• 식물조직배양학회지
• /
• 제27권4호
• /
• pp.299-307
• /
• 2000

A large amount of information is currently available for somatic embryogenesis of plants. However, one common problem related to somatic embryos is that the conversion rate can be low for some species. Apical meristems are responsible for post-embryonic growth of the embryo. The low percentage observed is most likely a result of poor apical meristem development or defects in the meristem organization during somatic embryogenesis. In flowering plants, apical meristems are well developed by the late heart stage of zygotic embryo development. In conifers, such as white spruce, apical meristems are formed at the pre-cotyledon stage. Thus, apical meristem development occurs very early, prior to the maturation stage of embryo development. Once formed, meristems are stably determined. In the somatic embryo, as exemplified by white spruce, since embryo development is not synchronous, tissue differentiation including apical meristem formation occurs throughout the“maturation”stage. Different apical meristem organizations can be found among different individuals within a population. In contrast to their zygotic counterparts, the apical meristems appear not to be stably determined as their organization, as the shoot apical meristem especially, can be easily modified or disrupted. Precocious germination seldom results in functional plantlets. All these observations suggest that the conditions for somatic embryo maturation have not been optimized or are not suitable for meristem formation and development. The following strategies could improve meristem development and hence conversion: 1. Simulate in ouuio conditions to promote meristem development prior to the“maturation”treatment.2. Prevent deterioration of apical meristem organization during somatic embryo maturation.3. Promote further meristem development during embryo germination.

• 가정과삶의질연구
• /
• 제28권2호
• /
• pp.193-202
• /
• 2010

The purpose of this study is to investigate the prevalence of children's somatic symptoms and the relationships among parent and child variables such as parenting attitude, children's anxiety, emotional expressiveness and somatic symptoms. The subjects were 523 6th grade students in four elementary schools located in Seoul, Busan and Daejeon. All subjects were tested with the Korean version of Children's Somatization Inventory (K-CSI), Parental Rearing Attitude Inventory, State-Trait Anxiety for Children (STAIC), and The Emotional Expressiveness Questionnaire. The collected data were analyzed by the frequency and percentage of somatic symptoms the children had experienced during the last 2 weeks; Pearson's correlation and multiple regression were used for the selected data of 10 somatic symptoms which were experienced by over 10% of the children. The results are summarized as follows: First, abdominal pain, headache, dizziness, and memory failure, in that order, were experienced in over 20% of the children. Second, children's somatic symptoms had significant relations with mothers' and fathers' loving-denial attitudes and their anxiety and emotional expressiveness. Third, children's somatic symptoms were influenced by their anxiety and emotional expressiveness, but not by parenting attitude.

• Journal of Ginseng Research
• /
• 제36권4호
• /
• pp.442-448
• /
• 2012

Somatic embryogenesis is one of good examples of the basic research for plant embryo development as well as an important technique for plant biotechnology such as medicinally important plants. Single embryos develop into normal plantlets with shoots and roots. Therefore, direct single embryogenesis derived from single cells is highly important for normal plant regeneration. Here we demonstrate that the cyclic secondary somatic embryogenesis in Panax ginseng Meyer is a permanent source of embryogenic material that can be used for genetic manipulations. Secondary somatic embryos were originated directly from the primary somatic embryos on hormone-free Murashige and Skoog medium, and proliferated further in a cyclic manner. EM medium (one third of modified MS medium [MS medium containing half amount of NH4NO3 and KNO3] with 2% to 3% sucrose) favored further development of proliferated secondary somatic embryos into plantlets with root system. The plantlets developed into plants with well-developed taproots in half-strength Schenk and Hildebrandt basal medium supplemented with 0.5% activated charcoal.

