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851.
852.
RR Allingham JL Wiggs MA De La Paz D Vollrath DA Tallett B Broomer KH Jones EA Del Bono J Kern K Patterson JL Haines MA Pericak-Vance 《Canadian Metallurgical Quarterly》1998,39(12):2288-2295
PURPOSE: To examine families ascertained for late-onset primary open-angle glaucoma (POAG) to determine mutations in the gene coding for myocilin. METHODS: The diagnosis of late-onset POAG was defined as age at diagnosis more than 35 years, intraocular pressure (IOP) 22 mm Hg or more in both eyes or 19 mm Hg or more while the patient was taking two glaucoma medications, glaucomatous optic neuropathy in both eyes, and visual field loss consistent with optic nerve damage in at least one eye of the proband. Two of three criteria were required in other family members. DNA from all families was screened for polymorphisms in myocilin using single-strand conformation polymorphism analysis. All polymorphisms were sequenced for mutations. RESULTS: Eighty-three affected people in 29 families with late-onset POAG were screened for mutations. Three mutations, two novel missense (Thr377Met and Glu352Lys) and one nonsense (Gln368STOP), were identified. The missense mutations did not segregate with the disease phenotype in these families. The nonsense mutation was found in 3 of 29 unrelated families with POAG. All affected family members and 8 of 12 in whom glaucoma was suspected had the Gln368STOP mutation. All people with this mutation had elevated IOP, and 78% had POAG by age 70. CONCLUSIONS: Three mutations were identified in the gene coding for myocilin in families with late-onset POAG. Of these, the Gln368STOP mutation was highly associated with the development of glaucoma. All people with this mutation had glaucoma or elevated IOP by age 70. In the United States, the Gln368STOP mutation in myocilin is strongly associated with the development of late-onset POAG. However, factors in addition to the presence of this mutation seem to play a role in the development of ocular hypertension and glaucoma in these families. 相似文献
853.
水系统地板辐射采暖的干式做法 总被引:8,自引:0,他引:8
介绍了低温地板辐射采暖水系统的干式做法适用范围。提出了干式系统做法中应注意的一些问题和解决办法。对地板采暖干式做法有一定的指导意义。 相似文献
854.
855.
A. Ordine A. Boiano P. Parascandolo A. D'Onofrio L. Campajola A. De Rosa G. Inglima M. La Commara V. Roca M. Romano M. Romoli D. Pierroutsakou M. Sandoli F. Terrasi 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1997,390(3):366-374
A data transfer problem using FERA modules was found in a heavy ion nuclear physics experiment. The source of the problem was spotted in the handling of some signals on the FERA control bus. A modification of this handling is proposed and performed by means of a new CAMAC-FERA control module, the EBOFERA. Furthermore, this module has a number of useful features like the master gate and clear signals handling, event tagging, pattern unit and event counter. 相似文献
856.
F Parazzini E Bidoli S Franceschi D Schinella F Tesio C La Vecchia R Zecchin 《Canadian Metallurgical Quarterly》1996,50(5):519-523
A scheme for purification of hyaluronidase from Staphylococcus aureus 0-15 that allows to produce a 550-fold-purified preparation with a high specific activity was developed. Hyaluronidase was found to consist of two molecular forms with different molecular weights. Staphylococcus hyaluronidase referred to as a complex preparation and its molecular forms have action optimum at pH 5.0-7.2 and at a temperature between 30 and 37 degrees C. The enzymes were highly specific to their substrate: they catalyzed the depolimerization of hyaluronic acid but did not split the other glycosaminoglycans. 相似文献
857.
A typical static VAr shunt compensator has been analyzed so that the step response and steady-state errors can be identified. The results show that the steady-state error is dependent upon the error in the measurement of the currents' phase alone. They also show that an unstable condition can occur, though it should rarely arise in practice. All the theory was verified on a low power (240 V, 3 A) system 相似文献
858.
