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41.
Sleightholm L Zambre A Chanda N Afrasiabi Z Katti K Kannan R 《Inorganica chimica acta》2011,365(1):333-339
Reactions of [MCl2(tmeda)] (M = Cd or Hg; tmeda = N,N,N′,N′-tetramethylethylenediamine) with M′SeC5H3(R-3)N (R = H or Me) gave selenolate complexes of the general formula [M{SeC5H3(R-3)N}2(tmeda)n] (M/R/n = Cd/H/1 (1); Cd/Me/1 (2); Hg/H/1 (3) and Hg/Me/0 (4)). The complexes were characterized by elemental analysis, UV-Vis and NMR (1H, 13C, 77Se, 113Cd and 199Hg) spectroscopy. The crystal structures of {SeC5H3(Me-3)N}2, [M(SeC5H4N)2(tmeda)] (M = Cd or Hg) and [Hg{SeC5H3(Me-3)N}2] were established by single crystal X-ray diffraction. The complex, [Cd(SeC5H4N)2(tmeda)] comprises of an octahedral cadmium atom containing three chelating, two SeC5H4N and one tmeda, ligands. The corresponding mercury complex adopts a severely distorted tetrahedral configuration defined by the two-monodentate selenolate and chelating tmeda. The complex, [Hg{SeC5H3(Me-3)N}2] has a linear structure with monodentate selenolate ligand. The cadmium complexes undergo a two-step decomposition (TGA) leading to the formation of CdSe. Thermolysis of [Cd{SeC5H3(R-3)N}2(tmeda)n] in hexadecylamine (HDA)/tri-n-octylphosphineoxide (TOPO) yields CdSe nanoparticles, which were characterized by UV-Vis, XRD, SEM and TEM (in part). 相似文献
42.
Vidhan Jain Henry B Armah Jon E Tongren Renée M Ned Nana O Wilson Sara Crawford Pradeep K Joel Mrigendra P Singh Avinash C Nagpal AP Dash Venkatachalam Udhayakumar Neeru Singh Jonathan K Stiles 《Malaria journal》2008,7(1):1-15
Background
Knowledge on insecticide resistance in target species is a basic requirement to guide insecticide use in malaria control programmes. Malaria transmission in the Mekong region is mainly concentrated in forested areas along the country borders, so that decisions on insecticide use should ideally be made at regional level. Consequently, cross-country monitoring of insecticide resistance is indispensable to acquire comparable baseline data on insecticide resistance.Methods
A network for the monitoring of insecticide resistance, MALVECASIA, was set up in the Mekong region in order to assess the insecticide resistance status of the major malaria vectors in Cambodia, Laos, Thailand, and Vietnam. From 2003 till 2005, bioassays were performed on adult mosquitoes using the standard WHO susceptibility test with diagnostic concentrations of permethrin 0.75% and DDT 4%. Additional tests were done with pyrethroid insecticides applied by the different national malaria control programmes.Results
Anopheles dirus s.s., the main vector in forested malaria foci, was susceptible to permethrin. However, in central Vietnam, it showed possible resistance to type II pyrethroids. In the Mekong delta, Anopheles epiroticus was highly resistant to all pyrethroid insecticides tested. It was susceptible to DDT, except near Ho Chi Minh City where it showed possible DDT resistance. In Vietnam, pyrethroid susceptible and tolerant Anopheles minimus s.l. populations were found, whereas An. minimus s.l. from Cambodia, Laos and Thailand were susceptible. Only two An. minimus s.l. populations showed DDT tolerance. Anopheles vagus was found resistant to DDT and to several pyrethroids in Vietnam and Cambodia.Conclusion
This is the first large scale, cross-country survey of insecticide resistance in Anopheles species in the Mekong Region. A unique baseline data on insecticide resistance for the Mekong region is now available, which enables the follow-up of trends in susceptibility status in the region and which will serve as the basis for further resistance management. Large differences in insecticide resistance status were observed among species and countries. In Vietnam, insecticide resistance was mainly observed in low or transmission-free areas, hence an immediate change of malaria vector control strategy is not required. Though, resistance management is important because the risk of migration of mosquitoes carrying resistance genes from non-endemic to endemic areas. Moreover, trends in resistance status should be carefully monitored and the impact of existing vector control tools on resistant populations should be assessed. 相似文献43.
