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Plasma HCS levels have been measured in normal and pathological pregnant women. In the normal group HCS levels increased from 6--8 weeks till 33-34 weeks and then felt significantly. HCS pattern in prediabetic and chemical diabetic pregnant women was similar to the normal group. However HCS levels in chemical diabetics were significantly higher during the first two trimesters. HCS levels increased in twin pregnancy, diminished in cases of eclampsia, hypertension, fetal growth retardation, mole and blighted ovum, and disappeared after intrauterine death. Nothing could be deduced from the obese and Rh-isoimmunization groups. It is confirmed the value of HCS determination as an index of placental maturation. Also, insulin/HCS ratio may be of some aid in the study of carbohydrate intolerance in pregnancy. 相似文献
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Classical theories, such as Bateman's principle and Trivers' parental investment theory, attempted to explain the coevolution of sexual selection and parental care through simple verbal arguments. Since then, quantitative models have demonstrated that it is rarely that simple because many non-intuitive structures and non-linear relationships are actually at play. In this study, we propose a new standard for models of mating dynamics and parental care, emphasizing the clarity and use of mathematical and probabilistic arguments, the meaning of consistency conditions, and the key role of spatial densities and the law of mass action. We used adaptive dynamics to calculate the evolutionary trajectory of the total care duration. Our results clearly show how the outcomes of parental care evolution can be diverse, depending on the quantitative balance between a set of dynamical forces arising from relevant differences and conditions in the male and female populations. The intensity of sexual selection, synergy of care, care quality, and relative mortality rates during mating interactions and caring activities act as forces driving evolutionary transitions between uniparental and biparental care. Sexual selection reduces the care duration of the selected sex, uniparental care evolves in the sex that offers the higher care quality, higher mortality during mating interactions of one sex leads to more care by that sex, and higher mortality during caring activities of one sex favours the evolution of uniparental care in the other sex. Both synergy and higher overall mortality during mating interactions can stabilize biparental care when sexual selection reduces the care duration of the selected sex. We discuss how the interaction between these forces influences the evolution of care patterns, and how sex ratios can vary and be interpreted in these contexts. We also propose new directions for future developments of our integrative model, creating new comparable analyses that share the same underlying assumptions and dynamical frameworks. 相似文献
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B. Blasco J. J. Rios R. Leyva R. Melgarejo C. Constán-Aguilar E. Sánchez-Rodríguez M. M. Rubio-Wilhelmi L. Romero J. M. Ruiz 《Plant Growth Regulation》2011,65(1):137-143
Iodine, essential to human life, is in part ingested through vegetable consumption, explaining the current application of
this element in biofortification programs. Few data are available on the effects of iodine on main plant metabolisms such
as carbon metabolism. The objective of this study was to determine the effect of the application of different doses (20, 40
and 80 μM) and forms of iodine (iodate [IO3
−] and iodide [I−]) on photosynthesis and carbohydrate metabolism in lettuce plants. None of these treatments exerted significant effects on
the synthesis pathway or on sucrose degradation. Application of 80 μM of I− reduced the photosynthesis rate, which may be associated with the reduction found in biomass and photosynthetic parameters
(stomatic conductance and transpiration). This finding confirms that the application of high doses of I− has a phytotoxic effect on plant physiology. In contrast, all IO3
− treatments increased the biomass of the plants which showed an elevated photosynthetic rate, stomatic conductance, and transpiration
(vs. controls). The differential crop behavior observed with the two forms of this trace element suggests that IO3
− should be selected for future biofortification programs. 相似文献
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Amy C. Morrison Julia Schwarz Jennie L. Mckenney Jhonny Cordova Jennifer E. Rios W. Lorena Quiroz S. Alfonso Vizcarra Heng Sopheab Karin M. Bauer Chhorvann Chhea Vonthanak Saphonn Robert D. Hontz Pamina M. Gorbach Valerie A. Paz-Soldan 《PLoS neglected tropical diseases》2021,15(4)
Rapid diagnostic tests (RDTs) have the potential to identify infectious diseases quickly, minimize disease transmission, and could complement and improve surveillance and control of infectious and vector-borne diseases during outbreaks. The U.S. Defense Threat Reduction Agency’s Joint Science and Technology Office (DTRA-JSTO) program set out to develop novel point-of-need RDTs for infectious diseases and deploy them for home use with no training. The aim of this formative study was to address two questions: 1) could community members in Iquitos, Peru and Phnom Penh, Cambodia competently use RDTs of different levels of complexity at home with visually based instructions provided, and 2) if an RDT were provided at no cost, would it be used at home if family members displayed febrile symptoms? Test kits with written and video (Peru only) instructions were provided to community members (Peru [n = 202]; Cambodia [n = 50]) or community health workers (Cambodia [n = 45]), and trained observers evaluated the competency level for each of the several steps required to successfully operate one of two multiplex RDTs on themselves or other consenting participant (i.e., family member). In Iquitos, >80% of residents were able to perform 11/12 steps and 7/15 steps for the two- and five-pathogen test, respectively. Competency in Phnom Penh never reached 80% for any of the 12 or 15 steps for either test; the percentage of participants able to perform a step ranged from 26–76% and 23–72%, for the two- and five-pathogen tests, respectively. Commercially available NS1 dengue rapid tests were distributed, at no cost, to households with confirmed exposure to dengue or Zika virus; of 14 febrile cases reported, six used the provided RDT. Our findings support the need for further implementation research on the appropriate level of instructions or training needed for diverse devices in different settings, as well as how to best integrate RDTs into existing local public health and disease surveillance programs at a large scale. 相似文献
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