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31.
Under specific culture conditions, umbilical cord blood derived mesenchymal stem cells (MSCs) can differentiate into osteogenic, adipogenic, and chondrogenic lineages. The purpose of the current study was to assess the differentiation potential of osteogenic umbilical cord blood derived hematopoietic stem cells (HSCs) and to develop an appropriate osteogenic differentiation medium for in vitro differentiation of umbilical cord blood derived HSCs. The study was conducted on 20 cord blood samples. The cells were cultured in osteogenic differentiating medium for 3?weeks. The HSCs differentiated into osteoblasts, which expressed osteoblast-associated genes (osteocalcin and bone sialoprotein), which were detected by RT-PCR. They showed alkaline phosphatase activity and a positive Alizarin red-S (AR-S) stain (calcium phosphate deposition). Umbilical cord blood is a rich source of hematopoietic stem cells that can be differentiated into osteoblasts; thus, it can be used for therapeutic strategies in the context of regenerative therapy.  相似文献   
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Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Genetic polymorphisms in the folate metabolic pathway may contribute to the susceptibility to childhood ALL because they affect the DNA synthesis, methylation, and repair. The most common polymorphisms are methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C. The current study aimed at detecting the frequency of these two genetic polymorphisms in de novo ALL patients, and to clarify their impact on the response to induction chemotherapy, as well as treatment toxicity. MTHFR C677T and A1298C polymorphisms were tested in 30 de novo ALL patients by restriction fragment length polymerase chain reaction technique. Thirty normal age- and sex-matched subjects were subjected to the same analysis as a control group. The frequency of MTHFR A1298C gene polymorphism was significantly lower in ALL patients than the controls thus showing a protective effect. The two polymorphisms had no effect on the response to induction chemotherapy. As regards the treatment toxicity, MTHFR C677T polymorphism was associated with marked thrombocytopenia, while A1298C polymorphism was associated with hepatic toxicity. Identifying predictors of methotrexate sensitivity may lead to the development of individualized treatment strategies with improved efficacy and reduced toxicity as well as adjusting the initial methotrexate dose.  相似文献   
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This study aimed at evaluating the reactivity of L ‐Tryptophan (TRP) 1 towards various chemical reagents to produce new bi‐ and tri‐heterocyclic systems providing basic pharmacological activities. Indol‐3‐yl hydroxyoxazol‐2‐yl acetonitrile derivatives 5 and 6 , indol‐3‐yl‐hydroxyoxazol‐2‐yl‐1,2,4‐triazine derivatives 8 and 9, indol‐3‐yl‐hydroxyoxazol‐2‐yl‐aminopyrazole derivatives 11a, b, and indol‐3‐yl‐hydroxyoxazol‐2‐yl‐aminoisoxazole derivative 12 were synthesized via straightforward and efficient methods. The structures were characterized by spectral data (IR, 1H‐NMR, 13C‐NMR, and MS) and the purity was ascertained by microanalysis. Also, this work was extended to study the potential role of the novel synthesized TRP derivatives 5 , 6 , 9 , 11a , and 12 as antidepressant and sedative agents in comparison with TRP. All compounds showed significant antidepressant activity in the forced‐swimming test at two doses (50 or 100 mg/kg). Also, all tested compounds (at 50 or 100 mg/kg) produced a significant decrease in locomotor activity of mice during a 30 min observation period. The most potent antidepressant and sedative effect was produced by the tri‐heterocyclic compounds 9 and 12 , followed by 11a and TRP.  相似文献   
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The essential oil from aerial parts of Psoralea pubescence (Miq.) Standl (Leguminoseae) was analyzed by gas chromatography (GC) and GC/mass spectroscopy systems. The major components identified were psoralen (24.8%), bakuchiol (21.3%), β-caryophyllene (8.5%), germacrene D (6.8%), and α-humulene (4.6%). The major volatiles released by β-glucosidase treatment of the aqueous plant residue were δ-pinene (28.3%), germacrene D (13.6%), and tricyclene (10.2%). The oil showed significant antibacterial activity against Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, and Pseudomonas aeruginosa, while the β-glucosidase-liberated fraction was inactive.  相似文献   
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AIM: To investigate the hematological parameters, biochemical and electrophysiological role of acrylamide (ACR) in the retina and to assess whether selenium (Se) has protective potential in experimental oral intoxication with ACR.METHODS: Sixty Wistar age matched-albino rats (3mo) weighing 195-230 g comprised of both sex were divided into 4 groups. Group I served as the control one in which animals take saline; group II was animals administrated ACR in dose of 15 mg/kg body weight per day for 28d; group III was animals received ACR then additionally Se (0.1 mg/kg body weight) for 28d; and group IV was animals received Se only (0.1 mg/kg body weight) for 28d. Blood analysis and serum trace element levels (Fe, Cu, and Zn) were measured. The electroretinogram (ERG) was recorded, the levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) in the retinal tissues were determined. Moreover the regulation of ion channels such as calcium, sodium and potassium were studied. All measurements were done for all groups after 28d.RESULTS:Administration of ACR in group II caused a significant decrease (P<0.05) in hemoglobin (Hb), red blood cells (RBCs), hematocrit (HCT), white blood cells (WBCs) and lymphocyte of rats. A significant decrease (P<0.05) in Zn level, and alkaline phosphatase enzyme was observed compared to control. ERG which is a reflection of the electric activity in the retina; a- and-b wave amplitudes in ACR group had a reduction of 40% and 20% respectively. These changes accompanied by significant increases (P<0.05) in MDA level in the ACR group, in contrast with GSH-Px which is significant decreased (P<0.05). Moreover sodium and calcium were significant increased but potassium was significant decreased (P<0.05) compared to control group. There were no significant differences between group III (treated with Se) and control in all hematological parameter. Also serum trace elements levels (Cu, Fe and Zn), alkaline phosphatase enzyme and electric activity of the retina didn’t change compared to control due to Se treatment.CONCLUSION: This study provides evidence for the protective effect of Se on acrylamide induced toxicity by reducing oxidative stress.  相似文献   
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