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101.
BACKGROUND: Osmotic nephrosis is a form of renal tubular injury that has been found in patients treated with intravenous immunoglobulin (IVIG). CASE: A 46-year-old male who had two courses of chemotherapy for acute myelogenous leukemia was found to have refractory thrombocytopenia. After IVIG (Sandoglobulin 12%, Novartis) administration (1 g/kg) for five consecutive days, the patient became oliguric and eventually anuric on the fifth dose. Hemodialysis was initiated, and urine production was noted on day 2 of hospitalization. Routine cytologic examination of fresh, voided urine showed numerous macrophagelike, bland epithelial cells with abundant, multivacuolated cytoplasm. Cytokeratin immunostain revealed positivity, thus confirming the epithelial origin of these cells. CONCLUSION: To our knowledge, this is the first such case reported in the English-language cytology literature. Awareness of a patient's clinical history may be helpful in avoiding an incorrect diagnosis. Urine cytology may be useful in obtaining an early diagnosis of osmotic nephrosis in patients receiving high-dose IVIG therapy that may eliminate the need for a renal biopsy. 相似文献
102.
Sachetelli S Khalil H Chen T Beaulac C Sénéchal S Lagacé J 《Biochimica et biophysica acta》2000,1463(2):254-266
It was previously demonstrated that fluid liposomal-encapsulated tobramycin, named Fluidosomes, was successful in eradicating mucoid Pseudomonas aeruginosa in an animal model of chronic pulmonary infection, whereas free antibiotic did not reduce colony-forming unit (CFU) counts (C. Beaulac et al., Antimicrob. Agents Chemother. 40 (1996) 665-669; C. Beaulac et al., J. Antimicrob. Chemother. 41 (1998) 35-41). These liposomes were also shown to be bactericidal in in vitro tests against strong resistant P. aeruginosa 64 microg/ml). The time needed to reach the maximal fusion rate was about 5 h for the resistant strain comparatively to much shorter time for the sensitive strain. The specific characteristics of Fluidosomes could help overcome bacterial resistance related to permeability barrier and even enzymatic hydrolysis considering the importance of synergy in the whole process of antibiotic resistance. 相似文献
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104.
The micronization of ampicillin via supercritical gas antisolvent (GAS) process was studied. The particle size distribution was significantly controlled with effective GAS variables such as initial solute concentration, temperature, pressure, and antisolvent addition rate. The effect of each variable in three levels was investigated. The precipitated particles were analyzed with scanning electron microscopy (SEM) and Zetasizer Nano ZS. The results indicated that decreasing the temperature and initial solute concentration while increasing the antisolvent rate and pressure led to a decrease in ampicillin particle size. The mean particle size of ampicillin was obtained in the range of 220–430 nm by varying the GAS effective variables. The purity of GAS-synthesized ampicillin nanoparticles was analyzed in contrast to unprocessed ampicillin by FTIR and HPLC. The results indicated that the structure of the ampicillin nanoparticles remained unchanged during the GAS process.KEY WORDS: ampicillin, nanoparticles, precipitation, supercritical gas antisolvent 相似文献
105.
106.
Ranad Shaheen Hanan E. Shamseldin Catrina M. Loucks Mohammed Zain Seidahmed Shinu Ansari Mohamed Ibrahim Khalil Nadya Al-Yacoub Erica E. Davis Natalie A. Mola Katarzyna Szymanska Warren Herridge Albert E. Chudley Bernard N. Chodirker Jeremy Schwartzentruber Jacek Majewski Nicholas Katsanis Coralie Poizat Colin A. Johnson Jillian Parboosingh Kym M. Boycott A. Micheil Innes Fowzan S. Alkuraya 《American journal of human genetics》2014
107.
108.
