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991.
Blood coagulation and fibrinolysis after long-duration treadmill exercise controlled by individual anaerobic threshold 总被引:2,自引:0,他引:2
Hilberg T Gläser D Reckhart C Prasa D Stürzebecher J Gabriel HH 《European journal of applied physiology》2003,90(5-6):639-642
For rehabilitation training it is recommended that the intensity of exercise should be clearly below the individual anaerobic threshold (IAT). We investigated blood coagulation, particularly endogenous thrombin potential (ETP) and fibrinolysis following a standardized treadmill (TR) ergometer test at 90% IAT for 60–120 min. Sixteen healthy male non-smokers underwent the TR test. Blood samples were taken after a 30-min rest, immediately after exercise, and 2 h after exercise completion. Extrinsic and intrinsic total (TTPex+in) and endogenous (ETPex+in) thrombin potential, prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complex (TAT), plasmin-2-antiplasmin complex (PAP), D-dimer, tissue plasminogen activator antigen and activity (tPA-AG and tPA-ACT) and plasminogen activator inhibitor type 1 antigen and activity (PAI-1-AG and PAI-1-ACT) were measured. Immediately after TR, F1+2, TAT and TTPex+in were increased (P<0.05) while ETPex+in remained unchanged. In contrast, PAP, D-dimer, tPA-AG, tPA-ACT (P<0.05) were distinctly enhanced while PAI-1-ACT was decreased (P<0.05) immediately after exercise. The changes in tPA-AG, tPA-ACT, and PAI-1-ACT were reversed to nearly baseline while the enhancement in PAP and D-dimer was prolonged by more than 2 h after exercise. Long-duration exercise between 60 and 120 min controlled by IAT (90%) on a TR ergometer only implicates a small increase in thrombin generation markers and total (free and 2-macroglubulin-bound thrombin), but not in endogenous (free) thrombin potential alone. In contrast, fibrinolysis is distinctly increased after this type of exercise. Endurance exercise with an intensity below 90% IAT and a duration below 2 h generates a more favourable condition for fibrinolysis than for blood coagulation in healthy young subjects. Data are given as mean (SD). 相似文献
992.
993.
In 1896 Kuttner reported four cases which he described as induration of the submandibular gland. Histologically, they showed chronic inflammation and fibrosis. Sporadic cases of this entity that have come to be known as Kuttner's tumor or chronic sclerosing sialadenitis of the submandibular gland and have been reported throughout the 20th century. This inflammatory tumor has been under-recognized, and awareness of its importance and probable immunologic background have recently become evident. We report an unusual case of chronic sclerosing sialadenitis, affecting both parotid glands, both submandibular glands, and minor salivary glands of the oral cavity, and explore the immunohistochemical profile of this entity. 相似文献
994.
Inactivation of Exonuclease 1 in mice results in DNA mismatch repair defects,increased cancer susceptibility,and male and female sterility 总被引:12,自引:0,他引:12 下载免费PDF全文
Wei K Clark AB Wong E Kane MF Mazur DJ Parris T Kolas NK Russell R Hou H Kneitz B Yang G Kunkel TA Kolodner RD Cohen PE Edelmann W 《Genes & development》2003,17(5):603-614
Exonuclease 1 (Exo1) is a 5'-3' exonuclease that interacts with MutS and MutL homologs and has been implicated in the excision step of DNA mismatch repair. To investigate the role of Exo1 in mammalian mismatch repair and assess its importance for tumorigenesis and meiosis, we generated an Exo1 mutant mouse line. Analysis of Exo1(-/-) cells for mismatch repair activity in vitro showed that Exo1 is required for the repair of base:base and single-base insertion/deletion mismatches in both 5' and 3' nick-directed repair. The repair defect in Exo1(-/-) cells also caused elevated microsatellite instability at a mononucleotide repeat marker and a significant increase in mutation rate at the Hprt locus. Exo1(-/-) animals displayed reduced survival and increased susceptibility to the development of lymphomas. In addition, Exo1(-/-) male and female mice were sterile because of a meiotic defect. Meiosis in Exo1(-/-) animals proceeded through prophase I; however, the chromosomes exhibited dynamic loss of chiasmata during metaphase I, resulting in meiotic failure and apoptosis. Our results show that mammalian Exo1 functions in mutation avoidance and is essential for male and female meiosis. 相似文献
995.
The exact role and timing of reactivation of telomerase, a key enzyme implicated in cellular immortalization and transformation in the multistep process of laryngeal carcinogenesis, is still unknown. We attempted to (1) determine that quantitative differences exist in the levels of telomerase catalytic subunit (hTERT) mRNA expression among different grades of laryngeal epithelial abnormalities classified according to the Ljubljana classification; (2) determine that telomerase reactivation is an important, most probably early event in laryngeal carcinogenesis; and (3) analyze whether the relative quantity of hTERT mRNA can be used as a molecular biomarker in the early detection of precancerous lesions. The relative quantity of hTERT mRNA, expressed as an hTERT index, was analyzed in 140 frozen laryngeal tissue specimens representing different morphological stages of laryngeal carcinogenesis by using a commercially available LightCycler Telo TAGGG hTERT Quantification kit. The presence and relative quantity of hTERT mRNA in laryngeal epithelium increases progressively with the degree of epithelial abnormalities. hTERT mRNA was detectable in 1/15 normal laryngeal epithelia (7%, mean hTERT index 0.02), 3/15 simple hyperplasias (20%, mean hTERT index 0.09), 10/27 abnormal hyperplasias (37%, mean hTERT index 0.18), 9/12 atypical hyperplasias (75%, mean hTERT index 0.74), 8/9 intraepithelial carcinomas (89%, mean hTERT index 1.82), and 53/62 invasive laryngeal squamous cell carcinomas (85%, mean hTERT index 2.51). Statistical analysis revealed two groups of laryngeal epithelial changes with significant differences in the levels of hTERT mRNA expression (P <.0033): (1) normal and reactive hyperplastic laryngeal epithelium (simple and abnormal hyperplasia) and (2) atypical hyperplasia (precancerous lesion), intraepithelial and invasive laryngeal squamous cell carcinoma. The results of the present study suggest that telomerase reactivation is an early event in laryngeal carcinogenesis, detectable already at the stage of precancerous laryngeal epithelial changes. Nevertheless, other genetic abnormalities appear to be necessary for progression of these epithelial abnormalities toward invasive laryngeal squamous cell carcinoma. 相似文献
996.
