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21.
Syncopes due to compulsive respiratory stereotypies were studied in eight patients with autistic features. Most had been referred for episodes thought to be intractable epileptic seizures. Polygraphic recording showed two types of syncope, one induced by prolonged apnea and the other by a prolonged Valsalva maneuver. Fenfluramine, 1.5–3 mg/kg per day, was given in an open trial. In four of five cases with frequent Valsalva maneuvers, respiratory stereotypies and syncopes were suppressed for 2–18 months. Patients with periodic apneas were more severely retarded and had less clear benefit. Side effects consisted of dose-dependent sedation and mild weight loss which stabilized without interrupting treatment. We suggest that these syncopes are volitional and may be associated with pleasant sensations. A double-blind placebo-controlled trial of fenfluramine seems warranted in such patients.  相似文献   
22.
To estimate the evolution of amyloid in tissue, we studied abdominal fat aspirates of cases with familial amyloidotic polyneuropathy (FAP) longitudinally at regular intervals between 1994 and 2006. In 22 cases (13 carriers and nine patients) not yet transplanted median follow-up was 3.3 years (range 0.4-11.3). We found a significant increase in the amyloid grade of fat tissue from 2+ to 4+ and from 0 to 4+ in two of three subjects with follow-ups of >7 years, after 7 and 11 years, respectively. All other subjects remained negative or did not show a significant change. In 11 liver transplant patients, follow-up with fat aspirate was available with a median duration of 3.1 years (range 1.0-10.1). A comparison was made with cardiac amyloid as judged by the cardiac septum diameter and the serum NT-ProBNP (N-terminal pro-B-type natriuretic peptide) level. No stable increase of amyloid in fat was seen in any patient. A stable decrease of amyloid grade was seen in one patient 5 years after transplantation. In contrast, the cardiac septum diameter increased >or=4 mm in six of the 11 transplant patients. Our study shows the diagnostic utility of a regularly repeated fat aspirate in carriers at risk for the development of ATTR amyloidosis. Evolution of amyloid deposition in fat tissue is very gradual. After liver transplantation, amyloid deposition in fat tissue seems to stabilize and may even decrease in the long term, whereas amyloid deposition in cardiac tissue appears to be progressive.  相似文献   
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The objective of this study was to develop and verify a new technique for monitoring the progression of osteoarthritis (OA) by combining a rat model with the imaging modality optical coherence tomography (OCT). Time-sequential, in vivo, OCT imaging was performed on the left femoral condyles of 12 Wistar rats following sodium-iodoacetic acid-induced OA progression. The right femoral condyles (untreated) were also imaged and served as controls. Imaging was performed on days 0, 10, 20, 30, and 60 with an OCT system capable of acquiring images at four frames per second and an axial resolution of 5 microm. Progressive changes were analyzed using an OA scoring system. OCT successfully identified progressive cartilage degeneration as well as alteration of the cartilage/bone interface. Significant changes to both of these structures were observed in the sodium-iodoacetic acid-injected condyles. Structural changes detected with OCT were confirmed histologically. OCT in combination with a well-known model used in arthritis research represents a powerful tool for following degenerative joint disease progression in a given animal by detecting changes to the cartilage/bone interface and articular cartilage.  相似文献   
26.
Study Objective . To determine if one commercial extended-release formulation of nifedipine (Adalat CC) is as effective as another (Procardia XL) in controlling blood pressure over 24 hours. Design . Open-label, randomized, crossover study. Setting . University-affiliated family medicine clinic. Patients . Fifteen patients with stage 1–4 primary hypertension. Interventions . Procardia XL or Adalat CC once/day was titrated to achieve blood pressure control. The effective dose was continued for 4 weeks, washed out for 1 week, and reinstituted with other study drug. Measurements and Main Results . Twenty-four-hour ambulatory blood pressure was recorded the conclusion of each treatment phase. Treatment phases were compared for mean 24-hour blood pressure, mean daytime (6:00 a.m.–10:00 p.m.) and mean nighttime blood pressure, and mean blood pressure load (percentage of blood pressure measurements < 140/90 mm Hg daytime and > 120/80 mm Hg nighttime). Thirteen patients completed the study. No statistically significant difference was seen in mean 24-hour blood pressure (138/86 mm Hg for Procardia XL vs 137/85 mm Hg for Adalat CC), daytime or nighttime blood pressure, or blood pressure load. Two patients experienced clinically significant adverse effects while taking Adalat CC. Conclusions . In these patients with primary hypertension, Adalat CC was as effective as Procardia XL at controlling blood pressure for 24 hours. Blood pressure, heart rate, and adverse effects should be monitored 2–4 weeks after any exchange of Adalat CC for Procardia XL.  相似文献   
27.
