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排序方式: 共有9016条查询结果,搜索用时 31 毫秒
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Estefany I. Medina-Reyes Carolina Rodríguez-Ibarra Daniel Díaz-Urbina Alejandro Déciga-Alcaraz Normal L. Delgado-Buenrostro Yolanda I. Chirino José Pedraza-Chaverri 《Journal of applied toxicology : JAT》2022,42(8):1411-1419
Food-grade titanium dioxide (E171) is widely used as a food additive, and it is known that after oral consumption, E171 is translocated into the bloodstream reaching the highest titanium level at 6 h. E171 is accumulated in some organs triggering toxicity, but the effects on the blood parameters after oral consumption have been less studied. Recently, evidence shows that oral exposure to E171 induces behavioral signs of anxiety and depression. The relation between blood alterations and psychiatric disorders has been previously demonstrated. However, the oral exposure to E171 effects on alterations in blood parameters and effects linked to alterations in animal behavior has not been explored. In this short communication, we aimed to investigate the effects of E171 on specific blood parameters (hematocrit, hemoglobin, number of erythrocytes, and leukocytes) and anxiety and compulsive-like behavior in males and females orally exposed to ~5 mg/kg for 4 weeks. The results showed that E171 decreased hematocrit and hemoglobin in male but not in female mice while leukocyte and erythrocyte count remained unaltered. Oral consumption of E171 decreased the levels of anxiety-like behavior in females but not in male mice, while compulsive-like behavior was increased in both male and female mice. 相似文献
3.
Yolanda Carrascal PhD Gregorio Laguna PhD Miriam Blanco MD Bárbara Segura MD Iciar Martínez-Almeida MD 《Journal of cardiac surgery》2020,35(2):457-459
Gray platelet syndrome (GPS) is a rare (<1/1 000 000) and inherited platelet function disorder characterized by macrothrombocytopenia, α-granule deficiency, and hemorrhages. Bleeding intensity does not correlate with platelet count nor with functional test results. We hereby describe the perioperative bleeding prevention and management of a patient with GPS requiring multiple redo cardiac surgeries. 相似文献
4.
Steven V Koenen Anjoke J M Huisjes Jules Dings Yolanda van der Graaf Gerard H A Visser Hein W Bruinse 《The journal of maternal-fetal & neonatal medicine》2006,19(2):93-99
OBJECTIVE: To determine if there is a diurnal pattern in the clinical symptoms of HELLP (Hemolysis, Elevated Liver enzymes, Low Platelets) syndrome. STUDY DESIGN: A retrospective study was performed in 134 pregnancies complicated by HELLP syndrome. The medical records were reviewed to describe each HELLP episode. Time of day was divided into three periods, day, evening, and night. The following parameters were categorized according to the time of day: onset of symptoms, consultation by the doctor, initial blood sampling, diagnosis and decrease of symptoms. Biochemical parameters at clinical presentation and consecutive changes within 24 h were recorded. RESULTS: In 65 pregnancies 77 HELLP episodes were well documented. Times of onset of symptoms and consultation by the doctor were significantly higher during the evening and night (p < 0.001), whereas times of diagnosis and decrease of symptoms occurred significantly more during the day (p < 0.001). In only 49.3% of the cases were diagnostic laboratory criteria met at clinical presentation. This was mainly due to platelet values in excess of 100 x 10(9)/l. Several hours later (median 8 h, range 2-23) the decrease in platelets occurred. CONCLUSIONS: A diurnal pattern exists in the clinical symptoms of HELLP syndrome that is characterized by an exacerbation during the night and recovery during the day. There is a considerable delay between the onset of symptoms and the fulfillment of diagnostic laboratory criteria. 相似文献
5.
Outcomes at 3 years of a prospective pilot study of Campath-1H and sirolimus immunosuppression for renal transplantation 总被引:2,自引:0,他引:2
Rolf N. Barth Christina A. Janus Christine A. Lillesand Nancy A. Radke John D. Pirsch Bryan N. Becker Luis A. Fernandez L. Thomas Chin Yolanda T. Becker Jon S. Odorico Anthony M. D''Alessandro Hans W. Sollinger Stuart J. Knechtle 《Transplant international》2006,19(11):885-892
Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor. 相似文献
6.
