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1.
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域  相似文献   

2.
《生物学杂志》2014,(5):I0001-I0001
1、《生物学杂志》是生命科学的综合性学术期刊,主要刊登动物、植物、微生物及生理、生化、遗传、生物技术、生物工程、分子生物学等生命科学领域的学术论文以及大中专院校生物教学等方面的经验介绍。主要栏目有:研究报告、综述与专论、技术方法、教学研究等。对反映国内外最新研究成果的论文、国家级自然科学基金资助的论文、获省、部级以上资助项目的科研成果论文将优先发表。  相似文献   

3.
第十一届国际化石刺丝胞与多孔类学术研讨会于2011年8月21—26日在比利时的列日大学召开。全球27个国家将近有100名代表出席会议。除了东道主比利时外,参加会议的有中国、俄罗斯、美国、英国、法国、加拿大、日本、澳大利亚、德国、意大利、荷兰、爱尔兰、西班牙、瑞士、奥地利、波兰、罗马尼亚、爱沙尼亚、  相似文献   

4.
《微生物学通报》2011,(11):1725
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域  相似文献   

5.
《微生物学通报》2011,(10):1601
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域  相似文献   

6.
桑粉虱形态研究   总被引:4,自引:0,他引:4  
研究描述了容易与杨梅粉虱混淆的重要害虫桑粉虱Pealius mori(Takahashi)成虫、卵、1~4龄若虫及蛹的形状、分类特征,包括成虫的体长、体色、触角、单眼、复眼、口器、翅、足及雌雄外生殖器;卵的形状、大小、卵色及卵柄;1~4龄若虫及蛹的形状、大小、体色、体周的刚毛、触角、口器、足、管状孔、盖瓣、舌状器及腹沟等。并比较桑粉虱与杨梅粉虱的主要分类特征。  相似文献   

7.
微生物生物技术(或称微生物技术)是一门以应用微生物学为主体的综合性技术群,主要包括微生物学、生物化学、遗传学及基因工程、细胞工程、酶工程、发酵工程和生化工程等。从纵向划分,包括研究、发展和生产。利用微生物技术生产的产品包括酒类、调味品、有机溶剂、有机酸、氨基酸、维生素、抗生素、甾体激素、酶制剂、活性肽及蛋白、酵母及其它单细胞蛋白、淀粉糖等。应用范围包括食品、轻工、医药、农业、化工、矿业和环境保护等方面。  相似文献   

8.
《植物杂志》2010,(10):30-31
1.黄瓜:黄瓜原产于印度,又叫青瓜、胡瓜、刺瓜等,其性平、味甘,具有明显的清热解毒、生津止渴等功效。黄瓜中富含蛋白质、糖类、维生素B2、维生素C、维生素E、胡萝卜素、尼克酸、钙、磷、铁等营养成分,同时还含有丙醇二酸、葫芦素、柔软的细纤维等成分,是难得的排毒养颜佳品。  相似文献   

9.
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米  相似文献   

10.
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域的研究成果,以及该领域学科的热点难点问题,充分发挥《微生物学通报》的学科引领和导向作用,促进学  相似文献   

11.
In the past, the floristic diversity of arable fields has been described in terms of species diversity (SD) and their degree of coverage (C), but never in combination with the recording of the actually flowered species (FS) and their flowering intensity (FI) to striking differences in the cultivation methods on arable land. In relation to SD and C, however, FS and FI may provide important additional information on the functional biodiversity of fields. The aim was therefore to investigate the effects of (a) conventional, (b) organic, and (c) smallholder (never application of herbicides) on the floristic diversity. Using a region in Germany, we investigated SD, C, FS, and FI synchronously in (a), (b), and (c), by 356 vegetation surveys (5 × 5 m plots) conducted in spring and summer in 2019 in winter cereals. Statistical tests were used to analyze the differences between (a), (b), and (c). The medians were used to compare the floristic diversity of (a), (b), and (c) and finally relationships of FS and FI to SD were analyzed in relation to the cultivation methods. Significant differences in SD, C, FS, and FI were found between the (a), (b), and (c) in spring and summer characterized by sharp declines from (c) to (b) to (a). A drastic reduction in floristic diversity from (c) 100 to (b) 52 to (a) 3 was determined. Plants in flower (FS, FI) were very poorly in (a), moderately well to well in (b), and well to very well represented in (c). (C) to (a) was characterized by a sharp decline and from (a) to (b) by sharp increase in floristic diversity. With current acreage proportions of (a) in mind, this would affect, about one third of land area in Germany, associated with a drastic reduction in functional biodiversity for insects.  相似文献   

