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1.
Serum rheumatoid factors (RF) were measured yearly in 135 women with rheumatoid arthritis by the Waaler-Rose and latex fixation tests and IgM, IgA, and IgG RF were measured by enzyme linked immunosorbent assays (ELISAs). The patients were followed up from an early phase of the disease for a mean duration of six years. Patients with a persistently positive RF test, irrespective of the type of test used, had more radiological abnormalities, more disease activity, worse functional ability, more extra-articular manifestations, and needed more treatment with second line drugs than patients with persistently negative or variably positive and negative test results during the follow up. Increased RF levels, especially a high level of IgA RF within three years of the onset of symptoms, was prognostic for a more severe disease outcome six years after the onset of symptoms.  相似文献   
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As several reinjection procedures have shown encouraging results in terms of imaging, we investigated whether the kinetics of thallium-201 would differ between the standard stress-redistribution-reinjection approach and the stress-immediate reinjection approach. In 53 consecutive patients with undiagnosed chest pain, 75 MBq (2 mCi)201Tl was injected at maximal exercise. In 26 of these patients (group I), 37 MBq (1 mCi)201Tl was reinjected immediately after completing the exercise images (the immediate reinjection procedure) and in 27 patients (group II), 37 MBq (1 mCi)201Tl was reinjected after completing 3-h redistribution images (the standard reinjection procedure). Mean peak201Tl blood activity after exercise was 17.7±12.5 kBq/ml (4.8±3.4 mCi/ml) for group I versus 16.4±9.2 kBq/ml (4.4±2.5 mCi/ml) for group II (NS). The relative increase in201Tl blood activity after reinjection of half the initial dose [37 MBq (1 mCi)] exceeded 50% of the initial peak in both groups. The relative amount of201Tl delivered to the myocardium was assessed by the area under the curve after both exercise and reinjection, and was 117%±72% for group I and 112%±73% for group II (NS). Blood clearance of201Tl was at least biexponential. Mean early decay constants (1) after exercise and reinjection were 0.30±0.18 min–1 and 0.22±0.046 min–1 respectively for group I (T 1/2 2.3 min and 3.2 min respectively, NS), and 0.30±0.12 min–1 and 0.24±0.07 min–1 respectively for group II (T 1/2 2.3 min and 2.9 min respectively, NS). For both procedures no significant differences were found between 1 after exercise and 1 after injection. The mean late clearance (2) from the blood was 0.032±0.056 min–1 and 0.012±0.012 min–1 respectively for group I (T 1/2 21.6 min and 57.7 min respectively, NS), and 0.036±0.030 min–1 and 0.014±0.014 min–1 respectively for group II (T 1/2 19.3 min and 49.5 min respectively, NS). Also, no significant differences were found between 2 after exercise for both groups and between 2 after reinjection for both groups. We conclude that reinjection of 37 MBq (1 mCi)201Tl (half the initial dose) results in a relative increase in the initial peak and a relative increase in the amount of201Tl delivered to the myocardium of more than 50% for both the standard and the immediate reinjection procedure. The clearance of201Tl from the blood was not influenced by exercise or by the time of reinjection. Based on201Tl kinetics as measured in the peripheral blood, there is no reason to postpone reinjection until 3–4 h following exercise.  相似文献   
3.
