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851.
He YY Du GQ Cai B Yan Q Zhou L Chen XY Lu W Yang YX Wan XP 《Journal of cancer research and clinical oncology》2012,138(5):775-783
Purpose
The mechanisms underlying the effects of estrogen on endometrial cancer remain undefined. Although the classical mechanism of the action of estrogen involves binding to the estrogen receptors α and β, and transduction of the signal into the cell, G protein-coupled receptor (GPR) 30 has been shown to mediate nongenomic estrogen signaling. The goal of this study was to determine the role of GPR30 signal in the basic process such as invasion and carcinogenesis of endometrial cancer. 相似文献852.
Purpose
The P53–MDM2 pathway plays a central role in sarcoma pathogenesis. Functional P53 Arg72Pro and MDM2 T309G single-nucleotide polymorphisms (SNP) are considered to have significant effects on risk of sarcomas. 相似文献853.
Background/Aims: Selective inflow occlusion instead of portal triad clamping was used during laparoscopic left hemihepatectomy in our institution. This study observed its hemodynamic effects during operation. Methodology: Hemodynamic parameters including heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), mean pulmonary artery pressure (PAP), pulmonary capillary wedge pressure (PCWP), cardiac index (CI), systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR) were collected at 6 time points: after induction, after insufflation with CO2, after patient in reverse Trendelenburg position, after left branch of hepatic artery was occluded, after left branch of portal vein was occluded and after desufflation with patient supine. Results: No severe perioperative cardiopulmonary complications were observed. Occlusion of left branch of hepatic artery brought no significant hemodynamic change. Occlusion of left branch of portal vein increased CVP and CI and decreased SVR. CO2 inflation caused HR, MAP and SVR to increase. The change to reverse Trendelenburg position caused CVP and PAP to decrease. When placed in the supine position with deflation, MAP, CVP, PAP, PCWP and CI went to a higher than base level. HR and SVR returned to base level. Conclusions: Using selective inflow occlusion in laparoscopic left hemihepatectomy caused few hemodynamic changes before and after occlusion in patients without cardiopulmonary diseases. However, the change of position and inflation or deflation caused significant changes. 相似文献
854.
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856.
Aims: To evaluate the role of four‐dimensional (4D) ultrasound with B‐flow imaging and spatiotemporal image correlation (STIC) in the evaluation of normal fetal heart and congenital heart disease during pregnancy. Methods: Volume data sets of the fetal heart were acquired with automated transverse and longitudinal sweeps of the anterior chest wall. We studied 31 normal fetuses and 28 fetuses with congenital heart disease (6 with double‐outlet right ventricle, 5 with complete transposition of great arteries, 8 with tetralogy of Fallot, 3 with right aortic arch, 2 with persistent left superior vena cava, 3 with truncus arteriosus communis, and 1 with interruption of aortic arch) at gestation ages ranging from 18 to 39 weeks using transabdominal 4D B‐flow sonography with STIC (4D BF‐STIC). Results: Four‐dimensional BF‐STIC demonstrated dynamic angiographic features in both normal and abnormal fetal hearts. Four‐dimensional BF‐STIC images could not be obtained in two normal fetuses at 18.9 and 35.6 weeks because of the high fetal heart rate and inappropriate fetal position. Of the other 29 fetuses all extracardiac vessels such as aorta, pulmonary artery, ductus arteriosus, inferior vena cava, and ductus venosus could be detected on reconstructed images. In seven normal cases, a 4D image was recorded to allow simultaneous visualization of all four pulmonary veins. In the 28 fetuses with cardiac anomalies, 4D sonography with B‐flow imaging and STIC detected the “digital casts” of the outflow tracts, great arteries, and veins draining into the heart. These results demonstrate spatial relationship among these structures which provide important anatomical information. Conclusion: Four‐dimensional BF‐STIC provides a means of real time three‐dimensional evaluation of fetal extracardiac hemodynamics in the second and third trimesters. This novel technique assists in the evaluation of fetal cardiac hemodynamics and may play an important role in future fetal cardiac research and in the identification of anatomical features of different congenital cardiac anomalies. (Echocardiography 2012;29:614‐619) 相似文献
857.
Xiaodong Cai Libai Yang Jueqian Zhou Dan Zhu Qiang Guo Ziyi Chen Shuda Chen Liemin Zhou 《中国神经再生研究》2013,8(6):561-568
The Na+-K+-Cl-cotransporter 1 and K+-Cl-cotransporter 2 regulate the levels of intracellular chloride in hippocampal cells.Impaired chloride transport by these proteins is thought to be involved in the pathophysiological mechanisms of mesial temporal lobe epilepsy.Imbalance in the relative expression of these two proteins can lead to a collapse of Cl-homeostasis,resulting in a loss of gamma-aminobutyric acid-ergic inhibition and even epileptiform discharges.In this study,we investigated the expression of Na+-K+-Cl-cotransporter 1 and K+-Cl-cotransporter 2 in the sclerosed hippocampus of patients with mesial temporal lobe epilepsy,using western blot analysis and immunohistochemistry.Compared with the histologically normal hippocampus,the sclerosed hippocampus showed increased Na+-K+-Cl-cotransporter 1 expression and decreased K+-Cl-cotransporter 2 expression,especially in CA2 and the dentate gyrus.The change was more prominent for the Na+-K+-Cl-cotransporter 1 than for the K+-Cl-cotransporter 2.These experimental findings indicate that the balance between intracellular and extracellular chloride may be disturbed in hippocampal sclerosis,contributing to the hyperexcitability underlying epileptic seizures.Changes in Na+-K+-Cl-cotransporter 1 expression seems to be the main contributor.Our study may shed new light on possible therapies for patients with mesial temporal lobe epilepsy with hippocampal sclerosis. 相似文献
858.
