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81.
Mohammadi Salman Shafiee Maryam Faraji Seyed Nooreddin Rezaeian Mohsen Ghaffarian-Bahraman Ali 《Biometals》2022,35(4):711-728
BioMetals - Breast milk is a complete food for the development of the newborn, but it can also be an important route for environmental pollutants transmission to the infants. This study was aimed... 相似文献
82.
83.
Somayeh Sadeghi Negar Seyed Mohammad-Hossein Etemadzadeh Saeid Abediankenari Sima Rafati Tahereh Taheri 《The Korean journal of parasitology》2015,53(4):385-394
Leishmaniasis is a worldwide uncontrolled parasitic disease due to the lack of effective drug and vaccine. To speed up effective drug development, we need powerful methods to rapidly assess drug effectiveness against the intracellular form of Leishmania in high throughput assays. Reporter gene technology has proven to be an excellent tool for drug screening in vitro. The effects of reporter proteins on parasite infectivity should be identified both in vitro and in vivo. In this research, we initially compared the infectivity rate of recombinant Leishmania major expressing stably enhanced green fluorescent protein (EGFP) alone or EGFP-luciferase (EGFP-LUC) with the wild-type strain. Next, we evaluated the sensitivity of these parasites to amphotericin B (AmB) as a standard drug in 2 parasitic phases, promastigote and amastigote. This comparison was made by MTT and nitric oxide (NO) assay and by quantifying the specific signals derived from reporter genes like EGFP intensity and luciferase activity. To study the amastigote form, both B10R and THP-1 macrophage cell lines were infected in the stationary phase and were exposed to AmB at different time points. Our results clearly revealed that the 3 parasite lines had similar in vitro infectivity rates with comparable parasite-induced levels of NO following interferon-γ/lipopolysaccharide induction. Based on our results we proposed the more reporter gene, the faster and more sensitive evaluation of the drug efficiency. 相似文献
84.
The communication or quorum-sensing signal molecules (QSSM) are specialized molecules used by numerous gram-negative bacterial pathogens of animals and plants to regulate or modulate bacterial virulence factor production. In plant-associated bacteria, genes encoding the production of these signal molecules, QSSMs, were discovered to be linked with the phenotype of bacterium, because mutation of these genes typically disrupts some behaviors of bacteria. There are other regulator genes which respond to the presence of signal molecule and regulate the production of signal molecule as well as some virulence factors. The synthesis and regulator genes (collectively called quorum-sensing genes hereafter) are repressed in low bacterial population but induced when bacteria reach to high cell density. Multiple regulatory components have been identified in the bacteria that are under control of quorum sensing. This review describes different communication signal molecules, and the various chemical, physical and genomic factors known to synthesize signals. Likewise, the role of some signal-degrading enzymes or compounds and the interaction of QSSMs with eukaryotic metabolism will be discussed here. 相似文献
85.
86.
The importance of empathetic communication in the context of patient care has been suggested as a crucial element in the delivery of high-quality medical care. Although some countries have measured empathy among medical students, little is known formally about the state of affairs regarding empathy in the UK with regard to gender, medical years and speciality. This paper presents the results from a cross-sectional study that explored the relationship between undergraduate medical students' empathy scores relevant to gender, medical school year and future career ambitions. The Jefferson Scale of Physician Empathy, a self-administered questionnaire, was used for collecting data. It was decided to incorporate the scale into a web application that was only accessible through a confidential hyperlink. A total of 853 (68.2%) medical students completed the survey. Female students (n=470) scored significantly (t((819))=-6.63; 95% CI=-0.30, -0.16) higher than male students (n=351). No significant differences were observed between empathy mean scores and medical school year. Students choosing people-oriented specialities had significantly higher mean scores in comparison to students preferring technology oriented specialities. Three hypotheses were tested in this study. The hypothesis that female students would score higher than male students was supported by the results. The findings did not support the hypothesis that empathy scores decline during the medical school years. Finally, the findings did support the hypothesis that those preferring peopleoriented specialities would score higher on the empathy scale than students choosing technology oriented specialities. Some recommendations are made and the limitations of study are discussed. 相似文献
87.
