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羊肚菌Morchella esculenta是子囊菌亚门的一种大型药食两用真菌,具有重要的经济价值和药用价值。然而近年来全球气候变化,导致羊肚菌属物种的栖息地破碎和片段化,加上消费者对羊肚菌美食的喜爱,过渡采挖造成羊肚菌属野生资源急剧减少,因此,急需对羊肚菌属物种资源进行保护。遗传多样性的时空分布是保护生物学的重要内容,遗传多样性关系到一个物种或类群的进化潜力和未来命运。生物基因组和进化的研究能够辅助挖掘物种深层次的优异基因资源,有利于从本质上对物种进行科学保护。从羊肚菌属的遗传多样性、遗传结构和家系关系以及基因组进化等的研究进展进行综述,以期为羊肚菌属资源的科学保护提供重要依据。 相似文献
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丁香水溶性化学成分的研究 总被引:2,自引:0,他引:2
目的:研究丁香水溶性化学成分。方法:利用HP-20大孔吸附树脂、反相硅胶柱色谱、反相制备薄层色谱、制备型反相高效液相色谱进行分离,NMR和MS等方法进行结构鉴定。结果:从丁香干燥花蕾的水提物中分离鉴定了5个化合物,分别为槲皮素-3-O-葡萄糖醛酸苷(1),槲皮素-3-O-葡萄糖醛酸苷6″-甲酯(2),槲皮素-3-O-葡萄糖苷(3),丁香酚-β-芸香糖苷(4),杨梅酮(5)。结论:化合物1~4为首次从丁香属植物中分离得到。 相似文献
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[目的]评价蒙药胃舒安对束缚-水浸应激所致大鼠胃溃疡的预防作用。[方法]将Wistar实验大鼠,分正常组、给药组和对照组3组,正常组不给药,无束缚-水浸应激压力,对照组给淀粉,给药组灌胃给蒙药胃舒安,给药剂量为0.9~1.3mL/只(82.5g/L),连续给胃舒安7d后,停食24h,建立3h束缚-水浸应激性胃溃疡模型,取胃,肉眼观察胃黏膜损伤,用Image J图像分析法测定胃黏膜溃疡面积,并进行比较。用酶联免疫吸附测定法检测胃溃疡大鼠血清转化生长因子(TGF-β1)含量并进行比较。[结果]蒙药胃舒安对3h束缚-水浸应激所致大鼠胃溃疡形成有抑制作用。胃舒安组大鼠血清TGF-β1含量明显低于对照组。[结论]蒙药胃舒安对实验大鼠束缚-水浸应激3h所致胃溃疡的形成有显著抑制作用。 相似文献
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Daniel M. Caruso M.D. Andrew A. Kassir M.D. Ramon A. Robles M.D. Michael W. Gregory M.D. Ryan B. Tsujimura M.D. Peter Cheung M.D. Peter J. Ferrara M.D. 《Diseases of the colon and rectum》1996,39(11):1222-1226
Introduction: Sigmoid volvulus is a disease of the elderly who often have severe comorbid conditions that increase their operative risk and limit treatment options. Conservative treatment with decompression
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sigmoidoscopy with rectal tube placement has high success and recurrence rates. Surgical resection with primary anastomosis is the treatment of choice when decompression fails or if the volvulus recurs. Unfortunately, perioperative complications are frequent. Moreover, many patients with sigmoid volvulus are bedridden or incontinent of stool and do not benefit from extensive resection and maintenance of bowel continuity. METHODS: Twelve debilitated patients with sigmoid volvulus determined preoperatively to be poor candidates for laparotomy and reanastomosis were treated with a trephine stoma. Initially, each patient had decompression
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rigid sigmoidoscopy and rectal tube placement. Surgical intervention consisted of formation of a small hole (trephine) in the left lower quadrant. Through this hole, a sigmoid resection and end colostomy were performed. No midline laparotomy was required. RESULTS: Operative times and analgesia requirements were significantly decreased (P
=0.05) compared with patients who underwent formal laparotomy. Length of hospital stay, complication rates, and length of bowel resected were similar using either surgical technique. CONCLUSIONS: The trephine stoma procedure offers significantly shorter operative times, with decreased perioperative morbidity. For high operative risk or debilitated patients with sigmoid volvulus, resection with end colostomy using the trephine stoma technique is the procedure of choice.Presented at the meeting of the Zollinger Surgical Society, Columbus, Ohio, September 5 to 7, 1996. 相似文献
28.
