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The sensitive ELISA assay was used to measure the specific rubella virus IgG & IgM, and also the total IgM in the umbilical cord sera taken from 182 Saudi mothers during delivery in the Maternity Department at Al Ali General Hospital, Riyadh, Saudi Arabia. Nearly 84.6% (154 out of 182) Saudi women tested were found to be immune to rubella virus.  相似文献   
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Cardiac attacks and sudden cardiac deaths are more common in cold seasons. Up to now the underlying pathophysiologic mechanism of the seasonal variation in cardiovascular accidents is scarcely known. There are many physiological mechanisms which exhibit seasonal variation (e.g. blood pressure). Nitric oxide (NO) is a potent vasodilator, and impaired responsiveness to its physiological effects has been reported in many pathological situations including cardiovascular accidents. The aim of the present study was to evaluate the role of NO-dependent mechanisms on seasonal variation in aortic relaxation in vitro in rats. Male Sprague-Dawley rats grown up in different seasons in natural light/dark situation were used in the study, while the temperature and humidity were kept constant throughout the study (22+/-1 degrees C). The in vitro aortic ring responsiveness to an NO donor was studied in different seasons. Intact and denuded rings were pre-contracted with phenylephrine and vaso-relaxatory response to sodium isosorbide dinitrate (10(-8) to 10(-4)M) was recorded in vitro. The vaso-relaxatory response to isosorbide dinitrate (10(-6)M) was higher in aortic rings obtained in summer compared with those in winter and fall. There was a significant difference in EC(50) of sodium isosorbide dinitrate-induced vaso-relaxation of rings obtained from rats which were grown up in summer and winter (EC(50): 2.23+/-0.069 versus 4.31+/-0.088, P<0.05). The maximum response (R(max)) to isosorbide dinitrate was, however, identical in rings obtained from these rats. In conclusion, the in vitro responsiveness of aorta to NO is affected by seasonal light/dark periods the rats are exposed. This might be one of the reasons why more sudden cardiac deaths occur also in humans during winter.  相似文献   
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BACKGROUND: The STAN methodology has been shown to reduce both operative delivery for fetal distress and the cord artery metabolic acidosis rate. OBJECTIVE: The objective of this study was to monitor delivery modes and perinatal outcomes following the introduction of the STAN methodology and the evolution of its use at our institution. METHODS: Two periods were characterized: June 2000-June 2002 (period 1) and July 2002-April 2005 (period 2). Parity, mode of labor and delivery, ST events, and neonatal outcome (Apgar score and pH of the umbilical cord artery and vein), cases of metabolic acidosis and operative delivery for fetal distress were studied. RESULTS: One thousand eight hundred and eighty-nine women were included in the study. The rate of use of STAN increased from 13.5% to 16% over these two time periods. The rate of metabolic acidosis was low: 0.28% and 0.45%, respectively. No cases of neonatal encephalopathy or of perinatal death were diagnosed. There was a decrease in the rate of operative delivery for fetal distress (163/701 (22.9%) vs. 228/1111 (20.3%), p = 0.26). CONCLUSIONS: According to the literature, our use of the STAN appears to be very successful; the metabolic acidosis rate was 0.38% and the rate of operative delivery for fetal distress decreased. We improved the accuracy of the interpretation of the fetal heart rate.  相似文献   
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Mutation analysis in the family of a child with 21-hydroxylase deficiency showed that the father and affected child were homozygous for a mutation, A/C655G, believed to activate a cryptic splice site in intron 2 of the 21-hydroxylase gene. The father, who was clinically asymptomatic, showed no biochemical evidence of disease. These results create problems for the management of future pregnancies in such families and for the interpretation of the risk associated with carrier status for this mutation.  相似文献   
