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991.
海水中Cu、Zn离子对牟氏角毛藻生长的生态效应 总被引:1,自引:0,他引:1
研究了Cu、Zn离子对车氏角毛藻生长的生态效应.结果表明,Cu离子活度低于10-7.80mol·L-1时,角毛藻生长繁殖良好,其中以10-13.57~10-10.52mol·L-1为最好;Cu离子活度≥10-7.80mol·L-1时产生毒性.低Zn离子活度未表现出对车氏角毛藻的必需性,Zn离子活度>10-7.00mol·L-1时不利于生长繁殖.与Zn离子相比,牟氏角毛藻对Cu离子的毒性更为敏感. 相似文献
992.
A double staining method combining Ulex europaeus agglutinin I lectin (UEA-I) and collagen type IV staining was used to determine the capillary density and the number of capillaries
relative to different fibre types in human skeletal muscles. The result of this combined staining was compared with that of
other staining methods including amylase-periodic acid Schiff (PAS), UEA-I, anti-collagen type IV and anti-von Willebrand
factor. Muscle biopsy specimens, 12 from M. vastus lateralis and 6 from M. soleus, were obtained from 18 healthy young men. Compared with amylase-PAS staining, double staining showed a larger number of capillaries
surrounding type I (+9.6%), type IIA (+8.6%) and type IIB (+11.6%) fibres in the M. vastus lateralis specimens (P<0.001 for all differences). The capillary to fibre ratio (cap·fibre–1) and the capillary density (cap·mm–2) were 8.3% (P<0.002) and 7.9% (P<0.001) larger, respectively. In the M. soleus specimens, cap·fibre–1 and cap·mm–2 were 7.4 and 9.9% larger, respectively, by double staining compared with PAS staining. Further comparisons showed that the
cap·fibre–1 and cap·mm–2 obtained with double staining were similar to the values determined by the UEA-I staining, but greater than that measured
by the collagen type IV method. The double staining gave a more marked stain of capillaries and revealed muscle fibre borders
clearly, which is an advantage in studies that require comparisons between serial sections using computerised image analyses.
It is concluded that the double staining method is superior to either the UEA-I, collagen type IV or the traditional amylase-PAS
staining methods in analysing capillary density of normal human skeletal muscle.
Accepted: 17 October 1996 相似文献
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994.
Florian A. Lempp Bingqian Qu Yong-Xiang Wang Stephan Urban 《Journal of virology》2016,90(9):4827-4831
Hepatitis B virus (HBV) enters hepatocytes via its receptor, human sodium taurocholate cotransporting polypeptide (hNTCP). So far, HBV infection has been achieved only in human hepatic cells reconstituted with hNTCP and not in cells of mouse origin. Here, the first mouse liver cell line (AML12) which gains susceptibility to HBV upon hNTCP expression is described. Thus, HBV infection of receptor-expressing mouse hepatocytes does not principally require a human cofactor but can be triggered by endogenous murine determinants. 相似文献
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996.
Manel Ben Abdallah Fatma Karray Najla Mhiri Nan Mei Marianne Quéméneur Jean-Luc Cayol Gaël Erauso Jean-Luc Tholozan Didier Alazard Sami Sayadi 《Extremophiles : life under extreme conditions》2016,20(2):125-138
Prokaryotic diversity was investigated in a Tunisian salt lake, Chott El Jerid, by quantitative real-time PCR, denaturing gradient gel electrophoresis (DGGE) fingerprinting methods targeting the 16S rRNA gene and culture-dependent methods. Two different samples S1-10 and S2-10 were taken from under the salt crust of Chott El Jerid in the dry season. DGGE analysis revealed that bacterial sequences were related to Firmicutes, Proteobacteria, unclassified bacteria, and Deinococcus-Thermus phyla. Anaerobic fermentative and sulfate-reducing bacteria were also detected in this ecosystem. Within the domain archaea, all sequences were affiliated to Euryarchaeota phylum. Quantitative real-time PCR showed that 16S rRNA gene copy numbers of bacteria was 5 × 106 DNA copies g?1 whereas archaea varied between 5 × 105 and 106 DNA copies g?1 in these samples. Eight anaerobic halophilic fermentative bacterial strains were isolated and affiliated with the species Halanaerobium alcaliphilum, Halanaerobium saccharolyticum, and Sporohalobacter salinus. These data showed an abundant and diverse microbial community detected in the hypersaline thalassohaline environment of Chott El Jerid. 相似文献
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Evolutionary processes and cellular functions underlying divergence in Alexandrium minutum
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