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91.
Thiago Silva Torres Valeria Cavalcanti Rolla 《The international journal of tuberculosis and lung disease》2006,10(11):1302; author reply 1302-1302; author reply 1303
92.
Ana C Mendes M Madalena Caldeira Claudia Silva Shawn C Burgess Matthew E Merritt Filipe Gomes Cristina Barosa Teresa C Delgado Fatima Franco Pedro Monteiro Luis Providencia John G Jones 《Magnetic resonance in medicine》2006,56(5):1121-1125
Menthol glucuronide was isolated from the urine of a healthy 70-kg female subject following ingestion of 400 mg of peppermint oil and 6 g of 99% [U-(13)C]glucose. Glucuronide (13)C-excess enrichment levels were 4-6% and thus provided high signal-to-noise ratios (SNRs) for confident assignment of (13)C-(13)C spin-coupled multiplet components within each (13)C resonance by (13)C NMR. The [U-(13)C]glucuronide isotopomer derived via direct pathway conversion of [U-(13)C]glucose to [U-(13)C]UDP-glucose was resolved from [1,2,3-(13)C(3)]- and [1,2-(13)C(2)]glucuronide isotopomers derived via Cori cycle or indirect pathway metabolism of [U-(13)C]glucose. In a second study, a group of four overnight-fasted patients (63 +/- 10 kg) with severe heart failure were given peppermint oil and infused with [U-(13)C]glucose for 4 hr (14 mg/kg prime, 0.12 mg/kg/min constant infusion) resulting in a steady-state plasma [U-(13)C]glucose enrichment of 4.6% +/- 0.6%. Menthol glucuronide was harvested and glucuronide (13)C-isotopomers were analyzed by (13)C NMR. [U-(13)C]glucuronide enrichment was 0.6% +/- 0.1%, and the sum of [1,2,3-(13)C(3)] and [1,2-(13)C(2)]glucuronide enrichments was 0.9% +/- 0.2%. From these data, flux of plasma glucose to hepatic UDPG was estimated to be 15% +/- 4% that of endogenous glucose production (EGP), and the Cori cycle accounted for at least 32% +/- 10% of GP. 相似文献
93.
Catarina Gonzalez da Silva Karl Magnus Petersson Luís Faísca Martin Ingvar Alexandra Reis 《Journal of clinical and experimental neuropsychology》2004,26(2):266-277
Semantic verbal fluency tasks are commonly used in neuropsychological assessment. Investigations of the influence of level of literacy have not yielded consistent results in the literature. This prompted us to investigate the ecological relevance of task specifics, in particular, the choice of semantic criteria used. Two groups of literate and illiterate subjects were compared on two verbal fluency tasks using different semantic criteria. The performance on a food criterion (supermarket fluency task), considered more ecologically relevant for the two literacy groups, and an animal criterion (animal fluency task) were compared. The data were analysed using both quantitative and qualitative measures. The quantitative analysis indicated that the two literacy groups performed equally well on the supermarket fluency task. In contrast, results differed significantly during the animal fluency task. The qualitative analyses indicated differences between groups related to the strategies used, especially with respect to the animal fluency task. The overall results suggest that there is not a substantial difference between literate and illiterate subjects related to the fundamental workings of semantic memory. However, there is indication that the content of semantic memory reflects differences in shared cultural background--in other words, formal education--, as indicated by the significant interaction between level of literacy and semantic criterion. 相似文献
94.
M E Camargo S M da Silva P G Leser C H Granato 《Revista do Instituto de Medicina Tropical de S?o Paulo》1991,33(3):213-218
For serologically characterizing a recent primary toxoplasma infection, the low avidity of IgG specific antibodies was studied. Avidity was evaluated as the decrease of IgG antibody titers in ELISA after treating plates with 6 M urea, as a dissociating solution of low avidity antigen-antibody complexes. Sixty nine serum samples were studied, presenting characteristic patterns of recent, transitional or chronic toxoplasmosis. Serological patterns were determined according to results of IgG and IgM immunofluorescence, IgM-capture, and hemagglutination tests. Twenty three serum samples from each of the referred patterns I, II and III were titrated. For chronic toxoplasmosis infections, which presented a serological pattern III, observed decrease of titers was 3% +/- 3%. For pattern I recent toxoplasmosis sera it was 34% +/- 12%, and for transition pattern II, 12% +/- 9%. Thus, a low avidity of IgG specific antibodies can be applicable for the diagnosis of a recent toxoplasmosis infection. 相似文献
95.