• Journal of Plant Biology
• /
• 제39권2호
• /
• pp.127-135
• /
• 1996

An efficient system of somatic embryogenesis was established for the red pepper plant (Capsicum annuum L. cv. Nokkwang) usign immature zygotic embryos. The size of the immature zygotic embryos and the concentrations of 2, 4-D and sucrose were found to be critical. Somatic embryos were induced via callus or directly from explants and regenerated into plantlets successfully. When zygotic embryos 1~2 mm long were cultured on the modified Murashige-Skoong (MS) medium supplemented with 2 mg/L 2, 4-D for 3 weeks in the dark, somatic embryos were induced directly from the apical region of zygotic embryos with the highest frequency being approximately 90%. To mature the somatic embryos, ABA and an ethylene inhibitor AgNO3 were used. The highest frequency of shoot regeneration (25% in each) resulted at 2$\mu$M ABA or 20$\mu$M AgNO3 treatment at rates 3.7 and 1.6 times control, respectively. Shoots developed mainly from the cotyledonary node on CoCl2-containing medium, and from the upper side of cotyledon on medium containing AgNO3 while the embryos on the control medium produced shoots from both the cotyledonary node and the upper region of cotyledons both at frequencies of 50%. Indirect somatic embryogenesis via callus was induced at an efficiency of approximately 10% with zygotic embryos 3~4 mm long cultured on MS medium containing 5~10 mg/L, 2, 4-D for 5~7 weeks under a continuous light condition. The plants regenerated from the somatic embryos were morphologically normal. Using scanning electron microscopy, the direct and indirect somatic embryogeneses were observed to follow the globular, heart and torpedo stages, similar to zygotic embryogenesis. Also, suspensors appeared in the early globular and ovoid-shaped late globular embryos during indirect somatic embryogenesis.

• 식물조직배양학회지
• /
• 제22권3호
• /
• pp.157-164
• /
• 1995

온전한 접합자배 또는 자엽절편을 오옥신(2,4-D, IAA)과 사이토카이닌(BA, kinetin)이 첨가된 배지에 배양하였다. 접합자배를 온전한 상태로 배양했을 경우, 오옥신은 발아를 억제하였으나 사이토카이닌은 억제하지 않았고, 체세포배의 발생은 발아되지 못하는 배에서만 유도되었다. 자엽절편을 배양한 경우, 기본배지에서 체세포배발생률이 가장 높았다. 오옥신을 첨가한 배지에서는 체세포배가 자엽의 표면에서 산재하여 발생되었는데 비해서 기본배지에서는 자엽의 기부에서만 발생되었다. 2,4-D를 첨가한 배지에서는 체세포배가 자엽의 표피 및 하표피를 포함한 다수의 세포로부터 기원되어 다배로 발생되었다. 이 체세포배를 같은 배지에 배양했을 때 일차배의 표면으로부터 이차배가 발생되었는데 이들의 경우는 주로 표피 또는 하표피의 단세포로부터 유래되었음을 조직학적으로 밝혔다.

• 한국산림과학회지
• /
• 제102권4호
• /
• pp.537-542
• /
• 2013

본 연구는 백합나무 5년생의 실생묘와 체세포묘 간 생리적 요인, 기공 특성 및 DNA 함량 비교를 위해 수행되었다. 광합성율 비교의 경우 실생묘는 $10.67{\mu}mol$ $CO_2m^{-2}s^{-1}$, 체세포묘는 $9.04{\mu}mol$ $CO_2m^{-2}s^{-1}$, 기공전도율의 경우 실생묘가 0.2 mol $H_2Om^{-2}s^{-1}$, 체세포묘가 0.166 mol $H_2Om^{-2}s^{-1}$, 또한 증발산율 비교에서는 실생묘가 1.71 mmol $H_2Om^{-2}s^{-1}$, 체세포묘는 1.513 mmol $H_2Om^{-2}s^{-1}$로 각각 나타나 별 차이가 없었다. 기공밀도(실생묘, 23.33개/$mm^2$; 체세포묘, 22.43개/$mm^2$), 기공길이(실생묘, $25.83{\mu}m$; 체세포묘, $23.46{\mu}m$) 및 기공 폭(실생묘, $15.87{\mu}m$; 체세포묘, $15.3{\mu}m$)비교에서는 모든 실생묘가 체세포묘 보다 수치가 다소 높게 나타났다. Flow cytometry를 이용한 엽조직의 DNA함량 비교에서도 실생묘와 체세포묘간에는 차이가 없었다.

