AIM: To observe dynamic of different chemical elements in stomach tissue during fetal development.METHODS: To determine contents of the 21 chemical elements in each stomach samples from fetus aging four to ten months....AIM: To observe dynamic of different chemical elements in stomach tissue during fetal development.METHODS: To determine contents of the 21 chemical elements in each stomach samples from fetus aging four to ten months. The content values were compared to those from adult tissue samples, and the values for each month group were also analyzed for dynamic changes.RESULTS: Three representations were found regarding the relationship between contents of the elements and ages of the fetus, including the positive correlative (K), reversely correlative (Na, Ca, P, Al, Cu, Zn, Fe, Mn, Cr, Sr, Li, Cd, Ba,Se ) and irrelevant groups (Mg, Co, Ni, V, Pb, Ti).CONCLUSION: The chemical elements' contents in stomach tissues were found to change dynamically with the stomach weights. The age-dependent representations for different chemical elements during the prenatal development may be of some significance for assessing development of fetal stomach and some chemical elements. The data may be helpful for the nutritional balance of fetus and mothers during prenatal development and even the perinatal stages.展开更多
: The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equ...: The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type I, with foveolate-reticulate sculpture; (ii) type II, with a finely reticulate sculpture; and (iii) type III, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect. Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China, with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassia faberi Oliv.) colpi, implying that Southwest China is the center of diversification of the genus.展开更多
基金the National Natural Science Foundation of China, No.49971003
文摘AIM: To observe dynamic of different chemical elements in stomach tissue during fetal development.METHODS: To determine contents of the 21 chemical elements in each stomach samples from fetus aging four to ten months. The content values were compared to those from adult tissue samples, and the values for each month group were also analyzed for dynamic changes.RESULTS: Three representations were found regarding the relationship between contents of the elements and ages of the fetus, including the positive correlative (K), reversely correlative (Na, Ca, P, Al, Cu, Zn, Fe, Mn, Cr, Sr, Li, Cd, Ba,Se ) and irrelevant groups (Mg, Co, Ni, V, Pb, Ti).CONCLUSION: The chemical elements' contents in stomach tissues were found to change dynamically with the stomach weights. The age-dependent representations for different chemical elements during the prenatal development may be of some significance for assessing development of fetal stomach and some chemical elements. The data may be helpful for the nutritional balance of fetus and mothers during prenatal development and even the perinatal stages.
文摘: The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type I, with foveolate-reticulate sculpture; (ii) type II, with a finely reticulate sculpture; and (iii) type III, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect. Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China, with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassia faberi Oliv.) colpi, implying that Southwest China is the center of diversification of the genus.
