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Koichi Hirai

Koichi Hirai

D-Index & Metrics

Discipline name D-Index World Ranking National Ranking Publications Citations
Immunology 56 3760 148 167 8938

Koichi Hirai publications per year

The chart shows the history of publications by Koichi Hirai between 1965 and 2025, highlighting the no. of papers published in each year and offering an overview of the publication velocity of this scholar. Koichi Hirai published across 61 years, from 1965 to 2025, averaging 4 papers a year. Output peaked at 20 publications in 2000. 4 of the 244 publications appeared in the last two years.

No. of publications
5 10 15 20
Bar chart. Horizontal axis: year, 1965 to 2025. Vertical axis: number of publications, 0 to 20. Peak 20 publications in 2000. 1965: 1 publication 1966: 1 publication 1967: 2 publications 1968: 0 publications 1969: 2 publications 1970: 1 publication 1971: 4 publications 1972: 5 publications 1973: 3 publications 1974: 3 publications 1975: 0 publications 1976: 3 publications 1977: 2 publications 1978: 2 publications 1979: 1 publication 1980: 4 publications 1981: 3 publications 1982: 5 publications 1983: 7 publications 1984: 3 publications 1985: 6 publications 1986: 8 publications 1987: 5 publications 1988: 3 publications 1989: 5 publications 1990: 3 publications 1991: 4 publications 1992: 10 publications 1993: 14 publications 1994: 9 publications 1995: 8 publications 1996: 7 publications 1997: 5 publications 1998: 7 publications 1999: 13 publications 2000: 20 publications 2001: 12 publications 2002: 19 publications 2003: 10 publications 2004: 9 publications 2005: 6 publications 2006: 3 publications 2007: 1 publication 2008: 0 publications 2009: 1 publication 2010: 0 publications 2011: 0 publications 2012: 0 publications 2013: 0 publications 2014: 0 publications 2015: 0 publications 2016: 0 publications 2017: 0 publications 2018: 0 publications 2019: 0 publications 2020: 0 publications 2021: 0 publications 2022: 0 publications 2023: 0 publications 2024: 1 publication 2025: 3 publications
1965 2025

244 publications in total across all disciplines

View publications per year as a table
Koichi Hirai: publications per year, 1965 to 2025
Year Publications
1965 1
1966 1
1967 2
1968 0
1969 2
1970 1
1971 4
1972 5
1973 3
1974 3
1975 0
1976 3
1977 2
1978 2
1979 1
1980 4
1981 3
1982 5
1983 7
1984 3
1985 6
1986 8
1987 5
1988 3
1989 5
1990 3
1991 4
1992 10
1993 14
1994 9
1995 8
1996 7
1997 5
1998 7
1999 13
2000 20
2001 12
2002 19
2003 10
2004 9
2005 6
2006 3
2007 1
2008 0
2009 1
2010 0
2011 0
2012 0
2013 0
2014 0
2015 0
2016 0
2017 0
2018 0
2019 0
2020 0
2021 0
2022 0
2023 0
2024 1
2025 3
Total 244
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Koichi Hirai publication distribution in Immunology in 2026

The chart shows the distribution of publications by all Research.com ranked scientists in the field of Immunology in 2026. The highlighted bar marks where Koichi Hirai sits on this spectrum.

