Total resorption

Newt, Notophthalmus viridescens adults, single acute exposure of 20 Gy, one limb shielded or 22 Gy, whole body, no limbs shielded Frog, Rana sp., single acute exposure Forelimb regeneration completely suppressed when limbs to be amputated were irradiated directly. Irradiated limbs had severe and protracted inflammation, with total resorption of the affected limbs in 85% of the cases. Shielded limbs subsequently amputated had delays — but not suppression — in rate of forelimb regeneration and skin graft rejection 4... 

In animals, oral exposure to carbon tetrachloride at doses of 1,400 mg/kg/day during gestation caused marked maternal toxicity in rats, and there was total resorption of fetuses in some animals, but no teratogenic effects or other adverse effects were apparent in surviving litters (Wilson 1954). 

Developmental Toxicity. Limited data suggest that carbon tetrachloride has a low potential for developmental toxicity in animals. Fetal size was reduced and viability and lactation indices were decreased following high-level inhalation exposure (Gilman 1971 Schwetz et al. 1974). Fetotoxicity and teratogenicity were not seen in offspring coming to term, but total resorption of fetuses occurred... 

Some litters may have 100% postimplantation loss, known as total litter loss or total resorption. This may represent an extreme case of increased postimplantation loss, particularly when many litters show such an increase however, it may also represent a separate, and sometimes incidental, phenomenon. For some substances, the effect is an all-or-none effect. 

Resorption of bone tissue occurs in total hip joint replacement patients if sufficient stresses are not adequately transmitted to the remaining bone in exactiy the same way that the bone transmitted those stresses originally. Therefore, the design and proper placement of the neck coUar and hip stem must be effective in recreating anatomical stmcture. 

CalcitrioPs action primary function is in regulating plasma calcium concentration. In health, the plasma total calcium concentration is tightly controlled at 2.35-2.55 mmol/1. Only the ionized or free fraction, amounting to about 50% of the total, is physiologically active in for example, maintenance of membrane electrical potential and bone formation. The hormone causes increased bone resorption via activation of osteoclasts (see Section 9.4) and increased intestinal absorption of calcium following the synthesis of a specific binding protein in mucosal cells. As described in Section 4.7, some... 

Drugs acting only on the distal tubule (however complete the resulting block of sodium resorption at that site) are limited, in the effect obtainable, by the comparatively small contribution to total sodium reclamation made by this portion of the nephron. For example, even at their activity peak, thiazide diuretics cause the elimination of only 8 per cent of the total filtered sodium [302, 303] Very much higher proportions of filtered sodium would be expected to contribute to diuresis if the mechanisms of the loops of Henle could be blocked (this has, in fact, proved to be the case in that frusemide and ethacrynic acid are both capable of clearing up to 20 per cent of filtered sodium [302, 304-6]). 

In animals, the frequency of abnormal sperm morphology did not increase significantly over controls in mice exposed to concentrations of 10 ppm hexachlorobutadiene (NIOSH 1981). When mice were exposed to 50 ppm (the only other concentration tested), all animals died during the 5 week post-treatment period. Thus, a reliable NOAEL value for reproductive effects cannot be identified for this study. When rat dams were exposed to vapors of hexachlorobutadiene (up to 15 ppm) during gestation (gestation days 6-20), the mean number of implantation sites, total fetal loss, resorptions and number of live fetuses were comparable to unexposed controls (Saillenfait et al. 1989). 

Post-implantation loss is the total of early resorptions, late resorptions, and dead femses. To distinguish early from late resorptions, the following is a good guidance in late resorptions, the embryonic remainders can be distinguished from placental ones, while this differentiation is impossible in early ones. 

Groups of 26-30 female NMRI mice were fed diets containing 0, 0.05, 0.1 and 0.25% coumarin on days 6-17 of gestation. There was no effect on the total number of implantations or on the proportions that were resorptions or fetal deaths, nor any reduction in fetal weight (Roll Bar, 1967). 

Figure 25 Generalized scheme of protein and lipid changes during the development of embryos and larvae (endogenous feeding). Protein in 1, whole egg 2, egg capsule 3, yolk and 4, embryo. 5, Total lipids in embryo. I, hatching from egg n, transfer to mixed feeding HI, total yolk resorption Max, maximum body mass.

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