Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Effects of 1,25(OH)2D3 on bone tissue in the rabbit: Studies on fracture healing, disuse osteoporosis, and prednisone osteoporosis (1984)
    Springer
    Calcified tissue international 36 (1984), S. 591-595 
    Details
    ISSN: 1432-0827
    Keywords: Fracture ; (Glucocorticoid ; 1,25(OH)2D3 ; Osteoporosis ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A closed tibial fracture, which was controlled by an intramedullary stainless steel pin, was created in 16 rabbits. Eight rabbits were treated with 75 ng of 1,25(OH)2D3 daily as subcutaneous (s.c.) injections. After three weeks, the fractured tibia resisted a force of 101,7±21.0 Newtons in the control group and 57.3±8.0 Newtons in animals given 1,25(OH)2D3 (m±SE,P〈0.05). In another group of eight rabbits, the left hindleg was immobilized in a plastic splint. Four rabbits were given 75 ng of 1,25(OH)2D3/day s.c. and the effect of immobilization was studied on the calcaneus. Bone ash/cm3 of the calcaneus on the immobilized side was decreased by 11±2% in control rabbits and by 20±2% in the group treated with 1,25(OH)2D3 indicating a more advanced immobilization osteoporosis (m±SE,P〈0.05), which was also demonstrated by studies of bone density. Eighteen rabbits were used in a study of the effects of 1,25(OH)2D3 on the development of prednisolone osteoporosis. The dose of prednisolone was 2.5 mg per day, given by the oral route. After four months, the density of the femur was 1.53±0.02 g/cm2 in control rabbits and 1.42±0.01 in prednisolonetreated animals (P〈0.01). In rabbits additionally given 1,25(OH)2D3, the mean value for bone density was further lowered (n.s.). It appears that 1,25(OH)2D3 exaggerates disuse osteoporosis and prednisolone osteoporosis and impairs fracture healing in rabbits. These results differ from what has been shown earlier with 1,25(OH)2D3 treatment in the rat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02405372
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Metabolism of pentachlorophenol (1974)
    Springer
    Archives of toxicology 32 (1974), S. 271-281 
    Details
    ISSN: 1432-0738
    Keywords: Pentachlorophenol ; Excretion ; Metabolism ; Tetrachlorohydroquinone ; β-glucuronidase ; Pentachlorphenol ; Ausscheidung ; Metabolismus ; Tetrachlorhydrochinon ; β-Glucuronidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Ausscheidung von 14C-Pentachlorphenol im Harn von Ratten und Mäusen wurde nach oraler und intraperitonealer Verabreichung in Dosen von 10 bis 25 mg/kg untersucht. 41 bis 43% der ausgeschiedenen Aktivität waren unverändertes Pentachlorphenol. Mittels kombinierter Gaschromatographie und Massenspektroskopie konnte ein Metabolit, der 5 bzw. 24% der ausgeschiedenen Aktivität bei Ratten bzw. Mäusen ausmacht, als Tetrachlorhydrochinon identifiziert werden. Das Vorhandensein von Glucuronsäure-Konjugaten ließ sich nicht durch enzymatische Hydrolyse nachweisen, da Tetrachlorhydrochinon ein starker β-Glucuronidase-Hemmer (I50 = 1,6 bis 2,0×10−6M) ist. Kochen des Harns mit HCl wandelte die gesamte ausgeschiedene Aktivität in Pentachlorphenol und Tetrachlorhydrochinon um. Davon entfielen 43 (Ratten) bzw. 46% (Mäuse) auf Tetrachlorhydrochinon. Tetrachlorhydrochinon konnte auch im Harn von Arbeitern nachgewiesen werden, die beruflich mit Pentachlorphenol in Kontakt kommen.
    Notes: Abstract Excretion of pentachlorophenol-14C in the urine of rats and mice after oral and intraperitoneal administration (10 to 25 mg/kg) was studied. 41 to 43% of the excretion activity was found to be present as unchanged pentachlorophenol. By means of gas chromatography-mass spectrometry, one metabolite was identified as tetrachlorohydroquinone, representing 5 and 24% of the excreted activity in rats and mice, respectively. Conjugation with glucuronic acid could not be demonstrated by enzymatic hydrolysis since tetrachlorohydroquinone was found to be a potent inhibitor of β-glucuronidase, the I50 being 1.6 to 2.0×10−6 M. Boiling the urine with hydrochloric acid was shown to convert all of the excreted activity to pentachlorophenol and tetrachlorohydroquinone, the latter representing 43 and 46% in rats and mice, respectively. Tetrachlorohydroquinone was found in the urine of workers occupationally exposed to pentachlorophenol.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00330109
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...