The function of digestive physiology during ontogenetic development is essential to ensure high survival and growth rates. In order to evaluate the digestive physiological capacity of the black Amur bream (Megalobrama terminalis), changes of morphology and digestive enzyme activity (trypsin, lipase, amylase, pepsin, leucine aminopeptidase and alkaline phosphatase) in larvae were examined from hatching to 40 days after hatching (DAH). Results indicated that fluctuation patterns differed between the total and specific activities of the digestive enzymes. The total activities of these six enzymes gradually increased throughout the fish growth. The specific activity of trypsin peaked at 5 DAH and then decreased dramatically, while it increased remarkably again from 8 to 10 DAH and remained stable level after 20 DAH. Pepsin activity was first examined in M. terminalis at 15 DAH and gradually elevated towards the end of the experiment. The specific activity of lipase displayed obvious peaks at 5 and 20 DAH. For the amylase, its specific activity reached plateau at 4 DAH, underwent sharp decrease, and remained stable after 20 DAH. In addition, we found that the specific activity of alkaline phosphatase raised significantly from hatching to 5 DAH, and tended to keep slight fluctuation after 15 DAH. From the above, we concluded that the specific activities of digestive enzymes in the larvae varied constantly from 3 to 20 DAH and turned relatively stable after 20 DAH. The present study provides effective information that is useful to improve the seedling cultivation and the technology for healthy breeding. 相似文献
Soybean(Glycine max[L.]Merr.)is a food and oil crop whose growth and yield are influenced by root and nodule development.In the present study,Gm NMHC5 was found to promote the formation of nodules in overexpressing mutants.In contrast,the number of nodules in Gmnmhc5 edited with CRISPR/Cas9 decreased sharply.In 35 S:Gm NMHC5 mutants,expression levels of genes involved in nodulation were significantly up-regulated.Both in vitro and in vivo biochemical analyses showed that Gm NMHC5 directly interacted with Gm GAI(a DELLA protein),and the content of gibberellin 3(GA3)in overexpressing mutants was lower than that in the wild type.These results revealed that Gm NMHC5 participates in the classical GA signaling pathway,and may regulate the content of GA_3 to match the optimal concentration required for nodule formation,thereby promoting nodulation by directly interacting with Gm GAI.A model illustrating the mechanism by which Gm NMHC5 promotes soybean nodulation is presented. 相似文献
Constitutive Hedgehog (Hh) pathway activity is associated with initiation of neoplasia, but its role in the continued growth of established tumors is unclear. Here, we investigate the therapeutic efficacy of the Hh pathway antagonist cyclopamine in preclinical models of medulloblastoma, the most common malignant brain tumor in children. Cyclopamine treatment of murine medulloblastoma cells blocked proliferation in vitro and induced changes in gene expression consistent with initiation of neuronal differentiation and loss of neuronal stem cell-like character. This compound also caused regression of murine tumor allografts in vivo and induced rapid death of cells from freshly resected human medulloblastomas, but not from other brain tumors, thus establishing a specific role for Hh pathway activity in medulloblastoma growth. 相似文献
Under rapid climate change, soil organic carbon (SOC) dynamic in frozen ground may significantly influence terrestrial carbon cycles. The aim of this study was to investigate the storage, spatial patterns, and influencing factors of SOC in frozen ground on the Qinghai-Tibet Plateau, which known as the earth’s Third Pole.
Materials and methods
Using the observed edaphic data from China’s Second National Soil Survey, we estimated the SOC storage (SOCS) of frozen ground (including permafrost, seasonally, and short time frozen ground) on the plateau with a depth of 0–3 m. Furthermore, the effect of vegetation and climate factors on spatial variance of SOC density (SOCD) was analyzed.
Results and discussion
The SOCD decreased from the southeastern to the northwestern part of the plateau, and increased with shorten of freezing duration. SOCS of permafrost, seasonally, and short time frozen ground were calculated as 40.9 (34.2–47.6), 26.7 (24.1–29.4), and 6 (5.6–6.4) Pg, making a total of 73.6 (63.9–83.3) Pg in 0–3 m depth on the plateau. Normalized difference vegetation index and mean annual precipitation could significantly affect the spatial distribution of SOC in permafrost and seasonally frozen ground.
Conclusions
The soil in plateau frozen ground contained substantial organic carbon, which could be affected by plant and climate variables. However, the heterogeneous landform may make the fate of carbon more complicated in the future.
The purposes of this study were to assess the improvement of fatty liver induced by ethanol with animal liver and bile extracts. This research aimed to increase the economic values of animal liver and bile extracts and used these to reduce damage of ethanol‐induced fatty liver. Extracts came from animal liver and bile, including pig bile powder, pig liver extract, a mixture of pig bile powder and pig liver extract, chicken bile powder, chicken liver extract, and a mixture of chicken bile powder and chicken liver extract, and these were fed to Long‐Evans rats. The results showed that rats fed ethanol for long terms could increase values of aspartate transaminase, cholesterol, γ‐glutamy‐transferase and alkaline phosphatase. Pig bile powder could decrease the values of aspartate transaminase, cholesterol and γ‐glutamy‐transferase. The significances also decreased on aspartate transaminase, γ‐glutamy‐transferase and aspartate transaminase, which were carried out with the pig liver extract treatment. These results suggest pig bile and liver extracts have high potential to improve rats' ethanol‐induced fatty liver with serum biochemical parameters. 相似文献
Four types of globins for oxygen transport are known in vertebrates, and the haemoglobin is responsible for carrying oxygen in blood. In this study, we found that haemoglobin was also expressed in canine mammary glands. Samples were taken from 26 malignant mammary tumors, 16 normal mammary glands and 10 other normal tissues. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotting and mass spectrometry were used to investigate haemoglobin in mammary tissues. The results indicated that normal canine mammary glands expressed high levels of haemoglobin protein as shown by Coomassie blue staining. The identity of haemoglobin was confirmed by immunoblotting and mass spectrometry, and the mass spectrometry data revealed that both alpha-haemoglobin and beta-haemoglobin were expressed. Relative to normal mammary glands, the levels of haemoglobin expression in mammary tumors were lower. Our results also indicated that the haemoglobin was endogenously produced in mammary gland tissues and was not derived from the erythroid cells. 相似文献