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201.
202.
Basic LM, TEM, SEM, and FFR appearances of a pure line of normal human melanocytes derived from foreskin, and a human melanoma line, in cell culture are described. Normal melanocyte cultures exhibit side by side, cells of widely different melanogenic activities--possible clones--and melanosomes of bizarre shape and internal structure are frequent. Aggregates of melanosomes, with or without associated amorphous material, and with no discernible limiting membrane are present within many cells, and occasional simple specialised contacts occur between apposed cells. On replicas of plasma membrane of normal melanocytes, particle densities and diameters on P and E fracture faces were within the ranges for cells in general, and equivalent data for the melanoma cells were not significantly different. Similarly, there was no difference in density of distribution or diameter of nuclear pores between the normal and the tumoural cells.  相似文献   
203.
Cultures of human melanoma cell line B0008 were exposed to the disodium salts of azelaic acid (C9 2Na), adipic acid (C6 2Na) and dodecanediaic acid (C12 2Na) at 10(-2) M and 5 x 10(-2) M for 24 hrs. None of the diacid salts had a significant effect on growth rate or viability of the cells, at 10(-2) M for 24 hrs nor had C6 2Na any effect at 5 x 10(-2) M. At 5 x 10(-2) M for 24 hrs, both C9 2Na, and C12 2Na had a significant effect in reducing both growth and viability. These effects were accompanied by morphological evidence of cell death, and swelling of mitochondria and accumulation of lipid droplets within cytoplasm of still viable cells.  相似文献   
204.
A potent gonadotropin releasing hormone (GnRH) agonist, D(Nal2)6 GnRH (Nafarelin) has been administered to two groups of normal men for 16 weeks by two routes in order to assess its effectiveness in suppressing spermatogenesis. In this report 400 micrograms of the GnRH agonist was given daily by constant subcutaneous infusion and the results compared to an earlier study in which 200 micrograms of the same agonist was given as a single daily subcutaneous injection. All subjects in both groups received an intramuscular injection of testosterone enanthate (200 mg) every two weeks to prevent symptoms of androgen deficiency. The higher dose infusion regimen was much more effective in suppressing spermatogenesis than the single daily injection. With infusion treatment, 3 of 7 subjects were azoospermic, a fourth subject had less than 1 million sperm per ml of semen and 5 of 7 subjects had sperm counts less than 5 million per ml. Because of the differences in GnRH dose it is unclear if the enhanced effect seen in the infusion group is the result of the route or dose of drug. Data from experimental animals and short term comparative studies with two routes and two doses suggest that both mechanisms may be operative. In either case, the results are the most promising to date and raise the possibility that constant delivery of a higher dosage of agonist could produce azoospermia in most or all subjects.  相似文献   
205.
206.
Data are presented on AB0 and RhD blood groups in 186 patients suffering from carcinoma of cervix uteri and 274 controls from Delhi, India. A strong association is observed between carcinoma patients and blood group A, and a slightly weaker association with blood group B. There is no significant association with RhD blood group. The available data in other populations confirm the association with AB0 blood group.  相似文献   
207.
Quantitative analysis of C-band size heteromorphisms in chromosomes 1,9 and 16 was carried out in 200 Delhi newborns (100 males and 100 females). The percent size heteromorphisms for chromosomes 1,9 and 16 showed nonsignificant differences between the sexes. Homozygous size level combinations showed higher incidence than the heterozygous combinations for all the three chromosome pairs studied in both sexes. Our results are compared with other reported studies and the possible role of these heteromorphisms in ethnic/racial variation and in developmental disturbances is discussed.  相似文献   
208.
Highly functionalized morphan derivatives were synthesized from nitroalkene 2′-(oxoalkyl)-C-glycosides by a tandem reaction that created three (two C–N and one C–C) new bonds and four stereogenic centers in a one-pot procedure under very mild conditions without the use of expensive reagents. The transformation was achieved from a β-elimination/Michael addition cascade, followed by Michael addition of the amine and intramolecular enamination. In the presence of sodium cyanoborohydride the iminium intermediate was reduced in situ to afford the desired morphans.  相似文献   
209.
Genetic markers and malaria. Observations in Gujarat, India   总被引:2,自引:0,他引:2  
189 healthy controls and 175 patients suffering from malaria vivax have been investigated with regard to associations between this disease and 22 genetic polymorphisms of the blood (ABO, MN, Ss, Rh, Kell, P, Lutheran, Kidd, Duffy, Diego, Xg; ABH-Secretor; Hp, Gc, Gm, Km; aP, AK, PGM1, 6-PGD, EsD; Hb variants) Significant associations could be demonstrated only for P and Hp systems, though in accordance with other investigations it cannot be excluded that the ABO system plays also a role in this connection.  相似文献   
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