Keisuke Koyama

489 total citations
34 papers, 346 citations indexed

About

Keisuke Koyama is a scholar working on Public Health, Environmental and Occupational Health, Reproductive Medicine and Agronomy and Crop Science. According to data from OpenAlex, Keisuke Koyama has authored 34 papers receiving a total of 346 indexed citations (citations by other indexed papers that have themselves been cited), including 15 papers in Public Health, Environmental and Occupational Health, 10 papers in Reproductive Medicine and 9 papers in Agronomy and Crop Science. Recurrent topics in Keisuke Koyama's work include Reproductive Biology and Fertility (15 papers), Reproductive Physiology in Livestock (9 papers) and Sperm and Testicular Function (9 papers). Keisuke Koyama is often cited by papers focused on Reproductive Biology and Fertility (15 papers), Reproductive Physiology in Livestock (9 papers) and Sperm and Testicular Function (9 papers). Keisuke Koyama collaborates with scholars based in Japan, Germany and United States. Keisuke Koyama's co-authors include Masashi Nagano, Yoshiyuki Takahashi, Yojiro Yanagawa, Sung-Sik Kang, Weiping Huang, Hiroshi Takano, Y. Tsunoda, A. Hasegawa, Nancy J. Alexander and M. Inoue and has published in prestigious journals such as Journal of Allergy and Clinical Immunology, Journal of Dairy Science and Human Reproduction.

In The Last Decade

Keisuke Koyama

33 papers receiving 337 citations

Peers — A (Enhanced Table)

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

Name h Career Trend Papers Cites
Keisuke Koyama Japan 11 171 128 94 76 60 34 346
Joabel Tonellotto dos Santos Brazil 10 173 1.0× 89 0.7× 143 1.5× 84 1.1× 59 1.0× 28 345
F.M. Rodríguez Argentina 14 171 1.0× 77 0.6× 239 2.5× 99 1.3× 63 1.1× 20 408
M Pinto Chile 6 174 1.0× 128 1.0× 119 1.3× 34 0.4× 50 0.8× 9 387
Suocheng Wei China 11 99 0.6× 101 0.8× 67 0.7× 99 1.3× 82 1.4× 58 334
J. M. Palomino Canada 10 111 0.6× 74 0.6× 90 1.0× 190 2.5× 61 1.0× 30 462
Carol J. Belfiore United States 8 80 0.5× 47 0.4× 197 2.1× 108 1.4× 31 0.5× 13 312
H. J. Howard United States 14 233 1.4× 58 0.5× 329 3.5× 187 2.5× 88 1.5× 22 611
Estelle Watson United Kingdom 12 84 0.5× 57 0.4× 346 3.7× 90 1.2× 67 1.1× 27 575
Vijay Simha Baddela Germany 10 95 0.6× 39 0.3× 95 1.0× 69 0.9× 146 2.4× 19 342
Maud Caillaud France 11 274 1.6× 248 1.9× 126 1.3× 54 0.7× 76 1.3× 12 425

