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1.
通过IR方法,观测并讨论了在不同条件下制备的超高分子量PE(UHMPE)凝胶膜中旁式(G构象)构象与超拉伸性的关系,提出了G构象浓度及分布对UHMPE凝胶膜超拉伸性影响的新概念,同时也讨论了它与链缠结之间的联系,发现:反映G构象的相对浓度的比值σ=I1303I1352随制膜浓度的增大而增加,在临界浓度C0(0.4-0.5g100ml)附近所形成的膜,具有超高拉伸性(λ=200),其G构象的变化与M  相似文献   

2.
利用量子化学从头算方法在HF/6-31G水平上,优化计算了带2个负电荷的封闭型硼烷B15H15^2-(D3h)的结构、能量和正则振动频率。该硼烷的简正振动频率计算表明,它是HF/6-31G势能超曲面上的真实稳定点。理论预测它在化学上和动力学上都是稳定的。  相似文献   

3.
甘氨酸的杂多酚超分子化合物的合成及性质研究   总被引:14,自引:1,他引:13  
首次合成了甘氨酸的Keggin结构杂多酸超分子化合物(HGly)3「PW12O40」.5H2O(HGly)4「SiW12O40」.4H2O,用元素分析,IR,UV,TG-DTA,XRD和NMR等方法对标题化合物进行了表征,并讨论了它们的合成条件及结构特性。  相似文献   

4.
评述了Ge-132的安全性,对大鼠口服Ge-132代谢产物的研究表明,Ge-132的基本骨架GeCH2CH2COOH没有变化,即它不会降解为GeO2或其他的无机锗化合物。  相似文献   

5.
考察了在具有Pentasil孔道结构的H-Ga-Si与Pt/H-Ga-Si杂原子分子筛及HZSM-5分子筛催化剂上的丙烷芳构化。Pt/H-Ga-Si有较高催化活性和芳烃选择性,用XRD、TEM和TPR等技术对催化剂进行了表征,讨论了Pt与Ga的相互作用。Pt/H-Ga-Si为双功能催化剂,Pt促进烷烃脱氢成为烯烃,还能降低丙烷裂解活性,而且可稳定骨架Ga,使其不易脱除;Ga可以提高中间烯烃转变为芳烃的选择性。H-Ga-Si与HZSM-5上的丙烷芳构化机理不同。H-Ga-Si上为丙烷脱氢机理,Ga脱去H+形成活泼正碳离子,同时由于骨架Ga与分子筛B酸位相邻,所以可提高芳烃选择性;HZSM-5上丙烷活化是经过裂化机理,再通过氢转移步骤形成芳烃。  相似文献   

6.
侧脑室注射氯化镧对大鼠血清生长素和甲状腺素的影响   总被引:3,自引:0,他引:3  
西方研究了侧脑室注入LaCl3对大鼠血清中生长系,甲状腺素,促甲状腺素和下丘脑中生长抑素的影响。侧脑室注射0.001和0.01mol.l^-1LaCl3,血清中T4和GH含量明显高于对照组,0.1和0.5mol.l^-1LaCl3组血清T4和GH未见明显变化。  相似文献   

7.
聚丙烯酰胺/柠檬酸铝胶态分散凝胶性质的研究   总被引:28,自引:0,他引:28  
用低浓度不同分子量的部分水解聚丙烯酰胺( H P A M) 和柠檬酸铝制备了胶态分散凝胶( C D G) ,并用奥氏粘度计、超细粒度分析仪、岩芯流动实验对 C D G 的性质进行了研究.结果表明, C D G 的粘度比 H P A M 粘度低,粒径在450 ~520n m 之间.岩芯流动实验结果表明, C D G 能够使岩芯的流动阻力大幅度增加,且在岩芯中达到同样的流动阻力所需通过 C D G 的体积与形成 C D G 的 H P A M 的分子量、浓度及岩芯渗透率有关.  相似文献   

8.
HIGHACTIVITYFUSEDIRONCATALYSTFORCOHYDROGENATIONTOHIGHERALCOHOLSSuYunlai,GuoYiqun,WangWenxiang,ZhangYuanzhen(CatalysisResearch...  相似文献   

