Sökning: "Sex ratio"

Visar resultat 6 - 10 av 280 avhandlingar innehållade orden Sex ratio.

1. 6. ENVIRONMENTAL CONTAMINANTS AND SPERM Y:X CHROMOSOME RATIO. Impact of androgen- and dioxin-related effects in vivo and in vitro

   Författare :Tarmo Tiido; Malmö Reproduktionsmedicin; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; AR; polymorphisms; Sertoli cell; endocrine disruption; inhibitory cross-talk; Biomedicinska vetenskaper; Biomedical sciences; AHR; sperm Y:X chromosome ratio; sex ratio; POPs; TCDD;

   Sammanfattning : During the last decades, there has been concern that the environmental contaminants, such as POPs, may contribute to sex ratio changes in offspring of exposed populations. Accidental exposure to TCDD has been shown to be associated with fewer sons in men who were exposed in adolescence or earlier in life. LÄS MER

3. 7. Depression among Swedish 70-year-olds - Sex differences from a gender perspective

   Författare :Therese Rydberg Sterner; Göteborgs universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; depression; time trend; epidemiology; sex; gender; experiences; older adults;

   Sammanfattning : Depression is one of the leading causes of global burden of disease. Due to increased life expectancy, late-life depression is an escalating public health issue. The prevalence is reported to be almost twice as high among women compared to men. LÄS MER

4. 8. The evolution of sex chromosomes and sex-linked sequences in birds

   Författare :Homa Papoli Yazdi; Hans Professor; Bengt Hansson; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; sex chromosomes; female heterogamety; recombination suppression; genetic map; inversions; genetic diversity; pseudoautosomal region; Biology with specialization in Evolutionary Genetics; Biologi med inriktning mot evolutionär genetik;

   Sammanfattning : Identifying the processes involved in the evolution of suppressed recombination between sex chromosomes and understanding their consequences for the evolutionary dynamics of sex-linked loci have been major topics of research during the last century. In this thesis, I used the avian ZW system, where females are the heterogametic sex, to investigate the underlying processes in sex chromosome evolution in birds. LÄS MER

5. 9. Chiral building blocks for synthesis of pine sawfly sex pheromones Enantioselective Lipase Catalysed Acylations and Esterifications of Primary Alcohols and Acids and Synthesis of the Sex Pheromone of the Pine Sawfly Microdiprion pallipes

   Författare :Ba-Vu Nguyen; KTH; []
   Nyckelord :lipase; Pseudomonas cepacia; Candida rugosa; enantioselective; enantiomeric ratio; primary 2-methylalcohol; substituted-methylcarboxylic acid; pine sawfly; Microdiprion pallipes; sex pheromone; 3; 7; 11-trimethyl-2-tridecanol; stereoisomer;

   Sammanfattning : This thesis describes the development of new methods for thepreparation of enantiomerically pure methyl branched alkylcompounds and their use as building blocks in the synthesis ofstereoisomerically pure pheromones of pine sawflies.The high regioselectivity, enantioselectivity and activityof lipases in organic solvent in conjunction withenvironmentally compatible reaction conditions have madelipase-catalysed synthesis an attractive alternative toconventional synthetic methods in organic chemistry. LÄS MER

7. 10. ELOVL2 and PUFA biosynthesis : Impact on sex-specific processes in mammals

   Författare :Amanda González-Bengtsson; Anders Jacobsson; Christian Drevon; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fysiologi; Physiology;

   Sammanfattning : Endogenously synthesized PUFAs (Polyunsaturated Fatty Acids) vary in production depending on medical conditions, gender, developmental phase, age, fertility status, pregnancy and lactation. PUFA biosynthesis is further regulated via amount of dietary intake as well as genetically. LÄS MER