Countries citing papers authored by Keisuke Koyama

Since Specialization
Citations

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

Fields of papers citing papers by Keisuke Koyama

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

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

Co-authorship network of co-authors of Keisuke Koyama

This figure shows the co-authorship network connecting the top 25 collaborators of Keisuke Koyama. A scholar is included among the top collaborators of Keisuke 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 Keisuke Koyama. Keisuke 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
1.
2.
Koyama, Keisuke, et al.. (2023). Parity affects the relationship between the insemination–ovulation interval and the conception rate in lactating dairy cows. Reproduction in Domestic Animals. 58(7). 895–902. 3 indexed citations
3.
Kawahara‐Miki, Ryouka, et al.. (2021). Impaired placentomal interferon signaling as the possible cause of retained fetal membrane in parturition-induced cows. Journal of Reproduction and Development. 68(1). 30–37. 1 indexed citations
4.
Higaki, Shogo, Keisuke Koyama, Yosuke Sasaki, et al.. (2020). Technical note: Calving prediction in dairy cattle based on continuous measurements of ventral tail base skin temperature using supervised machine learning. Journal of Dairy Science. 103(9). 8535–8540. 16 indexed citations
5.
Koyama, Keisuke, Ryosuke Sakumoto, Takashi Fujii, et al.. (2019). Enhanced glucocorticoid exposure facilitates the expression of genes involved in prostaglandin and estrogen syntheses in bovine placentomes at induced parturition. Theriogenology. 139. 1–7. 4 indexed citations
6.
Hirayama, Hiroki, Ryosuke Sakumoto, Keisuke Koyama, et al.. (2019). Expression of C–C motif chemokines and their receptors in bovine placentomes at spontaneous and induced parturition. Journal of Reproduction and Development. 66(1). 49–55. 4 indexed citations
7.
Nakamura, Kenji, Keisuke Koyama, Kengo Takeuchi, et al.. (2019). An increase in the deoxygenated hemoglobin concentration induced by a working memory task during the refractory period in the hemodynamic response in the human cerebral cortex. Neuroscience Letters. 714. 134531–134531. 6 indexed citations
8.
Koyama, Keisuke, Toshiyuki Suzuki, Ahmed Z. Balboula, et al.. (2018). Hot topic: Pregnancy-induced expression of interferon-stimulated genes in the cervical and vaginal mucosal membranes. Journal of Dairy Science. 101(9). 8396–8400. 21 indexed citations
9.
Koyama, Keisuke, et al.. (2017). Characteristics of dairy cows with a pronounced reduction in first milk yield after estrus onset. Jūigaku kenkyū/Japanese journal of veterinary research. 65(2). 55–63. 3 indexed citations
10.
Osawa, Yoko, et al.. (2017). Posterior Reversible Encephalopathy Syndrome after Lenvatinib Therapy in a Patient with Anaplastic Thyroid Carcinoma. Internal Medicine. 57(7). 1015–1019. 11 indexed citations
11.
Higaki, Shogo, Keisuke Koyama, Masashi Nagano, et al.. (2016). Early germinal vesicle breakdown is a predictor of high preimplantation developmental competent oocytes in mice. Zygote. 25(1). 41–48. 7 indexed citations
12.
Hirayama, Hiroki, Keisuke Koyama, Ken Sawai, et al.. (2015). Localization of TGF-β and TGF-β receptor in bovine term placentome and expression differences between spontaneous and induced parturition. Placenta. 36(11). 1239–1245. 10 indexed citations
13.
Yanagawa, Yojiro, Yoshiyuki Takahashi, Seiji Katagiri, et al.. (2014). Effects of ovarian storage condition on in vitro maturation of Hokkaido sika deer (Cervus nippon yesoensis) oocytes.. Hokkaido University Collection of Scholarly and Academic Papers (Hokkaido University). 62(4). 187–92. 6 indexed citations
14.
Hirayama, Hiroki, Satoru Moriyasu, Soichi KAGEYAMA, et al.. (2014). Enhancement of maternal recognition of pregnancy with parthenogenetic embryos in bovine embryo transfer. Theriogenology. 81(8). 1108–1115. 17 indexed citations
15.
Kang, Sung-Sik, Keisuke Koyama, Weiping Huang, et al.. (2014). Addition of D-penicillamine, hypotaurine, and epinephrine (PHE) mixture to IVF medium maintains motility and longevity of bovine sperm and enhances stable production of blastocysts <i>in vitro</i>. Journal of Reproduction and Development. 61(2). 99–105. 25 indexed citations
16.
17.
Koyama, Keisuke, Sung-Sik Kang, Weiping Huang, et al.. (2014). Aging-related Changes in <i>In Vitro</i>-matured Bovine Oocytes: Oxidative Stress, Mitochondrial Activity and ATP Content After Nuclear Maturation. Journal of Reproduction and Development. 60(2). 136–142. 44 indexed citations
18.
Nagano, Masashi, Sung-Sik Kang, Keisuke Koyama, et al.. (2013). In vitro maturation system for individual culture of bovine oocytes using micro-volume multi-well plate.. PubMed. 61(4). 149–54. 19 indexed citations
19.
Gosau, Martin, et al.. (2011). Frakturen von Maxilla und Mandibula. HNO. 59(11). 1079–1087. 3 indexed citations
20.
Takano, Hiroshi, et al.. (1993). Effect of aging of recipient oocytes on the development of bovine nuclear transfer embryos in vitro. Theriogenology. 39(4). 909–917. 23 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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