Hiroyasu Oyama

628 total citations
11 papers, 465 citations indexed

About

Hiroyasu Oyama is a scholar working on Surgery, Rheumatology and Pulmonary and Respiratory Medicine. According to data from OpenAlex, Hiroyasu Oyama has authored 11 papers receiving a total of 465 indexed citations (citations by other indexed papers that have themselves been cited), including 10 papers in Surgery, 7 papers in Rheumatology and 2 papers in Pulmonary and Respiratory Medicine. Recurrent topics in Hiroyasu Oyama's work include Pancreatitis Pathology and Treatment (8 papers), IgG4-Related and Inflammatory Diseases (7 papers) and Gastrointestinal disorders and treatments (5 papers). Hiroyasu Oyama is often cited by papers focused on Pancreatitis Pathology and Treatment (8 papers), IgG4-Related and Inflammatory Diseases (7 papers) and Gastrointestinal disorders and treatments (5 papers). Hiroyasu Oyama collaborates with scholars based in Japan and United States. Hiroyasu Oyama's co-authors include Takayoshi Nishino, Keiko Shiratori, Fumitake Toki, Itaru Oi, Kyoko Shimizu, Makio Kobayashi, Ken Takasaki, Etsuko Hashimoto, Takashi Hatori and Shinichiro Watanabe and has published in prestigious journals such as Gastrointestinal Endoscopy, Journal of Gastroenterology and Pancreas.

In The Last Decade

Hiroyasu Oyama

10 papers receiving 442 citations

Peers — A (Enhanced Table)

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

Name h Career Trend Papers Cites
Hiroyasu Oyama Japan 8 442 401 238 38 35 11 465
Marcel Cazemier Netherlands 8 177 0.4× 117 0.3× 26 0.1× 9 0.2× 37 1.1× 8 250
Pablo Lozano Spain 8 103 0.2× 36 0.1× 25 0.1× 26 0.7× 11 0.3× 23 140
Nobuhito Sogawa Japan 6 209 0.5× 158 0.4× 56 0.2× 11 0.3× 61 1.7× 7 258
Attila Szepes Hungary 8 134 0.3× 29 0.1× 29 0.1× 77 2.0× 54 1.5× 35 165
Paul Skaife United Kingdom 6 77 0.2× 35 0.1× 19 0.1× 35 0.9× 39 1.1× 13 122
Vincenzo Maffettone Italy 9 249 0.6× 29 0.1× 15 0.1× 19 0.5× 25 0.7× 15 276
Ioannis Mamaloudis Greece 7 118 0.3× 16 0.0× 41 0.2× 23 0.6× 44 1.3× 19 171
M. Leela Prasad United States 7 296 0.7× 148 0.4× 16 0.1× 30 0.8× 161 4.6× 10 340
Dai Akiyama Japan 9 264 0.6× 44 0.1× 53 0.2× 197 5.2× 161 4.6× 17 296
A. Papazian France 7 124 0.3× 12 0.0× 126 0.5× 30 0.8× 12 0.3× 23 222

Countries citing papers authored by Hiroyasu Oyama

Since Specialization
Citations

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

Fields of papers citing papers by Hiroyasu Oyama

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

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

Co-authorship network of co-authors of Hiroyasu Oyama

This figure shows the co-authorship network connecting the top 25 collaborators of Hiroyasu Oyama. A scholar is included among the top collaborators of Hiroyasu Oyama 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 Hiroyasu Oyama. Hiroyasu Oyama is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

11 of 11 papers shown
1.
Nishino, Takayoshi, Hiroyasu Oyama, Fumitake Toki, & Keiko Shiratori. (2010). Differentiation between autoimmune pancreatitis and pancreatic carcinoma based on endoscopic retrograde cholangiopancreatography findings. Journal of Gastroenterology. 45(9). 988–996. 37 indexed citations
2.
Oyama, Hiroyasu, Kyoko Shimizu, Hiroyuki Konishi, et al.. (2010). Two case of pancreatic cancer with pseudocyst successfully treated by EUS-guided drainage. Progress of Digestive Endoscopy. 76(2). 122–123. 1 indexed citations
3.
Nishino, Takayoshi, Fumitake Toki, Hiroyasu Oyama, & Keiko Shiratori. (2008). MORE ACCURATE PREDICTION OF POST‐ERCP PANCREATITIS BY 4‐H SERUM LIPASE LEVELS THAN AMYLASE LEVELS. Digestive Endoscopy. 20(4). 169–177. 12 indexed citations
4.
Nishino, Takayoshi, Hiroyasu Oyama, Etsuko Hashimoto, et al.. (2007). Clinicopathological differentiation between sclerosing cholangitis with autoimmune pancreatitis and primary sclerosing cholangitis. Journal of Gastroenterology. 42(7). 550–559. 79 indexed citations
5.
Nishino, Takayoshi, Fumitake Toki, Itaru Oi, et al.. (2006). Prevalence of pancreatic and biliary tract tumors in pancreas divisum. Journal of Gastroenterology. 41(11). 1088–1093. 16 indexed citations
6.
Nishino, Takayoshi, Fumitake Toki, Hiroyasu Oyama, et al.. (2006). Long-Term Outcome of Autoimmune Pancreatitis After Oral Prednisolone Therapy. Gastrointestinal Endoscopy. 63(5). AB311–AB311. 39 indexed citations
7.
Nishino, Takayoshi, Etsuko Hashimoto, Fumitake Toki, et al.. (2006). Clinicopathological Differentiation Between Primary Sclerosing Cholangitis and Sclerosing Cholangitis with Autoimmune Pancreatitis. Gastrointestinal Endoscopy. 63(5). AB306–AB306.
8.
Nishino, Takayoshi, Fumitake Toki, Hiroyasu Oyama, Kyoko Shimizu, & Keiko Shiratori. (2006). Long-term Outcome of Autoimmune Pancreatitis after Oral Prednisolone Therapy. Internal Medicine. 45(8). 497–501. 134 indexed citations
9.
Nishino, Takayoshi, Fumitake Toki, Hiroyasu Oyama, et al.. (2005). Biliary tract involvement in autoimmune pancreatitis.. PubMed. 30(1). 76–82. 132 indexed citations
10.
Nishino, Takayoshi, Fumitake Toki, Keiko Shiratori, Itaru Oi, & Hiroyasu Oyama. (2005). EFFICACY AND ISSUES RELATED TO PREDNISOLONE THERAPY OF AUTOIMMUNE PANCREATITIS. Pancreas. 31(1). 1–1. 3 indexed citations
11.
Nishino, Takayoshi, et al.. (1999). An Endothelial Nitric Oxide Synthase Inhibitor Aggravates CDL-Induced Acute Pancreatitis in Rats. Pancreas. 19(4). 390–400. 12 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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