Sequence and structure of Brassica rapa chromosome A3 总被引:1,自引:0,他引:1
Jeong-Hwan Mun Soo-Jin Kwon Young-Joo Seol Jin A Kim Mina Jin Jung Sun Kim Myung-Ho Lim Soo-In Lee Joon Ki Hong Tae-Ho Park Sang-Choon Lee Beom-Jin Kim Mi-Suk Seo Seunghoon Baek Min-Jee Lee Ja Young Shin Jang-Ho Hahn Yoon-Jung Hwang Ki-Byung Lim Jee Young Park Jonghoon Lee Tae-Jin Yang Hee-Ju Yu Ik-Young Choi Beom-Soon Choi Su Ryun Choi Nirala Ramchiary Yong Pyo Lim Fiona Fraser Nizar Drou Eleni Soumpourou Martin Trick Ian Bancroft Andrew G Sharpe Isobel AP Parkin Jacqueline Batley Dave Edwards Beom-Seok Park 《Genome biology》2010,11(9):1-12
Background
The species Brassica rapa includes important vegetable and oil crops. It also serves as an excellent model system to study polyploidy-related genome evolution because of its paleohexaploid ancestry and its close evolutionary relationships with Arabidopsis thaliana and other Brassica species with larger genomes. Therefore, its genome sequence will be used to accelerate both basic research on genome evolution and applied research across the cultivated Brassica species.Results
We have determined and analyzed the sequence of B. rapa chromosome A3. We obtained 31.9 Mb of sequences, organized into nine contigs, which incorporated 348 overlapping BAC clones. Annotation revealed 7,058 protein-coding genes, with an average gene density of 4.6 kb per gene. Analysis of chromosome collinearity with the A. thaliana genome identified conserved synteny blocks encompassing the whole of the B. rapa chromosome A3 and sections of four A. thaliana chromosomes. The frequency of tandem duplication of genes differed between the conserved genome segments in B. rapa and A. thaliana, indicating differential rates of occurrence/retention of such duplicate copies of genes. Analysis of 'ancestral karyotype' genome building blocks enabled the development of a hypothetical model for the derivation of the B. rapa chromosome A3.Conclusions
We report the near-complete chromosome sequence from a dicotyledonous crop species. This provides an example of the complexity of genome evolution following polyploidy. The high degree of contiguity afforded by the clone-by-clone approach provides a benchmark for the performance of whole genome shotgun approaches presently being applied in B. rapa and other species with complex genomes. 相似文献44.
H Arslan A Aktaş E Elibol OBB Esener AP Türkmen KK Yurt 《Biotechnic & histochemistry》2016,91(4):277-282
Diclofenac sodium (DS) is used primarily to treat fever and to alleviate pain and inflammation. We investigated the effects of DS exposure during gestation on the testes of rat pups to investigate the safety of its use during the prenatal period. Pregnant rats were separated into control, saline, low dose, medium dose and high dose groups. DS was given between weeks 15 and 21 of gestation. Total numbers of spermatogonia and Sertoli cells were counted in the testes of 7-day-old male rats using the physical disector method. By the end of the study, the total number of Sertoli cells was decreased significantly in a dose dependent manner in the medium and high dose groups compared to controls. No significant differences were found in the total number of spermatogonia in the control, saline and low dose DS groups. Medium and high dose DS administration reduced the total number of spermatogonia compared to other groups. We suggest that prenatal administration of DS can cause deleterious effects on the testis development, especially in high doses. 相似文献
45.
Divya T. Kandala Nimmy Mohan Vivekanand A Sudheesh AP Reshmi G Rakesh S. Laishram 《Nucleic acids research》2016,44(2):811-823
Almost all eukaryotic mRNAs have a poly (A) tail at the 3′-end. Canonical PAPs (PAPα/γ) polyadenylate nuclear pre-mRNAs. The recent identification of the non-canonical Star-PAP revealed specificity of nuclear PAPs for pre-mRNAs, yet the mechanism how Star-PAP selects mRNA targets is still elusive. Moreover, how Star-PAP target mRNAs having canonical AAUAAA signal are not regulated by PAPα is unclear. We investigate specificity mechanisms of Star-PAP that selects pre-mRNA targets for polyadenylation. Star-PAP assembles distinct 3′-end processing complex and controls pre-mRNAs independent of PAPα. We identified a Star-PAP recognition nucleotide motif and showed that suboptimal DSE on Star-PAP target pre-mRNA 3′-UTRs inhibit CstF-64 binding, thus preventing PAPα recruitment onto it. Altering 3′-UTR cis-elements on a Star-PAP target pre-mRNA can switch the regulatory PAP from Star-PAP to PAPα. Our results suggest a mechanism of poly (A) site selection that has potential implication on the regulation of alternative polyadenylation. 相似文献
46.