No. of scientists
50 100 150
Bar chart with 76 bars. Horizontal axis: publications, 62–71 to 807+. Vertical axis: number of scientists, 0 to 189. Most scientists, 189, have 152–161 publications. The last bar groups every scientist with 807 publications or more. The highlighted bar, 162–171 publications, is where this scientist sits. 62–71 publications: 9 scientists 72–81 publications: 23 scientists 82–91 publications: 40 scientists 92–101 publications: 72 scientists 102–111 publications: 86 scientists 112–121 publications: 108 scientists 122–131 publications: 150 scientists 132–141 publications: 160 scientists 142–151 publications: 159 scientists 152–161 publications: 189 scientists 162–171 publications: 166 scientists 172–181 publications: 181 scientists 182–191 publications: 188 scientists 192–201 publications: 187 scientists 202–211 publications: 178 scientists 212–221 publications: 158 scientists 222–231 publications: 168 scientists 232–241 publications: 159 scientists 242–251 publications: 160 scientists 252–261 publications: 148 scientists 262–271 publications: 116 scientists 272–281 publications: 125 scientists 282–291 publications: 115 scientists 292–301 publications: 111 scientists 302–311 publications: 95 scientists 312–321 publications: 97 scientists 322–331 publications: 97 scientists 332–341 publications: 99 scientists 342–351 publications: 96 scientists 352–361 publications: 69 scientists 362–371 publications: 76 scientists 372–381 publications: 71 scientists 382–391 publications: 71 scientists 392–401 publications: 62 scientists 402–411 publications: 54 scientists 412–421 publications: 41 scientists 422–431 publications: 63 scientists 432–441 publications: 53 scientists 442–451 publications: 31 scientists 452–461 publications: 42 scientists 462–471 publications: 40 scientists 472–481 publications: 29 scientists 482–491 publications: 34 scientists 492–501 publications: 30 scientists 502–511 publications: 23 scientists 512–521 publications: 41 scientists 522–531 publications: 29 scientists 532–541 publications: 28 scientists 542–551 publications: 16 scientists 552–561 publications: 18 scientists 562–571 publications: 18 scientists 572–581 publications: 17 scientists 582–591 publications: 17 scientists 592–601 publications: 17 scientists 602–611 publications: 19 scientists 612–621 publications: 13 scientists 622–631 publications: 12 scientists 632–641 publications: 11 scientists 642–651 publications: 16 scientists 652–661 publications: 9 scientists 662–671 publications: 5 scientists 672–681 publications: 13 scientists 682–691 publications: 12 scientists 692–701 publications: 6 scientists 702–711 publications: 6 scientists 712–721 publications: 9 scientists 722–731 publications: 9 scientists 732–741 publications: 6 scientists 742–751 publications: 11 scientists 752–761 publications: 10 scientists 762–771 publications: 7 scientists 772–781 publications: 12 scientists 782–791 publications: 7 scientists 792–801 publications: 5 scientists 802–806 publications: 1 scientist 807+ publications: 100 scientists
62–71 publications 807+

This scientist: 167 publications — 22nd percentile

22% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 807 publications or more.

View publications distribution as a table
Number of Immunology scientists by publication count, Research.com 2026 ranking edition. Based on 4,929 ranked scientists.
Publications Scientists This scientist
62–71 9
72–81 23
82–91 40
92–101 72
102–111 86
112–121 108
122–131 150
132–141 160
142–151 159
152–161 189
162–171 166 167
172–181 181
182–191 188
192–201 187
202–211 178
212–221 158
222–231 168
232–241 159
242–251 160
252–261 148
262–271 116
272–281 125
282–291 115
292–301 111
302–311 95
312–321 97
322–331 97
332–341 99
342–351 96
352–361 69
362–371 76
372–381 71
382–391 71
392–401 62
402–411 54
412–421 41
422–431 63
432–441 53
442–451 31
452–461 42
462–471 40
472–481 29
482–491 34
492–501 30
502–511 23
512–521 41
522–531 29
532–541 28
542–551 16
552–561 18
562–571 18
572–581 17
582–591 17
592–601 17
602–611 19
612–621 13
622–631 12
632–641 11
642–651 16
652–661 9
662–671 5
672–681 13
682–691 12
692–701 6
702–711 6
712–721 9
722–731 9
732–741 6
742–751 11
752–761 10
762–771 7
772–781 12
782–791 7
792–801 5
802–806 1
807+ 100
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Koichi Hirai D-index placement in Immunology in 2026

The chart shows the D-index (discipline H-index) distribution of Immunology scientists ranked by Research.com in 2026. The highlighted bar marks where Koichi Hirai sits on this spectrum.

