Different gestational age fetal follicles of Northeast China Fine-fleece Sheep were histologically studied. The results showed that boundaries between medulla and cortex was ambiguous at the eighth week and became obv...Different gestational age fetal follicles of Northeast China Fine-fleece Sheep were histologically studied. The results showed that boundaries between medulla and cortex was ambiguous at the eighth week and became obvious at the twelfth week. Primordial follicles could be found in 8-week fetal ovaries and some follicle cells became irregular cuboid in 12-week, but primary follicles could be found until 16-week. There was significant difference between 8-week and 12-week follicles in size (P < 0.01), most mitochondria were round, some diamond, irregular and juvenile ones could be found with the development of oocytes. Some of oocytes degenerated in each stage of development. The diameter of primary oocytes, primordial follicles and primordial follicular oocytes were larger in 12-16 weeks fetal ovaries than other times.展开更多
Until recently, fetal surgery was only used for fetuses with very poor prognosis who were likely to die without intervention. With advances in imaging, endoscopic techniques, anesthesia and novel interventions, fetal ...Until recently, fetal surgery was only used for fetuses with very poor prognosis who were likely to die without intervention. With advances in imaging, endoscopic techniques, anesthesia and novel interventions, fetal surgery is becoming a realistic option for conditions with less severe prognoses, where the aim is now to improve quality of life rather than simply allow survival. Until forty years ago, the uterus shielded the fetus from observation and therapy. Rapid changes in the diagnosis and treatment of human fetal anatomical abnormalities are due to improved fetal imaging studies, fetal sampling techniques(e.g., amniocentesis and chorionic villus sampling), and a better understanding of fetal pathophysiology derived from laboratory animals. Fetal therapy is the logical culmination of progress in fetal diagnosis. In other words, the fetus is now a patient. Now-a-days, in utero(IU) and exo utero(EU) surgical methods are popular for experimental analyses of the histogenesis of organ development. Using these surgical methods, developmental anomalies can be created and then repaired. By applying microinjection and/or fetal surgery with these methods, models of developmental anomalies such as neural tube defects, temporomandibular joint defects, hip joint defects, digit amputation, limb and digit development and regeneration, and tooth germ transplantation in the jaw could be created and later observed. After observing different types of anomalies, novel IU and EU surgical techniques would be the best approach for repairing or treating those anomalies or diseases. This review will focus on the rationale for the IU and EU creation of animal models of different organ defects or anomalies and their repair, based on analyses of organ histogenesis and pathologic observations. It will also focus in detail on the surgical techniques of both IU and EU methods.展开更多
文摘Different gestational age fetal follicles of Northeast China Fine-fleece Sheep were histologically studied. The results showed that boundaries between medulla and cortex was ambiguous at the eighth week and became obvious at the twelfth week. Primordial follicles could be found in 8-week fetal ovaries and some follicle cells became irregular cuboid in 12-week, but primary follicles could be found until 16-week. There was significant difference between 8-week and 12-week follicles in size (P < 0.01), most mitochondria were round, some diamond, irregular and juvenile ones could be found with the development of oocytes. Some of oocytes degenerated in each stage of development. The diameter of primary oocytes, primordial follicles and primordial follicular oocytes were larger in 12-16 weeks fetal ovaries than other times.
文摘Until recently, fetal surgery was only used for fetuses with very poor prognosis who were likely to die without intervention. With advances in imaging, endoscopic techniques, anesthesia and novel interventions, fetal surgery is becoming a realistic option for conditions with less severe prognoses, where the aim is now to improve quality of life rather than simply allow survival. Until forty years ago, the uterus shielded the fetus from observation and therapy. Rapid changes in the diagnosis and treatment of human fetal anatomical abnormalities are due to improved fetal imaging studies, fetal sampling techniques(e.g., amniocentesis and chorionic villus sampling), and a better understanding of fetal pathophysiology derived from laboratory animals. Fetal therapy is the logical culmination of progress in fetal diagnosis. In other words, the fetus is now a patient. Now-a-days, in utero(IU) and exo utero(EU) surgical methods are popular for experimental analyses of the histogenesis of organ development. Using these surgical methods, developmental anomalies can be created and then repaired. By applying microinjection and/or fetal surgery with these methods, models of developmental anomalies such as neural tube defects, temporomandibular joint defects, hip joint defects, digit amputation, limb and digit development and regeneration, and tooth germ transplantation in the jaw could be created and later observed. After observing different types of anomalies, novel IU and EU surgical techniques would be the best approach for repairing or treating those anomalies or diseases. This review will focus on the rationale for the IU and EU creation of animal models of different organ defects or anomalies and their repair, based on analyses of organ histogenesis and pathologic observations. It will also focus in detail on the surgical techniques of both IU and EU methods.
