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21.
Corneal endothelial cell loss after multiple vitreoretinal procedures and the use of silicone oil 总被引:4,自引:0,他引:4
BACKGROUND AND OBJECTIVE: Corneal decompensation and complications are a frequent cause of visual loss after vitreoretinal surgery. This paper presents data regarding endothelial cell loss in aphakic and pseudophakic silicone oil filled eyes when oil was retained for many months. This study updates our previous investigation on the subject. PATIENTS AND METHODS: The corneal endothelial cell count of 10 eyes of 10 consecutive patients who had undergone vitreoretinal surgery, including fluid-gas exchange and ultimately silicone oil placement, were obtained. The patients underwent an average of 2.7+/-0.9 vitreoretinal procedures before the final procedure which induced the placement of silicone oil in the vitreous cavity. All had inferior iridectomies. The endothelial cell density measurements were obtained an average of 1 year after silicone oil placement. In all eyes, the oil was felt necessary for long term tamponade and therefore was not removed. The cell density of the operated eye was compared to the fellow eye, none of which had undergone silicone oil placement. RESULTS: Both gas and retained silicone oil contribute to the loss of corneal endothelial cell density. The average endothelial cell loss in the 10 eyes with oil retained for an average of 10+/-12 months was 68.8 +/-31.4%, as compared to the fellow eye. The average cell loss was higher in the three eyes with silicone oil in the anterior chamber (range 44 to >95%). Pseudophakic eyes fared better, on average, than aphakic eyes (51.66+/-28% vs. 66.63+/-26.3%) with respect to cell loss. Five aphakic eyes and 1 pseudophakic eye developed corneal edema. CONCLUSIONS: Endothelial cell loss occurs after vitreoretinal surgery and is exacerbated by long term silicone oil retention. The corneal endothelial cell damage is probably cumulative from procedure to procedure. Endothelial cell loss may be pronounced in eyes without a physical barrier between the anterior segment and the vitreous cavity, and in eyes where oil migrates into anterior chamber. 相似文献
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Questionnaire data on about 1200 male twin pairs from the Registry at the Karolinska Institute, Stockholm, and on about 4000 male twin pairs from the Registry of the National Research Council, Washington, DC, have been used to study factors affecting angina pectoris. An operational definition of "angina pectoris" was developed from the questionnaire. In the available data, alcohol drinking, lack of exercise, frequent change of employer, low occupational adjustment and smoking are moderately but significantly related to angina among individuals (disregarding twin relationships) in both Sweden and the US. In monozygous US twin pairs discordant for the above variables, significantly different rates of angina appear only with alcohol drinking. In discordant dizygous US twin pairs, significantly different rates of angina appear with alcohol drinking and with low occupational adjustment. Of the independent variables only smoking and drinking are appreciably associated with each other. These findings suggest that alcohol drinking and to a lesser extent occupational adjustment are related to angina directly and not through their association with other factors such as age, genetic background, smoking, physical exercise and early environment. 相似文献
24.
Elin Lindhagen Pernille‐Julia Vig Hjarnaa Lena E. Friberg Scilla Latini Rolf Larsson 《Drug development research》2004,61(4):218-226
When a candidate drug enters clinical trials, decisions regarding dosing are mainly based on animal data. Occasionally, toxicity problems are faced in the clinic because of unexpected species differences in pharmacokinetics or pharmacodynamics between humans and preclinical species. Fludarabine and topotecan are examples of such drugs. In the first clinical trials of the new agent CHS 828, the maximum tolerated dose was reached earlier than expected from animal data. This paper discusses the issue of species differences in the development of anticancer drugs, and preclinical models for detection and quantification of such differences. Pharmacokinetic and hematological toxicity data of CHS 828 from studies in rats and humans are presented. In vitro sensitivity to CHS 828 and some established cytotoxic agents was measured in lymphocytes from humans and rats and in a panel of human and rodent cell‐lines. 10–100 times higher CHS 828 exposure was tolerated by rats than by patients. In both in vitro cell systems, CHS 828 showed higher potency in human cells compared to rodent cells. A species difference was evident also for fludarabine, but not for doxorubicin and cisplatin. CHS 828 pharmacokinetics were similar across species. In conclusion, the lower tolerance of CHS 828 in humans than in rats could be detected in vitro in cultures of peripheral lymphocytes. Preclinical studies of species differences could help the interpretation of in vivo effect studies as well as the choice of starting dose for clinical trials. We suggest peripheral lymphocytes from different species as a potential model system for such studies. Drug Dev. Res. 61:218–226, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
25.