Mohsen Jalali 《Soil & Sediment Contamination》2011,20(5):493-508
Soil solution chemistry reflects the most dynamic processes occurring in soils and is responsible for their current status. This study was undertaken to determine the soil solution status in 25 mountainous soils. The major cations in the studied soil solutions are in the decreasing order of Ca2+ > Mg2+ > Na+ > K+. The anions are also arranged in decreasing order as HCO? 3 > Cl? > NO? 3 > SO 2? 4 . Concentrations of NO? 3 , P, and K+ in soil solutions were in the range of 12–364 mg l?1, 1.75–34.8 mg l?1, and 0.78– 198 mg l?1, respectively. Results suggest that the concentration of P in the soil solutions could be primarily controlled by of the solubility of octacalcium phosphate and ß-tricalcium phosphate. In general, the greater the dissolved P concentration in the soil solution, the closer the solution was to equilibrium with respect to the more soluble Ca2+ phosphate minerals. Surface soil accumulations of P, NO? 3 , and K+ have occurred in these soils to such an extent that loss of these nutrients in surface runoff and the high risk for nutrient transfer into groundwater in concentrations exceeding the groundwater quality standard has become a priority management concern. 相似文献
88.
Mohsen Akbari Mohammad Hassan Fazaelipoor Ataollah Soltai Goharizi 《Biotechnology and Bioprocess Engineering》2011,16(2):407-412
Water super absorbents are low cross-linked hydrophilic polymers that absorb water in amounts up to several hundred times
their dry weight. In this study, the effect of adding these materials to the bed of a biofilter was investigated. Two equal
size biofilters were used for this purpose. One of the biofilters was packed with a mixture of perlite and a commercial polyacrylamide
based super absorbent (2.3% dry weight), and the other was packed with perlite to perform as a control. The biofilters were
inoculated with a bacterial culture that was able to grow on n-hexane as the sole source of carbon and energy. Both biofilters
removed up to 90% of the entering pollutants when using an inlet n-hexane concentration of 1 g/m3, and an air flow rate of 0.3 L/min (mass loading of 18.34 g/m3/h, and empty bed residence time of 3.27 min). The super absorbent had a positive effect on the performance of the biofilter.
While the difference in the performance of the biofilters was marginal when frequent moistening was applied, the difference
was considerable when moistening was less frequent. 相似文献
89.
Pourghadamyari H Moohebati M Parizadeh SM Falsoleiman H Dehghani M Fazlinezhad A Akhlaghi S Tavallaie S Sahebkar A Paydar R Ghayour-Mobarhan M Ferns GA 《Cell stress & chaperones》2011,16(3):309-316
Antibody titers to several heat shock proteins (anti-Hsps) have been reported to be associated with the severity and progression of cardiovascular disease. However, there are little data regarding anti-Hsp27 titers in patients with coronary artery disease (CAD). A total of 400 patients with suspected CAD were recruited. Based on the results of coronary angiography, these patients were classified into CAD+ (n = 300) and CAD− (n = 100) groups defined as patients with ≥50% and <50% stenosis of any major coronary artery, respectively. Eighty-three healthy subjects were also recruited as the control group. Serum anti-Hsp27 IgG titers were measured using an in-house enzyme-linked immunosorbent assay. CAD+ patients had significantly higher anti-Hsp27 titers compared with both CAD− and control groups. Anti-Hsp27 titers were also higher in the CAD− group compared with the control group. With regard to the number of affected vessels in the CAD+ group, patients with three-vessel disease had higher anti-Hsp27 titers compared with both two-vessel disease (2VD) and one-vessel disease (1VD) subgroups. However, there was no significant difference between 1VD and 2VD subgroups. In multiple linear regression analysis, the number of narrowed vessels and smoking were significant independent determinants of serum anti-Hsp27 titers. The present findings indicate that serum anti-Hsp27 titers may be associated with the presence and severity of coronary artery disease. 相似文献
90.
Molecular characterization of acquired tolerance of tumor cells to picropodophyllin (PPP) 总被引:1,自引:0,他引:1
Hashemi J Worrall C Vasilcanu D Fryknäs M Sulaiman L Karimi M Weng WH Lui WO Rudduck C Axelson M Jernberg-Wiklund H Girnita L Larsson O Larsson C 《PloS one》2011,6(3):e14757