Schlitt T Palin K Rung J Dietmann S Lappe M Ukkonen E Brazma A 《Genome research》2003,13(12):2568-2576
997.
Mesenteric lymph nodes are critical for the induction of high-dose oral tolerance in the absence of Peyer's patches 总被引:7,自引:0,他引:7
Spahn TW Weiner HL Rennert PD Lügering N Fontana A Domschke W Kucharzik T 《European journal of immunology》2002,32(4):1109-1113
We have previously demonstrated the loss of oral tolerance (OT) in lymphotoxinalpha-/- (LTalpha-/-) and TNFalpha / lymphotoxinalpha deficient (TNFalpha / LTalpha-/-) mice which have defective Peyer's patches (PP) and lymph node (LN) development. We have now studied OT in BALB / c mice with differential defects of the gut-associated lymphoid tissue (GALT) caused by inhibition of LTbetaR signaling during fetal development. Treatment of pregnant mice with LTbetaR-IgG (LTbetaRIgG) and TNFR I55-IgG (TNFR55IgG) abrogates the formation of PP (LTbetaRIgG) or of PP and mesenteric LN (MLN) (LTbetaRIgG / TNFRIgG) without genetically deleting the respective cytokine pathways. OT was readily induced in mice without PP but retaining MLN (PP null / LN +). In contrast, OTcould not be induced in mice lacking both MLN and PP (PP null / MLN null) as shown by the inability of these mice to suppress IFN-gamma secretion or DTH reactions. We next assessed OT in 129 x B6 LTalpha-/- mice with and without MLN. Timed treatment of pregnant LTalpha-/- mice with an agonist anti-LTbetaR mAb induces formation of MLN but not of PP in LTalpha-/- mice. LN + LTalpha-/- mice developed OT while LN LTalpha-/- mice were resistant to OT induction. Taken collectively, the data show that in the presence of MLN PP are not required for OT induction and that the presence of MLN is sufficient for OT induction in the LTalpha-/- model. 相似文献
998.
The effect of direct intrahypothalamic nitric oxide (NO) administration on the release of selected amino acids in the hypothalamic supraoptic nucleus (SON) with and without concomitant forced swimming was investigated. Adult male Wistar rats were chronically fitted with U-shaped microdialysis probes in the SON and forced to swim for 10-min in 20-degree C warm water. Thirty-min microdialysis samples were collected before, during and after the forced swimming period while NO was administered into the SON via microdialysis. The results show that NO administration in combination with forced swimming affects the release of aspartate, glutamate, taurine, and gamma aminobutyric acid (GABA) in different patterns. Whereas the release of the excitatory amino acids aspartate and glutamate was triggered only during NO administration and forced swimming, the inhibitory amino acids GABA and taurine were found in the extracellular fluid in increased concentrations also after the treatment. These data indicate that NO administration differently affects the release of excitatory and inhibitory amino acids within the SON. Thus, SON neurons which contain high concentrations of neuronal NO synthase, might contribute to the regulation of their own secretory activity by releasing NO that controls the orchestrated release of excitatory and inhibitory amino acids from axon terminals of afferences and interneurons as well as release from glial cells. 相似文献
999.
Theodore Kushnick Thomas G. Irons John E. Wiley Elizabeth A. Gettig Kathleen W. Rao Susan Bowyer John M. Opitz James F. Reynolds 《American journal of medical genetics. Part A》1987,28(3):567-574
Two white females, age 2 1/2 and 33 years, respectively, were investigated because of severe mental retardation associated with neurologic abnormalities, coarse face, and soft tissue syndactyly involving upper and lower limbs. Each had cytogenetic findings of a mosaic variant of Ullrich-Turner syndrome with X ring chromosome in peripheral lymphocyte and skin fibroblasts. Early X replication occurred in one-third of the X ring chromosomes; there was no evidence for X-autosome translocation involving either X and an autosomal duplication; results of studies for fragility of the X chromosomes were unremarkable. In situ hybridization with an X centromere probe was positive for the ring. To our knowledge, the unusual constellation of cytogenetic, physical, and mental findings seen in these 2 individuals has not been reported previously. 相似文献
1000.
A microtiter plate ELISA with semipurified human nerve sonicate antigen(s) (NA) was used to screen the sera of leprosy patients. High titers of IgG and low titers of IgM classes of antineural antibodies directed to peripheral nerve antigens were detected in LL, BL, BB, BT, and TT categories of leprosy. In the Western blot, leprosy sera recognized 50- to 55-, 85- and 108-kDa molecular weight protein bands of NA. The identity of these protein bands immunoreactive with leprosy sera was checked with a panel of commercially available antibodies to known neural proteins. The 50- to 55-kDa band reacted with anti-S100 and anti-glial fibrillary acidic protein antibodies while 85 and 108 kDa could not be identified. Whole immunoglobulins isolated from leprosy sera with high titers of antineural antibodies induced cytotoxicity of the cultured glial cell line in the presence of complement. 相似文献