Shigeki Koyama

617 citations
33 papers · 461 indexed · h-index 12

Shigeki Koyama

32 papers receiving 445 citations

Peers

Shigeki Koyama
Comparison fields: 5 of 77
  • Gastroenterology 132
  • Surgery 236
  • Genetics 114
  • Nutrition and Dietetics 58
  • Internal Medicine 10
Replace Michael Yang with:
Michael Yang United States
M. Farbstein Israel
Chikako Tokoro Japan
Kenji Kozuka United States
Tomoaki Kono Japan
N Chopita Argentina
Toshio Yamada Japan
B M von Blomberg Netherlands
Shirley Paski United States
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Citations per field
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Citations per year

Countries citing papers authored by Shigeki Koyama

Since Specialization
Citations

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

Fields of papers citing papers by Shigeki Koyama

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

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

Co-authorship network

The 25 scholars most cited alongside Shigeki Koyama, linked wherever they have co-authored with each other. Click a name or a connecting line to browse the papers they share.

Border = papers with Shigeki Koyama Line = papers co-authored together Shigeki Koyama links everyone, so they are left out of the graph.

All Works

20 of 20 papers shown
#Work
1 200958
2 200591
3 200417
4 20041
5
[Histopathological examination in gastroesophageal reflux disease (GERD)].
20041
6 200315
7 200216
8 20028
9 200040
10 200027
11 20009
12 19982
13 199635
14 19944
15
A Clinical Experience of Inserting a Decompression Tube using a Colonoscope for Obstructive Left Colorectal Cancer
19933
16 19921
17 19921
18 19903
19 19865
20 19841

About Shigeki Koyama

Shigeki Koyama is a scholar working on Gastroenterology, Surgery, Genetics, Neurology and Otorhinolaryngology, having authored 33 papers that have together received 461 indexed citations. Recurring topics across this work include Inflammatory Bowel Disease (6 papers), Helicobacter pylori-related gastroenterology studies (5 papers), Esophageal Cancer Research and Treatment (4 papers), Microscopic Colitis (4 papers), Gastrointestinal motility and disorders (3 papers), Eosinophilic Esophagitis (3 papers), Gastrointestinal Tumor Research and Treatment (3 papers) and Gastroesophageal reflux and treatments (2 papers). The work is most often cited by research in Gastroenterology (132 citations), Surgery (236 citations), Genetics (114 citations), Nutrition and Dietetics (58 citations) and Internal Medicine (10 citations). Shigeki Koyama has collaborated with scholars based in Japan and United States. Frequent co-authors include Yoshihide Fujiyama, Akira Andoh, Tadao Bamba, Yoshio Araki, Masaya Sasaki, Tomoyuki Tsujikawa, Shigeki Bamba, Atsushi Ogawa, Osamu Kanauchi and Hisayuki Inoue. Their work appears in journals such as Journal of Gastroenterology and Hepatology, Journal of Gastroenterology, Digestive Endoscopy, Gastroenterology and Naunyn-Schmiedeberg s Archives of Pharmacology.

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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