W. Paul Dmowski Janina Michalowska Nasiruddin Rana Jan Friberg Elizabeth McGill-Johnson Linda DeOrio 《Journal of assisted reproduction and genetics》1997,14(3):139-144
Purpose: The purpose of this study was to evaluate the clinical effectiveness of subcutaneous estradiol pellets in donor oocyte recipients
with an inadequate endometrial response.
Methods: The subjects were 13 women with ovarian failure and a maximal endometrial thickness <10 mm on standard estrogen regimens,
as demonstrated during mock and/or prior oocyte donation cycles. They underwent pellet implantation (100–250 mg of estradiol)
6–13 weeks before oocyte donation.
Results: Maximal (mean ± SD) endometrial thickness was 8.7±1.5 mm on standard regimens, in contrast to 11.7± 1.8 mm on pellets, while
estradiol levels were 674±844 and 815±706 pg/ml, respectively. The estradiol:estrone ratio on pellets was >1. There was 1
pregnancy with early loss during 10 cycles on other estrogen regimens and 12 pregnancies during 19 cycles on pellets. The
pregnancy and implantation rates were, respectively, 63 and 27% on pellets and 41 and 14% on standard regimens in historical
controls.
Conclusions: We conclude that estradiol pellets after a single administration provide constant estradiol levels extending into the first
trimester of pregnancy, a physiologic estradiol:estrone ratio, and a better endometrial response than standard estrogen regimens.
Implantation and pregnancy rates are higher. This approach may be especially suitable for recipients with a poor endometrial
response.
Presented at the IXth World Congress on In Vitro Fertilization and Assisted Reproduction, Vienna, Austria, April 3, 1995,
and the 51st Annual Meeting of the American Society for Reproductive Medicine, Seattle, Washington, October 7–12, 1995. 相似文献
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28.
Long-term outcome in relation to renal sympathetic activity in patients with chronic heart failure. 总被引:1,自引:0,他引:1
Magnus Petersson Peter Friberg Graeme Eisenhofer Gavin Lambert Bengt Rundqvist 《European heart journal》2005,26(9):906-913
AIMS: Although cardiac sympathetic activation is associated with adverse outcome in patients with chronic heart failure (CHF), the influence of renal sympathetic activity on outcome is unknown. We assessed the hypothesis that renal noradrenaline (NA) spillover is a predictor of the combined endpoint of all-cause mortality and heart transplantation in CHF. METHODS AND RESULTS: Sixty-one patients with CHF, New York Heart Association (NYHA) I-IV (66% NYHA III-IV), and left ventricular ejection fraction (LVEF) 26+/-9% (mean+/-SD) were studied with cardiac and renal catheterizations at baseline and followed for 5.5+/-3.7 years (median 5.5 years, range 12 days to 11.6 years). Nineteen deaths and 13 cases of heart transplantation were registered. Only renal NA spillover above median, 1.19 (interquartile range 0.77-1.43) nmol/min, was independently associated with an increased relative risk (RR) of the combined endpoint (RR 3.1, 95% CI 1.2-7.6, P=0.01) in a model also including total body NA spillover, LVEF, glomerular filtration rate (GFR), renal blood flow, cardiac index, aetiology, and age. CONCLUSION: Renal noradrenergic activation has a strong negative predictive value on outcome independent of overall sympathetic activity, GFR, and LVEF. These findings suggest that treatment regimens that further reduce renal noradrenergic stimulation could be advantageous by improving survival in patients with CHF. 相似文献
29.
