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1.
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Abstract. The species of Apocephalus , subgenus Mesophora , are revised and twenty-eight species are recognized, including the following twenty-two new to science: from the Nearctic Region A. brunnipes, A. gemursus, A. pristinus, A. setialvus and A. unitarsus , and from the Neotropical Region A. absentis, A. adustus, A. anfractus, A. angustistylus, A. bisetus, A. brevicercus, A. curtus, A. gracilis, A. hansoni, A. leptotarsus, A. longistylus, A. micrepelis, A. moraviensis, A. prolatus, A. trisetus, A. tritarsus and A. truncaticercus. Additionally, three species known only from female specimens are described but not formally named. A lectotype is designated for A. mortifer Borgmeier, and immature stages of A. borealis, A. antennatus and A. mortifer are described. Unlike larvae of other Apocephalus species, all of which are parasites of ants (Hymenoptera: Formicidae), those of Mesophora species are parasites of various other hosts.  相似文献   

3.
The aim of the study was to verify the similarity of 13 species and 5 cultivars of ornamental alliums and classify them into groups based on morphological and isozyme variation. The work embraced: Allium aflatunense, A. caeruleum, A. christophii, A. giganteum, A. karataviense, A. moly, A. nigrum, A. pyrenaicum, A. rosenbachianum, A. schubertii, A. siculum (syn. Nectaroscordum siculum), A. sphaerocephalon, A. strictum, A. stipitatum 'Album', A. 'Ivory Queen', A. 'Lucy Ball', A. 'Mont Blanc', and A. 'Purple Sensation'. Scape length, inflorescence diameter, and flowering period were recorded. Isozyme marker polymorphism was assessed by starch gel electrophoresis. Eight polymorphic isozyme systems (AAT, GPI, PGM, ALAT, ACP, DIAP, ALDO, PGD) were selected from 16 analysed in the taxa. Besides the differences between the taxa, the isozymes revealed intraspecific polymorphism in 5 systems. A total of 37 markers were obtained and used for dendrogram construction. The most similar taxa were A. karataviense with A. 'Ivory Queen', and A. karataviense with A. christophii (similarity level 0.78). A high similarity of 11 taxa belonging to one group (A. aflatunense, A. christophii, A. giganteum, A. karataviense, A. nigrum, A. schubertii, A. 'Ivory Queen', A. 'Lucy Ball', A. stipitatum 'Album', A. 'Mont Blanc', A. 'Purple Sensation') suggested that this group could be identified with the subgenus Melanocrommyum.  相似文献   

4.
Abstract

The genus Amanita Pers. ex Fr. in Rome neighbourood. — The presence of the genus Amanita in Rome neighbourood, small district, with vegetation and soil diversified, has been studied. The list includes 30 entities (A. caesarea, A. argentea°, A. nivalis, A. vaginata, A. vaginata var. cinerea°, A. fulva, A. crocea°, A. umbrinolutea°, A. lividapallescens°, A. strangulata, A. junquillea, A. eliae°, A. muscaria, A. pantherina, A. alba, A. phalloides, A. phalloides var. alba, A. verna, A. virosa, A. citrina, A. citrina var. alba°, A. porphyria°, A. rubescens, A. spissa. A. excelsa, A. aspera, A. vittadini, A. codinae°, A. strobiliformis, A. boudieri°), 11 new also for latium (°), among these A. codinae and A. vaginata var. cinerea hitherto not found in Italy. At last, the genus in whole region is examined.  相似文献   

5.
Adenosine plays a role in regulating the contractile function of the heart. This includes a positive ionotropic action via the adenosine A(2A) receptor (A(2A)R) and an inhibition of beta(1)-adrenergic receptor-induced ionotropy (antiadrenergic action) via the adenosine A(1) receptor (A(1)R). Phosphatase activity has also been shown to influence contractile function by affecting the level of protein phosphorylation. Protein phosphatase 2A (PP2A) plays a significant role in mediating the A(1)R antiadrenergic effect. The purpose of this study was to investigate the effects of A(2A)R and A(1)R on the activities of PP2A in hearts obtained from wild-type (WT) and A(2A)R knockout (A(2A)R-KO) mice. PP2A activities were examined in myocardial particulate and cytoplasmic extract fractions. Treatment of wild-type hearts with the A(1)R agonist CCPA increased the total PP2A activity and increased the particulate:cytoplasmic PP2A activity ratio. Treatment with the A(2A)R agonist CGS-21680 (CGS) decreased the total PP2A activity and decreased the particulate:cytoplasmic PP2A activity ratio. This indicated a movement of PP2A activity between cell fractions. The effect of CCPA was inhibited by CGS. In A(2A)R-KO hearts the response to A(1)R activation was markedly enhanced whereas the response to A(2A)R activation was absent. These data show that A(2A)R and A(1)R regulate PP2A activity, thus suggesting an important mechanism for modulating myocardial contractility.  相似文献   

