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731.
Bruno Gabriel Nunes Pralon Jenniffer Sharon Pinheiro Victor Enzo Santos Damasceno João Gabriel Farias Cavalcante Douglas Fernandes Rodrigues Alves 《Invertebrate reproduction & development.》2019,63(1):23-29
The aim of this study was to investigate the relative growth and onset of morphological sexual maturity of the freshwater crab Sylviocarcinus pictus. Specimens were collected every month from October 2013 to September 2014, at night, on a stretch of the river Guaribas, Piauí, Brazil. Crabs were sexed and their carapace width (CW, independent variable), carapace length (CL), cheliped propodus length (PL) and height (PH), gonopod length (GL), and abdomen width (AW) (dependent variables) were measured. These measurements were related to characterise relative growth and possible sex differences. On average males were larger than females (p = 0.0001). Size at the onset of morphological sexual maturity was defined by relating CL vs. PL for males (30.82 mm) and CL vs. AW for females (28.63 mm). These are considered secondary sexual characters and reflect initial size at morphological sexual maturity with greater precision. The differential cheliped growth of males may be related to courting and disputes with other males, while the allometric growth of the abdomen of females indicates increased probability of reproductive success. 相似文献
732.
Dr. Enzo Insalaco 《Facies》1999,40(1):81-99
Summary This study documents the facies and fauna of Late Jurassic (Middle Oxfordian) coral reefs in England. Sedimentological and
palaeoecological analysis of these reefs distinguishes three generic reef types: (1) small reef patches and thickets associated
with siliciclastic deposits; (2) small reef patches and thickets associated with siliciclastic-free bioclastic grainstones
and packstones; and (3) biostromal units associated with deep water facies. The depositional environments of these reef types
are discussed. Two coral assemblages are identified: (1) the microsolenid assemblage; and (2) theThamnasteria, Isastraea, Fungiastraea andThecosmilia assemblage (Thamnasteria assemblage). TheThamnasteria assemblage developed in all shallow water environments in the study area, regardless of local environmental conditions. The
fauna is very eurytopic,r-selected and can tolerate significant environmental fluctuations on short temporal scales (sub-seasonal). The main control
on the development of the microsolenid assemblage was low light intensity, low background sedimentation rates and low hydrodynamic
energy levels. 相似文献
733.
The effect of cyproterone acetate (CA) on the pituitary-testicular axis was studied in 6 healthy men. A dose of 300 mg of CA was administered orally in the early morning, after 3 h blood samples were collected using a multiple sample technique. Testosterone (T) levels were decreased by CA in all subjects (p 0.01), LH in all (p less than 0.01) but one whereas 17-hydroxyprogesterone did not show any significant variation. In vitro, using an equilibrium dialysis, CA displaced T from plasma-binding proteins in males at 37 degrees C. The role of testosterone-binding globulin on the effects of CA on the pituitary-testicular axis remains to be clarified. 相似文献
734.