1. Bone turnover in male puberty: A longitudinal study

   • Bente J. Riis
   • Søren Krabbe
   • Leonard J. Deftos

   Clinical Investigations Pages: 213 - 217

2. Different actions of vitamin D₂ and D₃ on bone metabolism in patients treated with phenobarbitone/phenytoin

   • Lone Tjellesen
   • Anders Gotfredsen
   • Claus Christiansen

   Clinical Investigations Pages: 218 - 222

3. Serum 1,25-dihydroxyvitamin D concentrations in premature infants: Preliminary results

   • Laura S. Hillman
   • Sharon Salmons
   • Shigeharu Dokoh

   Clinical Investigations Pages: 223 - 227

4. Characterization of human bone cells in culture

   • Bettina Auf'mkolk
   • Peter V. Hauschka
   • Edith R. Schwartz

   Clinical Investigations Pages: 228 - 235

5. In vivo decomposition of phosphoserine and serine in noncollagenous protein from human dentin

   • Patricia M. Masters

   Clinical Investigations Pages: 236 - 241

6. The biosynthesis of dentin phosphophoryns by rat incisor odontoblasts in organ culture

   • Michael T. DiMuzio
   • Meera Bhown
   • William T. Butler

   Laboratory Investigations Pages: 242 - 249

7. Induction of bone by xenografts of rabbit growth plate chondrocytes in the nude mouse

   • George C. Wright Jr.
   • Frederick Miller
   • Leon Sokoloff

   Laboratory Investigations Pages: 250 - 256

8. Demonstration and characterization of 1,25-dihydroxyvitamin D₃ receptors in basal cells of epidermis of neonatal and adult mice

   • Jürgen Merke
   • Dietger Schwittay
   • Eberhard Ritz

   Laboratory Investigations Pages: 257 - 267

9. Inhibition by aminohydroxypropylidene bisphosphonate (AHPrBP) of 1,25(OH)₂ vitamin D₃-induced stimulated bone turnover in the mouse

   • Pierre J. Marie
   • Monique Hott
   • Marie-Thérèse Garba

   Laboratory Investigations Pages: 268 - 275

10. 1,25-dihydroxyvitamin D₃ causes an increase in the number of osteoclastlike cells in cat bone marrow cultures

    • M. J. Pharoah
    • J. N. M. Heersche

    Laboratory Investigations Pages: 276 - 281

11. The effects of continuous progestogen treatment on cortical bone remodeling activity in beagles

    • Gillian R. Snow
    • C. Anderson

    Laboratory Investigations Pages: 282 - 286

12. Mineral and matrix alterations in the bones of incisors-absent (ia/ia) osteopetrotic rats

    • A. L. Boskey
    • S. C. Marks Jr.

    Laboratory Investigations Pages: 287 - 292

13. Morphochemical analysis of phosphorus pools in calcifying cartilage

    • S. Kakuta
    • E. E. Golub
    • I. M. Shapiro

    Laboratory Investigations Pages: 293 - 299

14. Evidence for two pathways for stimulation of collagenolysis in bone

    • Robert L. Jilka
    • James W. Hamilton

    Laboratory Investigations Pages: 300 - 306

15. Calcium homeostasis: The effect of parathyroid hormone on bone membrane electrical potential difference

    • D. R. Peterson
    • W. J. Heideger
    • K. W. Beach

    Laboratory Investigations Pages: 307 - 311

16. The variation with flow-rate of the extraction of bone-seeking tracers in recirculation experiments

    • P. Tothill
    • G. Hooper
    • S. P. F. Hughes

    Laboratory Investigations Pages: 312 - 317

17. Skeletal adenylate cyclase: Effect of Mg²⁺, Ca²⁺, and PTH

    • Robert K. Rude

    Laboratory Investigations Pages: 318 - 323

18. Skeletal alterations in ovariectomized rats

    • T. J. Wronski
    • P. L. Lowry
    • L. A. Ignaszewski

    Laboratory Investigations Pages: 324 - 328

19. The role of octacalcium phosphate in subcutaneous heterotopic calcification

    • M. S. Tung
    • W. E. Brown

    Comment Pages: 329 - 331

20. Letters to the editor

    • C. Anderson

    Letter Pages: 332 - 332

21. Response

    • Sol Epstein

    Letters to the Editor Pages: 332 - 332

22. Announcements

    Announcement Pages: 333 - 333