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91.
Lubna Bilal Sajjad Asaf Muhammad Hamayun Humaira Gul Amjad Iqbal Ihsan Ullah In-Jung Lee Anwar Hussain 《Symbiosis (Philadelphia, Pa.)》2018,76(2):117-127
Endophytes can serve as plant growth promoters as they secret a vast array of phytohormones to support host plants. Keeping the growth promoting activity of the endophytes in view, two endophytic fungi, Asprgillus fumigatus TS1 and Fusarium proliferatum BRL1 have been isolated from the roots of Oxalis corniculata. The isolates have been screened initially for growth promoting activities, including siderophores activity, phosphate solubilization, and secreation of indole acetic acid and gibberellins. Further, the isolates have assayed for the ability to promote the growth of mutant rice Waito-C. The plants associated with TS1 and BRL1 have shown higher chlorophyll content, root-shoot length, and biomass production. The growth promoting activity of the endophytes can be attributed to the various types of GAs and IAA that have been observed in the culture filtrates of the endophytes by the Gas chromatography/mass spectrometry (GC/MS). The GC/MS analysis revealed the presence of different gibberellins concentrations (ng/ml) in TS1 and BRL1 culture filtrate, i.e. GA1 (0.091?±?0.009, 0.392?±?0.007), GA3 (0.324?±?0.077, 0.089?±?0.0007) and GA7 (0.023?±?0.002, 0.492?±?0.005), respectively. Besides, a significant up regulation of plant endogenous GA1 (12.443?±?0.454 and 15.434?±?0.245) has been obsereved in TS1 and BRL1 associated plants compared to the control. Moreover, semi quantitative RT-PCR has confirmed the presence/invovment of GA pathways genes (P50–1, P450–3, P450–4, ggs2, and des). The results conclude that the endophytes isolated in this study can ably synthesize bioactive compounds, which play an important role in plant growth promotion. 相似文献
92.
Bilge Hilal Cadirci Ihsan Yasa Ali Kocyigit 《Preparative biochemistry & biotechnology》2016,46(1):23-29
Solid-state fermentation (SSF) is a bioprocess that doesn’t need an excess of free water, and it offers potential benefits for microbial cultivation for bioprocesses and product development. In comparing the antibiotic production, few detailed reports could be found with lipolytic enzyme production by Streptomycetes in SSF. Taking this knowledge into consideration, we prefer to purify Actinomycetes species as a new source for lipase production. The lipase-producing strain Streptomyces sp. TEM 33 was isolated from soil and lipase production was managed by solid-state fermentation (SSF) in comparison with submerged fermentation (SmF). Bioprocess-affecting factors like initial moisture content, incubation time, and various carbon and nitrogen additives and the other enzymes secreted into the media were optimized. Lipase activity was measured as 1.74 ± 0.0005 U/g dry substrate (gds) by the p-nitrophenylpalmitate (pNPP) method on day 6 of fermentation with 71.43% final substrate moisture content. In order to understand the metabolic priority in SSF, cellulase and xylanase activity of Streptomyces sp. TEM33 was also measured. The microorganism degrades the wheat bran to its usable form by excreting cellulases and xylanases; then it secretes the lipase that is necessary for degrading the oil in the medium. 相似文献
93.
Ihsan ul Haq ;Marc J. B. Vreysen ;P. E. A. Teal ;Jorge Hendrichs 《Entomologia Sinica》2014,(5):637-646
Methoprene (an analogue of juvenile hormone) application and feeding on a protein diet is known to enhance male melon fly, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), mating success. In this study, we investigated the effect of these treatments on male B. cucurbitae's ability to inhibit female remating. While 14-d-old females were fed on protein diet, 6-d-old males were exposed to one of the following treatments: (i) topical application of methoprene and fed on a protein diet; (ii) no methoprene but fed on a protein diet; (iii) methoprene and sugar-fed only; and (iv) sugar-fed, 14-d-old males acted as controls. Treatments had no effect on a male's ability to depress the female remating receptivity in comparison to the control. Females mated with protein-deprived males showed higher remating receptivity than females first mated with protein-fed males. Methoprene and protein diet interaction had a positive effect on male mating success during the first and second mating of females. Significantly more females first mated with sugar-fed males remated with protein-fed males and females first mated with methoprene treated and protein-fed males were more likely to remate with similarly treated males. Females mating latency (time to start mating) was significantly shorter with protein-fed males, and mating duration was significantly longer with protein-fed males compared with protein-deprived males. These results are discussed in the context of methoprene and/or dietary protein as prerelease treatment of sterile males in area-wide control of melon fly integrating the sterile insect technique (SIT). 相似文献
94.
