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81.
De novo reference intervals (RIs) for a total of thirty two hematological and serum biochemical attributes were established for rainbow trout (Oncorhynchus mykiss) cultured in Himalayan aquaculture system. For this purpose, long term assessment of hemato-biochemical parameters was carried over a period of one year from March 2019 to February 2020 and a total of 444 blood samples were analysed. Blood examination results were recorded systematically and reference intervals were established, notably for erythrocyte parameters: hematocrit (Hct) 29–40%, hemoglobin 8.32–12.28 g/dL, red blood cell (RBC) count 1.01–2.04 (×106/mm3); leukocyte parameters (x 103/mm3): total leukocytes 31.32–90.60, neutrophils 4.21–18.85, total lymphocytes 20.55–63.63, small lymphocytes 14.86–46.50, large lymphocytes 6.35–22.34 and monocytes 1.22–7.56; thrombocyte count 23.00–68.00 (×106/mm3). RIs were also established for red blood cell indices, vital serum constituents involved in carbohydrate, protein, lipid and nitrogen metabolism including the less known, diagnostically important, serum enzymes and electrolyte concentrations. Principal component analysis revealed that certain serum components were more efficient at distinguishing between the life stages (juvenile, adult) of fish by explaining about 92.7% of variation in the whole dataset compared to the principal hematological components which explained only about 80% of the variation. Significant (P < 0.05) differences were noted for RBC count, total leukocyte count (TLC), total protein, total cholesterol and uric acid with respect to the sex of fish. Moreover, clearly differentiable morphometric and morphological attributes were also noticed among erythrocytes, leukocytes (lymphocytes, neutrophils and monocytes) and thrombocytes. To our knowledge, the present study is the first of its kind that elucidates blood chemistry of cultured rainbow trout, O. mykiss in accordance to the guidelines framed by the American society of veterinary clinical pathologists (ASVCP). RIs reported here can help monitor the fish health status by improving the use of non-lethal diagnostics in piscine medicine. 相似文献
82.
Mikheikin A. L. Chudinov A. V. Yaroshchuk A. I. Rubina A. Yu. Pan'kov S. V. Krylov A. S. Zasedatelev A. S. Mirzabekov A. D. 《Molecular Biology》2003,37(6):902-911
To assess the DNA amount in samples (e.g., in biological microchip gel pads) by means of fluorescent dyes, one should use the dyes whose fluorescence weakly depends on DNA composition and structure. With the ImD-310 dye created for this purpose, we have analyzed the staining of single- and double-stranded oligo- and polynucleotides of different nucleotide composition, length, and concentration both in solution and being immobilized in biological microchip gel pads. It turned out that ImD-310 has no pronounced specificity to the single- and double-stranded nucleotide sequences, while the intensity of fluorescence for the dye complexes with d(A)8, d(T)8, d(C)8, and d(G)8 at high temperatures (50°C) differs by less than 25%. A linear correlation has been established between the intensity of fluorescence and the amount of oligonucleotides immobilized on a biological microchip. The plots of the intensity of fluorescence against the concentration of NaCl and the temperature were obtained. By using a generic microchip containing all 4096 hexamer oligonucleotides, it has been determined that the dye has no distinct specificity to any certain motifs of the nucleotide sequence. Thus, ImD-310 may serve as an efficient fluorescent probe to quickly estimate the amount of oligonucleotides immobilized in a microchip, in an electrophoretic gel, etc. 相似文献
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85.
Dodge ME Moon J Tuladhar R Lu J Jacob LS Zhang LS Shi H Wang X Moro E Mongera A Argenton F Karner CM Carroll TJ Chen C Amatruda JF Lum L 《The Journal of biological chemistry》2012,287(27):23246-23254
86.
Zubtsov DA Ivanov SM Rubina AY Dementieva EI Chechetkin VR Zasedatelev AS 《Journal of biotechnology》2006,122(1):16-27
Protein hydrogel-based microchips are being developed for high-throughput evaluation of the concentrations and activities of various proteins. To shorten the time of analysis, the reaction-diffusion kinetics on gel microchips should be accelerated. Here we present the results of the experimental and theoretical analysis of the reaction-diffusion kinetics enforced by mixing with peristaltic pump. The experiments were carried out on gel-based protein microchips with immobilized antibodies under the conditions utilized for on-chip immunoassay. The dependence of fluorescence signals at saturation and corresponding saturation times on the concentrations of immobilized antibodies and antigen in solution proved to be in good agreement with theoretical predictions. It is shown that the enhancement of transport with peristaltic pump results in more than five-fold acceleration of binding kinetics. Our results suggest useful criteria for the optimal conditions for assays on gel microchips to balance high sensitivity and rapid fluorescence saturation kinetics. 相似文献
87.
