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1.
Jin Wu Hao Wang Qing Li Qian-Ying Guo Si-Qi Tao Yu-Xian Shen Zheng-Sheng Wu 《Pathology, research and practice》2019,215(9):152523
Mammary carcinoma (MC) is one of most common malignancy in women, and ring finger protein 2 (RNF2) possesses various roles in vast human tumors. In MC tissues as well as in cell lines RNF2 exhibited high expression, had significant association with tumor size, lymph node status, TNM stage, patients’ poor survival, and promoted cell proliferation, colony formation, cell migration and invasion of MC cell lines which was mediated by downregulation of E-cadherin protein. These data reveal that RNF2 protein plays a vital role in the development of MC and may be a potential therapy target of MC. 相似文献
2.
A 1:1 adduct of methyl sorbate (MS) and 1,3‐di‐tert‐butylimidazol‐2‐ylidene (NHCtBu) initiates anionic polymerization of a nonconjugated polar alkene, allyl methacrylate (AMA) in toluene at ?20 °C. After the monomer is consumed quantitatively using a bulky aluminum Lewis acid, methylaluminum bis(2,6‐di‐tert‐butyl‐4‐methylphenoxide) (MAD), as an additive, successive ring‐closure occurs without highly dilute conditions to give a cyclic poly(AMA) containing α‐terminal MS unit, and an Mn of 8.8 × 103?58.5 × 103 with a narrow molecular dispersity index (Mw/Mn = 1.14–1.37). The lack of a need for dilution is due to the fact that an α‐terminal NHCtBu group is acting as the counter cation for the propagating center in the polymerization. From 1H NMR and matrix assisted laser desorption/ionization (MALDI‐TOF) mass spectra, combined with transmittance electron microscope (TEM) observation of a synthesized poly(AMA) with longer alkyl side chains prepared via a thiol‐ene click reaction, it is concluded that once the monomer is consumed, nucleophilic attack at the neighboring methine of the α‐terminal NHCtBu residue by the propagating anionic center causes ring‐closing to cyclic poly(AMA). 相似文献
3.
4.
3-(3-吡啶基)-6-芳基-7H-1,2,4-三唑并[3,4-b][1,3,4]噻二嗪的合成与波谱表征 总被引:2,自引:0,他引:2
目的:研究分子中含吡啶基的有多个杂环的化合物系列的波谱表征,方法:由烟酸出发,经多步反应,制得有吡啶基的均三唑并噻二嗪化合物,并进行红外,核磁共振氢谱与碳谱测试。结果:得到原料,中间体和产物的红外光谱图,产物的核磁共振氢谱与碳谱图。结论:标题化合物红外光谱1600cm^-1处多有C=N伸缩振动峰,1250cm^-左右有N-N=C伸缩振动峰,700cm^-1有C-S-C弯曲振动峰;噻二嗪亚甲基氢的化学位移δ值约为4.46,吡啶基四个氢原子化学位移约为9.3、8.9、8.7、8.0,噻二嗪亚甲基碳化学位移为23。 相似文献
5.
微小切口双重荷包缝合法矫正重度乳头内陷 总被引:7,自引:0,他引:7
目的 介绍一种疗效确切,创伤小,矫正重度乳头内陷的新术式.方法 设计切口位于乳晕第四象限,方向斜向外下方,呈放射状切口,长约1.5 cm,松解乳头基底部,切断牵拉的纤维条索,上提乳头,在距乳头0.8cm和1.5cm处,双重荷包缝合固定.结果 12例乳头内陷患者术后随访1个月至4年,均获得满意疗效.乳头横径、纵径、高度及外观明显改善.结论 该术式矫正乳头内陷具有切口小、创伤轻微、操作简单易行、效果确切、不易复发和并发症少等优点. 相似文献
6.
The calculation of the extent of the ring scotoma around positive lenses, as conventionally taught to students of clinical optics, indicates that the scotoma is of a significant size. Using knife-edge lenses this study shows that the calculations are invalid due to the finite size of the eye's entrance pupil and in many instances the scotoma is shown not to exist. The effect noticed in clinical practice is probably largely due to the frame and the edging techniques used which add to the refractive scotoma which is present with high powered lenses, large apertures and/or small pupil sizes. 相似文献
7.
Laurence Dorne Nadir Alikacem Robert Guidoin Michle Auger 《Magnetic resonance in medicine》1995,34(4):548-554
We have used 29Si solid-state nuclear magnetic resonance (NMR) spectroscopy to study the chemical structure of the silicone gels in virgin and explanted breast prostheses. Despite evidences of alteration in the morphological appearance of the silicone gel inside the breast prosthesis, our results do not reveal changes in the chemical nature and structure of the silicone gels after implantation. In addition to the main 29Si resonance peak at ?22.26 ppm that corresponds to the resonance frequency of the D repeat unit of the polysiloxane chains, the high sensitivity of our NMR technique allows the detection of very low concentrations of silicone compounds. Within our experimental detection limit of 0.2%, no signal between ?90 ppm and ?150 ppm are observed. This indicates that no silica products are present inside the gel of the prostheses. Furthermore, our 29Si NMR spectra indicate differences in the chemical compositions of the silicone gels from different manufacturers. 相似文献
8.
Tsutomu Ogata Peter Goodfellow Christine Petit Pierre Maroteaux Nobutake Matsuo 《American journal of medical genetics. Part A》1993,45(1):101-104
This is a follow-up report on a male patient with a 46, Y, r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean – 5.6 S.D.). © 1993 Wiley-Liss, Inc. 相似文献
9.
Jack C. Kim 《Archives of pharmacal research》1994,17(3):204-206
A regioselective preparation of 10-methoxy-11-hydroxyaporphine (“Apocodeine,1b”) from (R,S)-10, 11-dihydroxyaporphine(apomorphine,1a) is described. The isopropylidene ketal ring of 10,11-(isopropylidenyldioxy) aporphine (2) obtained by the isopropylidenation of apomorphine, was regioselectively opened by the ten equivalent of trimethylaluminum
to give 10-hydroxy-11-t-butyloxyaporphine (3). The free 10-hydroxyl position of 3 was methylated with methyl p-toluenesulfonate/NaH, and afforded 10-methoxy-11-t-butyloxyaporphine
(4) in high yield. Selective debutylation gave the desired 10-methoxy-11-hydroxyaporphine (“apocodeine”,1b) in good yield. 相似文献
10.
Summary Nerve regeneration was studied in a model of centrocentral anastomosis (CCA) performed on the sciatic nerve of the rat. Experimental CCA was made by suturing the proximal end of the peroneal branch on the proximal end of the sural branch, placing between them a peroneal nerve graft (Group I, 20 rats) or a silicone chamber (Group II, 12 rats). Nerve grafts had a length of 5mm and silicone chambers 7 mm. In six silicone chambers an 1 mm nerve graft was placed in the centre of the tube. In group I animals anterograde degeneration was studied by cutting the graft 60 days after surgery. In group II, nerve regeneration was studied 2, 4 and 8 weeks after surgery. Results indicate that in CCA: 1) regenerated axons coming from one nerve end grow into the graft but do not cross the contralateral suture line; 2) regeneration is poorer in silicone chambers than in nerve grafts; and, 3) in silicone chambers regeneration is related to time. The reduction in the regenerative capability in CCA seems to be related to the alteration of nerve sprouts aiming for the peripheral targets. 相似文献