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21.
Hagiwara Y Kawamura YI Kataoka K Rahima B Jackson RJ Komase K Dohi T Boyaka PN Takeda Y Kiyono H McGhee JR Fujihashi K 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(5):3045-3054
Nasal application of native cholera toxin (nCT) as a mucosal adjuvant has potential toxicity for the CNS through binding to GM1 gangliosides in the olfactory nerves. Although mutants of cholera toxin (mCTs) have been developed that show mucosal adjuvant activity without toxicity, it still remains unclear whether these mCTs will induce CNS damage. To help overcome these concerns, in this study we created new double mutant CTs (dmCTs) that have two amino acid substitutions in the ADP-ribosyltransferase active center (E112K) and COOH-terminal KDEL (E112K/KDEV or E112K/KDGL). Confocal microscopic analysis showed that intracellular localization of dmCTs differed from that of mCTs and nCTs in intestinal epithelial T84 cells. Furthermore, both dmCTs exhibited very low toxicity in the Y1 cell assay and mouse ileal loop tests. When mucosal adjuvanticity was examined, both dmCTs induced enhanced OVA-specific immune responses in both mucosal and systemic lymphoid tissues. Interestingly, although both dmCT E112K/KDEV and dmCT E112K/KDGL showed high Th2-type and significant Th1-type cytokine responses by OVA-specific CD4+ T cells, dmCT E112K/KDEV exhibited significantly lower Th1-type cytokine responses than did nCT and dmCT E112K/KDGL. These results show that newly developed dmCTs retain strong biological adjuvant activity without CNS toxicity. 相似文献
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23.
Prevention of flap necrosis by chlorpromazine 总被引:1,自引:0,他引:1
Chlorpromazine administered to Sprague-Dawley rats 30 minutes prior to elevation of McFarlane back flaps and continued 14 days thereafter resulted in near complete flap survival, compared with 48 percent necrosis in control animals. Chlorpromazine demonstrates a wide variety of actions that appear to meet all presently known requirements for flap preservation. 相似文献
24.
Almas Fakhrah Hassan Adeel Bibi Arfa Ali Masab Lateef Sadia Mahmood Tariq Rasheed Awais Quraishi Umar Masood 《Plant and Soil》2018,431(1-2):371-387
Plant and Soil - Extreme climate events, including flooding and prolonged drought, may establish long-lasting (legacy) effects on soil abiotic and biotic properties, potentially influencing soil... 相似文献
25.
Muhammad Idrees Bibi Sania Bibi Hafsa Sana Kumari Haji Khan Hina Fazal Ishfaq Ahmad Fazal Akbar Naveed Ahmad Sadeeq Ali Nisar Ahmad 《Comptes rendus biologies》2018,341(6):334-342
Stevia rebaudiana (S. rebaudiana) is the most important therapeutic plant species and has been accepted as such worldwide. It has a tendency to accumulate steviol glycosides, which are 300 times sweeter than marketable sugar. Recently, diabetic patients commonly use this plant as a sugar substitute for sweet taste. In the present study, the effects of different spectral lights were investigated on biomass accumulation and production of secondary metabolites in adventitious root cultures of S. rebaudiana. For callus development, leaf explants were excised from seed-derived plantlets and inoculated on a Murashige and Skoog (MS) medium containing the combination of 2,4-dichlorophenoxy acetic acid (2, 4-D, 2.0 mg/l) and 6-benzyladenine (BA, 2.0 mg/l), while 0.5 mg/l naphthalene acetic acid (NAA) was used for adventitious root culture. Adventitious root cultures were exposed to different spectral lights (blue, green, violet, red and yellow) for a 30-day period. White light was used as control. The growth kinetics was studied for 30 days with 3-day intervals. In this study, the violet light showed the maximum accumulation of fresh biomass (2.495 g/flask) as compared to control (1.63 g/flask), while red light showed growth inhibition (1.025 g/flask) as compared to control. The blue light enhanced the highest accumulation of phenolic content (TPC; 6.56 mg GAE/g DW), total phenolic production (TPP; 101 mg/flask) as compared to control (5.44 mg GAE/g DW; 82.2 mg GAE/g DW), and exhibited a strong correlation with dry biomass. Blue light also improved the accumulation of total flavonoid content (TFC; 4.33 mg RE/g DW) and total flavonoid production (TFP; 65 mg/flask) as compared to control. The violet light showed the highest DPPH inhibition (79.72%), while the lowest antioxidant activity was observed for control roots (73.81%). Hence, we concluded that the application of spectral lights is an auspicious strategy for the enhancement of the required antioxidant secondary metabolites in adventitious root cultures of S. rebaudiana and of other medicinal plants. 相似文献
26.