MD Charles D. Hummer III MD PhD Richard H. Rothman MD William J. Hozack 《The Journal of arthroplasty》1995,10(6)
Catastrophic failure of two zirconia—ceramic modular femoral heads occurred, despite the theoretical improved toughness of zirconia—ceramic relative to alumina—ceramic. This experience led the authors to return to cobalt—chromium as the metal of choice for articulation against polyethylene in total hip arthroplasty. 相似文献
96.
97.
Eric Vivier Antonio J. da Silva Melissa Ackerly Herbert Levine Christopher E. Rudd Paul Anderson 《European journal of immunology》1993,23(8):1872-1876
The CD16: ζ: γ receptor complex allows natural killer (NK) cells to recognize and eliminate antibody-coated target cells. Whereas the ectodomain of CD16 is the receptor for Fcγ domains of immunoglobulins, disulfide-linked homo- and heterodimers composed of ζ and γ are required for the cell surface expression, and signal transduction properties of the complex. Engagement of CD16 activates the tyrosine kinase pathway, which induces the tyrosine phosphorylation of several substrates, including the ζ subunit and the phospholipase C γ-1 and γ-2 isoforms. Here we show that CD 16 stimulation of either peripheral blood NK cells, leukemic NK cells, or Jurkat transformants expressing a CD16:ζ:γ receptor complex, results in the tyrosine phosphorylation of a 70 kDa ζ-associated protein (pp70). Similarly, a 70-kDa ζ-associated phosphoprotein in T cells has been shown to be a tyrosine kinase (ZAP-70). Peptide mapping analysis indicates that the 70-kDa ζ-associated phosphoproteins from T cells and NK cells are structurally indistinguishable. We conclude that the CD16:ζ:γ complex may use a ZAP-70-related non-receptor tyrosine kinase, in the CD16 signaling cascade leading to NK cell activation. 相似文献
98.
J N dos Santos A M e Silva P Alexandrino T Saldanha M O Carrageta E Ferreira F de Pádua 《The Netherlands journal of medicine》1991,38(5-6):212-216
Inherited defects of the natural coagulation inhibitors predispose patients to thrombosis. These disorders have similar clinical presentations with a strong family history of thrombosis, episodes of recurrent venous thromboembolism, beginning in early adulthood. We report a case of upper gastrointestinal bleeding in a patient with portal hypertension due to portal-vein thrombosis secondary to hereditary protein C deficiency, an association that has seldom been reported. 相似文献
99.
Arthur A. Beisang III M.D. Robert A. Ersek M.D. F.A.C.S. 《Aesthetic plastic surgery》1992,16(1):83-90
The development of small, textured implant particles suspended in a hydrogel has allowed for subdermal injection therapy to fill tissue defects. The microimplant particles were placed subdermally into the ears of white New Zealand rabbits in order to characterize the foreign body response and the permanence of the implant. Serial micrometer readings were performed on the implant sites to determine any change in thickness of the augmentation following baseline measurement. An initial increase in the thickness was noted approximately 20–30 days postimplantation, as expected. A stable thickness was noted for the remainder of the experiment. Serial histological sections were performed at irregular intervals from one week to one year. Histology demonstrated a mild foreign body response with collagen surrounding each individual microimplant particle. The response was stable after 30–40 days and has remained stable for over one year. It was determined that the histology demonstrated a Boros IA type, or nonimmunogenic, low-turnover foreign body reaction. 相似文献
100.