Abdul Latif Khan Muhammad Waqas Sang-Mo Kang Ahmed Al-Harrasi Javid Hussain Ahmed Al-Rawahi Salima Al-Khiziri Ihsan Ullah Liaqat Ali Hee-Young Jung In-Jung Lee 《Journal of microbiology (Seoul, Korea)》2014,52(8):689-695
Plant growth promoting endophytic bacteria have been identified as potential growth regulators of crops. Endophytic bacterium, Sphingomonas sp. LK11, was isolated from the leaves of Tephrosia apollinea. The pure culture of Sphingomonas sp. LK11 was subjected to advance chromatographic and spectroscopic techniques to extract and isolate gibberellins (GAs). Deuterated standards of [17, 17-2H2]-GA4, [17, 17-2H2]-GA9 and [17, 17-2H2]-GA20 were used to quantify the bacterial GAs. The analysis of the culture broth of Sphingomonas sp. LK11 revealed the existence of physiologically active gibberellins (GA4: 2.97 ± 0.11 ng/ml) and inactive GA9 (0.98 ± 0.15 ng/ml) and GA20 (2.41 ± 0.23). The endophyte also produced indole acetic acid (11.23 ± 0.93 μM/ml). Tomato plants inoculated with endophytic Sphingomonas sp. LK11 showed significantly increased growth attributes (shoot length, chlorophyll contents, shoot, and root dry weights) compared to the control. This indicated that such phyto-hormones-producing strains could help in increasing crop growth. 相似文献
95.
Scabies and pediculosis are ubiquitous, contagious, and debilitating parasitic dermatoses. The tendency of high prevalence of pediculosis and scabies among school and preschool age children has prompted us to conduct a head louse and scabies prevalence survey among preschool nursery children in our district. A school-based, crosssectional study was performed, with 1,134 children chosen for evaluation. All cases were evaluated by physical examination and a detailed, structured questionnaire. The infestation was found in 14 (1.2%) of 1,134 children; 9 (0.8%) with pediculosis capitis and 5 (0.4%) with scabies. We found that infestations were more frequent in children with mothers whose education levels were low. This indicates the necessity of an improvement in the economic and sociocultural status of the community and the promotion of hygiene concepts and practices in order to improve health of preschool age children. 相似文献
96.
Baibutoside (5), a new cycloartane-type triterpene glycoside, has been isolated from the roots of Astragalus baibutensis along with four known glycosides, acetylastragaloside I (1), and astragalosides I, II, and IV (2-4, resp.). The structure elucidation of the compounds were achieved by a combination of one- and two-dimensional NMR techniques (DQF-COSY, HSQC, HMBC, and ROESY), and mass spectrometry (ESI-MS), where all the compounds were shown to have cycloastragenol (=(20R,24S)-3beta,6alpha,16beta,25-tetrahydroxy-20,24-epoxy-9,19-cyclolanostane) as aglycone. All compounds were tested for in vitro antiprotozoal activity. Compounds 1-4 displayed notable activity vs. Trypanosoma brucei rhodesiense, with acetylastragaloside I (1) being the most potent (IC50 9.5 microg/ml). Acetylastragaloside I (1) was also lethal to T. cruzi (IC50 5.0 microg/ml), and it is the first cycloartane-type triterpene with remarkable trypanocidal activity against both T. brucei rhodesiense and T. cruzi. However, it exhibits some cytotoxicity on mammalian cells. 相似文献
97.
A new amperometric whole cell biosensor based on Saccharomyces cerevisiae immobilized in gelatin was developed for selective determination of vitamin B1 (thiamine). The biosensor was constructed by using gelatin and crosslinking agent glutaraldehyde to immobilize S. cerevisiae cells on the Teflon membrane of dissolved oxygen (DO) probe used as the basic electrode system combined with a digital oxygen meter. The cells were induced by vitamin B1 in the culture medium, and the cells used it as a carbon source in the absence of glucose. So, when the vitamin B1 solution is injected into the whole cell biosensor system, an increase in respiration activity of the cells results from the metabolic activity and causes a decrease in the DO concentration of interval surface of DO probe related to vitamin B1 concentration. The response time of the biosensor is 3 min, and the optimal working conditions of the biosensor were carried out as pH 7.0, 50mM Tris-HCl, and 30 degrees C. A linear relationship was obtained between the DO concentration decrease and vitamin B1 concentration between 5.0 x 10(-3) and 10(-1) microM. In the application studies of the biosensor, sensitive determination of vitamin B1 in the vitamin tablets was investigated. 相似文献
98.