Vered Elgazar Vladimir Razanov Meredin Stoltenberg Michal Hershfinkel Mahmoud Huleihel Yuval Bibi Nitzan Eitan Lunenfeld Israel Sekler William F Silverman 《The journal of histochemistry and cytochemistry》2005,53(7):905-912
Zinc ions play an important role in testis development and spermatogenesis. Thus, nutritional zinc deficiency leads to aberrant testicular development, reduced spermatogenesis, and male sterility. The precise actions of zinc in mediating these functions and the mechanisms by which zinc is itself regulated in the testis, however, have not been adequately elucidated. We have assessed the distribution of the zinc-regulating proteins ZnT-1 and metallothionein I/II (MT I/II) in the mouse seminiferous tubule. Co-labeling for ZnT-1 and MT I/II demonstrated unique patterns of distribution for these proteins, with ZnT-1 present in Sertoli cells in addition to luminal spermatozoa and MT I/II restricted to spermatocytes. These findings were confirmed by dual-label immunofluorescence for ZnT-1 and the Sertoli cell marker, vimentin, and by immunoelectron microscopy. The differential expression patterns of ZnT-1 and MTs support the hypothesis that ZnT-1 and MTs play different roles in the regulation of intracellular zinc in this organ. The specific expression of ZnT-1 in the Sertoli cells, moreover, is consistent with their role in maintaining a nurturing, closely regulated environment for spermatogenesis. 相似文献
27.
MdfA is a 410-residue-long secondary multidrug transporter from E. coli. Cells expressing MdfA from a multicopy plasmid exhibit resistance against a diverse group of toxic compounds, including neutral and cationic ones, because of active multidrug export. As a prerequisite for high-resolution structural studies and a better understanding of the mechanism of substrate recognition and translocation by MdfA, we investigated its biochemical properties and overall structural characteristics. To this end, we purified the beta-dodecyl maltopyranoside (DDM)-solubilized protein using a 6-His tag and metal affinity chromatography, and size exclusion chromatography (SE-HPLC). Purified MdfA was analyzed for its DDM and phospholipid (PL) content, and tetraphenylphosphonium (TPP+)-binding activity. The results are consistent with MdfA being an active monomer in DDM solution. Furthermore, an investigation of two-dimensional crystals by electron crystallography and 3D reconstruction lent support to the notion that MdfA may also be monomeric in reconstituted proteoliposomes. 相似文献
28.
