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981.
Anjali Prabhu Qin Xu Michaele B. Manigrasso Moumita Biswas Elizabeth Flynn Radu Iliescu Edwin D. Lephart Christine Maric 《Steroids》2010,75(11):779-787
Our previous studies have shown that diabetes in the male streptozotocin (STZ)-induced diabetic rat is characterized by a decrease in circulating testosterone and concomitant increase in estradiol levels. Interestingly, this increase in estradiol levels persists even after castration, suggesting extra-testicular origins of estradiol in diabetes. The aim of the present study was to examine whether other target organs of diabetes may be sources of estradiol. The study was performed in male Sprague–Dawley non-diabetic (ND), STZ-induced diabetic (D) and STZ-induced diabetic castrated (Dcas) rats (n = 8–9/group). 14 weeks of diabetes was associated with decreased testicular (ND, 26.3 ± 4.19; D, 18.4 ± 1.54; P < 0.05), but increased renal (ND, 1.83 ± 0.92; D, 7.85 ± 1.38; P < 0.05) and ocular (D, 23.4 ± 3.66; D, 87.1 ± 28.1; P < 0.05) aromatase activity. This increase in renal (Dcas, 6.30 ± 1.25) and ocular (Dcas, 62.7 ± 11.9) aromatase activity persisted after castration. The diabetic kidney also had increased levels of tissue estrogen (ND, 0.31 ± 0.01; D, 0.51 ± 0.11; Dcas, 0.45 ± 0.08) as well as estrogen receptor alpha protein expression (ND, 0.63 ± 0.09; D, 1.62 ± 0.28; Dcas, 1.38 ± 0.20). These data suggest that in male STZ-induced diabetic rats, tissues other than the testis may become sources of estradiol. In particular, the diabetic kidney appears to produce estradiol following castration, a state that is associated with a high degree or renal injury. Overall, our data provides evidence for the extra-testicular source of estradiol that in males, through an intracrine mechanism, may contribute to the development and/or progression of end-organ damage associated with diabetes. 相似文献
982.
Thanemozhi G Natarajan Bhaskar V Kallakury Christine E Sheehan Margaret B Bartlett Natarajan Ganesan Anju Preet Jeffrey S Ross Kevin T FitzGerald 《Cancer cell international》2010,10(1):13
Background
MLL2, an epigenetic regulator in mammalian cells, mediates histone 3 lysine 4 tri-methylation (H3K4me3) through the formation of a multiprotein complex. MLL2 shares a high degree of structural similarity with MLL, which is frequently disrupted in leukemias via chromosomal translocations. However, this structural similarity is not accompanied by functional equivalence. In light of this difference, and previous reports on involvement of epigenetic regulators in malignancies, we investigated MLL2 expression in established cell lines from breast and colon tissues. We then investigated MLL2 in solid tumors of breast and colon by immunohistochemistry, and evaluated potential associations with established clinicopathologic variables. 相似文献983.
April L Ellis Wensheng Pan Guang Yang Kim Jones Christine Chuang John M Whitelock Arthur A DeCarlo 《BMC biotechnology》2010,10(1):66
Background
Heparan sulfate glycosaminoglycans are diverse components of certain proteoglycans and are known to interact with growth factors as a co-receptor necessary to induce signalling and growth factor activity. In this report we characterize heterogeneously glycosylated recombinant human perlecan domain 1 (HSPG2 abbreviated as rhPln.D1) synthesized in either HEK 293 cells or HUVECs by transient gene delivery using either adenoviral or expression plasmid technology. 相似文献984.
Johannes Ott Christine Kurz Kazem Nouri Stefan Wirth Elisabeth Vytiska-Binstorfer Johannes C Huber Klaus Mayerhofer 《Reproductive biology and endocrinology : RB&E》2010,8(1):45
Background
Ovarian stimulation in women with polycystic ovary syndrome (PCOS) increases the risk for perinatal complications. Ovulation induction by laparoscopic ovarian drilling (LOD) might improve the overall pregnancy outcomes. The aim of our study was to assess the adverse events or effects on pregnancy of LOD and clomiphene citrate (CC) stimulation in patients who received metformin. 相似文献985.
