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991.
芹菜化学成分及药理活性研究进展 总被引:24,自引:0,他引:24
介绍了芹菜的化学成分及药理活性研究概况。芹菜主要含有挥发油、脂肪酸和黄酮类等化学成分,具有抗菌杀虫、抗氧化、抗肿瘤及抗心血管疾病等药理活性。作为药食两用且广泛种植的植物,对其进行进一步的研究和开发具有重要的意义。 相似文献
992.
利用深层发酵培养基对两种食药用菌(香菇、猴头菌)进行深层发酵培养,然后分别将香菇(猴头菌)发酵滤液、奶粉、无菌水按不同比例配制成相应的复原奶,并接种乳酸菌制成酸乳。同时检测不同比例发酵滤液添加量所制得的酸乳的营养和理化特性,选择出了最佳比例的滤液添加量,即香菇滤液添加量以3份较好,而猴头菌则以4份滤液添加量最佳。 相似文献
993.
Comparative studies on histological and ultra-structure of the pituitary of different ploidy level fishes 总被引:4,自引:3,他引:1
Yu Long Shaojun Liu Weiren Huang Jian Zhang Yuandong Sun Chun Zhang Song Chen Jinghui Liu Yun Liu 《中国科学:生命科学英文版》2006,49(5):446-453
The histological and ultra-structure of the pituitary in diploid red crucian carp(Carassius auratus red var.),triploid crucian carp and allotetraploid hybrids within and after the breeding season were comparatively studied.The result showed that there were six endocrine cell types in the pituitary of these three kinds of fishes,and there was an obvious difference in cell size among different ploidy level fishes.As for the same type of pituitary cells,the cell size was increased gradually with the in- creasing ploidy level.In the breeding season,the allotetraploid hybrids had higher proportion of go- nadotropin cells(GTH)than triploids,and the triploids had higher proportion of GTH than diploids.The results were related to the earlier sexual maturity of allotetraploid hybrids and sterility of triploid cru- cian carp.On the other hand,among the three kinds of fishes,the proportion of somatotropin(STH) cells in triploids crucian carp was the highest,whereas that in allotetraploid hybrids was the lowest. The results might be connected with the faster growth rate of triploids and slower growth rate of al- lotetraploid hybrids.In addition,in GTH cells of meso-adenohypophysis after the breeding season, there were many endocrine particles in triploids,while those endocrine particles were released from the cells in allotetraploids and diploids.This result showed that the sterility of triploid crucian carp might be related to the hormone which was not released from the GTH cells.In a word,the present study indicated that the differences in the structure of pituitary among different ploidy level fishes contributed to their difference in the growth rate and gonadal development. 相似文献
994.
二倍体鲫鲤F2产生不同倍性卵子的证据 总被引:4,自引:0,他引:4
在检测到鲫鲤F2产生3种不同大小(直径分别为0.13 cm,0.17cm和0.2 cm)类型的卵子基础上,进行了F2(♀)×红鲫(♂)及F2(♀)×四倍体鲫鲤(♂)的交配实验.通过染色体计数和流式细胞仪分析,在F2(♀)×红鲫(♂)后代中获得了四倍体、三倍体、二倍体鱼;在F2(♀)×四倍体鲫鲤(♂)后代中获得了四倍体和三倍体鱼.这两个交配组合后代中出现的不同倍性的鱼类为证明鲫鲤F2能产生三倍体、二倍体和单倍体卵子提供了进一步证据.F2(♀)×红鲫(♂)中雄性四倍体鱼的存在说明在四倍体后代中存在基因型为XXXY的个体.对上述两个交配组合后代的四倍体鱼和三倍体鱼的性腺结构观察表明四倍体鱼是可育的,而三倍体鱼是不育的.作者认为鲫鲤F2能够产生二倍体和三倍体卵子与核内复制机制和生殖细胞的融合有关. 相似文献
995.
Lee S Min HG Choi SH Kim YJ Oh SW Kim YJ Park Y Kim SS 《Obesity (Silver Spring, Md.)》2006,14(1):172-179
Objective: Obesity‐related metabolic diseases may influence prostatic hyperplasia. This study examined the impact of obesity on prostate volume in men without overt obesity‐related metabolic diseases. Research Methods and Procedures: We recruited 146 men over the age of 40 years who did not have overt obesity‐related diseases, such as diabetes, impaired fasting glucose, hypertension, or dyslipidemia. Transrectal ultrasonography was performed on all subjects. The subjects were divided into three groups according to their BMI: normal (18.5 to 22.9 kg/m2), overweight (23 to 24.9 kg/m2), and obese (≥25 kg/m2), and two groups according to their waist circumference: normal waist (≤90 cm) and central obesity (>90 cm). The classification of the subgroups was based on the Asia‐Pacific criteria of obesity. We compared the prostate volume among subgroups and assessed factors related to prostatic hyperplasia. Results: Mean prostate volume was 18.8 ± 5.0, 21.8 ± 7.2, and 21.8 ± 5.6 mL in the normal, overweight, and obese groups, respectively, and was 20.0 ± 5.9 and 23.7 ± 5.3 mL in the normal waist and central obesity group, respectively. Prostate volume was significantly greater in the obese group than in the normal group (P = 0.03) and in the central obesity group compared with the normal waist group (P = 0.002). Prostate volume was positively correlated with BMI and waist circumference after adjustment for age. After adjusting for confounding factors, central obesity was an independent factor affecting prostatic hyperplasia, which was defined as a prostate volume >20 mL (odds ratio = 3.37, p = 0.037). Relative to men with both low BMI (18.5 to 22.9 kg/m2) and normal waist circumference, those with high BMI (≥25 kg/m2) and central obesity were at significantly increased risk of prostatic hyperplasia (odds ratio = 4.88, p = 0.008). However, those with high BMI (≥25 kg/m2) and normal waist circumference were not at significantly increased risk. Discussion: Prostate volume was greater in the obese and central obesity groups than in the normal group after patients with overt obesity‐related metabolic diseases were excluded. Although both BMI and waist circumference were positively correlated with prostate volume, central obesity was the only independent factor affecting prostate hyperplasia. We suggest that central obesity is an important risk factor for prostatic hyperplasia. 相似文献
996.
