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71.
M Braun S Bracard J-C Huot J Roland L Picard 《Surgical and radiologic anatomy : SRA》1996,18(4):315-321
Summary The pons is covered by a rich venous network offering numerous vascular landmarks in MRI and during surgery. We present an original study of the veins as they appear on MR multiplanar scans after gadolinium IV injection. This prospective study is based on 40 consecutive patients with normal posterior fossa structures. One of the major venous collectors follows the pons: the superior petrosal v. was identified on MRI in 95% of our cases. Its hooklike extremity drains into the superior petrosal sinus. The inferior petrosal v. was never identifiable. The superficial pontine venous network are identified in 72.5% of cases in the axial plane and were organised in longitudinal and transverse collectors, whose MR aspects are presented here.
Les veines du pont. Anatomie sectionnelle en IRM
Résumé Le pont, enveloppé des citernes subarachnoïdiennes, est parcouru à sa surface par de nombreux vaisseaux qui constituent autant de points de repère topographiques en IRM que de rapports chirurgicaux. Nous présentons une étude de l'anatomie veineuse en coupe telle que l'IRM la révèle après injection de Gadolinium. Cette étude prospective comporte 40 patients indemmes de lésion de la fosse crânienne postérieure. Le pont est longé par un des collecteurs majeurs du tronc cérébral : la v. pétreuse supérieure, identifiée dans 95 % des cas. Elle se jette par un crochet caractéristique dans le sinus pétreux supérieur. La v. pétreuse inférieure n'a jamais été reconnue. Les vv. pontiques forment un réseau maillé visible dans 72,5 % des cas en coupes axiales et comportant des axes transversaux et longitudinaux dont les critères d'identification sont présentés selon le plan de coupe.相似文献
72.
Computers have gained rapid acceptance in general practice. A recent development has been the use of computers to run practice appointment systems. This study demonstrates the benefits of installing a computerized appointment system, with improved service for patients, and more efficient use of time by both doctors and receptionists. 相似文献
73.
To determine the effect of subject self-selection on the alpha-hypnotizability correlation, the correlations between volunteer and invited subject groups were compared. For 8 volunteers the correlation between baseline eyes-closed occipital alpha and the Harvard Group Scale of Hypnotic Susceptibility score was r=.72; for 12 invited subjects, that correlation was r=-.02. The significant difference in these correlations gives support to a previously published paper which hypothesized, on the basis of a literature review, that sampling modifications generated by subject self-selection were responsible for the occurrence of significant alpha-hypnotizability correlations. 相似文献
74.
Nguyen Khac F Waill MC Romana SP Radford-Weiss I Busson M Collonge-Rame MA Ribadeau-Dumas A Piffaut MC Daniel MT Davi F Merle-Béral H Berger R Arock M 《Cancer Genetics and Cytogenetics》2002,138(1):22-26
Two patients with Ph-positive chronic myelocytic leukemia in erythroblastic transformation and rearrangement of the short arm of chromosome 18 are reported. Fluorescence in situ hybridization studies showed that the 18p rearrangement resulted from translocation of the main part of chromosome 22 long arm to 18p, including BCR-ABL1 fusion. The 18p abnormality resulted, thus, in loss of 18p and duplication of BCR-ABL1 in both patients. The possible relation to the erythroblastic type of blastic phase is briefly discussed. In addition an apparently intact germline ABL1 gene was duplicated and inserted into chromosome 6 at band p21 in one of these patients. 相似文献
75.
Interaction of B7RP-1 with ICOS Negatively Regulates Antigen Presentation by B Cells 总被引:1,自引:0,他引:1
Stimulation of T cells through the T cell receptor is insufficient for optimal T cell activation. A second activation signal is necessary, being usually provided by the costimulatory molecule CD28. Recently, additional costimulatory pathways have been identified, including inducible costimulator (ICOS) and its ligand B7RP-1. We have examined the role of the B7RP-1/ICOS costimulatory pathway on antigen presentation by B cells, using the I-Ak and I-Ek-positive CH27 B cell line and several different T cell lines. We found that CH27 expressed B7RP-1 and PD-L1 whereas the T cell lines expressed ICOS and PD-1. In the presence of HEL, the T cell hybridomas C10 and 3A9 released IL-2, which is indicative of antigen-specific T cell activation by the CH27 cells. Unexpectedly, blocking antibodies for B7RP-1 and ICOS enhanced the IL-2 response in both T cells. As expected, an increase in the production of IL-2 was seen when blocking antibodies for PD-1 were used. Blocking with antibodies for I-Ak, CD28, B7.1, and B7.2 lead to a decrease in IL-2 production. Additionally we tested a Th1 and a Th2 T cell clone. Blockade of B7RP-1/ICOS lead to an increased IFN- response in Th1 cells (A.E7) and an increased IL-4 response in Th2 cells (D10.G4.1). Intracellular staining also showed an increase in cytokine production when the B7RP-1/ICOS pathway was blocked. In conclusion, the B7RP-1/ICOS pathway is negatively regulating T cell activation by B cells and may play a role similar to that of the PD-L1/PD-1 pathway. 相似文献
76.