Papakonstantinou E; Karakiulakis G; Eickelberg O; Perruchoud AP; Block LH; Roth M 《Glycobiology》1998,8(8):821-830
The formation of atherosclerotic lesions is characterized by invasion of
vascular smooth muscle cells (VSMC) into the tunica intima of the arterial
wall and subsequently by increased proliferation of VSMC, a process
apparently restricted to the intimal layer of blood vessels. Both events
are preceded by the pathological overexpression of several growth factors,
such as platelet-derived growth factor (PDGF) which is a potent mitogen for
VSMC and can induce their chemotaxis. PDGF is generally not expressed in
the normal artery but it is upregulated in atherosclerotic lesions. We have
previously shown that PDGF-BB specifically stimulates proliferating VSMC to
secrete a 340 kDa hyaluronic acid (HA-340). Here, we present evidence
regarding the biological functions of this glycan. We observed that HA-340
inhibited the PDGF-induced proliferation of human VSMC in a dose-dependent
manner and enhanced the PDGF-dependent invasion of VSMC through a basement
membrane barrier. These effects were abolished following treatment of
HA-340 with hyaluronidase. The effect of HA-340 on the PDGF-dependent
invasion of VSMC coincided with increased secretion of the 72-kDa type IV
collagenase by VSMC and was completely blocked by GM6001, a hydroxamic acid
inhibitor of matrix metalloproteinases. HA-340 did not exert any
chemotactic potency, nor did it affect chemotaxis of VSMC along a PDGF
gradient. In human atheromatic aortas, we found that HA- 340 is expressed
with a negative concentration gradient from the tunica media to the tunica
intima and the atheromatic plaque. Our findings suggest that HA-340 may be
linked to the pathogenesis of atherosclerosis, by modulating VSMC
proliferation and invasion.
相似文献
47.
S Çolakoğlu A Aktaş S Raimondo AP Türkmen BZ Altunkaynak E Odacı 《Biotechnic & histochemistry》2014,89(2):136-144
We investigated the effects of diclofenac sodium (DS) on development of the optic nerve in utero. Pregnant female rats were separated into three groups: control, saline treated and DS treated. Offspring of these animals were divided into 4-week-old and 20-week-old groups. At the end of the 4th and 20th weeks of postnatal life, the animals were sacrificed, and right optic nerves were excised and sectioned for ultrastructural and stereological analyses. We demonstrated that both DS and saline produced structural and morphometric changes in the total axon number and density of axons, but decreased the myelin sheath thickness in male optic nerves. All ultrastructural and morphometric features were well developed in 20-week-old rats. We showed that development of the optic nerve continues during the early postnatal period and that some compensation for exposure to deleterious agents in utero may occur during early postnatal life. 相似文献
48.
Background
Affymetrix High Density Oligonuclotide Arrays (HDONA) simultaneously measure expression of thousands of genes using millions of probes. We use correlations between measurements for the same gene across 6685 human tissue samples from NCBI's GEO database to indicated the quality of individual HG-U133A probes. Low correlation indicates a poor probe. 相似文献49.
Distribution of the molossinus allele of Sry, the testis-determining gene, in wild mice 总被引:3,自引:0,他引:3
Nagamine CM; Shiroishi T; Miyashita N; Tsuchiya K; Ikeda H; Takao N; Wu XL; Jin ML; Wang FS; Kryukov AP 《Molecular biology and evolution》1994,11(6):864-874
When the Y chromosome of the laboratory inbred mouse strain C57BL/6 (B6) is
replaced by the Y of certain strains of Mus musculus domesticus, testis
determination fails and all XY fetuses develop either as hermaphrodites or
XY females (XY sex reversal). This suggests the presence of at least two
alleles of Sry, the male-determining gene on the Y:M. m. domesticus and B6.
The B6 Y chromosome is derived from the Japanese house mouse, M. m.
molossinus and therefore carries a molossinus Sry allele. As a first step
to determine how the molossinus Sry allele evolved, its distribution
pattern was determined in wild mice. The cumulative data of 96 M. musculus
samples obtained from 58 geographical locations in Europe, North Africa,
and Asia show the molossinus Sry allele is restricted to Japan and the
neighboring Asian mainland and confirm that Japanese M. m. molossinus mice
were derived in part from a race of M. m. musculus from Korea or Manchuria.
Sry polymorphisms, as illustrated by the molossinus Sry allele, can serve
as molecular markers for studies on the evolution of wild M. musculus
populations and can help determine the role sex determination plays in
speciation.
相似文献
50.
Flávia C Rodrigues-Lisoni Paulo PeitlJr Alessandra Vidotto Giovana M Polachini José V Maniglia Juliana Carmona-Raphe Bianca R Cunha Tiago Henrique Caique F Souza Rodrigo AP Teixeira Erica E Fukuyama Pedro MichaluartJr Marcos B de Carvalho Sonia M Oliani Head Neck Genome Project GENCAPO Eloiza H Tajara 《BMC medical genomics》2010,3(1):14