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1.
Growth characteristics of a thermotolerant methylotrophic Bacillus sp. (NCIB 12522) in batch culture
Nader Al-Awadhi Thomas Egli Geoffrey Hamer 《Applied microbiology and biotechnology》1988,29(5):485-493
Summary This contribution deals with problems associated with the culture of a thermotolerant methylotrophic Bacillus sp. The results reported clearly demonstrate why conventional enrichment/isolation procedures have, in the past, failed to allow such microbes to assert themselves. The catastrophic effect of carbon substrate (methanol) exhaustion on such cultures is clearly evidenced, but the effects of other nutrient exhaustion or limitations are demonstrated to be markedly less stringent. The failure of such cultures to complete the sporulation process when growing on methanol has important consequences with respect to their survival characteristics. 相似文献
2.
Biological Seed Treatment of Corn with Mycopathogenic Fungi 总被引:2,自引:0,他引:2
3.
Rat bone marrow microsomal heme oxygenase activity has been studied and optimal condition for the measurement of this activity are described. The activity of bone marrow heme oxygenase was linear with time and protein concentration as measured under these assay conditions. Bilirubin formation by the heme oxygenase complex system was observed with either a NADPH generating system or with NADH as electron donor. The enzyme activity for heme degradation supported by NADH proceeds at a comparable rate to that observed with NADPH as reducing equivalent. It thus appears that this oxidation reaction must be more complex than simply involving NADPH as the sole election donor as has been previously proposed. 相似文献
4.
Toll-like receptor expression in normal ovary and ovarian tumors 总被引:1,自引:0,他引:1
Mingfu Zhou Molly M. McFarland-Mancini Holly M. Funk Nader Husseinzadeh Taofic Mounajjed Angela F. Drew 《Cancer immunology, immunotherapy : CII》2009,58(9):1375-1385
Recent studies have implicated inflammation in the initiation and progression of ovarian cancer, though the mechanisms underlying
this effect are still not clear. Toll-like receptors (TLRs) allow immune cells to recognize pathogens and to trigger inflammatory
responses. Tumor cell expression of TLRs can promote inflammation and cell survival in the tumor microenvironment. Here we
sought to characterize the expression of TLRs in normal human ovaries, benign and malignant ovarian tumors from patients,
and in established ovarian tumor cell lines. We report that TLR2, TLR3, TLR4, and TLR5 are strongly expressed on the surface
epithelium of normal ovaries. In contrast to previous studies of uterus and endocervix, we found no cyclic variation in TLR
expression occurred in murine ovaries. TLR2, TLR3, TLR4, and TLR5 are expressed in benign conditions, epithelial tumors, and
in ovarian cancer cell lines. Variable expression of TLR6 and TLR8 was seen in benign and malignant epithelium of some patients,
while expression of TLR1, TLR7, and TLR9 was weak. Normal and malignant ovarian stroma were negative for TLR expression. Vascular
endothelial cells, macrophages, and occasional fibroblasts in tumors were positive. Functional activity for TLRs was demonstrated
by stimulation of cell lines with specific ligands and subsequent activation and translocation of NFκB and release of the
proinflammatory cytokines interleukin-6 and CCL-2. These studies demonstrate expression of multiple TLRs in the epithelium
of normal ovaries and in ovarian tumor cells, and may indicate a mechanism by which epithelial tumors manipulate inflammatory
pathways to facilitate tumor progression. 相似文献
5.