The stress and strain radial distributions within the minimum cross section of a tensile specimen undergoing necking, calculated
with the Bridgman method, differ, in some cases substantially, from finite-element method (FEM) results. Analyses of the possible
reasons for these differences show that an important role is played by the uniformity of the strain distribution assumed by
Bridgman. In this study, three types of steels were subjected to tensile testing, and FEM analyses were performed to simulate
the experimental trails. The comparison of the experimental and numerical results indicates the magnitude of the approximations
intrinsic to the Bridgman method. Through further FEM analyses, it was possible to isolate, in qualitative terms, the influence
of the Bridgman approximation from that of the void growth. This has been made by applying the Bridgman formulation to the
proper FEM output data and comparing the resulting curves to the curves used as material input for the same analyses. Finally,
it was found that, over a certain range of hardening materials, the correction of the true curve depends only on the necking
strain, within the same error level given by the Bridgman method. This means that, once the corrective law common to many
materials is found, then the correction procedure is substantially improved in terms of effort and time consumption, because
it does not need the necking-curvature measurements required by the Bridgman method. 相似文献
859.
C Bromuro R La Valle S Sandini F Urbani CM Ausiello L Morelli C Fé d'Ostiani L Romani A Cassone 《Canadian Metallurgical Quarterly》1998,66(5):2154-2162
The 70-kDa recombinant Candida albicans heat shock protein (CaHsp70) and its 21-kDa C-terminal and 28-kDa N-terminal fragments (CaHsp70-Cter and CaHsp70-Nter, respectively) were studied for their immunogenicity, including proinflammatory cytokine induction in vitro and in vivo, and protection in a murine model of hematogenous candidiasis. The whole protein and its two fragments were strong inducers of both antibody (Ab; immunoglobulin G1 [IgG1] and IgG2b were the prevalent isotypes) and cell-mediated immunity (CMI) responses in mice. CaHsp70 preparations were also recognized as CMI targets by peripheral blood mononuclear cells of healthy human subjects. Inoculation of CaHsp70 preparations into immunized mice induced rapid production of interleukin-6 (IL-6) and tumor necrosis factor alpha, peaking at 2 to 5 h and declining within 24 h. CaHsp70 and CaHsp70-Cter also induced gamma interferon (IFN-gamma), IL-12, and IL-10 but not IL-4 production by CD4+ lymphocytes cocultured with splenic accessory cells from nonimmunized mice. In particular, the production of IFN-gamma was equal if not superior to that induced in the same cells by whole, heat-inactivated fungal cells or the mitogenic lectin concanavalin A. In immunized mice, however, IL-4 but not IL-12 was produced in addition to IFN-gamma upon in vitro stimulation of CD4+ cells with CaHsp70 and CaHsp70-Cter. These animals showed a decreased median survival time compared to nonimmunized mice, and their mortality was strictly associated with organ invasion by fungal hyphae. Their enhanced susceptibility was attributable to the immunization state, as it did not occur in congenitally athymic nude mice, which were unable to raise either Ab or CMI responses to CaHsp70 preparations. Together, our data demonstrate the elevated immunogenicity of CaHsp70, with which, however, no protection against but rather some enhancement of Candida infection seemed to occur in the mouse model used. 相似文献
860.
L Baldini M Blini A Guffanti V Fossati M Colombi ML La Targia F Bertoni A Alietti A Neri G Bertoni 《Canadian Metallurgical Quarterly》1998,9(7):779-781
BACKGROUND: The aim of this study was to assess clinicopathological characteristics and outcome in a series of primary ocular adnexal lymphomas (POALs). PATIENTS AND METHODS: Nineteen patients with localised (stage IE) POAL were followed for a median of 96 months (24-156). The diagnosis was based on surgical biopsies followed by immunohistochemistry in 16 cases or fine-needle aspiration followed by immunocytophenotypic analysis in three cases. Twelve patients were treated with local radiotherapy (RT), five with chemotherapy (CT), and two refused further therapy after apparently radical tumour removal achieved by the diagnostic excisional biopsy. RESULTS: The histological and immunological pattern was consistent with a diagnosis of MALT-type lymphoma (11 cases), follicular center non-Hodgkin's lymphoma (three cases). a large-cell variant of Burkitt's lymphoma (one case), and large-cell transformed MALT lymphoma (one case). Low-grade lymphoma was diagnosed in the three cases which underwent fine-needle aspiration biopsy. All of the patients achieved and maintained complete remission except for those treated with surgical excision alone (two MALT conjunctival lymphoma cases): one of these relapsed locally, the other experienced the systemic spread of a transformed diffuse large-cell lymphoma and died 72 months after diagnosis. The side effects consisted of two cases of RT-related cataract after 52 and 72 months. CONCLUSIONS: Regardless of histology, prognosis was excellent when surgery plus RT was adopted, and CT seems to be a valid alternative to RT. Surgery alone may be sub-optimal. 相似文献