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Ohne Zusammenfassung 相似文献
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An intraocular lens with a reversed optic and with haptics angulated forward presses the posterior capsule more posteriorly than other types of lenses. This position is thought to be important even in eyes that do not need intraocular lenses for optical reasons, such as eyes with high axial myopia (because of their increased tendency to postoperative retinal detachment) and eyes with postoperative capsular fibrosis. "Zero lenses" were implanted in seven eyes. The lenses had a convex posterior surface and a concave anterior surface which were parallel. The position of the posterior capsule, measured with ultrasound, was 4.9 mm to 5.8 mm (mean 5.5 mm) behind the anterior corneal surface. In two fellow eyes without a lens (after planned extracapsular cataract extraction), the posterior capsule was 4.1 mm and 4.3 mm behind the anterior corneal surface. 相似文献
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We have developed a highly sensitive cytolysis test, the fluorolysis assay, as a simple nonradioactive and inexpensive alternative to the standard 51Cr-release assay. P815 cells were stably transfected with a plasmid expressing the enhanced green fluorescent protein (EGFP) gene. These target cells were coated with or without cognate peptide or anti-CD3 Ab and then incubated with CD8(+) T cells to allow antigen-specific or nonspecific lysis. The degree of target cell lysis was measured using flow cytometry to count the percentage of viable propidium iodide(-) EGFP(+) cells, whose numbers were standardized to a reference number of fluorochrome-linked beads. By using small numbers of target cells (200-800 per reaction) and extended incubation times (up to 2 days), the antigen-specific cytolytic activity of one to two activated CD8(+) T cells of a CTL line could be detected. The redirected fluorolysis assay also measured the activity of very few (> or =6) primary CD8(+) T cells following polyclonal activation. Importantly, antigen-specific lysis by small numbers (> or =25) of primary CD8(+) T cells could be directly measured ex vivo. This exquisite sensitivity of the fluorolysis assay, which was at least 8-33-folds higher than an optimized 51Cr-release assay, allows in vitro and ex vivo studies of immune responses that would otherwise not be possible due to low CTL numbers or frequencies. 相似文献
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CD137 (ILA/4-1BB), expressed by primary human monocytes, induces monocyte activation and apoptosis of B lymphocytes 总被引:11,自引:0,他引:11
Human CD137 is a member of the tumor necrosis factor (TNF) receptor family and the homologue of murine 4-1BB. Recent studies have demonstrated that CD137 promotes accessory T cell activation, and regulates proliferation and survival of T lymphocytes. This study reports on the expression and function of CD137 in peripheral blood monocytes. While monocytes showed constitutive expression in 10 out of 18 healthy donors, CD137 was not expressed on resting T or B lymphocytes. Immobilized antibodies to CD137 markedly induced the production of IL-8 and TNF-alpha protein and mRNA, and led to inhibition of IL-10 expression by primary monocytes. Furthermore, cross-linking of CD137 on monocytes resulted in an increase of B lymphocyte apoptosis mediated by direct cell-cell contact of both cell populations. In conclusion, this study identified CD137 as a new receptor involved in monocyte activation by inducing a characteristic cytokine release profile. In addition, CD137 may play a role in monocyte-dependent control of B lymphocyte survival. 相似文献
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Deduced sequence of the bovine coronavirus spike protein and identification of the internal proteolytic cleavage site 总被引:8,自引:1,他引:8
The sequence of the spike (also called peplomer or E2) protein gene of the Mebus strain of bovine coronavirus (BCV) was obtained from cDNA clones of genomic RNA. The gene sequence predicts a 150,825 mol wt apoprotein of 1363 amino acids having an N-terminal hydrophobic signal sequence of 17 amino acids, 19 potential N-linked glycosylation sites, a hydrophobic anchor sequence of approximately 17 amino acids near the C terminus, and a hydrophilic cysteine-rich C terminus of 35 amino acids. An internal Lys-Arg-Arg-Ser-Arg-Arg sequence predicts a protease cleavage site between amino acids 768 and 769 that would separate the S apoprotein into S1 and S2 segments of 85690 and 65153 mol wt, respectively. Amino terminal amino acid sequencing of the virion-derived gp 100 spike subunit confirmed the location of the predicted cleavage site, and established that gp 120 and gp 100 are the glycosylated virion forms of the S1 and S2 subunits, respectively. Sequence comparisons between BCV and the antigenically related mouse hepatitis coronavirus revealed more sequence divergence in the putative knob region of the spike protein (S1) than in the stem region (S2). 相似文献
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BACKGROUND: MADRS cut-off scores for moderate and severe depression were estimated in relation to the Hamilton Depression Rating Scale (HAMD(17)) and the Clinical Global Impressions Scale (CGI). METHOD: HAMD(17), MADRS, and CGI ratings from patients with major depression (DSM-IV) were analyzed (N=85). Receiver operating characteristics (ROC) curves were applied. RESULTS: Mean age was 51.4+/-14.5 years, 69% were female. Mean MADRS scores were 23.4+/-13.2, HAMD(17), MADRS, and CGI scores were highly correlated (r>0.85; P<0.0001). Best separation between moderate and severe depression according to CGI criteria was achieved with a MADRS score of 31 (sensitivity 93.5%, specificity 83.3%). LIMITATIONS: Studies to validate severity gradations including DSM-IV or ICD-10 diagnostic severity categories are recommended. CONCLUSIONS: Empirically based MADRS cut-off scores to separate moderate from severe depression on the basis of HAMD(17) and CGI severity ratings in patients with major depression were yielded. 相似文献
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