Functional organization of adult motor cortex is dependent upon continued protein synthesis 总被引:5,自引:0,他引:5
Kleim JA Bruneau R Calder K Pocock D VandenBerg PM MacDonald E Monfils MH Sutherland RJ Nader K 《Neuron》2003,40(1):167-176
The functional organization of adult cerebral cortex is characterized by the presence of highly ordered sensory and motor maps. Despite their archetypical organization, the maps maintain the capacity to rapidly reorganize, suggesting that the neural circuitry underlying cortical representations is inherently plastic. Here we show that the circuitry supporting motor maps is dependent upon continued protein synthesis. Injections of two different protein synthesis inhibitors into adult rat forelimb motor cortex caused an immediate and enduring loss of movement representations. The disappearance of the motor map was accompanied by a significant reduction in synapse number, synapse size, and cortical field potentials and caused skilled forelimb movement impairments. Further, motor skill training led to a reappearance of movement representations. We propose that the circuitry of adult motor cortex is perpetually labile and requires continued protein synthesis in order to maintain its functional organization. 相似文献
6.
Frits A. Wijburg Bernard Bénichou Daniel G. Bichet Lorne A. Clarke Gabriela Dostalova Alejandro Fainboim Andreas Fellgiebel Cassiano Forcelini Kristina An Haack Robert J. Hopkin Michael Mauer Behzad Najafian C. Ronald Scott Suma P. Shankar Beth L. Thurberg Camilla T?ndel Anna Tylki-Szymańska Uma Ramaswami 《PloS one》2015,10(5)
Trial Design
This analysis characterizes the degree of early organ involvement in a cohort of oligo-symptomatic untreated young patients with Fabry disease enrolled in an ongoing randomized, open-label, parallel-group, phase 3B clinical trial.Methods
Males aged 5–18 years with complete α-galactosidase A deficiency, without symptoms of major organ damage, were enrolled in a phase 3B trial evaluating two doses of agalsidase beta. Baseline disease characteristics of 31 eligible patients (median age 12 years) were studied, including cellular globotriaosylceramide (GL-3) accumulation in skin (n = 31) and kidney biopsy (n = 6; median age 15 years; range 13–17 years), renal function, and glycolipid levels (plasma, urine).Results
Plasma and urinary GL-3 levels were abnormal in 25 of 30 and 31 of 31 patients, respectively. Plasma lyso-GL-3 was elevated in all patients. GL-3 accumulation was documented in superficial skin capillary endothelial cells (23/31 patients) and deep vessel endothelial cells (23/29 patients). The mean glomerular filtration rate (GFR), measured by plasma disappearance of iohexol, was 118.1 mL/min/1.73 m2 (range 90.4–161.0 mL/min/1.73 m2) and the median urinary albumin/creatinine ratio was 10 mg/g (range 4.0–27.0 mg/g). On electron microscopy, renal biopsy revealed GL-3 accumulation in all glomerular cell types (podocytes and parietal, endothelial, and mesangial cells), as well as in peritubular capillary and non-capillary endothelial, interstitial, vascular smooth muscle, and distal tubules/collecting duct cells. Lesions indicative of early Fabry arteriopathy and segmental effacement of podocyte foot processes were found in all 6 patients.Conclusions
These data reveal that in this small cohort of children with Fabry disease, histological evidence of GL-3 accumulation, and cellular and vascular injury are present in renal tissues at very early stages of the disease, and are noted before onset of microalbuminuria and development of clinically significant renal events (e.g. reduced GFR). These data give additional support to the consideration of early initiation of enzyme replacement therapy, potentially improving long-term outcome.Trial Registration
ClinicalTrials.gov NCT00701415 相似文献7.
