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21.
22.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
23.
Important risk factors of allograft survival in cadaveric renal transplantation. A study of 426 patients. 总被引:1,自引:1,他引:0
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A G Diethelm E H Blackstone D C Naftel S L Hudson W H Barber M H Deierhoi B O Barger J J Curtis R G Luke 《Annals of surgery》1988,207(5):538-548
Multiple risk factors contribute to the allograft survival of patients who have cadaveric renal transplantation. A retrospective review of 19 such factors in 426 patients identified race, DR match, B + DR match, number of transplants, and preservation time to have a significant influence. The parametric analysis confirmed the effect to be primarily in the early phase, i.e., first 6 months. All patients received cyclosporine with other methods of immunosuppression resulting in an overall 1-year graft survival rate of 66%. The overall 1-year graft survival rate in the white race was 73% and in the black race was 57% (p = 0.002). Allograft survival and DR match showed white recipients with a 1 DR match to have 75% survival at 1 year compared with 57% in the black patient (p = 0.009). If HLA B + DR match was considered, the white recipient allograft survival increased to 76%, 84%, and 88% for 1, 2, and 3 match kidneys by parametric analysis. Patients receiving first grafts had better graft survival (68%) than those undergoing retransplantation (58%) (p = 0.05). Organ preservation less than 12 hours influenced allograft survival with a 78% 1-year survival rate compared with 63% for kidneys with 12-18 hours of preservation. Despite the benefits of B + DR typing, short preservation time, and first transplants to the white recipient, the allograft survival in the black recipient remained uninfluenced by these parameters. 相似文献
24.
25.
P Barber 《The European respiratory journal》2004,24(4):710-1; author reply 711
26.
Benefits of quadruple immunosuppressive therapy in recipients of living related donor kidneys. A review of 855 operations.
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A G Diethelm D A Laskow S L Hudson M H Deierhoi W H Barber B O Barger B A Julian R S Gaston J J Curtis 《Annals of surgery》1992,215(6):606-617
Eight hundred fifty-five living related donor transplant recipients were analyzed according to 15 potential risk factors with regard to patient and graft survival according to immunosuppression. Group I, 1968 to 1983, (n = 440 patients) received azathioprine and prednisone; group II, 1984 to 1987, (n = 229 patients) received triple therapy--azathioprine, prednisone, and cyclosporine; and group III, 1988-1991, (n = 186 patients), quadruple therapy--azathioprine, prednisone, cyclosporine, and Minnesota antilymphocyte globulin. Three important risk factors included immunosuppression, tissue typing, and race. Groups II and III had improved allograft survival over group I (p = 0.03). Patients with two haplotype matches had similar survival in all three groups. Kidney survival in one-haplotype-matched recipients improved in group II and was equal to that of the two-haplotype-matched patients in group III. Cyclosporine improved allograft survival in both races when combined with azathioprine and prednisone. Quadruple therapy improved early survival in one-haplotype black patients, even though long-term results remained better in whites. Cyclosporine did not improve graft survival in two-haplotype recipients. The addition of cyclosporine and quadruple therapy did not increase morbidity and mortality rates. 相似文献
27.
Dendritic development and preferential growth into synaptogenic fields: a quantitative study of Golgi-impregnated spinal motor neurons 总被引:1,自引:0,他引:1
Branching patterns of dendrites may be modulated by the way in which dendritic growth cone filopodia come into initial synaptic relationships with afferent axons. This synaptotropic hypothesis of dendritic branching predicts that dendritic growth will be directed preferentially into regions containing numerous prospective presynaptic elements. The developing mouse spinal cord provides a natural experiment to test this prediction, because synapses are found exclusively within the marginal zones bordering the motor columns during the early (E11-14) period of synaptogenesis. During this time, therefore, most motor dendritic growth would be expected to be directed laterally or ventrally into the marginal zones, whereas internally directed growth should become more prevalent later, when synaptogenesis begins to take place within the intermediate zone, i.e., the motor columns proper. A computer-assisted three dimensional reconstruction system has been used to test these expectations in Golgi preparations of developing mouse (C57BL/6J) spinal cords ranging in age from E13 through P1. Mean dendritic lengths and branch densities are significantly greater for marginal zone dendrites than for intermediate zone dendrites at early ages (E13-14), but there are no significant differences in these measures at later stages of development (P0,1). These findings are interpreted as meaning that motor dendritic growth is initially biased into the marginal zone by synaptogenic afferents and that this preferential distribution is progressively lost as synapses develop within the intermediate zone to attract or to stabilize internally directed dendritic growth. Thus the findings of this study are consistent with predictions of the synaptotropic hypothesis of dendritic branching. 相似文献
28.
29.
本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。 相似文献
30.
Eugene D. Barber 《Environmental and molecular mutagenesis》1994,23(3):228-233
Di(2-ethylhexyl) terephthalate (DEHT) is a commercially produced chemical (Kodaflex® DOTP) that is used as a general purpose, low-volatility plasticizer for polyvinyl chloride and other polymeric materials. Less than 30 million kilograms of DEHT are produced annually. DEHT is isomeric with di(2-ethylhexyl) phthalate (DEHP), a nongenotoxic rodent carcinogen whose mode of action has been suggested to derive from its ability to produce hepatocellular proliferation and/or hepatic peroxisome proliferation. Thus it is important to know the behavior of DEHT in genotoxicity assays in order to compare it with that of DEHP and other phthalate ester plasticizers. It is known from previously published studies that rats fed DEHT in the diet at 2,000 mg/kg produce urine that is negative in the Ames Salmonella bacterial mutagenicity assay in the presence and absence of induced rat liver S-9 and in the presence and obsence of β-glucuronidase/aryl sulfatase. Reported here are the results of direct testing of DEHT in the Ames plate incorporation assay, the Chinese hamster ovary/hypoxanthine guanine phosphoribosyl transferase (CHO/HGPRT) in vitro mammalian cell mutagenicity assay, and an in vitro chromosome aberrations assay using CHO cells. The results for mono(ethylhexyl) terephthalate (MEHT), a metabolite of DEHT, in the Ames Salmonella bacterial mutagenicity assay are also presented. All test results for both DEHT and MEHT were found to be negative, and it is therefore concluded that DEHT, like its isomeric relative DEHP, is not genotoxic. © 1994 Wiley-Liss, Inc. 相似文献