Optically Active Trisulphides and Tetrasulphides Related to L-Cystine

A . description is ,given of the preparation and properties of optically active bis(2-carboxy - 2- phthalimidoethyl) disulphide (Ia), [a]D-275°, bis(2-carboxy -2.:phthalimidoethyl) trisulphide (lb) , ,[a]D -4720 and bis(2-c arboxy -2-phthalimidoethyl) tetrasulphide (le), [a]D:--3880. The starting material for these compounds was N - -phthaloyl-L-cysteine (II), [a]D-64° prepared from L-cysteine hydrocl).loride and sodium o- carbethoxythiobenzoa te

Influence of ploughshare surface layers on ploughing efficiency

The paper presents comparison between standard ploughshares made of manganese steel 50Mn7 and the authors’ ploughshares hardfaced with a layer of C-Co-Cr-Ni-Si on the same steel. The research was carried out by using two tractors with two four-furrow plough of the same power in a total of 360 working hours, and a total of 180 hours of ploughing with each ploughshare. Ploughshares were used to measure hardness, to analyse the structure and wear

MAGE-A3/4 and NY-ESO-1 antigens expression in metastatic esophageal squamous cell carcinoma

In the present study we analyzed immunohistochemical expression of MAGE-A 3/4 and NY-ESO-1 in 55 samples of esophageal squamous cell carcinomas (ESCC) and their respective lymph node metastases. To our knowledge this is the first study to assess and compare the expression of these antigens in ESCC lymph node metastases