浅部真菌病1948份临床标本的真菌学分析 总被引:10,自引:2,他引:8
目的 通过对浅部真菌病患者临床送检标本的病原真菌菌种进行系统分析,了解感染及病原真菌的分布情况。方法 采用直接镜检、培养及真菌鉴定等方法对临床送验标本进行检验和鉴定,大部分标本鉴定到种。结果 1948份临床送验标本中,直接涂片镜检阳性率53.41%,培养阳性率40.28%,而镜检+培养的阳性率为66.98%。对上述3种方法的真菌检出率进行比较,均存在显著差异(χ^2检验P均〈0.005)。在培养的1944份标本中,共分离出18个属,36种真菌,其中,红色毛癣菌24.52%、须癣毛癣菌16.48%、白念珠菌12.64%。结论 ①镜检结合培养的阳性率显著高于单一的镜检或培养的阳性率。②在患者即时的真菌镜检阴性时,应选择培养方法进一步检测,不轻易排除浅部真菌病感染可能。③皮肤癣菌居患者浅部真菌病致病菌首位,而白念珠菌及酵母类菌也是重要病原菌。 相似文献
997.
目的:建立一种简单高效的中脑多巴胺神经元细胞原代培养方法,并观察胰酶消化对中脑多巴胺能神经元突起生长的损伤作用。方法:以Nakai等经典神经元细胞原代培养方法为基础,通过使用低日龄胎鼠,初次培养液加入胎牛血清等步骤,促进中脑多巴胺能神经元细胞贴壁和生长;在无胰酶消化组直接使用内口外翻的小口径硅化吸管轻柔吹打离散细胞,比较两种方法间神经元细胞突起形成的差异。结果:接吹打组其多巴胺能神经元细胞突起的生长程度(2124-10um)明显高于胰酶消化组(113+9μm)(P〈0.01),而两组间多巴胺阳性细胞比例未见显著差异(P〉0.05)。结论:在中脑多巴胺能神经元细胞原代培养中,低日龄胎鼠及免胰酶消化离散细胞可减少神经元细胞损伤,有利于细胞突起的生长。 相似文献
998.
999.
Song YS Lyngsø R Hein J 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2006,3(3):239-251
Given a set D of input sequences, a genealogy for D can be constructed backward in time using such evolutionary events as mutation, coalescent, and recombination. An ancestral configuration (AC) can be regarded as the multiset of all sequences present at a particular point in time in a possible genealogy for D. The complexity of computing the likelihood of observing D depends heavily on the total number of distinct ACs of D and, therefore, it is of interest to estimate that number. For D consisting of binary sequences of finite length, we consider the problem of enumerating exactly all distinct ACs. We assume that the root sequence type is known and that the mutation process is governed by the infinite-sites model. When there is no recombination, we construct a general method of obtaining closed-form formulas for the total number of ACs. The enumeration problem becomes much more complicated when recombination is involved. In that case, we devise a method of enumeration based on counting contingency tables and construct a dynamic programming algorithm for the approach. Last, we describe a method of counting the number of ACs that can appear in genealogies with less than or equal to a given number R of recombinations. Of particular interest is the case in which R is close to the minimum number of recombinations for D. 相似文献
1000.
Late embryogenesis abundant (LEA) proteins are closely associated with the tolerance of diverse stresses in organisms. To
elucidate the function of group 3 LEA proteins, the soybean PM2 protein (LEA3) was expressed in E. coli and the protective function of the PM2 protein was assayed both in vivo and in vitro. The results of a spot assay and survival
ratio demonstrated that the expression of the PM2 protein conferred the tolerance to the E. coli recombinant for different temperature conditions (4, −20 or 50°C) or high-salinity stresses (120 mmol/l MgCl2 or 120 mmol/l CaCl2). In addition, it was demonstrated that the in vitro addition of the PM2 protein could prevent the lactate dehydrogenase
(LDH) inactivation normally induced by freeze–thaw. In the 62°C condition, the PM2 protein (1:5 mass ratio to LDH) effectively
prevented the LDH thermo-denaturation by acting synergistically with trehalose (62.5 μg/ml), although the PM2 protein alone
at this concentration showed little protective effect on LDH activity. Furthermore, the results showed that the PM2 protein
could partially prevent the thermo-denaturation of the bacterial proteome after boiling for 2 min. Based on these results,
we propose that the PM2 protein itself, or together with trehalose, conferred the tolerance to the E. coli recombinant against diverse stresses by protecting proteins and enzyme activity under low- or high- temperature conditions. 相似文献