12.
alpha(v)beta(3) integrin has a dual role in apoptosis. Whereas ligated alpha(v)beta(3) activates cell survival pathways and suppresses pro-apoptotic signals, unligated alpha(v)beta(3) or integrins bound to soluble ligands promote apoptosis. In this study, we assessed the role of alpha(v)beta(3) in chemosensitivity of breast cancer cells expressing different levels of heregulin (HRG). Expression levels of the RGD-binding integrins alpha(v)beta(3) were measured in MDA-MB-231 human breast cancer cells and its low HRG-expressing derivative (MDA-MB-231/AS31) treated with the microtubule-interfering agents (MIAs) paclitaxel and vincristine. Following treatment, only alpha(v)beta(3) levels were significantly increased in MDA-MB-231 cells. Interestingly, alpha(v)beta(3) expression was more significantly up-regulated in the MDA-MB-231/AS31 cells than in the parental cells. This MIA-induced increase of alpha(v)beta(3) expression was correlated with a decrease in cell viability and an increase in apoptosis in MDA-MB-231/AS31 cells, indicating that overexpression of alpha(v)beta(3) is linked to chemotherapy-induced cell death in low HRG-expressing breast cancer models. Moreover, a paclitaxel-induced increase of alpha(v)beta(3) was also observed in MCF-7 cells but not in an doxorubicin-resistant derivative that shows cross-resistance to paclitaxel, further providing evidence that the extent of alpha(v)beta(3) up-regulation is related to cell damage. These results indicate that alpha(v)beta(3) integrin is dramatically up-regulated in low HRG-expressing breast cancer models that are highly responsive to MIAs, thus providing a novel molecular marker of chemosensitivity influenced by HRG levels in breast cancer cells.  相似文献   

13.
The rapid, non-genomic actions of 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] have been well described, however, the role of the nuclear vitamin D receptor (VDR) in this pathway remains unclear. To address this question, we used VDR(+/+) and VDR(-/-) osteoblasts isolated from wild-type and VDR null mice to study the increase in intracellular calcium ([Ca(2+)](i)) and activation of protein kinase C (PKC) induced by 1,25(OH)(2)D(3). Within 1 min of 1,25(OH)(2)D(3) (100 nM) treatment, an increase of 58 and 53 nM in [Ca(2+)](i) (n = 3) was detected in VDR(+/+) and VDR(-/-) cells, respectively. By 5 min, 1,25(OH)(2)D(3) caused a 2.1- and 1.9-fold increase (n = 6) in the phosphorylation of PKC substrate peptide acetylated-MBP(4-14) in VDR(+/+) and VDR(-/-) osteoblasts. The 1,25(OH)(2)D(3)-induced phosphorylation was abolished by GF109203X, a general PKC inhibitor, in both cell types, confirming that the secosteroid induced PKC activity. Moreover, 1,25(OH)(2)D(3) treatment resulted in the same degree of translocation of PKC-alpha and PKC-delta, but not of PKC-zeta, from cytosol to plasma membrane in both VDR(+/+) and VDR(-/-) cells. These experiments demonstrate that the 1,25(OH)(2)D(3)-induced rapid increases in [Ca(2+)](i) and PKC activity are neither mediated by, nor dependent upon, a functional nuclear VDR in mouse osteoblasts. Thus, VDR is not essential for these rapid actions of 1,25(OH)(2)D(3) in osteoblasts.  相似文献   

14.
2007-2008年,采用氯仿熏蒸浸提法测定了落叶松和水曲柳人工林土壤微生物生物量,研究施N肥对土壤微生物生物量碳、氮,以及细菌、真菌和放线菌数量季节变化的影响.结果表明:落叶松林地土壤微生物生物量碳、氮两年平均值分别比水曲柳林地低13.8%和18.3%,但两种林分土壤微生物生物量碳、氮具有相同的季节变化规律:5月最低,9月最高;表层(0~10 cm)土壤微生物生物量碳、氮及微生物数量均高于亚表层(10~20 cm)土壤.但细菌、真菌和放线菌数量的季节变化格局与生物量不同.施肥降低了两种林分的微生物生物量碳、氮,以及细菌、真菌和放线菌数量,其中,落叶松林地微生物生物量碳和氮分别降低了24%和63%,水曲柳分别降低了51%和68%.说明施N肥限制了土壤微生物生物量,改变了土壤微生物的群落结构.  相似文献   