No. of scientists
50 100 150 200
Bar chart with 60 bars. Horizontal axis: D-Index, 40–41 to 157+. Vertical axis: number of scientists, 0 to 201. Most scientists, 201, have 58–59 D-Index. The last bar groups every scientist with 157 D-Index or more. The highlighted bar, 56–57 D-Index, is where this scientist sits. 40–41 D-Index: 28 scientists 42–43 D-Index: 91 scientists 44–45 D-Index: 157 scientists 46–47 D-Index: 192 scientists 48–49 D-Index: 175 scientists 50–51 D-Index: 188 scientists 52–53 D-Index: 177 scientists 54–55 D-Index: 155 scientists 56–57 D-Index: 194 scientists 58–59 D-Index: 201 scientists 60–61 D-Index: 197 scientists 62–63 D-Index: 201 scientists 64–65 D-Index: 173 scientists 66–67 D-Index: 167 scientists 68–69 D-Index: 172 scientists 70–71 D-Index: 199 scientists 72–73 D-Index: 184 scientists 74–75 D-Index: 133 scientists 76–77 D-Index: 163 scientists 78–79 D-Index: 127 scientists 80–81 D-Index: 121 scientists 82–83 D-Index: 125 scientists 84–85 D-Index: 121 scientists 86–87 D-Index: 102 scientists 88–89 D-Index: 96 scientists 90–91 D-Index: 75 scientists 92–93 D-Index: 72 scientists 94–95 D-Index: 74 scientists 96–97 D-Index: 66 scientists 98–99 D-Index: 68 scientists 100–101 D-Index: 49 scientists 102–103 D-Index: 60 scientists 104–105 D-Index: 54 scientists 106–107 D-Index: 36 scientists 108–109 D-Index: 23 scientists 110–111 D-Index: 52 scientists 112–113 D-Index: 41 scientists 114–115 D-Index: 34 scientists 116–117 D-Index: 25 scientists 118–119 D-Index: 28 scientists 120–121 D-Index: 11 scientists 122–123 D-Index: 20 scientists 124–125 D-Index: 27 scientists 126–127 D-Index: 19 scientists 128–129 D-Index: 20 scientists 130–131 D-Index: 16 scientists 132–133 D-Index: 17 scientists 134–135 D-Index: 14 scientists 136–137 D-Index: 15 scientists 138–139 D-Index: 9 scientists 140–141 D-Index: 11 scientists 142–143 D-Index: 9 scientists 144–145 D-Index: 9 scientists 146–147 D-Index: 7 scientists 148–149 D-Index: 7 scientists 150–151 D-Index: 7 scientists 152–153 D-Index: 5 scientists 154–155 D-Index: 8 scientists 156 D-Index: 6 scientists 157+ D-Index: 96 scientists
40–41 D-Index 157+

This scientist: 56 D-Index — 26th percentile

26% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 157 D-Index or more.

View D-Index distribution as a table
Number of Immunology scientists by D-index, Research.com 2026 ranking edition. Based on 4,929 ranked scientists.
D-Index Scientists This scientist
40–41 28
42–43 91
44–45 157
46–47 192
48–49 175
50–51 188
52–53 177
54–55 155
56–57 194 56
58–59 201
60–61 197
62–63 201
64–65 173
66–67 167
68–69 172
70–71 199
72–73 184
74–75 133
76–77 163
78–79 127
80–81 121
82–83 125
84–85 121
86–87 102
88–89 96
90–91 75
92–93 72
94–95 74
96–97 66
98–99 68
100–101 49
102–103 60
104–105 54
106–107 36
108–109 23
110–111 52
112–113 41
114–115 34
116–117 25
118–119 28
120–121 11
122–123 20
124–125 27
126–127 19
128–129 20
130–131 16
132–133 17
134–135 14
136–137 15
138–139 9
140–141 11
142–143 9
144–145 9
146–147 7
148–149 7
150–151 7
152–153 5
154–155 8
156 6
157+ 96
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Overview

Koichi Hirai is affiliated with the University of Tokyo in Japan and has contributed to multiple areas within medical science. Their research spans a variety of focused disciplines, including surgery, health, toxicology and mutagenesis, emergency medical services, molecular biology, and orthopedics and sports medicine.

The scientist's work covers several interrelated topics, notably water treatment and disinfection, pediatric health and respiratory diseases, polyamine metabolism and applications, hip and femur fractures, bone health and osteoporosis research, and pelvic and acetabular injuries.

Koichi Hirai has authored papers published in reputable venues such as:

  • Organic Process Research & Development
  • Journal of Orthopaedic Science

Recent publications include:

  • "Exploration for Chemical Filter Cartridges that Can Reduce Nitrogen Oxides, a Common Factor in the Formation of Nitrosamines," published in 2024 in Organic Process Research & Development
  • "Determinants of length of stay after first admission for osteoporotic proximal femoral fracture in Japan," published in 2025 in the Journal of Orthopaedic Science

The frequent coauthors collaborating with Koichi Hirai reflect a multidisciplinary approach, encompassing contributions from researchers such as R. Nomura, Takahiko Taniguchi, Kazuya Suzuoki, Rintaro Yokoi, and Kenji Akasaki.

Best Publications

  • Expression and Function of Toll-Like Receptors in Eosinophils: Activation by Toll-Like Receptor 7 Ligand

    Hiroyuki Nagase;Shu Okugawa;Yasuo Ota;Masao Yamaguchi

  • Inducible Expression of a Th2-Type CC Chemokine Thymus- and Activation-Regulated Chemokine by Human Bronchial Epithelial Cells

    Takashi Sekiya;Misato Miyamasu;Masako Imanishi;Hirokazu Yamada

  • Th1- and Th2-Type Cytokines Regulate the Expression and Production of Eotaxin and RANTES by Human Lung Fibroblasts

    Luis M. Teran;Mitsuru Mochizuki;Joachim Bartels;Elba L. Valencia

  • Molecular Cloning of a Novel Human CC Chemokine (Eotaxin-3) That Is a Functional Ligand of CC Chemokine Receptor 3 *

    Motoji Kitaura;Noriko Suzuki;Toshio Imai;Shin Takagi

  • Interleukin-12 p40 gene (IL12B) 3'-untranslated region polymorphism is associated with susceptibility to atopic dermatitis and psoriasis vulgaris.

