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排序方式: 共有969条查询结果,搜索用时 15 毫秒
1.
S J Lavine D P Shreiner V Krishnaswami M Amidi W P Follansbee 《Clinical nuclear medicine》1986,11(3):168-174
Accurate count-based radionuclide estimates of left ventricular volume without the use of a blood sample have not been well described. Resting gated blood pool scans were obtained within 24 hours of catheterization in 31 patients (group 1), and simultaneously with thermodilution cardiac outputs in 29 other patients (group 2) at rest and during an induced-volume change (intervention). End-diastolic and end-systolic volumes were calculated from the single-plane angiogram in Group 1 and from the combination of thermodilution stroke volume and radionuclide ejection fraction in group 2. Excellent correlations were noted between scintigraphic counts and angiographic volumes (r = 0.964), between scintigraphic counts and thermodilution-derived volumes (r = 0.979), and between interventional scintigraphic counts and interventional thermodilution-derived volumes (r = 0.941). Thermodilution and scintigraphic volume changes during the intervention were well correlated (r = 0.85). Accurate count based estimates of left ventricular volume without a blood sample are feasible at rest and during an intervention. 相似文献
2.
Dulari S. Thilakarathne Carol A. Hartley Andrés Diaz-Méndez José A. Quinteros Omid Fakhri Mauricio J. C. Coppo 《Avian pathology》2020,49(4):369-379
ABSTRACT Latency is an important feature of infectious laryngotracheitis virus (ILTV) yet is poorly understood. This study aimed to compare latency characteristics of vaccine (SA2) and field (CL9) strains of ILTV, establish an in vitro reactivation system and examine ILTV infection in peripheral blood mononuclear cells (PBMC) in specific pathogen-free chickens. Birds were inoculated with SA2 or CL9 ILTV and then bled and culled at 21 or 35 days post-inoculation (dpi). Swabs (conjunctiva, palatine cleft, trachea) and trigeminal ganglia (TG) were examined for ILTV DNA using PCR. Half of the TG, trachea and PBMC were co-cultivated with cell monolayers to assess in vitro reactivation of ILTV infection. ILTV DNA was detected in the trachea of approximately 50% of ILTV‐inoculated birds at both timepoints. At 21?dpi, ILTV was detected in the TG only in 29% and 17% of CL9- and SA2-infected birds, respectively. At 35?dpi, ILTV was detected in the TG only in 30% and 10% of CL9- and SA2-infected birds, respectively. Tracheal organ co-cultures from 30% and 70% of CL9- and SA2-infected birds, respectively, were negative for ILTV DNA at cull but yielded quantifiable DNA within 6 days post-explant (dpe). TG co-cultivation from 30% and 40% of CL9-and SA2-infected birds, respectively, had detectable ILTV DNA within 6 dpe. Latency characteristics did not substantially vary based on the strain of virus inoculated or between sampling timepoints. These results advance our understanding of ILTV latency and reactivation. RESEARCH HIGHLIGHTS
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Following inoculation, latent ILTV infection was detected in a large proportion of chickens, irrespective of whether a field or vaccine strain was inoculated.
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In vitro reactivation of latent ILTV was readily detected in tracheal and trigeminal ganglia co-cultures using PCR.
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ILTV latency observed in SPF chickens at 21 days post-infection was not substantially different to 35 days post-infection.
3.
Tabatabai M Segal R Amidi M Caines M Kirimli B Stremple JF 《Journal of neurosurgical anesthesiology》1990,2(4):266-271
The perioperative changes in the serum concentration of creatine phosphokinase (CPK) and its isoenzymes MM, MB, and BB and of lactic dehydrogenase (LDH) and its isoenzymes LDH1 to LDH5 were determined during craniotomy in order to distinguish operation-induced changes in these enzymes from those due to acute myocardial infarction and malignant hyperthermia. Twenty-eight male patients, 29 to 76 years of age (mean +/- SD = 58 +/- 13.2 years), undergoing craniotomy for tumor reseaction (n = 26) or cerebral artery aneurysm clipping (n = 2) were included in this study. Ten serial blood samples were obtained from each patient: one sample before and another after induction of anesthesia, and eight samples after the incision, over a period of 70 h. The preinduction serum CPK level of 97 +/- 32 U/L (mean +/- SD) increased gradually and significantly and reached the peak level of 542 +/- 116 U/L 34 h after incision (p <0.05). Whereas all of the CPK isoenzymes increased in terms of U/L after incision, only the MM fraction (expressed as percent of total CPK) increased, and the MB and BB fractions (expressed as percent of total CPK) decreased. The preinduction serum LDH level of 150 +/- 42 U/L (mean +/- SD) increased gradually after incision and reached the peak level of 210 +/- 32 U/L 58 h after incision (p <0.05). LDH2 as a percent of total LDH decreased significantly, but the LDH1/LDH2 ratio did not change. LDH4 and LDH5, as percents of total LDH, increased significantly. The large increases in total serum CPK and the concomitant decrease in MB percent after craniotomy may minimize and/or mask the percentage increase in the MB level following acute myocardial infarction. The perioperative serum CPK level as a marker in the diagnosis of malignant hyperthermia should be interpreted in light of the present results and in conjunction with clinical symptomatology. 相似文献
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Fatemeh V. Zohoori Ralph M. Duckworth Narges Omid William T. O'Hare Anne Maguire 《European journal of oral sciences》2012,120(5):415-421