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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In renal transplantation, use of calcineurin inhibitors (CNIs) is associated with nephrotoxicity and immunosuppression with malignancies and infections. This trial aimed to minimize CNI exposure and total immunosuppression while maintaining efficacy. We performed a randomized controlled, open‐label multicenter trial with early cyclosporine A (CsA) elimination. Patients started with basiliximab, prednisolone (P), mycophenolate sodium (MPS), and CsA. At 6 months, immunosuppression was tapered to P/CsA, P/MPS, or P/everolimus (EVL). Primary outcomes were renal fibrosis and inflammation. Secondary outcomes were estimated glomerular filtration rate (eGFR) and incidence of rejection at 24 months. The P/MPS arm was prematurely halted. The trial continued with P/CsA (N = 89) and P/EVL (N = 96). Interstitial fibrosis and inflammation were significantly decreased and the eGFR was significantly higher in the P/EVL arm. Cumulative rejection rates were 13% (P/EVL) and 19% (P/CsA), (p = 0.08). A post hoc analysis of HLA and donor‐specific antibodies at 1 year after transplantation revealed no differences. An individualized immunosuppressive strategy of early CNI elimination to dual therapy with everolimus was associated with decreased allograft fibrosis, preserved allograft function, and good efficacy, but also with more serious adverse events and discontinuation. This can be a valuable alternative regimen in patients suffering from CNI toxicity.  相似文献   
7.
Metabolic adaptation of the chick embryo to chronic hypoxia   总被引:1,自引:0,他引:1  
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AIMS: Nowadays, most women born with aortic coarctation reach childbearing age. However, data on outcome of pregnancy in women after repair of aortic coarctation are scarce. The aim of this study was to report on maternal and neonatal outcome of pregnancy in women after aortic coarctation repair. METHODS AND RESULTS: The CONCOR national registry on congenital heart disease in The Netherlands was reviewed for women of childbearing age (> or =18 years old) with a history of aortic coarctation repair. Medical history and maternal, obstetrical, and neonatal outcome were determined. Fifty-four of the 100 women included had a history of pregnancy. The 54 women had 126 pregnancies resulting in 98 successful pregnancies, 22 miscarriages, and six abortions. The success rate was estimated as 0.778 (SE 0.002) including abortions and 0.817 (SE 0.002) excluding abortions. There were 85 vaginal deliveries, seven vaginal deliveries with epidural analgesia, and six caesarean sections. There were two neonatal deaths. A total of 26 pregnancies were complicated by a hypertensive disorder of pregnancy. There were 21 pregnancies in 14 women complicated by hypertension and five pregnancies in four women complicated by pre-eclampsia. The hypertension- and pre-eclampsia-probabilities were estimated as 0.183 (SE 0.285) and 0.061 (SE 0.211), respectively. During pregnancy, five patients had an increase > or =15 mmHg across the site of repair at echocardiography, but only one patient required reintervention for recoarctation after delivery. Four of the 98 children (4%) had a congenital heart defect. CONCLUSION: Pregnancy is well tolerated in women after repair of aortic coarctation. However, an excess of miscarriages and hypertensive disorders of pregnancy were found.  相似文献   
10.
背景目前已开展了对重性精神病患者进提供连续性服务的研究。目的探讨基层对有抑郁症风险患者提供连续性服务的水平,并与对心力衰竭患者的服务水平进行对比。方法采用抑郁症风险患者与心力衰竭患者对比的探索性研究。采用患者问卷评估服务的持续性,包含如下内容:(1)联系的服务提供者数(个人连续性);(2)诊所内服务提供者之间的合作(团队连续性)(6个项目,分数1~5分);(3)诊所外全科医师与服务提供者之间的合作(跨界连续性)(4个项目,分数1~5分)。结果大多数抑郁症风险患者在过去1年中寻遍整个服务提供界联系了几个服务提供者,曾遇到过高水平团队连续性服务及低水平跨界连续性服务。在诊所中可接触到的不同服务提供者要明显多于心力衰竭患者服务提供者(P<0.01)。抑郁症风险患者的服务提供者之间的合作更好一些,每项平均得分4.3分,心力衰竭患者得分为4.0分(P=0.03)。然而,跨界连续性服务方面正好相反:抑郁症风险患者每项平均得分3.5分,心力衰竭患者得分为4.0分(P=0.01)。结论抑郁症风险患者与心力衰竭患者之间的探索性对比显示:体验服务连续性方面的差距不大。对此还应行进一步分析。  相似文献   
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