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71.
<正>Organophosphorus pesticides(OPs)are extensively used for their high efficiency,broad spectrum,and low residue.However,the health hazards caused by long-term, low-dose exposure to OPs are easily ignored. Omethoate is a large class of OPs that is widely used in China. The inhibition of the cholinesterase(ChE)activity is the main toxicity mechanism of OPs, and such an activity is used as a biomarker of exposure to OPs[1].  相似文献   
72.
Objective To determine if ARHGEF10 has a haploinsufficient effect and provide evidence to evaluate the severity,if any,during prenatal consultation.Methods Zebrafish was used as a model for generating mutant.The pattern of arhgef10 expression in the early stages of zebrafish development was observed using whole-mount in situ hybridization(WISH).CRISPR/Cas9 was applied to generate a zebrafish model with a single-copy or homozygous arhgef10 deletion.Activity and light/dark tests were performed in arhgef10?/?,arhgef10+/?,and wild-type zebrafish larvae.ARHGEF10 was knocked down using small interferon RNA(siRNA)in the SH-SY5Y cell line,and cell proliferation and apoptosis were determined using the CCK-8 assay and Annexin V/PI staining,respectively.Results WISH showed that during zebrafish embryonic development arhgef10 was expressed in the midbrain and hindbrain at 36-72 h post-fertilization(hpf)and in the hemopoietic system at 36-48 hpf.The zebrafish larvae with single-copy and homozygous arhgef10 deletions had lower exercise capacity and poorer responses to environmental changes compared to wild-type zebrafish larvae.Moreover,arhgef10?/? zebrafish had more severe symptoms than arhgef10+/- zebrafish.Knockdown of ARHGEF10 in human neuroblastoma cells led to decreased cell proliferation and increased cell apoptosis.Conclusion Based on our findings,ARHGEF10 appeared to have a haploinsufficiency effect.  相似文献   
73.
A group of 31 rabies viruses (RABVs), recovered primarily from dogs, one deer and one human case, were collected from various areas in China between 1989 and 2006. Complete G gene sequences determined for these isolates indicated identities of nucleotide and amino acid sequences of >or=87% and 93.8%, respectively. Phylogenetic analysis of these and some additional Chinese isolates clearly supported the placement of all Chinese viruses in Lyssavirus genotype 1 and divided all Chinese isolates between four distinct groups (I-IV). Several variants identified within the most commonly encountered group I were distributed according to their geographical origins. A comparison of representative Chinese viruses with other isolates retrieved world-wide indicated a close evolutionary relationship between China group I and II viruses and those of Indonesia while China group III viruses formed an outlying branch to variants from Malaysia and Thailand. China group IV viruses were closely related to several vaccine strains. The predicted glycoprotein sequences of these RABVs variants are presented and discussed with respect to the utility of the anti-rabies biologicals currently employed in China.  相似文献   
74.
The effects of medical grade polycaprolactone-tricalcium phosphate (mPCL-TCP) (80:20) scaffolds on primary human alveolar osteoblasts (AOs) were compared with standard tissue-culture plates. Of the seeded AOs, 70% adhered to and proliferated on the scaffold surface and within open and interconnected pores; they formed multi-layered sheets and collagen fibers with uniform distribution within 28 days. Elevation of alkaline phosphatase activity occurred in scaffold-cell constructs independent of osteogenic induction. AO proliferation rate increased and significant decrease in calcium concentration of the medium for both scaffolds and plates under induction conditions were seen. mPCL-TCP scaffolds significantly influenced the AO expression pattern of osterix and osteocalcin (OCN). Osteogenic induction down-regulated OCN at both RNA and protein level on scaffolds (3D) by day 7, and up-regulated OCN in cell-culture plates (2D) by day 14, but OCN levels on scaffolds were higher than on cell-culture plates. Immunocytochemical signals for type I collagen, osteopontin and osteocalcin were detected at the outer parts of scaffold-cell constructs. More mineral nodules were found in induced than in non-induced constructs. Only induced 2D cultures showed nodule formation. mPCL-TCP scaffolds appear to stimulate osteogenesis in vitro by activating a cellular response in AO's to form mineralized tissue. There is a fundamental difference between culturing AOs on 2D and 3D environments that should be considered when studying osteogenesis in vitro.  相似文献   
75.
