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51.
Kevin Brooks Hanem Hasan Sridhar Samineni Venu Gangur Wilfried Karmaus 《Pediatric allergy and immunology》2007,18(7):621-624
Placental p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) concentration and cord blood atopic markers were determined in 19 neonates. Increased placental p,p'-DDE was associated with a statistically significant increase in cord plasma interleukin (IL)-13. Furthermore, both cord plasma IL-4/interferon (IFN)-gamma and IL-13/IFN-gamma ratios were significantly positively associated with placental p,p'-DDE concentration. 相似文献
52.
53.
Michael D Seidman Mumtaz J Khan Wen Xue Tang Wayne S Quirk 《Otolaryngology--head and neck surgery》2002,127(3):138-144
OBJECTIVES: Lecithin is a polyunsaturated phosphatidylcholine (PPC), which are high energy functional and structural elements of all biologic membranes. PPC play a rate-limiting role in the activation of numerous membrane-located enzymes, including superoxide dismutase and glutathione, which are important antioxidants protecting cell membranes from damage by reactive oxygen species (ROS). ROS-induced damage to mitochondrial DNA may lead to reduced mitochondrial function in the cochlea and resultant hearing loss. STUDY DESIGN AND SETTING: The effects of lecithin on aging and age-associated hearing loss were studied in rats by measuring hearing sensitivities using auditory brainstem responses (ABR). In addition, mitochondrial function as a measure of aging was assessed by determining mitochondrial membrane potentials using flow cytometry and by amplifying mitochondrial DNA deletions associated with aging. Harlan-Fischer rats aged 18 to 20 months (n = 14) were divided into 2 groups. The experimental group was supplemented orally for 6 months with lecithin, a purified extract of soybean phospholipid (Nutritional Therapeutics, Allendale, NJ). RESULTS: The data obtained were compared with the control group. ABRs were recorded at 2-month intervals and showed significant preservation of hearing sensitivities in the treated subjects. Flow cytometry revealed significantly higher mitochondrial membrane potentials in the treated subjects, suggesting preserved mitochondrial function. Finally, the common aging mitochondrial DNA deletion (mtDNA(4834)) were amplified from brain and cochlear tissue including stria vascularis and auditory nerve. This specific deletion was found significantly less frequent in all tissues in the treated group compared with the controls. CONCLUSION: These experiments support our hypothesis and provide evidence that lecithin may preserve cochlear mitochondrial function and protect hearing loss associated with aging. 相似文献
54.
Glyceraldehyde-3-phosphate dehydrogenase: Nuclear translocation participates in neuronal and nonneuronal cell death 下载免费PDF全文
Akira Sawa Adil A. Khan Lynda D. Hester Solomon H. Snyder 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(21):11669-11674
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein levels increase in particulate fractions in association with cell death in HEK293 cells, S49 cells, primary thymocytes, PC12 cells, and primary cerebral cortical neuronal cultures. Subcellular fractionation and immunocytochemistry reveal that this increase primarily reflects nuclear translocation. Nuclear GAPDH is tightly bound, resisting extraction by DNase or salt treatment. Treating primary thymocytes, PC12 cells, and primary cortical neurons with antisense but not sense oligonucleotides to GAPDH prevents cell death. Because cell-death-associated nuclear translocation of GAPDH and antisense protection occur in multiple neuronal and nonneuronal systems, we propose that GAPDH is a general mediator of cell death and uses nuclear translocation as a signaling mechanism. 相似文献
55.
Brian A. McGovern M.D. Hasan Garan M.D. Jeremy N. Buskin M.D. 《Current problems in cardiology》1988,13(12):790-859
Within the past 20 years, our knowledge concerning the epidemiology, natural history, and treatment of VT has expanded greatly. A variety of effective pharmacologic, surgical and electrical therapies for VT are now available to the clinician. Patients who present with ventricular, tachyarrhythmias should undergo a comprehensive medical evaluation directed at identifying and treating such factors as ischemia, congestive heart failure, valvular heart disease, sensitivity to cardioactive drugs, and metabolic derangements. Many patients who present with asymptomatic ventricular arrhythmias do not require specific antiarrhythmic drug therapy. However, certain patients who have already suffered a life-threatening arrhythmia or who are at high risk for such arrhythmia should be vigorously treated with specific antiarrhythmic therapy guided for that individual patient. The efficacy of any antiarrhythmic treatment should be assessed by ECG monitoring, exercise testing, and/or electrophysiologic study. In the near future, potentially revolutionary new electrical therapies for ventricular tachyarrhythmias will be evaluated. It is to be hoped that these devices used in combination with pharmacologic and surgical therapies may dramatically reduce the incidence of sudden cardiac death in high-risk patients. 相似文献
56.