15.
The role of hydrogen peroxide (H(2)O(2)) in abscisic acid (ABA)-induced anthocyanin accumulation in detached and intact leaves of rice seedlings was investigated. Treatment with ABA resulted in an accumulation of anthocyanins in detached rice leaves. Dimethylthiourea, a chemical trap for H(2)O(2), was observed to be effective in inhibiting ABA-induced accumulation of anthocyanins. Inhibitors of NADPH oxidase (diphenyleneiodonium chloride and imidazole), phosphatidylinositol 3-kinase (wortmannin and LY 294002), and a donor of nitric oxide (N-tert-butyl-alpha-phenylnitrone), which have previously been shown to prevent ABA-induced H(2)O(2) accumulation in detached rice leaves, inhibited ABA-induced anthocyanin increase. Exogenous application of H(2)O(2), however, was found to increase the anthocyanin content of detached rice leaves. In terms of H(2)O(2) accumulation, intact (attached) leaves of rice seedlings of cultivar Taichung Native 1 (TN1) are ABA sensitive and those of cultivar Tainung 67 (TNG67) are ABA insensitive. Upon treatment with ABA, H(2)O(2) and anthocyanins accumulated in leaves of TN1 seedlings but not in leaves of TNG67. Our results, obtained from detached and intact leaves of rice seedlings, suggest that H(2)O(2) is involved in ABA-induced anthocyanin accumulation in this species.  相似文献   

16.
Amino acid residues on PotB and PotC involved in spermidine uptake were identified by random and site-directed mutagenesis. It was found that Trp(8), Tyr(43), Trp(100), Leu(110), and Tyr(261) in PotB and Trp(46), Asp(108), Glu(169), Ser(196), Asp(198), and Asp(199) in PotC were strongly involved in spermidine uptake and that Tyr(160), Glu(172), and Leu(274) in PotB and Tyr(19), Tyr(88), Tyr(148), Glu(160), Leu(195), and Tyr(211) in PotC were moderately involved in spermidine uptake. Among 11 amino acid residues that were strongly involved in spermidine uptake, Trp(8) in PotB was important for insertion of PotB and PotC into membranes. Tyr(43), Trp(100), and Leu(110) in PotB and Trp(46), Asp(108), Ser(196), and Asp(198) in PotC were found to be involved in the interaction with PotD. Leu(110) and Tyr(261) in PotB and Asp(108), Asp(198), and Asp(199) in PotC were involved in the recognition of spermidine, and Trp(100) and Tyr(261) in PotB and Asp(108), Glu(169), and Asp(198) in PotC were involved in ATPase activity of PotA. Accordingly, Trp(100) in PotB was involved in both PotD recognition and ATPase activity, Leu(110) in PotB was involved in both PotD and spermidine recognition, and Tyr(261) in PotB was involved in both spermidine recognition and ATPase activity. Asp(108) and Asp(198) in PotC were involved in PotD and spermidine recognition as well as ATPase activity. These results suggest that spermidine passage from PotD to the cytoplasm is coupled to the ATPase activity of PotA through a structural change of PotA by its ATPase activity.  相似文献   

17.
The alpha(1c) subunit of the cardiac L-type Ca(2+) channel, which contains the channel pore, voltage- and Ca(2+)-dependent gating structures, and drug binding sites, has been well studied in heterologous expression systems, but many aspects of L-type Ca(2+) channel behavior in intact cardiomyocytes remain poorly characterized. Here, we develop adenoviral constructs with E1, E3 and fiber gene deletions, to allow incorporation of full-length alpha(1c) gene cassettes into the adenovirus backbone. Wild-type (alpha(1c-wt)) and mutant (alpha(1c-D-)) Ca(2+) channel adenoviruses were constructed. The alpha(1c-D-) contained four point substitutions at amino acid residues known to be critical for dihydropyridine binding. Both alpha(1c-wt) and alpha(1c-D-) expressed robustly in A549 cells (peak L-type Ca(2+) current (I(CaL)) at 0 mV: alpha(1c-wt) -9.94+/-1.00pA/pF, n=9; alpha(1c-D-) -10.30pA/pF, n=12). I(CaL) carried by alpha(1c-D-) was markedly less sensitive to nitrendipine (IC(50) 17.1 microM) than alpha(1c-wt) (IC(50) 88 nM); a feature exploited to discriminate between engineered and native currents in transduced guinea-pig myocytes. 10 microM nitrendipine blocked only 51+/-5% (n=9) of I(CaL) in alpha(1c-D-)-expressing myocytes, in comparison to 86+/-8% (n=9) of I(CaL) in control myocytes. Moreover, in 20 microM nitrendipine, calcium transients could still be evoked in alpha(1c-D-)-transduced cells, but were largely blocked in control myocytes, indicating that the engineered channels were coupled to sarcoplasmic reticular Ca(2+) release. These alpha(1c) adenoviruses provide an unprecedented tool for structure-function studies of cardiac excitation-contraction coupling and L-type Ca(2+) channel regulation in the native myocyte background.  相似文献   

