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61.
BACKGROUND: Sodium removal (NaR) may have a major impact on the survival of peritoneal dialysis patients. The dialysate/plasma sodium concentration ratio (D/P(Na)) is an indirect index of transcellular water transport by aquaporin channels, and thus of ultrafiltration. Sodium concentration can be assessed by means of flame photometry (F), and direct (D-ISE) or indirect ion-selective electrodes (I-ISE), but these methods have different properties. I-ISE is being used increasingly in clinical laboratories. The aim of this study was to evaluate NaR and D/P(Na) using the three different measurement methods. METHODS: We performed peritoneal equilibration tests (PETs) in 44 peritoneal dialysis patients and calculated the NaR. We also calculated D/P(Na) during the test; plasma and dialysate sodium concentrations were measured by F, D-ISE and I-ISE. RESULTS: NaR was lower (P<0.001) with D-ISE (69+/-29 mmol) than with F (81+/-29 mmol) or I-ISE (79+/-28 mmol). D/P(Na) was also lower at baseline (0.92+/-0.02 vs 0.95+/-0.02 and 0.95+/-0.02; P<0.001), after 60 min (0.87+/-0.03 vs 0.90+/-0.03 and 0.90+/-0.03; P<0.001) and at the end of PET (0.88+/-0.04 vs 0.92+/-0.04 and 0.92+/-0.04; P<0.001) when measured by D-ISE in comparison with F and I-ISE, respectively. CONCLUSIONS: NaR and D/P(Na) were lower when measured by the D-ISE method compared with the F and I-ISE methods. NaR and D/P(Na) were similar when measured by F or I-ISE. I-ISE can be used reliably in the evaluation of NaR and D/P(Na) in everyday clinical practice of peritoneal dialysis.  相似文献   
62.
63.
A series of 1153 fine-needle aspiration biopsies (FNAB) of breast masses obtained during the period 1985 to 1988 in one institution was examined. The following diagnostic accuracy values were found: sensitivity, 93.0%; specificity, 92.4%; predictive positive value, 93.7%; and efficiency, 92.8%. These results were compared with a previously published series for the period 1976 to 1984. The diagnostic accuracy values did not differ significantly between the two series.  相似文献   
64.
股骨头缺血坏死的低场MRI评价   总被引:9,自引:1,他引:8  
目的: 分析股骨头缺血坏死(ANFH)低场MRI征象,评价ANFH的MRI分期及其关节积液的分级.材料和方法:在分析50例正常髋MRI基础上回顾性对照分析51例(90个股骨头)ANFH的低场MRI和X线平片资料.结果:90个ANFH中,20个(22 %) X线平片为阴性;64个(71%)MRI示"脂肪强度征"即坏死区内或近侧可见类似皮下脂肪样信号.按照 Hungerford分期:0期9个,Ⅰ期13个,Ⅱ期31个,Ⅲ期26个,Ⅳ期11个.ANFH引起的关节积液多为2~3级(60个髋,占67%);Ⅲ、Ⅳ期ANFH合并关节积液量比0~Ⅱ期明显多(P<0.005).结论:低场MRI能够准确显示ANFH的范围、程度、信号特征及其关节积液的情况,并能够对早期ANFH作出可靠诊断;"脂肪强度征"为低场MRI的特征性表现,对诊断ANFH有非常重要的价值.  相似文献   
65.
Repetitive conservative surgery for recurrence of endometriosis   总被引:4,自引:0,他引:4  
We evaluated the recovery of fertility and the relief of pain symptoms in a long-term follow-up of 42 women undergoing repetitive conservative surgery for recurrent endometriosis. The mean age of the patients was 31.1 +/- 4.3 years. At the time of their second operation the disease was stage IV in 14 women, stage III in 25, and stage I in three. After reoperation, the patients were followed for a mean period of 41.8 +/- 30.3 months. Pain symptoms returned in eight women, dysmenorrhea and deep dyspareunia in eight, and pelvic pain in seven. Eight of the 28 women (28.6%) who attempted to conceive achieved a total of 13 pregnancies. The corrected pregnancy rate was 35%, and the cumulative rate at 27 months was 30.7%. A third operation was necessary in six women after a mean period of 35 months. Conservative surgery is an effective therapeutic option for infertile patients with recurrent endometriosis.  相似文献   
66.
Central sensory and motor conduction in vitamin B12 deficiency.   总被引:7,自引:0,他引:7  
Four patients with subacute combined degeneration were studied through upper and lower limb SEPs recorded with a non-cephalic reference montage and through cortical and spinal magnetic stimulation. Clinical signs were confined to the lower limbs in 3 patients; the remaining patient presented only paraesthesiae in 4 limbs. Median nerve SEPs showed a normal cervical N13 response with a significant increase of central conduction time concerning exclusively the P9-P14 interpeak interval. Central motor conduction to upper and lower limb muscles was abnormal. Nerve conduction studies provided no evidence of peripheral nerve involvement. These electrophysiological findings suggest that in vitamin B12 deficiency the higher segments of the cervical cord are usually affected first and that central sensory and motor conduction studies are sensitive methods for detecting such damage.  相似文献   
67.
白细胞介素—2新的功能位点及其中枢镇痛作用   总被引:2,自引:0,他引:2  
白细胞介素-2(IL-2)不仅是重要的免疫调节因子,而且还具有重要的中枢调节作用。本实验以钾离子透入引起大鼠甩尾反应为指标,发现侧脑室注射IL—2能显著提高动物痛阈,并能被纳洛酮所阻断,表示IL-2的中枢镇痛作用可能与阿片受体有关。利用基因定位突变技术获得的无免疫活性IL-2实查体仍具有中枢镇痛作用,表明IL—2分子上发挥镇痛和免疫调节作用的功能位点是相互独立的。纳洛酮能够阻断IL—2的中枢镇痛作用,而不能影响IL—2增殖CTLL-2细胞的作用,提示IL-2发挥镇痛和免疫调节作用可能通过不同的受体途径。IL-2分子中第45位Tyr残基突变为Val后,虽仍保留了免疫活性,但丧失了镇痛功能,表示45位Tyr残基是IL—2发挥中枢镇痛功能的关键残基之一。我们推测IL—2的镇痛功能位点可能在IL—2分子中第45位Tyr残基附近区域。  相似文献   
68.
The Marlowe-Crowne Social Desirability Scale, a 33-item self-report questionnaire, was administered to an age-matched sample of twenty-five irritable bowel syndrome (IBS) patients, twenty-four psychiatric patients meeting a diagnosis of major depression, and nineteen controls. As predicted, planned comparisons analysis showed a significant group effect: IBS group scores were significantly higher than both depressed and control group scores (p less than .05). Implications of this social desirability response set for the psychological assessment and treatment of IBS are discussed.  相似文献   
69.
We studied the histories of patients who had visited our Department during the last 5 years, presenting food allergy with exclusively respiratory symptoms (18.5%). We studied the correlation between IgE levels and the histamine release test and the type of food implicated. Seventy-seven percent of patients presented sensitization to one food, and 23% presented polysensitization. We found that foods such as snails and eggs have a strong predilection for the bronchial tree as the shock organ. High total IgE was found in 85.2% of patients. The histamine release test was positive in 66% of cases. We conclude that this is a highly sensitive method for the in vitro diagnosis of food allergy.  相似文献   
70.
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