This study investigated the effect of a crown-lengthening ferrule on the fracture resistance of endodontically-treated teeth restored with two dowel-core systems. Thirty-two extracted mandibular first premolars were sectioned perpendicular to the long axis at a point 1.0 mm occlusal to the buccal cementoenamel junction. Following endodontic treatment, the teeth were randomly assigned to four groups: cast Ni-Cr alloy dowel-core with no ferrule (Group A1), cast Ni-Cr alloy dowel-core with 2.0 mm ferrule (Group A2), prefabricated carbon fiber-reinforced dowel-resin core with no ferrule (Group B1) and carbon fiber-reinforced dowel-resin core with 2.0 mm ferrule (Group B2). Each specimen was embedded in a self-cured acrylic resin block from 2.0 mm apical to the margins of a cast Ni-Cr alloy crown, then loaded at 150 degrees from the long axis in a universal testing machine at a crosshead speed of 1.0 mm/minute until fracture. The data were recorded and analyzed using ANOVA and Fisher's exact tests, with alpha = 0.05. Mean failure loads (kN) for the A1, A2, B1 and B2 Groups were: 1.46 (S.D. 0.45), 1.07 (0.21), 1.13 (0.30) and 1.02 (0.27). The teeth restored with cast Ni-Cr dowel-cores and 2.0 mm ferrules demonstrated significantly lower fracture strengths, p = 0.04. There were significant differences in the root fracture patterns between the two dowel systems, with the carbon fiber-reinforced dowel-resin core system, being the less severe p < 0.05. Crown lengthening with a 2.0 mm apical extended ferrule resulted in reduced fracture strengths for endodontically-treated teeth restored using two dowel-core systems and cast metal crowns. The carbon fiber-reinforced dowel-resin core system reduced the severity of the root fractures.  相似文献   
76.
背景:研究表明,转化生长因子β1被应用于周围神经移植来抑制或减弱移植排斥反应,但在某些情况下,转化生长因子又表现出正向免疫调节作用。所以有必要进行量效关系研究获取可靠的数据佐证。 目的:从剂量学上观察局部注射转化生长因子β1质粒与免疫排斥反应的量效关系。 设计、时间及地点:随机对照动物实验,于2007—06/2008-04在哈尔滨医科大学动物实验中心完成。 材料:选用雄性Wistar大鼠20只为供体。清洁级雄性SD大鼠50只为受体,随机分为5组,每组10只:自体神经移植组、空质粒异体神经移植组、低、中、高剂量转化生长因子β1质粒异体神经移植组。pAdTrack—CMV—TGF-β1质粒,pAdEasy—1—Bj51833细胞由华中科技大学同济医学院附属协和医院传染病实验室曾令兰教授惠赠。 方法:于手术显微镜下,从犁状肌下孔0.5cm处整齐剪下长约1cm的坐骨神经,将供体神经桥接于神经缺损处,异体神经移植组转化生长因子β1质粒注射剂量为10,20,40μg/只,空质粒异体神经移植组注射空质粒。 主要观察指标:术后6周进行运动神经传导速度、病理学、混合淋巴细胞培养和轴突计数检查。 结果:高剂量转化生长因子β1质粒异体神经移植组运动神经传导速度、轴突计数与自体神经移植组接近(P〉0.05),并优于低剂量转化生长因子β1质粒异体神经移植组(P〈0.05)。病理学及透射电镜显示,高剂量转化生长因子β1质粒异体神经移植组移植神经段效果接近于新鲜自体神经移植组(P〉0.05),并优于低剂量转化生长因子β1质粒异体神经移植组。高剂量转化生长因子β1质粒异体神经移植组混合淋巴细胞培养、迟发性超敏反应优于低剂量转化生长因子β1质粒异体神经移植组(P〈0.05)。 结论:局部注射转化生长因子β1质粒减轻大鼠同种异体坐骨神经移植后免疫排斥反应的作用,在10~40μg范围内,随剂量的增加而增强。  相似文献   
77.
Dysphagia in patients with brainstem stroke: incidence and outcome   总被引:13,自引:0,他引:13  
OBJECTIVE: This study was conducted to delineate the incidence and outcome of dysphagia among hospitalized patients who were referred for rehabilitation because of brainstem stroke. DESIGN: We retrospectively reviewed the medical records of 36 patients who were admitted because of brainstem stroke. Information on the patients' clinical features, feeding status, and the results of clinical and videofluoroscopic swallowing examinations were obtained through chart review. Follow-up interviews were conducted via telephone to learn the general medical condition and feeding status of the patients 7-43 mo after hospital discharge. RESULTS: A total of 81% of the patients had dysphagia at the time of initial clinical swallowing evaluation, which was performed 10-75 days after the onset of stroke. A total of 79% of the dysphagic individuals depended on tube feeding at the initial evaluation; 22% of all individuals could not resume oral intake at discharge. Statistical analyses revealed a significant association between poor outcome and disease involving the medulla, the presence of a wet voice during the initial swallowing test, and a delay or absence of the swallowing reflex. The incidence of aspiration pneumonia was 11%. There was a correlation between the detection of aspiration by modified barium meal videofluoroscopy and the development of aspiration pneumonia. Follow-up interviews showed that 88% of the 27 patients who were contacted had resumed full oral intake 4 mo after the onset of stroke. CONCLUSIONS: The incidence of dysphagia was relatively high in our study population. The long-term outcome was favorable.  相似文献   
78.
