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71.
目的:探讨中国广东籍汉族人细胞色素P4502E1基因5′侧翼区的多态性分布规律。方法:利用聚合酶链反应和RsaⅠ、PstⅠ限制性片段长度多态性(PCRRFLP)技术对82名正常中国广东籍汉族人的细胞色素P4502E1基因5′侧翼区的多态性进行了检测。结果:82名正常中国广东籍汉族人的细胞色素P4502E1基因5′侧翼区C1(RsaⅠ+,PstⅠ)、C2(RsaⅠ,PstⅠ+)等位基因频率分别为0854,0146;基因型C1C1、C1C2、C2C2的比率分别为0732、0244、0024,符合HardyWeinberg平衡分布。结论:中国广东籍汉族人细胞色素P4502E1基因5′侧翼区RsaⅠ和PstⅠ多态性分布规律与欧美人显著不同。  相似文献   
72.
目的:探究二叶式主动脉瓣中miRNA-195调控瓣膜钙化的可能机制。方法:收集35例接受主动脉瓣置换术患者狭窄的二叶式或三叶式主动脉瓣,通过PCR及Western blot分别检测miRNA-195的表达量、果蝇母源抗皮肤生长因子(drosophila mothers against decapentaplegic 7,SMAD7)的mRNA及蛋白表达量。双荧光素酶法预测miRNA-195的靶基因。在猪瓣膜间质细胞中分别沉默和过表达miRNA-195,检测SMAD7的mRNA表达水平并探究两者的相互关系。在人类瓣膜组织上通过免疫组化染色检测基质金属蛋白酶(matrix metalloproteinase,MMP)-2、MMP-9蛋白水平,通过天狼星红染色检测胶原蛋白水平,通过Von Kossa染色比较钙化程度差异,进而研究钙化相关的功能改变。结果:与狭窄的三叶式主动脉瓣相比,狭窄的二叶式主动脉瓣中miRNA-195表达降低,SMAD7的mRNA和蛋白水平升高。双荧光素酶实验提示SMAD7是miRNA-195的直接靶标。在猪瓣膜间质细胞中沉默miRNA-195引起SMAD7 mRNA水平升高,过表达miRNA-195引起SMAD7 mRNA水平降低。狭窄钙化的二叶式主动脉瓣组织中MMP-2、MMP-9及胶原的表达较狭窄钙化的三叶式主动脉瓣升高。结论:在二叶式主动脉瓣中,下调的miRNA-195促进了SMAD7表达,进而促进细胞外基质的纤维化并最终促进其钙化。  相似文献   
73.
Spinel oxides (AB2O4) have been widely studied as catalysts for methane combustion. Increasing attention was focused on the catalysis properties of the [B2O3] octahedron; however, the role of the [AO] tetrahedron in the catalytic activity was seldom discussed. Herein, a series of (CuO)x–CuCo2O4 (x = 0, 0.1, 0.2) composite oxides were synthesized by a solvothermal method. The structure, morphology, and physicochemical properties of the as-synthesized samples were characterized by the XRD, SEM, BET, and XPS techniques. The results of the catalytic activity tests showed that the coexistence of CuO with CuCo2O4 can improve the catalytic activity. The XPS results demonstrated that there were remarkable Cu+ ions present in the composite oxides, which can cause increases in the number of oxygen vacancies on the surface of the catalysts. In addition, the redox of Cu+ and Cu2+ may improve the oxygen exchange capacity for methane oxidation.

CuO and CuCo2O4 exhibit a synergistic effect in catalyzing methane combustion, which increases the oxidation rate of methane on the surface of (CuO)0.2–CuCo2O4 composite oxide and decreasing the methane combustion temperature.  相似文献   
74.
75.
A new amdoparvovirus, named raccoon dog and fox amdoparvovirus (RFAV), was identified in farmed sick raccoon dogs and arctic foxes. Phylogenetic analyses showed that RFAV belongs to a new species within the genus Amdoparvovirus of the family Parvoviridae. An RFAV strain was isolated in Crandell feline kidney cell culture.  相似文献   
76.
