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排序方式: 共有8952条查询结果,搜索用时 15 毫秒
981.
Jean-Louis Dhondt Patrick Ardouin Jean-Marie Hayte Jean-Pierre Farriaux 《Clinica chimica acta; international journal of clinical chemistry》1981,116(2):143-152
Large variations of pteridine elimination occur in childhood, due to the ontogenic development of the metabolism of tetrahydrobiopterin. The main feature is the slow maturation of biopterin synthesis whereas neopterin synthesis is high at birth; thus a high neopterin to biopterin ratio (4.4 ± 2.1) occurs in the neonatal period, a ratio which then decreases to adult values (0.5 ± 0.2). Comparing pteridine elimination of PKU patients with that of controls of the same age, a high excretion of biopterin and, to a lesser extent, of neopterin is found. In normal subjects, following an oral phenylalanine load, biopterin levels in urine and serum also increase, whereas variations of neopterin concentration are small. In rats, phenylalanine also leads to an increase of serum biopterin whereas liver biopterin decreases. This suggests that the main explanation for the biopterin increase in serum and in urine by phenyl-alanine is a release of the intracellular biopterin by the aminoacid. 相似文献
982.
Jean-Paul Chapelle Adelin Albert Camille Heusghem Jean-Pierre Smeets Henri E. Kulbertus 《Clinica chimica acta; international journal of clinical chemistry》1980,106(1):29-38
The prognostic significance of serum enzyme measurements in acute myocardial infarction was studied in 146 patients hospitalized shortly after the attack. Creatine kinase (CK), CK-MB, aspartate aminotransferase (ASAT) and lactate dehydrogenase (LDH) were serially determined every four hours during the first three days following admission.Peak enzyme levels correlated well with the cumulated CK release (r = 0.95, 0.74, 0.70 for CK, ASAT and LDH respectively). Among all enzyme measurements, LDH levels determined when CK reached its peak value provided the best discrimination between acute phase survivors (15 days) and non-survivors. LDH was also the best measurement for identifying patients with ventricular impairment. LDH and ASAT peak levels were more powerful predictors of the patient's risk than CK peak levels. CK levels determined later in the course of myocardial infarction were more discriminant, indicating prolonged CK elevation in non-survivors. There was no significant difference in CK-MB levels, nor in cumulated CK-MB amounts for survivors and non-survivors.It is concluded that serum LDH activity is a better predictor of the short term evolution of myocardial infarction than CK levels or infarct size estimations from serial CK determinations. 相似文献
983.
Bonnet S Béchade D Palazzo L Desramé J Baton O Bounaim A Baranger B Algayres JP 《Gastroentérologie clinique et biologique》2005,29(5):607-609
The diagnosis of hepatic cystadenoma is difficult with the conventional radiologic imaging. When these hepatobiliary cystic tumors are located in the left liver, Echoendoscopic ultrasound/Fine needle aspiration can help in the diagnosis by showing high levels of cystic CEA and CA 19-9 in a mucinous fluid. Definitive histological evaluation is assessed by the examination of the operative specimen. 相似文献
984.
Involvement of BAFF and APRIL in the resistance to apoptosis of B-CLL through an autocrine pathway 总被引:26,自引:11,他引:26 下载免费PDF全文
Kern C Cornuel JF Billard C Tang R Rouillard D Stenou V Defrance T Ajchenbaum-Cymbalista F Simonin PY Feldblum S Kolb JP 《Blood》2004,103(2):679-688
Tumor necrosis factor (TNF) superfamily members BAFF, or B-cell activation factor of the TNF family, and APRIL, a proliferation-inducing ligand, are involved in normal B-cell survival and differentiation. They interact with 3 receptors: BAFF-R, specific to BAFF; and TACI and BCMA, which are shared by BAFF and APRIL. We tested the potential role of these proteins in B-cell chronic lymphocytic leukemia (B-CLL) resistance to apoptosis. TACI and BAFF-R mRNAs were found in leukemic B cells. BAFF and APRIL mRNAs and proteins were detected in B-CLL leukemic cells and normal blood or tonsil-derived B lymphocytes. Yet, in contrast to normal B lymphocytes, BAFF and APRIL were expressed at the membranes of leukemic cells. Adding soluble BAFF or APRIL protected B-CLL cells against spontaneous and drug-induced apoptosis and stimulated NF-kappaB activation. Conversely, adding soluble BCMA-Fc or anti-BAFF and anti-APRIL antibodies enhanced B-CLL apoptosis. Moreover, a soluble form of BAFF was detected using surface-enhanced laser desorption/ionization-time-of-flight mass spectrometry (SELDI-TOF MS) in the sera of B-CLL patients but not of healthy donors. Taken together, our results indicate that B-CLL cells can be rescued from apoptosis through an autocrine process involving BAFF, APRIL, and their receptors. Inhibiting BAFF and APRIL pathways may be of therapeutic value for B-CLL treatment. 相似文献
985.
