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31.
Vascular endothelial growth factor (VEGF) is the important angiogenic factor associated with tumor growth and metastasis in a wide variety of solid tumors. The aim of this study is to investigate the tumor suppressive effect of chitosan/small interfering RNA (siRNA)-VEGF nanoplexes in the rat breast cancer model. Chitosan/siRNA nanoplexes (siVEGF-A, siVEGFR-1, siVEGFR-2) and NRP-1 were prepared in a 15 to1 ratio and injected (intratumorally) into the breast-tumor-bearing Sprague-Dawley rats. Tumor volumes were measured during 21 days. To investigate the effect of chitosan/siRNA nanoplexes on VEGF expression in tumors, VEGF was analyzed with immunohistochemistry and western blotting. The mRNA levels of VEGF in tumor samples were determined with real-time PCR (RT-PCR). After siRNA treatment, a marked reduction in tumor volumes was measured in complex-injected rats (97%). Free siRNA injection showed lower tumor inhibition. Reduction of VEGF protein was also shown with western blotting and immunohistochemistry. Similar results were obtained with RT-PCR also. These results indicate that the chitosan/siRNA targeting to VEGF nanoplexes have a remarkably suppressive effect on VEGF expression and tumor volume in breast cancer model of rats.  相似文献   
32.
Reversal of neuromuscular blockage induced by steroidal neuromuscular blocking agents such as rocuronium can be achieved using normal dose of sugammadex, which has been shown to be very effective for such reversal. In this study, we determined the effects of sugammadex on calcineurin immunoreactivity by examining the histopathological and histochemical structure of rat testis cells after neuromuscular blockage. Moreover, the regional distribution levels of calcineurin immunopositive testes cells were investigated. Eighteen adult male, Sprague–Dawley rats were divided into one control and two study groups. Study groups 1 and 2 rats received sugammadex at doses of 16 and 96 mg kg−1 i.v., respectively, after rocuronium treatment (mg kg−1 i.v.). The control group received intravenous 0.9% NaCl 1 ml. i.v without any drug. Our study demonstrates that sugammadex is safe and effective for reversal of rocuronium effects in rats, as well as in other animals and humans. Furthermore, histopathological examination indicates that high levels of sugammadex–rocuronium complexes accumulate a little in testis tissue. We found that rocuronium-sugammadex complexes were remained in circulation for a long time resulting in a decrease in interstitial space, testis size, germ cell numbers and Leydig cell numbers. Calcineurin immunoreactivity was higher in the experimental groups than the control group due to increase of calcium level. The results suggest that sugammadex–rocuronium complexes are cause histopathological and immunohistochemical changes in testis interstitial tissues, as well as changes in sperm density and germ cell number.  相似文献   
33.
Silicon improves salinity tolerance in wheat plants   总被引:5,自引:0,他引:5  
Durum wheat (Triticum durum cv. Gediz-75) and bread wheat (Triticum aestivum cv. Izmir-85) were grown in a complete nutrient solution in a growth room to investigate effect of silicone supplied to the nutrient solution on plants grown at salt stress. The experiment was a 2 × 2 factorial arrangement with two levels of NaCl in nutrient solution, 0 and 100 mM, and two levels of silicone (Si) in nutrient solution, 0.25 and 0.50 mM, as Na2SiO3. The plants grown at 100 mM NaCl produced less dry matter and chlorophyll content than those without NaCl. Supplementary Si at both 0.25 and 0.5 mM ameliorated the negative effects of salinity on plant dry matter and chlorophyll content. Membrane permeability and proline content in leaves increased with addition of 100 mM NaCl and these increases were decreased with Si treatments. Sodium (Na) concentration in plant tissues increased in both leaves and roots of plants in the high NaCl treatment and Si treatments lowered significantly the concentrations of Na in both leaves and roots. Bread wheat was more tolerant to salinity than durum wheat. The accumulation of Na in roots indicates a possible mechanism whereby bread wheat copes with salinity in the rooting medium and/or may indicate the existence of an inhibition mechanism of Na transport to leaves. Concentrations of both Ca and K were lower in the plants grown at high NaCl than in those in the control treatment and these two element concentrations were increased by Si treatments in both shoots and roots but remained lower than control values in most cases.  相似文献   
34.
35.
Kesterite is an attractive material for absorber layers in thin film photovoltaics. Solar cells based on kesterite have shown a substantial progress over the last decade; nevertheless, further improvements in device efficiency are pending due to the open‐circuit voltage (Voc) deficit (i.e., difference between the maximum V oc that can be achieved according to Shockley–Queisser limit and actual V oc from the device). In this study, the optoelectronic properties of the author's internal record Cu2ZnSnSe4 solar cell, which shows a power conversion efficiency of 11.4%, are presented. The device measurements reveal a Voc deficit of 337 mV, which is one of the lowest V oc deficits in the literature. Moreover, an unusual behavior for kesterite is observed: (i) photon energy of the photoluminescence emission and (ii) the extrapolated V oc for 0 K are both matching the band gap region of the absorber. These results indicate a significant improvement in the recombination characteristics and absorber quality in comparison to other kesterite devices in literature.  相似文献   
36.