Sheibani N Scheef EA Dimaio TA Wang Y Kondo S Sorenson CM 《Journal of cellular physiology》2007,210(3):616-625
Bcl-2 is the founding member of a family of proteins that influence apoptosis. During kidney development bcl-2 not only acts as a survival factor, but may also impact cell adhesive mechanisms and by extension branching morphogenesis. The interrelationship between cell adhesion, migration and apoptosis, important during development, is poorly understood. Here we examined the impact lack of bcl-2, an inhibitor of apoptosis, has on ureteric bud (UB) cell adhesion, migration, and branching morphogenesis. Bcl-2 -/- UB cells demonstrated increased cell migration, increased cell invasion and decreased adhesion to vitronectin and fibronectin compared with wild-type cells. Bcl-2 +/+ UB cells readily branched in collagen gel and Matrigel while bcl-2 -/- UB cells did not undergo significant branching in either matrix. Re-expression of bcl-2 in bcl-2 -/- UB cells restored their ability to undergo branching morphogenesis in Matrigel. Consistent with our in vitro data, we show that in the absence of bcl-2, embryonic kidneys undergo decreased UB branching. We observed decreased numbers of UB branch points, UB branch tips and a decreased distance to the first UB branch point in the absence of bcl-2. The alterations in bcl-2 -/- UB cell adhesion and migration was also associated with a significant alteration in expression of a number of extracellular matrix proteins. Bcl-2 -/- UB cells exhibited increased fibronectin expression and decreased thrombospondin-1 and osteopontin expression. Taken together, these data suggest that bcl-2 is required for the proper regulation of cell adhesive and migratory mechanisms, perhaps through modulation of the cellular microenvironment. 相似文献
8.
Soil contamination by organochlorine pesticides or PCBs is almost undocumented for Iran. Here we report a soil survey in Mazandaran and Guilan provinces that hold >30% of the agricultural areas of Iran where pesticide use is widespread. Concentration of DDTs, HCHs, cyclodienes, and PCBs were measured in 45 soil samples from different agricultural land uses and forest land. The average concentrations of ∑DDT (37 μg kg?1) and ∑HCH (21 μg kg?1) in agricultural soils are among the largest ever reported and exceed international soil screening standards. All residues were larger in agricultural than in forest soil. Within agricultural land, ∑DDT were largest for tea gardens, lindane was largest in rice fields, and cyclodiens largest in citrus orchards. The ratio of (DDD + DDE)/DDT is an index of the extent of DDT degradation in soil and was lower in tea gardens than in other soils (0.7 versus 2–5), indicating either ongoing DDT input or lower degradation rate in the tea gardens that are more acid than the other soils (pH 4.5 versus 6.5–7.0). The o,p′–DDT/p,p′–DDT ratio was about 3 in forest soils, suggesting that DDT is derived from dicofol application and not from technical DDT as in agricultural soils. The PCB 28, 180, and 138 showed the highest mean concentration compared with other PCB congeners in all land uses. This survey is the first of this kind for Iran and illustrates that concentrations of organochlorine pesticide in soil are relatively large. 相似文献
9.
10.
Nourizad N Ehn M Gharizadeh B Hober S Nyrén P 《Protein expression and purification》2003,27(2):4600-237
ATP-diphosphohydrolase (apyrase) catalyzes the hydrolysis of phosphoanhydride bonds of nucleoside tri- and di-phosphates in the presence of divalent cations. This enzyme has broad substrate specificity for nucleotides, which makes it an ideal enzyme for different biotechnical applications, such as DNA sequencing and platelet-aggregation inhibition. The only commercially available apyrase is isolated from potato tubers. To avoid batch-to-batch variations in activity and quality, we decided to produce a recombinant enzyme. The methylotrophic yeast Pichia pastoris was chosen as an eukaryotic expression host. The coding sequence of potato apyrase, without the signal peptide, was cloned into the YpDC541 vector to create a fusion with the alpha-mating secretion signal of Saccharomyces cerevisiae. The gene was placed under the control of the methanol-inducible alcohol oxidase promoter. The YpDC541-apyrase construct was integrated into P. pastoris strain SMD1168. Methanol induction resulted in secretion of apyrase to a level of 1mg/L. The biologically active recombinant apyrase was purified by hydrophobic interaction and ion exchange chromatography. According to SDS-PAGE and Western blot analysis, the purified enzyme showed to be hyperglycosylated. By enzymatic removal of N-glycans, a single band corresponding to a molecular mass of 48kDa was detected. The recombinant apyrase was found to function well when it was used in combination with the Pyrosequencing technology. 相似文献