Masayasu Koyama

2.8k total citations
122 papers, 2.0k citations indexed

About

Masayasu Koyama is a scholar working on Immunology, Surgery and Obstetrics and Gynecology. According to data from OpenAlex, Masayasu Koyama has authored 122 papers receiving a total of 2.0k indexed citations (citations by other indexed papers that have themselves been cited), including 32 papers in Immunology, 29 papers in Surgery and 27 papers in Obstetrics and Gynecology. Recurrent topics in Masayasu Koyama's work include Reproductive System and Pregnancy (26 papers), Pelvic floor disorders treatments (23 papers) and Pregnancy and preeclampsia studies (21 papers). Masayasu Koyama is often cited by papers focused on Reproductive System and Pregnancy (26 papers), Pelvic floor disorders treatments (23 papers) and Pregnancy and preeclampsia studies (21 papers). Masayasu Koyama collaborates with scholars based in Japan, United States and Germany. Masayasu Koyama's co-authors include Fumitaka Saji, Chihiro Azuma, Noboru Matsuzaki, Koichiro Shimoya, Yuji Murata, Hitomi Nakamura, Kazuhide Ogita, Tadashi Kimura, Osamu Tanizawa and Takashi Kameda and has published in prestigious journals such as Scientific Reports, Biochemical and Biophysical Research Communications and FEBS Letters.

In The Last Decade

Masayasu Koyama

117 papers receiving 2.0k citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Masayasu Koyama Japan 22 654 430 380 321 309 122 2.0k
Chihiro Azuma Japan 26 1.1k 1.7× 375 0.9× 399 1.1× 161 0.5× 92 0.3× 75 2.9k
Koichiro Shimoya Japan 27 639 1.0× 442 1.0× 482 1.3× 329 1.0× 212 0.7× 114 2.2k
Ermelando V. Cosmi Italy 25 179 0.3× 511 1.2× 265 0.7× 315 1.0× 331 1.1× 115 2.0k
T. Chard United Kingdom 27 420 0.6× 777 1.8× 351 0.9× 192 0.6× 195 0.6× 118 2.7k
Christian J. Thaler Germany 32 670 1.0× 567 1.3× 767 2.0× 229 0.7× 175 0.6× 148 2.9k
Vasso Terzidou United Kingdom 25 494 0.8× 400 0.9× 487 1.3× 924 2.9× 59 0.2× 51 1.8k
Simon C. Riley United Kingdom 36 715 1.1× 807 1.9× 974 2.6× 536 1.7× 276 0.9× 103 3.9k
Laura T. Goldsmith United States 30 555 0.8× 561 1.3× 1.5k 4.0× 330 1.0× 326 1.1× 93 2.8k
Oksana Shynlova Canada 31 1.5k 2.3× 887 2.1× 1.0k 2.7× 1.3k 4.2× 257 0.8× 79 3.1k
Harald Abele Germany 27 174 0.3× 631 1.5× 392 1.0× 268 0.8× 526 1.7× 182 2.5k

Countries citing papers authored by Masayasu Koyama

Since Specialization
Citations

This map shows the geographic impact of Masayasu Koyama'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 Masayasu Koyama with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Masayasu Koyama more than expected).

Fields of papers citing papers by Masayasu Koyama

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Masayasu Koyama. 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 Masayasu Koyama. The network helps show where Masayasu Koyama may publish in the future.

