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21.
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration.  相似文献   
22.
Object A radiation dose of 40–50 Gy is able to produce a cure rate of more than 90% in intracranial pure germinoma. However, many attempts have been made to reduce the dose and volume of radiation without compromising the disease control rate because of the toxicity of irradiation. This retrospective study is intended to provide the physician with an appropriate therapeutic strategy. Materials and methods We reviewed a series of 10 recurrent germinomas among 117 germinomas diagnosed histologically or clinically between 1979 and 2002. These patients involved underwent three different treatment modalities; radiation alone (N = 71), chemotherapy alone (N = 9), and combined therapy (N = 37). The 10-year overall and relapse-free survival rates were 97 and 93% in the radiation alone group, 89 and 67% in the chemotherapy alone group, and 92 and 92% in the combined therapy group, respectively. As expected, both radiation therapy and combined therapy were effective in controlling the disease. Tumor recurrence was closely related to the volume of radiation but not to the dose of radiation. If the tumor bed and craniospinal axis were fully covered, the radiation dose might be reduced. Chemotherapy alone showed earlier recurrence and a higher tumor recurrence rate. In the case of combined therapy, chemotherapy was useful in reducing the radiation dose but revealed some toxicity (death of two patients). Conclusions The investigation of a possible further dose reduction seems worthwhile. Radiation therapy alone with a dose of less than 40 Gy should be compared with ongoing chemotherapeutic protocols combined with low-dose irradiation.  相似文献   
23.
The original article to which this Erratum refers was published in Pharmacoepidemiology and Drug Safety 2005; 14: 239–247.  相似文献   
24.
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition.  相似文献   
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26.
The pharmacokinetics of midazolam and its metabolites were studied in 17 patients on mechanical ventilation in a general intensive care unit who were receiving a continuous intravenous infusion of midazolam, adjusted according to the level of induced sedation. Three patients were studied twice. Serum midazolam and alpha-hydroxymidazolamglucuronide levels were determined during and after infusion. The sedation level was scored on a four-point scale. Half of the observed patients were still drowsy or asleep 10 hours after termination of midazolam infusion. In only one patient was midazolam serum elimination half-life less than 2 hours and in six patients the half-life was greater than 10 hours. A wide range of midazolam serum levels was associated with adequate sedation, and similarly the midazolam levels at the moment of awakening were highly variable. The serum concentration ratio of midazolam/alpha-hydroxymidazolamglucuronide at the end of the infusion varied from 0.03 to 15.6. Renal function could account for only a part of this variation.  相似文献   
27.
This paper describes the isolation of isoguanosine from Croton tiglium L. and its cytotoxic effect against several tumor cell lines in culture and newly reports that isoguanosine has an antitumor activity against implanted S-180 ascitic tumor mice. Isoguanosine is effective at the dose of 24 mg/kg/day x 5, with T/C value of 168%. Isoguanosine inhibits the growth of S-180 and Ehrlich solid tumor in mice at the optimal doses of 96 mg/kg/day x 12 and 48 mg/kg/day x 12, with 1-T/C values of 65% and 60%, respectively.  相似文献   
28.
29.
POEMS syndrome is a multisystem disorder associated with plasmacell dyscrasias. This report describes a patient with POEMS-associatedrenal disease and reviews the literature on biopsy-proven renalinvolvement in POEMS syndrome. Our patient had glomerulonephritiswith membranoproliferative features on light-microscopy withoutcharacteristic findings on immunofluorescence, and with ultra-structural evidence of glomerular microangiopathy. Ultrastructuralevidence of microangiopathy was also found in vasa nervorum.In 20 other cases of POEMS- associated renal disease, 16 hadglomerular disease. Light-microscopy showed membranoproliferative-likeglomerulopathy in 14 patients and glomerular microan giopathyin two. Ultrastructural evidence of microangi opathy was presentin all 15 patients in whom electron- microscopy was done. Thus,in most patients with POEMS-associated glomerular disease acharacteristic lesion is present with evidence of endothelialinjury. As endothelial damage is also found in endoneural vessels,generalized endothelial injury may play a role in non-renalmanifestations of POEMS syndrome. In previous reviews manifestationsof the POEMS syndrome were similar for patients with or withoutmyeloma. Among patients with biopsy-proven glomerular disease,however, myeloma patients are underrepres ented. Whether thisrepresents a sampling error or has true pathophysiological significanceremains to be established.  相似文献   
30.
Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation assay and these results suggest that it might be a immunosuppressant.  相似文献   
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