Fluoridated toothpaste is effective for dental caries control, yet may be a risk factor for dental fluorosis. This study aimed to quantify fluoride ingestion from toothpaste by children and to investigate the effects of age, gender, and social class on the amount of fluoride ingested per toothbrushing session. Sixty‐one children, 4–6 yr of age, were recruited: 38 were from low socio‐economic (LSE) areas of Newcastle, UK, and 23 were from high socio‐economic (HSE) areas of Newcastle, UK. All expectorated saliva, rinse water (if used), and residual toothpaste were collected after brushing at home and were analysed for fluoride. Of the children, 74% and 69% from HSE and LSE areas, respectively, claimed that they brushed twice per day. The mean (SD) weight of toothpaste dispensed was 0.67 (0.36) g. The mean (SD) amount of fluoride ingested per toothbrushing session and per day was 17.0 (14.7) and 29.3 (32.8) μg kg?1 of body weight, respectively. Daily fluoride intake per kilogram of body weight did not differ significantly between children from LSE and HSE areas. Fluoride intake per toothbrushing session was significantly influenced by weight of toothpaste, its fluoride concentration, and the child's age. Whilst the average amount of toothpaste used per toothbrushing session was more than twice the recommended amount (of 0.25 g), only one child had a daily fluoride intake that exceeded the tolerable upper intake level of 0.1 mg kg?1 of body weight for this age group. 相似文献
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Parissa Karrari Omid Mehrpour Mohammad Abdollahi 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2012,20(1):1-17
Lead is an old environmental metal which is presented everywhere and lead poisoning is an important health issue in many countries in the world including Iran. It is known as a silent environmental disease which can have life-long adverse health effects. In children, the most vulnerable population, mental development of children health effects is of the greatest influence. Low level lead exposure can significantly induce motor dysfunctions and cognitive impairment in children. The sources of lead exposure vary among countries. Occupational lead exposure is an important health issue in Iran and mine workers, employees of paint factories, workers of copying centers, drivers, and tile making factories are in higher risk of lead toxicity. Moreover lead processing industry has always been a major of concern which affects surface water, drinking waters, and ground waters, even water of Caspian Sea, Persian Gulf and rivers due to increasing the number of industries in vicinity of rivers that release their waste discharges into river or sea. In addition, lead contamination of soil and air especially in vicinity of polluted and industrialized cities is another health problem in Iran. Even foods such as rice and fishes, raw milk, and vegetables which are the most common food of Iranian population are polluted to lead in some area of Iran. Adding lead to the opium is a recently health hazard in Iran that has been observed among opium addicts. There are few studies evaluated current status of lead exposure and toxicity in the Iranian children and pregnant women which should be taken into account of authorities. We recommend to identify sources, eliminate or control sources, and monitor environmental exposures and hazards to prevent lead poisoning. 相似文献
9.
Seyed Mostafa Nachvak Shima Moradi Javad Anjom-shoae Jamal Rahmani Morteza Nasiri Vahid Maleki Omid Sadeghi 《Journal of the Academy of Nutrition and Dietetics》2019,119(9):1483-1500.e17
ObjectiveWe conducted a systematic review and dose–response meta-analysis of prospective studies to summarize findings on the associations between intakes of soy, soy isoflavones, and soy protein and risk of mortality from all causes, cancers, and cardiovascular diseases.MethodsOnline databases were systematically searched to identify relevant articles published earlier than May 2018. We applied restricted cubic splines using random-effects analysis to assess dose–response associations. Between-study heterogeneity was assessed by I2 value and Cochrane Q test. Potential publication bias was assessed by visual inspection of funnel plots and Begg regression test.ResultsIn total, 23 prospective studies with an overall sample size of 330,826 participants were included in the current systematic review and the meta-analysis. Soy/soy products consumption was inversely associated with deaths from cancers (pooled relative risk 0.88, 95% CI 0.79 to 0.99; P=0.03; I2=47.1%, 95% CI 0.0% to 75.4%) and cardiovascular diseases (pooled effect size: 0.85, 95% CI 0.72 to 0.99; P=0.04; I2=50.0%, 95% CI 0.0% to 77.6%). Such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality. In addition, higher intake of soy was associated with decreased risk of mortality from gastric, colorectal, and lung cancers as well as ischemic cardiovascular diseases. Participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category. We also found that a 10-mg/day increase in intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and also breast cancer respectively. Furthermore, a 12% reduction in breast cancer death was indicated for each 5-g/day increase in consumption of soy protein. However, intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.ConclusionsSoy and its isoflavones may favorably influence risk of mortality. In addition, soy protein intake was associated with a decreased risk in the mortality of breast cancer. Our findings may support the current recommendations to increase intake of soy for greater longevity. 相似文献
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