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131.
RR Klont CA Eggink AJ Rijs P Wesseling PE Verweij 《Clinical infectious diseases》2005,40(12):e110-e112
A case of invasive Fusarium keratitis in a previously healthy male patient was treated successfully with cornea transplantation and systemic and topical voriconazole after treatment failure with topical amphotericin B and systemic itraconazole. Topical voriconazole was well tolerated, and, in conjunction with the oral administration, it resulted in a high level of the drug in the anterior chamber of the eye (which was 160% of the plasma drug level). 相似文献
132.
Physiologic regulation and tissue localization of renal erythropoietin messenger RNA 总被引:7,自引:0,他引:7
Although erythropoietin (Epo) is produced primarily by the kidneys in response to hypoxia, the precise cell type(s) and mechanisms by which these cells regulate production are poorly understood. In the experiments we report, the kinetics of renal Epo production in response to acute hypoxia and the intrarenal localization of cellular Epo synthesis were studied at the level of Epo mRNA. Erythropoietin mRNA expression was determined by Northern blot analysis of rat kidney RNAs using a probe derived from the mouse Epo gene. Renal Epo mRNA content increased as early as 1 hour after initiation of hypoxia and continued to accumulate during 4 hours of stimulation. Discontinuation of the hypoxic stimulus resulted in rapid decay of mRNA levels. Kidney and plasma Epo levels measured by radioimmunoassay paralleled, with respective lag times, the changes in renal Epo mRNA content, suggesting that Epo production in response to acute hypoxia represents de novo synthesis and is regulated by changes in Epo mRNA. Northern blot analysis of RNAs extracted from separated glomerular and tubular tissue fractions revealed Epo mRNA in the tubular fraction, whereas glomerular tissue did not contain Epo mRNA. Thus, the site of cellular Epo synthesis is located in the renal tubule or its interstitium and not in the glomerular tuft. 相似文献
133.
Protein C, an antithrombotic protein, is reduced in hospitalized patients with intravascular coagulation 总被引:7,自引:0,他引:7
Activated protein C is a potent anticoagulant and profibrinolytic enzyme that can be derived from the vitamin-K-dependent serine protease zymogen, protein C, by the action of thrombin. Protein C antigen concentration was determined in plasmas from normals (n = 40) and from 38 patients with intravascular coagulation as evidenced by positive FDP (greater than micrograms/ml). Plasma protein C was 4 micrograms/ml in normals and was significantly depressed (less than 2 SD below the mean of normals) in 19 of the 38 patients. Of 15 patients with suspected intravascular coagulation but normal FDP, protein C was decreased in 5 individuals; 3 of these 5 patients had liver disease. Based on these results, we suggest that extensive activation of the coagulation system in vivo causes a significant consumption of protein C, presumably due to its activation by thrombin and subsequent clearance. 相似文献
134.
Eosinophil functions can be modulated by several cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin- 3 (IL-3), and IL-5. We have investigated the modulatory role of these cytokines on the interaction of human eosinophils with opsonized particles (serum-treated zymosan [STZ]). Addition of STZ to eosinophils isolated from the peripheral blood of normal human donors resulted in an interaction of the STZ particles with only 15% to 25% of the cells. Treatment of the eosinophils with GM-CSF, IL-3, or IL-5 strongly enhanced both the rate of particle binding and the percentage of eosinophils binding STZ. The effect of the cytokines is most likely mediated by a change in affinity of the complement receptor type 3 (CR3) on the eosinophils for the complement fragment iC3b on the STZ particles. This is indicated by the observation that (1) the effect of the cytokines on STZ binding was prevented by a monoclonal antibody against the iC3b-binding site on CR3 and (2) the enhanced binding was already apparent before upregulation of CR3 on the cell surface was observed. In a previous study, similar results were obtained with platelet-activating factor (PAF)-primed eosinophils. Because we found that the cytokines strongly enhanced the STZ-induced PAF synthesis, we investigated the role of both released PAF and cell-associated PAF in the priming phenomenon by the cytokines. Cytokine priming appeared to be largely independent of the synthesis of PAF. 相似文献
135.
