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11.
Baig MR  Rajan G  Yunus N 《Gerodontology》2012,29(2):e1140-e1145
Dental rehabilitation of a completely edentulous geriatric patient has always been a challenge to the clinician, especially in treating those with higher expectations and demands. Treatment duration and the amount of residual alveolar bone available are often important considerations when planning for dental implant-based fixed treatment for these patients. With the introduction of zygomatic implants, a graftless alternative solution has emerged for deficient maxillary bone with provision for immediate loading. This article describes the treatment of a completely edentulous elderly patient using zygomatic implants in conjunction with conventional implants. The implants were immediately loaded using a definitive acrylic resin fixed denture reinforced with a cast metal framework, to provide function and aesthetics.  相似文献   
12.
Plants used as natural dye sources in Turkey   总被引:1,自引:0,他引:1  
This study was carried out in the regions where handcrafts such as carpet and rug weaving are common in Turkey. In the regions where natural dyes are used, 123 plant species belonging to 50 families were identified as sources of natural dyes. In natural dye production, different parts of the plant or the whole aboveground plant is used. Ten different colors are gained from the plants. Sometimes the same color can be obtained from different plants. By mixing different plants, it is possible to produce various colors. We also identified more than 12 natural and more than eight chemical assistant substances (mordant) that are used in the regions to bind dye to fibers, to maintain the strongness and brightness of the colors, and to obtain various colors  相似文献   
13.
BackgroundNanotechnology application has successfully reached numerous scientific breakthroughs including in radiotherapy. However, the clinical application of nanoparticles requires more diligent research primarily on the crucial parameters such as nanoparticle sizes. This study is aimed to investigate the influence of bismuth oxide nanorod (Bi2O3-NR) sizes on radiosensitization effects on MCF-7 and HeLa cell lines for megavoltage photon and electron beam radiotherapy.Materials and methodsMCF-7 and HeLa cells were treated with and without 0.5 μMol/L of Bi2O3-NR of varying sizes (60, 70, 80, and 90 nm). The samples, including the control groups, were exposed to different radiation doses (0–10 Gy), using photon (6 MV and 10 MV), and electron beam (6 MeV and 12 MeV) radiotherapy. Clonogenic assay was performed, and sensitization enhancement ratio (SER) was determined from linear quadratic based cell survival curves.ResultsThe results depicted that 60 nm Bi2O3-NR yields the most excellent SER followed by 70 nm Bi2O3-NR. Meanwhile, the 80 and 90 nm Bi2O3-NR showed an insignificant difference between treated and untreated cell groups. This study also found that MCF-7 was subjected to more cell death compared to HeLa.Conclusion60 nm Bi2O3-NR was the optimal Bi2O3-NR size to induce radiosensitization effects for megavoltage external beam radiotherapy. The SER in photon beam radiotherapy marked the highest compared to electron beam radiotherapy due to decreased primary radiation energy from multiple radiation interaction and higher Compton scattering.  相似文献   
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15.
水分胁迫对大果沙枣光合特性及生物量分配的影响   总被引:16,自引:0,他引:16  
选取大果沙枣1年生幼苗,盆栽于相对含水量分别为70%~75%(CK)、50%~55%(T1)、35%~40%(T2)和15%~20%(T3)的土壤中培养25 d,研究大果沙枣在水分胁迫下的光合特性变化和生物产量积累及其分配规律。结果显示:水分胁迫抑制了大果沙枣的光合作用,与对照相比,T2和T3处理导致净光合速率、叶片蒸腾速率和水分利用效率显著降低,气孔阻力、胞间二氧化碳浓度和叶绿素含量升高,而且光合午休明显,非气孔因素是干旱时大果沙枣净光合速率下降的主要原因;水分胁迫下,大果沙枣的生长受到抑制,地上部分和地下部分的干生物量积累同时降低,但地下干生物量降低的程度低于地上部分;干旱处理中,T3处理显著抑制大果沙枣的生长,但仍保持一定的生物量增加。结果表明:大果沙枣具有一定的自我调节与保护能力,在水分胁迫下大果沙枣趋于将更多的资源分配给根系,以提高根冠比而适应干旱的环境。  相似文献   
16.

Background

Human infections with non-O1, non-O139 V. cholerae have been described from Laos. Elsewhere, non cholera-toxin producing, non-O1, non-O139 V. cholerae have been described from blood cultures and ascitic fluid, although they are exceedingly rare isolates.

Case presentation

We describe a farmer who died with Vibrio cholerae O21 bacteremia and peritonitis in Vientiane, Laos, after eating partially cooked apple snails (Pomacea canaliculata) and mussels (Ligumia species). The cultured V. cholerae were non-motile. PCR detected ompW and toxR gene regions but not the ctxA, ompU, omp K and TCP gene regions. Although the organisms lacked flagellae on scanning electron microscopy, they possessed the Vibrio flagellin flaA gene.