Therapeutic Consequences of Variation in Intraarterial Pressure Measurements After Iliac Angioplasty
Eric Tetteroo Cees Haaring Andries D. van Engelen Yolanda van der Graaf Willem P.T.M. Mali 《Cardiovascular and interventional radiology》1997,20(6):426-430
Purpose: To assess the accuracy of intraarterial measurement of transstenotic pressure gradients for the detection of hemodynamically
suboptimal iliac angioplasty.
Methods: In 14 patients, referred for diagnostic angiography, mean pressure gradients in the aorta and iliac artery were obtained
twice, using a double-sensor pressure catheter. Additional iliac measurements were performed during pharmacologically induced
flow augmentation. Repeatability was assessed by calculation of the mean difference plus standard deviation (MD ± SD) and
repeatability coefficient (2 × SD). These results were extrapolated to 137 iliac angioplasty procedures with secondary stenting
where there was a residual pressure gradient > 10 mmHg.
Results: MD ± SD for repeated measurements at rest and during flow augmentation were 0 ± 2 mmHg and 1 ± 3 mmHg, respectively. Repeatability
coefficients were 3 and 6 mmHg. Mean pressure gradients after hemodynamically insufficient angioplasty were 8 ± 7 mmHg at
rest and 17 ± 5 mmHg following vasodilatation. Inaccurate pressure recordings may have led to inappropriate stent placement
in less than 2.5%, and inappropriate denial of stent placement in less than 5% of the lesions.
Conclusion: Variability of intraarterial pressure measurements has little consequence in the detection of hemodynamically significant
stenosis after angioplasty.
Received: 0/00/00/Accepted: 0/00/00 相似文献
7.
Increased production of peroxidation products associated with cardiac operations. Evidence for free radical generation 总被引:7,自引:0,他引:7
D Royston J S Fleming J B Desai S Westaby K M Taylor 《The Journal of thoracic and cardiovascular surgery》1986,91(5):759-766
We investigated the degree and time course of neutrophil sequestration into human lungs during cardiac operations. At the same time, measurement of the concentration of peroxidation products in the plasma was used as an index of oxidant free radical activity. The study was performed in two groups of patients. Group A (n = 11) had studies extending over the entire operative period and showed a highly significant sequestration of neutrophils into the lung, together with a highly significant (p less than 0.001) rise in peroxidation products from 2.8 +/- 0.12 nmol/ml(mean +/- standard error of the mean)before bypass to a peak of 5.05 +/- 0.13 nmol/ml at the end of bypass. As these changes occurred only during the time after release of the aortic cross-clamp, we investigated this period in more detail in a second group of patients (Group B, n = 7). Results from this group showed that significant release of peroxidation products occurred at the same time as pulmonary neutrophil sequestration. This study has produced evidence of increased oxidant activity in the lung associated with cardiac operations. Nevertheless, it is not known whether the neutrophils sequestered into the lung alone induced the increased activity. Similarly, whether neutrophil-derived oxidant species are the sole cause of lung tissue injury remains unproved. 相似文献
8.
Amalia Moreno Concepción Montón Yolanda Belmonte Miguel Gallego Xavier Pomares Jordi Real 《Archivos de bronconeumologia》2009,45(4):181-185
ObjectiveThe objective of this study was to assess the causes of death and risk factors for mortality in a cohort of patients with severe chronic obstructive pulmonary disease (COPD).Patients and methodsWe studied 203 patients with severe COPD (forced expiratory volume in 1 second [FEV1] <50%), who were attended in our respiratory department day hospital (2001-2006). Clinical variables were recorded on inclusion, and clinical course and causes of death were retrospectively reviewed.ResultsThe mean (SD) age of patients was 69 (8) years and the mean FEV1 was 30.8% (8.2%). One-hundred and nine patients died (53.7%); death was attributed to respiratory causes in 72 (80.9%), with COPD exacerbation being the most frequent specific cause within this category (48.3%). During follow-up, 18.7% required admission to the intensive care unit (ICU). Survival at 1, 3, and 5 years was 80%, 53%, and 26%, respectively. The multivariate analysis showed that mortality was associated with age, stage IV classification according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD), cor pulmonale, and hospital admission during the year prior to inclusion. Need for admission to the ICU during follow-up was a factor independently associated with higher mortality.ConclusionsMortality in patients with severe COPD was high and exacerbation of the disease was one of the most frequent causes of death. Age, GOLD stage, cor pulmonale, prior admission to hospital, and need for admission to the ICU during follow-up were independent predictors of mortality. 相似文献
9.
