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471.
Clinical significance of autoantibodies against neutrophil cytoplasmic components in patients with renal disease 总被引:1,自引:0,他引:1
The diagnostic significance of anticytoplasmic autoantibodies (ANCA) was studied in 71 renal patients. The ANCA test was positive in 67% of patients with Wegener's granulomatosis (WG), in 35% of those with a simultaneous renal and respiratory tract disease but not diagnosed as WG and in 22% of patients with a renal disease associated with unspecific collagenosis/vasculitis. Among WG patients ANCA positivity clearly correlated with the presence of active renal disease. Interestingly, both ANCA-positive and -negative patients were encountered in the group with acute renal failure and acute extracapillary glomerulonephritis associated with diffuse pulmonary infiltrates. The diagnostic and clinical significance of the ANCA test in these cases remains for the present obscure. In the majority of the ANCA-positive renal patients with respiratory tract abnormalities, the antibodies showed diffuse cytoplasmic staining and were mostly of the IgG class, of both IgG and IgM classes in some cases and of IgG, IgM and IgA classes in 1 patient. In patients with unspecific vasculitis/collagenosis the level of ANCA was rather low, and the distribution of different isotypes resembled that of patients with respiratory symptoms. A certain isotype of ANCA or staining pattern did not mark out any clinicopathologic subgroup among the patients. Our findings indicate that the clinical picture of ANCA-positive patients varies considerably and the ANCA test may not be as specific a marker of WG as previously suggested. 相似文献
472.
Awoniyi O. Awonuga Nicola Dean Jamal Zaidi Rudiger U. Pittrof Jinan S. Bekir Seang-Lin Tan 《Journal of assisted reproduction and genetics》1996,13(4):293-297
Aim: Our aim was to compare the outcome in subsequent frozen embryo replacement cycles in four groups of patients who had elective cryopreservation of all their embryos because they were considered to be at increased risk of developing severe ovarian hyperstimulation syndrome.
Design: Sixty-two (91%) of 68 IVF cycles (68 patients) in which elective cryopreservation of all embryos was performed were analyzed. All patients continued on the GnRH agonist, buserelin, after oocyte recovery until the onset of vaginal bleeding. Frozen embryo replacement occurred in a hormone replacement cycle that started either on day 3 of the withdrawal bleed (group I;N=15) or after serum estradiol levels had fallen to <100 pmol/L (group II;N=16). The other patients commenced a frozen embryo replacement cycle several months later in either a hormone replacement (group III;N=15) or a natural (group IV;N=16) cycle.
Results: Two patients developed severe ovarian hyperstimulation syndrome. There were no significant differences among the four groups regarding demographic variables, the dose of hMG used, and the clinical outcome. There was a higher but not significantly different clinical pregnancy rate in group I (26.7%), compared to group II (12.5%), group III (13.3%), and group IV (18.8%).
Conclusions: Several options exist for the timing and protocol used for frozen embryo replacement in patients who had elective cryopreservation for the prevention of ovarian hyperstimulation syndrome, none of which was found to be clearly superior in this observational report.Presented at the 1994 Annual Conference of the American Fertility Society. 相似文献
473.
Plasmapheresis was used to correct blood lipid composition in patients with angina at rest and angina of effort (functional classes 3-4). In addition to a drop in total cholesterol and triglycerides, cholesterol in low and very-low-density lipoproteins fell abruptly, while high-density-lipoprotein cholesterol, on the contrary, increased considerably. Clinical improvement of the patients was also recorded. 相似文献
474.
475.
476.
A serous retinal detachment and choroidal hemorrhagic infiltration developed in a 17-year-old girl with acute lymphoblastic leukemia one year after cessation of therapy without concurrent bone marrow (BM) or central nervous system relapse. A choroidal biopsy through a sclerotomy with simultaneous release of subretinal fluid revealed no malignant cells. Accordingly, she was treated with prednisone, topical corticosteroid and atropine with normalisation of vision and clinical findings. Five months later the retinal detachment and choroidal infiltration recurred. In order to re-attach the retina once more and obtain a representative choroidal biopsy, a pars plana vitrectomy followed by a retinotomy with removal of subretinal tissue was done revealing leukemic infiltration of the choroid. Simultaneously a BM relapse was diagnosed. 相似文献
477.
478.
The inhibitory action of the major constituent of Sebastiania schottiana (Euphorbiaceae), 2-hydroxy-4,6-dimethoxyacetophenone (xanthoxyline) on contractions induced by agonists and electrical stimulation of smooth and cardiac muscle preparations was analysed. Xanthoxyline (30 to 300 microM) inhibited contractions of the rat uterus, guinea-pig ileum, and urinary bladder induced by several agonists in a non-competitive, non-selective, concentration-related manner, with the IC50's ranging between 47 and 190 microM. Twitches evoked by electrical-stimulation of strips of guinea-pig longitudinal ileum, urinary bladder, dog ureter, and rat left atrium were also inhibited dose-dependently by cumulative additions of xanthoxyline (IC50's between 50 and 480 microM). Xanthoxyline was found to be a potent inhibitor of spontaneous contractions of the circular smooth muscle layer of the dog ureter, yielding an IC50 of 54 microM. Repeated washing of all preparations completely reversed the inhibitory effects of xanthoxyline. Therefore, it appears that xanthoxyline induces a direct and non-selective inhibition of contractions triggered by agonists or electrical stimulation of smooth and cardiac muscle preparations. The elucidation of the mechanism(s) by which xanthoxyline induced muscle relaxation requires further investigations. 相似文献
479.
480.
K W Zuurbier A R Bakkenist R H Fokkens N M Nibbering R Wever A O Muijsers 《Biochemical pharmacology》1990,40(8):1801-1808
The chlorinating activity of myeloperoxidase, isolated from human polymorphonuclear neutrophils, was inhibited by the non-steroidal anti-inflammatory drug diclofenac (Voltaren). The concentration of diclofenac needed for 50% inhibition was 20 microM, a value comparable with IC50 values found for other drugs. Diclofenac did not react with HOCl nor with H2O2 but was oxidized in the presence of myeloperoxidase and H2O2 to an orange-coloured unstable product. The rate of oxidation was proportional to the enzyme concentration and to the concentration of diclofenac. but independent of the H2O2 concentration. Presumably both Compound I and Compound II, two intermediates formed during the reaction cycle of myeloperoxidase with H2O2 are able to oxidize diclofenac. In these redox reactions, the active short-living Compound I is reduced to Compound II, thereby inhibiting the chlorinating activity of the enzyme. Analysis by Fast Atom Bombardment mass spectrometry showed that in the presence of H2O2 myeloperoxidase oxidizes diclofenac to dihydroxyazobenzene. 相似文献