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991.
目的探讨影响采用人工周期准备内膜冻融胚胎移植(frozen embryo transfer,FET)妊娠结局的相关因素,以期为临床提高FET妊娠率提供一定的指导。方法回顾分析武汉大学人民医院生殖中心2011年1月—2014年12月按人工周期准备内膜行FET的930例的临床资料,受精方式包括体外受精(IVF)和卵胞浆内单精子注射(ICSI),采用阴道B超监测内膜厚度,记录人工周期准备内膜行冻融胚胎移植的不孕妇女决定移植日血清雌二醇(E2)、孕酮(P)水平,并计算E2/P比值,分析不孕原因、不孕年限、年龄、促排卵用药方案、受精方式、内膜厚度、优质胚胎数、E2、P及E2/P等与FET临床妊娠结局的关系,并进一步采用多因素logistic回归模型分析影响妊娠结局的相关因素。结果不孕年限、年龄、子宫内膜厚度、P水平、E2/P及优质胚胎数与临床妊娠结局有一定相关性(P0.05,P0.01);logistic回归分析显示,年龄、子宫内膜厚度、E2/P为临床妊娠结局的影响因素(P0.05,P0.01)。结论对采用人工周期准备内膜行FET的患者重点调控子宫内膜厚度、E2/P可提高临床妊娠率;筛选适龄患者亦是提高妊娠率的重要手段。 相似文献
992.
Wei-Lin Zhang Hong-Zheng Meng Mao-Wei Yang 《International journal of medical sciences》2015,12(5):441-449
Diabetic osteoporosis is gradually attracted people''s attention. However, the process of bone microstructure changes in diabetic patients, and the exact mechanism of osteoblast iron overload are unclear. Therefore, the present study aimed to explore the function of DMT1 in the pathological process of diabetic osteoporosis. We build the type two diabetes osteoporosis models with SD rats and Belgrade rats, respectively. Difference expression of DMT1 was detected by using the method of immunohistochemistry and western blotting. Detection of bone microstructure and biomechanics and iron content for each group of samples. We found that DMT1 expression in type 2 diabetic rats was higher than that in normal rats. The bone biomechanical indices and bone microstructure in the rat model deficient in DMT1 was significantly better than that in the normal diabetic model. The loss of DMT1 can reduce the content of iron in bone. These findings indicate that DMT1 expression was enhanced in the bone tissue of type 2 diabetic rats, and plays an important role in the pathological process of diabetic osteoporosis. Moreover, DMT1 may be a potential therapeutic target for diabetic osteoporosis. 相似文献
993.
Jianjun?Zhang Guangyuan?Meng Chen?Zhang Lin?Lin Nuo?Xu Min?Liu Fangyuan?Cui Le?JiaEmail author 《BMC complementary and alternative medicine》2015,15(1):440
Background
Edible mushrooms, especially the genus of Pleurotus, have been well studied for their nutrition as well as non-toxic medicinal properties. Recently, much attention has been paid to the therapeutic values of mushrooms in genus of Pleurotus with diabetes mellitus (DM), which was a complex metabolic disorder that induced by increased oxidative stress and characterized by hyperglycemia. However, scare attention has been paid to polysaccharides from P. djamor. Meanwhile, zinc is an essential trace element in the human body and it participates in various pathways of metabolism. Therefore, the objective of present study was aimed to evaluate the protective effects of the three extractable mycelium zinc polysaccharides (MZPS), including acidic-MZPS (Ac-MZPS), alkalic-MZPS (Al-MZPS) and enzymatic-MZPS (En-MZPS), on the liver and kidneys in diabetic mice induced by streptozocin (STZ) aiming to better understand the possible hypoglycemic mechanisms and their health benefits.Methods
The Ac-, Al-, and En-MZPS were extracted with hydrochloric acid (1 M), sodium hydroxide (1 M) and snailase (4 %) from P. djamor zinc-enriched mycelium, respectively. The diabetic mice were induced by injection of STZ. Besides the histopathological analyses of liver and kidney, the following biochemical analysis were processed to investigate the antioxidative effects, including activities of superoxide dismutase (SOD), GSH peroxide (GSH-Px) and catalase (CAT), and contents of malondialdehyde (MDA) in liver and kidney homogenate; activities of alamine aminotransferase (ALT) and aspertate aminotransferase (AST), and levels of urea nitrogen (BUN), creatinine (CRE), total cholesterol (TC), albumin (ALB), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein choles-terol (LDL-C) and very low-density lipoprotein cholesterol (VLDL-C) in serum.Results
Results showed that the activities of SOD, GSH-Px and CAT were significantly increased, the MDA contents remarkably reduced, and the values of ALT, AST, BUN, CRE, TC, LDL-C and HDL-C observably mitigated in the liver, kidneys and serum of diabetic mice by these three polysaccharides treatment. Biochemical and histopathological analyses also showed that MZPS could alleviate liver and kidneys injury.Conclusion
These results demonstrated that Ac-, Al-, and En-MZPS possessed potent antioxidant activities, and could be used as a potentially functional food for the prevention of diabetes and its complications induced by STZ.994.