9.
取代型钨镓杂多配合物的导电性及其磁性   总被引:11,自引:1,他引:11  
合成了过渡金属取代的钨镓杂多配合物α-Na7「GaW11Co(H2O)O39」.16H2O,α-Na7H2「GaW10Co2(H2O)2O39」.16H2O和α-NanHm「GaW9ME(H2O)3O37」.16H2O「M=Co(Ⅱ),Ni(Ⅱ,)V(Ⅴ)」,通过红外,紫外,ICP,TG-DTA,EPR,XPS,^183WNMR,极谱等手段进行了表征。  相似文献   

10.
合成了以4,4-bpy为中继基,Gly,GlyO为螯环的新型双核铜配合物。经X射线单昌结构分析确定该配合化合物的化学式为「(H2CCH2CONHCH2COO)Cu(OH)Cu(OH)(C10H8N20Cu(OH)-(H2NCH2CONHHCH2OO).」10H2O。  相似文献   

11.
12.
目的就针灸治疗多囊卵巢综合征致不孕症的临床疗效进行观察与探究。方法选择广州市天河区冼村街社区卫生服务中心自2013年4月至2015年5月期间收治的多囊卵巢综合征致不孕症患者66例,依据患者来院先后顺序平均分为参照组和观察组,每组患者33例。参照组患者予以常规治疗,观察组患者采用针灸治疗,最后比对两组患者的临床治疗效果。结果经不同方法治疗后,观察组患者各项指标的改善程度好于参照组,妊娠率和排卵率也均高于参照组,组间统计后差异显著。结论在多囊卵巢综合致不孕症患者治疗中应用针灸,其临床效果显著,具有临床应用价值。  相似文献   

13.
目的探讨多囊卵巢综合征患者冻融胚胎移植子宫内膜准备的两种方案的效果。方法选择2014年3月到2016年3月间在深圳武警医院选择行冻融胚胎移植子宫内膜准备的700例多囊卵巢综合征患者作为研究对象,对所有患者的临床资料进行回顾性分析,根据患者子宫内膜准备方案分为人工组(n=350)和促排卵组(n=350),对比两组患者冻融胚胎移植效果。结果人工组患者胚胎复苏率、优质胚胎率、移植胚胎数、子宫内膜厚度、胚胎种植率、妊娠率与促排卵组相比均无差异,P0.05。结论人工子宫内膜与促排卵内膜效果相似,均可推广运用。  相似文献   

14.
Two new analogs of the releasing factor of the luteinizing hormone with shortened amino acid sequences have been synthesized by the methods of classical peptide chemistry. The influence of the preparations on the action of chorionic gonadotropin and on the course of processes of ovulation in experimental animals has been studied. The promising nature in this direction of the search for active analogs for luliberin has been shown.  相似文献   

15.
《Analytical letters》2012,45(18):2900-2908
A dual-label time-resolved fluorescence immunoassay (TRFIA) for the simultaneous determination of β human chorionic gonadotropin and progesterone was developed for the early diagnosis of ectopic pregnancy. The performance of this assay was evaluated using clinical serum and then compared with standard procedures. The sensitivity for β human chorionic gonadotropin detection was 1 U/L (linear dynamic range, 0–8000 U/L), and the sensitivity for progesterone detection was 0.05 ng/mL (linear dynamic range, 0–50 ng/mL). High correlation coefficients (R2) were obtained between the reported immunoassay and standard methods (R2 = 0.99 for β human chorionic gonadotropin, R2 = 0.97 for progesterone). The present dual-label TRFIA has high sensitivity, specificity, and accuracy in clinical analyses and is a suitable alternative to the single-labeled diagnostic methods.  相似文献   

16.
Fellegv&#;ri  I.  Valk&#;  K.  V&#;radi  G.  Bauer  P.  Kramer  M. 《Chromatographia》1989,27(11):601-604
Chromatographia - A high-performance liquid chromatography (HPLC) method was developed for the purification of 50mg crude human chorionic gonadotropin (HCG) hormone sample in one chromatographic...  相似文献   

