1. Osteoporosis: A big challenge to public health

   • Olli Simonen

   Editorial Pages: 295 - 296

2. Calcitonin secretion in streak gonad syndrome (Turner's syndrome)

   • Janos Zseli
   • Peter Bosze
   • Istvan Hollo

   Clinical Investigations Pages: 297 - 299

3. Absence of evidence for a role of calcitonin in the etiology of femoral neck fracture

   • T. R. O. Beringer
   • J. Ardill
   • H. McA Taggart

   Clinical Investigations Pages: 300 - 303

4. Effects of the intravenous administration of magnesium sulfate on corrected serum calcium level and nephrogenous cyclic AMP excretion in normal human subjects

   • Koyasu Suzuki
   • Kyohei Nonaka
   • Seiichiro Tarui

   Clinical Investigations Pages: 304 - 309

5. Radioimmunoassay for human osteocalcin using an antibody raised against the synthetic human (h37–49) sequence

   • Harald Jüppner
   • Thomas Schettler
   • Rolf-Dieter Hesch

   Clinical Investigations Pages: 310 - 315

6. Plasma calcium and phosphate levels in an adult noninsulin-dependent diabetic population

   • J. Levy
   • Z. Stern
   • L. V. Avioli

   Clinical Investigations Pages: 316 - 318

7. Inhibition ofin vitro mineralization by aluminum in a clonal osteoblastlike cell line, MC3T3-E1

   • Kyoji Ikeda
   • Toshio Matsumoto
   • Etsuro Ogata

   Laboratory Investigations Pages: 319 - 323

8. The effects of proteoglycans from different cartilage types onin vitro hydroxyapatite proliferation

   • C. C. Chen
   • A. L. Boskey

   Laboratory Investigations Pages: 324 - 327

9. 25-Hydroxyvitamin D₃ metabolism in a human leukemia cell line

   • Zvi Bar-Shavit
   • Ronald L. Horst
   • Steven L. Teitelbaum

   Laboratory Investigations Pages: 328 - 333

10. In vitro bone resorption activity produced by a hypercalcemic adenocarcinoma tumor line (CAC-8) in nude mice

    • T. J. Rosol
    • C. C. Capen
    • C. Minkin

    Laboratory Investigations Pages: 334 - 341

11. Pancreatic calculi containing brushite: Ultrastructure and pathogenesis

    • Allen L. Rodgers
    • Myron Spector

    Laboratory Investigations Pages: 342 - 347

12. Magnesium in tooth enamel and synthetic apatites

    • R. A. Terpstra
    • F. C. M. Driessens

    Laboratory Investigations Pages: 348 - 354

13. Announcements

    Announcement Pages: 355 - 355

14. Preliminary studies of the secondary structure in solution of two phosphoproteins of chicken bone matrix by circular sichroism and sourier transform-infrared spectroscopy

    • V. Renugopalakrishnan

    Erratum Pages: 356 - 356