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The purpose of this study is to investigate the relationship between the blood level of cadmium and the occurrence of ectopic pregnancy. Forty-one (41) case patients with ectopic pregnancy and 41 uncomplicated intrauterine pregnant patients as controls were recruited. The concentrations of cadmium (Cd) were measured from blood samples using atomic absorption spectrometry. The cases and controls were similar in age, body mass index, and smoking habits. The median blood level of Cd was 0.32 μg/l (interquartile range [IQR] 0.00–0.71) in the women with ectopic pregnancies and 0.34 μg/l (IQR 0.09–0.59) in the controls. There was no significant association between blood cadmium levels and ectopic pregnancy.  相似文献   
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In a survey of starch-based foods sampled from retail outlets in Malaysia, fungal colonies were mostly detected in wheat flour (100%), followed by rice flour (74%), glutinous rice grains (72%), ordinary rice grains (60%), glutinous rice flour (48%) and corn flour (26%). All positive samples of ordinary rice and glutinous rice grains had total fungal counts below 103 cfu/g sample, while among the positive rice flour, glutinous rice flour and corn flour samples, the highest total fungal count was more than 103 but less than 104 cfu/g sample respectively. However, in wheat flour samples total fungal count ranged from 102 cfu/g sample to slightly more than 104 cfu/g sample. Aflatoxigenic colonies were mostly detected in wheat flour (20%), followed by ordinary rice grains (4%), glutinous rice grains (4%) and glutinous rice flour (2%). No aflatoxigenic colonies were isolated from rice flour and corn flour samples. Screening of aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 using reversed-phase HPLC were carried out on 84 samples of ordinary rice grains and 83 samples of wheat flour. Two point four percent (2.4%) of ordinary rice grains were positive for aflatoxin G1 and 3.6% were positive for aflatoxin G2. All the positive samples were collected from private homes at concentrations ranging from 3.69–77.50 μg/kg. One point two percent (1.2%) of wheat flour samples were positive for aflatoxin B1 at a concentration of 25.62 μ};g/kg, 4.8% were positive for aflatoxin B2 at concentrations ranging from 11.25–252.50 μg/kg, 3.6% were positive for aflatoxin G1 at concentrations ranging from 25.00–289.38 μg/kg and 13.25% were positive for aflatoxin G2 at concentrations ranging from 16.25–436.25 μg/kg. Similarly, positive wheat flour samples were mostly collected from private homes. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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Developmental dysplasia of the hip (DDH) is a congenital condition characterized by abnormality in acetabulum size and/or shape. The incidence rate of DDH differs between different populations with risk factors including positive family history, breech presentation, sex, firstborn status, side of the hip, mode of delivery and oligohydramnios. It is recognized that DDH has a genetic component that exhibit autosomal dominant patterns. Many candidate genes have been studied and found to be associated with the disease; most of them are normally involved in cartilage development and joint metabolism. In this study, the association of four single-nucleotide polymorphisms (SNPs) (rs731236, rs1544410, rs7975232 and rs2228570) in the vitamin D receptor (VDR) gene was studied by a case–control analysis. The study sample involves 50 cases with confirmed DDH presentation and 50 nonDDH controls. SNPs were genotyped using conventional polymerase chain reaction (PCR) and restriction fragment-length polymorphism (RFLP) techniques. Genotype and allele frequencies were analysed using SPSS software. No significant associations were found between the VDR polymorphisms analysed and DDH. Further work need to be performed using genomewide analysis to elucidate the genetic basis of DDH.  相似文献   
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This work addresses the kinetic analysis of the interaction of tacrine with bovine retina acetylcholinesterase (AChE, E.C. 3.1.1.7). It was found that the tacrine effect was reversible in nature. Tacrine inhibited bovine retinal AChE activity in a concentration-dependent manner; IC50 was found to be 8.07 nM. The Michaelis-Menten constant (Ka) for the hydrolysis of acetylthiocholine iodide (ASCh) by AChE was 0.061 mM in the control system, and this value was increased by 54–67% in the tacrine-treated systems. The Vmax was 0.701 μ mole/min per milligram protein for the control system, but it was decreased by 26–69% in the tacrine-treated systems. The Lineweaver–Burk plot, Dixon plot, and their secondary replots indicated that the nature of the inhibition was of the partial mixed type, that is, a mixture of competitive and noncompetitive inhibition. The values of Ki and Kt were estimated to be as 4.475 and 8.517 nM, respectively. © 1998 John Wiley & Sons, Inc. J Biochem Toxicol 12: 245–251, 1998  相似文献   
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