17.
《Analytical letters》2012,45(13):2145-2158
Abstract

We report a sensitive high performance liquid chromatography (HPLC) method for determination of free and conjugated estrogens (estrone, estradiol and estriol) by a fluorescent pre-labeling regent, 2-(4-carboxyphenyl)-5,6-dimethylbenzimidazole, with modification of previous work. The modified method was also tried, in preliminary work, for diagnosis of the in-vitro fertilization embryo transfer (IVF-ET) process. The reagent volumes were changed to one-tenth, derivatization conditions were changed to mild conditions at 40 C, and a solid-phase extraction process by SEP-PAK could be omitted after restudy of reaction conditions. As a result analysis time could be shorted within 40 min. The proposed HPLC method was applied to monitoring of free and conjugated estrogens in the patients who attend in-vitro fertilization embryo transfer (IVF-ET). The subsequent increase of free and conjugated estrone, estradiol and estriol was observed with the progress of follicle growth following ovulation stage in the IVF-ET process. We tried to plot estrogens for assist of clinical diagnosis of IVF-ET. The free estrone: 200-600 pg/ml, estradiol: 200-600 pg/ml and estriol: 100-300 pg/ml, conjugate estrone: 1000-5000 pg/ml, estradiol: 3000-8000 pg/ml and estriol: 2000-7000 pg/ml) in the patients without hormone disease were observed before human chorionic gonadotropin stimulation (hCG) on IVF-ET process. It was expected that free estrogen values, especially E1 and E3 could be use as validation products for diagnosis of hormone disease in IVF-ET process.  相似文献   

18.
Linifanib is known as an inhibitor of receptor tyrosine kinase. Even though it has been widely recognized as efficient inhibitor of receptor tyrosine kinases, anti-carcinogenic effect has not been investigated enough in ovarian cancer. In this study, we investigated the anti-cancer effect of linifanib on human ovary cancer SKOV3 cells. WST-1, cell counting assay, and observation of morphological changes were performed to evaluate the cytotoxic effect of linifanib in SKOV3 cells. We analyzed SKOV3 cells treated with linifanib using Muse cell analyzer. We focused on investigating the effect of linifanib on DNA damage in nucleus. Additionally, intracellular reactive oxygen species (ROS) level was measured through Muse cell analyzer. Western blotting was performed to evaluate the protein expression level related to apoptosis. We found that linifanib inhibited proliferation of SKOV3 cells. Our results showed that linifanib induced apoptosis in SKOV3 cells. Additionally, linifanib induced DNA damage in SKOV3 cells. We found that intracellular ROS level increased after treatment of linifanib in SKOV3 cells. Interestingly, FOXO3 was transferred from cytosol into nucleus after linifanib treatment. Taken together, our results supported that linifanib inhibited the proliferation of human ovary cancer SKOV3 cells, which suggested that linifanib might have the potential to be developed as drugs for ovarian cancer treatment.  相似文献   

19.
In rats with polycystic ovary syndrome (PCOS) induced by injection of estradiol valerate (EV), unilateral or bilateral section of the vagus nerve restores ovulatory function in 75% of animals, suggesting that the vagus nerve participates in the development of PCOS. Since the vagus nerve is a mixed nerve through which mainly cholinergic-type information passes, the objective of the present study was to analyze whether acetylcholine (ACh) is involved in the development of PCOS. Ten-day-old rats were injected with 2.0 mg EV, and at 60 days of age, they were microinjected on the day of diestrus in the bursa of the left or right ovary with 100 or 700 mg/kg of ovarian weight atropine, a blocker of muscarinic receptors, and sacrificed for histopathological examination after the surgery. Animals with PCOS microinjected with 100 mg of atropine showed a lack of ovulation, lower serum concentrations of progesterone and testosterone, and cysts. Histology of the ovaries of animals microinjected with 700 mg of atropine showed corpus luteum and follicles at different stages of development, which was accompanied by a lower concentration of progesterone and testosterone. These results allow us to suggest that in animals with PCOS, ACh, which passes through parasympathetic innervation, is an important component in the persistence and development of the pathophysiology.  相似文献   

20.
Polycystic ovary syndrome (PCOS) is a common multisystem disease with reproductive, metabolic and psychological abnormalities. It is characterized by a high prevalence rate in women of childbearing age and highly heterogeneous clinical manifestations, which seriously harm women’s physical and mental health. Quercetin (QUR) is a natural compound of flavonoids found in a variety of foods and medicinal plants. It can intervene with the pathologic process of PCOS from multiple targets and channels and has few adverse reactions. It is mentioned in this review that QUR can improve ovulation disorder, relieve Insulin resistance (IR), reduce androgen, regulate lipid metabolism, regulate gut microbiota and improve vascular endothelial function, which is of great significance in the treatment of PCOS.  相似文献   

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