6.
The occurrence of indole alkaloids among secondary fungal metabolites was studied in species of the genus Aspergillus, isolated from soils that were sampled in various regions of Russia (a total of 102 isolates of the species A. niger, A. phoenicis, A. fumigatus, A. flavus, A. versicolor, A. ustus, A. clavatus, and A. ochraceus). Clavine alkaloids were represented by fumigaclavine, which was formed by A. fumigatus. alpha-Cyclopiazonic acid was formed by isolates of A. fumigatus, A. flavus, A. versicolor, A. phoenicis, and A. clavatus. The occurrence of indole-containing diketopiperazine alkaloids was documented for isolates of A. flavus, A. fumigatus, A. clavatus, and A. ochraceus. No indole-containing metabolites were found among the metabolites of A. ustus or A. niger.  相似文献   

7.
A new ribosomal protein of 38 kDa, named A0, was detected in yeast ribosomes on immunoblotting. The antibody used here was that against A1/A2, 13 kDa acidic ribosomal proteins which cross-reacted with A0. Although A0 and A1/A2 share common antigenic determinants, they differ in the following biochemical properties. While A1/A2 could be extracted from ribosomes with ethanol and ammonium sulfate, A0 could not. A0 gave two protein spots in a less acidic region than for A1/A2 on two-dimensional gel electrophoresis. The heterogeneity observed for A0 was ascribable to phosphorylation because one spot disappeared after treatment of the ribosomes with phosphatase. The syntheses of A0 and A1/A2 are directed by different mRNA species, as judged with a cell-free translation system, ruling out the possibility that A0 is a precursor of A1/A2. Although a mammalian ribosomal protein equivalent to A0 has been shown to be associated with 13 kDa acidic proteins in the cytoplasm, essentially no A0 was detected on immunoblotting in the yeast cytosol, while a small but detectable amount of A1/A2 was present. The possibility that A0 is a eukaryotic equivalent of L10 of Escherichia coli is discussed.  相似文献   

8.
报道了中国列蛾属Autosticha 33种昆虫,其中有23新种和中国3新纪录种.新种包括:连斑列蛾A.conjugiopuncla sp.nov.,茨坪列蛾A.cipingensis sp.nov.,小喜列蛾A.microphilodema sp.nov.,多斑列蛾A.maculosa sp.nov.,勐仑列蛾A.menglunica sp.nov.,粗鳞列蛾A.squarrosa sp.nov.,南昌列蛾A.nanchangensis sp.nov.,淡黄列蛾A.flavida sp.nov.,二瓣列蛾A.valvifida sp.nov.,复瓣列蛾A.complexivalvula sp.nov.,迷列蛾A.fallaciosa sp.nov.,直斑列蛾A.rectipunctata sp.nov.,齿瓣列蛾A.valvidentata sp.nov.,天目山列蛾A.tianmushana sp.nov.,异域列蛾A.heteramalla sp.nov.,沈氏列蛾A.shenaesp.nov,五峰列蛾A.wufengensis sp.nov.,奇异列蛾A.mirabilis sp.nov.,弓瓣列蛾A.arcivalvaris sp.nov.,刺列蛾A.oxyacantha sp.nov.,棒列蛾A.bacilliformis.sp.nov.,赤水列蛾A.chishuiensis sp. nov.和涉县列蛾A.shexianicasp.nov..中国新纪录种有:和列蛾A.modicella(Christoph,1882),粗点列蛾A.pachysticta(Meyrick,1936)和截列蛾A.truncicola Ueda,1997.此外,还报道了1个新组合--喜列蛾A.philodema(Meyrick,1938),comb.nov..文中提供了新种的外生殖器特征图.模式标本保存在南开大学生物系.  相似文献   