Thierry Janssen MD Michel Petein MD Roland van Velthoven MD Patrick van Leer MD Marc Fourmarier MD Juan-Pablo Vanegas MD Andre Danguy PhD Claude Schulman MD Jean-Lambert Pasteels MD Robert Kiss PhD 《Human pathology》1996,27(12):1341-1347
The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors. 相似文献
77.
Roland Berger Josette Hillion Daniel Janvier Zhu Chen Annette Bussel 《Cancer Genetics and Cytogenetics》1993,70(2):125-126
A t(8;21)(q22;q22) without blood and bone marrow invasion by immature myeloid precursor cells occurred in a patient previously treated for polycythemia vera. The presence of a molecular rearrangement confirmed that the chromosomal abnormality was identical to that observed in acute leukemia with t(8;21). This case shows that the translocation, t(8;21), may occur in myelodysplasia and suggests that it can precede the appearance of overt leukemia. 相似文献
78.
79.
Improved replication of influenza viruses in embryonated chicken eggs (CE) permits increased vaccine production and availability. We investigated the growth properties of influenza B viruses in relation to specific mutations occurring after serial passage in CE. In serial passage experiments yielding high growth variants of B/Victoria/504/2000, mutations predicted to alter amino acid (AA) composition occurred only near the receptor-binding pocket of the hemagglutinins (HA) and in no other genes. Two B/Victoria/504/2000 high growth variants had the same AA substitutions in HA (R162M and D196Y), but the higher yield variant had a third substitution (G141E), which also altered antigenic characteristics. In a serial passage experiment yielding a high growth variant of B/Hong Kong/330/2001, mutations predicted to alter AA composition occurred only in PB2 and NP in domains predicted to relate to RNP formation and function. Our results indicate that adaptation of influenza B viruses to high-yield replication by serial passage in CE requires few mutations either in internal or external genes. Specific modifications of genes or a combination of genes could be used to optimize or create influenza B viruses for specific growth substrates. 相似文献
80.
Ferdinando Nicoletti Roberto di Marcou Wilma Barcelliniu Gaetano Magro Hans U. Schorlemmeru Roland Kurrleu Michele Lunettau Sebastiano Grasso Paola Zacconeu Pierluigi Meronif 《European journal of immunology》1994,24(8):1843-1847
We have evaluated the effects of a treatment with soluble interleukin-1 receptor (sIL-1R) in the accelerated model of autoimmune diabetes induced by cyclophosphamide (CY) in the non-obese diabetic (NOD) mouse. Prior to the CY challenge (350 mg/kg body weight), female euglycemic NOD mice were randomly divided into three groups (A–C). Groups B and C were treated daily from 1 day before to 13 days after the CY challenge with sIL-1R at doses of 0.2 and 2 mg/kg body weight. Group A was treated with PBS. By 2 weeks after CY administration, an acute form of autoimmune diabetes with glycosuria, hyperglycemia and severe insulitis occurred in the majority (13/20, 65%) of the control mice (group A). In contrast, repeated injections with sIL-1R protected NOD mice from insulin-dependent diabetes mellitus (IDDM) development in a dose-dependent fashion; the incidence of IDDM was 53.3% (8/15) in the mice treated with 0.2 mg/kg and only 6.7% (1/15) in those treated with 2 mg/kg. However, none of the doses of the sIL-1R reduced the extent of insulitis in NOD mice. Importantly, the anti-diabetogenic property of sIL-1R may not involve major T cell function impairment; accordingly, in parallel experiments, splenic lymphoid cells from NOD mice not challenged with CY, but treated with 2 mg/kg sIL-1R for 5 consecutive days showed a normal distribution of mononuclear cell subsets and maintained their capacity to secrete interferon-γ and IL-2 and to proliferate in response to polyclonal mitogenic stimulation with concanavalin A. 相似文献