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81.
The localization of mRNA encoding preproatrial natriuretic peptide (ANP) was investigated in cultured human umbilical vein endothelial cells (HUVEC) and tissue preparations of umbilical vein and artery. The techniques used were in situ hybridization and in situ hybridization combined with immunocytochemistry, using 32P-radiolabelled and non-radioactive digoxigenin labelled complementary RNA probes. Human ANP mRNAs are mainly localized in the endothelial cells of the umbilical vein and, to a lesser extent, in the endothelial cells of the umbilical artery. The autoradiographic labelling and the intensity of digoxigenin staining were significantly reduced by treatment with RNase before in situ hybridization. This study provides unequivocal evidence for the expression of the ANP gene in the endothelial cells of human umbilical vessels, confirming that these endothelial cells have the ability to synthesize this peptide. The functional significance of the presence of the ANP mRNA in the endothelial cells of human umbilical vessels is discussed.  相似文献   
82.
Gui  Runfei  Mo  Zhaowen  Zeng  Shan  Wen  Zhiqiang  Long  Weisi 《Journal of Plant Growth Regulation》2023,42(3):1604-1613

Compared with the standard method of manual fertilizer broadcasting (MFB), mechanized hill-drilling direct-seeding with deep application of slow-release nitrogen fertilizer (MHDDF) is an efficient method to integrate both fertilization and seeding. However, there are few studies that combine the use of slow-release fertilizer with MHDDF. We sought to explore the combined effect of MHDDF with slow-release fertilizer on rice yield and nitrogen, phosphorus, and potassium utilization, compared to MFB. We compared three different MHDDF methods (D30: 450 kg ha?1, D40: 600 kg ha?1, D50: 750 kg ha?1), with one MFB method (B50: 750 kg ha?1), and one control (CK: 0 kg ha?1). We found that the yield of all MHDDF method was higher than that of both the MFB method. Yield was the highest in the D50 treatment and was 14.14–46.03% higher than that in B50 treatment. Biomass accumulation, nutrient accumulation, and nutrient use efficiency were similarly higher in MHDDF method than both MFB and CK. Compared to B50, the D50 treatment increased nitrogen recovery efficiency by 170.53–231.50%, phosphorus recovery efficiency by 480.00–724.25%, and potassium recovery efficiency by 201.55–169.59%. Overall, we found that combining MHDDF with slow-release fertilizer was an effective method to increase rice yield and nutrient use efficiency compared with MFB.

  相似文献   
83.
中国南部石灰岩濒危植物的初步研究   总被引:2,自引:2,他引:0  
本文所说中国南部石灰岩地区主要指广西、云南、贵州三省的石灰岩地区,这一地区以其植物的多样性和岩溶特有性而闻名。本文对这一地区的植被和植物保护现状、自然屎护区状况、植物濒危原因筹进行了初步考察和研究。  相似文献   
84.
儿童最大有氧活动能力的发展特征   总被引:4,自引:1,他引:3  
本文报告了我国463名10-19岁儿童青少年的最大有氧活动能力的发展特征。在青春早期,男女童的最大吸氧量绝对值均随年龄增长而增加,男童由1.75升/分增至3.10升/分,女童由1.44升/分增至2.07升/分,女童增长较少;以后女童即稳定于这一水平,男童仍略有增长。按身高及按最大心率计标的相对值与其有相似的特征。按体重和瘦体重计算的相对值,在男女童都未见随年龄增长的规律。男童VO2max绝对值及各  相似文献   
85.
To determine 15 bile acid metabolic products in human serum by liquid chromatography-tandem mass spectrometry (LC/MS/MS) and value their diagnostic outcome in primary biliary cholangitis (PBC). Serum from 20 healthy controls and 26 patients with PBC were collected and went LC/MS/MS analysis of 15 bile acid metabolic products. The test results were analyzed by bile acid metabolomics, and the potential biomarkers were screened and their diagnostic performance was judged by statistical methods such as principal component and partial least squares discriminant analysis and area under curve (AUC). 8 differential metabolites can be screened out: Deoxycholic acid (DCA), Glycine deoxycholic acid (GDCA), Lithocholic acid (LCA), Glycine ursodeoxycholic acid (GUDCA), Taurolithocholic acid (TLCA), Tauroursodeoxycholic acid (TUDCA), Taurodeoxycholic acid (TDCA), Glycine chenodeoxycholic acid (GCDCA). The performance of the biomarkers was evaluated by the AUC, specificity and sensitivity. In conclusion, DCA, GDCA, LCA, GUDCA, TLCA, TUDCA, TDCA and GCDCA were identified as eight potential biomarkers to distinguish between healthy people and PBC patients by multivariate statistical analysis, which provided reliable experimental basis for clinical practice.  相似文献   
86.
87.
This work firstly reported a new polycaprolactone based material functionalized with guanidinium ionic liquid (PCL-GIL) as the stationary phase with high resolution performance for capillary gas chromatography (GC). It is composed of polycaprolactone (PCL) and guanidinium ionic liquid (GIL) with amphiphilic conformation. The PCL-GIL capillary column coated by static method exhibited high column efficiency of 3942 plates/m and moderate polarity. As a result, the PCL-GIL column exhibited high-resolution capability. For a mixture of 27 analytes with a wide ranging polarity and outperformed the PCL-2OH and HP-35 columns, showing its advantageous separation capability for analytes of diverse types. Moreover, the PCL-GIL column showed high resolving capability for various positional isomers and cis-/trans-isomers, including alkylbenzenes, chlorobenzenes, naphthalenes, bromonitrobenzenes, chloronitrobenzenes, benzaldehydes, phenols, alcohols, respectively. In a word, PCL derivatized by GIL units as a new type of stationary phase has a promising future in GC separations.  相似文献   
88.
89.
Diversification rates are critically important for understanding patterns of species richness among clades. However, the effects of climatic niche width on plant diversification rates remain to be elucidated. Based on the phylogenetic, climatic, and distributional information of angiosperms in China, a total of 26 906 species from 182 families were included in this study. We aimed to test relationships between diversification rate and climatic niche width and climatic niche width related variables (including climatic niche divergence, climatic niche position, geographic extent, and climatic niche evolutionary rate) using phylogenetic methods. We found that climatic niche divergence had the largest unique contribution to the diversification rate, while the unique effects of climatic niche width, climatic niche position, geographic extent, and climatic niche evolutionary rate on the diversification rate were negligible. We also observed that the relationship between diversification rate and climatic niche divergence was significantly stronger than the null assumption (artefactual relationship between diversification and clade-level climatic niche width by sampling more species). Our study supports the hypothesis that wider family climatic niche widths explain faster diversification rates through a higher climatic niche divergence rather than through higher geographic extent, higher climatic niche evolutionary rate, or separated climatic niche position. Hence, the results provide a potential explanation for large-scale diversity patterns within families of plants.  相似文献   
90.
Professor Wen-Tsai Wang (王文采, June 5, 1926–November 16, 2022) was an academician of the Chinese Academy of Sciences (CAS) and a legendary plant taxonomist at the Institute of Botany of CAS (Fig.1). Herein, we organize a virtual special issue in Journal of Systematics and Evolution (JSE) to celebrate the legacy and life of Professor Wang, who was a leading plant taxonomist in China and made important contributions toward advancing the understanding of the flora of China, the biogeography of eastern Asia, and biodiversity research in the vast Hengduan Mountains. He served as the Editor-in-Chief of Acta Phytotaxonomica Sinica (now JSE) for 6 years from 1982 to 1988, and trained several generations of plant taxonomists in China (Li,2001).  相似文献   
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