9.
Yu L  Huang Z  Mariani J  Wang Y  Moskowitz M  Chen JF 《Nature medicine》2004,10(10):1081-1087
Inactivation of the adenosine A(2A) receptor (A(2A)R) consistently protects against ischemic brain injury and other neural insults, but the relative contribution of A(2A)Rs on peripheral inflammatory cells versus A(2A)Rs expressed on neurons and glia is unknown. We created a chimeric mouse model in which A(2A)Rs on bone marrow-derived cells (BMDCs) were selectively inactivated or reconstituted by bone marrow transplantation. Selective reconstitution of A(2A)Rs on BMDCs (A(2A)R knockout mice transplanted with wild-type bone marrow cells) largely reinstates ischemic brain injury in global A(2A)R knockout mice. Conversely, selective inactivation of A(2A)Rs on BMDCs (wild-type mice transplanted with A(2A)R knockout bone marrow cells) attenuates infarct volumes and ischemia-induced expression of several proinflammatory cytokines in the brain, but exacerbates ischemic liver injury. These results indicate that the A(2A)R-stimulated cascade in BMDCs is an important modulator of ischemic brain injury and that ischemic brain and liver injuries are regulated distinctly by A(2A)Rs on BMDCs.  相似文献   

10.
The mechanism of action of the glutamate analogue α-aminoadipic (A A A) acid was investigated in terms of its toxicity to cultured astrocytes. A A A was more toxic to type 1 astrocytes than type 2 astrocytes. Also the higher toxicity of the L-isomer as compared to the D-isomer was seen on type 1 astrocytes but not type 2. The toxicity of A A A can be reduced by co-culture of type 1 astrocytes with microglia. This inhibition may be due to glutamate release by microglia. No such effect is seen for type 2 astrocytes. The major uptake route for A A A by type 1 astrocytes is through the sodium dependent glutamate port. Both isomers of A A A are toxic to dividing astrocytes. The D-isomer appears to be toxic only for mitotic cells. The mechanism of this toxicity is protein synthesis dependent. It is suggested that A A A is toxic to mitotic astrocytes by interference with protein synthesis needed for cell division. D-A A A as opposed to L-A A A may prove a valuable tool for investigation of astrocyte proliferation in development and disease.  相似文献   

11.
Based on mutagenesis and structural studies of human immunodeficiency virus (HIV) envelope proteins, the loop region of gp41 is thought to directly interact with gp120. The importance of the HIV gp41 loop region to envelope function has been systematically examined by alanine scanning of all gp41 loop residues and the subsequent characterization of the mutagenic effects on viral entry, envelope expression, envelope processing, and gp120 association with gp41. With respect to the wild-type gp41, mutational effects on viral entry fall into four classes as follows: 1) little or no effect (G594A, S599A, G600A, K601A, N611A, S615A, N616A, and L619A); 2) significantly reduced entry (I595A, L602A, I603A, V608A, and K617A); 3) abolished entry (L593A, W596A, G597A, T606A, W610A, W614A, S618A, and I622A); and 4) enhanced entry (T605A, P609A, S613A, E620A, and Q621A). The reduced functionality of many mutants was apparently due to either disruption of envelope processing (L593A and T606A), viral incorporation of the envelope (W610A, W614A, and I662A), or increased dissociation of gp120 (W596A, G597A, and S618A). The extreme sensitivity of the gp120-gp41 interaction to alanine substitutions (e.g. the G597A and S618A mutants are relatively conservative substitutions) suggests that this association is an attractive and novel target for future drug discovery efforts.  相似文献   

12.
Book reviewed in this article:
Vagrant Woman . A film by JOHN MARSHALL
A Forty Dollar Misunderstanding . A film by JOHN MARSHALL
Two Brothers . A film by JOHN MARSHALL
Wrong Kid . A film by JOHN MARSHALL
The Informant . A film by JOHN MARSHALL
After the Game . A film by JOHN MARSHALL
901/904 . A film by JOHN MARSHALL
An Investigation of a Hit and Run . A film by JOHN MARSHALL
A Legal Discussion of a Hit and Run . A film by JOHN MARSHALL
Nothing Hurt but My Pride . A film by JOHN MARSHALL
Youth and the Man of Property . A film by JOHN MARSHALL
Manifold Controversy . A film by JOHN MARSHALL
Appitsch and the Drunk . A film by JOHN MARSHALL
Henry is Drunk . A film by JOHN MARSHALL
T-Group . A film by JOHN MARSHALL
You Wasn't Loitering . A film by JOHN MARSHALL  相似文献   