目的观察血卟啉单甲醚声动力疗法对兔耳增生性瘢痕(hyperplastic scar,HS)的疗效。方法成年大耳白兔60只,随机分成5组。在声动力治疗第2、4、6、8周分别切取两组瘢痕组织,进行指标检测。结果治疗组可降低成纤维细胞密度、瘢痕增生指数,与模型对照组比较差异有统计学意义(P〈O.05),可降低胶原纤维的面密度,从上皮化后第4周开始与模型组比较差异有统计学意义(P〈O.01)。结论声动力效应能够显著降低兔耳HS,可望为HS治疗提供新的手段。  相似文献   
79.
The uptake of the sulfated bile acid sulfolithocholyltaurine (SLCT) was investigated in isolated rat hepatocytes and in HeLa cells transfected with complementary DNAs (cDNAs) of organic anion transporting polypeptides (Oatps) 1 and 2 cloned from rat liver. In hepatocytes, transport of SLCT was greatly reduced by bromosulfophthalein (BSP), estrone sulfate, the precursor bile acids cholyltaurine and lithocholyltaurine, and 4,4'-diisothiocyanostilbene-2-2'-disulfonic acid (DIDS). However, SLCT transport was insensitive to 4-methylumbelliferyl sulfate, harmol sulfate, digoxin, fexofenadine, and lack of sodium ion. Because the estimation of kinetic constants was enhanced with use of inhibitors, BSP (1-50 micromol/L) was added to isolated rat hepatocytes to assess the various transport components for SLCT uptake. The resulting data showed a nonsaturable pathway and at least 2 pathways of different Michaelis-Menten constants (K(m)) (70 and 6 micromol/L) and similar maximum velocities (V(max)) (1.73 and 1.2 nmol/min/mg protein) and inhibition constants of 0.63 and 10.3 micromol/L for BSP. In expression systems, SLCT was taken up by Oatp1 and Oatp2 expressed in HeLa cells with similar K(m) values (12.6 +/- 6.2 and 14.6 +/- 1.9 micromol/L). These K(m) values were comparable to that observed for the high-affinity pathway in rat hepatocytes. In conclusion, the results suggest that transport of SLCT into rat liver is mediated in part by Oatp1 and Oatp2, high-affinity pathways, a lower-affinity pathway of unknown origin, and a nonsaturable pathway that is compatible with a transport system of high K(m) and/or passive diffusion.  相似文献   
80.
ABM: To study the expression of interferon-alpha/beta (IFN-α/β) receptor protein in liver of patients with hepatitis C virus (HCV)-related chronic liver disease and its clinical significance. METHODS: A total of 181 patients with HCV-related chronic liver disease included 56 with HCV-related liver cirrhosis (LC) and 125 with chronic hepatitis C (CHC). CHC patients were treated with five megaunits of interferon-α1b six times weekly for the first 2 weeks and then every other day for 22 wk. The patients were divided into interferon (IFN) treatment-responsive and non-responsive groups, but 36 patients lost follow-up shortly after receiving the treatment. The expression of IFN-α/β receptor (IFN-α/βR) protein in liver of all patients was determined with immunofluorescence. RESULTS: In liver of patients with HCV-related chronic liver disease, the expression of IFN-α/βR protein in liver cell membrane was stronger than that in cytoplasm and more obvious in the surroundings of portal vein than in the surroundings of central vein. Moreover, it was poorly distributed in hepatic lobules. The weak positive, positive and strong positive expression of IFN-α/βR were 40% (50/125), 28% (35/125), 32% (40/125), respectively in CHC group, and 91.1% (51/56), 5.35% (3/56), and 3.56% (2/56), respectively in LC group. The positive and strong positive rates were higher in CHC group than in LC group (P<0.01). In IFN treatment responsive group, 27.8% (10/36) showed weak positive expression; 72.2% (26/36) showed positive or strong positive expression. In the non-responsive group, 71.7% (38/53) showed weak positive expression; 28.3% (15/53) showed positive or strong positive expression. The expression of IFN-α/βR protein in liver was more obvious in IFN treatment responsive group than in non-responsive group. CONCLUSION: Expression of IFN-α/βR protein in liver of patients with HCV-related chronic liver disease is likely involved in the response to IFN treatment.  相似文献   
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