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1.
Abstract The pain of cluster headache attacks is severe, excruciating and selectively responsive to subcutaneous sumatriptan. Serious cardiovascular events attributed to sumatriptan are extremely rare and have most often been reported in patients at significant cardiovascular risk, or in overt cardiovascular disease. They also have occurred, however, in patients without evidence of cardiovascular disease. We describe a 42-year-old man with episodic cluster headache without history of coronary artery disease who was admitted to our coronary care unit for acute myocardial infarction after 3 h of subcutaneous injection of sumatriptan. During hospitalisation cluster headache attacks were successfully treated with e.v. indomethacin.  相似文献   
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Spontaneous arterio-venous fistulae of the vertebral artery are rare. These lesions mainly affect the upper cervical area, and are usually asymptomatic, or may present as small, often pulsatile, cervical masses with vascular murmurs. The authors report on two cases in which the presumptive diagnosis, suggested by venous digital subtraction angiography, was then confirmed by selective angiography. In both cases an intravascular approach with detachable balloons and particulate substances was carried out, with good anatomical and functional results. Problems related to diagnosis, pathophysiology of symptoms, indications for treatment and embolization techniques are discussed.  相似文献   
4.
Melatonin suppression by bright light was investigated in 15 drug-free euthymic bipolar patients and control subjects matched for age and sex with the patients. There were no differences between groups on the extent of melatonin suppression by 500 lux bright light administered between 0200h and 0400h. These results do not support the hypothesis that melatonin suppression by bright light is a reliable trait marker in recovered bipolar patients.  相似文献   
5.
The energy cost of walking or running on sand   总被引:1,自引:0,他引:1  
Summary Oxygen uptake ( O2) at steady state, heart rate and perceived exertion were determined on nine subjects (six men and three women) while walking (3–7 km · h–1) or running (7–14 km · h–1) on sand or on a firm surface. The women performed the walking tests only. The energy cost of locomotion per unit of distance (C) was then calculated from the ratio of O2 to speed and expressed in J · kg–1 · m–1 assuming an energy equivalent of 20.9 J · ml O2 –1. At the highest speedsC was adjusted for the measured lactate contribution (which ranged from approximately 2% to approximately 11% of the total). It was found that, when walking on sand,C increased linearly with speed from 3.1 J · kg–1 · m–1 at 3 km · h–1 to 5.5 J · kg–1 · m–1 at 7 km · h–1, whereas on a firm surfaceC attained a minimum of 2.3 J · kg–1 · m–1 at 4.5 km · h–1 being greater at lower or higher speeds. On average, when walking at speeds greater than 3 km · h–1,C was about 1.8 times greater on sand than on compact terrain. When running on sandC was approximately independent of the speed, amounting to 5.3 J · kg–1 · m–1, i.e. about 1.2 times greater than on compact terrain. These findings could be attributed to a reduced recovery of potential and kinetic energy at each stride when walking on sand (approximately 45% to be compared to approximately 65% on a firm surface) and to a reduced recovery of elastic energy when running on sand.  相似文献   
6.
BACKGROUND: Chronic airway inflammation is a fundamental feature of bronchial asthma, which is characterized by the accumulation and activation of inflammatory cells, such as mast cells and eosinophils, that are tightly regulated by TH2 cytokines and chemokines. Recently, we demonstrated, in a murine model of asthma with immunosuppressed mice reconstituted with antigen-specific IgE or IgG1 antibodies, that IgE, but not IgG1, participates in potentiation of airway inflammation and induction of airway hyperreactivity (AHR). The IgG1 antibody, however, did not elicit passive cutaneous anaphylactic reactions, which was in contrast to IgE. OBJECTIVES: Because 2 types of murine IgG1 have been demonstrated with regard to anaphylactic activity, the present experiments were undertaken to determine the role of anaphylactic and nonanaphylactic IgG1 antibodies in the development of antigen-induced eosinophilia and AHR in this model. METHODS: Dinitrophenyl-conjugated, heat-coagulated hen's egg white was implanted in immunosuppressed mice reconstituted with anaphylactic or nonanaphylactic IgG1. Intratracheal challenge with aggregated dinitrophenyl-ovalbumin was performed on day 14, and lung inflammatory and mechanical parameters were evaluated after 48 hours. RESULTS: Our results demonstrated that reconstitution of immunosuppressed mice with anaphylactic IgG1 antibodies in contrast to nonanaphylactic IgG1 antibodies potentiates their ability to have pulmonary eosinophilic inflammation and AHR. IL-5 and eotaxin levels in bronchoalveolar lavage fluid from anaphylactic IgG1-reconstituted mice were also higher than those in nonanaphylactic IgG1-reconstituted mice. CONCLUSIONS: These results indicate that the anaphylactic property of murine IgG1 molecules is essential for their capacity to enhance lung eosinophilic inflammation and to induce AHR.  相似文献   
7.
