S. M. Willadsen

5.3k total citations · 1 hit paper
56 papers, 3.4k citations indexed

About

S. M. Willadsen is a scholar working on Public Health, Environmental and Occupational Health, Genetics and Reproductive Medicine. According to data from OpenAlex, S. M. Willadsen has authored 56 papers receiving a total of 3.4k indexed citations (citations by other indexed papers that have themselves been cited), including 35 papers in Public Health, Environmental and Occupational Health, 17 papers in Genetics and 15 papers in Reproductive Medicine. Recurrent topics in S. M. Willadsen's work include Reproductive Biology and Fertility (35 papers), Sperm and Testicular Function (14 papers) and Pluripotent Stem Cells Research (9 papers). S. M. Willadsen is often cited by papers focused on Reproductive Biology and Fertility (35 papers), Sperm and Testicular Function (14 papers) and Pluripotent Stem Cells Research (9 papers). S. M. Willadsen collaborates with scholars based in United States, Slovakia and United Kingdom. S. M. Willadsen's co-authors include Jacques Cohen, Cécile Polge, L. E. A. ROWSON, Carole B. Fehilly, James J. Stachecki, R. M. Moor, Alan Trounson, J. Barritt, Carol A. Brenner and Elizabeth M. Tucker and has published in prestigious journals such as Nature, Development and Human Reproduction.

In The Last Decade

S. M. Willadsen

55 papers receiving 3.1k citations

Hit Papers

Nuclear transplantation in sheep embryos 1986 2026 1999 2012 1986 100 200 300 400 500
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. Nuclear transplantation in sheep embryos
    1986 523 citations S. M. Willadsen profile →

Peers

S. M. Willadsen
Mark Westhusin United States
Yvan Heyman France
G.B. Anderson United States
R.A. Godke United States
D. Rath Germany
Carol L. Keefer United States
U. Besenfelder Austria
Pilar Coy Spain
Thomas D. Bunch United States
N.M. Loskutoff United States
Mark Westhusin United States
S. M. Willadsen
Citations per year, relative to S. M. Willadsen S. M. Willadsen (= 1×) peers Mark Westhusin

Countries citing papers authored by S. M. Willadsen

Since Specialization
Citations

This map shows the geographic impact of S. M. Willadsen's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by S. M. Willadsen with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites S. M. Willadsen more than expected).

Fields of papers citing papers by S. M. Willadsen

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by S. M. Willadsen. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by S. M. Willadsen. The network helps show where S. M. Willadsen may publish in the future.

Co-authorship network of co-authors of S. M. Willadsen

This figure shows the co-authorship network connecting the top 25 collaborators of S. M. Willadsen. A scholar is included among the top collaborators of S. M. Willadsen based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with S. M. Willadsen. S. M. Willadsen is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Alikani, Mina, Tim Schimmel, & S. M. Willadsen. (2005). Cytoplasmic fragmentation in activated eggs occurs in the cytokinetic phase of the cell cycle, in lieu of normal cytokinesis, and in response to cytoskeletal disorder. Molecular Human Reproduction. 11(5). 335–344. 31 indexed citations
2.
Alikani, Mina & S. M. Willadsen. (2002). Human blastocysts from aggregated mononucleated cells of two or more non-viable zygote-derived embryos. Reproductive BioMedicine Online. 5(1). 56–58. 21 indexed citations
3.
Stachecki, James J., Jacques Cohen, Tim Schimmel, & S. M. Willadsen. (2002). Fetal development of mouse oocytes and zygotes cryopreserved in a nonconventional freezing medium. Cryobiology. 44(1). 5–13. 42 indexed citations
4.
Barritt, J., S. M. Willadsen, Carol A. Brenner, & Jacques Cohen. (2001). Cytoplasmic transfer in assisted reproduction. Human Reproduction Update. 7(4). 428–435. 115 indexed citations
5.
Willadsen, S. M., Jacob Levron, S. Munné, et al.. (1999). Rapid visualization of metaphase chromosomes in single human blastomeres after fusion with in-vitro matured bovine eggs. Human Reproduction. 14(2). 470–475. 64 indexed citations
6.
Stachecki, James J., Jacques Cohen, & S. M. Willadsen. (1998). Detrimental Effects of Sodium during Mouse Oocyte Cryopreservation. Biology of Reproduction. 59(2). 395–400. 84 indexed citations
7.
Stachecki, James J., Jacques Cohen, & S. M. Willadsen. (1998). Cryopreservation of Unfertilized Mouse Oocytes: The Effect of Replacing Sodium with Choline in the Freezing Medium. Cryobiology. 37(4). 346–354. 91 indexed citations
8.
Levron, Jacob, S. M. Willadsen, Massimo Bertoli, & Jacques Cohen. (1996). The development of mouse zygotes after fusion with synchronous and asynchronous cytoplasm. Human Reproduction. 11(6). 1287–1292. 36 indexed citations
9.
Levron, Jacob, S. Munné, S. M. Willadsen, Zev Rosenwaks, & Jacques Cohen. (1995). Male and Female Genomes Associated in a Single Pronucleus in Human Zygotes. Biology of Reproduction. 52(3). 653–657. 53 indexed citations
10.
Levron, Jacob, Jacques Cohen, & S. M. Willadsen. (1995). Highly effective method of human oocyte activation. Zygote. 3(2). 157–161. 13 indexed citations
11.
12.
Willadsen, S. M.. (1980). The viability of early cleavage stages containing half the normal number of blastomeres in the sheep. Reproduction. 59(2). 357–362. 83 indexed citations
13.
Willadsen, S. M. & Cécile Polge. (1980). Embryo transplantation in the large domestic species: applications and perspectives in the light of recent experiments with eggs and embryos.. 141. 115–126. 3 indexed citations
14.
Willadsen, S. M., Cécile Polge, & L. E. A. ROWSON. (1978). The viability of deep-frozen cow embryos. Reproduction. 52(2). 391–393. 68 indexed citations
15.
Trounson, Alan, S. M. Willadsen, & L. E. A. ROWSON. (1977). Fertilization and development capability of bovine follicular oocytes matured in vitro and in vivo and transferred to the oviducts of rabbits and cows. Reproduction. 51(2). 321–327. 70 indexed citations
16.
Trounson, Alan, S. M. Willadsen, & R. M. Moor. (1977). Reproductive function in prepubertal lambs: ovulation, embryo development and ovarian steroidogenesis. Reproduction. 49(1). 69–75. 21 indexed citations
17.
Willadsen, S. M.. (1977). Factors Affecting the Survival of Sheep Embryos during Deep‐Freezing and Thawing. Novartis Foundation symposium. 175–201. 99 indexed citations
18.
Trounson, Alan, S. M. Willadsen, & L. E. A. ROWSON. (1976). The influence of in-vitro culture and cooling on the survival and development of cow embryos. Reproduction. 47(2). 367–370. 54 indexed citations
19.
Willadsen, S. M., Cécile Polge, L. E. A. ROWSON, & R. M. Moor. (1976). Deep freezing of sheep embryos. Reproduction. 46(1). 151–154. 105 indexed citations
20.
Trounson, Alan, S. M. Willadsen, L. E. A. ROWSON, & Richard D. Newcomb. (1976). The storage of cow eggs at room temperature and at low temperatures. Reproduction. 46(1). 173–178. 50 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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