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乌鲁木齐南部山区森林生态系统树生地衣群落结构 总被引:1,自引:0,他引:1
为了探明乌鲁木齐南部山区树生地衣种类及其群落结构特征, 应用多元分析中的主成分分析及聚类分析方法, 对分布在乌鲁木齐南部山区森林生态系统中的树生地衣植物群落进行数量分类, 并对其群落结构的物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明, 分布在乌鲁木齐南部山区的树生地衣共有39种, 隶属于5目13科26属。根据多元分析结果, 将该地区的树生地衣划分为3种类型: (1) 小茶渍(Lecanora hageni (Ach.) Ach.) + 蜈蚣衣(Physcia stellaris (L.) Nyl.) + 柳茶渍(L. saligna (Schrad.) Zahlbr.)群落; (2) 斑面蜈蚣衣(Physcia aipolia (Humb.) Furm.) + 对开蜈蚣衣(Ph. dimidiata (Arn.) Nyl.) + 喇叭石蕊(Cladonia pyxidata (L.) Hoffm.)群落; (3) 拟石黄衣(Xanthoria fallax (Hepp) Arnold.) + 丽石黄衣(X. elegans (Link.) Th. Fr.)群落。群落3的多样性指数最大, 为1.509, 其次为群落2, 其多样性指数为1.109, 群落1的多样性指数最低, 为1.088。同时, 研究发现海拔高度和树种是影响乌鲁木齐南部山区森林生态系统树生地衣结构的两个重要因素。 相似文献
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目的:研究红果龙葵茎、叶的水和乙醇提取液对常见微生物的抑菌作用。方法:制备红果龙葵茎和叶的水和乙醇提取液,用平板打孔法测定抑菌圈的方法,测定提取液对5种细菌的抑菌作用。结果和结论:红果龙葵茎和叶的水提取液和乙醇提取液对5种细菌有明显的抑制作用,乙醇提取液对5种细菌的抑菌作用强于水提取液;各提取液都显示出最低抑菌浓度和最低杀菌浓度。 相似文献
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Subcutaneous injection of zinc as sulphate to rats activates sigma-aminolaevulinic acid dehydratase (ALA-D) in red blood cells within few days of injection. This activation counteracts the inhibitory effect of orally administered ethanol. 相似文献
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Wagdy M. Eldehna Rofaida Salem Zainab M. Elsayed Tarfah Al-Warhi Hamada R. Knany Rezk R. Ayyad Thamer Bin Traiki Maha-Hamadien Abdulla Rehan Ahmad Hatem A. Abdel-Aziz Radwan El-Haggar 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1424
In the current work, a new set of carbohydrazide linked benzofuran-isatin conjugates (5a–e and 7a–i) was designed and synthesised. The anticancer activity for compounds (5b–d, 7a, 7b, 7d and 7g) was measured against NCI-55 human cancer cell lines. Compound 5d was the most efficient, and thus subjected to the five-dose screen where it showed excellent broad activity against almost all tested cancer subpanels. Furthermore, all conjugates (5a–e and 7a–i) showed a good anti-proliferative activity towards colorectal cancer SW-620 and HT-29 cell lines, with an excellent inhibitory effect for compounds 5a and 5d (IC50 = 8.7 and 9.4 µM (5a), and 6.5 and 9.8 µM for (5d), respectively). Both compounds displayed selective cytotoxicity with good safety profile. In addition, both compounds provoked apoptosis in a dose dependent manner in SW-620 cells. Also, they significantly inhibited the anti-apoptotic Bcl2 protein expression and increased the cleaved PARP level that resulted in SW-620 cells apoptosis. 相似文献
77.
Goralski KB Abdulla D Sinal CJ Arsenault A Renton KW 《American journal of physiology. Gastrointestinal and liver physiology》2005,289(3):G434-G443
Central nervous system (CNS) infection and inflammation severely reduce the capacity of cytochrome P-450 metabolism in the liver. We developed a mouse model to examine the effects of CNS inflammation on hepatic cytochrome P-450 metabolism. FVB, C57BL/6, and C3H/HeouJ mice were given Escherichia coli LPS (2.5 microg) by intracerebroventricular (ICV) injection. The CNS inflammatory response was confirmed by the elevation of TNF-alpha and/or IL-1beta proteins in the brain. In all mouse strains, LPS produced a 60-70% loss in hepatic Cyp3a11 expression and activity compared with saline-injected controls. Adrenalectomy did not prevent the loss in Cyp3a11 expression or activity, thereby precluding the involvement of the hypothalamic-adrenal-pituitary axis. Endotoxin was detectable (1-10 ng/ml) in serum between 15 and 120 min after ICV dosing of 2.5 microg LPS. Peripheral administration of 2.5 microg LPS by intraperitoneal injection produced similar serum endotoxin levels and a similar loss (60%) in Cyp3a11 expression and activity in the liver. The loss of Cyp3a11 in response to centrally or peripherally administered LPS could not be evoked in Toll-like receptor-4 (TLR4)-mutant (C3H/HeJ) mice, indicating that TLR4 signaling pathways are directly involved in the enzyme loss. In summary, we conclude that LPS is transferred from the brain to the circulation in significant quantities in a model of CNS infection or inflammation. Subsequently, LPS that has reached the circulation stimulates a TLR4-dependent mechanism in the periphery, evoking a reduction in Cyp3a11 expression and metabolism in the liver. 相似文献
78.
Hargunani R Al-Dujaily S Abdulla A Osborne D 《International Seminars in Surgical Oncology : ISSO》2005,2(1):4
Haematuria is a classical symptom of urological disease often signifying a primary bladder cancer. Rarely, however, the presence of blood in the urine can be due to secondary spread of tumours into the bladder from distant sites. Notably this has been reported to occur in breast cancer, malignant melanoma and gastric cancers. Haematuria due to spread from a primary oesophageal cancer to the bladder has never been reported. We present a case of haematuria confirmed histologically to be due to metastases from a primary oesophageal tumour. Oesophageal cancer is capable of spread to all three neighbouring compartments (abdomen, chest and neck) and therefore has the potential to spread to unusual sites. Clinicians should always carefully regard haematuria in a patient previously treated for cancer and retain a high index of suspicion for distant metastases as being the cause. 相似文献
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OBJECTIVE: To evaluate the possibility of replacing histologic biopsy of azoospermic testes by fine needle aspiration (FNA) for diagnostic and management purposes. STUDY DESIGN: Twenty-seven patients were examined under general anesthesia, and 53 testes were biopsied by FNA. Fifty-four testes were biopsied for histologic examination. Histology and cytology of each testis were compared to assess the discrepancy or concordance between the diagnoses. RESULTS: Twenty-seven testes showed complete concordance of cytology and histology, and 13 testes showed a mild degree of discrepancy. A severe degree of discrepancy was seen in 13 testes. In the majority of discrepant cases, FNA biopsy diagnosis was more sensitive in detecting evidence of full or advanced maturation. In one case of discrepancy, the histologic finding was Sertoli cells only, and cytology revealed focal full maturation. In vitro fertilization using sperm from this case was successful. CONCLUSION: FNA biopsy of testes in azoospermia is a fast, reliable and minimally traumatic method. The prospects for utilizing FNA biopsy material in assisted and microassisted fertilization are promising. 相似文献