Chiral biphenyl diphosphines for asymmetric catalysis: stereoelectronic design and industrial perspectives 下载免费PDF全文
Jeulin S de Paule SD Ratovelomanana-Vidal V Genêt JP Champion N Dellis P 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(16):5799-5804
Two original chiral diphosphines, SYNPHOS and DIFLUORPHOS, have been synthesized on multigram scales. Their steric and electronic profiles have been established in comparison with the commonly used 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl and 6,6'-dimethoxy-2,2'-bis(diphenylphosphino)-1,1'-biphenyl ligands. A screening study of the four ligands in Ru(II)-catalyzed asymmetric hydrogenation of prochiral ketones and olefins has been performed. It revealed that the stereoelectronic features of the ligand and the substrate deeply influenced the enantioselectivities obtained in asymmetric hydrogenation, SYNPHOS and DIFLUORPHOS being fully complementary in terms of enantioselectivity for this reaction. 相似文献
986.
987.
Guillemin F Durieux S Daurès JP Lafuma A Saraux A Sibilia J Bourgeois P Sany J 《The Journal of rheumatology》2004,31(7):1297-1304
OBJECTIVE: The economic impact of rheumatoid arthritis (RA) is substantial, but most studies provide cost estimates specific to a US population. We performed a cost-of-illness analysis of patients with RA for French society. METHODS: A cross-sectional study among rheumatologists in 148 hospitals in France was conducted between November and December 2000. Data were collected on health resource consumption associated with RA (treatments, medical devices, physician visits, examinations, hospitalization, other health professional care) during the previous 12 months. Direct costs and social costs were evaluated for 1109 RA patients. The relation of costs to disease activity and severity was analyzed. RESULTS: The annual direct cost of RA per patient was over euro4000. The costs due to hospitalizations represented around 60% of the costs. The major reason for hospitalization was acute care for RA in a rheumatic disease ward. Patients visited a physician an average of 13 times during the 12 months, 7.7 +/- 8.6 visits to an office-based physician and 5.1 +/- 4.4 visits to a hospital-based physician. Among them, 37% of patients were receiving at least one disability pension (16.7%) or sick-leave allowance (11.9%), with an estimated cost of euro7328 per patient. The mean annual budget per patient was euro2742. Medical and social costs increased in patients with severe disease (2 times), longer disease duration since diagnosis (more than double for patients with a history longer than 10 yrs vs patients with less than 2 yrs), active disease (1.4 times), and functional status (4 times more for American College of Rheumatology class IV than for class I). CONCLUSION: Direct costs represented 59% of the total costs for patients with active RA and 57% for patients with severe RA. Social costs represented 41% of the total costs on average. 相似文献
988.
989.
Malphettes M Carcelain G Saint-Mezard P Leblond V Altes HK Marolleau JP Debré P Brouet JC Fermand JP Autran B 《Blood》2003,101(5):1891-1897
Immunodeficiency following autologous CD34+-purified peripheral blood stem cell (PBSC) transplantation could be related to T-cell depletion of the graft or impaired T-cell reconstitution due to thymus irradiation. Aiming to assess the role of irradiated thymus in T-cell repopulation, we studied 32 adults with multiple myeloma, randomly assigned to receive high-dose therapy including total body irradiation (TBI) followed by autologous transplantation with either unselected or CD34+-selected PBSCs. The median number of reinfused CD3+ cells was lower in the selected group (0.03 versus 14 x 10(6)/kg; P =.002). Lymphocyte subset counts were evaluated from month 3 to 24 after grafting. Naive CD4+ T cells were characterized both by phenotype and by quantification of T-cell receptor rearrangement excision circles (TRECs). The reconstitution of CD3+ and CD4+ T cells was significantly delayed in the CD34+-selected group, but eventually led to counts similar to those found in the unselected group after month 12. Mechanism of reconstitution differed, however, between both groups. Indeed, a marked increase in the naive CD62L+CD45RA+CD4+ subset was observed in the selected group, but not in the unselected group in which half of the CD45RA+CD4+ T cells appear to be CD62L-. Age was identified as an independent adverse factor for CD4+ and CD62L+CD45RA+CD4+ T-cell reconstitution. Our results provide evidence that infusing PBSCs depleted of T cells after TBI in adults delays T-cell reconstitution but accelerates thymic regeneration. 相似文献
990.
Maité Garrouste-Orgeas Elie Azoulay Stéphane Ruckly Carole Schwebel Etienne de Montmollin Jean-Pierre Bedos Bertrand Souweine Guillaume Marcotte Christophe Adrie Dany Goldgran-Toledano Anne-Sylvie Dumenil Hatem Kallel Samir Jamali Laurent Argaud Michael Darmon Jean-Ralph Zahar J. F. Timsit 《Infection》2018,46(5):669-677