Beck JB Alexander PJ Allphin L Al-Shehbaz IA Rushworth C Bailey CD Windham MD 《Evolution; international journal of organic evolution》2012,66(4):985-995
Gametophytic apomixis is a common form of asexual reproduction in plants. Virtually all gametophytic apomicts are polyploids, and some view polyploidy as a prerequisite for the transition to apomixis. However, any causal link between apomixis and polyploidy is complicated by the fact that most apomictic polyploids are allopolyploids, leading some to speculate that hybridization, rather than polyploidy, enables apomixis. Diploid apomixis presents a rare opportunity to isolate the role of hybridization, and a number of diploid apomicts have been documented in the genus Boechera (Brassicaceae). Here, we present the results of a microsatellite study of 1393 morphologically and geographically diverse diploid individuals, evaluating the hypothesis that diploid Boechera apomicts are hybrids. This genus‐wide dataset was made possible by the applicability of a core set of microsatellite loci in 69 of the 70 diploid Boechera species and by our ability to successfully genotype herbarium specimens of widely varying ages. With few exceptions, diploid apomicts exhibited markedly high levels of heterozygosity resulting from the combination of disparate genomes. This strongly suggests that most apomictic diploid Boechera lineages are of hybrid origin, and that the genomic consequences of hybridization allow for the transition to gametophytic apomixis in this genus. 相似文献
99.
Mike Gerards Bianca van den Bosch Chantal Calis Kees Schoonderwoerd Klaartje van Engelen Marina Tijssen René de Coo Anneke van der Kooi Hubert Smeets 《Mitochondrion》2010,10(5):510-515
Hereditary ataxias are genetic disorders characterized by uncoordinated gait and often poor coordination of hands, speech, and eye movements. Frequently, atrophy of the cerebellum occurs. Many ataxias are autosomal dominant, but autosomal recessive (AR) disease occurs as well. Homozygosity mapping in a consanguineous family with three affected children with progressive cerebellar ataxia and atrophy revealed a candidate locus on chromosome 1, containing the CABC1/ADCK3 (the chaperone, ABC1 activity of bc1 complex homologue) gene. CABC1/ADCK3 is the homologue of the yeast Coq8 gene, which is involved in the ubiquinone biosynthesis pathway. Mutation analysis of this gene showed a homozygous nonsense mutation (c.1042C > T, p.R348X). Eight additional patients with AR cerebellar ataxia and atrophy were screened for mutations in the CABC1/ADCK3 gene. One patient was compound heterozygous for the same c.1042C > T mutation and a second nonsense mutation (c.1136T > A, p.L379X). Both mutations created a premature stop codon, triggering nonsense mediated mRNA decay as the pathogenic mechanism. We found no evidence of a Dutch founder for the c.1042C > T mutation in AR ataxia. We report here the first nonsense mutations in CABC1 that most likely lead to complete absence of a functional CABC1 protein. Our results indicate that CABC1 is an important candidate for mutation analysis in progressive cerebellar ataxia and atrophy on MRI to identify those patients, who may benefit from CoQ10 treatment. 相似文献
100.
Leslie A Khawli Sirj Goswami Ryan Hutchinson Zephania W Kwong Jihong Yang Xiangdan Wang Zhenling Yao Alavattam Sreedhara Tony Cano Devin Tesar Ihsan Nijem David E Allison Pin Yee Wong Yung-Hsiang Kao Cynthia Quan Amita Joshi Reed J Harris Paul Motchnik 《MABS-AUSTIN》2010,2(6):613-624
Antibody charge variants have gained considerable attention in the biotechnology industry due to their potential influence on stability and biological activity. Subtle differences in the relative proportions of charge variants are often observed during routine biomanufacture or process changes and pose a challenge to demonstrating product comparability. To gain further insights into the impact on biological activity and pharmacokinetics (PK) of monoclonal antibody (mAb) charge heterogeneity, we isolated the major charge forms of a recombinant humanized IgG1 and compared their in vitro properties and in vivo PK. The mAb starting material had a pI range of 8.7–9.1 and was composed of about 20% acidic variants, 12% basic variants and 68% main peak. Cation exchange displacement chromatography was used to isolate the acidic, basic and main peak fractions for animal studies. Detailed analyses were performed on the isolated fractions to identify specific chemical modification contributing to the charge differences and were also characterized for purity and in vitro potency prior to being administered either subcutaneously (SC) or intravenously (IV) in rats. All isolated materials had similar potency and rat FcRn binding relative to the starting material. Following IV or SC administration (10 mg/kg) in rats, no difference in serum PK was observed, indicating that physiochemical modifications and pI differences among charge variants were not sufficient to result in PK changes. Thus, these results provided meaningful information for the comparative evaluation of charge-related heterogeneity of mAbs and suggested that charge variants of IgGs do not affect the in vitro potency, FcRn binding affinity or the PK properties in rats.Key words: mAb IgG1, charge heterogeneity, isoelectric point, neonatal Fc receptor (FcRn), pharmacokinetics, potency 相似文献