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941.
942.
Fuying?Ma Zheng?Xiong Yubin?Zheng Xiaochen?Yu Xiaoyu?ZhangEmail author 《World journal of microbiology & biotechnology》2008,24(11):2627-2632
A repeated batch operation is developed for the treatment of alkaline pulp black liquor, through a process of biological acidification
precipitation of lignin using brown rot fungus Fomitopsis sp. IMER2. The results showed that COD and color removal of black liquor was dependent on the biomass concentration, pH decrease
and initial COD. Based on these results, the repeated batch process was successfully carried out 12 times over 36 days in
an air bubble column bioreactor. The average reduction of COD and color was approximately 40% and 70%, respectively. 相似文献
943.
Xiaofeng Wang Martin Brandsma Reynald Tremblay Denis Maxwell Anthony M Jevnikar Norm Huner Shengwu Ma 《BMC biotechnology》2008,8(1):87
Background
Human glutamic acid decarboxylase 65 (hGAD65) is a key autoantigen in type 1 diabetes, having much potential as an important marker for the prediction and diagnosis of type 1 diabetes, and for the development of novel antigen-specific therapies for the treatment of type 1 diabetes. However, recombinant production of hGAD65 using conventional bacterial or mammalian cell culture-based expression systems or nuclear transformed plants is limited by low yield and low efficiency. Chloroplast transformation of the unicellular eukaryotic alga Chlamydomonas reinhardtii may offer a potential solution. 相似文献944.
Liu Y Wang Y Jiang Y Zhu N Liang H Xu L Feng X Yang H Ma T 《Biochemical and biophysical research communications》2008,373(1):113-118
Recent efforts have made significant progress in generating transgenic pigs with the ΔF508-CFTR mutation to model the lung and pancreatic disease of human cystic fibrosis. However, species differences in the processing and function of human, pig and mouse ΔF508-CFTR reported recently raise concerns about the phenotypic consequence of the gene-targeted pig model. The purpose of the present study was to characterize the ΔF508 mutant of porcine CFTR to evaluate the severity of its processing defect. Biochemical and immunofluorescence analysis in transfected COS7 and FRT cells indicated that pig ΔF508-CFTR efficiently targets to the plasma membrane and is present mainly as the mature glycosylated protein. Functional characterization in stably transfected FRT cells by fluorometric and electrophysiological assays supported efficient plasma membrane targeting of pig ΔF508-CFTR. The mild cellular processing defect of pig ΔF508-CFTR suggests that its gene-targeted pig model may not develop the lung and pancreatic phenotypes seen in CF patients. 相似文献
945.
Ping He Yue Ma Hongyan Dai Linguang Li Yuexue Liu He Li Guiling Zhao Zhihong Zhang 《Journal of Plant Biology》2012,55(1):1-7
Retrotransposons are the most abundant mobile elements in the plant genome and seem to play an important role in genome reorganization
induced by environmental challenges. Their success in this function depends on the ability of their promoters to regulate
plant adaptation to biotic and abiotic stresses. In this study, the promoter region of FaRE1 was amplified in the strawberry genome, and promoter::GUS fusion was constructed. We produced transgenic strawberry plants
carrying FaRE1 promoter::GUS-fusion genes, and monitored GUS reporter activity. Histochemical and fluorimetric GUS analysis these plants
showed the characteristics of the FaRE1 promoter were activated by either hormones treatments with ABA, NAA, and 2,4-D or cold stress. In addition, we found the
GUS reporter was activated in the leaves of transgenic strawberry plants using 5-azaC. These results suggest that the promoter
of FaRE1 may act as different signal transduction pathways, allowing FaRE1 retrotransposon to be activated in response to multiples challenges. 相似文献
946.
Gochuico BR Zhang J Ma BY Marshak-Rothstein A Fine A 《American journal of physiology. Lung cellular and molecular physiology》2000,278(5):L1045-L1050
TRAIL is a cell-associated tumor necrosis factor-related apoptosis-inducing ligand originally identified in immune cells. The ligand has the capacity to induce apoptosis after binding to cell surface receptors. To examine TRAIL expression in murine vascular tissue, we employed in situ hybridization and immunohistochemistry. In these studies, we found that TRAIL mRNA and protein were specifically localized throughout the medial smooth muscle cell layer of the pulmonary artery. Notably, a similar pattern of expression was observed in the mouse aorta. Consistent with these findings, we found that cultures of primary human aorta and pulmonary artery smooth muscle cells express abundant TRAIL mRNA and protein. We also found that these cells and endothelial cells undergo cell lysis in response to exogenous addition of TRAIL. Last, we confirmed that TRAIL specifically activated a death program by confirming poly(ADP ribose) polymerase cleavage. Overall, we believe that these findings are relevant to understanding the factors that regulate cell turnover in the vessel wall. 相似文献
947.
