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991.
A woman who had been taking amiodarone--400 mg/day--for over nine years, developed cirrhosis. Electron microscopy showed phospholipid-laden lysosomal lamellar bodies containing myelin figures. A review is made about the reported cases of amiodarone-induced cirrhosis, including detailed histological findings. We conclude that periodical clinical and biochemical monitoring must be made in patients receiving treatment with amiodarone, and that the pathophysiologic mechanism responsible for the amiodarone toxicity still remains unclear.  相似文献   
992.
The pharmacokinetics and toxicity of intravenous lonidamine were investigated in dogs receiving four cycles of lonidamine (400 or 800 mg/m2) +/- whole-body hyperthermia (WBH). Clearance and volume of distribution in dogs receiving lonidamine during WBH increased 1.6-2.3 and 1.9-3.5-fold respectively, relative to dogs receiving lonidamine under euthermic conditions (p < 0.02). In dogs receiving lonidamine under euthermic conditions or 400 mg/m2 + WBH, the area under the lonidamine concentration versus time curve (AUC) measured during the fourth treatment was 21-58% lower than the first treatment AUC. However, in dogs receiving 800 mg/m2 + WBH, the fourth treatment AUC was four-fold higher than the first treatment AUC (p < 0.02). This suggests repeated exposure to 800 mg/m2 lonidamine and WBH impairs lonidamine metabolism. Weakness, hypoglycaemia, and elevations in amylase, alanine aminotransferase, alkaline phosphatase and bilirubin were more severe or occurred exclusively in dogs receiving 800 mg/m2 + WBH. Since these changes were attributable to marked AUC increases, which occurred secondary to repeated exposure to 800 mg/m2 lonidamine during WBH, 400 mg/m2 was identified as the maximum tolerable dose to be administered intravenously to dogs during WBH.  相似文献   
993.
Vascular calcifications are common in uremic patients whereas calciphylaxis is rare. We report the case of a 45-year-old woman on chronic hemodialysis since 1977. She had a subtotal parathyroidectomy in 1985, aortic and mitral valve replacement in 1986, and has been treated since then with nicoumalone. In June 1991, she presented with repeated, painful cutaneous necrosis suggesting panniculitis. A skin biopsy showed lobular panniculitis and evidence of calciphylaxis. There was an obvious biological hyperparathyroidism. Protein C functional level was in the normal range whereas protein S functional level was low, i.e. 42%. The patient underwent cervical surgery to remove two parathyroid glands, and daily hemodialysis sessions. Despite this treatment, cutaneous necrosis progressed with superinfection. A few weeks later, the patient died from a septic shock after a myocardic infarction. Necropsy was not performed.  相似文献   
994.
995.
996.
The efficacy and safety of optimally titrated once-daily (CD) and twice-daily (SR) diltiazem were compared in 111 patients with mild to moderate systemic hypertension [seated diastolic blood pressure (DBP) > or = 95 mmHg and < or = 114 mmHg] in a multicenter, randomized, double-blind, placebo run-in, parallel-group trial. Following a 4 week washout and placebo-controlled run-in period, patients were randomized to receive diltiazem CD 180 mg and matching placebo (n = 54), or diltiazem SR 90 mg bid (n = 57). Total daily doses were titrated from 180 mg to 360 mg to achieve a goal of seated DBP < 90 mmHg during a 6 week titration period. The patients continued to receive their optimal dose for a 6 week follow-up period. Ninety-six (96) patients (diltiazem CD: 47, diltiazem SR: 49) completed the study protocol, with 60% of the diltiazem CD and 55% of the diltiazem SR patients achieving the goal of seated DBP of < 90 mmHg (p = 0.685). Although significant decreases occurred in seated and standing measurements of diastolic and systolic BP and heart rate with treatment in both groups, there were no significant differences between treatment groups. Both medications were well tolerated, with a similar frequency of adverse effects [diltiazem CD: 24/54 (37%) patients; diltiazem SR: 24/57 (42.1%) patients] with the most frequently reported adverse effects being headache and edema.  相似文献   
997.
Denaturant m values, the dependence of the free energy of unfolding on denaturant concentration, have been collected for a large set of proteins. The m value correlates very strongly with the amount of protein surface exposed to solvent upon unfolding, with linear correlation coefficients of R = 0.84 for urea and R = 0.87 for guanidine hydrochloride. These correlations improve to R = 0.90 when the effect of disulfide bonds on the accessible area of the unfolded protein is included. A similar dependence on accessible surface area has been found previously for the heat capacity change (delta Cp), which is confirmed here for our set of proteins. Denaturant m values and heat capacity changes also correlate well with each other. For proteins that undergo a simple two-state unfolding mechanism, the amount of surface exposed to solvent upon unfolding is a main structural determinant for both m values and delta Cp.  相似文献   
998.
The essential oil of Lippia multiflora was prepared by hydrodistillation of leaves and stalks and characterized by GC and mass spectroscopy. The oil was tested for antimalarial activity on in vitro cultures of Plasmodium falciparum (FcB1-Columbia chloroquine-resistant strain and F32-Tanzania chloroquine-sensitive strain). The dilutions inhibiting the in vitro growth of the parasite by 50% 24 and 72 hr after administration of the essential oil to the parasite culture were 1/12,000 and 1/21,000, respectively. When tested on a highly synchronized culture, the essential oil inhibited growth mostly at the trophozoite-schizont step, indicating a potential effect on the first nuclear division of the parasite.  相似文献   
999.
Pamidronate is a potent biphosphonate which modulates tumour-induced osteolysis (TIO) by inhibiting osteoclast-mediated bone resorption. In a phase II trial, 69 breast cancer patients with symptomatic progressive bone metastases were given infusions of pamidronate 60 mg over 1 or 4 h every 2 weeks for a maximum of 13 infusions or until progressive disease (PD) at any site. No other systemic anticancer therapy was allowed. Pain was measured using a visual analogue scale, mobility using a detailed eight-point questionnaire and analgesic intake using a six-point scale. Improvements in pain, mobility and analgesic scores occurred in 61, 50 and 30% of patients, respectively, with 33, 21 and 16% achieving a 40% improvement for > or = 8 weeks. At trial discontinuation, baseline levels of pain and mobility had improved by 27% (P = 0.001) and 20% (P = 0.004), respectively, despite a one category reduction in analgesic intake in 27% of patients. Using this relatively high dose of pamidronate, symptomatic response was independent of the number of bone metastases and also of infusion rate. The infusions were well tolerated with no major toxicities reported. Pamidronate infusions provide useful palliation for breast cancer patients with symptomatic bone metastases.  相似文献   
1000.
The choice of soft pulse shapes for chemical shift selective excitation in chemical shift imaging is discussed. In the presence of inhomogeneities in the static magnetic field resulting from susceptibility anomalies, it is important to optimise pulse bandshape and frequency offset as well as bandwidth, in order to minimize artefacts arising from excitation of unwanted resonances. A comparison of the use of Gaussian and sinc shaped excitation pulses in the chemical shift micro-imaging of grapes serves to illustrate some of the effects that may be observed.  相似文献   
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