Service profiles of general practitioners in Europe. European GP Task Profile Study. 总被引:1,自引:0,他引:1
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![点击此处可从《The British journal of general practice》网站下载免费的PDF全文](/ch/ext_images/free.gif)
BACKGROUND: General practice is the focal point of primary care. There are national differences in the structure and organization of practice, the relationship with secondary care is being redefined, and in some countries major changes are taking place. AIM: To describe and examine differences in the service profiles of general practitioners (GPs) in European countries. METHOD: Standardized questionnaires in the national languages were sent to samples of GPs in 1993. Four areas of service provision were measured: the GP's position in the first contact with selected health problems, the involvement in minor surgery and the application of medical procedures, disease management and preventive care. The importance of the gatekeeping role, remuneration system, and geographical region in Europe was examined by comparing scores in appropriate national groupings. RESULTS: Data were received from 7233 GPs in 30 countries. Most national samples were random and the average response rate was 47%. In countries where GPs have a gatekeeping role, they had a relatively stronger position as doctors of first contact. In those countries where GPs were usually self-employed, they had a stronger role in disease management and screening for blood cholesterol. In the examination of the three structural elements of health care, the most striking differences were evident in the comparison between eastern and western Europe. GPs throughout Europe had a comparatively small role in organized health education. CONCLUSION: The position of GPs is weak in eastern Europe and some Mediterranean countries, where service profiles have a limited range. General practice was more comprehensive where the doctors had a gatekeeping role. 相似文献
10.
Changes to the ocular biota with time in extended- and daily-wear disposable contact lens use. 总被引:3,自引:0,他引:3
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![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
F Stapleton M D Willcox C M Fleming S Hickson D F Sweeney B A Holden 《Infection and immunity》1995,63(11):4501-4505
Gram-negative bacteria may play a role in the etiology of certain soft contact lens (SCL)-related diseases. Contact lens (CL) wear may modify the normal ocular biota, providing a more favorable environment for potential pathogens. This study reports temporal changes in ocular biota in daily-wear (DW) and extended-wear (EW) disposable SCL use in experienced and neophyte wearers. Lid margin and bulbar conjunctival biota were sampled prior to CL fitting in 26 previous DW SCL users, 18 previous EW SCL users, and 26 neophytes. Wearers were fitted with an etafilcon A CL in one eye and a polymacon CL in the fellow eye. Lenses were worn on a daily basis by the 26 previous DW SCL wearers and on an EW basis by the remaining 44 subjects. The ocular biota was further sampled after 1, 3, 6, 9, and 12 months of wear. The ocular biota consisted of coagulase-negative staphylococci, Corynebacterium spp., Micrococcus spp., and Propionibacterium spp. Potential pathogens were rarely isolated at baseline. No significant trend of increasing ocular colonization was shown for extended CL wear. Lid and conjunctival colonization increased with DW SCL use (P < 0.001), although this increase occurred for nonpathogenic species only. Fewer potential pathogens were isolated from DW SCL than from EW SCL users (P < 0.05). The lid margin consistently showed greater colonization than the conjunctiva and may be a source of potential pathogens during CL wear. Hydrogel CL wear appears to modify the ocular biota. An increased number of commensal organisms were present in DW SCL use. EW SCL use altered the spectrum of organisms isolated. These alterations may suppress the normal ocular defense mechanisms and may be relevant in the pathogenesis of CL-related disease. 相似文献