Ken Okai

753 total citations
39 papers, 547 citations indexed

About

Ken Okai is a scholar working on Hepatology, Epidemiology and Surgery. According to data from OpenAlex, Ken Okai has authored 39 papers receiving a total of 547 indexed citations (citations by other indexed papers that have themselves been cited), including 26 papers in Hepatology, 21 papers in Epidemiology and 6 papers in Surgery. Recurrent topics in Ken Okai's work include Liver Disease Diagnosis and Treatment (19 papers), Liver Diseases and Immunity (15 papers) and Liver Disease and Transplantation (8 papers). Ken Okai is often cited by papers focused on Liver Disease Diagnosis and Treatment (19 papers), Liver Diseases and Immunity (15 papers) and Liver Disease and Transplantation (8 papers). Ken Okai collaborates with scholars based in Japan and China. Ken Okai's co-authors include Hiromasa Ohira, Atsushi Takahashi, Kazumichi Abe, Manabu Hayashi, Masashi Fujita, Hiromichi Imaizumi, Yukiko Kanno, Kyoko Monoe, Hiroshi Watanabe and Hironobu Saito and has published in prestigious journals such as PLoS ONE, Journal of Hepatology and Microbiology.

In The Last Decade

Ken Okai

38 papers receiving 539 citations

Peers — A (Enhanced Table)

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

Name h Career Trend Papers Cites
Ken Okai Japan 13 285 253 117 94 91 39 547
Takumi Aramaki Japan 15 191 0.7× 277 1.1× 49 0.4× 97 1.0× 218 2.4× 77 638
Kenji Kowatari Japan 9 181 0.6× 134 0.5× 131 1.1× 32 0.3× 72 0.8× 13 576
Nary Veal France 13 315 1.1× 250 1.0× 27 0.2× 73 0.8× 112 1.2× 22 510
Eddie Island United States 20 163 0.6× 318 1.3× 109 0.9× 239 2.5× 583 6.4× 56 1.2k
Mounif El‐Youssef United States 20 362 1.3× 120 0.5× 61 0.5× 253 2.7× 495 5.4× 34 1.2k
Nevin Oruç Türkiye 14 178 0.6× 62 0.2× 62 0.5× 57 0.6× 274 3.0× 62 555
Masaaki Hirata Japan 9 89 0.3× 133 0.5× 186 1.6× 56 0.6× 187 2.1× 40 524
Jens Peter Gøtze Denmark 17 128 0.4× 87 0.3× 42 0.4× 138 1.5× 141 1.5× 43 636
Joan Toscá Spain 14 221 0.8× 161 0.6× 23 0.2× 81 0.9× 224 2.5× 39 574
Rebecca Wilcox United States 11 105 0.4× 61 0.2× 50 0.4× 93 1.0× 219 2.4× 35 507