Conclusion

Severe bacteremic non-O1, non-O139 V. cholerae is reported from Laos. The organisms were unusual in being non-motile. They possessed the Vibrio flagellin flaA gene. Further research to determine the reasons for the non-motility and virulence is required.  相似文献   
17.
Fifteen roe deer were examined at necropsy from Northern Turkey in the period 2006-2010 for the helminth infections. Totally 6470 helminth specimens were collected and identified by morphological criteria. Twenty-five helminth species were identified (1 of the Class Trematoda, 1 of Cestoda and 23 of Nematoda). Dicrocoelium dendriticum (Prevalence 20%) was found in liver. Cysticercus tenuicollis (6.6%) was found in mesentery. Haemonchus contortus (53.3%), Ostertagia leptospicularis (73.3%), O. leptospicularis (minor morph: kolchida) (53.3%), Ostertagia ostertagi (26.6%), Spiculopteragia spiculoptera (66.6%), S. spiculoptera (minor morph: mathevossiani) (6.6%), Teladorsagia circumcincta (40.0%), T. circumcincta (minor morph: davtiani) (6.6%), T. circumcincta (minor morph: trifurcata) (6.6%), Trichostrongylus axei (66.6%) were found in abomasum. Trichostrongylus andreevi (6.6%), T. colubriformis (6.6%), T. longispicularis (26.6%), T. vitrinus (40.0%), T. capricola (6.6%), Cooperia oncophora (26.6%), C. punctata (6.6%), Nematodirus filicollis (66.6%), and Capillaria bovis (26.6%) were found in small intestine. Oesophagostomum venulosum (46.6%), Chabertia ovina (26.6%), and Trichuris ovis (13.3%) were found in large intestine. Dictyocaulus capreolus (6.6%) was found in lungs.  相似文献   
18.
Leptospirosis is a worldwide zoonosis. The importance of urban leptospirosis is recognized in Japan: urban rats carry pathogenic leptospires and people acquire these pathogens through contact with surface water or soil contaminated by the urine of the infected animals. To determine the current Leptospira carriage rate in urban rats, 29 wild rats were trapped in the central area of Fukuoka and strains isolated from their kidneys and urine analyzed. When semi‐solid Korthof's medium containing 0.1% agar was used for isolation, 72.2% and 30.8% of the kidney and urine cultures, respectively, were found to be Leptospira‐positive. The isolates belonged to Leptospira interrogans, and were classified into two groups (serogroups Pomona and Icterohaemorrhagiae) based on the results of gyrB sequence analysis and microscopic agglutination testing (MAT). Strains belonging to serogroup Icterohemorrhagiae grew well in liquid medium. On the other hand, serogroup Pomona isolates multiplied very little in liquid medium, but did grow in a semi‐solid medium. Although strains belonging to serogroup Pomona have not been recognized as native to Japan, this strain may be widely distributed in urban rats. Representative strains from each group were found to be highly pathogenic to hamsters. Our findings should serve as a warning that it is still possible to become infected with leptospires from wild rats living in inner cities of Japan. Furthermore, the use of semi‐solid medium for culture will improve the isolation rate of leptospires from the kidneys of wild rats.  相似文献   
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20.
New binary copper(II) complexes [Cu(4-mphen)2(NO3)]NO3·H2O (1), [Cu(5-mphen)2 (NO3)]NO3·H2O (2), the known complex [Cu(dmphen)2(NO3)]NO3 (3) and [Cu(tmphen)2 (NO3)]NO3·H2O (4) - (4-mphen: 4-methyl-1,10-phenanthroline, 5-mphen: 5-methyl-1,10-phenanthroline, dmphen: 4,7-dimethyl-1,10-phenanthroline, tmphen: 3,4,7,8-tetramethyl-1,10-phenanthroline), have been synthesized and characterized by CHN analysis, ESI-MS, FTIR and single-crystal X-ray diffraction techniques. Interaction of these complexes with calf thymus DNA (CT-DNA) has been investigated by absorption spectral titration, ethidium bromide (EB) and Hoechst 33,258 displacement assay and thermal denaturation measurement. These complexes cleaved pUC19 plasmid DNA in the absence and presence of an external agent. Notably, in the presence of H2O2 as an activator, the cleavage abilities of these complexes are obviously enhanced at low concentration. Addition of hydroxyl radical scavengers like DMSO shows significant inhibition of the DNA cleavage activity of these complexes. BSA quenching mechanism was investigated with regard to the type of quenching, binding constant, number of binding locations and the thermodynamic parameters. The experimental results suggested that the probable quenching mechanism was an unusual static process and hydrophobic forces play a dominant role. The CT-DNA and BSA binding efficiencies of these complexes follow the order: 4 > 3 > 1 > 2. Furthermore, in vitro cytotoxicities of these complexes on tumor cells lines (Caco-2, MCF-7 and A549) and healthy cell line (BEAS-2B) showed that these complexes exhibited anticancer activity with low IC50 values. The effect of hydrophobicity of the methyl-substituted phenanthrolines on DNA and protein binding activities of these complexes is discussed.  相似文献   
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