Jessurun GA Hautvast RW DeJongste MJ Meyler WJ van Boven AJ Crijns HJ 《The Journal of invasive cardiology》1999,11(7):435-438
Patients with symptomatic small vessel coronary artery disease may be inadequate candidates for revascularization procedures. They may suffer from refractory angina, which does not respond to maximal anti-anginal drug therapy. In addition to patients with end stage coronary artery disease and syndrome X, this newly defined group of subjects with an isolated stenosis of a small coronary artery may benefit from electrical neurostimulation. We describe two patients with intractable angina caused by a significant narrowing of a diagonal branch. This treatment modality should be considered as an alternative method for unsatisfactory revascularization procedures. 相似文献
136.
Expression of bcl-xL can confer a multidrug resistance phenotype 总被引:14,自引:3,他引:14
It has been suggested that genes that regulate apoptotic cell death may play an important role in determining the sensitivity of tumor cells to chemotherapy. We have recently cloned a member of the bcl-2 family, bcl- x. To test whether bcl-XL expression affects the sensitivity of tumor cells to chemotherapy, we have created stable cell lines overexpressing bcl-XL and have tested these cells for resistance to cell death induced by metabolic inhibitors and chemotherapeutic agents. Bcl-XL expression dramatically reduces the cytotoxicity of bleomycin, cisplatin, etoposide, vincristine, hygromycin B, and mycophenolic acid for up to 4 days in culture. Bcl-XL does not prevent cells from undergoing cell cycle arrest in response to these drugs, but rather prevents treated cells from undergoing apoptosis. Cell-cycle analysis on cells treated with the chemotherapeutic agents bleomycin, cisplatin, etoposide, and vincristine, show that the drugs cause growth arrest in different positions within the cell cycle. Bcl-XL expressing cells treated with chemotherapeutic drugs retain their proliferative ability after the drugs are removed. Interestingly, vincristine-treated cells expressing bcl-XL become polyploid after drug removal. These data show that bcl-XL protects cells from a wide variety of apoptotic stimuli, acts in multiple positions within the cell cycle, and confers a multidrug resistance phenotype. The ability of bcl-XL to prevent apoptotic cell death in response to chemotherapy-induced DNA damage and cell-cycle arrest may contribute to the accumulation of chromosomal aberrations within tumors. The expression of bcl-XL in tumor cells is likely to be an important indicator of chemotherapeutic efficacy. 相似文献
137.
Stephens RW; Golder JP; Fayle DR; Hume DA; Hapel AJ; Allan W; Fordham CJ; Doe WF 《Blood》1985,66(2):333-337
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone. 相似文献
138.
The purpose of the present study was to investigate a possible seasonal
pattern in various clinical and laboratory manifestations in a group of
systemic lupus erythamatosus (SLE) patients. One hundred and five SLE
patients were followed up during a 4 yr period. Data on each of the
clinical and laboratory variables examined, as well as the results of the
disease activity index (SLEDAI), were plotted against the month during
which they were obtained. Photosensitivity was the only variable to show a
seasonal pattern, having higher scores during the summer months (1.04 +/-
0.16 in July vs 0.58 +/- 0.12 in December). We were unable to show seasonal
patterns in any of the other variables examined. As a group, SLE patients
do not show any significant seasonal pattern in disease manifestations and
activity, except for photosensitivity. However, such a pattern may exist
for the individual patient.
相似文献
139.
An undifferentiated variant derived from the human acute myelogenous leukemia cell line (KG-1) 总被引:21,自引:7,他引:21
A variant subline (KG-1a) of the human acute myelogenous leukemia (AML) cell line (KG-1) has been isolated. The cells retain the same constitutive markers as the parent line, including HLA antigens, isoenzymes, and karyotype. The cells from the subline are morphologically and histochemically undifferentiated blast cells, while the parent cells and several of its clones are at the myeloblast and promyelocyte stages of development. The variant cells do not respond to colony-stimulating factor (CSF), and they do not express the human la antigen, nor a recently characterized AML antigen. The parent KG-1 cells are stimulated to proliferate in the presence of CSF and the cells express the la and AML antigen. Variant AML cell lines, such as KG-1a, will be useful in vitro models for investigating cellular response to CSF and for studying antigen expression in leukemic cells. 相似文献
140.