Prognostic information from cytogenetic analysis in chronic B-lymphocytic leukemia and leukemic immunocytoma 总被引:2,自引:1,他引:2
G Juliusson K H Robèrt A Ost K Friberg P Biberfeld B Nilsson L Zech G Gahrton 《Blood》1985,65(1):134-141
Fifty-five patients with a clonal expansion of B lymphocytes in the peripheral blood were studied. According to the Kiel classification, 22 patients had chronic lymphocytic leukemia (CLL), 29 had immunocytoma (IC), two had prolymphocytic leukemia, and one had centrocytic lymphoma; one was not subclassified. Cytogenetic studies after B cell mitogen stimulation showed that six patients had an extra chromosome 12 as the sole abnormality. Another ten patients had an extra chromosome 12 together with other abnormalities. One patient had dup(12). Fifteen patients showed clonal aberrations without +12. Eleven patients showed only normal metaphases, and 12 patients were not evaluated cytogenetically. The cytogenetic subgroup pattern did not distinguish between CLL and IC patients. There was no significant difference between the CLL and IC groups as regards clinical findings and prognosis. However, the cytogenetic typing proved to be of prognostic significance. Increasing numbers of chromosomal aberrations within the cell clone were significantly associated with a poorer prognosis, ie, with impairment of survival (P = .04) and therapy-free survival (P less than 10(-4]. Patients with complex karyotypes (at least clonal aberrations) showed the poorest survival (P = .007). Patients with +12 required treatment earlier than patients with a normal karyotype (P = .01) and patients with karyotypic changes other than +12 (P = .006). These latter differences were even more pronounced when only IC patients were considered (P = .005 and P = .002, respectively). A multivariate analysis revealed that +12 was as strong an indicator of poor survival as advanced Rai or Binet stages and a stronger predictor of therapy-demanding disease. 相似文献
30.
Ahmed A. Harhash Teresa L. May Chiu-Hsieh Hsu Sachin Agarwal David B. Seder Michael R. Mooney Nainesh Patel John McPherson Paul McMullan Richard Riker Eldar Soreide Karen G. Hirsch Pascal Stammet Alison Dupont Sten Rubertsson Hans Friberg Niklas Nielsen Tanveer Rab Karl B. Kern 《Journal of the American College of Cardiology》2021,77(4):360-371
BackgroundThe American College of Cardiology Interventional Council published consensus-based recommendations to help identify resuscitated cardiac arrest patients with unfavorable clinical features in whom invasive procedures are unlikely to improve survival.ObjectivesThis study sought to identify how many unfavorable features are required before prognosis is significantly worsened and which features are most impactful in predicting prognosis.MethodsUsing the INTCAR (International Cardiac Arrest Registry), the impact of each proposed “unfavorable feature” on survival to hospital discharge was individually analyzed. Logistic regression was performed to assess the association of such unfavorable features with poor outcomes.ResultsSeven unfavorable features (of 10 total) were captured in 2,508 patients successfully resuscitated after cardiac arrest (ongoing cardiopulmonary resuscitation and noncardiac etiology were exclusion criteria in our registry). Chronic kidney disease was used in lieu of end-stage renal disease. In total, 39% survived to hospital discharge. The odds ratio (OR) of survival to hospital discharge for each unfavorable feature was as follows: age >85 years OR: 0.30 (95% CI: 0.15 to 0.61), time-to-ROSC >30 min OR: 0.30 (95% CI: 0.23 to 0.39), nonshockable rhythm OR: 0.39 (95% CI: 0.29 to 0.54), no bystander cardiopulmonary resuscitation OR: 0.49 (95% CI: 0.38 to 0.64), lactate >7 mmol/l OR: 0.50 (95% CI: 0.40 to 0.63), unwitnessed arrest OR: 0.58 (95% CI: 0.44 to 0.78), pH <7.2 OR: 0.78 (95% CI: 0.63 to 0.98), and chronic kidney disease OR: 0.96 (95% CI: 0.70 to 1.33). The presence of any 3 or more unfavorable features predicted <40% survival. Presence of the 3 strongest risk factors (age >85 years, time-to-ROSC >30 min, and non-ventricular tachycardia/ventricular fibrillation) together or ≥6 unfavorable features predicted a ≤10% chance of survival to discharge.ConclusionsPatients successfully resuscitated from cardiac arrest with 6 or more unfavorable features have a poor long-term prognosis. Delaying or even forgoing invasive procedures in such patients is reasonable. 相似文献