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51.
52.
Macrophages, dendritic cells or B lymphocytes have been shownto play a major role in the presentation of soluble antigensto CD4+ T cells. In contrast, the capacity of these cells topresent particulate antigens such as bacterial or parasiticantigens to T cells remains controversial. To investigate thisquestion, well defined particulate antigens were prepared bycovalent linkage of proteins or peptides to 1 µm in diametersynthetic microspheres. The T cell immunogenicity of such particulateantigens was analyzed in vitro and in vivo. In vitro, a solubleprotein such as hen egg lysozyme (HEL) coupled to beads stimulateda strong proliferative T cell response of lymph node cells fromHEL-primed mice or of specific T cell hybridomas. HEL coupledto beads was presented to the specific T cell hybridomas bysplenocytes or by peritoneal macrophages, but not by lymphomaB cells. Immunization of mice with several different proteinantigens or with a synthetic peptide covalently linked to beadsinduced strong CD4+ T cell responses in the absence of adjuvant.The strong in vivo immunogenicity of proteins coupled to beadsdid not result from a non-specific adjuvant effect of beadssince covalent linkage of the antigen to beads was strictlyrequired to induce T cell responses in the absence of adjuvant.In vivo treatment by carrageenan showed that macrophages arerequired for the in vivo stimulation of T cell responses bythese particulate antigens. Thus, these results demonstratedthe role of phagocytic cells, especially macrophages, for invivo presentation of particulate antigens. These particulateantigens represent an interesting approach for the developmentof new vaccines, and for the in vivo analysis of the role ofvarious antigen presenting cells in T cell activation and differentiation. 相似文献
53.
54.
Tsutomu Ogata Peter Goodfellow Christine Petit Pierre Maroteaux Nobutake Matsuo 《American journal of medical genetics. Part A》1993,45(1):101-104
This is a follow-up report on a male patient with a 46, Y, r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean – 5.6 S.D.). © 1993 Wiley-Liss, Inc. 相似文献
55.
Incidence of post-lumbar puncture syndrome reduced by reinserting the stylet: a randomized prospective study of 600 patients 总被引:1,自引:0,他引:1
The post-lumbar puncture syndrome (PLPS) can best be explained by prolonged spinal fluid leakage owing to delayed closure
of a dural defect. Its incidence after spinal anaesthesia is much lower than after diagnostic lumbar puncture (LP). This difference
could be caused by a strand of arachnoid, which might enter the needle with the outflowing cerebrospinal fluid (CSF) during
diagnostic LP and upon removal of the needle be threaded back through the dura to produce prolonged CSF leakage. To find a
technique that further reduces the incidence of PLPS, this hypothesis was tested by evaluating the effect that reinserting
the stylet before removing the needle had on the incidence of PLPS. By reinserting the stylet to the tip of the needle, the
hypothesized strand would be pushed out, thereby reducing the frequency of PLPS. Sprotte’s “atraumatic needle” (21 gauge)
was used for LP. A total of 600 patients participated in the prospective study. They were randomized into two groups and questioned
about their complaints every day for up to 7 days after the LP. All LPs were performed by two experienced neurologists (T.B.,
M.S.). In 300 patients, the stylet was reinserted to the tip of the needle; in the other 300 it was not reinserted. Whereas
49 of the 300 patients without reinsertion developed PLPS, only 15 of the 300 patients with reinsertion did. This significant
difference (16.3 vs 5.0%, P < 0.005, chi square test) supports our hypothesis. On the basis of our results, we recommend reinserting the stylet before
removing the needle in order to reduce the incidence of PLPS.
Received: 30 September 1997 Received in revised form: 9 March 1998 Accepted: 20 March 1998 相似文献
56.
Das Blasenkarzinom ist der h?ufigste maligne Tumor des Harntraktes und macht 3,5% aller Krebstodesf?lle aus. Es ist eine Erkrankung
mit stark variierendem Erscheinungsbild, das einer differenzierten Diagnostik bedarf. Neben der prim?ren Erkrankung haben
die diagnostischen Ma?nahmen das Ziel, die Tumorkrankheit in ihrer Gesamtheit zu erfassen, mit Lokalisation des Prim?rtumors,
Bestimmung seines Stadiums und seines Differenzierungsgrades. Die Diagnostik unterscheidet zwischen uni- und multifokalem
Wachstum, weist ein evtl. begleitendes Carcinoma in situ oder eine Dysplasie nach, erfa?t eine lymphatische oder h?matogene
Dissemination und erkennt eine Wandüberschreitung des Tumors oder eine Metastasierung. Eine übersicht über die diagnostischen
Ma?nahmen gibt Tabelle 1. 相似文献
57.
Christian Prueter Benedikt Habermeyer Christine Norra Christoph M Kosinski 《Movement disorders》2003,18(6):712-713
Due to its low profile for extrapyramidal side-effects, quetiapine has become an alternative to clozapine in the treatment of dopamimetic psychosis in patients with Parkinson's disease (PD). We describe the case of a patient with PD who developed severe akathisia, a common complication with classical antipsychotics, with quetiapine. 相似文献
58.
In vivo induction of Ia expression in murine cornea after intravitreal injection of interferon-gamma
C R Brandt P B Knupfer G A Boush R E Gausas J W Chandler 《Investigative ophthalmology & visual science》1990,31(11):2248-2253
Intravitreal injection of interferon gamma (IFN-gamma) induces increased expression of Class II major histocompatibility complex (Ia) antigen expression on corneal endothelial cells and stromal fibroblasts. In contrast, IFN-gamma has no detectable effect on Ia antigen expression in epithelium. Induction of Ia antigen expression was rapid with increases detectable as early as 6-12 hours after a single injection of 1 x 10(5) units. Expression peaked at 24-48 hours and decreased to background levels by 120 hours. The Ia antigen expression increased in a dose-dependent manner, and IFN-gamma treatment also induced the synthesis of increased amounts of a 65-kilodalton (kD) protein in the cornea. Increased levels of this 65-kd protein are seen as early as 12 hours after treatment and can be induced with as little as 1 x 10(2) units of IFN-gamma. The function of the 65-kd protein is unknown. This model should be useful in studies on in vivo modulation of Ia antigen expression. 相似文献
59.
News for the Practitioner 相似文献
60.
The present article presents the future of clinical psychology board certification. With the increasing specialization in the field of professional psychology and the generic nature of state licensure, clinical psychology as a specialty will develop into a specialty area in a similar fashion as have specialties in medicine. A brief history of board certification in professional psychology by the American Board of Professional Psychology is reviewed and the process of becoming board certified in either clinical psychology or clinical child and adolescent psychology is discussed. 相似文献