Co-authorship network of co-authors of Masayasu Koyama

This figure shows the co-authorship network connecting the top 25 collaborators of Masayasu Koyama. A scholar is included among the top collaborators of Masayasu Koyama 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 Masayasu Koyama. Masayasu Koyama 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
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Santostefano, Katherine E., Coy D. Heldermon, Daisuke Tachibana, et al.. (2020). Generation of Induced Pluripotent Stem Cells from a Female Patient with a Xq27.3-q28 Deletion to Establish Disease Models and Identify Therapies. Cellular Reprogramming. 22(4). 179–188. 4 indexed citations
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Kato, Kumiko, et al.. (2020). Techniques of transvaginal mesh prolapse surgery in Japan, and the comparison of complication rates by surgeons’ specialty and experience. International Journal of Urology. 27(11). 996–1000. 16 indexed citations
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Nakagawa, Tomoko, et al.. (2015). A Case of Fetal Intestinal Volvulus without Malrotation Causing Severe Anemia. PubMed. 6. 1–3. 8 indexed citations
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Fukuda, Takeshi, et al.. (2012). Outcomes of traditional prolapse surgery for pelvic organ prolapse repair at a single center. International Journal of Gynecology & Obstetrics. 119(3). 277–280. 2 indexed citations
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Nagata, Ichiro, Gen Murakami, Daisuke Suzuki, et al.. (2007). Histological features of the rectovaginal septum in elderly women and a proposal for posterior vaginal defect repair. International Urogynecology Journal. 18(8). 863–868. 21 indexed citations
9.
Nakamura, Hitomi, Tadashi Kimura, Shinsuke Koyama, et al.. (2006). Mouse model of human infertility: Transient and local inhibition of endometrial STAT‐3 activation results in implantation failure. FEBS Letters. 580(11). 2717–2722. 60 indexed citations
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Koyama, Shinsuke, Tadashi Kimura, Kazuhide Ogita, et al.. (2006). Simple and highly efficient method for transient in vivo gene transfer to mid-late pregnant mouse uterus. Journal of Reproductive Immunology. 70(1-2). 59–69. 10 indexed citations
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Miyoshi, Eiji, Naoyuki Taniguchi, Tadashi Kimura, et al.. (2005). Elevated expression of N-acetylglucosaminyltransferase V in first trimester human placenta. Biochemical and Biophysical Research Communications. 330(3). 999–1004. 15 indexed citations
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Koyama, Shinsuke, Tadashi Kimura, Yoshihiro Tokugawa, et al.. (2005). Occurrence of fetal choroid plexus cysts in siblings: Concerns regarding recurrence and chromosomal abnormality. Journal of obstetrics and gynaecology research. 31(6). 562–564. 2 indexed citations
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Shiki, Yasuhiko, Koichiro Shimoya, Yoshihiro Tokugawa, et al.. (2004). Changes of lipocalin‐type prostaglandin D synthase level during pregnancy. Journal of obstetrics and gynaecology research. 30(1). 65–70. 16 indexed citations
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Sawai, Keisuke, Shoji Kamiura, Masayasu Koyama, et al.. (2002). Expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase in cervical intraepithelial neoplasia. International Journal of Oncology. 21(2). 281–7. 8 indexed citations
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Nakamura, Hitomi, Tadashi Kimura, Atsuko Nakajima, et al.. (2002). Detection of oxidative stress in seminal plasma and fractionated sperm from subfertile male patients. European Journal of Obstetrics & Gynecology and Reproductive Biology. 105(2). 155–160. 39 indexed citations
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Azuma, Chihiro, et al.. (1995). Interleukin‐1 receptor antagonist expression in epithelial cells of human endometrium. International Journal of Gynecology & Obstetrics. 49(3). 305–310. 10 indexed citations
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Koyama, Masayasu, et al.. (1991). Probabilistic assessment of the HLA sharing of recurrent spontaneous abortion couples in the Japanese population. Tissue Antigens. 37(5). 211–217. 16 indexed citations
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Koyama, Masayasu, et al.. (1991). Differential mRNA expression of three distinct classes of Fcγ receptor at the feto-maternal interface. Journal of Reproductive Immunology. 20(2). 103–113. 19 indexed citations
20.
Kameda, Takashi, et al.. (1991). Localization of three subtypes of Fcγ receptors in human placenta by immunohistochemical analysis. Placenta. 12(1). 15–26. 63 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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