Interactions between vascular endothelial cells and blood platelets have been investigated using a model microcirculation consisting of microcarrier beads colonized with human umbilical vein endothelial cells (HUVECs) and perfused with washed platelet suspensions. To simulate the effects of endothelial desquamation and exposure of subendothelium, fibrillar collagen in suspension was coinjected with the platelets. In this model, neither the passage of platelets alone nor collagen alone stimulated prostacyclin (PGI2) production by the HUVECs. Platelets activated by coinjection with collagen released thromboxane A2 (TXA2), and this was associated with the simultaneous production of PGI2 by the HUVECs. By means of double-isotope experiments with [3H]arachidonic acid (AA) incorporated into platelets and [14C]-AA into HUVECs, it was shown that all the PGI2 generated was derived from platelet AA and/or endoperoxides. This interpretation was strengthened by the finding that PGI2 production was not prevented by treatment of HUVECs with indomethacin followed by perfusion with collagen-stimulated platelets. AA metabolites in double-isotope label experiments were further characterized by reverse-phase chromatography, and it was shown that both cyclooxygenase and lipoxygenase products of the HUVECs were derived from platelet membrane lipid. Thrombin regularly produced transient PGI2 release, but showed rapid tachyphylaxis. Platelet-derived compounds including ADP, ATP, and platelet-activating factor (PAF) did not produce PGI2 release by HUVECs in this system. Thus, the transfer of AA and metabolites from collagen- stimulated platelets is likely to be the mechanism for PGI2 production in the context of minor degrees of endothelial desquamation. 相似文献
29.
N Senst M Llacuachaqui J Lubinski H Lynch S Armel S Neuhausen P Ghadirian P Sun SA Narod 《Clinical genetics》2013,84(1):43-46
The objective is to estimate the risk of breast cancer in women who carry a deleterious BRCA1 or BRCA2 mutation, according to parental origin of mutation. We conducted a cohort study of women with a BRCA1 mutation (n = 1523) or BRCA2 mutation (n = 369) who had not been diagnosed with breast or ovarian cancer. For each woman, the pedigree was reviewed and the origin of the mutation was assigned as probable paternal or maternal. The hazard ratio (HR) for developing breast cancer in the follow‐up period was estimated for women with a paternal mutation compared to a maternal mutation. The risk of breast cancer was modestly higher in women with a paternal BRCA1 mutation compared to women with a maternal BRCA1 mutation (HR = 1.46; 95% CI = 0.99–2.16) but the difference was not significant (p = 0.06). The parental mutation origin did not affect the risk in women with a BRCA2 mutation. Our results are consistent with the hypothesis that there is an increased risk of breast cancer among women with a paternally inherited BRCA1 mutation compared to a maternally inherited mutation. However, the data are not sufficiently compelling to justify different screening recommendations for the two subgroups. 相似文献
30.
MB Delatycki M Wolthuizen MA Aitken C Hickerton SA Metcalfe KJ Allen 《Clinical genetics》2013,84(3):286-289
Hereditary hemochromatosis (HH) is a common preventable disorder of iron overload that can result in liver cirrhosis and reduced lifespan. Most HH is due to homozygosity for the HFE p.C282Y substitution. We conducted a study of screening for p.C282Y in high schools where p.C282Y heterozygotes (CY) individuals were informed of their genotype by letter. We studied whether these individuals understood the implications of their genotype, whether this resulted in anxiety or reduced health perception and whether cascade testing was higher in families of CY than wild‐type homozygous (CC) individuals. We found 586 of 5757 (1 in 10) screened individuals were CY. One month after receiving their result, 83% correctly answered that they have one copy of p.C282Y. There was no adverse change in anxiety or health perception from prior to screening to 1 month after receiving results. Significantly more family members of CY individuals than CC individuals were informed about HH and had testing for HH. In conclusion, we found that informing CY individuals of their genotype does not increase anxiety and the implications are generally well understood. This leads to cascade testing in a minority of families. CY individuals should be informed of their genetic status when identified by population screening. 相似文献