel increases in neopterin and monapterin were found, whereas biopterin was usually normal. The increase in total neopterin was mainly due to 7,8-dihydroneopterin and was accompanied by an increase in 3-hydroxysepiapterin. Increased neopterin in urine is assumed to reflect the increase in GTP pool and GTP cyclohydrolase I activity as observed in stimulated monocytes. Thus, neopterin, as a measure of the activation of the nonspecific cellular immune system, may be used diagnostically to detect allograft rejection after transplantations and to follow-up HTLV-III positive patients.
Neopterin bei AIDS, anderen Immundefekten, Bakteriellen und viralen InfektionenAbbreviations AIDS acquired immunodeficiency syndrome - ARC AIDS related complex - BH4 tetrahydrobiopterin - GTP guanosine triphosphate Supported by the Swiss National Science Foundation, project 3.266-0.82 and 3.601-0.84 相似文献