SIDOROVA Ms. V. F.; Dr.Biol. - Inst, of Human Morphol., Acad, of Med. Sci. of the USSR, Tsurupa 



St. 3, MOSCOW 1 17469, U.S.S.R. 

 SIEBERS, A. M.; Drs. - Bot. Lab., State Univ., Nonnensteeg 3, LEIDEN, Netherlands 

 SIETSMA, J. H.; Dr. - Dept. of Developm. Plant Biol., State Univ. of Groningen, Biol. Ctr., 



Kerklaan 30, 9751 NN HAREN (Gr.), Netherlands 

 a Composition of the cell wall (chemical analysis, enzymatic degradation) in relation to develop- 

 ment. SchizophyUum commune (Basidiomycetes, Fungi) 

 b Biochemistry of waU formation. Same species as a 

 SILVERS, J.; Dr.med. - Abt. Neuroanat., Anat. Inst, der Univ., Martinistr. 52, 2000 HAMBURG 20, 



B.R.D. (Germany) 

 a Ultrastructure of brain and retina development. Rattus spec. (Rodentia) 

 b Development of monoamine containing neurons. Same species as a 

 SEEWING, R.; oProf. - Inst, fiir Zool., Lehrst. I, Univ. Erlangen-Nurnberg, Universitatsstr. 19, 8520 



ERLANGEN, B.R.D. (Germany) 

 a Development of body segmentation. (Brachiopoda, Phoronidea) 

 b Metamorphosis. Actinotrocha spec. (Phoronidea) 



SIGNORET, J.; D.Sc, Prof. - Lab. d'Embryol., U.E.R. de Sci., Univ. de Caen, 14032 CAEN, France 

 a La cinetique cellulaire au cours de la segmentation; modalites, determinisme, signification. 



Ambystoma mexicanum (Urodela) 

 b Study of nuclear differentiation and specific activities by means of nuclear transplantation. Same 



species as a 

 c DNA rephcation during cleavage (initiation, asynchrony, enzymes). Same species as a 

 SIMKISS, K.; Ph.D., Prof. - Dept. of Zool., Univ. of Reading, READING RG6 2AJ, England 

 a Calcium pumps in the chorioallantoic membrane and their role in transporting ions from eggshell 



to embryo. GaUus domesticus (Aves) 

 b Electrolyte movements from chorion and from allantoic fluid to blood. Same species as a 

 c Lysosomal activity in extra-embryonic membranes. Same species as a 

 SIM OLA, Ms. L. K.; Prof. - Dept. of Bot., Univ. of Helsinki, Unionkatu 44, 00170 HELSINKI 17, 



Finland 

 SIM ONI, A.; Dr.biol. - Inst, of Histol. and Embryol., Univ. of Pisa, Via A. Volta 4, 56100 PISA, Italy 

 a Immunochemical characterization of yolk precursors. Drosophila spec. (Diptera) 

 SIMONS, R. F. - A.R.C. Inst, of Anim. Physiol., Anim. Res. Station, 307 Huntingdon Rd., 



CAMBRIDGE CB3 OJQ, England 

 a In vitro maturation and in vivo and in vitro fertilization of oocytes; culture of embryos and 



preservation by deep freezing; development of a non-surgical method for recovery of embryos 



and the investigation of factors affecting the survival of embryos after non-surgical transfer; fac- 

 tors affecting twinning by egg transfer. Bos taurus (Artiodactyla) 

 b Methods for collection and transplantation of embryos; factors affecting the viability of embryos 



and the establishment of pregnancy following egg transfer, culture, storage and deep-freezing of 



embryos; manipulation of embryos in vitro and sex determination; maturation of oocytes in vitro; 



basic studies on early embryonic development. Sus scrofa domesticus (Artiodactyla) 

 SIMPSON, Ms. P.; D.Sc. - Centre de Genet. Molec. du C.N.R.S., 91190 GIF-sur-YVETTE, France 

 a Temperature-sensitive mutations blocking clone development in imaginal discs, including t.s. cell 



lethals and mutations affecting the rate of cell division. Drosophila melanogaster (Diptera) 

 SINDEN, R. E.; Ph.D. - Dept. of ZooL and Appl. Entomol., Imperial Coll., Field Station, SilwoodPark, 



ASCOT, Berks. SL5 7DE, England 

 a Cytology of gametogenesis and invasion mechanisms. Plasmodium spp. (Sporozoa) 

 SISTO DANEO, Ms. L. - Dept. of Human Anat., Univ. of Torino, Corso M.d'Azeglio 52, 10126 



TORINO, Italy 

 a Early neuro-muscular contacts in the heart. GaUus domesticus (Aves) 

 SKOBLINA, M. N. - N. K. Koltzov Inst, of Devi. Biol., USSR Acad, of Sci., Vavilov St 26, MOSCOW 



117334, U.S.S.R. 

 a Effect of gonadotropins on changes in the germinal vesicle and in the oocyte cytoplasm during 



maturation. (Acipenseridae,Chondrostei; Amphibia) 

 b Role of karyoplasm in the formation of the mature egg properties. Acipenser stellatus (Chon- 



drostei), Pleurodeles waltl (Urodela), Rana temporaria, Bufo spec. (Anura) 

 c Mechanism of action of gonadotropic hormones. Same species as b 

 §KREB, N.; M. D., D.Sc, Prof. - Inst, of Biol., Fac. of Med., Univ. of Zagreb, Salata 3, P.O.Box 166, 



41001 ZAGREB, Yugoslavia 

 a Early differentiation; transplantation, in vitro culture. Rattus norvegicus (Rodentia) (with 



B. LEVAK, L. HOFMAN, V. CRNEK and A. SVAJGER (Inst, of Histol. and Embryol.)) 

 b Analysis of soluble proteins in organogenesis, and of foetal proteins in differentiation. Same 



species as a (with D. SERMAN) 

 c Differentiation of early postimplantation stages under the kidney capsule, teratocarcinogenesis, 



nature of embryonal carcinoma cells; transplantation, electron microscopy. Mus musculus, 



Rattus norvegicus (Rodentia) (with V. CRNEK) , 



SLABt, O.; D.Sc, Prof. - Inst, of Histol. and Embryol., Charles Univ., Karlovarska 48, 30167 PLZLN, 



(^76p1i oslovulcis 

 a Development of the nasal capsule from an evolutionary standpoint. (Amniota, incl. Homo sapiens) 

 SLACK, J. M. W.; Ph.D. - Mill Hill Labs., Imp. Cane Res. Fund, Burtonhole Lane, LONDON NW7 

 IAD, England . ,,, . , x 



a Pattern formation in early mesoderm. Xenopus laevis (Anura), Ambystoma mexicanum (Urodela) 

 b Pattern formation in the developing and regenerating limb. Ambystoma mexicanum (Urodela) 

 SLADECEK, F.; RNDr., D.Sc, Prof. - Dept. of Exp. Zool., Charles Univ., Vinicna 7, 12844 PRAHA 2, 



Czechoslovakia 



103 



