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991.
Synthesis and evaluation of phenoxy acetic acid derivatives as [corrected] anti-mycobacterial agents
Shaharyar M yar MS Siddiqui AA Ali MA 《Bioorganic & medicinal chemistry letters》2006,16(17):4571-4574
In present investigation, 2-(4-formyl-2-methoxyphenoxy) acetic acid on condensation with various ketones in methanolic KOH solution yielded the corresponding chalcones (1-3). These corresponding chalcones were reacted with appropriate acid hydrazide in glacial acetic acid led to the formation of phenoxy acetic acid derivatives. All newly synthesized compounds were evaluated for their anti-mycobacterial activities against Mycobacterium tuberculosis H(37)Rv. 相似文献
992.
Kumar A Pathak SR Ahmad P Ray S Tewari P Srivastava AK 《Bioorganic & medicinal chemistry letters》2006,16(10):2719-2723
A series of aminoalkoxy phenyl-substituted naphthalene-1-yl-methanone was synthesized and tested for its anti-hyperglycemic activity in SLM and STZ-S rat models. Some compounds (3b, 4c and 4h) of the series were showing significant anti-hyperglycemic activity in male Sprague-Dawley rats in sucrose-loaded model (SLM) as well as in streptozotocin-induced model (STZ-S). Active compounds were also evaluated for relative binding affinity against glucagon receptor. 相似文献
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Vascular endothelial growth factor-D activates VEGFR-3 expressed in osteoblasts inducing their differentiation 总被引:6,自引:0,他引:6
Orlandini M Spreafico A Bardelli M Rocchigiani M Salameh A Nucciotti S Capperucci C Frediani B Oliviero S 《The Journal of biological chemistry》2006,281(26):17961-17967
Vascular endothelial growth factor (VEGF)-D is a member of the VEGF family of angiogenic growth factors that recognizes and activates the vascular endothelial growth factor receptor (VEGFR)-2 and VEGFR-3 on blood and/or lymphatic vessels. We show that in the long bones of newborn mice, VEGF-D and VEGFR-3 are expressed in the osteoblasts of the growing plate. The treatment of primary human osteoblasts with recombinant VEGF-D induces the expression of osteocalcin and the formation of mineralized nodules in a dose-dependent manner. A monoclonal neutralizing antibody, anti-VEGF-D, or silencing of VEGFR-3 by lentiviral-mediated expression of VEGFR-3 small hairpin RNA affects VEGF-D-dependent osteocalcin expression and nodule formation. Moreover, in primary human osteoblasts, VEGF-D expression is under the control of VEGF, and inhibition of VEGF-D/VEGFR-3 signaling, by monoclonal antibodies or VEGFR-3 silencing, affects VEGF-dependent osteoblast differentiation. These experiments establish that VEGF-D/VEGFR-3 signaling plays a critical role in osteoblast maturation and suggest that VEGF-D is a downstream effector of VEGF in osteogenesis. 相似文献
996.
Payabvash S Beheshtian A Salmasi AH Kiumehr S Ghahremani MH Tavangar SM Sabzevari O Dehpour AR 《Life sciences》2006,79(10):972-980
Recently many researchers have proposed a protective role for morphine against tumor growth and metastasis, especially through induction of apoptosis in tumoral cells. These findings may lead to underestimation of cytotoxic effects of opioid drugs which are usually expected only at high doses. The present study was conducted to clarify whether repeated morphine administration, which is commonly used for relief from chronic pain, would interfere with liver antioxidant defence and hepatocytes vitality. Morphine was injected repeatedly at doses that have been reported to relieve cancer pain and reduce tumor spread in mice (5 and 10 mg/kg/day for nine consecutive days). The changes in hepatic glutathione concentration, its synthesis pathway and enzymatic antioxidant defense revealed the pro-oxidant effects of chronic morphine treatment on the liver. None of these changes were observed in those mice that were co-treated with naltrexone (opioid antagonist) and same doses of morphine. However induction of liver conjugating enzymes following morphine treatment was not receptor mediated. Moreover, chronic morphine treatment induced hepatocytes apoptosis. Interestingly, the apoptotic changes were antagonized by co-administration of either naltrexone or thiol antioxidant. In conclusion, although hepatotoxic effects of morphine at high doses have been reported previously, our findings propose that repeated morphine administration even at lower doses would induce oxidative stress in the liver, which may contribute to induction of apoptosis in hepatocytes. Since many of the observed adverse effects were mediated by opioid receptors, our results suggest that other opioid analgesics should also be used more cautiously. 相似文献
997.
Ahmad S Yousuf S Ishrat T Khan MB Bhatia K Fazli IS Khan JS Ansari NH Islam F 《Life sciences》2006,79(20):1921-1928
Oxidative stress may be regarded as an imbalance between free radical production and opposing antioxidant defenses. Free radical oxidative stress is implicated in rat cerebral ischemia and naturaceutical antioxidants are dietary supplements that have been reported to have neuroprotective activity. Many studies have reported dietary sesame oil (SO) as an effective antioxidant. In the present study the neuroprotective effect of dietary SO was evaluated against middle cerebral artery occlusion (MCAO)-induced cerebral ischemia injury in rats. Rats were fed on diet (20% SO) for 15 days. The middle cerebral artery of adult male Wistar rat was occluded for 2 h and reperfused for 22 h. The antioxidant properties of brain were measured as levels of reduced glutathione (GSH), glutathione-S-transferase (GST), glutathione peroxide (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD) and thiobarbituric acid reactive substance (TBARS). A decrease in the activity of all the enzymatic and non-enzymatic antioxidants was observed along with an increase in lipid peroxidation (LPO) in MCAO group. The neurobehavioral activity of rats was also observed by using videopath analyzer. Dietary SO improved the antioxidant status in MCAO+SO group when compared with MCAO group. The results of neurobehavioral activity also support our biochemical data. The results obtained suggest protective effect of SO against cerebral ischemia in rat brain through their antioxidant properties. 相似文献
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Kerry S. O'Brien Rebecca M. Puhl Janet D. Latner Azeem S. Mir John A. Hunter 《Obesity (Silver Spring, Md.)》2010,18(11):2138-2144
Anti‐fat sentiment is increasing, is prevalent in health professionals, and has health and social consequences. There is no evidence for effective obesity prejudice reduction techniques in health professionals. The present experiment sought to reduce implicit and explicit anti‐fat prejudice in preservice health students. Health promotion/public health bachelor degree program students (n = 159) were randomized to one of three tutorial conditions. One condition presented an obesity curriculum on the controllable reasons for obesity (i.e., diet/exercise). A prejudice reduction condition presented evidence on the uncontrollable reasons for obesity (i.e., genes/environment); whereas a neutral (control) curriculum focused on alcohol use in young people. Measures of implicit and explicit anti‐fat prejudice, beliefs about obese people, and dieting, were taken at baseline and postintervention. Repeated measures analyses showed decreases in two forms of implicit anti‐fat prejudice (decreases of 27 and 12%) in the genes/environment condition relative to other conditions. The diet/exercise condition showed a 27% increase in one measure of implicit anti‐fat prejudice. Reductions in explicit anti‐fat prejudice were also seen in the genes/environment condition (P = 0.006). No significant changes in beliefs about obese people or dieting control beliefs were found across conditions. The present results show that anti‐fat prejudice can be reduced or exacerbated depending on the causal information provided about obesity. The present results have implications for the training of health professionals, especially given their widespread negativity toward overweight and obesity. 相似文献