BackgroundRadical nephroureterectomy (RNU) is the principal method for treatment of high-risk upper urinary tract urothelial carcinoma (UTUC). The transperitoneal approach is associated with poor disease progression, but the distal ureter-bladder cuff (DUBC) resection through retroperitoneal laparoscopic approach is difficult. This study proposed a modulated RNU technique, namely, total retroperitoneal laparoscopic radical nephroureterectomy (tRLRNU), with its advantages of DUBC resection and requiring fewer trocars etc. The efficiency, safety, and short-term impacts were retrospectively compared with total transperitoneal laparoscopic radical nephroureterectomy (tTLRNU).MethodsTotal of 12 patients who received tRLRNU and 28 patients who received tTLRNU were enrolled. The choice of surgical approach was random and their data were retrospectively analyzed. During tRLRNU, the laparoscope was versed towards the caudal direction and a retroperitoneal laparoscopic ureterectomy was performed. The bladder cuff was entirely transected and the bladder incision was sutured. The tRLRNU cases were compared with the tTLRNU cases in terms of general clinical data, pathologic parameters, peri-operative parameters, adjuvant therapy, and short-term outcomes. The independent samples t-tests, chi-square tests, and Fischer exact tests were used to analyze the differences.ResultsThere were no significant differences in the basic patient characteristics between the 2 groups. The data were comparable. There were significantly fewer trocars utilized in tRLRNU group compared to tTLRNU group (P=0.0008). tRLRNU group experienced less blood loss (98.33±61.32 versus 170.71±121.32 mL; P=0.017), smaller drainage volume (182.08±163.60 versus 1,924.82±3,370.02 mL; P=0.011), and shorter extubation time (5.67±1.07 versus 8.57±6.96 days; P=0.040) compared to tRLRNU group. There were no statistically differences in the other peri-operative parameters, including whole operation time, transfusion, visceral and vascular injuries, open conversion, post-operative bleeding, recovery time of intestinal function, and discharge time. The patient outcomes in tTLRNU group at 6 months were significantly worse than that of tRLRNU group by comparing progression-free survival, progression survival and mortality (P=0.039).ConclusionsThe tRLRNU was potentially safer, minimally invasive, and more effective compared to the tTLRNU. Due to the small sample size, short follow-up time and no randomization of the study, future comparative studies are warranted to further analyze long-term outcomes of tRLRNU.  相似文献   
77.
目的探讨肿瘤相关基因Twist表达在大肠癌临床病理诊断中的应用价值。方法应用鼠抗人Twist单克隆抗体采用S-P免疫组织化学方法检测112例不同类型大肠癌组织及40例正常肠粘膜组织中Twist的表达并与临床病理指标比较。结果在112例大肠癌组织中,Twist基因阳性表达78例;在正常组织中其阳性表达为15例,两者比较具有显著统计学差异(χ2=11.21,p=0.001);进一步综合临床病理资料统计分析,Twist在大肠癌组织中表达与肿瘤的分化程度、肿瘤浸润、淋巴结转移、Duke’s分期有关(p值分别为0.008、0.017、0.044、0.011),均有显著差异;而与病人年龄、性别无关(p值为0.286、0.887)。结论Twist基因表达检测能较好的判断大肠癌肿瘤分化程度、浸润、淋巴结转移等,在大肠癌诊断中作用明确,对临床病理学诊断有明确的指导作用。  相似文献   
78.
Three-dimensional (3D) imaging of the human retina is instrumental in vision science and ophthalmology. While interferometric retinal imaging is well established by optical coherence tomography (OCT), non-interferometric volumetric imaging in the human retina has been challenging up to date. Here, we report confocal oblique scanning laser ophthalmoscopy (CoSLO) to fill that void and harness non-interferometric optical contrast in 3D. CoSLO decouples the illumination and detection by utilizing oblique laser scanning and oblique imaging to achieve ∼4x better axial resolution than conventional SLO. By combining remote focusing, CoSLO permits the acquisition of depth signals in parallel and over a large field of view. Confocal gating is introduced by a linear sensor array to improve the contrast and resolution. For the first time, we reported non-interferometric 3D human retinal imaging with >20° viewing angle, and revealed detailed features in the inner, outer retina, and choroid. CoSLO shows potential to be another useful technique by offering 3D non-interferometric contrasts.  相似文献   
79.
We report a general protocol for <i>ortho</i>-C–H fluoroalkoxylation of benzaldehydes and benzylic amines utilizing an inexpensive amino amide as a transient directing group. In the presence of an electrophilic fluorinating bystanding oxidant and fluorinated alcohols, a wide range of benzaldehydes and benzylic amines could be oxygenated selectively at the ortho positions to afford fluoroalkyl aryl ethers. This elegant approach would provide appealing strategies for synthesis of drug molecules and natural products.

A general protocol for ortho-C–H fluoroalkoxylation of benzaldehydes and benzylic amines was exploited by utilizing an inexpensive amino amide as a transient directing group.  相似文献   
80.
Studies with relatively large sample size as well as long-term follow-up focusing on adult craniopharyngioma (CP) patients are still lacking. We attempted to identify independent prognostic factors and establish a nomogram model to estimate survival rates for adult CP patients.The Surveillance, Epidemiology, and End Results database was used to obtain data on patients with CP. Univariable and multivariable Cox analyses were utilized to identify the prognostic factors of adult CP patients. A survival prediction model was constructed and its predictive performance was also assessed.A total of 991 patients (695 in training group and 296 in validation group) were eligible for final inclusion. Multivariate Cox analysis presented that age at diagnosis, marital status, race, tumor size, and surgery type were statistically significant prognostic factors for overall survival (all P < .05). A graphical predicting nomogram model was developed to calculate the predicted patients’ survival probabilities at 1, 2, 5, and 10 years. The concordance indexes were 0.708 ± 0.019 and 0.750 ± 0.025 for the training and validation samples, respectively, demonstrating favorable discrimination abilities. Similarly, the time-dependent area under curve also showed overall satisfactory discrimination ability. Favorable consistencies between the predicted and actual survival were presented according to the calibration curves.An easy-to-use nomogram, being proven to be with reliable discrimination ability and accuracy, was established to help predict overall survival for adult patients with CP using the identified significant prognostic factors.  相似文献   
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