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3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG CoA) reductase inhibitors are widely used to decrease plasma cholesterol levels in patients with heterozygous familial hypercholesterolemia (FH) who are at increased risk of premature coronary artery disease. Tissue-culture and animal studies have indicated that administration of HMG CoA reductase inhibitors (eg, lovastatin, simvastatin, etc) induces a compensatory increase in the activity of HMG CoA reductase, both by increasing its synthesis and decreasing catabolism. To determine in human subjects whether cessation of therapy with this class of drugs leads to induction of HMG CoA reductase activity and above-normal rates of cholesterol biosynthesis, we measured urinary concentrations of mevalonic acid (an indicator of cholesterol biosynthesis) after the cessation of therapy with lovastatin and simvastatin (80 mg/day) in patients with heterozygous FH. Plasma concentrations of LDL increased promptly on discontinuation of reductase inhibitor therapy but did not increase above pretreatment levels at any point after drug discontinuation. Similarly, the 24-hour urinary excretion of mevalonic acid was reduced during treatment with lovastatin or simvastatin and increased promptly on discontinuation of drug but did not increase to levels exceeding those found at baseline when the patients were receiving dietary therapy only. We conclude that cessation of treatment with HMG CoA reductase inhibitors in patients with FH does not result in a rebound increase in cholesterol biosynthesis and that no rebound overshoot occurs in plasma concentrations of low-density-lipoprotein cholesterol.  相似文献   
86.
Liver transplantation is a new treatment for familial amyloidotic polyneuropathy (FAP). No qualitative study examining these patients' experiences of the disease and the treatment has been published. The purpose of this study was to explore and describe the experience of the disease and the liver transplantation from the FAP patient's perspective. In-depth interviews with 11 liver transplant FAP patients were performed. The process of the FAP disease and a liver transplantation was found to involve the following categories: going downhill, defence and denial, a chance of surviving, the decision — no choice, waiting powerless and uncertain, the first few steps after surgery, freed from the death sentence, still disabled, mastering up strength to recover, and the need for support and help.  相似文献   
87.
目的:低白蛋白血症是肝移植患者的常见并发症,也是患者预后的重要影响因素。肝移植术后选择合理的白蛋白应用方案将有益于提高肝移植患者术后近远期疗效。方法:选择2000-10/2005-06于北京大学第三医院行肝移植并且随访时间大于6个月的患者80例,对治疗方案均知情同意。医院自2003年8月开始改变了肝移植术后白蛋白的输入方案:①方案改变之前患者即白蛋白输入方案未改变组(n=50),术后早期常规输入白蛋白剂量大于60g/d。②方案改变之后患者即白蛋白输入方案改变组(n=30),适当减少术后早期白蛋白输入的常规剂量至0 ̄20g/d。统计分析两组患者的一般情况、术后白蛋白使用情况、预后情况及住院费用。另外,对于两组中术后存在低白蛋白相关严重并发症的患者进行进一步的比较分析。结果:80例患者全部进入结果分析。①两组患者术前及术中一般情况差异无显著性意义(P>0.05)。②白蛋白输入方案改变组术后早期白蛋白的使用量及其费用/总住院费用比例显著低于白蛋白输入方案未改变组(P<0.01)。但两组患者术后第3天肝功能情况、白蛋白水平、早期并发症发生率、早期死亡率、半年生存率及呼吸机时间等情况差异均无显著性意义(P>0.05)。③两组中术后出现低白蛋白相关严重并发症患者术后第3天肝功能情况、白蛋白水平、早期死亡率、半年生存率及呼吸机应用时间等情况差异均无显著性意义(P>0.05)。结论:肝移植术后过多输入白蛋白不能改善患者预后;适当减少术后白蛋白的常规输入剂量,同时根据血白蛋白水平及并发症情况随时调整白蛋白的输入量能够减少白蛋白的用量,对患者预后因素亦无明显影响。  相似文献   
88.