• 한국가축번식학회지
• /
• 제23권4호
• /
• pp.393-398
• /
• 1999

Somatic cell nuclear transfer is an efficient technique for the multiplication of elite livestock, engineering of transgenic animals, cell therapy and xenotransplantation, and analyzing the interactions between nucleus and cytoplasm, for various agricultural, biomedical and research purposes. Since the first somatic cell clone lamb was born, tremendous progress has been made toward developing technology for animal cloning. Viable farm animals and mice have now been produced by nuclear transfer using various fetal and adult somatic cells as nuclei donors. Transgenic clones were also produced from nuclear transfer of transfected somatic cells. In the future, somatic cell nuclear transfer will provide more numerous opportunities, both in basic and appled research as well as immediate uses in the generations of superior clone and transgenic animals. However, further technology refinement and improved understanding of the process are essential for commercial and basic research applications.

• 한국환경성돌연변이발암원학회지
• /
• 제7권2호
• /
• pp.103-111
• /
• 1987

The effects of LET (linear energy transfer) of radiation on the induction of somatic chromosome mutations or gene mutations of Drosophila melanogaster were studied. For detecting somatic chromosome mutations and gene mutations, Drosophila wing spot system and eye-color spot system were used, respectively. The frequencies of somatic chromosome mutations or gene mutations induced after third instar larval treatment with 23 MeV neutrons, thermal neutrons, X-rays were examined. From these data, the RBE(relative biological effectiveness) values of 23 MeV neutrons relative to X-rays for induction of somatic chromosome mutations or gene mutations were calculated. The present results suggest that high LET radiations are efficient than X-ray in producing not only somatic chromosome mutations but also gene mutations.

• 한국임상수의학회지
• /
• 제24권2호
• /
• pp.172-176
• /
• 2007

The objective of this study was to determine the relationship between udder and teat characteristics and somatic cell count (SCC). A total of 749 (73.1%) milk samples from 1,024 quarters of 259 Holstein cows contained less than 200,000 somatic cells/ml, while 132 (12.9%) quarters contained more than 500,000 somatic cells/ml. Prior to data analysis, somatic cell counts were transformed to natural logarithm. The mean SCS {$log_e(SCS/10^3)$} of milk samples from the front quarters was lower than milk samples from the rear quarters. The highest SCS was observed from cows with the step-shaped udder and the pear-shaped teats, respectively. Increased SCS was observed from cows with large teat diameter, short teat length, short distance between the teat tip to floor (p<0.05) and with increase in parity, respectively.

• 동의신경정신과학회지
• /
• 제32권1호
• /
• pp.67-79
• /
• 2021

Objectives: The purpose of this study was to report the effect of Korean medicine treatment on a patient with somatic symptom disorder hospitalized after a traffic accident. Methods: The subject for this study was a patient diagnosed with somatic symptom disorder that worsened after a traffic accident. During hospitalization, herbal medicine, acupuncture, psychotherapy, and other treatments were performed. Clinical effect was evaluated using Heart Rate Variability (HRV), BDI (Beck Depression Inventory)-II, BAI (Beck Anxiety Inventory), Global assessment (G/A), and Numerical rating scale (NRS). Results: After 36 days of treatment, BDI-II score was reduced from 17 to 5. BAI score was reduced from 23 to 8. Overall somatic symptoms and pain showed decreases. Conclusions: Korean medicine treatment might be effective for somatic symptom disorder that is worsened after a traffic accident.