Copolymerization of propene with 1-octene (1 mol/1 mol) was performed in toluene at 40°C in the presence of homogeneous methylaluminoxane (MAO)-activated ansa-metallocenes in order to study the role of benzannelation and 2-methyl-substitution of the silylene-bridged bisindenyl ligand on comonomer incoporation, molecular mass, molecular mass distribution, and end groups. While 2-methyl-substitution promoted higher degree of polymerization without affecting copolymerization parameters, benzannelation improved markedly 1-octene incorporation. Only with MAO-activated rac-Me2Si(2-MeBenz[e]Ind)2ZrCl2 catalysts vinylidene end groups were formed exclusively. Molecular weight distribution remains narrow in all experiments.  相似文献   
28.
In a double-blind, randomized, placebo-controlled cross-over study, we investigated in seven patients with chronic renal failure the effect of conjugated estrogens (0.6 mg/kg/day for 5 days) on template bleeding time and on thromboxane A2 (TxA2), beta-thromboglobulin (beta-TG) and prostacyclin (PGI2) concentrations in blood emerging from the template bleeding time incisions. Administration of conjugated estrogens resulted in a significant shortening of the bleeding time in six out of seven patients with a maximum effect 7 and/or 14 days following treatment. Both TxA2 (measured as thromboxane B2, TxB2) and beta-TG release in bleeding time blood were significantly higher following administration of conjugated estrogens as compared to placebo administration. No difference was seen in endothelial PGI2 (measured as 6-keto-prostaglandin F1 alpha) formation when patients were treated with conjugated estrogens as compared to placebo administration over the 28 day observation period. We conclude that in patients with chronic renal failure, infusion of conjugated estrogens results in a significant shortening of the bleeding time together with an increase in platelet reactivity, as indicated by an increase of TxA2 and beta-TG concentration in the microvasculature. No effect was seen on PGI2 production, thereby excluding a major effect on vascular prostaglandin metabolism.  相似文献   
29.
A rare case of prosthetic valve endocarditis caused by Micrococcus luteus is described and compared with the few cases reported in the literature, as well as the clinical features, microbiological profile, therapy, and prognosis of common prosthetic valve endocarditis. Micrococcus luteus is a constituent of the normal human buccal bacterial flora which forms yellowish colonies and appears as a gram-positive coccus typically arranged in tetrades. Although of low virulence, the germ may become pathogenic in patients with impaired resistance, colonizing the surface of heart valves. In contrast to staphylococci (for which it may easily be mistaken) it is usually penicillin-sensitive. However, the most promising antibiotic regimen proposed for treatment of Micrococcus luteus seems to be a combination of vancomycin, amikacin, and rifampicin. If the infection leads to severe hemodynamic alterations, however, valve replacement may become necessary similar to the situation in prosthetic valve endocarditis caused by more aggressive and highly resistant bacteria.  相似文献   
30.
We have reported that female rats have more axons in the splenium of the corpus callosum than do male rats (12). To determine if the greater number of axons found in female rats might be reflected in a larger distribution of callosal projection neurons, horseradish peroxidase (HRP) was injected into the visual cortex of 55-65-day-old rats of both sexes that had been housed in a complex environment since weaning. The pattern of labeled neurons was examined in tangential sections in the cortex contralateral to the injection site, and three-dimensional reconstructions were quantified at the area 17/18a border and in area 18b. Male and female rats were found to have indistinguishable distributions of labeled callosal projection neurons. The present study failed to find an obvious difference in the distribution of projection neurons as the basis for the sex differences in axon number, but because of the limitations of tracing techniques, subtle differences cannot be excluded.  相似文献   
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