Endurance training without weight loss lowers systemic, but not muscle, oxidative stress with no effect on inflammation in lean and obese women 总被引:2,自引:1,他引:1
Devries MC Hamadeh MJ Glover AW Raha S Samjoo IA Tarnopolsky MA 《Free radical biology & medicine》2008,45(4):503-511
Obesity is associated with oxidative stress. Endurance training (ET) in healthy individuals increases antioxidant enzyme activity and decreases oxidative stress, whereas its effects on oxidative status in obese humans have yet to be determined. We investigated the effects of obesity and ET on markers of oxidative stress, antioxidant defense, and inflammation. Obese (n=12) and lean (n=12) women underwent 12 weeks of ET with blood, 24-h urine, and muscle biopsies collected prior to and following training for determination of oxidative stress (urinary 8-hydroxy-2-deoxyguanosine and 8-isoprostanes, muscle protein carbonyls, and 4-hydroxynonenal), antioxidant enzyme protein content (muscle CuZnSOD, MnSOD, and catalase), and inflammation (C-reactive protein, leptin, adiponectin, interleukin-6). Obese women had elevated urinary 8-hydroxy-2-deoxyguanosine (P=0.03), muscle protein carbonyls (P=0.03), and 4-hydroxynonenal (P<0.001); serum C-reactive protein (P=0.01); and plasma leptin (P=0.0001) and interleukin-6 (P=0.03). ET decreased urinary 8-hydroxy-2-deoxyguanosine (P=0.006) and 8-isoprostanes (P=0.02) in all subjects and CuZnSOD protein content (P=0.04) in obese women, in the absence of changes in body weight or composition. ET without weight loss decreases systemic oxidative stress, but not markers of inflammation, in obese women. 相似文献
88.
Xu GW Mawji IA Macrae CJ Koch CA Datti A Wrana JL Dennis JW Schimmer AD 《Apoptosis : an international journal on programmed cell death》2008,13(3):413-422
p53 regulates apoptosis and the cell cycle through actions in the nucleus and cytoplasm. Altering the subcellular localization
of p53 can alter its biological function. Therefore, small molecules that change the localization of p53 would be useful chemical
probes to understand the influence of subcellular localization on the function of p53. To identify such molecules, a high-content
screen for compounds that increased the localization of p53 to the nucleus or cytoplasm was developed, automated, and conducted.
With this image-based assay, we identified ellipticine that increased the nuclear localization of GFP-mutant p53 protein but
not GFP alone in Saos-2 osteosarcoma cells. In addition, ellipticine increased the nuclear localization of endogenous p53
in HCT116 colon cancer cells with a resultant increase in the transactivation of the p21 promoter. Increased nuclear p53 after
ellipticine treatment was not associated with an increase in DNA double stranded breaks, indicating that ellipticine shifts
p53 to the nucleus through a mechanism independent of DNA damage. Thus, a chemical biology approach has identified a molecule
that shifts the localization of p53 and enhances its nuclear activity.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
G. Wei Xu and Imtiaz A. Mawji have contributed equally to this work. 相似文献
89.
Impaired endothelial cell proliferation has been proposed to be an early, critical defect contributing to the development of atherosclerosis. Recent studies show that high plasma tumor necrosis factor (TNF)-alpha levels and low serum ascorbic acid (AA) levels correlate with atherosclerosis severity. Additionally, AA has been reported to have potential beneficial effects in preventing atherosclerosis. Based on these studies, we investigated the role of AA (< or =1mM) on TNF-alpha-mediated vascular endothelial cell growth inhibition in vitro. In accordance with previous reports, we found that TNF-alpha alone inhibited endothelial cell proliferation. Further studies revealed that AA alone enhanced endothelial cell proliferation and that AA blocked endothelial cell growth inhibition induced by TNF-alpha. By contrast, we observed no effect of AA on endothelial cell activation or nuclear entry of nuclear factor-kappaB in response to TNF-alpha. The protective effect of AA on endothelial cell proliferation was not simply the result of its antioxidant activity but did correlate with collagen IV expression by endothelial cells. AA pre-treatment of proliferating endothelial cells promoted retinoblastoma protein (Rb) phosphorylation and decreased p53 levels when compared to untreated cells. Furthermore, the addition of AA to TNF-alpha-treated proliferating endothelial cells blocked both the inhibition of retinoblastoma protein phosphorylation and enhanced p53 expression induced by TNF-alpha. Consistent with these results, we found that AA protects endothelial cells against TNF-alpha-induced apoptosis. These studies highlight the potential therapeutic role of AA in promoting endothelial cell proliferation during inflammatory conditions, such as atherosclerosis and cardiovascular disease. 相似文献
90.
Nelofer R Ramanan RN Rahman RN Basri M Ariff AB 《Journal of industrial microbiology & biotechnology》2012,39(2):243-254
Response surface methodology (RSM) and artificial neural network (ANN) were used to optimize the effect of four independent
variables, viz. glucose, sodium chloride (NaCl), temperature and induction time, on lipase production by a recombinant Escherichia coli BL21. The optimization and prediction capabilities of RSM and ANN were then compared. RSM predicted the dependent variable
with a good coefficient of correlation determination (R
2) and adjusted R
2 values for the model. Although the R
2 value showed a good fit, absolute average deviation (AAD) and root mean square error (RMSE) values did not support the accuracy
of the model and this was due to the inferiority in predicting the values towards the edges of the design points. On the other
hand, ANN-predicted values were closer to the observed values with better R
2, adjusted R
2, AAD and RMSE values and this was due to the capability of predicting the values throughout the selected range of the design
points. Similar to RSM, ANN could also be used to rank the effect of variables. However, ANN could not predict the interactive
effect between the variables as performed by RSM. The optimum levels for glucose, NaCl, temperature and induction time predicted
by RSM are 32 g/L, 5 g/L, 32°C and 2.12 h, and those by ANN are 25 g/L, 3 g/L, 30°C and 2 h, respectively. The ANN-predicted
optimal levels gave higher lipase activity (55.8 IU/mL) as compared to RSM-predicted levels (50.2 IU/mL) and the predicted
lipase activity was also closer to the observed data at these levels, suggesting that ANN is a better optimization method
than RSM for lipase production by the recombinant strain. 相似文献