Countries citing papers authored by Ken Okai

Since Specialization
Citations

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

Fields of papers citing papers by Ken Okai

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

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

Co-authorship network of co-authors of Ken Okai

This figure shows the co-authorship network connecting the top 25 collaborators of Ken Okai. A scholar is included among the top collaborators of Ken Okai 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 Ken Okai. Ken Okai 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.
Takahashi, Atsushi, Kazumichi Abe, Masashi Fujita, et al.. (2020). Simple resistance exercise decreases cytokeratin 18 and fibroblast growth factor 21 levels in patients with nonalcoholic fatty liver disease. Medicine. 99(22). e20399–e20399. 24 indexed citations
2.
Fujita, Masashi, Ken Okai, Manabu Hayashi, et al.. (2019). Huge Hepatocellular Carcinoma Treated with Radical Hepatectomy after Drug-eluting Bead Transarterial Chemoembolization. Internal Medicine. 58(8). 1103–1110. 2 indexed citations
3.
Abe, Kazumichi, Atsushi Takahashi, Masashi Fujita, et al.. (2019). Interleukin‐33/ST2‐Mediated Inflammation Plays a Critical Role in the Pathogenesis and Severity of Type I Autoimmune Hepatitis. Hepatology Communications. 3(5). 670–684. 13 indexed citations
4.
Okai, Ken, Naoki Ichikawa‐Tomikawa, Akira Saitō, et al.. (2018). A novel occludin-targeting monoclonal antibody prevents hepatitis C virus infection in vitro. Oncotarget. 9(24). 16588–16598. 10 indexed citations
5.
Hayashi, Manabu, Kazumichi Abe, Naoki Matsuoka, et al.. (2018). Contrast uptake in primary hepatic angiosarcoma on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging in the hepatobiliary phase. World Journal of Hepatology. 10(1). 166–171. 1 indexed citations
6.
Abe, Kazumichi, Atsushi Takahashi, Masashi Fujita, et al.. (2018). Dysbiosis of oral microbiota and its association with salivary immunological biomarkers in autoimmune liver disease. PLoS ONE. 13(7). e0198757–e0198757. 80 indexed citations
7.
Hayashi, Manabu, Kazumichi Abe, Masashi Fujita, et al.. (2018). Serum levels of a cell death biomarker predict the development of cirrhosis-related conditions in primary biliary cholangitis. Medical Molecular Morphology. 51(3). 176–185. 7 indexed citations
8.
Takahashi, Atsushi, Hiromichi Imaizumi, Manabu Hayashi, et al.. (2017). Simple Resistance Exercise for 24 Weeks Decreases Alanine Aminotransferase Levels in Patients with Non-Alcoholic Fatty Liver Disease. PubMed. 1(1). E2–E7. 14 indexed citations
9.
Takahashi, Atsushi, Akira Wada, Kazumichi Abe, et al.. (2017). Reduced brain activity in female patients with non-alcoholic fatty liver disease as measured by near-infrared spectroscopy. PLoS ONE. 12(4). e0174169–e0174169. 31 indexed citations
10.
Fujita, Masashi, Kazumichi Abe, Manabu Hayashi, et al.. (2017). Two cases of liver cirrhosis treated with lusutrombopag before partial splenic embolization. FUKUSHIMA JOURNAL OF MEDICAL SCIENCE. 63(3). 165–171. 6 indexed citations
11.
Abe, Kazumichi, Atsushi Takahashi, Hiromichi Imaizumi, et al.. (2016). Interleukin-21 plays a critical role in the pathogenesis and severity of type I autoimmune hepatitis. SpringerPlus. 5(1). 777–777. 28 indexed citations
12.
Hayashi, Manabu, Kazumichi Abe, Hiromichi Imaizumi, et al.. (2016). Drug-induced liver injury with autoimmune features complicated with hemophagocytic syndrome. Clinical Journal of Gastroenterology. 9(3). 150–155. 6 indexed citations
13.
Okai, Ken, Kaoru Sakurai, Hiroyuki Terawaki, et al.. (2015). Autologous blood transfusion for hemodialysis patients: A case report and review of clinical reports and therapeutic features. Transfusion and Apheresis Science. 52(2). 204–207. 1 indexed citations
14.
Fujita, Masashi, Atsushi Takahashi, Hiromichi Imaizumi, et al.. (2015). Drug-induced Liver Injury with HHV-6 Reactivation. Internal Medicine. 54(10). 1219–1222. 5 indexed citations
15.
Abe, Kazumichi, Atsushi Takahashi, Yoshihiro Nozawa, et al.. (2014). The utility of IgG, IgM, and CD138 immunohistochemistry in the evaluation of autoimmune liver diseases. Medical Molecular Morphology. 47(3). 162–168. 9 indexed citations
16.
Okai, Ken, Osamu Ichii, Masahiro Yamasaki, et al.. (2013). A case of acute-onset autoimmune hepatitis that showed false positive for IgM-HA antibody. Kanzo. 54(1). 27–32. 1 indexed citations
17.
Takahashi, Atsushi, Kazumichi Abe, Rie Saito, et al.. (2013). Liver Dysfunction in Patients with Systemic Lupus Erythematosus. Internal Medicine. 52(13). 1461–1465. 57 indexed citations
18.
Saito, Hironobu, Atsushi Takahashi, Kazumichi Abe, et al.. (2012). AUTOANTIBODIES BY LINE IMMUNOASSAY IN PATIENTS WITH PRIMARY BILIARY CIRRHOSIS. FUKUSHIMA JOURNAL OF MEDICAL SCIENCE. 58(2). 107–116. 30 indexed citations
19.
Koyama, Yoshimasa, Tohru Kodama, Kazumi Takahashi, Ken Okai, & Yukihiko Kayama. (2002). Firing properties of neurones in the laterodorsal hypothalamic area during sleep and wakefulness. Psychiatry and Clinical Neurosciences. 56(3). 339–340. 6 indexed citations
20.
Okai, Ken, et al.. (1999). [Complications of extraintestinal endocrine disease associated with ulcerative colitis--association of ulcerative colitis and autoimmune thyroid disease].. PubMed. 57(11). 2536–9. 4 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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