    Yuichiro Tsunemi;Hidehisa Saeki;Koichiro Nakamura;Takashi Sekiya

  • Idiopathic pulmonary fibrosis and high prevalence of serum antibodies to hepatitis C virus.

    Takashi Ueda;Ken Ohta;Naohito Suzuki;Masao Yamaguchi

  • Modulation of human basophil histamine release by hemopoietic growth factors.

    K Hirai;Y Morita;Y Misaki;K Ohta

  • Expression of CXCR4 in Eosinophils: Functional Analyses and Cytokine-Mediated Regulation

    Hiroyuki Nagase;Misato Miyamasu;Masao Yamaguchi;Takao Fujisawa

  • Chemokine production by the BEAS-2B human bronchial epithelial cells: Differential regulation of eotaxin, IL-8, and RANTES by TH2- and TH1-derived cytokines

    Takao Fujisawa;Yoshiko Kato;Jun Atsuta;Akihiko Terada

  • Concerted expression of eotaxin-1, eotaxin-2, and eotaxin-3 in human bronchial epithelial cells.

    Akiko Komiya;Hiroyuki Nagase;Hirokazu Yamada;Takashi Sekiya

  • Chemokines induce eosinophil degranulation through CCR-3.

    Takao Fujisawa;Yoshiko Kato;Hiroyuki Nagase;Jun Atsuta

  • Cytokine-mediated regulation of CXCR4 expression in human neutrophils.

    Hiroyuki Nagase;Misato Miyamasu;Masao Yamaguchi;Masako Imanishi

  • Increased levels of a TH2‐type CC chemokine thymus and activation‐regulated chemokine (TARC) in serum and induced sputum of asthmatics

    T. Sekiya;H. Yamada;M. Yamaguchi;K. Yamamoto

  • Attenuation of airway hyperresponsiveness in a murine asthma model by neutralization of granulocyte-macrophage colony-stimulating factor (GM-CSF).

    Naomi Yamashita;Hiroyuki Tashimo;Hirobumi Ishida;Fujito Kaneko

  • Involvement of IRAK-M in peptidoglycan-induced tolerance in macrophages.

    Kuniko Nakayama;Shu Okugawa;Shintaro Yanagimoto;Takatoshi Kitazawa

  • Elevated Levels of Eotaxin and interleukin-5 in Blister Fluid of Bullous Pemphigoid: Correlation With Tissue Eosinophilia

    M. Wakugawa;K. Nakamura;H. Hino;K. Toyama

  • Growth inhibition of human lung cancer cell lines by interleukin 6 in vitro: a possible role in tumor growth via an autocrine mechanism.

    Hajime Takizawa;Takayuki Ohtoshi;Ken Ohta;Naomi Yamashita

  • Presence of eotaxin in tears of patients with atopic keratoconjunctivitis with severe corneal damage.

    Kazumi Fukagawa;Toshiharu Nakajima;Kazuo Tsubota;Shigeto Shimmura

  • Eotaxin is a potent chemotaxin for human basophils.

    Hirokazu Yamada;Koichi Hirai;Misato Miyamasu;Motoyasu Iikura

  • Increased levels of a TH2-type CC chemokine thymus and activation-regulated chemokine (TARC) in serum and induced sputum of asthmatics

    Takashi Sekiya;Hirokazu Yamada;Masao Yamaguchi;Akira Ishii

  • Enhancement of human basophil histamine release by interleukin 5.

    Koichi Hirai;Masao Yamaguchi;Yoshikata Misaki;Toshiaki Takaishi

Frequent Co-Authors

Ken Ohta
Ken Ohta Teikyo University
Kouji Matsushima
Kouji Matsushima Tokyo University of Science
Osamu Yoshie
Osamu Yoshie Kindai University
Tadashi Kasahara
Tadashi Kasahara Jichi Medical University
Kunihiko Tamaki
Kunihiko Tamaki University of Tokyo
Hidehisa Saeki
Hidehisa Saeki Nippon Medical School
Kazunori Nakajima
Kazunori Nakajima Keio University
Hirohisa Saito
Hirohisa Saito Juntendo University
Chisei Ra
Chisei Ra Juntendo University

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Salary considerations are also important when planning your career. Understanding how much does a dnp make across different states can help guide decisions about where to study and work, balancing financial goals with professional growth.

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