Shuping Zhang Xing Ke Suyun Zeng Meng Wu Jianfang Lou Lei Wu Peijun Huang Lei Huang Fang Wang Shiyang Pan 《Cellular & molecular immunology》2015,12(5):580-591
Regulatory T (Treg) cells may participate in mediating a suppressive microenvironment that blunts successful anti-tumor immunotherapy. Recent studies show that CD8+ Treg cells might impede effective immune responses to established tumors. However, there is limited research regarding CD8+ Treg cells in ovarian cancer (OC) patients. Here, we investigated CD8+ Treg cells in OC patients and their in vitro induction. The immunohistochemistry of tumor-infiltrating lymphocytes revealed a significant correlation between the intratumoral CD8+ T cells and the forkhead box p3 (Foxp3)+ cells in the intraepithelial and stromal areas of advanced OC tissues. We examined the expression of Treg markers in CD8+ T cells from the peripheral blood and fresh tumor tissues of OC patients using flow cytometry. Our results indicated an increase in the CD8+ Treg cell subsets of OC patients compared with those in patients with benign ovarian tumors and healthy controls, including an increased expression of CD25, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), and Foxp3 and decreased CD28 expression. To demonstrate whether the tumor microenvironment could convert CD8+ effector T cells into suppressor cells, we used an in vitro transwell culturing system. Compared with the CD8+ T cells cultured alone, the CD8+ Treg cells induced in vitro by coculture with SK-OV-3/A2780 showed increased CTLA-4 and Foxp3 expression and decreased CD28 expression. In addition, the in vitro-induced CD8+ Treg cells inhibited naïve CD4+ T-cell proliferation, which was partially mediated through TGF-β1 and IFN-γ. Our study suggests that CD8+ Treg cells were increased in OC patients and could be induced in vitro, which may be the way that tumors limit antitumor immunity and evade immune surveillance. 相似文献
995.
Bei-Ping Miao Rui-Shi Zhang Meng Li Yun-Ting Fu Miao Zhao Zhi-Gang Liu Ping-Chang Yang 《Cellular & molecular immunology》2015,12(6):750-756
The prevalence of nasopharyngeal cancer (NPC) is high in the southern area of China and some other districts in the world. The pathogenesis of NPC is unclear. It is reported that some microRNAs (miR) are involved in the progression of NPC. This study aims to investigate the role of miR-21 in the induction of immune tolerance of NPC. In this study, NPC tissue was collected from patients with NPC. Assessment of miR was performed with real time quantitative RT-PCR. Western blotting was used to assess proteins of interleukin 10 and nuclear factor I-A (NFI-A). Immune cells were analyzed by flow cytometry. The results showed that NPC cell line C666-1 and surgically removed NPC tissue expressed miR-21, which was upregulated by the presence of the Toll-like receptor 3 ligand, Poly I: C. Exposure to miR-21 increased the expression of NFI-A and interleukin (IL)-10 in naive B cells. High frequency of IL-10+ B cells was detected in the NPC tissue. The NPC- or miR-21-primed B cells suppressed cytotoxic CD8+ T cell activities. We conclude that NPC-derived miR-21 induces IL-10+ B cells; the latter is capable of suppressing CD8+ T-cell activities. miR-21 may be a potential target in the treatment of NPC. 相似文献
996.