18.
Hemoglobin zeta(2)beta(2)(S) is generated by substituting embryonic zeta-globin subunits for the normal alpha-globin components of Hb S (alpha(2)beta(2)(S)). This novel hemoglobin has recently been shown to inhibit polymerization of Hb S in vitro and to normalize the pathological phenotype of mouse models of sickle cell disease in vivo. Despite its promise as a therapeutic tool in human disease, however, the basic O(2)-transport properties of Hb zeta(2)beta(2)(S) have not yet been described. Using human hemoglobins purified from complex transgenic-knockout mice, we show that Hb zeta(2)beta(2)(S) exhibits an O(2) affinity as well as a Hill coefficient, Bohr response, and allosteric properties in vitro that are suboptimally suited for physiological O(2) transport in vivo. These data are substantiated by in situ analyses demonstrating an increase in the O(2) affinity of intact erythrocytes from mice that express Hb zeta(2)beta(2)(S). Surprisingly, though, co-expression of Hb zeta(2)beta(2)(S) leads to a substantial improvement in the tissue oxygenation of mice that model sickle cell disease. These analyses suggest that, in the context of sickle cell disease, the beneficial antisickling effects of Hb zeta(2)beta(2)(S) outweigh its O(2)-transport liabilities. The potential structural bases for the antisickling properties of Hb zeta(2)beta(2)(S) are discussed in the context of these new observations.  相似文献   

19.
Vacuolar-type rotary H(+)-ATPase/synthase (V(o)V(1)) from Thermus thermophilus, composed of nine subunits, A, B, D, F, C, E, G, I, and L, has been reconstituted from individually isolated V(1) (A(3)B(3)D(1)F(1)) and V(o) (C(1)E(2)G(2)I(1)L(12)) subcomplexes in vitro. A(3)B(3)D and A(3)B(3) also reconstituted with V(o), resulting in a holoenzyme-like complexes. However, A(3)B(3)D-V(o) and A(3)B(3)-V(o) did not show ATP synthesis and dicyclohexylcarbodiimide-sensitive ATPase activity. The reconstitution process was monitored in real time by fluorescence resonance energy transfer (FRET) between an acceptor dye attached to subunit F or D in V(1) or A(3)B(3)D and a donor dye attached to subunit C in V(o). The estimated dissociation constants K(d) for V(o)V(1) and A(3)B(3)D-V(o) were ~0.3 and ~1 nm at 25 °C, respectively. These results suggest that the A(3)B(3) domain tightly associated with the two EG peripheral stalks of V(o), even in the absence of the central shaft subunits. In addition, F subunit is essential for coupling of ATP hydrolysis and proton translocation and has a key role in the stability of whole complex. However, the contribution of the F subunit to the association of A(3)B(3) with V(o) is much lower than that of the EG peripheral stalks.  相似文献   

20.
J. Neurochem. (2012) 122, 1095-1107. ABSTRACT: Ca(2+) channel β subunits determine the maturation, biophysical properties and cell surface expression of high voltage-activated channels. Thus, we have analysed the expression, regional distribution and subcellular localization of the Ca(v) β subunit family in mice from birth to adulthood. In the hippocampus and cerebellum, Ca(v) β(1) , Ca(v) β(3) and Ca(v) β(4) protein levels increased with age, although there were marked region- and developmental stage-specific differences in their expression. Ca(v) β(1) was predominantly expressed in the strata oriens and radiatum of the hippocampus, and only weakly in the cerebellum. The Ca(v) β(3) subunit was mainly expressed in the strata radiatum and lucidum of the hippocampus and in the molecular layer of the cerebellum. During development, Ca(v) β(3) protein expression in the cerebellum peaked at postnatal days (P) 15 and 21, and had diminished drastically by P60, and in the hippocampus increased with age throughout all subfields. Ca(v) β(4) protein was detected throughout the cerebellum, particularly in the molecular layer, and in contrast to the other subunits, Ca(v) β(4) was mainly detected in the molecular layer and the hilus of the hippocampus. At the subcellular level, Ca(v) β(1) and Ca(v) β(3) were predominantly located post-synaptically in hippocampal pyramidal cells and cerebellar Purkinje cells. Ca(v) β(4) subunits were detected in the pre-synaptic and post-synaptic compartments of both regions, albeit more strongly at post-synaptic sites. These results shed new light on the developmental regulation and subcellular localization of Ca(v) β subunits, and their possible role in pre- and post-synaptic transmission.  相似文献   

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