Computer-derived equations for predicting survival postoperatively. Their usefulness and limitations
E B Rypins F Khan D Collins-Irby I J Sarfeh J T Ashurst E A Stemmer 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(3):354-357
We used multivariate analysis to determine whether survival following perforations of the gastrointestinal tract could be accurately predicted from preoperative data. Of 12 variables tested, four were found to have predictive value. These were age, pulmonary disease, preoperative shock, and the attending surgeon. When these four variables were employed in a logistic regression equation on 42 patients, it correctly predicted which 21 patients died before leaving the hospital. To produce an equation useful for other hospitals, we recalculated it without the attending surgeon variable. Again, the equation was used to predict survival. The correlation of predicted vs observed outcome remained high, and, using a 2 x 2 chi 2 test, the correlation was significant. We then cross validated the three-variable model on data from a second hospital. The model accurately predicted the new data equally well. We believe that predictive models can identify risk factors in a variety of patient populations and can determine who is likely to benefit from specific treatment modalities. 相似文献
57.
Gall bladder hydatid cyst is a rare entity. Concurrent occurrence of gall blader hydatid cysts along with liver cysts, especially with the biliary channels clear of cysts, is very rare. We report a 27-year-old man with a gall bladder hydatid cyst that was diagnosed only after opening the resected specimen of the gall bladder. 相似文献
58.
A single dose of activated charcoal (10 g) significantly reduced the half-life of elimination (1.02 +/- 0.10 and 0.70 +/- 0.04 h for the control and treated groups, respectively) and mean residence time (1.01 +/- 0.12 and 0.76 +/- 0.05 h for the control and treated groups, respectively) of morphine in rabbits. A 40% increase in the systemic clearance (85.73 +/- 7.72 and 122.64 +/- 16.32 mL min-1 kg-1 for the control and treated groups, respectively) and a 30% decrease in AUC (204.38 +/- 22.20 and 140.03 +/- 19.32 micrograms h L-1 in the control and treated groups, respectively) were also noted. Charcoal administration did not significantly alter the volume of distribution (Varea and Vss) or the apparent distribution half-life. A two-compartment model adequately described morphine kinetics in control and treated rabbits; charcoal administration produced a significant increase in the tissue compartment rate constant (K21). This finding indicates that activated charcoal not only enhances the systemic elimination of morphine, but also accelerates the rate of transfer of morphine from the tissue compartment to the central compartment. 相似文献
59.
Jamal M. Arif Sikandar G. Khan Mohammad Aslam Nayyara Mahmood Qamar Rahman 《Basic & clinical pharmacology & toxicology》1992,71(1):37-40
Abstract: In order to determine the pulmonary toxicity of kerosene and its ignition product (soot) in asbestos exposed subjects, the activities of phase I and phase II drug metabolizing enzymes in rat lungs after single intratracheal coexposure to Indian chrysotile asbestos and kerosene or its soot and Indian chrysotile were assayed. Exposure to kerosene or its soot resulted in a significant increase in the level of microsomal cytochrome P-450 and the activity of P-450 dependent monooxygenase, benzo(a)pyrene hydroxylase, as well as in the activities of microsomal epoxide hydrase and cytosolic glutathione-S-transferase (GST). However, in chrysotile exposed animals a reverse pattern in these parameters was recorded. The co-exposure to chrysotile and kerosene or chrysotile and soot led to a significant depletion in cytochrome P-450 level and a decrease in the activities of benzo(a)pyrene hydroxylase, epoxide hydrase and GST when compared to kerosene and soot controls, respectively. These results suggest that asbestos by altering the pulmonary drug metabolizing enzyme system may increase the toxic potential of kerosene and its ignition product in the respiratory system. 相似文献
60.
We describe 100 consecutive patients with histologically proven gastric carcinoma who were admitted to various hospitals in Northern Pakistan. Twenty-six per cent of patients were under 40 years of age. In a majority of patients the tumour was of a morphological type associated with poor prognosis. In most cases the disease was already at an advanced stage at the time of diagnosis, and most patients died within one year. 相似文献