13.
The human APOBEC3 family consists of seven cytidine deaminases (A3A to A3H), some of which display potent antiretroviral activity against HIV-1 and other retroviruses. Studies that analyzed the effect of A3G on human T-lymphotropic virus type 1 (HTLV-1) infectivity resulted in conflicting findings, and our knowledge of HTLV-1 restriction by other A3 proteins remains limited. Since HTLV-1, much like HIV, targets CD4(+) T cells, we hypothesized that A3 proteins other than A3G restrict HTLV-1. All seven human A3 proteins were tested in HTLV-1 reporter and HIV-1 infectivity assays. We show that A3A, A3B, and A3H haplotype 2 (A3H hapII) acted as potent inhibitors of HTLV-1. Wild-type HIV-1, in contrast, was restricted by A3B and A3H hapII, but not by A3A. Catalytic site mutants of A3A, A3B, and A3H hapII showed that A3A and A3B restriction of HTLV-1 required deaminase activity. However, A3H hapII acted in a deaminase-independent manner when restricting HTLV-1, while requiring deaminase activity for HIV-1 restriction. We also analyzed A3 editing of HTLV-1 in five T-cell lines obtained from HTLV-1-infected patients. These cell lines contained extensively edited HTLV-1 sequences with G-to-A mutations in dinucleotide contexts suggestive of APOBEC3 mutagenesis. Comparison of the A3-induced mutations from reporter cells and the patient-derived cell lines indicate that A3G but also other A3 members, possibly A3A and A3B, affect HTLV-1 in vivo. Taken together, our data indicate that HTLV-1 is a likely target for multiple A3 proteins.  相似文献   

14.
15.
We hypothesized that A2A adenosine receptor (A2A AR) activation causes vasorelaxation through cytochrome P-450 (CYP) epoxygenases and endothelium-derived hyperpolarizing factors, whereas lack of A2A AR activation promotes vasoconstriction through Cyp4a in the mouse aorta. Adenosine 5'-N-ethylcarboxamide (NECA; 10(-6) M), an adenosine analog, caused relaxation in wild-type A2A AR (A2A AR+/+; +33.99 +/- 4.70%, P < 0.05) versus contraction in A2A AR knockout (A2A AR(-/-); -27.52 +/- 4.11%) mouse aortae. An A2A AR-specific antagonist (SCH-58261; 1 microM) changed the NECA (10(-6) M) relaxation response to contraction (-35.82 +/- 4.69%, P < 0.05) in A2A AR+/+ aortae, whereas no effect was noted in A2A AR(-/-) aortae. Significant contraction was seen in the absence of the endothelium in A2A AR+/+ (-2.58 +/- 2.25%) aortae compared with endothelium-intact aortae. An endothelial nitric oxide synthase inhibitor (N-nitro-L-arginine methyl ester; 100 microM) and a cyclooxygenase inhibitor (indomethacin; 10 microM) failed to block NECA-induced relaxation in A2A AR+/+ aortae. A selective inhibitor of CYP epoxygenases (methylsulfonyl-propargyloxyphenylhexanamide; 10 microM) changed NECA-mediated relaxation (-22.74 +/- 5.11% at 10(-6) M) and CGS-21680-mediated relaxation (-18.54 +/- 6.06% at 10(-6) M) to contraction in A2A AR+/+ aortae, whereas no response was noted in A2A AR(-/-) aortae. Furthermore, an epoxyeicosatrienoic acid (EET) antagonist [14,15-epoxyeicosa-5(Z)-enoic acid; 10 microM] was able to block NECA-induced relaxation in A2A AR+/+ aortae, whereas omega-hydroxylase inhibitors (10 microM dibromo-dodecenyl-methylsulfimide and 10 microM HET-0016) changed contraction into relaxation in A2A AR(-/-) aorta. Cyp2c29 protein was upregulated in A2A AR+/+ aortae, whereas Cyp4a was upregulated in A2A AR(-/-) aortae. Higher levels of dihydroxyeicosatrienoic acids (DHETs; 14,15-DHET, 11,12-DHET, and 8,9-DHET, P < 0.05) were found in A2A AR+/+ versus A2A AR(-/-) aortae. EET levels were not significantly different between A2A AR+/+ and A2A AR(-/-) aortae. It is concluded that CYP epoxygenases play an important role in A2A AR-mediated relaxation, and the deletion of the A2A AR leads to contraction through Cyp4a.  相似文献   