Zeinab I. Khalil Mohsen M. S. Asker Salwa El-Sayed Imam A. Kobbia 《World journal of microbiology & biotechnology》2010,26(7):1225-1231
The goal of the present investigation was to study the effect of pH on growth and biochemical responses of Dunaliella bardawil and Chlorella ellipsoidea when exposed to different pH values. The two tested microalgae could grow in a wide range of pH (4–9 for D. bardawil and 4–10 for C. ellipsoidea). The dry weight gain and the biochemical components of D. bardawil were greatly enhanced at pH 7.5. In contrast, dry weight and carbohydrate content of C. ellipsoidea attained their maximum values at the alkaline pH. On the other hand, the protein content of C. ellipsoidea recorded its highest value at pH 4, while the pigment content of the same alga was highest at pH 4, 6, and 7.5 and decreased
at alkaline pH. Both pH 6 and pH 9 stimulated the accumulation of β-carotene, vitamin E and vitamin C in D. bardawil, with the highest values of the three compounds recorded at pH 9. In the case of C. ellipsoidea, β-carotene content increased at pH 6 and pH 10 as compared with the control, but the amount of β-carotene was much higher
at pH 6 than at pH 10. Vitamin E content was higher in C. ellipsoidea cells at pH 10 than at pH 6. Both pH 6 and pH 10 caused a significant decline in vitamin C content of C. ellipsoidea. 相似文献
109.
Our aim in this study was to investigate the effect of aging on the capacity of HDLs to promote reverse cholesterol transport. HDLs were isolated from plasma of young (Y-HDL) and elderly (E-HDL) subjects. HDL-mediated cholesterol efflux was studied using THP-1 and J774 macrophages. Our results show that E-HDLs present a lower capacity to promote cholesterol efflux than Y-HDLs (41.7 +/- 1.4% vs. 49.0 +/- 2.2%, respectively; P = 0.013). Reduction in the HDL-mediated cholesterol efflux capacity with aging was more significant with HDL(3) than HDL(2) (Y-HDL(3), 57.3 +/- 1% vs. E-HDL(3), 50.9 +/- 2%; P = 0.012). Moreover, our results show that ABCA1-mediated cholesterol efflux is the more affected pathway in terms of cholesterol-removing capacity. Interestingly, the composition and structure of HDL revealed a reduction in the phosphatidylcholine-sphingomyelin ratio (E-HDL, 32.7 +/- 2.7 vs. Y-HDL, 40.0 +/- 1.9; P = 0.029) and in the phospholipidic layer membrane fluidity in E-HDL compared with Y-HDL as well as an alteration in the apolipoprotein A-I structure and charge. In conclusion, our results shown that E-HDLs present a reduced capacity to promote cholesterol efflux, principally through the ABCA1 pathway, and this may explain the increase of the incidence of cardiovascular diseases observed during aging. 相似文献
110.
Sahar F. Deraz Martin Hedström Eva Nordberg Karlsson Sara Linse Ashraf A. Khalil Bo Mattiasson 《World journal of microbiology & biotechnology》2007,23(7):911-921
Lactobacillus acidophilus DSM 20079 is the producer of a novel bacteriocin termed acidocin D20079. In this paper, a partial sequence of this peptide
is determined, together with data on its secondary structure. A modification of the MRS-growth medium (replacing the detergent
Tween 80 with oleic acid), was shown to improve the production level of the peptide by one order of magnitude, as well as
to stabilize the activity level. Addition of a detergent (Tween 20, less interfering in mass spectrometric analysis), was
however necessary for solubilization of the purified acidocin D20079. Digestion of the peptide followed by de-novo sequencing
of generated fragments, allowed determination of a partial sequence consisting of 39 of the totally estimated 65 residues.
Acidocin D20079 has a high content of glycine residues, hydrophobic residues, and acidic residues. No modified amino acids
were found. Edman degradation, and C-terminal sequencing failed, suggesting that the peptide may be cyclic, and a novel member
of class IIc bacteriocins. Circular dichroism spectroscopy and secondary structure prediction showed random coil conformation
in aqueous solution, but secondary structure was induced in the presence of sodium-dodecyl sulfate. The data could be fitted
assuming 2–13% of the residues to be in α-helix and 23–27% of the residues to be in β-strand conformation. This indicates
that a membrane/membrane-mimicking hydrocarbon–water interface induces an active conformation. 相似文献