Farhana Bibi Humaira Yasmin Asif Jamal Mohammad S. AL-Harbi Mushtaq Ahmad Muhammad Zafar Bashir Ahmad Bassem N. Samra Atef F. Ahmed Muhammad Ishtiaq Ali 《Saudi Journal of Biological Sciences》2021,28(12):7595
Microalgae biomass is considered an important feedstock for biofuels and other bioactive compounds due to its faster growth rate, high biomass production and high biomolecules accumulation over first and second-generation feedstock. This research aimed to maximize the specific growth rate of fresh water green microalgae Closteriopsis acicularis, a member of family Chlorellaceae under the effect of pH and phosphate concentration to attain enhanced biomass productivity. This study investigates the individual and cumulative effect of phosphate concentration and pH on specific growth characteristics of Closteriopsis acicularis in autotrophic mode of cultivation for bioethanol production. Central-Composite Design (CCD) strategy and Response Surface Methodology (RSM) was used for the optimization of microalga growth and ethanol production under laboratory conditions. The results showed that high specific growth rate and biomass productivity of 0.342 day−1 and 0.497 g L−1 day−1 respectively, were achieved at high concentration of phosphate (0.115 g L−1) and pH (9) at 21st day of cultivation. The elemental composition of optimized biomass has shown enhanced elemental accumulation of certain macro (C, O, P) and micronutrients (Na, Mg, Al, K, Ca and Fe) except for nitrogen and sulfur. The Fourier transform infrared spectroscopic analysis has revealed spectral peaks and high absorbance in spectral range of carbohydrates, lipids and proteins, in optimized biomass. The carbohydrates content of optimized biomass was observed as 58%, with 29.3 g L−1 of fermentable sugars after acid catalyzed saccharification. The bioethanol yield was estimated as 51 % g ethanol/g glucose with maximum of 14.9 g/L of bioethanol production. In conclusion, it can be inferred that high specific growth rate and biomass productivity can be achieved by varying levels of phosphate concentration and pH during cultivation of Closteriopsis acicularis for improved yield of microbial growth, biomass and bioethanol production. 相似文献
29.
Yousafi Qudsia Amin Humaira Bibi Shabana Rafi Rafea Khan Muhammad S. Ali Hamza Masroor Ashir 《International journal of peptide research and therapeutics》2021,27(4):2685-2701
International Journal of Peptide Research and Therapeutics - Klebsiella oxytoca is a gram-negative bacterium. It is opportunistic in nature and causes hospital acquired infections.... 相似文献
30.
David Bibi Hafiz Mawasi Alessio Nocentini Claudiu T. Supuran Bogdan Wlodarczyk Richard H. Finnell Meir Bialer 《Neurochemical research》2017,42(7):1972-1982
Epilepsy is one of the most common neurological diseases, with between 34 and 76 per 100,000 people developing epilepsy annually. Epilepsy therapy for the past 100+ years is based on the use of antiepileptic drugs (AEDs). Despite the availability of more than twenty old and new AEDs, approximately 30% of patients with epilepsy are not seizure-free with the existing medications. In addition, the clinical use of the existing AEDs is restricted by their side-effects, including the teratogenicity associated with valproic acid that restricts its use in women of child-bearing age. Thus, there is an unmet clinical need to develop new, effective AEDs. In the present study, a novel class of carbamates incorporating phenethyl or branched aliphatic chains with 6–9 carbons in their side-chain, and 4-benzenesulfonamide-carbamate moieties were synthesized and evaluated for their anticonvulsant activity, teratogenicity and carbonic anhydrase (CA) inhibition. Three of the ten newly synthesized carbamates showed anticonvulsant activity in the maximal-electroshock (MES) and 6 Hz tests in rodents. In mice, 3-methyl-2-propylpentyl(4-sulfamoylphenyl)carbamate(1), 3-methyl-pentan-2-yl-(4-sulfamoylphenyl)carbamate (9) and 3-methylpentyl, (4-sulfamoylphenyl)carbamate (10) had ED50 values of 136, 31 and 14 mg/kg (MES) and 74, 53, and 80 mg/kg (6 Hz), respectively. Compound (10) had rat-MES-ED50?=?13 mg/kg and ED50 of 59 mg/kg at the mouse-corneal-kindling test. These potent carbamates (1,9,10) induced neural tube defects only at doses markedly exceeding their anticonvuslnat-ED50 values. None of these compounds were potent inhibitors of CA IV, but inhibited CA isoforms I, II and VII. The anticonvulsant properties of these compounds and particularly compound 10 make them potential candidates for further evaluation and development as new AEDs. 相似文献