16.
The calcium binding S100A8/A9 complex (MRP8/14; calgranulin) is considered as an important proinflammatory mediator in acute and chronic inflammation and has recently gained attention as a molecular marker up-regulated in various human cancers. Here, we report that S100A8/A9 is expressed in breast cancer cell lines and is up-regulated by interleukin-1beta and tumor necrosis factor-alpha in SKBR3 and MCF-7 cells. We identified the phospholipid-binding protein annexin A6 as a potential S100A8/A9 binding protein by affinity chromatography. This finding was verified by Southwestern overlay experiments and by coimmunoprecipitation with the S100A8/A9-specific monoclonal antibody 27E10. Immunocytochemical experiments demonstrated that S100A8/A9 and annexin A6 colocalize in SKBR3 breast cancer cells predominantly in membranous structures. Upon calcium influx both S100A8/A9 and annexin A6 are exposed on the cell surface of SKBR3 cells. Subcellular fractionation studies suggested that after A23187 stimulation membrane association of S100A8/A9 is not enhanced. However, both S100A8/A9 and annexin A6 are exposed on the cell surface of SKBR3 cells upon calcium influx. Experiments with artificial liposomes indicated that S100A8/A9 is able to associate with membranes independently of both annexin A6 and independently of calcium. Finally, cell surface expression of S100A8/A9 could not be observed in A23187-treated A431 and HaCaT cells. Both cell lines are known to be devoid of annexin A6. Repression of annexin A6 expression by small interfering RNA in SKBR3 cells abolishes the cell surface exposition of S100A8/A9 upon calcium influx, suggesting that annexin A6 contributes to the calcium-dependent cell surface exposition of the membrane associated-S100A8/A9 complex.  相似文献   

17.
18.
The genus Annesorhiza is revised and twelve species are recognized, of which two are newly described: A. altiscapa, A. burttii, A. flbrosa, A. flagellifolia, A. grandiflora, A. lateriflora, A. latifolia, A. macrocarpa, A. nuda, A. schlechteri, A. thunbergii and A. wilmsii. A. marlothii is reduced to synonymy under A. lateriflora , a species hitherto poorly known as Peucedanum lateriflorum. A. thunbergii is only known from the type specimen. A. elata, A. hirsuta and A. villosa are sunk under A. grandiflora. A. fúicaulis has recently been excluded from Annesorhiza on the basis of fruit structure. A key to the species is provided, an update on the nomenclature, typification of names and distribution maps are provided for all the species.  相似文献   

19.
We have compared the tryptic peptide fingerprints of the A alpha, A beta, E alpha, and E beta subunits encoded by four wild-derived H-2 complexes expressing A molecules closely related to Ak. The A molecules encoded by these Ak-related mice have A alpha and A beta subunits that differ from A alpha k and A beta k by less than 10% of their tryptic peptides. Comparisons among the four wild-derived A molecules suggested that these contemporary A alpha and A beta alleles arose by sequential mutational events from common ancestor A alpha and A beta alleles. These results suggest that A alpha and A beta may co-evolve as an A beta A alpha gene duplex in wild mice. Tryptic peptide fingerprint comparisons of the E beta gene linked to these Ak-related A beta A alpha gene duplexes indicate that two encode E beta d-like subunits, whereas another encodes an E beta s-like subunit. These results strongly suggest that the A beta A alpha duplex and E beta recombine in wild mouse populations. The significantly different evolutionary patterns exhibited by the class II genes encoding A vs E molecules are discussed.  相似文献   

20.
27-Oxomilbemycins A3 and A4 and 27-hydroxymilbemycins A3 and A4 were identified as metabolites in soil metabolism studies of milbemycins A3 and A4. Chemical derivation methods were developed to synthesize 27-oxomilbemycins A3 and A4 and 27-hydroxymilbemycins A3 and A4 from milbemycins A3 and A4. In addition, 27-alkoxymilbemycin derivatives were also synthesized from the same precursors. Some of the synthesized compounds displayed satisfactory acaricidal activity against the organophosphorus-sensitive two-spotted spider mite (Tetranychus urticae), but did not have superior activity to corresponding milbemycins A3 and A4.  相似文献   

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