1. Calcium and aging

   • Takuo Fujita

   Editorial Pages: 1 - 2

2. Thirty-one years of bones and teeth—Retrospect and prospect

   • Felix Bronner

   Editorial Pages: 3 - 5

3. Placebo therapy for postmenopausal osteoporosis

   • Christopher Elias
   • Robert P. Heaney
   • Robert R. Recker

   Clinical Investigations Pages: 6 - 13

4. Vertebral bone mineral content in osteogenesis imperfecta

   • David Kurtz
   • Kathleen Morrish
   • Jay Shapiro

   Clinical Investigations Pages: 14 - 18

5. Skeletal challenge: An experimental study of pharmacologically induced changes in bone density in the distal radius, using gamma-ray computed tomography

   • T. N. Hangartner
   • T. R. Overton
   • P. M. Crockford

   Clinical Investigations Pages: 19 - 24

6. Phagocytosis of bone collagen by osteoclasts in two cases of pycnodysostosis

   • Vincent Everts
   • Daniel C. Aronson
   • Wouter Beertsen

   Clinical Investigations Pages: 25 - 31

7. Relationship between toluidine blue-stained calcification fronts and tetracycline-labeled surfaces in normal human iliac crest biopsies

   • J. E. Compston
   • S. Vedi
   • A. Webb

   Clinical Investigations Pages: 32 - 35

8. Ultrastructural distribution of acidic glycosaminoglycans associated with matrix vesicle-mediated calcification in mouse progenitor predentine

   • Yasutoku Kogaya
   • Kuhei Furuhashi

   Laboratory Investigations Pages: 36 - 41

9. Whole-body irradiation inhibits the escape phenomenon of osteoclasts in bones of calcitonin-treated rats

   • Takashi Nakamura
   • Fukai Toyofuku
   • Shigenobu Kanda

   Laboratory Investigations Pages: 42 - 45

10. On the origin of the osteoclast: The cell surface phenotype of rodent osteoclasts

    • M. A. Horton
    • E. F. Rimmer
    • T. J. Chambers

    Laboratory Investigations Pages: 46 - 50

11. Characterization of an osteoblast-like clonal cell line which responds to both parathyroid hormone and calcitonin

    • S. M. Forrest
    • K. W. Ng
    • T. J. Martin

    Laboratory Investigations Pages: 51 - 56

12. The effect of osteocalcin onIn vitro lipid-induced hydroxyapatite formation and seeded hydroxyapatite growth

    • A. L. Boskey
    • F. H. Wians Jr.
    • P. V. Hauschka

    Laboratory Investigations Pages: 57 - 62

13. Bone-derived macrophage chemotactic factors: Methods of extraction and further characterization

    • C. Minkin
    • D. J. Bannon Jr.
    • S. Pokress

    Laboratory Investigations Pages: 63 - 72

14. The mechanical properties of immature osteopetrotic bone

    • R. B. Ashman
    • W. C. Van Buskirk
    • J. C. Rice

    Laboratory Investigations Pages: 73 - 76

15. Acute metabolic acidosis stimulates³H-25 hydroxyvitamin D production by the rachitic rat liver

    • Moira L. Milne
    • Daniel T. Baran

    Laboratory Investigations Pages: 77 - 81

16. 1α,25-Dihydroxyvitamin D₃ receptors and their action in embryonic chick chondrocytes

    • Satoshi Suda
    • Naoyuki Takahashi
    • Tatsuo Suda

    Laboratory Investigations Pages: 82 - 90

17. Octacalcium phosphate formationin vitro: Implications for bone formation

    • Pei-Tak Cheng

    Laboratory Investigations Pages: 91 - 94

18. Pig interleukin 1 (Catabolin) is a potent stimulator of bone resorptionin vitro

    • Joan K. Health
    • Jeremy Saklatvala
    • John J. Reynolds

    Rapid Communications Pages: 95 - 97

19. Crystallo-chemical properties of apatite in atremate brachiopod shells

    • Racquel Z. LeGeros
    • Chi-Miau Pan
    • Norimitsu Watabe

    Rapid Communications Pages: 98 - 100

20. Intestinal lactase activity and calcium absorption in the aging female with osteoporosis

    • R. Pacifici
    • D. Droke
    • L. V. Avioli

    Comment Pages: 101 - 102

21. Announcements

    Announcement Pages: 103 - 103