This study was performed to investigate the serum and hair zinc levels in patients having epilepsy diagnoses who were intended to be put on valproic acid (VA) monotherapy and had never ingested antiepileptics before. A total of 16 patients having normal growth, development, and nutrition was selected as Group 1, and Group 2 was made up of 10 patients who had received VA monotherapy for 2 yrs or more and had normal growth, development, and nutrition characteristics. A control group (Group 3) was formed of 15 subjects who applied to the hospital for upper respiratory tract disorders. Serum and hair samples were taken for zinc assays from the Group 1 patients on the d 0, 15, 30, 45, 60, 75, and 180. Groups 2 and 3 were sampled only once, and zinc levels were determined. We found that both serum and hair zinc levels in Group 1 were higher than those of Group 2 and control group before the beginning of VA therapy, but they returned to normal during VA treatment. There was no zinc deficiency, and zinc replacement treatment may therefore be considered as unnecessary.  相似文献   
37.
Last larval instars and pupae of Mononychus punctumalbum (Herbst, 1784) and Mononychus schoenherri Kolenati, 1859 (Curculionidae, Ceutorhynchinae) are described in detail for the first time. No immatures of other species of this genus had previously been described. The immatures of Mononychus were compared with available data on immatures of all genera in the subfamily Ceutorhynchinae. Both the larvae and pupae of the two Mononychus species are very distinctive, having distinct characters from other genera in the subfamily Ceutorhynchinae. New bionomic data for M. punctumalbum concerning its host preferences for Iris species in central Europe can be used to verify literature data indicating the important role of the iris weevil in the dramatic decline in the plant's abundance in natural habitats as well as in gardens and other anthropogenic associations.  相似文献   
38.
Micronutrient malnutrition, and particularly deficiency in zinc (Zn) and iron (Fe), afflicts over three billion people worldwide, and nearly half of the world’s cereal-growing area is affected by soil Zn deficiency. Wild emmer wheat [Triticum turgidum ssp. dicoccoides (Körn.) Thell.], the progenitor of domesticated durum wheat and bread wheat, offers a valuable source of economically important genetic diversity including grain mineral concentrations. Twenty two wild emmer wheat accessions, representing a wide range of drought resistance capacity, as well as two durum wheat cultivars were examined under two contrasting irrigation regimes (well-watered control and water-limited), for grain yield, total biomass production and grain Zn, Fe and protein concentrations. The wild emmer accessions exhibited high genetic diversity for yield and grain Zn, Fe and protein concentrations under both irrigation regimes, with a considerable potential for improvement of the cultivated wheat. Grain Zn, Fe and protein concentrations were positively correlated with one another. Although irrigation regime significantly affected ranking of genotypes, a few wild emmer accessions were identified for their advantage over durum wheat, having consistently higher grain Zn (e.g., 125 mg kg?1), Fe (85 mg kg?1) and protein (250 g kg?1) concentrations and high yield capacity. Plants grown from seeds originated from both irrigation regimes were also examined for Zn efficiency (Zn deficiency tolerance) on a Zn-deficient calcareous soil. Zinc efficiency, expressed as the ratio of shoot dry matter production under Zn deficiency to Zn fertilization, showed large genetic variation among the genotypes tested. The source of seeds from maternal plants grown under both irrigation regimes had very little effect on Zn efficiency. Several wild emmer accessions revealed combination of high Zn efficiency and drought stress resistance. The results indicate high genetic potential of wild emmer wheat to improve grain Zn, Fe and protein concentrations, Zn deficiency tolerance and drought resistance in cultivated wheat.  相似文献   
39.
Mineral nutrient malnutrition, and particularly deficiency in zinc and iron, afflicts over 3 billion people worldwide. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, genepool harbors a rich allelic repertoire for mineral nutrients in the grain. The genetic and physiological basis of grain protein, micronutrients (zinc, iron, copper and manganese) and macronutrients (calcium, magnesium, potassium, phosphorus and sulfur) concentration was studied in tetraploid wheat population of 152 recombinant inbred lines (RILs), derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16). Wide genetic variation was found among the RILs for all grain minerals, with considerable transgressive effect. A total of 82 QTLs were mapped for 10 minerals with LOD score range of 3.2–16.7. Most QTLs were in favor of the wild allele (50 QTLs). Fourteen pairs of QTLs for the same trait were mapped to seemingly homoeologous positions, reflecting synteny between the A and B genomes. Significant positive correlation was found between grain protein concentration (GPC), Zn, Fe and Cu, which was supported by significant overlap between the respective QTLs, suggesting common physiological and/or genetic factors controlling the concentrations of these mineral nutrients. Few genomic regions (chromosomes 2A, 5A, 6B and 7A) were found to harbor clusters of QTLs for GPC and other nutrients. These identified QTLs may facilitate the use of wild alleles for improving grain nutritional quality of elite wheat cultivars, especially in terms of protein, Zn and Fe.  相似文献   
40.
In the present study, a new series of 2-[4-(pyrimidin-2-yl)piperazin-1-yl]-2-oxoethyl 4-substituted piperazine-1-carbodithioate derivatives (2a-n) were synthesized and screened for their monoamine oxidase A and B inhibitory activity. The structures of compounds were elucidated using spectroscopic methods and some physicochemical properties of new compounds were predicted using Molinspiration and MolSoft programs. Compounds 2-[4-(pyrimidin-2-yl)piperazin-1-yl]-2-oxoethyl 4-(4-nitrophenyl)piperazine-1-carbodithioate (2j) and 2-[4-(pyrimidin-2-yl)piperazin-1-yl]-2-oxoethyl 4-benzhydrylpiperazine-1-carbodithioate (2m) exhibited selective MAO-A inhibitory activity with IC50?=?23.10, 24.14?µM, respectively. Some of the biological results were found in accordance with the obtained in silico data based on Lipinski’s fule of five.  相似文献   
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