Lee KY Jeong JW Wang J Ma L Martin JF Tsai SY Lydon JP DeMayo FJ 《Molecular and cellular biology》2007,27(15):5468-5478
The process of implantation, necessary for all viviparous birth, consists of tightly regulated events, including apposition of the blastocyst, attachment to the uterine lumen, and differentiation of the uterine stroma. In rodents and primates the uterine stroma undergoes a process called decidualization. Decidualization, the process by which the uterine endometrial stroma proliferates and differentiates into large epithelioid decidual cells, is critical to the establishment of fetal-maternal communication and the progression of implantation. The role of bone morphogenetic protein 2 (Bmp2) in regulating the transformation of the uterine stroma during embryo implantation in the mouse was investigated by the conditional ablation of Bmp2 in the uterus using the (PR-cre) mouse. Bmp2 gene ablation was confirmed by real-time PCR analysis in the PR-cre; Bmp2fl/fl (termed Bmp2d/d) uterus. While littermate controls average 0.9 litter of 6.2+/-0.7 pups per month, Bmp2d/d females are completely infertile. Analysis of the infertility indicates that whereas embryo attachment is normal in the Bmp2d/d as in control mice, the uterine stroma is incapable of undergoing the decidual reaction to support further embryonic development. Recombinant human BMP2 can partially rescue the decidual response, suggesting that the observed phenotypes are not due to a developmental consequence of Bmp2 ablation. Microarray analysis demonstrates that ablation of Bmp2 leads to specific gene changes, including disruption of the Wnt signaling pathway, Progesterone receptor (PR) signaling, and the induction of prostaglandin synthase 2 (Ptgs2). Taken together, these data demonstrate that Bmp2 is a critical regulator of gene expression and function in the murine uterus. 相似文献
948.
Visfatin levels do not change after the oral glucose tolerance test and after a dexamethasone-induced increase in insulin resistance in humans 总被引:1,自引:0,他引:1
Marcinkowska M Lewandowski KC Lewiński A Bieńkiewicz M Basińska-Lewandowska M Salata I Randeva HS 《Endokrynologia Polska》2007,58(3):188-194
INTRODUCTION, MATERIAL AND METHODS: Visfatin is a cytokine, mainly expressed in visceral fat, that exerts insulin-mimicking effects in rodents through activation of an insulin receptor, although the binding-site is distinct from that of insulin. However, the mechanisms that regulate visfatin synthesis are still not fully understood. In particular, it is not clear whether short-term glucose-induced hyperglycaemia and hyperinsulinaemia as well as a glucocorticoid-induced increase in insulin resistance are reflected in appreciable alterations in serum visfatin levels in humans. In order to investigate this we measured serum visfatin, glucose and insulin concentrations during a 75.0 gram oral glucose tolerance test (OGTT) [Study 1], as well as before and after oral administration of dexamethasone [Study 2]. Study 1 included 17 subjects (2 males), aged 35.7 +/- 15.6 (mean +/- SD) years of BMI 35.2 +/- 9.3 kg/m(2). Blood samples were taken before (0 minutes) and at 60 and 120 minutes after glucose administration. Study 2 included 20 subjects (4 males, 5 subjects with type 2 diabetes), aged 42.1 +/- 17.2 years of BMI 36.7 +/- 8.38 kg/m(2) who underwent screening for Cushing's disease/syndrome. Dexamethasone was administered at a dose of 0.5 mg every 6 hours for 48 hours. Fasting serum concentrations of visfatin, glucose and insulin were assessed before (D0) and after 48 hours of dexamethasone administration (D2). Insulin resistance was assessed according to the HOMA method in non-diabetic individuals (n = 15). RESULTS: In Study 1 two subjects were found to have impaired glucose tolerance and one subject was found to have diabetes mellitus. Glucose administration resulted in a highly significant increase in insulin (from 11.4 +/- 7.2 microU/mL at 0 min to 98.9 +/- 68.6 microU/mL at 60 min and 72.6 +/- 45.1 microU/mL at 120 minute of OGTT, p < 0.001 for 60 and 120 minutes in comparison to baseline). However, there was no change in serum visfatin concentrations (84.6 +/- 11.6 ng/mL at 0 minutes, 82.6 +/- 12.7 ng/mL at 60 minutes and 81.1 +/- 14.5 ng/mL at 120 minutes of OGTT, p = ns). All subjects in Study 2 achieved suppression of cortisol concentrations below 50 nmo/l. Dexamethasone administration resulted in an increase in fasting insulin (from 11.5 +/- 6.9 to 16.9 +/- 7.6 microU/mL; p = 0.011) and an increase in HOMA (from 2.73 +/- 1.74 to 4.02 +/- 2.27; p = 0.015), albeit without a significant change in serum visfatin concentrations (61.1 +/- 19.8 vs. 68.3 +/- 19.4 ng/mL, p = ns). In neither Study 1 nor Study 2 was there any significant correlation between serum visfatin and age, BMI or HOMA. CONCLUSIONS: There is a striking difference between the marked rise in insulin concentrations and the lack of change in visfatin concentrations during the oral glucose tolerance test. This implies that it is highly unlikely that visfatin is involved in the short-term regulation of glucose homeostasis in human subjects. Dexamethasone administration (4 mg/48 hours) induces an increase in insulin resistance, although without significant change in serum visfatin concentrations. Therefore in contrast to the in vitro data, short term glucocorticoid administration does not result in appreciable changes in serum levels of this adipocytokine. Furthermore, the results of our study do not support the notion that glucocorticoid-induced insulin resistance is likely to be related to changes in serum concentrations of visfatin. 相似文献
949.
950.