Heterogeneity of guinea-pig homocytotropic antibodies   总被引:5,自引:0,他引:5  
A. Perini  I. Mota 《Immunology》1972,22(5):915-923
It is suggested that guinea-pigs produce three different homocytotropic antibodies that can be distinguished by their physicochemical and biological properties. One has the properties of an IgG antibody, is heat and mercaptoethanol resistant and persists in the passively sensitized skin for not more than 72 hours. The other has the properties of an IgE antibody, is heat and mercaptoethanol labile and persists in the passively sensitized skin for at least 20 days. The third antibody is heat stable and mercaptoethanol labile and persists in the passively sensitized skin for more than 72 hours but less than 1 week. This antibody was partially separated from γ1 antibody by chromatography on DEAE cellulose and may represent a distinct segment of the γ1 antibody population. All three antibodies were able to sensitize guinea-pig mast cells and cause degranulation of these cells on reaction with antigen. Antihistamines produced complete inhibition of PCA reactions induced with all three types of antibodies but were much less efficient in inhibition PCA reactions induced with γ1 antibody obtained from hyperimmune serum.  相似文献   
8.
Exploring an alternative to improve the clinical management of hypertension, we tested the hypothesis that food supplementation with coconut oil (EVCO), alone or combined with aerobic exercise training, could exert an antihypertensive effect (primary outcome) in patients with stage 1 hypertension. Forty-five hypertensive volunteers of both genders participated in a placebo-controlled clinical trial. The volunteers were submitted to 24-hour ambulatory blood pressure monitoring, analysis of blood pressure variability (BPV), measurement of serum malondialdehyde (MDA) and nutritional assessment. Results indicate that EVCO consumption had no adverse effects. The supplementation did not increase the caloric intake compared with placebo, and the dietary constituents were similar between groups, except for the saturated fats, especially lauric acid. The analysis of blood pressure indicated absence of antihypertensive effect of EVCO alone or combined with physical training. Furthermore, no effects on blood pressure variability and oxidative stress were observed in the supplemented hypertensive patients. Thus, despite the results observed in pre-clinical studies, the current clinical study did not provide evidence to support the use of coconut oil as an adjuvant in the management of hypertension in humans.  相似文献   
9.
IntroductionLiver transplantation is the standard treatment for end-stage liver disease. Brazil holds the third highest number of liver transplants performed per year, but center maldistribution results in high discrepancies in accessing this treatment. In 2012, an interstate partnership successfully implemented a new liver transplantation program in the middle west of Brazil. Here, we report the results of the first 500 liver transplants performed in this new program and discuss the impacts of a new transplant center in regional transplantation dynamics.MethodsWe reviewed data from the first 500 consecutive deceased donor liver transplants performed in the new program during an 8-year period. We analyzed data on patients’ clinical and demographic profiles, postoperative outcomes, and graft and recipient survival rates. Univariate survival analysis was conducted using log-rank tests to compare the groups.ResultsAlmost half (48%) of the procured organs and 40% of the recipients transplanted in our center were from outside our state. Recipient 30-day mortality was 9%. Overall recipient survival at 1 year and 5 years was 85% and 80%, respectively. Mortality was significantly associated with higher Model for End-Stage Liver Disease (P < .001) but not with the presence of hepatocellular carcinoma (P = .795).DiscussionThe new transplantation program treated patients from different regions of Brazil and became the reference center in liver transplantation for the middle west region. Despite the recent implementation, our outcomes are comparable to experienced centers around the world. This model can inspire the creation of new transplantation programs aiming to democratize access to liver transplantation nationwide.  相似文献   
10.
The home prothrombin time/international normalized ratio (PT/INR) self-management could be convenient for patients, enhancing treatment compliance and improving the quality of the oral anticoagulation. However, patient self-management (PSM) of oral anticoagulation may not be feasible for up to half of the patients due to cognitive or educational issues. In the present study, we aimed to evaluate the feasibility of a PSM program in a public health medical center that provides care for low-income patients. We also aimed to determine the accuracy of individual point-of-care devices (CoaguChek XS®) during long-term of home manipulation. Patients’ time-in-therapeutic range (TTR) and perception of quality of life, were evaluated at scheduled study-visits to the center. Additionally, the accuracy of individual CoaguChek XS® was evaluated in comparison to the standard automated coagulometer at scheduled study-visits to the center. Twenty-five patients were included in the PSM program. The median TTR of patients was 75 % before inclusion, 72 % at 3 months, 75 % at 6 months and 100 % at 12 months after the beginning of self-management (P = 0.14).The median DASS scores were 64, 63, 61.5 and 71.5 before inclusion and at 3, 6 and 12 months, respectively (P = 0.09). One hundred paired INR values were obtained. Correlation between INR values delivered by individual CoaguChek XS® and the automated coagulometer was 94 % and the mean result bias was 0.07 INR units. The coefficient of correlation and the mean bias between methods was stable during 24 months of follow-up. The present study suggests that PSM is feasible for patients treated in the public health system and that the results delivered by CoaguChek XS® have long-term reliability.  相似文献   
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