Rui Cui Shiyuan Xu Liang Wang Hongyi Lei Qingxiang Cai Hongfei Zhang Dongmei Wang 《中国神经再生研究》2013,8(11):983-990
Extracts from rabbit skin inflamed by the vaccinia virus can relieve pain and promote repair of nerve injury. The present study intraperitoneally injected extracts from rabbit skin inflamed by the vaccinia virus for 3 and 4 days prior to and following intrathecal injection of bupivacaine into pregnant rats. The pain threshold test after bupivacaine injection showed that the maximum possible effect of tail-flick latency peaked 1 day after intrathecal injection of bupivacaine in the extract-pretreatment group, and gradually decreased, while the maximum possible effect in the bupivacaine group continued to increase after intrathecal injection of bupivacaine. Histological observation showed that after 4 days of intrathecal injection of bupivacaine, the number of shrunken, vacuolated, apoptotic and caspase-9-positive cells in the dorsal root ganglion in the extract-pretreatment group was significantly reduced compared with the bupivacaine group. These findings indicate that extracts from rabbit skin inflamed by the vaccinia virus can attenuate neurotoxicity induced by intrathecal injection of bupivacaine in pregnant rats, possibly by inhibiting caspase-9 protein expression and suppressing nerve cell apoptosis. 相似文献
859.
Christopher K. Egan Simon D.M. Jacques Marco Di Michiel Biao Cai Mathijs W. Zandbergen Peter D. Lee Andrew M. Beale Robert J. Cernik 《Acta biomaterialia》2013,9(9):8337-8345
The internal crystalline structure of a human molar tooth has been non-destructively imaged in cross-section using X-ray diffraction computed tomography. Diffraction signals from high-energy X-rays which have large attenuation lengths for hard biomaterials have been collected in a transmission geometry. Coupling this with a computed tomography data acquisition and mathematically reconstructing their spatial origins, diffraction patterns from every voxel within the tooth can be obtained. Using this method we have observed the spatial variations of some key material parameters including nanocrystallite size, organic content, lattice parameters, crystallographic preferred orientation and degree of orientation. We have also made a link between the spatial variations of the unit cell lattice parameters and the chemical make-up of the tooth. In addition, we have determined how the onset of tooth decay occurs through clear amorphization of the hydroxyapatite crystal, and we have been able to map the extent of decay within the tooth. The described method has strong prospects for non-destructive probing of mineralized biomaterials. 相似文献
860.
Bi-layer collagen/microporous electrospun nanofiber scaffold improves the osteochondral regeneration
Shufang Zhang Longkun Chen Yangzi Jiang Youzhi Cai Guowei Xu Tong Tong Wei Zhang Linlin Wang Junfeng Ji Peihua Shi Hong Wei Ouyang 《Acta biomaterialia》2013,9(7):7236-7247
An optimal scaffold is crucial for osteochondral regeneration. Collagen and electrospun nanofibers have been demonstrated to facilitate cartilage and bone regeneration, respectively. However, the effect of combining collagen and electrospun nanofibers on osteochondral regeneration has yet to be evaluated. Here, we report that the combination of collagen and electrospun poly-l-lactic acid nanofibers synergistically promotes osteochondral regeneration. We first fabricated bi-layer microporous scaffold with collagen and electrospun poly-l-lactic acid nanofibers (COL-nanofiber). Mesenchymal stem cells were cultured on the bi-layer scaffold and their adhesion, proliferation and differentiation were examined. Moreover, osteochondral defects were created in rabbits and implanted with COL-nanofiber scaffold. Cartilage and subchondral bone regeneration were evaluated at 6 and 12 weeks after surgery. Compared with COL scaffold, cells on COL-nanofiber scaffold exhibited more robust osteogenic differentiation, indicated by higher expression levels of OCN and runx2 genes as well as the accumulation of calcium nodules. Furthermore, implantation of COL-nanofiber scaffold seeded with cells induced more rapid subchondral bone emergence, and better cartilage formation, which led to better functional repair of osteochondral defects as manifested by histological staining, biomechanical test and micro-computed tomography data. Our study underscores the potential of using the bi-layer microporous COL-nanofiber scaffold for the treatment of deep osteochondral defects. 相似文献