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic pulmonary infection/inflammation which leads to respiratory failure. The presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has previously been observed in the sera of patients with CF. In view of the known relationship of ANCA with primary vasculitis and of their putative pathogenetic role in these disorders, we studied the presence, specificity and isotype of ANCA and their clinical associations in 66 adult CF patients. None of the 66 CF samples had autoantibodies to the major ANCA antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples contained IgG and 55/66 (83%) IgA, autoantibodies to bactericidal/permeability increasing protein (BPI), a recently characterized ANCA specificity. All the IgA anti-BPI-positive samples were also IgG anti-BPI-positive. The autoantibody specificity was confirmed by inhibition assay and immunoblotting of CF sera against a neutrophil granule preparation. Furthermore, in this cross-sectional study, anti-BPI levels were inversely correlated with the observed reductions in FEV1 and FVC (IgA anti-BPI and FEV1: r = 0.508, <it>p</it> &lt; 0.0001), and both IgG and IgA anti-BPI levels were higher in CF patients with secondary vasculitis (<it>n</it> = 6) than in those without (<it>p</it> &lt; 0.05). ANCA with specificity for BPI were present in the majority of CF sera in this study and autoimmune processes may be associated with the development of pulmonary injury in CF.   相似文献   
89.
Felty's syndrome (FS) (rheumatoid arthritis with neutropenia and splenomegaly) has a poor prognosis, largely because of the high risk of severe infection. Granulocyte colony-stimulating factor (G-CSF) is an emerging treatment for chronic neutropenia. We prospectively monitored its use in eight patients with recurrent infections or who required joint surgery. Significant side-effects were documented in five, including nausea, malaise, generalized joint pains, and in one patient, a vasculitic skin rash. In two patients treatment had to be stopped, and in these cases G-CSF had been started at full vial dosage (300 micrograms/ml filgrastim or 263 micrograms/ml lenograstim) alternate days or daily. G-CSF treatment was continued in three patients by restarting at reduced dose, and changing the proprietary formulation. G- CSF raised the neutrophil count, reduced severe infection, and allowed surgery to be performed. A combined clinical and laboratory index suggested that long-term treatment (up to 3.5 years) did not exacerbate the arthritis. Once on established treatment, it may be possible to use smaller weekly doses of G-CSF to maintain the same clinical benefit. One of the three patients whose FS was associated with a large granular T-cell lymphocytosis showed a reduction in this subset of lymphocytes during G-CSF treatment.   相似文献   
90.
Growth factors have been identified as the primary cause of osteoinduction in bone healing. Transforming growth factor beta (TGF- beta) has been shown to promote bone formation and is present in bone in high quantities. The aims of the present study were to isolate TGF- beta from human bone, demonstrate its biologic activity, and analyze the effects of conventional sterilization techniques on activity. Bone, obtained from femoral heads of five patients (mean age, 70 years) was ground, demineralized, and freeze-dried, and samples from each patient were divided into three groups: no treatment, sterilization with 1.60 to 1.94 Mrad of 60Co irradiation, and sterilization with ethylene oxide (ETO). Carrier-free recombinant TGF-beta control was also treated and was totally inactivated by ETO but not by irradiation (p < 0.01). TGF- beta activity in demineralized bone was not significantly diminished (p > 0.1) by either sterilization procedure, and substantial amounts of active TGF-beta were recovered in all bone samples: 1.04 +/− 0.77 ng per mg of protein in irradiated samples, 0.67 +/− 0.26 ng per mg in ETO- treated samples, and 1.04 +/− 0.33 in untreated samples, respectively (mean +/− SD). Although a recent report demonstrated that the osteoinductive activity of bone morphogenetic protein in bone powder is diminished considerably by ETO and by 2.5 Mrad of irradiation sterilization of bone powder, these data demonstrate that TGF-beta activity, with its osteoinductive properties, was not destroyed in more coarsely ground, demineralized bone by ETO or by lower doses of irradiation. These findings support the use of human bone allografts in clinical instances involving impaired bone formation.  相似文献   
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