Xiangsheng Xu Qinghua Shang Xinyue Chen Weimin Nie Zhengsheng Zou Ang Huang Ming Meng Lei Jin Ruonan Xu Ji-Yuan Zhang Junliang Fu Lifeng Wang Zirong Tang Yunbo Xie Xiaoming Yang Zheng Zhang Fu-Sheng Wang 《Cellular & molecular immunology》2015,12(3):309-316
B cells play an important role in the clearance of hepatitis B virus (HBV) and protection against reinfection. However, the functional characteristics of these cells that are associated with the outcome of chronic HBV infection remain unknown. We comprehensively investigated the frequency, phenotype, and function of peripheral B-cell subsets from CHB patients in different phases: immune tolerance (IT), immune activation (IA), immune clearance (IC), responders with HBsAg seroconversion (resolved patients, RP), and healthy controls (HC). IA patients displayed lower percentages of peripheral blood memory B cells compared with the other groups. Overall polyclonal activation of B cells, indicated by higher levels of activation markers and secretion of IgG and IgM, was observed in IA patients. This B-cell hyperactivation could be induced by increased IFN-α and soluble CD40 ligands in IA patients. Notably, the expression of the co-stimulator molecule CD80 and serum HBsAb and the frequency of HBsAg-specific B cells were significantly decreased in IT, IA, and IC patients compared with HC subjects. More importantly, the B-cell hyperactivation, co-stimulatory molecule downregulation and HBsAg-specific B-cell impairment were reversed in RP patients. The reversal of B-cell hyperactivation and functional impairment is associated with HBsAg seroconversion in chronic hepatitis B patients. 相似文献
997.
目的 研究肿瘤标志物在良恶性胸腹水的临床鉴别价值.方法 169例恶性胸腹水患者设为恶性腹水组,146例良性胸腹水设为良性组,比较两组胸腹水癌胚抗原(CEA)、甲胎蛋白(AFP)、糖类抗原(CA) 125、CA19-9水平,并对各肿瘤标志物对良恶性胸腹水的诊断进行方法学评价.结果 恶性组的CEA为(139.7-±56.4) ng/mL、AFP为(189.2±45.2) ng/mL、CA125为(314.7±86.2) U/mL、CA19-9为(158.5±24.2) U/mL,浓度均高于良性组,差异有统计学意义(均P<0.05);ROC曲线分析CEA、AFP、CA125以及CA19-9曲线下面积分别为0.811、0.547、0.715和0.769,其对应的诊断切点分别为5.6 ng/mL、63.7 ng/mL、38.9 U/mL和30.4 U/mL;AFP因ROC曲线下面积过低不适于恶性胸腹水的诊断.三种肿瘤标志物单独检测方法学评价的各项指标均以CEA最好,灵敏度为75.7%,特异度为88.6%,联合检测以CEA、CA125以及CA19-9的联合检测效果较好,灵敏度为80.5%,特异度为94.0%.结论 肿瘤标志物联合检测对胸腹水的性质鉴别方面有重要的临床应用价值. 相似文献
998.
999.