Paul D. Cooper Stuart R. Dennis James D. Woodman Ann Cowlings Christine Donnelly 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2010,151(3):298-302
Opioid peptides have been implicated in regulation of feeding in invertebrates. Studies have suggested that receptors for opioids are present in cockroaches and that these receptors play roles in affecting both behaviour and feeding. We examined the effect of µ, δ, and κ opioid receptor agonists and antagonists on feeding, mass changes and activity in the cockroach, Periplaneta americana. The κ antagonist, nor-binaltorphimine, significantly increased food intake, while naltrexone (general antagonist) and naloxonazine (µ antagonist) both reduced feeding. A large mass loss was observed in cockroaches treated with nor-binaltorphimine, despite the increased food intake. Males did not lose as much mass during the 3 h as females, although drug treatment did have some effect on the loss. Time of activity (%) was not influenced by any drug. Water loss experiments suggested that nor-binaltorphimine increased water loss, accounting for the mass loss despite the increased feeding. We suggest that two populations of opioid receptors are present as previously reported, with one affecting feeding and the other involved with evaporative water loss. 相似文献
986.
Unrecognized cardiovascular abnormalities may confound the interpretation of research data collected using rats. However, although SPF rat colonies are screened for microbes and kept under standardized environmental conditions, their cardiovascular status is largely unknown. We recently performed surgery on anesthetized 80-d-old Sprague-Dawley rats and observed a high mortality that could not be attributed to the procedures or preceding treatments. Upon necropsy, cardiomyopathy was readily apparent in a substantial proportion of these rats. To further evaluate the nature of this condition, we evaluated the histology and morphology of hearts from both Sprague-Dawley and Lewis rats. Compared with Lewis rats, Sprague-Dawley rats had greater left ventricular wall thickness and larger cardiomyocyte cell size. Severe left ventricle hypertrophy was present in 38% of young adult Sprague-Dawley rats. These findings may have implications for research models that use Sprague-Dawley rats. 相似文献
987.
988.
Anita B. Hjelmeland Qiulian Wu Sarah Wickman Christine Eyler John Heddleston Qing Shi Justin D. Lathia Jennifer MacSwords Jeongwu Lee Roger E. McLendon Jeremy N. Rich 《PLoS biology》2010,8(2)
Glioblastomas are deadly cancers that display a functional cellular hierarchy maintained by self-renewing glioblastoma stem cells (GSCs). GSCs are regulated by molecular pathways distinct from the bulk tumor that may be useful therapeutic targets. We determined that A20 (TNFAIP3), a regulator of cell survival and the NF-κB pathway, is overexpressed in GSCs relative to non-stem glioblastoma cells at both the mRNA and protein levels. To determine the functional significance of A20 in GSCs, we targeted A20 expression with lentiviral-mediated delivery of short hairpin RNA (shRNA). Inhibiting A20 expression decreased GSC growth and survival through mechanisms associated with decreased cell-cycle progression and decreased phosphorylation of p65/RelA. Elevated levels of A20 in GSCs contributed to apoptotic resistance: GSCs were less susceptible to TNFα-induced cell death than matched non-stem glioma cells, but A20 knockdown sensitized GSCs to TNFα-mediated apoptosis. The decreased survival of GSCs upon A20 knockdown contributed to the reduced ability of these cells to self-renew in primary and secondary neurosphere formation assays. The tumorigenic potential of GSCs was decreased with A20 targeting, resulting in increased survival of mice bearing human glioma xenografts. In silico analysis of a glioma patient genomic database indicates that A20 overexpression and amplification is inversely correlated with survival. Together these data indicate that A20 contributes to glioma maintenance through effects on the glioma stem cell subpopulation. Although inactivating mutations in A20 in lymphoma suggest A20 can act as a tumor suppressor, similar point mutations have not been identified through glioma genomic sequencing: in fact, our data suggest A20 may function as a tumor enhancer in glioma through promotion of GSC survival. A20 anticancer therapies should therefore be viewed with caution as effects will likely differ depending on the tumor type. 相似文献
989.
990.
Raja Brauner Anu Bashamboo Sébastien Rouget Marie Goulet Pascal Philibert Hélène Sarda-Thibault Christine Trivin Micheline Misrahi Charles Sultan Ken McElreavey 《PloS one》2010,5(6)