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We report that gp49B1, a mast cell membrane receptor with two immunoreceptor tyrosine-based inhibitory motifs (ITIM), constitutively inhibits mast cell activation-secretion induced by stem cell factor (SCF), a tissue-derived cytokine that also regulates mast cell development. The intradermal injection of SCF into the ears of gp49B1 null (gp49B(-/-)) mice elicited approximately 4- and 2.5-fold more degranulating mast cells and tissue swelling caused by edema, respectively, than in gp49B(+/+) mice. SCF did not induce tissue swelling in mast cell-deficient mice, and the responsiveness of gp49B(-/-) mice to mast cell-associated amine and lipid mediators was unaltered. When gp49B(+/+) and gp49B(-/-) mice were pretreated with antagonists of the amines, SCF-induced tissue swelling was reduced by >90% and 60%, respectively, and it was reduced by >90% in both genotypes when a cysteinyl leukotriene receptor antagonist was also provided. Hence, the dominant contribution of secretory granule amines to SCF-induced tissue swelling is the result of gp49B1-mediated inhibition of the production of cysteinyl leukotrienes by mast cells. Our findings also provide the first example of an ITIM-bearing receptor that constitutively suppresses inflammation generated in vivo independently of the adaptive immune response by a receptor that signals through intrinsic tyrosine kinase activity rather than immunoreceptor tyrosine-based activation motifs.  相似文献   
7.
OBJECTIVE: To evaluate the relationship between the serum concentration of TNFalphaRII and some adhesion molecules (including ICAM-1, VCAM-1, P-selectin and E-selectin) and coronary artery stenosis. DESIGN AND SETTING: Observational (cross-sectional) study in a university heart hospital in Tehran, Iran. PATIENTS: 81 patients with angiographically proven coronary artery disease were compared with 75 individuals who had undergone coronary angiography with no significant evidence of stenosis (control subjects). METHODS: Soluble adhesion molecules and TNFalphaRII were determined by enzyme-linked immunosorbent assay technique. sICAM-1 and sP-selectin values were significantly higher in patients with coronary artery disease than in control subjects (146 +/- 38 vs. 132 +/- 48 p < 0.04 and 275 +/- 107 vs. 241 +/- 104 ng/ml p < 0.04 respectively). Multiple logistic regression analysis showed sICAM-1 as an independent discriminating risk factor for coronary artery disease (p < 0.03). Prediction models that incorporated sICAM-1 in addition to other established coronary risk factors were significantly better at predicting risk than the models based on the other risk factors alone. Multiple regression analysis indicated that sP-selectin levels were greater in patients with single-vessel disease than in the respective normal (p < 0.01). CONCLUSIONS: Our findings suggest that sICAM-1 has an association with stable coronary artery disease and the evaluation of this marker may improve the coronary risk assessment in Iranian patients.  相似文献   
8.
A reversed-phase high-performance liquid chromatography method is described for the determination of oxybutynin (OXB) in human bladder samples. Following homogenization, tissue samples underwent double extraction with hexane and eventually were concentrated by freeze-drying before analysis. Chromatographic separation was performed with a mobile phase of acetonitrile-water-1 M ammonium acetate, pH 7.0 (85:13:2, v/v/v) at a flow-rate of 0.5 ml/min and double (electrochemical and UV) detection was applied. The retention time of oxybutynin eluting peak was around 18 min. Using a standard curve range of 10 to 500 ng/ml the quantification limit with electrochemical detection was 5 ng/ml with an injection volume of 100 microl. Within-day and day-to-day relative standard deviation values were 4.9 and 9.81%, respectively, while a 94% accuracy and a 72% recovery was attained. We applied this method to compare the OXB levels into bladder wall tissue samples after passive diffusion and after electromotive drug administration (EMDA), using a two-chambered poly(vinyl chloride) diffusion cell designed and developed in our laboratory. The results obtained show that EMDA enhanced OXB penetration into bladder wall and that this novel way of local drug administration can be potentially used in patients with neurogenic bladder dysfunction or urinary incontinence.  相似文献   
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