Jun Dong Meng Lu Teng Lu Baobao Liang Junkui Xu Jie Qin Xuan Cai Sihua Huang Dong Wang Haopeng Li Xijing He 《Clinics (S?o Paulo, Brazil)》2015,70(7):493-499
OBJECTIVE:To determine the range of motion and stability of the human cadaveric cervical spine after the implantation of a novel artificial disc and vertebra system by comparing an intact group and a fusion group.METHODS:Biomechanical tests were conducted on 18 human cadaveric cervical specimens. The range of motion and the stability index range of motion were measured to study the function and stability of the artificial disc and vertebra system of the intact group compared with the fusion group.RESULTS:In all cases, the artificial disc and vertebra system maintained intervertebral motion and reestablished vertebral height at the operative level. After its implantation, there was no significant difference in the range of motion (ROM) of C3–7 in all directions in the non-fusion group compared with the intact group (p>0.05), but significant differences were detected in flexion, extension and axial rotation compared with the fusion group (p<0.05). The ROM of adjacent segments (C3−4, C6−7) of the non-fusion group decreased significantly in some directions compared with the fusion group (p<0.05). Significant differences in the C4-6 ROM in some directions were detected between the non-fusion group and the intact group. In the fusion group, the C4−6 ROM in all directions decreased significantly compared with the intact and non-fusion groups (p<0.01). The stability index ROM (SI-ROM) of some directions was negative in the non-fusion group, and a significant difference in SI-ROM was only found in the C4−6 segment of the non-fusion group compared with the fusion group.CONCLUSION:An artificial disc and vertebra system could restore vertebral height and preserve the dynamic function of the surgical area and could theoretically reduce the risk of adjacent segment degeneration compared with the anterior fusion procedure. However, our results should be considered with caution because of the low power of the study. The use of a larger sample should be considered in future studies. 相似文献
1000.
Liu Yan Long Pan Fu Qiang Tao Ling Zhang Yan Wei Zhang Yu Long Meng Shan Li Shi Rong Li Hong Li 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(8):1465-1471
The present study was to examine the distribution of lymphatic vessels in the penis of normal adult males, which could provide an anatomical basis for improvement of incisions in penile lengthening surgery, and may also help to prevent postoperative refractory edema. Thirteen normal adult male volunteers were recruited for this study. Contrast agent was injected subcutaneously in the foreskin of the penis, and after two minutes magnetic resonance lymphangiography (MRL) was performed. The acquired magnetic resonance images were analyzed to determine the changes in the number and diameter of lymphatic vessels in different parts of the penis. Maximum intensity projections (MIP) and materializes interactive medical image control system (MIMICS) were applied to analyze the overall distribution of lymphatic vessels in the penis. Magnetic resonance imaging (MRI) showed that the lymphatic vessels were in conspicuous contrast with surrounding tissues and could be clearly identified. Penile lymphatic vessels were clearly visible in the root of the penis. At the junction of the penis and the abdominal wall, all lymphatic vessels were found to be concentrated in the dorsal part of the penis. MIP two‐dimensional reconstruction showed that the overall distribution of relatively large lymphatic vessels in the dorsal and ventral parts of the penis could be seen clearly on bilateral 45° position, but not inside the abdominal wall because some of lymphatic vessels were overlapped by other tissues in the abdomen. MIMICS three‐dimensional reconstruction was able to reveal the overall spatial distribution of lymphatic vessels in the penis from any angle. The reconstruction results showed that there were 1–2 main lymphatic vessels on the root of dorsal penis, which coursed along the cavernous to the first physiological curvature of the penis. Lymphatic vessels merged on both sides of the ventral penis. At the root of the penis, lymphatic vessels gradually coursed to the dorsal surface of the penis and folded at the abdominal wall to the outside, and finally merged into the inguinal lymph nodes. The changes in distribution, number and diameter of the lymphatic vessels in the penis were observed by MRI. MIP and MIMICS reconstructions directly revealed the anatomical features of penile lymphatic vessels such as spatial distribution, overall alignment, and the relations to adjacent structures, drainage and reflux. The study will provide the anatomical basis for penile surgery, penile lymphatic reflux disorders caused by trauma or lymphatic vessels obstruction, and lymph node metastasis in penile cancer. Anat Rec, 298:1465–1471, 2015. © 2014 Wiley Periodicals, Inc. 相似文献